Chemical engineering education

Material Information

Chemical engineering education
Alternate Title:
Abbreviated Title:
Chem. eng. educ.
American Society for Engineering Education -- Chemical Engineering Division
Place of Publication:
Storrs, Conn
Chemical Engineering Division, American Society for Engineering Education
Publication Date:
Annual[ FORMER 1960-1961]
Physical Description:
v. : ill. ; 22-28 cm.


Subjects / Keywords:
Chemical engineering -- Study and teaching -- Periodicals ( lcsh )
serial ( sobekcm )
periodical ( marcgt )


Chemical abstracts
Additional Physical Form:
Also issued online.
Dates or Sequential Designation:
1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-
Numbering Peculiarities:
Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.
General Note:
Title from cover.
General Note:
Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
01151209 ( OCLC )
70013732 ( LCCN )
0009-2479 ( ISSN )
TP165 .C18 ( lcc )
660/.2/071 ( ddc )

UFDC Membership

Chemical Engineering Documents


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Graduate Education

can be found on

page 369.

Chemical Engineering Education
Department of Chemical Engineering
University of Florida Gainesville, FL 32611
PHONE and FAX: 352-392-0861

Tim Anderson

Phillip C. Wankat

Carole Yocum

James 0. Wilkes, U. Michigan

William J. Koros, University of Texas, Austin

E. Dendy Sloan, Jr.
Colorado School of Mines

Pablo Debenedetti
Princeton University
Dianne Dorland
University of Minnesota, Duluth
Thomas F. Edgar
University of Texas at Austin
Richard M. Felder
North Carolina State University
Bruce A. Finlayson
University of Washington
H. Scott Fogler
University of Michigan
William J. Koros
University of Texas at Austin
David F. Ollis
North Carolina State University
Angelo J. Perna
New Jersey Institute of Technology
Ronald W. Rousseau
Georgia Institute of Technology
Stanley I. Sandler
University of Delaware
Richard C. Seagrave
Iowa State University
M. Sami Selim
Colorado School of Mines
Stewart Slater
Rowan University
James E. Stice
University of Texas at Austin
Donald R. Woods
McMaster University

Chemical Engineering Education

Volume 34

Number 4

Fall 2000

304 Teaching Cellular Automation Concepts Through Interdisciplinary
Collaborative Learning, Joseph J. Biernacki, Jerry B. Ayers
316 Incorporating Chemical Process Miniaturization into the ChE Curriculum,
Frank J. Jones, Bill B. Elmore
320 Yield, Selectivity, and All That,
Ronald W. Missen, William R. Smith
328 Solving Differential Equations with Maple,
Venkat R. Subramanian, Ralph E. White
346 Bioinformatics, Genomics, and the Chemical Engineer: A Perspective,
Vassily Hatzimanikatis, David Collins, Shawn Lawrence, Samuel Browning,
Kelvin H. Lee
350 A Web-Based Course in the Fundamentals of Microelectronics Processing,
Sanjit Singh Dang, Raymond A. Matthes, Christos G. Takoudis
362 Chemical Engineering Debates, J.M. Ottino, J.S. Dranoff

290 Information Technology and ChE Education: Evolution or Revolution?
Thomas F. Edgar

296 A Project-Based Spiral Curriculum for Introductory Courses in ChE:
Part 2. Implementation, Anthony G. Dixon, William M. Clark, David DiBiasio

310 Low-Cost Experiments in Mass Transfer: Part 7. Natural Convection Mass
Transfer on a Vertical Cylinder with Sealed Ends,
M.M. Zaki, I. Nirdosh, G.H. Sedahmed, M.H.I. Baird

326 Is Technology a Friend or Foe of Learning? Richard M. Felder, Rebecca Brent

338 Calculating Minimum Liquid Flowrates: New Method for Rich-Phase Gas
Absorption Columns, Simon M. Iveson
344 Guiding Principles for Teaching: Distilled From My First Few Years of
Teaching, Carolyn W. T. Lee

356 The Honors in the Major Program: A Tool for Enhancing Excellence in ChE
Students, Sharon G. Sauer, Pedro E. Arce

366 A Thermodynamics Problem with Two Conflicting Solutions, Erich A. Miller

325 Positions Available
337 ASEE-ChE Division Awards
343 Book Review

CHEMICAL ENGINEERING EDUCATION (ISSN 0009-2479) is published quarterly by the Chemical Engineering
Division, American Society for Engineering Education, and is edited at the University of Florida. Correspondence
regarding editorial matter, circulation, and changes of address should be sent to CEE, Chemical Engineering Department,
University of Florida, Gainesville, FL 32611-6005. Copyright 2000 by the Chemical Engineering Division, American
Society for Engineering Education. The statements and opinions expressed in this periodical are those of the writers and
not necessarily those of the ChE Division, ASEE, which body assumes no responsibility for them. Defective copies replaced
if notified within 120 days of publication. Write for information on subscription costs and for back copy costs and
availability. POSTMASTER: Send address changes to CEE, Chemical Engineering Department., University of Florida,
Gainesville, FL 32611-6005. Periodicals Postage Paid at Gainesville, Florida.

Fall 2000

re lecture



Evolution or Revolution?

University of Texas Austin, TX 78712

he digital revolution driving societal change is as
significant as the invention of the printing press or
the Industrial Revolution.1" Throughout the world,
information technology (IT) and telecommunications are in-
creasing the flow of information, expanding the possibilities
for collaboration across distances. The pace of change is
accelerating in virtually every field of human endeavor. As
an example, consider the impact of the World Wide Web in
just the last three years. Universities are now confronted
with a rapidly changing environment and a growing realiza-
tion that ignoring change is no longer an option. The chal-
lenge facing higher education is to prepare for an uncertain
future and to provide a technology-rich environment where
students can obtain the continuously changing knowledge
and skills needed to shape that future.[2] Academic institu-
tions will need to offer instructional and support services
that are more oriented to the student's desire to access such
information at any time and from anywhere.
Over the next decade, many universities will broaden their
current student clientele to include degrees, courses, certifi-
cations, and training all made more easily available and
customized through information technology. Competing for
students, faculty, and especially financial resources in this
environment will require a richer vision of education and a
restructuring of the organizations, strategies, and policies
required to achieve it. Table 1 illustrates some of the para-
digmatic changes that have begun to occur.
The expectations and needs of incoming students for digi-
tal facilities and curricula are being shaped by a world of
pervasive microprocessors and telecommunications that is
foreign to the formative education experience of most fac-
ulty and administrators. Duderstadt"'3 has suggested that 21st
century university students will be different than the ones we

have previously enrolled. The new digital generation is not
intimidated by computers, demands interaction, views learn-
ing as a plug-and-play experience, won't read a manual but
learns through experimentation, and may not learn best
through the linear seriatim process. In fact, their brains may
be wired differently, at least in a neural sense.
Over the next ten years, as personal computers, fiber op-
tics, and digital networks expand into homes and businesses,
new students will expect the ubiquitous availability of infor-
mation technology in higher education. There will also be
new technologies available, such as wireless, handheld de-
vices (digital assistants); household LANs, including audio,
video, and appliances; integrated voice, data, and video net-
works (the telephone is an extension of your computer);
voice communication with computers; and 3-D representa-
tion of visual humans (avatars) in customer service.141
These changes are indicative of the increased levels of
disintermediation that humans may prefer vs. interaction
with another human, as long as the quality of service is the
same. The meteoric rise of in the book (and
now video and CD) market is one important sign of chang-
ing consumer preferences, with autos, drugs, insurance, cloth-
ing, travel, and computers and accessories next on the list. A

Thomas F. Edgar is Associate Vice Presi-
dent of Academic Computing and Instruc-
tional Technology Services at the University
of Texas at Austin. He received his BS in
chemical engineering from the University of
Kansas and his PhD from Princeton Univer-
sity. For the past 29 years he has concen-
trated his academic work in process model-
ing, control, and optimization. He has coau-
thored two textbooks and over 200 articles
and book chapters.

Copyright ChE Division of ASEE 2000

Chemical Engineering Education

... ignoring change is no longer an option. The challenge facing higher education
is to prepare for an uncertain future and to provide a technology-rich
environment where students can obtain the continuously changing
knowledge and skills needed to shape that future.1

Old Paradigm
Take what you can get
Academic calendar
University as a city
Terminal degree
University as ivory-tower society
Student: 18 to 25 years old
Books as primary medium
Student as a cost factor
Competition is other universities
Student as a responsibility
Delivery in a classroom
Bricks and mortar
Single discipline
Technology as an expense

New Paradigm
Courses on demand
Year-round operations
University as an idea
Lifelong learning
University as partner in society
Cradle to grave (K to Gray)
Information on demand
Alumni as lifelong revenue resource
Competition is everyone
Student as a customer
Delivery anywhere
Clicks and mortar
Market funded
Technology as differentiator

certain percentage of people will still prefer to go to a book-
store, browse, and drink Starbucks coffee, but clearly not
everyone will behave the same. So why do we expect higher
education to be immune from these trends? The sugges-
tion here is that education may be offered in several
forms, letting the customer (the student) decide how edu-
cation will be acquired.

Technology-enhanced learning environments can be ac-
tive agents that interact with students, expand the informa-
tion horizons of students, and enable effective interactions
across both time and distance. Use of such systems in teach-
ing and learning is growing rapidly. In such environments a
computer presents and combines text, graphics, audio, and
video, with links and tools that let the user navigate, interact,
create, and communicate. This technology can interact with
students in new ways, e.g., give students experiences through
simulations of logical and physical systems.

Changing Educational Paradigms Due to
Information Technology

Fall 2000

In the traditional teaching approach, a human instructor
fulfills several roles. He/she assists in the acquisition and
structuring of information, primarily through organized lec-
tures where the instructor interacts with a group of students.
Experience with processes relevant to the course is typically
obtained either through outside assignments that are evalu-
ated via the student products or through supervised laborato-
ries where the students are guided through the steps of the
processes by instructors. Interaction of instructors either with
individuals or with small groups can spark the insights that
allow information to grow into knowledge. Alternatively,
information technology can play a significant role in assist-
ing in the presentation and acquisition of information, rein-
forcing it, and in leading students through the processes of
structuring of information into knowledge.
Human instructors typically fulfill the roles discussed above
because traditional information media (books, printed mate-
rial, etc.) are essentially passive. Information technology can
implement active agents. An active agent not only presents
information but also interacts with the student to evaluate
his\her levels of understanding with appropriate responses.
Information technology systems can present information and
its structure with much of the richness of human instructors
through the use of multimedia technology
Excellent teachers use varying lecture styles that actively
engage students in the learning process. Information tech-
nology also allows a pure lecturing format to be replaced by
an integrated lecture/laboratory situation. In this mode, the
instructional material is presented on the computer with the
conceptual elements explained and supplemented by the
instructor's lecture. At the end of the presentation, a labora-
tory exercise is executed on the computer under the supervi-
sion of the instructor to give experience in application of the
concepts or processes. This approach is embodied in the
studio-teaching method developed recently at Rensselaer
Polytechnic Institute.[5] Other teaching models are being
pursued by many universities, e.g., those projects funded by
the Pew Foundation (
To make this example more concrete, consider a chemical
engineering example in a separations course. Suppose the
topic of instruction is the impact of operating variables in a
distillation column. The lecturer presents the concepts, fol-
lowed by demonstration of the equations and simulation
results, perhaps augmented by McCabe-Thiele plots. The

students immediately prepare examples, following the pre-
sented directions and using laptops they bring to class or
with shared workstations in the classroom. This cycle may
be repeated several times in a given lecture. This interactive
mode of intermingled lecture and laboratory has a very high
reinforcement value. The computer system is used to me-
diate the rate at which information is presented to each
individual student.
Note that the lecturer is not removed from the cycle. While
the laboratory exercises are going on, the lecturer can move
among the students, looking over their shoulders and serving
as an advisor and facilitator. Teaching and learning becomes
more a one-on-one or small-group exercise and less a re-
mote-lecture exercise. The instructor is transformed from
being a "sage on a stage" to a "guide on the side." This
integrated lecture/laboratory mode of instruction is now be-
ing used in industrial training, particularly in the software
industry. Learning and cognitive studies have shown defini-
tively that personalized learning via immediate feedback has

a significant impact, as shown
in Table 2. The range of cogni-
tion and retention actually
achieved depends upon nature
and tone of remediation.
There are wide-ranging de-
bates in academia about the role
of technology in education; you
see conflicting views in almost
every issue of the Chronicle of
Higher Education. Faculty are
taking sides in the debate; for
example, see the report by the
University of Illinois System
port), written by a committee

Retention for Different
Learning Strategies
(Source: Andersen

Teaching others
Learn by doing
Discussion group

chaired by Professor John Regalbuto, a chemical engi-
neering professor.
There is one irrefutable conclusion regarding the use of
technology: namely, anything that enhances the learning
process improves quality, but quality should be determined
by both learners and instructors. Integrating information
technology into instruction at most universities will require
careful planning, experimentation, and assessment over the
next ten to twenty years. This will not be an easy process.
Many faculty members and administrators believe that gradual
evolutionary change over a period of thirty years or so is the
best path to transformation.
Responding to evolutionary technological change may be
an inefficient way to manage a comprehensive university,
however. Simply adding technology in an incremental way
to curriculum and instruction will not save instructional costs
even though it may slightly enhance the classroom experi-


ence. The traditional modes of teaching and research will
still dominate ten years from now, but changes at the perim-
eter can and should occur. Sharing of electronic instructional
and educational materials over the web may offer some
economies. The CACHE Corporation is developing a web
site for chemical engineering educators to facilitate such
sharing (
Technology-enhanced learning may figure prominently in
addressing new issues that education customers are now
raising, e.g., requests for post-baccalaureate professional edu-
cation, access to asynchronous Internet-based learning, dis-
tance education, wider ranges of student preparation, certifi-
cation of practical specialized competencies, collaboration
in education and research, and competition with private or-
ganizations entering the education market. In order to change
the current teaching and learning environment, universities
and departments will need to
Reconsider faculty rewards and incentives (e.g., promo-
tion and tenure, compensation), especially given the extra
time and effort required to develop courses enhanced
with technology
Find resources to provide technical support (infrastruc-
ture), classroom facilities and training/release time to
faculty who want to adopt new methods
Find the appropriate balance between productivity
increases, faculty overloads, and quality of education,
including the incorporation of off-campus students into
residential classes.
The University of Texas at Austin just completed a year-
long study on such issues; see evpp/planning/ITCC/TELC.html>

Distance education is the combination of technology-based
education with technology-based delivery of a complete
course. Distance education has been defined as any formal
approach to learning in which a majority of the instruction
occurs while educator and learner are at a distance from one
another. Hardly a week goes by that there is not an article
appearing in most newspapers or magazines about this sub-
ject. Distance education has been hyped as the quick fix for
many of the problems in higher education, with the vague
promise of delivering a higher quality of education at a
lower cost. Expensive regular faculty will not be needed-
they will be replaced with part-time adjunct faculty, such as
the University of Phoenix is doing. But there needs to be a
more thoughtful approach to distance learning at most uni-
versities. Simply putting textual information on a web
page is not an improvement in quality of education; it is
comparable to correspondence courses as they have been
traditionally offered.
Some aspects of using distance learning even for residen-
tial students are appealing."16- Anyone who has listened to a

Chemical Engineering Education

Pavarotti CD but never heard the great tenor in person has certainly received a certain level
of enjoyment (and perhaps inspiration) from this great singer. So those who suggest that
real education can only be delivered in the traditional face-to-face mode are overstating
their point. In addition, it is well documented from teaching evaluations that not all classes
taught at a university are of uniformly high quality. A student sitting in the last row of a
large lecture class of several hundred students is certainly "at a distance" from the
instructor. We ought to be seeking ways to enhance the classroom experience for residen-
tial students through use of distance-educational tools.
One model of where distance-learning concepts could be used would be in a hybrid
form, in which the web is used to deliver fundamental information that would otherwise be
contained in a lecture.?8' This approach could be valuable in teaching introductory math
and science courses (for example) to large numbers of students who may have quite
different backgrounds, thus allowing students to move ahead at different speeds.
Distance education does appear to be a good fit for continuing education, where highly
motivated, mature students will make sure they learn what is needed. Having such classes
offered at a convenient time and place (asynchronous mode) is critical for professionals
with full-time jobs who need to update their skills and knowledge base in response to
changes in the economy. This nontraditional student population is rapidly growing in the
U.S. The availability of streaming media technology (audio and video) over the Internet
will eventually make delivery of courses to personal desktop computers a reality. The faculty
member's office then becomes the studio, which will make educational delivery at lower cost
than with the interactive television mode currently employed at many universities.

The digital science and information revolution is rapidly transforming the ways faculty
and students conduct research, collaborate, solve problems, and disseminate knowledge.
The integration of computers, telecommunications, audio, video, multimedia, and other
digital technologies creates a worldwide information environment that can be accessed
easily from the laboratory, office, field, and home. In this new environment, supervision of
dissertation or thesis research is sometimes carried out over a distance, where e-mail and
videoconferencing augment face-to-face meetings between a research student and mem-
bers of the supervising committee. Multi-university research projects can be coordinated
via weekly videoconferences, such as those in the supercritical fluids research center
sponsored by the National Science Foundation. On the other hand, research using labora-
tory experimentation requires a structured environment (e.g., well-equipped laborato-
ries). Hence it is difficult to perform experimental research at a distance, although
sharing of expensive specialized equipment through virtual connections will become
more common in the future.
Experimentally oriented faculty in the future will rely more heavily on computational
and visualization tools, possibly with less intensive capital investment in equipment and
laboratory facilities. Experimentation is relatively more expensive to perform with today's
stringent safety requirements. Clearly, information technology can impact the kinds of
faculty hired by chemical engineering departments, and most faculty will need to stay up-
to-date in some aspects of IT in order to carry out cutting-edge research. This suggests
a greater need for training of faculty, not only in instructional tools but also in
research tools that are IT-based. One other impact of IT is the need to form interdisci-
plinary groups on campus in order to attack important, multifaceted problems that
involve advanced computing.
Most U.S. universities are now members of Internet 2, which provides high bandwidth
capabilities (over 100 times as fast as today's commodity Internet) for faculty research and
distance education. This includes, for example, digital libraries with audio and video

. .. those

who suggest
that real

can only be

in the

mode are

their point...

of streaming


(audio and
video) over
the Internet



delivery of
courses to


a reality.

Fall 2000

content, collaboration and immersion environments, remote
monitoring of experiments, and data-intensive applications

In the past it was common for a researcher to spend many
years working on some difficult or esoteric problem, un-
aware that someone else was interested in the same thing.
Collaborative tools now allow people to share results more
regularly, on a daily or even hourly basis.
The global networking of faculty groups
can be called a collaboratorry" a merg-
ing of the words collaboration and labo- The hig
ratory. No longer is it a requirement that a textbook
department maintain multiple experts in a collective
single field so colleagues can have face- five bo
to-face interaction in a specialized research back
area. In some cases, a faculty member's certainly
ties to the collaborator, which is global for stud(
in its makeup, may be stronger than the electron
connections to his or her own department in t
or university. Independent scholars can
use recently developed tools to see new Of col
patterns and trends, not just the facts but reading is
the contexts in which they arise, and share cultural a
the results on-line without the normal jour- the touch t
nal publication delay. One such book is t
collaborator is in the area of molecular expel
modeling ( There
are a number of agency-sponsored
collaboratories on topics such as AIDS
research, molecular structure, NMR spectrometry, health
care, and space physics.
As such collaboratories develop, a logical extension will
be holding technical conferences on-line, with keynote lec-
tures via webcasting, paper presentation and discussion, and
even virtual vendor expositions. The Internet World Con-
gress on Biomedical Sciences, held in December of 1998,
was just such an experimental meeting and was termed a
success. But virtual meetings will not totally replace face-to-
face experiences such as the AIChE annual meeting; they
can, however, augment these regular events (hopefully with
reduced cost, including a minimal registration fee). Key
lectures could be webcast and played at an individual's
convenience. The electronic format will make such meetings
even more accessible to faculty and graduate students with
limited travel budgets. The question-and-answer sessions in
technical sessions could become even more lively, since
there is no time constraint of the Q&A period run as a

Electronic publishing and the gradual replacement of pa-

per-based modes for carrying out the business of higher
education will certainly impact faculty and students in the
future. We have seen the first wave of construction of digital
libraries; both the American Chemical Society and Elsevier
are being fairly aggressive in moving toward complete digi-
tization of scientific and engineering journals, while AIChE
has proceeded more cautiously. Clearly, a user of the litera-
ture would find having access to the text of journal articles
on one's desktop to be a tremendous productivity tool. The
value of such digital libraries is greatly en-
hanced by having the ability to access refer-
ences cited in the article, but this will be
ost of problematic until the "back issue" problem
nd the in technical journals has been solved. There
-ight of have been some experiments on the eco-
in a nomics of old-journal digitization, such as
are JSTOR, a digital conversion project for a
entives group of humanities and social sciences jour-
to use nals funded by the Mellon Foundation. This
a involves scanning the contents of paper jour-
nals, and then libraries licensing the con-
ure. tents of JSTOR, at a price that is incremen-
book tal to the cost of the paper-based journal.

sity libraries to

Commercial publishers, however, are not
inclined to sell only the electronic version at
a lower cost and give up current income
levels with the standard subscription pack-
age. Because faculty and students demand
the electronic version when it is available,
this means the costs of journal subscriptions
will continue to rise, causing most univer-
cancel some fraction of their subscriptions

each year in order to hold their budgets roughly constant.
The irony of this situation is that faculty and graduate stu-
dents who provide most of the papers for a typical research
journal must pay page charges to the publisher, who then
sells that same material back to the university libraries. This
is a cost cycle that clearly will be restructured in the future,
and already a number of professional groups are beginning
to take action on the problem.
I believe that with the help of electronic commerce (i.e.,
credit cards processed over a secure connection), a transac-
tion-based system where users pay for access to journals
might make more sense in the future. Such fees might run
from $200 to $400 per year for an active researcher. This
usage-metered pricing is similar to the plan proposed by
music publishers in dealing with technology changes such as
MP3 music on the Internet.
The World Wide Web offers a nearly free mechanism for
publishing, where faculty and graduate students can publish
preprints of their research work (but not copyrighted papers
that appear in journals). This could include MS and PhD
dissertations. But ACS journals currently refuse to accept

Chemical Engineering Education

,h c
s al
e we
ic n

a social and
activity, and
md feel of a
art of the

articles that have previously appeared on the web. It is
interesting that chemists have adopted such a stringent view,
when almost all of the other sciences have encouraged pre-
print publishing on the web. The differences seem to be
cultural. In fact, Los Alamos National Laboratories operates
a server for the physics community (Journal of High Energy
Physics) to encourage the exchange of information.
Other societies, such as ACM, are devising mechanisms
for handling submission, reviewing, and final publication of
computer-science manuscripts using a totally electronic ap-
proach and are making original versions of the papers avail-
able for a limited period of time. In 1999, the National
Institute of Health proposed using the Internet to dissemi-
nate papers generated by biomedical researchers who have
received NIH grants, thus saving millions of dollars in page
charges and journal subscriptions.
In the competition for leading papers, however, faculty are
circumspect about submitting articles to a new journal with-
out a track record, whether it is electronic or not. Because of
economic constraints, few university libraries are willing to
add new subscriptions, so the electronic journals must sur-
vive on individual subscriptions. New, unproven journals
are unlikely to be included in various scientific indexes, such
as that of Institute for Scientific Information (ISI); Chemical
Abstracts tracks about thirty electronic-only journals. Na-
tional efforts by AAUP and the Association of Research
Libraries may lead to breakthroughs in the electronic pub-
lishing morass. Over one hundred research libraries have
formed SPARC (Scholarly Publishing and Academic Re-
sources Coalition) to increase market competition and re-
duce journal prices.
Electronic books may eventually replace part of the tradi-
tional book publishing market. The high cost of textbooks
and the collective weight of five books in a backpack are
certainly incentives for students to use electronic media in
the future. Of course, book reading is a social and cultural
activity, and the touch and feel of a book is part of the
experience. Computer companies, however, are developing
devices that feel like a book but permit downloading of
material from the web. So one electronic book could eventu-
ally access a large store of books. Two products (Rocket
Book and Softbook) are now available, and technological
enhancements will make them more user-friendly and cheaper
in the near future. Both of these ventures are backed by an
array of publishers. Carrying two pounds of electronics in-
stead of twenty pounds of books or magazines would be
attractive, assuming you can obtain the on-line version of
such material. Eventually you will be able to download such
content from the web.
As a coauthor of two chemical engineering textbooks with
mainline publishers (McGraw-Hill and Wiley), I believe
there is an opportunity to change the paradigm of textbook
publishing over the next five to ten years, where the contents

Fall 2000

of a book would be entirely on-line. This would be advanta-
geous for incorporating interactive exercises based on simu-
lation in an integrated way, converting the traditional text-
book into courseware that is much more comprehensive than
the hard-copy versions used today. Faculty can selectively
incorporate parts of on-line books into their courses. While
most universities have taken a position of benign neglect
regarding faculty writing textbooks (and have not claimed
intellectual property rights), that view may change when
courseware becomes the product, since such a package may
be more valuable to a university. One electronic textbook
under development that bears watching is on molecular mod-
eling (see

I have attempted to paint a picture of how universities will
be undergoing change during the next ten to twenty years
and how that will affect faculty and student processes. The
compressed time scales that we are experiencing due to
technological advances are referred to as "Internet Years,"
versus the normal metrics for time. While it is useful for
academicians to cling to the fact that in many ways universi-
ties have not changed much in the past two hundred years,
clearly universities must adapt to maintain their core values.
External forces may cause the evolution to in fact become a
revolution. There are many possible paths to the future, and
universities need to explore various options and to be proac-
tive in carrying out experiments and innovation, rather than
merely hoping these external forces will go away.

This paper is taken from the Chemical Academy Lecture
presented by the author in April, 1999, at the University of

1. Negroponte, N., Being Digital, Knopf, New York, NY (1995)
2. Dolence, M.G., and D.M. Norris, Transforming Higher Edu-
cation, Society of College and University Planning, Ann
Arbor, MI (1995)
3. Duderstadt, J.J., "Can Colleges and Universities Survive in
the Information Age?" pp. 1-25 in Dancing with the Devil,
Educause/Jossey-Bass Publishers, San Francisco, CA (1999)
4. Dertzoukis, G., What Will Be, Harpers, New York, NY (1998)
5. Wilson, J., "Distance Learning for Continuous Education,"
Educom Review, 32(2), 12, March-April (1997)
6. Bothun, G.D., "Distance Education: Effective Learning or
Content-Free Credits?" Cause-Effect, 21(2), 28 (1998)
7. Petre, M., L. Carswell, B. Price, and P. Thomas, "Innova-
tions in Large-Scale Supported Distance Teaching: Trans-
formation for the Internet, Not Just Translation," J. Eng.
Ed., p. 423, October (1998)
8. Poindexter, S.E., and B.S. Heck, "Using the Web in Your
Courses: What Can You Do? What Should You Do?" IEEE
Control Systems, p. 83, February (1999)
9. Wilkinson, S.L., "The Electronic Frontier," C&EN, p. 38,
June (1999) C


e, curriculum




Part 2. Implementation*

Worcester Polytechnic Institute Worcester, MA 01609

his series of papers reports the development, deliv-
ery, and assessment of a project-based, spiral cur-
riculum for the first sequence of courses in chemical
engineering. The program is a significant restructuring of
the traditional chemical engineering curriculum. Tradition-
ally, a compartmentalized course sequence designed to build
a conceptual foundation is taught during the sophomore and
junior years, followed later by more integrated projects. Our
new curriculum requires students to learn and apply chemi-
cal engineering principles by completing a series of open-
ended design projects starting during their sophomore
year. The new curriculum is spiral in that students' un-
derstanding of basic concepts is reinforced by revisiting
them in different contexts with ever-increasing sophisti-
cation. A more detailed explanation of the concepts and
curriculum design behind this effort was described in the
first paper in this sequence.1]
In this paper we will present the details of the spiral
curriculum, together with illustrative examples of some of
the projects used in the novel curriculum.

Worcester Polytechnic Institute (WPI) has a non-tradi-
tional academic-year structure, consisting of four seven-
week terms. A fifth term is taught during the summer, but
our spiral curriculum is restricted to the regular academic
year. Students take three courses during each term, usually
meeting every day and averaging 5-6 contact hours per week,
with differing proportions of lecture and conference time.
While this structure, more modular than traditional pro-
grams, allows greater flexibility in allowing students to

pursue opportunities for study abroad and/or to carry out
off-campus senior- and junior-year projects, it results in
an intensive and fast-paced learning environment within
a given course.
The conventional sophomore year at WPI for chemical
engineers addresses concepts that require an understanding
of equilibrium but not rate. It consists of the sequence of
chemical engineering courses: stoichiometry and material

William M. Clark is Associate Professor of
Chemical Engineering at WPI. He holds BS and
PhD degrees in chemical engineering from
Clemson University and Rice University, respec-
tively, and has 13 years of experience teaching
thermodynamics, unit operations, and separa-
tion processes. His educational research focuses
on developing and evaluating computer-aided
learning tools.

David DiBiasio is Associate Professor of Chemi-
cal Engineering at WPI. He received his BS, MS,
and PhD degrees in chemical engineering from
Purdue University. His educational work focuses
on active and cooperative learning and educa-
tional assessment. His other research interests
are in biochemical engineering, specifically bio-
logical reactor analysis.

Anthony G. Dixon is Professor of Chemical
Engineering at WPI. He holds a BSc degree in
mathematics and a PhD degree in chemical en-
gineering from the University of Edinburgh. His
research has included development of interac-
tive graphics software to aid in teaching process
design and mathematics to engineers.
Copyright ChE Division of ASEE 2000

Chemical Engineering Education

* Part 1 appeared in CEE, 34(3), p. 222 (2000)

and energy balances, classical thermodynamics, solution ther-
modynamics, and staged (equilibrium) separation processes.
Concurrently, the students take an advanced chemistry se-
quence of physical chemistry, organic chemistry (two
courses), and an organic chemistry laboratory. Their third
course each term varies according to background, but usu-
ally includes differential equations and lib-
eral arts/social sciences electives. The fresh-
man year consists of a calculus sequence, The i
an introductory chemistry sequence, phys-
ics, and some humanities electives. The con-
ventional sophomore chemical engineering when f
sequence was taught by four different fac- tha
ulty (including one of the coauthors) in the needed
years during which the spiral curriculum The stud
was offered in parallel. The content of the at a 1
courses is reflected by the course text- eit
books,[2-51 which are widely used and which experi
were also used in the spiral curriculum (note confide
that the book by Wankat was used in the enon
first-year offering and the book by Seader
to a.(
and Henley was used in the second-year mat
offering). For the spiral curriculum, the stu-
dents purchased all their books at the start appro
of the sequence instead of course-by-course, T
as in the traditional sequence. instruct
To construct topic sequencing and levels,
we itemized specific skills and content for faculty
the four traditional courses in the sopho- to an
more year. Over 135 items were identified sl
for the four courses in addition to general
skills such as report writing, oral communi-
cation, etc. We then prioritized the topics

and skills and rearranged them into a four-course spiral
sequence. The first spiral course introduced key concepts
from all four traditional courses at an introductory level
(Level 1). Subsequent spiral courses revisited the same fun-
damental concepts with increasing levels of complexity (Lev-
els 2-4). More details on this phase of the curriculum devel-
opment are presented in Part 1 of this series.11
The instructional components of the spiral curriculum con-
sisted of formal lectures, homework, problem-solving ses-
sions, group projects, and exams. Students were evaluated
on both individual work (homework, exams) and group-
based assignments (projects). The projects were used to
motivate and focus the study of the topics described in Part
1, but since they could not include all topics it was necessary
to supplement them with formal lectures within which some
topics were discussed exclusively. Typically, individual work
counted for 60-70% of the term's grade, with group-project

Fall 2000

d th
ite s

work making up the remainder.
The curriculum was delivered by the three coauthors, with
a teaching assistant and a peer learning assistant (PLA) who
assisted in facilitating group dynamics. Each project, with
the associated lectures, classes, labs, homework, and exams
was taught by an individual faculty member. Thus, since the
students participated in three projects
each term, they were taught by all three
duction faculty each term, although not always
s occurred in the same order.
ty judged In year one, 16 students were randomly
dents selected from a class of approximately
e topic. 56, whereas in year two the experimen-
were not tal section was 20 students from a class
of 46. Students were not allowed to self-
select for the experimental group. Any
their student who did not wish to participate
e or their would have been allowed to return to the
was high traditional section prior to the beginning
or them of the academic year. Transfer out of the
r new experimental section was allowed at
Iat the any time, but students could not elect
ite time. to transfer into the sequence. We did
the not replace dropouts after the begin-
1 activities ning of the academic year.
structured, A mixture of instructional methods was
used in the new curriculum in order to
tempting address the diverse learning styles of the
ate the students. We used in-class active-learn-
nts' ing problem-solving sessions and mini-
ds. sessions, combined with lectures,
throughout the year. During the course
of each project, class time and home-
work assignments were aimed at helping the students ac-
quire the required fundamentals on a "just-in-time" basis
through an assortment of channels, including multimedia
computer instructional modules, lectures, workshops, read-
ing assignments, and student discovery from experimenta-
tion and/or the literature. Homework problems were as-
signed that assisted the students with calculations and con-
cepts that they were about to need for the project. After each
project period of two to three weeks, an exam was given that
covered concepts from the lecture material, project material,
in-class work, and homework.
The "just-in-time" approach to the projects had to be mod-
erated with an appreciation of the maturity level of the
students, especially in the early part of the curriculum. The
introduction of new topics occurred when faculty judged
that students needed the topic. The students were not at a
level where either their experience or their confidence was


high enough for them to ask for new material at the appropri-
ate time. Thus, the instructional activities throughout a project
were quite structured, with the faculty attempting to antici-
pate the students' needs.
The curriculum featured several laboratory experiences,
associated with the projects and described in the following
section. In addition, use was made of computer-aided in-
struction (CAI) and multimedia tools. Two interactive multi-
media disks were developed for this curriculum by one of
the authors (WMC) on the properties of pure fluids and on
chemical reaction equilibria.[6] In addition, learning tools
from the University of Michigan"71 were used. The reaction-
equilibria CAI disk was used in combination with a project,
and the others were used as supplements to lecture. A por-
table collection of notebook computers facilitated in-class
problem-solving and computer skill-building sessions.
Students were assigned to four-member cooperative learn-
ing groups and were reassigned to new groups every seven
weeks. The assignments were made randomly, but adjust-
ments were made to distribute the strongest students evenly
across the groups. Some group meetings were held during
class time, but most were held outside of class. All group
members received the same group project grade.
As an illustration, a generic timetable used for a project is
shown in Table 1. Several variations on Table 1 were used,
depending on the project, but the essential elements are
included there. The class met every day (as is typical for
WPI courses), and one class per week lasted for a two-
hour period, allowing more extended in-class participa-
tion. In the example shown, Tuesday was the double
period, so there could be lecture and in-class problem
solving on the same day.
To show how the instructional sequence was structured
around the project, we will here consider a specific example
and refer to Table 1 for comparison. In the middle of Level
2, we asked the students to design a new steam power plant.

Students determined heat and work requirements in a boiler,
a condenser, a turbine, and a pump. They determined the
thermal efficiency of the cycle, compared it to a Carnot
cycle, and determined ideal and lost work for various com-
ponents. Early in Level 1, the students were exposed to
material balances on reactive processes and to energy bal-
ances without reaction. In this Level 2 project, they made
material and energy balances on a reactive system, combus-
tion in the power plant boiler. In Level 1, they also studied
PVT properties of pure fluids and performed energy bal-
ances on steady-flow devices in a refrigeration cycle. Here
in Level 2, they combined It and 2nd law analysis for power
cycles (and refrigeration cycles in a subsequent project). The
steam power-plant project also required them to consider
environmental issues. A proposed catalytic reduction pro-
cess for removing 1000 ppm NO from the boiler flue gas by
reaction with NH3 was analyzed. This twist on the typical
power-plant problem required the students to think about
heat exchange to cool the flue gas and at the same time
vaporize and heat the ammonia that was stored as a liq-
uid under pressure.
The student teams were confronted with this project be-
fore they had learned all the fundamentals required to com-
plete it. Because it was still early in the sophomore year, this
project had an itemized list of intermediate deliverables and
an associated timetable, as shown in Table 1. On day one,
the project was assigned and groups brainstormed about how
to approach it and determined what they did and did not
know about how to solve it. A brief memo report (Part 1)
analyzing the methane combustion reaction in the boiler was
due a few days later. A second memo report (Part 2) and a
brief oral report on the thermal efficiency of the power plant
were due a week later. A third memo report discussing the
entire project, including an open-ended call for suggested
improvements to the process, was due at the end of the two-
and-a-half-week period.
At the beginning of this project, reading assignments, a

Generic Timetable for a 3-Week Project Segment of the Curriculum

Week Monday Tuesday Wednesday Thursday Friday

1 Introduce Project; Lecture; Homework due; Part 1 Due In-class problems
Brainstorm In-class problems In-class MathCAD Lecture; discussion

2 Homework due; Lecture; Lecture Part 2 Due In-class problems
Lecture In-class problems Oral reports;

3 Homework due; Exam

Project Due
Start new project

Chemical Engineering Education

Spiral Curriculum Projects by Level

Level 1
Dehydrogenation of ethanol to acetaldehyde This project introduces students to a simple acyclic process with
chemical reaction and separation.' Material balances are made, using the reaction stoichiometry with one main
reaction and two side reactions, to calculate reaction conversion and yield. Concepts of separation are introduced
(flash, absorption, distillation) and simple splits are calculated without any equipment design being attempted.
Methylene chloride recovery This project addresses the recovery of a solvent from the air above a parts-
washing tank by using a refrigeration unit to cool the air stream and condense the solvent. Students use ideas about
partial saturation to calculate the composition of the air, then use energy balances to analvye the refrigeration
process to determine circulation rates of refrigerant and cooling water, and the compressor power requirement.
Chemical process tank explosion An indoor surge tank contains a multicomponent mixture at an elevated
pressure. Students are presented with a scenario in which the pressure control fails and the tank vents directly into
the room. They are asked whether an explosion will occur in the presence of an ignition source. They are required
to calculate multicomponent VLE over a given temperature range to obtain the vapor composition and check
explosion limits.

Level 2
Design of plant-scale distillation column This is a laboratory project in which students conduct a preliminary
design for an ethanol/water staged distillation column. They obtain experimental values for stage efficiency from
an existing laboratory column. Their analysis includes number of stages and feed location, condenser and reboiler
loads, tray diameterfrom flooding curves, and a preliminary cost estimate.
Steam power plant The design of a new steam power plant is proposed. Students use thennochemistry to
calculate the flue-gas composition and heat of combustion of the fuel. They use thermodynamic principles of flow
processes to analyze the turbine to obtain ideal work and then use efficiencies to obtain actual work. They address
the environmental issues and perform energy balances for a heat exchanger to cool the flue gas prior to a proposed
catalytic reduction process.
Ammonia process synthesis Students perform material balances on a process with recycle." An energy
balance for a turbine is carried out to obtain work available that involves real gas calculations and use of residual
properties. An isothernal staged gas absorber is designed, using Henry's law. A staged distillation columnn.
including the refrigeration loop on the condenser, is designed, forcing students to revisit these concepts.

Level 3
Mixer feed strategy for isothermal operation This project involves the feed, in six separate hourly additions,
of a solid to water. The mixing tank is heated/cooled at a constant rate. The objective is to operate as nearly
isothermal as possible. Students use heats of solution data in combination with material and energy balances to
calculate heats of mixing and determine the amount of solid that can be added each hour.
Design of a pressure-swing distillation sequence The student teams are given VLE data for the methyl acetate/
methanol azeotrope system at 1 atm. They are asked to choose a higher pressure, corresponding to a different
azeotrope composition, and to design a pressure-swing distillation sequence to separate the components, using
methodspresented in the texts.14"' They fit VLE data at I atm under low-P assumptions to obtain activity coefficient
correlations, then use these correlations together with high-Pfugacity coefficients and the Poynting correction to
predict the VLE at the higher pressure.
Liquid-liquid extraction The ternary system acetic acid/water/ethyl acetate is studied. A laboratory experiment
is performed using a two-stage crossflow extraction, and students compare their measured results to predictions
obtained using a constant distribution coefficient model. After verifying the LLE model, a multistage crossflow
extractor is designed for industrial conditions.

Level 4
Catalyst regeneration A catalyst regeneration process is described in which a catalyst that has deactivated due
to the deposition of carbon on it is regenerated by passing a stream of hydrogen over the catalyst at high
temperature. Students are asked how long it will take to remove 90% of the deposited carbon under given operating
conditions. This requires them to calculate the equilibrium product composition for a single reaction, and integrate
their results into material balances for the regeneration process. They are also asked to consider using steam for
catalyst regeneration, leading to an analysis of multiple reaction equilibria.
Batch distillation Students design and test an experimental project related to the basics of multistage batch
distillation. The student group plays the role of the teaching team for the course. They have available a glass
distillation column in the unit operations laboratory with provision for adjusting the reflux ratio. Unsteady
material and energy balances are used to analyze column behavior.
Simulation of vinyl chloride process A steady-state simulation of a vinyl chloride processis5 is performed using
the ASPEN PLUS flowsheeting package for combined material and energy balances. Students are given a
relatively detailed flowsheet for the process and an approximate material and energy balance table, under some
simplifications such as perfect splits. They have to decide what level of detail to put into the flowsheeting model and
perform a more rigorous simulation.

Fall 2000

lecture, homework, and in-class prob-
lems were given on combustion reac-
tions. A portion of a class period was
used for hands-on computer calcula-
tion of heats of reaction with tempera-
ture-dependent heat capacities using
Mathcad. As the project progressed,
lectures and assignments were given
on the main ideas of heat effects of
reactions, entropy and the second law,
power cycles, thermodynamics of flow
processes, refrigeration, and funda-
mental property relations. Some of
these topics had been briefly intro-
duced earlier in the curriculum, and
some were revisited in later projects-
for example, refrigeration. Frequently,
lectures gave the essentials of a subject
only, with further material being intro-
duced through the in-class problems and/
or discussion, which forced the students
back to their texts or to the instructor for
more explanation or information.

The exam at the end of this project
period covered heat effects for indus-
trial reactions and 1V and 2nd law analy-
sis for flow processes, including power
and refrigeration cycles. It was conve-
nient to have the project final report
due on the day after the exam. This
gave students the opportunity to pol-
ish the reports on an evening when
nothing new was assigned due to the
transition between topics and in-


Brief descriptions of all the projects
used in the course are presented in
Table 2, ordered by level and in chro-
nological order within each level.
Three of the projects involved labora-
tory work, while one short one used
ASPEN PLUS in a simulation. Sev-
eral of the projects contained compo-
nents of engineering design. On aver-
age, the students completed the
projects, including a team-written re-
port, in two weeks, although the labo-
ratory-based projects sometimes re-
quired a little longer.
Four of the projects, one from each


Figure 1. (Level 1, Project 1) Process flowsheet for ethanol
dehydrogenation to acetaldehyde.

level, have been selected for more detailed discussion
below to illustrate both how they were integrated into the
curriculum and the evolution of the students' abilities
throughout the year.

> Ethanol dehydrogenation
(Level 1, Project 1)
This was the first project that the students saw in the new curricu-
lum. Since they had no chemical engineering background at that
stage, the project was very simply stated and all engineering jargon
had to be explained. They were given the process flowsheet de-
picted in Figure 1, and the functions of all blocks representing
pieces of equipment were carefully explained. Written descriptions
of the process chemistry and the process itself were provided. The
flow rates of most of the streams were provided, and the primary
project goal was to work backwards to determine the conver-
sions of the ethanol to the desired product acetaldehydee) and
to the by-products (acetic acid, ethyl acetate). Some secondary
goals were also set, requiring the students to work with mole/
mass conversions, make some further balances to scale up
production, and calculate the splits obtained in the separations
equipment for the various species. Although the process itself
did feature a recycle stream, by giving the flow rates for it the
material balances reduced to those for an acyclic process.

As the project teams considered this task over two weeks,
they received more formal instruction on units, analysis and
measurement, non-reactive material balances, material balances
on multi-unit systems, stoichiometry, reactive material bal-
ances, and combustion. The material was quite structured to
respond directly to what they needed to complete the assign-
ment-they were not expected to "dig it out" for themselves at
this stage. The project introduced them to a variety of chemical
engineering terms, allowed them to see the work they were
doing in the context of a complete, although much simplified,

process, and helped to motivate the study of the introductory
1 Ammonia synthesis
S (Level 2, Project 3)
The students were at a quite different stage at the start of
this project, almost exactly halfway through the year. They
had covered material and energy balances, 1s" and 2"d law
thermodynamics, and could design and analyze flashes and
staged distillation columns as well as power and refrigera-
tion cycles. They had seen recycle on a small scale, for
7 individual equipment and power cycles, but had not yet
attacked a complete flowsheet with recycle. They were still
using ideal-gas concepts or steam tables for properties, and
Raoult's law for phase equilibria.
The function of this project was to introduce the students
to a moderately complex recycle process, as shown in Fig-
ure 2. The process included recycle of unconverted reac-
tants, purge, and make-up streams, and recycle of absorber
cooling water. The process was gas-phase, running at 225
bar, except for the absorber (40 bar) and distillation column
(1 bar). This high-pressure process motivated the introduc-
tion of real gas behavior, although as the gases were mostly
hydrogen and nitrogen, the actual deviations were not large. In
addition to performing a complete material balance, the students
were asked to design several aspects of the equipment. They were
asked to evaluate the possibility of replacing the expansion valve,
VAL-1, by a turbine to recover useful work, and to determine the
cooling duty required for the cooler, CLR-2, in that case. They had
performed such calculations before in the ideal-gas case, but were
now instructed to use the Lee-Kesler generalized correlations to
calculate residual properties. The presence of the absorber moti-
vated introduction of some lecture material on the design of this
equipment, which provided an opportunity to revisit the operating-
line concepts seen before in distillation design and to contrast the
use of Henry's law for gas-liquid equilibria with that of Raoult's
law for vapor-liquid equilibria. Their last task was a design of the
distillation column and the refrigeration cycle used to condense the
ammonia in the overhead, which again forced them to re-use prior

Figure 2. (Level 2, Project 3) Ammonia synthesis process flow

Chemical Engineering Education

Figure 3. (Level 3, Project 2) Methyl acetate/methan
separation by pressure swing distillation (schematic .
drawn from Reference 5).

material, this time in the context of a complete process. Thus, this
project introduced a significant element of the spiral nature of the
curriculum, requiring several of the skills previously acquired, but
either in extended form or in a different setting.

> Pressure-swing distillation
(Level 3, Project 2)
The material with which students have the most difficulty during
their first set of courses is usually solution thermodynamics. The
concepts are more abstract than material balances, for example, and
the frequently heard lament in the traditional
section is "What's the use of a fugacity any-
way?" or similar not-so-polite expressions.
We found it difficult to break up the material / ve
usually taught in this course or to introduce
much of it earlier when the conceptual abili-
ties of the students would be even less devel- Condenser
oped. Our approach, therefore, was to leave
the material relatively intact, but to motivate
it with the project shown in Figure 3 and to
emphasize the practical use of the ideas be- Ra
fore introducing the theoretical background. spi
From their previous work on distillation,
including a laboratory project using the etha-
nol-water system, the students understood
the difficulties of separating azeotropes. Some
methods of dealing with this were briefly
reviewed, and the focus was put on pressure-
swing distillation. In this method, two col-
umns operating at different pressures were
used. The azeotropic composition was pres-
sure-dependent, and advantage could be taken
of this to effect a complete separation. These Reboller S
methods were well-described in the class
texts.4'51] Following a review of minimum-
boiling and maximum-boiling azeotropes, the
Bottoms Prod
students were given VLE data for the system sample Port
of interest, at 1 atm. Concurrently in their
classroom exercises, they were asked to use Figure 4. (Level 4,
Raoult's law to fit xy-data for the ethanol- gu 4- F"e ;

water azeotropic system, to convince them that more
sophisticated methods were needed. The Wilson equa-
tion was introduced, and they had to use it to fit the
supplied data, under low-P assumptions. They picked
a higher pressure to operate the second column and
used the constants for the Wilson equation to predict
the activity coefficients at the new conditions. In ad-
dition, they were told that they could not assume low-
P for their new conditions and that they had to use the
fugacity coefficient corrections and Poynting factor.
When they had the new xy-data (see Figure 3 for an
example), they tested their understanding of McCabe-
Thiele methods by re-using them (more spiral struc-
ture!) to design the columns for the azeotropic system
separation, which required them to work in terms of
the less volatile component.

Concurrently with their work on this project, the
class was introduced to the usual definitions and deri-
vations of solution thermodynamics in formal lecture and class
exercises. They accepted these concepts more readily with the
project and a realistic application as motivation.

> Batch distillation
(Level 4, Project 2)
Level 4 represented the end of the sophomore year. By this time,
the students had gained considerable maturity and had acquired a
wide range of skills. Topics covered in this level included transient
material balances (batch distillation) and combined material and
energy balances (psychrometric charts, hu-
midification and enthalpy-concentration dia-
grams). We felt they were ready for a very
open-ended, somewhat different type of
T project.
coolingg Water In We asked them to design a project that might
water Out T be used in subsequent course offerings. The
project had to include topics that were cur-
rently under study, could include anything ap-
rlable propriate from earlier in the year, and had to
hitter use the batch distillation column available in
the unit operations lab. The project not only
provided a chance to "think outside the box,"
but also provided an application of transient
balances and revisited distillation for the fourth
time in the academic year. After designing
their project, the student teams had to test it in
the laboratory and modify their design ac-
The lab column is a two-story high, 11
Di e bubble cap, glass column with a steam reboiler
team Product and capability for operating at variable or con-
stant external reflux ratios from 1 to 40. Early
Condensate in Level 2, students performed energy bal-
ances, equilibrium, and efficiency calculations
uct using this column operated at total reflux. They
were familiar with column operation, data tak-
ing, sample analysis, and safety procedures. A
Project 2) Pilot sketch of the column is shown in Figure 4.

Fall 2000

000 020 040 060 080 1 00



ac s a on column.


Proper project design required each student group to develop
educational objectives, write a scenario providing context for their
experiment, and specify deliverables from the fictitious students
who might use the project in subsequent years. This "design your
own project" assignment had the potential for groups to incorporate
lots of material from earlier projects, including nonideal thermody-
namics, McCabe-Thiele analysis, column efficiency calculations,
and energy balance (heat loss) calculations.
Our experience from two implementations of the "design your
own project" was somewhat mixed regarding the results. Reports
from the first set of student teams had very creative and original
scenarios and showed that most teams spent many hours testing
their projects. But their educational goals were somewhat naive,
limited only to current course topics, and the reports were poorly
written. We modified our own assignment description and pro-
vided a little more guidance for the second implementation. The
results of this change were much improved, and we were generally
quite pleased. Substantial incorporation of appropriate material
from earlier in the year was not evident, however, even in the best
groups. Reasons for this result are currently under evaluation and
will be reported in Part 3 of this series.

One of the primary aims of the new curriculum was to
develop the students' ability to work on open-ended projects,
to work in teams, and to communicate the results of their
work. In order to evaluate the success of the curriculum in
achieving these goals, relative to the traditional curriculum,
a design competition was held near the end of the academic
year. Student teams were assigned a difficult open-ended
chemical engineering design project requiring integration of
material covered during the year. They were asked to de-
velop a process flowsheet and present their analysis of a
process for the production of 106 lbmol/hr of 99% pure
formaldehyde. They were given the reaction
CH30H t> CH20 + H2
and told that a catalyst was available that was active enough
to attain reaction equilibrium for stated conditions of tem-
perature and pressure. They were also told that a membrane
process was available that completely separated H2 from any
stream at any T, P. Physical properties information was
supplied. Students were asked for a quantitative analysis of
their proposed process and the associated material balances.
A sketch of the type of flowsheet we anticipated the teams
would come up with is shown in Figure 5. Students were
expected to recognize the need to separate the product form-
aldehyde from unreacted methanol and to recycle the metha-
nol. They had to decide whether to do this by flash or
staged distillation and then design the unit. They needed
to make reaction equilibrium calculations to obtain the
composition of the product stream from the reactor and
perform a material balance with recycle once they had
the equilibrium conversion.
Twelve students from the new, spiral-taught section (inter-
vention section) and twelve students (volunteers) from the

... we anticipate that otherfaculty can step
into the spiral curriculum with relative ease. The
preparation time would certainly be no worse
than for any new teaching assignment
in a conventional course.

Find optimal T and P for reactor. Determine which is preferred,
flash drum or distillation column.

Figure 5. Problem for design competition.

traditional section (control section) participated in the com-
petition. The students from each section were randomly
subdivided into three teams of four students each. Students
were paid $50 each for participating, and (to increase moti-
vation) a $50 prize was awarded to each member of the
teams with the best designs. We awarded a prize to the best
effort from the three intervention-section teams and also to
the best effort from among the control-section teams, so that
students competed only within their own section. Winners
were determined by independent judges. The competition
took place during a single two-and-a-half hour period, com-
prised of two hours of work and two ten-minute presenta-
tions. Three rooms were used, with one team from each sec-
tion in each room. Both the students' working sessions and
their oral presentations were videotaped for later analysis.
Three professional chemical engineers from academia and
industry served as judges for the competition. These judges
had no connection with either the intervention or the control
sections of the course and did not know the identity of any of
the students or from which section the various groups came.
Judges were instructed to view the videotape of the students'
oral presentations and to rank the work of the six groups
based on the quality of the technical content, disregarding
presentation style in their rankings.
The judges unanimously ranked the students from the
intervention section in the top three positions, with students
from the control section ranked in the bottom three posi-
tions. This evaluation showed that the students in the inter-
vention section had an increased ability to apply chemical
engineering principles to the solution of integrated design
problems. Our own viewing of the videotapes showed that
the intervention-section teams made more progress on the
analysis, successfully integrated material from different ar-

Chemical Engineering Education


eas of chemical engineering, and gave more consideration to
alternative solutions.

We learned several lessons from the development of the
project-based spiral curriculum structures. The integration
of project-based activities involved considerable work for
the faculty, not least because of the degree of inexperience
of the students at this stage of their development. The degree
of open-endedness and type of project that could be given to
seniors in their design project would be overwhelming for
sophomores. Instead, it is necessary to orchestrate the projects
in a way that will lead the students in the desired direction
and to coordinate them very tightly with more formal mate-
rial and resources. The concept of spiraling all four courses,
although appealing, needed tempering. It became apparent
in structuring the content that the majority of the material
and energy balance content still has to appear early in the
year, while the more difficult solution thermodynamics can-
not be effectively introduced early in the course and should
wait until after the classical material has been presented. We
ended up with a structure that was more parallel in con-
cept-it seems to be very effective to teach applied material
alongside the more abstract or theoretical material. This
seems to happen naturally for the material-balances course,
but it requires positive efforts to integrate solution thermo-
dynamics with applications in separations.
The preliminary assessment results showed that the new
curriculum met the educational objectives that we had in
mind when it was developed. The technical proficiency of
the group of students under the spiral curriculum was at least
equal to, if not better than, that of the traditional group. Their
attitudes toward chemical engineering and teamwork were
better. Their teamwork and communication skills were bet-
ter than those of the traditional group, and they showed
enhanced ability on "real" projects. More extensive assess-
ment results based on the complete two-year experimental
program, plus follow-up on the groups after their sophomore
experience, will be reported in Part 3 of this series.
The new spiral curriculum could be readily adapted to the
traditional semester system, either whole or in part. The
most obvious translation would be to cover our first two
levels during the fall semester and our next two during the
spring semester, thus combining two seven-week terms into
one fourteen-week semester in each case. This would re-
quire introduction of staged separations earlier than is often
the case and separately from the rate-based separations of
the mass-transfer operations course popular in many schools.
Our sequence of material and energy balances followed by
classical thermodynamics followed by solution thermody-
namics is fairly standard. If this amount of restructuring
were not feasible, then it would be possible to import some
of the projects into existing courses and use them as motivat-
ing exercises, although the benefits of ongoing teamwork

Fall 2000

might be reduced. Also, if separations applications could not
be used in conjunction with thermodynamics, then one of the
advantages of the approach would be lost.
Now that the structure and projects have been put in place,
we anticipate that other faculty can step into the spiral cur-
riculum with relative ease. The preparation time would cer-
tainly be no worse than for any new teaching assignment in a
conventional course. New faculty could also bring different
projects to the curriculum, corresponding to their own expe-
riences and expertise. A major difference from the faculty
point of view is that such an assignment is for an entire
academic year rather than for a single semester or term.
Involvement with the course is ongoing throughout the year
due to the need to coordinate with other teachers, but is
relatively low-level when others are actually involved in the
classroom. One advantage is that when a faculty member
needs to be out of town on other scholarly activities, it is
relatively painless to find a substitute!

The authors would like to thank the Department of Educa-
tion for support of this work under the Fund for the Improve-
ment of Post-Secondary Education (FIPSE), Award No.
P116B60511. Thanks are also due to Kevin O'Connor and
Lisa Comparini of the Clark University Jacob Hiatt School
of Psychology for helpful discussions, and to Jack Ferraro
and Douglas White for their help with the laboratory

1. Clark. W.M., D. DiBiasio, and A.G. Dixon, "A Project-Based,
Spiral Curriculum for Introductory Courses in Chemical
Engineering: Part 1. Curriculum Design," Chem. Eng. Ed.,
34(3), 222 (2000)
2. Felder, R.M., and R.W. Rousseau, Elementary Principles of
Chemical Processes, 2nd ed., John Wiley & Sons, New York,
NY (1986)
3. Smith, J.M., H.C. Van Ness, and M.M. Abbott, Introduction
to Chemical Engineering Thermodynamics, 5th ed., McGraw-
Hill, New York, NY (1996)
4. Wankat, P.C., Separations in Chemical Engineering: Equi-
librium Staged Separations, Prentice-Hall, Upper Saddle
River, NJ (1988)
5. Seader, J.D., and E.J. Henley, Separation Process Prin-
ciples, John Wiley & Sons, New York, NY (1998)
6. Clark, W.M., "Learning Chemical Reaction Equilibria on
CD-ROM," in Interactive Learning: Vignettes from America's
Most Wired Campuses, David G. Brown, ed., Anker Publish-
ing Company, Inc., Bolton, MA (2000)
7. Fogler, H.S., S.M. Montgomery, and R.P. Zipp, "Interactive
Computer Modules for Undergraduate Chemical Engineer-
ing Instruction," Comp. Appl. in Eng. Ed., 1(1), 11 (1992)
8. CACHE Process Design Case Study Series No. 3, "Design of
an Ethanol Dehydrogenation Plant," by L. Biegler and R.R.
Hughes, edited by M. Morari and I.E. Grossmann, 1985
CACHE Corp, Austin, TX
9. CACHE Process Design Case Study Series No. 2, "Design of
an Ammonia Synthesis Plant," by S.G. Bike and I.E.
Grossmann, edited by M. Morari and I.E. Grossmann, 1985
CACHE Corp, Austin, TX D

- ., -~-- I----.-----.. j..



Through Interdisciplinary Collaborative Learning

Tennessee Technological University Cookeville, TN 38505

he application of cellular automaton to simulate trans-
port and reaction phenomena is not a conventional
topic in most chemical engineering curricula, even at
the graduate level. These techniques, however, can be pow-
erful tools for the simulation of processes involving com-
plex boundary conditions, multiple phases and phase trans-
formations, and multiple reactions where traditional con-
tinuum approaches are limited, difficult to solve, or even
intractable at this time.
The objectives of the course were to teach graduate and
undergraduate students about cellular automaton in a col-
laborative learning environment. Students working together,
learning from each other, and teaching each other may be
one of the most effective ways to promote student learning.
The study of cement hydration and microstructure develop-
ment was used as a basis for the course, drawing on the
interdisciplinary nature of concrete materials research to
create cross-disciplinary collaborative learning teams that
include undergraduate and graduate students.
This report is based on the experiences and activities of
twelve students, including three senior undergraduates ma-

Joseph J. Biernacki received his BS from Case
Western Reserve University (1980) and his MS
(1983) and Doctor of Engineering (1988) from
Cleveland State University. He is currently As-
sociate Professor at Tennessee Technological
University where he pursues his research inter-
ests in synthesis and processing. He is also
interested in research on engineering educa-
tion and dedicates this paper in memory of his
colleague and coauthor Jerry B. Ayers.

Jerry B. Ayers received his Ed.D in Science
Education from the University of Georgia (1967).
He served as Associate Vice President for Re-
search at Tennessee Technological University
from 1994 until his unexpected death in Sep-
tember, 1999. Prior to that he held positions as
Director of the Center of Excellence for Teacher
Education Evaluation, Associate Dean of the
College of Education, and various faculty ap-
pointments at TTU.
Copyright ChE Division of ASEE 2000

joring in chemical engineering, five master-level (two civil
engineering and three chemical engineering), and four doc-
toral students (two civil, one chemical, and one mechanical)
in a course titled "Interdisciplinary Studies in Multi-Scale
Simulation of Concrete Materials." A brief course descrip-
tion and assessment of outcomes is given.
In an effort to facilitate learning, a collaborative environ-
ment was created in which students were not only encour-
aged to work together but were also placed in setting wherein
they could build teaming and collaborative skills. Having
MS graduate and undergraduate students in the same class-
room is not unique; bringing together interdisciplinary teams
that include PhD, MS, and undergraduate students, how-
ever, is less common, and assessing the efficacy of such a
course is even less known.
Combining students across the vast gap between PhD
studies and the undergraduate course of study creates several
unique problems, including adequate differentiation between
requirements and disparity in technical maturity between
students. Introducing an interdisciplinary environment fur-
ther complicates the problem. While this project does not
attempt to prove or disprove the proposed benefits of having
students vertically and horizontally integrated in this way, it
does propose and demonstrates the use of assessment tools
to track student satisfaction, impressions, and performance
to ensure continuous improvement and viability of the ap-
proach. It is hoped that this introductory paper will help
others to construct and test similar models that will eventu-
ally lead to new and better learning environments for both
graduate and undergraduate students.

Since cellular automaton is not a common topic in most
chemical engineering curriculum, a few notes are provided
here with several references. Originally introduced by von
Neumann and Ulam in an effort to simulate biological pro-
cesses such as reproduction, cellular automata are algorithms
that define the evolution of states for a system of cells
wherein a cell's state is dependent on the state of neighbor-

Chemical Engineering Education

__ W Im- -_ __ 1 r- l

i ---- q I l I II I IA I J I

i-- r--- r-


Grawtmue 0EdtHWairka

ing cells.'" Cellular automaton involves dividing a system (a
two-dimensional plane, for example) into cells. Then, for
each cell, defining a rule or a global set of rules for all cells
that govern state transitions from one automaton cycle to the
next, from one time or system state to the next. For example,
the state transition rule for a binary one-dimensional au-
tomaton might simply be to change a
cell's state from zero to one when- cyck
ever the sum of the cell's state and initial condition 0
its neighbors' states is equal to one. 1
A system of cells based on this state
transition rule propagates from au- 4
tomaton cycle-to-cycle, as shown in 5
Figure 1. It can be seen that these 6
rules and the initial and boundary 7
conditions chosen in Figure 1 pro- 8
duce a stable cycle of cell states after 9
five automaton cycles. The ability of 10
cellular automaton to generate com- 12
plex behaviors based on simple rules 13
has been used by many researchers. 14
In the physical sciences phase trans- 15
formation as well as chemical reac- 16
tion and transport processes have
been modeled and the mathematical Figure 1. Propagation
interpretation of automata have been automaton rule that c
extensively studied.1[2 Brieger and (black) to one (white)
and its neighbor's static
Bonomi offer a derivation used in this and its neighbor's stat
course that illustrates the connection
between probabilistic state transitions and the finite difference
solution of the one-dimensional transient diffusion equation.'3'
Bentz[41 and Bentz, et al.,'[5 at the National Institute of
Standards and Technology (NIST) have pioneered and de-
veloped an extensive system of models based on digital
image-based processing to simulate cement hydration and
microstructure development. Cellular automata are used to
subdivide the complex multiphase system of cement par-
ticles into cells, each of which are addressed with phase
descriptors. Virtual particle systems are constructed that sta-
tistically mimic real particles. Appropriate automaton rules
describing dissolution, diffusion, and reaction are applied,
and the virtual microstructure is permitted to evolve. Charac-
teristics of virtual hydration (such as heat evolution) as well as
properties of virtual hydration product (such as porosity and
permeability) have been extensively studied and reported.i6'7

Engineering education is faced with new pressures and
challenges from industry and accreditation boards to incor-
porate team-oriented interdisciplinary experiences into the
course of study. This current state of heightened awareness

of c
f th
es is

is putting pressure on departments and colleges to find ways
to create curricular opportunities for students to engage in
such experiences. Hicks and Katz[18 list interdisciplinary in-
teraction among five increasing trends in modern research,
while Gulden['9 and Mason["p1 report improved retention of
knowledge and preparedness for advanced studies when such
approaches are used. Dahir reports
that 80% of employers feel that be-
ing able to work in teams is an im-
portant attribute in a new graduate,
yet only 25% of survey respondents
felt that new graduates are ad-
equately prepared to work in
teams.' Findings of the SUCCEED
Engineering Coalition suggest that
vertical integration, i.e., freshmen
and seniors working together, is also
an important aspect of engineering
education.[121 They also conclude
that "the future...may lie more
in...horizontal...components than
in...vertical," observing that inter-
disciplinary integration may be as
important as vertical integration. Fi-
ell states for the cellular nally, a flood of recent attention is
ges the state from zero being given to peer-oriented teach-
e sum of the cell's state ing and learning and collaborative
;equal to one. learning (sometimes referred to a
cooperative learning)."3-161
Collaborative learning refers to the trend toward student-
centered rather than teacher-centered pedagogy wherein stu-
dents not only work in teams but are also encouraged to
teach and learn from each other. "7'"81 Wankat and Oreoviczl"81
offer a summary of models to structure teams, nurture team-
work, and promote peer teaching and learning. From these
models, the informal cooperative learning group and the
formal cooperative learning group were adopted. The infor-
mal model helps students learn to collaborate through short
in-class team (group) activities coached by the instructor in a
controlled setting. The formal learning group model is in-
tended for long-term tasks and project assignments, much of
which is to be completed out of class and without the
instructor's immediate participation. The present course uses
the concepts of both vertical and horizontal integration and
collaborative learning in a research-based environment. Fur-
thermore, students more advanced in their academic train-
ing, PhD-seeking students, were placed in mentoring roles.

Objectives The course had two objectives: 1) introducing
students to digital image-based simulation using cellular

Fall 2000

automata, and 2) preparing students to meet the demands of
research-oriented careers in which they will formulate rel-
evant research questions, devise methods to investigate their
questions, work in teams or small interdisciplinary groups of
technical professionals who are at varying levels in their
professional development, and report on their findings.
* Scope In this course the students learn the basics of
cement chemistry and the processes that describe hydration.
They then learn to define automaton rules and to write code
to simulate dissolution, diffusion, reaction, and precipitation
for a two-dimensional, two-solid-phase system in a single
fluid media. Concurrently, students learn to use research
codes that are capable of simulating the full spectrum of
cement phases in three dimensions and are challenged to apply
their new knowledge to conduct a research-based term project.
* Assessment Strategy Assessment tools were selected to
provide pre-course information, midterm information (for-
mative), and post-course information summativee).
1. Student journals (diaries) were used as a real-time ongoing
feedback and feed-forward mechanism for course improve-
2. A pre-course self-assessment of knowledge was used to
find out what students believed they knew and what their
expectations were. This form of assessment is sometimes
called a background knowledge probe (reported by Millis
and Cottell[161 and Angelo and Cross'19) and was used to
establish an effective starting point for the course.
3. A pre-course test of cognitive knowledge was used to
measure what students actually knew and to establish a
quantitative knowledge baseline.
4. A midterm assessment of student satisfaction and reactions
to the course was used for ongoing course improvement.
5. A post-course test of cognitive knowledge was used to
measure what students had learned relative to the pre-
course test of cognitive knowledge (item 3 above).
6. An end-of-term (post-course) assessment of student
satisfaction and reactions to the course was made.'s18
The results of the post-course test, in combination with
assessment of performance on course requirements, was used
to evaluate student
learning and to gauge TAI
satisfaction and reac- Weighting Facti
tions to the course. All
assessment tools, ex- Requirement
cept for the pre- and Participation in class, scheduled group laborato
post-test, were de- Proposal writing: MS (pre-proposal); PhD (full
signed and interpreted Homework (individual assignments)
by an impartial evalu- Written paper: BS (lab report); MS (thesis-styl
Final presentation
ator other than the in- Final esea
Final exam
structor. A website Coursejoumal
containing the assess- Total
ment instruments as

well as a course syllabus and extended reference bibliogra-
phy is available.[201

Assessment standards were developed for each student
level. An attempt was made to align these standards with the
ABET 2000 Criterion 3.[21]
Outcomes and Requirements (what each student was
expected to achieve and do) Outcomes for all students were
mapped to the ABET Criterion 3b (ability to design and
conduct experiments), 3d (ability to function in multi-disci-
plinary teams, 3e (ability to identify, formulate, and solve
problems), 3g (ability to communicate effectively), 3i (rec-
ognize need for and ability to engage in life-long learning),
and 3k (ability to use engineering tools). In addition, an
ability to provide guidance and mentoring for junior-level
researchers was an outcome applied to PhD students only.
Table 1 lists the course requirements and relative weight
for each element for the different student levels. Notable
differences include the form or type of final written report.
Undergraduates were required to prepare a laboratory-report
style paper, MS students a thesis-style report, and PhD stu-
dents a publication-style paper. This was done to give each
level of students the opportunity to write and be reviewed at
what should be their appropriate level. Similarly, MS stu-
dents were required to write a pre-proposal at the beginning
of the term, reflecting on what the team would do for the
semester, and PhD students were required to prepare a more
detailed proposal at the end of the term, reflecting on the
team's findings. While undergraduates were not required to
complete this element, they were asked to read and, where
possible, to provide feedback to the authors, thereby offering
the undergraduates exposure to the proposal process.
Mapping Outcomes and Requirements (how outcomes
were measured) Each requirement was further mapped to
one or more outcome (see Table 2). The key to using the
map is to establish rubrics for each requirement that are valid
measures of the crite-
E 1 rion mastery. An ex-
r Assessment ample is included here
to clarify how the pro-
BS MS PhD cess works.
nd team activities 5% 5% 5% Consider the rather
sal) NA 5% 10% difficult-to-assess out-
50% 25% 20% come Criterion 3i, the
D (publication-style) 20% 25% 25% ability to recognize
20% 25% 25%
NA 10% 10% need for and engage in
5% 5% 5% life-long learning. This
100% 100% 100% criterion was mapped
to BS requirements 3,

Chemical Engineering Education

ors f<

ries, a

:d); Ph

4 j IL

4, and 7-homework, written paper, and the course journal,
respectively. Arguably, one might agree that one measure of
the ability to engage in life-long learning might be to ob-
serve how well a student is able to gather and assimilate
information from a variety of resources, such as the library
and the internet. In this way, the quality of the literature
review would be viewed as one measure of Criterion 3i,
linking the written paper requirement to the outcome through
a specific rubric. Similarly, connections between other select
requirements and their mapped outcomes were made to es-
tablish the students' level of mastery of each. One final note is
that while an outcome was established regarding mentoring
abilities for the PhD students, no requirements were mapped to
it. As such, no element of the grade reflected this outcome.

To facilitate learning, course materials were broken into
three parts: 1) learning about cellular automata, 2) learning
about digital image-based simulation of concrete materials,
and 3) doing research. Homework assignments were designed
to enable students to learn automata concepts in a step-wise
manner through programming assignments while introducing
them to existing research codes in a parallel set of assignments.
"Learning About Cellular Automata (Building Cellular
Automata Codes)" was a series of eight assignments in which
students were required to write their own code to simulate a
simple two-dimensional, two-particle reaction-diffusion pro-
cess. Students were instructed in the use of VisualBasic and
wrote code to both simulate the process and visualize the
automata in real time.
A parallel set of assignments, "Learning About Digital
Image-Based Simulation of Concrete Materials (Learning to
Use the NIST Modeling Software)" introduced the students
to existing research codes developed by NIST researchers.
This assignment set stepped students through the process of
building virtual three-dimensional microstructures from real
two-dimensional electron micrographs and running hydra-

Assessment Mapping of Outcomes and Course

Assessment Tools (Requirements)
Outcome BS Requirement MS Requirement PhD Requirement
Criterion 3b 7,4,1 1,2,4,7 1,2,4,7
Criterion 3d 1,7 1,2,7 1,2,7
Criterion 3e 3,4,5 2,3,6 2,3,6
Criterion 3g 1,2,4,5,7 1,2,3,4,5,6,7 1,2,3,4,5,6,7
Criterion 3i 3,4,7 3,4,7 3,4,7
Criterion 3k 3,4,5 3,4,5 3,4,5
Mentoring NA NA NA

tion simulations on the microstructures they constructed. Par-
allel lessons covered topics such as the mathematical basis of
automata and the statistics of digital image-based processing.

Team-oriented research was the primary focus of the course.
Numerous researchers suggest strategies for forming teams.
These include using personality-type indicators to help es-
tablish teams, [22231 random selection,1241 and choosing teams
to be academically balanced.i3'251 In this course it was im-
portant to have interdisciplinary teams as well as vertically
integrated teams. The small student body, however, limited
the possible combinations of individuals. Teams were formed
by placing one PhD student on each of four teams and then
identifying team members by interest and academic rank.
The PhD-level graduate students were placed in a mentoring
and leadership role. The hope is that students will not only
learn technical content but also critical process and profes-
sional development skills through this teaming and peer-
oriented mentoring.
A student-interest questionnaire was used that asked a
series of five simple questions in an effort to develop an
interest profile of the group (i.e., What technical areas of
your discipline are you most interested in?). The majority of
responses were very helpful in determining the composition
of the student body. From that information, teams were
formed and appropriate topics identified for the research.
Team compositions and topics are summarized in Table 3.

No traditional text exists from which the course could be
taught. Resource materials were assembled from sources
including Garboczi, Bentz, and Snyder's Electronic Mono-
graph on Simulation of Concrete Materials[261 and Bentz's
guide to using the NIST models.1271

Teams and Research Topics

Team Topic/Title
1 Characterization of Blast Furnace Slag
and Blast Furnace Slag Reactions for
Use in Blended Slag-Cement Systems
2 Kinetics of the Reaction Between Fly
Ash and Calcium Hydroxide with
Microstructural Applications
3 Determination and Evaluation of
Thermal Conductivity of Neat
Cements and Concrete
4 Estimation of Transport Properties of
Virtual Concrete Microstructure with
Fractal Aggregate Distribution

Team Composition
Undergraduate; Chem Eng
MS Student; Chem Eng
PhD Student; Chem Eng (audit)
Undergraduate; Chem Eng
MS Student; Chem Eng
PhD Student; Civil Eng
MS Student; Civil Eng
MS Student; Civil Eng
PhD Student; Mech Eng
Undergraduate; Chem Eng
MS Student; Chem Eng
PhD Student; Civil Eng

Fall 2000

* Pre-course self-assessment questionnaire During the
first class meeting, a questionnaire requesting self-rating of
knowledge about the twenty major topics to be included in
the course was administered. The rating scale was 5=Exten-
sive knowledge of subject with no need for further study to
l=No knowledge of topic. Fourteen items received ratings
at less than 2 (Little knowledge of subject; Need extensive
information). There were no differences among the three
groups of students in their mean ratings of each item or their
mean overall ratings.
The students felt they knew the least about content-based
topics such as use of cellular automaton, percolation theory,
and cement hydration. They felt they knew the most about
process elements such as writing a good research proposal or
a good research paper and the role of life-long learning in
research and engineering practice. In addition, the students
were asked to respond to four questions related to why they
enrolled in the course, their learning style, and what they felt
they would learn from the course. The students were inter-
ested in modeling and simulation, some with emphasis on
concrete and related problems. The students hoped to im-
prove their research skills and the majority indicated they
were either visual learners or learned by a combination of
visual and auditory mean. The results of these pre-course
self-assessment questionnaires were used to guide instruc-
tion content and approach.

Merely placing students in teams does not necessarily
create an environment where they will mentor other stu-
dents. To promote peer-oriented learning, several tactics
were used. First, the concepts of peer-oriented collaboration
were articulated during the first week of classes and were
frequently reinforced thereafter. For example, collaborative
learning is not copying from the person most likely to have
the correct answer, but rather having that person explain or
tutor others in the group toward an independent understand-
ing of the subject. Numerous in-class and in-lab team activi-
ties (informal group settings) were scheduled. During infor-
mal group sessions, students were typically instructed to
work in their formal group team. In this way, students had
the opportunity to work as a group under the direct supervi-
sion of the instructor, and the instructor had an opportunity
to observe group dynamics and work toward enabling the
team. During these sessions, tasks such as conceptual algo-
rithm design, coding at the computer, or learning to run exist-
ing software were used as short in-class or in-lab tutorials.
These sessions were used to promote interaction between
introverted team members and to facilitate acquisition of
basic knowledge by having the instructor join teams that

were perceived to need help in either area.1161 On individual
assignments such as homework, students were encouraged
to work together, particularly with team members, and to
learn from each other (formal group settings). In this envi-
ronment, teams were on their own to schedule meeting times
and achieve their goals, and teams frequently reserved time
to meet with the instructor. The instructor also scheduled
meetings at critical checkpoints during the semester, provid-
ing feedback to the teams. Structured team self-assessment
as well as individual self-assessments were used to promote
performance awareness among students and to provide a
feed-forward mechanism for the instructor to monitor team
progress. The self-assessment used also had specific ques-
tions regarding peer-oriented interaction and was used to
gauge the relative amount of collaboration. Finally, peer
review and revising of documents such as proposals and
reports was modeled by the instructor and encouraged be-
tween team members.
WebBoard, an internet-based communications software,
was also used to promote within and between group interac-
tion. Any student could post to the WebBoard course confer-
ence, read, and exchange information.

* Midterm Assessment A midterm questionnaire was ad-
ministered that included ten bipolar statements related to the
course, eleven open-ended phrases the respondents could com-
plete with one of several choices, and four open-ended ques-
Table 4 shows the mean responses to the ten bipolar state-
ments. Since there were no differences across major or de-
gree level, the data were combined. The students felt the
course was about equally divided between a theoretical and
a practical orientation. The lowest mean rating was given to
the requirement of keeping a journal. The students appar-
ently did not understand the reason for the journal nor how

Mean Ratings by Students (N=12)
to Ten Items at Midterm of Course

# Stem Mean
1 Organization of course (Unsuited to objectives 1...6 Well suited) 4.4
2 Work associated with course had (Little relevance 1...6 Great relevance)4.7
3 Working in groups has been (No value 1...6 Great value) 4.7
4 Laboratory work has been (No value 1...6 Great value) 5.2
5 Computer exercises have been (No value 1...6 Great value) 4.8
6 Keeping ajoumal has been (No value 1...6 Great value) 3.8
7 Quality of instruction has been (Poor 1...6 Excellent) 4.8
8 Quality of handouts has been (Poor 1...6 Excellent) 4.4
9 Mixtures of students is (Little value 1...6 Great value) 5.0
10 Orientation of the course has been (Theoretical 1...6 Practical) 3.4

Chemical Engineering Education


to use it in the course. Highest mean ratings were given to
laboratory work and the value of having students at three
distinct academic levels working together. Thus it appeared
that the students had an appreciation for the value of team-
work with individuals from varying backgrounds and de-
grees of preparation.
In response to the eleven open-ended phrases, students
indicated they felt the objectives and plans for the course
were explained and organized and that they were being
stimulated to think and solve problems. The highest overall
ratings were given to questions regarding the willingness of
the instructor to provide help and the
instructor's appreciation of the
student's point of view. The lowest TABLE
ratings were given to questions re- Summary of Pre- a
lated to the practical value of the in- Results Base
formation presented in the course. Objectives of
Again, there did not appear to be any
differences in ratings given by the Degree Level N Mean Pre-Te
three levels of students. Bachelor's 3 6.7

Responses to the four open-ended
questions provided additional insight
into strengths, weaknesses, and
needed improvements in the course
at midterm. Students indicated that a

major strength was the programming and computer skills that
they were learning while the major weakness of the course was
the workload. Yet, in a free-writing question, students stated
that they were "learning through group projects."
* End-of-Term Assessment A questionnaire was adminis-
tered at course completion. The questionnaire included eight
bipolar statements related to the course, five open-ended
phrases that the respondents could complete with one of
several choices, and six open-ended questions.
Responses to the eight bipolar statements were no differ-
ent across major or degree level, and there were no signifi-
cant differences between ratings at the midterm and at the
end of the course. The average score was 4.58/6.00, with the
lowest score being 3.5 for a question related to keeping the
course journal. Other questions were related to course orga-
nization, workload, group work, laboratory work, quality of
instruction, quality of instructional materials, and value of
working with students from other disciplines.
In the five open-ended phrases, students were asked to
indicate their feeling or opinion by checking the appropriate
response for items related to the operation of the course. In
general, the students valued the course and the instructor.
Seven of ten responses said that the team approach to re-
search with students from different disciplines and at differ-
ent levels was a positive point of the course. Again, most
students felt that the workload was excessive.

Responses to six open-ended questions again reinforced
midterm responses to similar questions, showing that the
major strengths of the course were the instructor, working in
teams, the research project, and the challenge of thinking
and problem solving. In general, students endorsed the idea
of having students from varying backgrounds and levels
being brought together. While they perceived a number of
benefits to this approach, their biggest concern was the prob-
lem of scheduling times for group work.
0 Pre- and Post-Test of Cognitive Knowledge A twenty-
item test was constructed around the major objectives of the
course. It included mutiple-choice and
short-answer questions. The test was ad-
5 ministered on the first day of the class
id Post-Test and again on the last day, so a compari-
d on son could be made. All students corn-
Course pleted the instrument at the beginning
of the class, while only the graduate
st Mean Post-Test students completed the post administra-
n/a tion of the instrument. Because of the
13.6 small sample sizes, no results of signifi-
16.0 chance were computed. Table 5 shows a
summary of the results of the test ad-
ministration for those students for which
complete data were available.
Raw scores for students enrolled in the MS and PhD
programs almost doubled from the beginning to the end of
the course. While this is to be expected, the pre- and post-
course test enables quantification of learning. And, while
there is no standard at this time to compare to the relative
pre- and post-test scores, they establish a first data point for
future comparative studies of course outcomes.

The major questions of this study were "Did it make a
difference to have students enrolled in a course who were at
the undergraduate, master's, and doctoral levels?" and "Does
peer-oriented collaboration promote learning in this environ-
ment?" While this study did not attempt to provide a definitive
answer to either question, the instructor was able to bring all
students into the course at their apparent level of learning as
measured by assessment of course requirements. Students felt
that the undergraduates learned from the graduate students,
and in responses to written questions as well as through inter-
views, they indicated a generally positive experience.
While the level of interaction between students varied, and
while this was difficult to measure, one direct indicator was
the log of WebBoard postings. Seventy-eight communica-
tions were posted during the sixteen-week semester. The
majority of these postings were communications between
Continued on page 315.

Fall 2000

Master's 5 7.2
Doctorate 3 8.0

il I i MO. O



W laboratory



Part 7. Natural Convection Mass Transfer

on a Vertical Cylinder with Sealed Ends

Lakehead University Thunder Bay, Ontario, Canada P7B 5E1

Chemical engineers commonly use dimensionless cor-
relations for predicting heat and mass transfer coef-
ficients needed to design heat and mass transfer
equipment operated under natural as well as forced-convec-
tion conditions. This paper describes a simple electrochemi-
cal technique to establish a correlation for natural-convec-
tion mass transfer in which the dimensionless group Sherwood
number (Sh) is expressed as a function of Grashof (Gr) and
Schmidt (Sc) numbers in the form

Sh = (Gr Sc) (1)
Such a condition is useful for predicting the mass transfer
coefficient1] that is needed in the design and operation of
chemical and electrochemical reactors used in conducting
liquid-solid diffusion controlled reactions.
This laboratory experiment introduces chemical engineer-
ing students to the basic theories of mass transfer, dimen-
sional analysis, and electrochemistry, and at the same time
provides training and skills in electrochemical techniques
that are quite important for processes such as corrosion,
electrowinning of metals, electrorefining, electroplating, elec-
troforming, electrochemical machining, electrodialysis, and
effluent treatment for environmental purposes.

Electrolytic cell solutions used for mass-transfer studies
usually contain a certain concentration (Cb) of an electroactive
species (such as Cu2+) and a relatively large concentration of

SDepartment of Chemical Engineering, Alexandria University,
Alexandria, Egypt
" Department of Chemical Engineering, McMaster University,
Hamilton, Ontario, Canada

a supporting electrolyte (such as H2S04). The supporting
electrolyte ionizes

(H2SO4 <--H+ +HS04- -2H+SO42-)

Magdy Zaki is a graduate of Alexandria Uni-
versity and received his PhD in 1991. He worked
as Assistant Professor in Zagazig University,
Egypt, and as Senior Consultant to DANIDA,
Denmark/Env. Affairs Agency, Egypt. He was a
Visiting Scientist at the University of Wiscon-
sin, Madison, and has been a Visiting Profes-
sor at Lakehead University.

Inder Nirdosh received his BSc and MSc in
chemical engineering from Panjab University
(India) and his PhD from Birmingham Univer-
sity (United Kingdom). He joined Lakehead Uni-
versity in 1981, and his research interests are
in the fields of mineral processing and electro-
chemical engineering

G.H. Sedahmed is Professor of Chemical Engi-
neering at Alexandria University, Egypt. He re-
ceived his BSc, MSc, and PhD from Alexandria
University and was a Visiting Professor at the
New Jersey Institute of Technology (1970),
McMaster University (1974-76,1980-82), and .
Lakehead University (1989-93).

Malcolm Baird received his PhD in chemical
engineering from Cambridge University in 1960.
After some industrial experience and a post-
doctoral fellowship at the University of
Edinburgh, he came to McMaster University.
His research interests are liquid-liquid extrac-
tion, oscillatory fluid flows, and hydrodynamic
modeling of metallurgical processes.
Copyright ChE Division of ASEE 2000

Chemical Engineering Education

Figure 1. Apparatus

Figure 2.
(a) Buildup of hydrodynamic and mass transfer boundary
layers along the cathode surface.
(b) Concentration distribution of Cu" at the cathode sur-

Fall 2000

to provide high solution conductivity (low Ohmic resistance,
R,) and a large number of ions that act as the actual current
carriers within the electrolytic solution. Therefore, the trans-
fer of Cu2" to the cathode surface by electrical migration is
eliminated. In the presence of a supporting electrolyte such
as H2SO4, Cu" ions are transferred to the cathode surface by
other mechanisms such as diffusion and convection.
When a small potential difference (V) is applied across the
electrodes, the ions move within the solution toward the
oppositely charged electrodes and accumulate near the re-
spective electrodes (see Figure 1 for the apparatus). An
ammeter placed in the circuit detects a small amount of
current (I) known as the residual current. As the applied
voltage is increased further, a high enough value of the
cathode potential, known as the discharge potential of the
electroactive species (E), is reached. At 250C and 1.0 mol/L
concentration of electroactive species, this potential is known
as the standard electrode potential (Eo) evaluated against
standard hydrogen reference electrode (H21H'). Values of the
standard electrode potentials are tabulated in the literature as
standard electrochemical series.121 When the discharge po-
tential is reached, an electrode reaction sets in and the am-
meter records a sudden jump in current. This is due to the
increased flow of electrons in the circuit because of the
exchange of electrons between the electrodes and the
electroactive ions, i.e., the electrode reactions. For the re-
duction of Cu2+ ions, the cathodic reaction may be expressed
by the following equation (the students should be encour-
aged to comment on the anodic reaction)
Cu2++2e-Cu (2)
The equilibrium deposition potential is given by the Nernst
E=Eo + nCb (3)

The value of the equilibrium potential of the system CulCuSO4
can be determined by measuring the potential difference
between the copper electrode (CulCuSO4) and a suitable
reference electrode by means of a high impedance volt-
Due to the discharge of some Cu2+ ions, the concentration
of Cu2+ ions in the immediate vicinity of the cathode is
decreased to C. Accordingly, the interfacial solution density
decreases from Pb to pi and this density difference gives
rise to a buoyancy force, gAp, which causes upward solu-
tion flow at the electrode surface. This flow enhances the
transfer of Cu2+ from the solution bulk to the edge of the
diffusion layer.
A boundary layer (known as the Nernst diffusion bound-
ary layer and also as the effective mass transfer boundary
layer) of thickness 8 is established between the bulk solu-
tion and the electrode (see Figure 2b). The value of 8 is
determined by the magnitude of the upward flow (natural

convection) as well as solution physical properties. The
effective mass transfer boundary layer thickness (8) is de-
fined in such a way that the concentration gradient at the
electrode surface, (Cb-Ci)/6, is as shown in Figure 2b. The
concentration gradient causes the transfer of Cu2+ ions across
the diffusion layer from bulk solution to the electrode sur-
face by molecular diffusion.
As the applied cell voltage is gradually increased, the
corresponding current increases owing to the increase in the
rate of Cu2+ deposition at the cathode. This is followed by a
further decrease in the interfacial Cu2+ concentration (C,) and
an increase in the cathode potential above the equilibrium
deposition potential E (see Eq. 3). Assuming that reaction
(2) is fast, i.e., there is no activation polarization and there is
no ohmic drop in measuring the cathode potential, the differ-
ence between the actual deposition potential and the equilib-
rium deposition potential is known as concentration polar-
ization (ric) and its magnitude is given by
Ic =- RT en Ci (4)
nF Cb (4)
If the cell voltage is sufficiently increased, a state is reached
where the interfacial Cu2- concentration becomes zero and
the rate of mass transfer becomes maximum. Under this
condition, the current attains a constant value known as the
limiting current (IL). In the meantime, the cathode potential
increases to a high value where H2 gas starts to evolve
simultaneously with copper deposition according to the re-
2H++e---H2 (5)
Obviously, the value of IL will depend on the value of the
limiting driving force gradient, i.e., Cb /8. In the absence of
any mechanical agitation (assuming transfer of Cu2+ by elec-
trical migration is eliminated by H2SO4 supporting electro-
lyte), the flux of Cu2+ ions (NCu2') may be obtained from

Ncu2+ F AC = KAC = KCb (6)
SKACb (7)

which yields

K= IL(8)
nFACb (8)
where Ncu2+ is the diffusional flux of Cu2+ ions, i, is the
limiting cathodic current density (limiting cathodic current
per unit cathode area, IL/A), n is the number of electrons
involved in the electrode reaction (2 for the reduction of
Cu2+ ions according to Eq.2), F is Faraday's constant
(96,500 Coulomb/equivalent), and A is the active surface
area of the electrode.
Knowing the physical properties of the solution [viscosity
(9L) and bulk (p) and interfacial (pi) densities] the diffusion
coefficient of electroactive ions (D) and the characteristic

length dimension of the electrode (1), the dimensionless groups

Sh(= KI/ D), Gr(= g13p / 2pb), and Sc(= p / pD)
can be determined. Hence the constants a and P of Eq. (1)
can be evaluated.
There are a variety of cathode shapes to choose from, but
the easier ones to work with are vertical cylinders with ends
made inactive by coating with wax or epoxy resin. In this
case, the characteristic length 1 is the cylinder height.

A typical apparatus using a 5-cm diameter cylindrical
copper cathode is shown in Figure 1. A plexiglass container
of 14-cm diameter and 55-cm height is used as the cell. The
anode is a pure copper sheet rolled to fit in the container.
Using an anode made of pure copper ensures the constancy
of CuSO4 bulk concentration (Cb) in the cell at the initial
value owing to the fact that copper dissolves from the anode
at a rate equal to that of cathodic copper deposition during
electrolysis. The circuit consists of 12-volt d.c. power sup-
ply with internal voltage regulator and a multirange ammeter
connected in series with the cell. The cathode (cylinder) is
connected to the negative pole of the power supply, while
the anode is connected to its positive pole. Polarization
curves from which the limiting current is determined are
obtained by increasing the current stepwise through the vari-
able resistance (see Figure 1) and measuring the correspond-
ing steady-state cathode potential against a reference Cu/
CuSO4 electrode placed in the cup of a Luggin tube whose
tip is placed 0.5-1 mm from the cathode surface. The Luggin
tube is filled with the same cell solution. A high impedance
voltmeter should be used to measure the potential difference
between the cathode and the reference electrode.
The cell solution contains 1.5 mol/L H2SO4 (supporting
electrolyte) containing different concentration of CuSO4, viz.,
0.05, 0.1, 0.15, 0.2, and 0.25. The experiment can be con-
ducted at room
temperature. The TABLE 1
physical proper- Physical Properties of Copper Sulphate
ties of the solu- Solution
tion needed for in 1.5 M HSO, at 240C
data correlation
are shown in [CuSo,] Viscosity Diffusivity Density (p-pi)
Table 1.'[34' If a (mol/L) (cp) x 106(cm/s) (g/cm3) (g/cm3)
12-volt d.c. 0.01 1.197 6.28 1.09 0.0014
power supply 0.0498 1.260 5.93 1.093 0.0068
with internal 0.0688 1.242 6.04 1.092 0.0093
voltage regulator 0.0966 1.263 5.94 1.097 0.013
is not available, 0.1890 1.300 5.80 1.103 0.025
a 12-volt auto-
mobile battery and a rheostat can be used. Also, the plexiglass
container and the long electrodes can be replaced by a glass
beaker and short electrodes.

Chemical Engineering Education

1. The class may be divided into five groups.
2. A cylinder of 60-cm length should be cut from copper rods of
available diameters (10-50 mm). The active cylinder height
can be changed by isolating the upper part of the cylinder by
wrapping a Teflon tape on it. Alternatively, epoxy resin or
molten bee's wax can be used to control the active part of the
3. All solutions should be prepared by the laboratory technolo-
gist prior to the scheduled lab hour.
4. Each group should obtain the polarization data (current vs.
cathode potential) by increasing the applied current stepwise
and recording the corresponding cathode potential until the
onset of hydrogen evolution (see Figure 3 for a typical experi-
mental curve) for one cylinder height but different [CuSO4].
Each experiment will take about 20-25 minutes. The students

30o00 I

Figure 3. Typical polarization curves at different
cylinder heights.


0 10 20 30 40
Cylinder height, cm

50 60

should be advised to clean the cathode surface with a fine
emery paper before each test to remove any adhering copper
powder from previous experiments.
5. Different groups should study the effect of cathode height on
limiting current and mass transfer coefficient (see Figures 4
and 5, respectively, for typical experimental data).


1. Notice the decrease in the limiting current and the mass trans-
fer coefficient with increasing cylinder height owing to the
increase in the thickness of the hydrodynamic boundary layer
and the mass transfer boundary layer as the solution moves
along the cylinder (see Figure 2a). Determine the relation
between the mass transfer coefficient and cylinder height and
compare it with the prediction of the hydrodynamic bound-
ary-layer theory.[3"561
2. Calculate Sh, Gr, and Sc numbers using the experimental
limiting current date, the electrode height, and the physical
properties given in Table 1.

3. Determine values of a and p for Eq. (1) (see Figure 6 for
typical experimental results indicating that for this case, for
the range 1.8 x 1010 < Sc Gr < 4 x 10'3, Sh = 0.64 (Sc Gr)0258
with an average deviation of 7.2%).
4. Compare the above-mentioned values of the constants
a and P with those of the corresponding mass and heat trans-
fer equations reported in the literature.'"51
5. Calculate the mass transfer coefficient using Eq. (1) and com-
pare this predicted value with the experimental value deter-
mined from Eq. (8).
6. Discuss what happens at a current value slightly larger than
the limiting current for copper deposition.
7. Check the electrodes for surface smoothness after the experi-
ment to see whether the anode is smoother than the cathode,
and give a possible explanation.
8. Record your observations on the structure of the deposited






S 0.0001



CuS04 Conc., M
0 0.0498
A 0.0688
E 0.0966

0 20 30 40 50
10 20 30 40 50

cylinder height, cm

Figure 5. Effect of cylinder height on the mass
transfer coefficient.

Fall 2000



1200 1400

0 200 400 600 800 1000
cathode potential, my

CuS04 conc., M
0 0.0498
A 0.0688
[ D 0.0966
0 0.189


Figure 4. Effect of cylinder height on limiting
current desities.

1.E+13 11E+14

Figure 6. Overall mass-transfer correlation for the range
1.8 x 1010 < Sc Gr < 4 x 1013, Sh = 0.64 (Sc Gr)0.258
with an average deviation of 7.2%

copper at different current densities, noticing that below the
limiting current a compact adherent copper deposit is ob-
tained, while at the limiting current copper powder starts to
deposit. The effect of current density on deposit structure has
an important industrial implication in electrochemical indus-
tries such as electrowinning of metals from their natural ores,
electrorefining of metals, electroforming, and electroplating.
Usually an operating current density below the limiting value
is used to obtain a compact adherent deposit. Operation at the
limiting current density is used in industry only when it is
required to produce metal powder. Metal powders are needed
in the metallurgical industry for fabricating objects by the
powder metallurgy technique (see Reference 6 for the mecha-
nism of metal powder formation at the limiting current).
9. Comment on the possible sources of error, e.g., surface rough-
ness due to copper deposition at limiting current density,
especially at high copper sulphate concentrations in solutions,
and the slight incline usually found in the limiting current
10. Using Faraday's law as given by Eq. (9) below, calculate the
daily rate of copper production (m) that is carried out in
industry at a current density 30-50% of the limiting valued' in
the form of compact adherent deposit:

m=elt (9)

e = electrochemical equivalent = equivalent weight (10)
11. Calculate the electrical energy consumed in the electrolytic
production of copper in kWh/kg from the formula

Total cell voltage (V)xl (
1000xamount produced in kg/h

The cell voltage at the operating current density can be
measured by connecting a voltmeter in parallel with the cell,
as shown in Figure 1.

CuSO, Cone., M
x 0.01
0 0.0498
A 0.0688
O 0.0966
* 0.189

Chemical Engineering Education



1.E+09 1.E+10 1.E+11 1.E+12



A cathode area, cm2
C concentration of copper sulphate, mol/cm3
D diffusion coefficient, cm2/s
d cylinder diameter, cm
e electrochemical equivalent, g/Coulomb
E,Eo equilibrium and standard deposition potentials, respec-
tively, V
F Faraday's constant (96500 Coulomb/equivalent)
g acceleration due to gravity, cm/s2
IL limiting current, A
iL limiting current density, A/cm2
K mass transfer coefficient, cm-s'
1 characteristic length dimension in Sherwood and Grashof
numbers, cm (cylinder height in the present case)
m mass production, g
N diffusional flux of electroactive species, mol/cm2s
n number of electrons involved in the reaction
R gas constant, Joule/deg. mole
Rj Ohmic resistance, ohms
T temperature, K
t time, s
V cell voltage, V
Dimensionless Groups
Gr Grashof number (gl3Ap / v2b)
Sc Schmidt number (g/pD)
Sh Sherwood number (KI/D)
Greek Symbols
a,p constants
v kinematic viscosity of the bulk solution, p/p, cm2/s
p density of the bulk solution, g/cm3
Ap density difference between the bulk and the interfacial
solution, g/cm3
5 thickness of mass transfer boundary layer, cm
Tic concentration polarization, V
b bulk
i interfacial
c cathodic

1. Selman, J.R., and C.W. Tobias, "Mass Transfer Measure-
ment by the Limiting Current Technique," Advances in
Chem. Eng., 10, 211 (1978)
2. Weast, R.C., and M.J. Astle, Handbook of Chemistry and
Physics, 61st ed., Boca Raton FL, D-155 (1980-81)
3. Wilke, C.R., M. Eisenberg, and C.W. Tobias, "Correlation of
the Limiting Currents Under Free Convection Conditions,"
J. Electrochem. Soc., 100, 513 (1953)
4. Eisenberg, M., C.W. Tobias, and C.R. Wilke, "Selected Physi-
cal Properties of Ternary Electrolytes Employed in Ionic
Mass Transfer Studies," J. Electrochem. Soc., 103, 413 (1956)
5. Thomas, L.C., Heat Transfer, Prentice Hall, Englewood Cliffs,
NJ (1992)
6. Ibl, N., Advances in Electrochemistry and Electrochemical
Eng., 2, 49 (1962)
7. Ettel, V.A., and V.B. Tilak, Comprehensive Treatise of Elec-
trochemistry, 2, 333; eds., J.O. Bockris, B.E. Conway, E.
Yeager, and R.E. White, Plenum Press (1981) O

Teaching Cellular Automation Concepts
Continued from page 309.

teams or were generally intended for the entire group to
read, suggesting that the WebBoard actually promoted col-
laboration between teams as well as within them. Individual
assignments also indicated student collaboration. Individu-
ally written computer codes frequently had similar core al-
gorithms, suggesting those team members worked together.
Analysis of individually written assignments, however, ap-
peared more independent and were frequently considerably
different. Some teams also showed more evidence of col-
laboration that others and were clearly working together
better than others. Such teams had an observably more com-
patible mix of students.
Peer review of written reports was encouraged but not
formally enforced. Revision of team reports, however, was
required, producing significant improvement in final docu-
ments. Evidence of collaboration was also seen in individual
team member reports. Collaborating teams had better inte-
gration between individual reports, particularly noted by
PhD papers and proposals that clearly brought together the
information reported in the individual papers for that team.
Of the twelve students in the course, three have gone on to
pursue research with the principal author in areas related to
the course subject, thereby offering an indirect measure of
success of the course.
Finally, students wrote many constructive remarks as part
of the assessment process. Some comments stand out, how-
ever, as examples that we like to think illustrate the mood
and tenor of the activity. This WebBoard entry was made by
one of the PhD students at the end of the semester:
I thought I would utilize the...conference room one more time.... I
really enjoyed the...interdisciplinary class. The class was both
challenging and thought provoking....You think you have a good
handle on a material and then you get blindsided with a whole
new aspect. I have a deeper appreciation for the other disci-

Experimental courses such as this one should be attempted
and studied in a careful and scientific manner. Further work
should emphasize controlled evaluation to determine the
level of learning and the interaction between students. Other
alternative teaching and learning environments should be
tested in an effort to optimize learning for all students.

1. von Neumann, J., "The General and Logical Theory of Automata,"
in J. von Neumann Collected Works, ed. A.H. Taub, Vol. 5, p. 288;
Theory of Self-Reproducing Automata, ed A.W. Burks, Univ. of
Illinois Press, (1966); Essays on Cellular Automata, ed. A.W. Burks,
Univ. of Illinois Press (1970)
2. Chaudhuri, P.P., D.R. Chowdhury, S. Nandi, and S. Chattopadhyay,
Additive Cellular Automata, Theory and Applications, Vol. 1, IEEE
Computer Society Press, Los Alamitos, CA (1997)

Fall 2000

3. Brieger, L., and E. Bonomi, "A Stochastic Cellular Automaton Simu-
lation of the Non-Linear Diffusion Equation," Physica D., 47, 159
4. Bentz, D.P., "Three-Dimensional Computer Simulation of Portland
Cement Hydration and Microstructure Development," J. Am. Ceram.
Soc., 80(1), 3 (1997)
5. Bentz, D.P., P.V. Coveney, E.J. Garboczi, M.F. Kleyn, and P.E.
Stutzman, "Cellular Automaton Simulations of Cement Hydration
and Microstructure Development," Modeling Simul. Mater. Sci. Eng.,
6. Bentz, D.P., and E.J. Garboczi, "Percolation of Phases in a Three-
Dimensional Cement Paste Microstructural Model," Cem. and Conc.
Res., 21, 325 (1991)
7. Coverdale, R.T., E.J. Garboczi, and H.M. Jennings, Comp. Mater.
Sci., 3, 465 (1995)
8. Hicks, M.D., and J.S. Katz, "Where is Science Going?" Sci., Tech., &
Human Values, 21(4), 397 (1996)
9. Gulden, W., "Using Physics Principles in the Teaching of Chemistry,"
J. Chem. Ed., 73, 771 (1996)
10. Mason, T.C., "Integrated Curricula: Potential and Problems," J.
Teachr. Ed., 47(4), 263 (1996)
11. Dahir, M., "Educating Engineers for the Real World: Survey of Engi-
neers' Education Experience," Tech. Rev., 96(6), 14 (1993)
12. Marchman, J.F., "A Multi-National, Multi-Disciplinary, Vertical In-
tegrated Team Experience in Aircraft Design," AIAA Paper 98-0822,
Aerospace Sciences Meeting, Reno, NV (1998)
13. Johnson, D.W., R.T. Johnson, and K.A. Smith, Active Learning: Coop-
eration in the College Classroom, Interaction Book, Edima, MN (1991)
14. Collaborative Learning: Underlying Processes and Effective Tech-
niques, K. Bosworth, and S.J. Hamilton, eds., Jossey-Bass, San Fran-
cisco, CA (1994)
15. Bruffee, K.A., Collaborative Learning: Higher Education, Interdepen-
dence, and the Authority of Knowledge, The Johns Hopkins Univer-
sity Press, Baltimore and London (1993)
16. Millis, B.J., and P.G. Cottell, Jr., Cooperative Learning for Higher
Education Faculty, Oryx Press (1998)
17. Rubin, L., and C. Herbert, "Model for Active Learning: Collaborative
Peer Teaching," College Teaching, 46(1), 26 (1998)
18. Wankat, P.C., and F.S. Oreovicz, Teaching Engineering, McGraw-
Hill, New York, NY (1993)
19. Angelo, T.A., and K.P. Cross, Classroom Assessment Techniques: A
Handbook for College Teachers, 2nd ed., Jossey-Bass, San Francisco,
CA (1993)
20. Biernacki, J.J., "Interdisciplinary Studies in Multi-Scale Simulation
of Concrete Materials." Resources for faculty ~jbiernacki/Multiscale Simulation_Course_Info.html> Tennessee
Technological University
21. Engineering Criteria 2000, 3rd ed., Engineering Accreditation Com-
mission of the Accreditation Board for Engineering and Technology
22. Emanual, J.T., and K. Worthington, "Team-Oriented Capstone De-
sign Course Management: A New Approach to Team Formulation
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New York, NY, 229 (1989)
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Eng. Ed., 38 (1982)
24. Smith, K.A., "Cooperative Learning Groups," in Strategies for Active
Teaching and Learning in University Classrooms, S.F. Schomberg,
ed., Continuing Education and Extension, University of Minnesota,
Minneapolis, MN (1986)
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26. Garboczi, E.J, D.P. Bentz, and K. Snyder, "Electronic Monograph on
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Cement Hydration and Microstructure Development Modeling Pack-
age," National Institute of Standards and Technology, NISTIR 5977
(1997) -





Louisiana Tech University Ruston, LA 71272

he world is undergoing sweeping changes in science
and engineering through a fast-paced revolution in
miniaturization technologies. Following methods and
processes from the microelectronics industry, engineers and
scientists are contributing to the rapid development of
micro-electro-mechanical devices (MEMS) and related ad-
aptations of chemically- and biologically-based
microsystems-changing both our depth of understanding
and our modes of interaction with the world around us. A
broad range of devices is being created-from sensors for
detecting biological and chemical agents to micro-scale
pumps, valves, separators, and reactors.
This exciting growth offers tremendous potential to the
chemical process industries through chemical process min-
iaturization (CPM). CPM technologies will find application
in a variety of ways, including environmental sensing and
control, improved operation of chemical processes (e.g.,
rates and yields), stronger economic performance through
reduced capital costs, and increased safety for processing

Frank J. Jones is Assistant Professor of Chemi-
cal Engineering at Louisiana Tech and has
taught undergraduate and graduate transport
phenomena, transport laboratories, and air pol-
lution control. He received his BS from the Uni-
versity of Pennsylvania and his MS and PhD
degrees from Drexel University. His present .
research emphases are in fluid mechanics and
chemical process miniaturization.

Bill B. Elmore is Associate Profesor and Pro-
gram Chair of Chemical Engineering at Louisi-
ana Tech and has taught undergraduate and
graduate chemical engineering reactor design
and biochemical engineering. He received his
BS, MS, and PhD from the University of Arkan-
sas. His present research emphases are in
biochemical engineering and chemical process

hazardous materials.
The unique principles governing CPM and the strong in-
terdisciplinary nature of such an endeavor motivates us to
engage our students in the discovery of fundamental chemi-
cal engineering principles linked to CPM applications. Our
goal in the chemical engineering program at Louisiana Tech
University is to integrate rapid advances from both the lit-
erature and our research work into the chemical engineering
undergraduate and graduate curriculum to initiate students'
interest and participation in this innovative area of chemical
processing. We are developing curricular modules in the
areas of micro-scale fluid behavior, reaction kinetics, physi-
cal chemistry, and biochemistry applications, highlighting
the special physical and chemical features of CPM.

The reactor forms the heart of a tremendous variety of
industrial processes. Likewise, the chemical reactor will
constitute the core process in a "micro chemical plant."
Micro-scale systems are characterized by processing units
of sub-millimeter dimensions and extremely large surface
area-to-volume (S/) ratios. Heat transfer and temperature
control play an important role in chemical reaction pro-
cesses. Because of the inherently large surface area-to-vol-
ume ratios, microreactor systems offer the advantage of
optimizing heat removal and maintaining a constant tem-
perature for equilibrium considerations. Through relatively
small amounts of injected chemicals per unit of processing
equipment and accompanying high rates of heat transfer,
these systems offer significant improvements in process
A further benefit CPM provides is a reduction in safety
hazards"' and environmental pollution by eliminating the
need for transportation and storage of toxic or explosive
chemicals.[2] CPM can provide as-needed, on-line produc-

Copyright ChE Division of ASEE 2000

Chemical Engineering Education

By involving a number of undergraduates in our research activities through introduction of this
material into the curriculum, we hope to help our students develop an interest in
CPM and to become conversant in the language of micro-scale technologies.

tion with a modular system. Additionally, a much higher
throughput per unit volume can be accomplished when com-
pared to a conventional packed-bed reactor. At the micro-
scale, fluids are generally transported in laminar flow. Mass
transfer therefore occurs primarily through diffusion (e.g.,
little or no turbulent mixing). While this is a serious limita-
tion in traditional systems, microstructures capitalize on this
"diffusion-only" transport phenomenon by bringing the mov-
ing fluid into close proximity with the reactive surfaces.
Shrinking the system geometry can result in tremendous
increases in the rates of chemical reaction, heat, and mass
transfer. Indeed, it has been observed that "diffusion is 100
times faster when a system is 10-fold smaller."131 Scale-up is
accomplished simply by creating an array of microreactors
(i.e., linear scale-up). This is far quicker and more cost-
efficient than the traditional approach of proceeding through
bench scale and pilot plant to full production. The realization
of these advantages will further enhance the process eco-
nomics, particularly for processes relying on very expensive
reactants. Beyond chemical catalysis, the miniaturization of
mixing, separations, and other unit operations offers similar
process improvements to those described.
Process parameters, which cannot be further optimized in
macro-scale reactors, can be improved in microreactors. The
large S/V ratios promote rapid response of the chemical
process to control modulations. Microfabrication processes
enable control over the diffusional path length of reactants
through the construction of precisely dimensioned
microchannels. Secondary reactions may be reduced or elimi-
nated, resulting in products of high purity.
As research tools, the advantages of miniaturized chemi-
cal processing units can be used to study poorly understood
processes. On a production level, these advantages may also
reduce the need for costly separation processes-often the
most expensive part of traditional chemical processing at the
With these advantages of scaling to the micrometer (or
even nanometer) level, large exchange rates at the catalyti-
cally active surfaces are realized. For fluid reactions cata-
lyzed at solid surfaces, a high degree of conversion is ex-
pected. There should be similar advantages for mass fluxes
through membranes in reactors and separators. As a result of
the precise, regular features of micro-reactor channels, the
equilibration of space, velocity, and temperature across and
along the reactor channels is expected. This should increase

Figure 1. An SEM photograph of a microreactor section.
Channels are chemically etched in silicon. Cross-sectional
dimensions are approximately 100 pm x 100 Mm.

selectivity compared to conventional packed-bed reactors
that have a well-known non-isothermal temperature profile.
Conventional packed-bed reactors often experience channel-
ing, whereby fluids flow through paths of least resistance
using only a fraction of the reactor bed. This problem in
operating efficiency can virtually be eliminated in channel-
based microreactors. Microreactors are essentially a "pores-
only" model of a packed bed-thereby greatly reducing or
eliminating diffusion resistances. Using micro-channel de-
vices, heterogeneous catalysis and reaction kinetics can be
isolated and studied in ways not otherwise possible.[451
While numerous advantages are potentially available, cer-
tainly not all chemical processes are suitable for adaptation
to chemical process miniaturization. Obviously, the tremen-
dous flow rates of bulk/commodity chemicals and petroleum
products are outside the range of consideration in the near
term. Further obstacles to employing CPM are seen with
processes requiring solids/liquids handling. The suitability
for its use with high-cost reactants, high-value products or
with substances of a hazardous nature justifies both the
ongoing research in CPM and the dissemination of this knowl-
edge to students of chemical engineering.

An example of microfabrication suitable for introducing
CPM at the undergraduate level is the manufacture of a
micro-scale reactor. Figure 1 depicts a set of parallel
microchannels approximately 100 micro-meters in depth.

Fall 2000


Jr ~ =~ai~~

- .- ~- ~.0 <*5~.

t; M~~* eA--R~J~;ZI -~ I'i-- .- -

These channels were achieved by chemical etching ("wet-
etching")-a process adapted from the microelectronics in-
dustry. A catalyst, such as platinum, is then applied by
"sputtering" onto the channel surfaces. A simplified sche-
matic of this process is presented in Figure 2. The wet-
etching procedure shown depicts one of a growing number
of manufacturing techniques available for constructing chemi-
cal processing equipment at the micro-scale. Photolithogra-
phy, micromachining, hot-embossing, ion-beam etching, and
X-ray lithography are only a few of the many microfabrication
techniques used. Beyond silicon wafer processing, micro-
scale structures are now being fabricated in a variety of
polymeric materials.5'1 The relative "newness" and unfa-
miliarity of these techniques to chemical engineering stu-
dents warrants an overview in an introductory CPM course.
Micro-reactor configurations other than the parallel array
of microchannels are being developed. One example is the
integration of membrane technologies with microreactors.171
This combination can provide a means of product purifica-
tion and the reduction of product inhibition simultaneously
with reaction. The use of polydimethylsiloxane (PDMS or
silicon rubber) with biological enzymes is being studied for
use as a biologically-based microreactor.[61

An overview of the development of microfabrication tech-
nologies is necessary as a basis for allowing students to
place CPM within the context of recent advances in the field.
An introductory course was offered at Louisiana Tech for
the first time in the fall quarter of 2000 (see Table 1). For
those students interested in pursuing more detailed training,
additional courses are offered that further address

microfabrication principles and
Table 1). A course focused on
chemical process miniaturiza-
tion stands uniquely apart and
can augment the existing cur-
ricular emphases in surface sci-
ence and microelectronics pro-
cessing technology currently
provided by several chemical
engineering programs around
the country.
We believe it is also neces-
sary to integrate into our exist-
ing chemical engineering
courses the special elements of
flow, heat transfer, and reaction
kinetics that arise in micro-scale
systems. Table 2 outlines the
courses currently offered in


techniques (also shown in

(1) Single Crystal Silicon <100> with
1im SiOs layer

(2) Spm Coating Photoresist Ahotoreeist

(3) Microreactor mask

(4) Exposure to UV light
ma. k

Louisiana Tech's chemical engineering program that are
being examined for suitable introduction of CPM topics. For
example, technical electives such as air pollution control and
biochemical engineering provide an excellent avenue for pre-
senting novel micro-scale applications, including environmen-
tal sensors, catalytic convertors,191 and bioreactor systems.

A brief overview illustrates some of the unique features of
micro-scale processes. These topics will be introduced, where
appropriate, to the existing chemical engineering courses.
Fluid flow Fluid flow in typical tubes and channels be-
haves as a continuum and follows well-known continuum
mechanics. Continuum flow is characterized by a linear
pressure drop along the channel length. As the lateral dimen-
sion of the channel decreases to tens of microns, the fluid
continuum begins to break down. Continuum mechanics
combined with a slip function at the walls is used to describe
flow in this regime. Arkilic, et al.,1"l have measured a non-
linear pressure drop in this so-called slip-flow regime.
Further reduction in channel dimension causes the flow
continuum to break down completely. The flow in this in-
stance has a statistical description rather than a continuum
and is often called Knudsen flow. CPM requires a focus
on reactive systems experiencing fluidic flow across these
three regimes-continuum, slip-flow, and Knudsen or
free molecular flow.
Chemical reaction For reactions occurring in
microreactors, fluid molecules move along the micro-chan-
nel, reacting when they come into contact with the catalyst-
coated wall. Kinetic theory is used to describe these wall
collisions and subsequent reaction rates.
Heat transfer Reactions occurring in the channels are

either exothermic or endother-
mic. In conventional packed-
bed reactors, this causes the
temperature to vary within the
reactor. This change in tem-
perature may adversely affect
the formation of desired prod-
ucts or unwanted byproducts.
Analogous to micro-heat ex-
changers, micro-reactors have
an enormous heat transfer area
per unit reactor volume. This
characteristic gives the micro-
reactor an equilibrium advan-
tage due to the relative ease of
accomplishing the necessary
heat transfer to maintain a con-
stant temperature throughout

Chemical Engineering Education

(5) Develop

(6) Buffered HF etching of SiOa

(7) Strip Photoreslst

(8) Anisotropic Etching in KO1

(9) Deposit Pt Catalyst

Figure 2. Steps for microreactor fabrication.


the reactor. Constructed of the proper materials and control
systems, micro-reactors should be able to operate isother-
mally. With regard to heat transfer, studies with micro-heat
exchangers have exhibited excellent performance.1t11 Heat
transfer rates are enhanced at the small scale.

As with any emerging field of engineering or science, the
"history" or "roots" of its existence is vital for laying a
proper foundation upon which future practitioners can
build. In the absence of a text at present, we use recent
literature citations along with our own experience to "tell
the story" of CPM.
The concept of free molecular flow and its deviation from
a continuum model was examined by Knudsen early this
century. Recently, Norberg, et al.,'81 studied fluid flow and
chemical reaction in microchannels. Observed molecule/wall
interactions were more complex than simple diffuse scatter-
ing. In their reaction studies, platinum was sputtered onto a
silicon surface, serving to catalyze the reaction of oxygen
and hydrogen to water.
Lerou, et al.,"[2] studied the technical feasibility of
microfabricated unit operations such as flow metering, mix-

Courses in Microstructures and Microfabrication
Techniques at Louisiana Tech

] Chemical Microsystems (ChE)
U Micromechanical Systems I (ME)
U Micromechanical Systems II (ME)
L Fundamentals of Micro-Scale Heat Transfer (ME)
E Micro-System Measurements (ME)
] Lithography Processes (ME)
U Engineering Photonics (ME)
U Microsystems Metrology (ME)
E Micromechanical Machining Processes (ME)
U Microfabrication Principles (EE)
] Microfabrication Applications and Computer-Aided Design (EE)
I Advanced Microfabrication Principles with CAD (EE)

Existing Courses Under Consideration
for Integrating Chemical Process Miniaturization
Principles and Technologies

E CMEN 304 Undergraduate Transport Phenomena
CMEN 402 Chemical Reaction Kinetics and Reactor Design
CMEN 443 Air Pollution Control
E CMEN 451 Biochemical Engineering
CMEN 504 Graduate Reaction Kinetics and Reactor Design
E CMEN 514 Graduate Transport Phenomena

ing, and heat exchange within a hazardous chemical process.
The point of their investigation was to demonstrate the safety
advantages of dealing with dangerous chemicals (such as
phosgene, methyl isocyanate, cyclohexyl isocyanate) by
microprocessing. In a continuation of the same study,
Srinivasan, et al.,11'31 conducted oxidation reactions in a
reactor with a channel depth of 550 microns. They con-
cluded that these potentially explosive reactions can be con-
ducted in microreactors with a higher degree of control and
safety than with conventional reactors.
Wegeng, et al.,1Il are investigating combustion and
partial oxidation of hydrocarbons in microchannel reac-
tors. They are attempting to achieve greater product se-
lectivity and higher yield through precise temperature
control and residence time.
Weismeier and Honicke[141 are working with
microchannels etched into metal blocks. In one instance,
100 micrometer channels were machined into copper.
The copper was then oxidized to cuprous oxide (Cu2O)
for catalyzing oxidation of alkenes.
The potential of microreactor systems to serve analytical
needs is being investigated by Jacobsen, et al. "51 In their
work, various unit operations (e.g., mixing, reaction, and
separation) are performed on an etched-glass plate. This "lab
on a chip" offers performance equivalent to full-scale ana-
lytical devices at a fraction of the production cost and with the
requirement of only a fraction of traditional sample volumes.
Schuth[l6] suggests that membrane reactors should be par-
ticularly suited to the micro-scale. A membrane reactor sepa-
rates a product molecule from the reaction stream, thereby
"beating" the equilibrium limitations and greatly increasing
conversion. Shindo, et al.,1171 constructed a 6-millimeter
packed-bed reactor that dehydrogenated cyclohexane to ben-
zene. The hydrogen product was removed through a palla-
dium-silver membrane wall. Conversion was increased from
18.9% (at equilibrium) to greater than 99%.
At Louisiana Tech, modeling and experimental
microreactor studies are underway to investigate gas-solid
catalyzed and liquid-phase enzyme reactions in
microchannels.1"8221 A variety of operating conditions and
reactor configurations are being examined to experimentally
validate system modeling and simulation of such systems.
By involving a number of undergraduates in our research
activities through introduction of this material into the cur-
riculum, we hope to help our students develop an interest in
CPM and to become conversant in the language of micro-
scale technologies. Using our work and the growing body of
scientific and engineering knowledge in this area, we can
help them envision the role of the micro-scale in the future
of chemical engineering.
Continued on page 325.

Fall 2000



RONALD W. MISSEN University of Toronto Toronto, Ontario, Canada M5S 3E5
WILLIAM R. SMITH University of Guelph Guelph, Ontario, Canada NIG 2W1

or chemically reacting systems, several measures are
used for reaction "efficiency" as it relates to amount
of reaction and/or distribution of reactants and prod-
ucts. These include terms such as "yield" and "selectivity"
for products and "fractional conversion" for reactants. Such
concepts are important in the economics of chemical pro-
cesses, and it is equally important (from a pedagogical point
of view) to have a clear interpretation of their meaning. In
the literature, however, a great variety of both terminology
and definitions is used. The situation was well illustrated
years ago by comments by Yu,"m Riesser,1[2 Frye,131 and
Vogue.[41 The possibility of confusion was apparently not
resolved then, and evidently still persists, as perusal of the
literature shows.
The purpose of this note is to provide operational defini-
tions that have the following characteristics for a reacting
system, whether simple or complex:
U Each measure is normalized to have values ranging
between 0 and 1
U For products relative to a reactant with a common
element (or radical) contained in no other reactant*
yields are defined and normalized to sum to the
fractional conversion of the reference reactant, and
selectivities are defined and normalized to sum to

To define the various measures, we describe two equiva-
lent approaches:
Stoichiometric Approach which uses stoichiomet-
ric coefficients obtained from an appropriate set of
chemical equations representing the reacting
system (the treatment given here is an extension of
that given by Missen, et al.'51)
Nonstoichiometric Approach which uses element-

* This situation formally covers what is usually envisaged;
situations involving an element (or radical) common to more
than one reactant are outside our scope.

conservation equations directly without chemical
The terms "stoichiometric" and "nonstoichiometric" are used
in the same sense as in equilibrium algorithms (see, e.g.,
Smith and Missen'61).
We focus on overall measures rather than corresponding
point or instantaneous measures. Definitions of the former
stem only from considerations of conservation of mass and
have no a priori connections with kinetics (rates) or thermo-
dynamics (equilibrium), although they can be used in any
application. The definitions are given for both closed and
steady-state open/flow systems. For the former, "overall"
refers to two states, initial and final, differing in time, and for
the latter, it refers to inlet and exit streams of the control
volume, wherever it is located.
We begin with the nonstoichiometric approach, since it is
a precursor to the other. For this, we first give the element-
conservation equations, followed by the definitions, and then
an illustrative example. For the stoichiometric approach, we

Ronald W. Missen is Professor Emeritus
(Chemical Engineering) at the University of
Toronto. He received his BSc and MSc de-
grees in chemical engineering from Queen's
University and his PhD degree in physical chem-
istry from the University of Cambridge. He is
the coauthor of Chemical Reaction Equilibrium
Analysis and Introduction to Chemical Reac-
tion Engineering and Kinetics.

William R. Smith is a Professor of Engineer-
ing and of Mathematics and Statistics at the
University of Guelph. He received his BASc,
and MASc degrees in chemical engineering
from the University of Toronto, and his MSc
and PhD degrees in applied mathematics from
the University of Waterloo. He is the coauthor
of Chemical Reaction Equilibrium Analysis. His
research is in classical and statistical thermo-

Copyright ChE Division of ASEE 2000

Chemical Engineering Education


first outline the generation of chemical equations in a conve-
nient canonical form, followed by the definitions and a rep-
etition of the previous example.

For a closed reacting system, the element-conservation
equations are

bk = akin(0) = akini;
i=l i=l

k=1,2,..., M

Yield of a Product with Respect to a Particular Reactant
The yield of a product species p with respect to a reactant
species r is the ratio of the amount of p formed to the theoreti-
cal amount that would be formed if all ofr were reacted to form
p; that is, the moles of r reacted to form p per mole of r initially.
More specifically, we define the yield Yp/rk to be the ratio of
the amount of element k reacted to form product p to the
amount of element k in reactant r initially, where k is an
element (or a radical) common to p and r. We assume there is
only one reactant with the common element k. Thus

where bk is the (constant) number of moles of element k, N is
the number of system species, ak, is the subscript to element
k in the molecular formula of species i, nil0 is the initial
number of moles of species i, n, is the (final) number of
moles of i at any subsequent time, and M is the number of
elements in the N species.
For an open/flow reacting system at steady state, the cor-
responding equations are
bk = akiiln = akiex (2)
i=1 i=1
where nin is the molar flow rate of species i at the inlet of
the control volume (system), and filx is similarly the exit
flow rate (we assume only one inlet and one exit stream for
The subscripts aki form the (M x N) formula matrix A of
the system

A =(aki) (3)
rank(A) = C < M (4)

where C is the number of linearly independent element-
conservation equations, Eq. (1) or (2).

Fractional Conversion
Fractional conversion (f) of a reactant is a measure of the
amount of the reactant consumed. For any reactant r, f, is
defined as the ratio of the moles reacted to the initial moles:

n(0) n
fr r r
r (0)
imin -_ ex
fr r rin

For either definition,

f, n0) > 0 (closed system)

fr' f1in > 0 (flow system)

0 f, <1

Yp/r,k =akr Ln-0)
akr no

akp P P _i~
Yp/r,k -akr ( jil
= -

n(o) > 0 (closed system) (8)

rin > 0 (flow system) (9)

From the definition,

0 < Yp/r.k < 1


IYp/rk fr

(all k)

Selectivity of a Product
with Respect to a Particular Reactant
The selectivity (or fractional yield) of a product species p
with respect to a particular reactant species r is a measure of
the amount of r reacted to form p relative to the total amount
of r reacted; that is, the moles of r reacted to form p per mole
of r reacted. More specifically, we define the selectivity
Sp/rk to be the ratio of the amount of element k reacted to
form product p to the total amount of element k reacted from
r, where k is an element (or a radical) common to p and r.
Again, we assume there is only one reactant with the com-
mon element k. Thus

a (n -n(o)'

Sp/r,k k= ar in i,

n(0) > nr (closed system) (12)

ri" > ex (flow system) (13)

From the definition
0< Sp/rk 1

Sp/r,k = 1 (all k)

'Alternative definitions of selectivity involve the ratio of the amount
formed of a product of interest to the amount formed of one, or more
than one, other product. Such a quantity has a range of values of 0 to o,
(7) and there is a possibility of ambiguity (Schmidt'7).

Fall 2000

A R 2L

From Eqs. (5), (8), and (12), or from (6), (9), and (13),

Yp/r,k = frSp/r,k (16)
Example 1
Consider the partial oxidation of methane to obtain "syn-
thesis gas" (CO + H2) in a steady-state flow reactor; CO2 and
H20 are also formed. For a feed gas containing 0.522 mol
02/mol CH4, suppose 02 is completely reacted, 0.0524 mol
CH4 remain per mole of CH4 in the feed, and 1.820 mol H2
are produced per mole of CH4 in the feed. Calculate at the
(a) fCH4
(b) Yco2/CH4,c and Yco/CH4,C

(c) SCO2/CH4,C and SCO/CH4,C
(d) YH2/CH4,H and H20/CH4,H
(e) YH2/CH4,H and YH2o/CH4,H

Solution: Represent the system by
{(CH4, 2, CO, H2, CO2, H20), (C, H, O)}
Choose a basis amount of 1 mol CH4 in the feed. Numbering
the species and elements in the order listed, we write the
element-conservation equations, (2), for C, H, and O, re-
spectively, as

x +nex +nex =ni + ni=n +fln =1 (17)
4i1x +2fix +2ix =4n" +2fi" +2i n =4 (18)
2f ex +i~x + 2nex +fx = 2nin +fin" + 2 n +fin =2(0.522)

a n5 _n 1 0.0212-0
SCo2/CH4,C n x T 1-0.0524 = 0.0224

a133x 3f 1 0.9264-0 97
SCO/CH4,C x 0.0524 0.9776
all pn nlex 1 1-0.0524

SSp/CH4,C 1

Alternatively, the selectivities can be calculated from Eq.
(16) and the results of (a) and (b).

SYp/CH4,H = fCH4

24 ex in

a24 4 2 1.820 0.
SH2/CH4,H 4-- 4-n 2 10.0524- 0.910
a21 6 In 4 1
hex in

a a26 6- 2 0.0752 -

SH20/CH4.H = 'n' 1-0.0524 -0.0397
Sa Sp/n 4 1=1
SSp/CH4,H = CH4

a24 4 2 1.820 -09603
a21 hin -hex 4 1-0.0524

X p/CH4.H -l


From the data given
x = 0.0524, ie = 0, fie =1.820
Solving Eqs. (17) to (19) in the remaining three unknown
exit flow rates, we obtain
ix = 0.9264, ix = 0.0212, fnx = 0.0752
(a) From Eq. (6),
mn _-lex
fCH4 = = 1-0.0524= 0.9476

(b) From Eq. (9),

ex fipo
a15 5 -5 1 0.0212-0
YC02/CH4,C f -=0.0212

ai3 x fi-n I 0.9264-0 =
YCO/CH4,C =a3 fnx -" 0.9264-0 9264
all ifn 1 1


(c) From Eq. (13),

The genesis of chemical equations from element-conser-
vation equations is described by Smith and Missen,1[891 and
we only outline the essential features here. The equations are
of the form



where A, is the molecular formula of species i, vij is the
stoichiometric coefficient of species i in chemical equation j
(+ for "products" written on the right side, and for "reac-
tants" written on the left side), and R is the maximum num-
ber of linearly independent chemical equations given by

R = N rank(A)= N C (21)
Here, C, as defined by Eq. (4), is also the number of compo-
nent species, and R is also the number of noncomponent
species (these terms are discussed further below).
Equations (20) are obtainable by reduction of matrix A to
unit matrix form, A*. In A*, C is the number of unit (col-
umn) vectors, and the remaining columns represent stoichio-

Chemical Engineering Education

_7Z" -. ,
t';- -

metric vectors, one vector for each noncomponent species.
This method of generating chemical equations is called the
matrix reduction method (MRM). It may be implemented by
"hand" manipulation for systems that are not too complex,
but for general purposes, a Java applet has been provided by
Smith, et al.,"'01 for computer implementation.
The MRM generates a proper (but nonunique) set of chemi-
cal equations (20) in canonical form. In this form, each
noncomponent species appears only once, and each equation
can be regarded as representing the formation of one mole of
a noncomponent species from the set of component species.
A conventional canonical set results on elimination of frac-
tions and minus signs.
The link between nonstoichiometric and stoichiometric
approaches can be further realized from the general solution
of Eqs. (1) or (2) as a set of linear equations:

ni =-n0) +
fiix = i1 +
I i Yij= j

i = 1, 2,..., N (closed system) (22)

i= 1, 2,..., N (flow system) (23)

where the parameter 4j or j is the extent-of-reaction vari-
able introduced in 1920 by De Donder.1"

Fractional Conversion
From Eqs. (5) and (6), and Eqs. (22) and (23), in terms of
j and j,

fr= j=lv rj (closed system) (24)
n' )

__j=Vrj j
f- 0)
r rd)

(flow system)

Equations (24) and (25) also satisfy Eq. (7).

Yield of a product with respect to a particular reactant
Corresponding to Eqs. (8) and (9), we have
Closed system

r n() np Vrpp
Yp/r,k = VP n ) ( 0) ;

Flow system


Yp/r,k m-= r ; p=C+l,C+2,...,N

the chemical equation involving noncomponent product spe-
cies p in the canonical set, corresponding to that for p, Vp.
Equations (26) and (27) also satisfy Eqs. (10) and (11).

Selectivity of a product with respect to a particular
Corresponding to Eqs. (12) and (13), we have
Closed system
Vr n(0 n)-np Vrp~p
Sp/rk='P (no) -nr J --- vr ; p=C+1,C+2..., N (28)

Flow system

Sp/r,k p=C+1,C+2,...,N (29)

Equations (28) and (29) satisfy Eqs. (14) and (15). Equation
(16) also applies.
Example 2
Repeat Example 1 using the stoichiometric approach.
Solution: We are required to calculate the yield and selectiv-
ity of two sets of products with respect to the reactant CH4.
One set involves CO and CO2 with the common element C;
the other involves H2 and H20 with the common element H.
We cannot satisfy both these requirements with one canoni-
cal set of equations, since, as shown below, C=3 and there
are only 6-3=3 noncomponent species, not 4. We therefore
construct 2 canonical sets, in one of which CO and CO2 are
noncomponents, and in the other, H2 and H20 are
noncomponents. In each case, we choose a basis amount of 1
mol CH4 in the feed.
Canonical set A: Represent the system by
((CH4, 02, H2, CO, CO2, HO2), (C, O, H)}

(25) The MRM produces the following set in conventional ca-
nonical form:

in which the noncomponents are CO and CO2, as desired,
together with H20, which does not enter into the calculations
for parts (b) and (c); j are represented by ttIA,62A,3A}
for the equations in the order given. We can calculate the
(26) values of j from the information given for CH4, 02, and H2,
respectively, and the chosen basis amount:

1- 21A- 2A= 0.0524 (30)

0.522 1A 2A -3A =0

451A +2i2A -2i3A=1.82

where vp is the stoichiometric coefficient for reactant r in

Fall 2000

The solution of these three equations is

{IA =0.4632, 2A = 0.0212, 63A =0.0376}

Canonical set B: Represent the system by
{(CH4, 02, CO, H2, CO2, H20), (C, O, H)}
by interchanging H2 and CO. The resulting conventional
canonical set is
2CH4 +02 =2CO+4H2
2CO+2 =2CO2
in which the noncomponent species are H2 and H20, as
desired, and CO2, which does not enter into the calculations
in parts (d) and (e); 4j are now represented by {1B, 62B, 3B }.
The equations corresponding to Eqs. (30), (31), and (32)
are, respectively,

1- 2B1 23B = 0.0524 (33)
0.522 B 2B 33B = 0 (34)
41B =1.82 (35)

The solutions of these 3 equations is

{(1B =0.455, 62B =0.0106, 3B =0.0188}
(a) From Eq. (25) and either canonical set, A or B,

fCH4 =0.9476
(b) From Eq. (27) and canonical set A,

YCO/CH4,c A= 2(0.4632)= 0.9264
-l2A 0.0212

YCo2/CH4,C 1

as required by Eq. (11), the sum of the yields equals fCH4.
(c) From Eq. (29) and canonical set A,

S-21A 2(0.4632)
SCO 2,C I2A 0-3A 2(0.4632)+0.0212 09776

C2CH-12A 0.0224
SCO2/CH4 2(0.4632)+0.0212

As required by Eq. (15), the sum of the selectivities
equals 1. Alternatively, the selectivities can be calculated
from Eq. (16) and the results of (a) and (b).
(d) From Eq. (27) and canonical set B,

YH2 /CH4,H = -21 = 2(0.455)= 0.910

YH2/CH4,H= 2 = 2(0.0188)= 0.0376
YH20/CH4 ,H= -1

The sum of the yields equals fCH4.
(e) From Eq. (16) and the results of (a) and (d),

SH2/CH4,H =YH2/CH4,H / CH4 = 0.910 / 0.9476= 0.9603
SH20/CH4,H = YH20/CH4,H fCH4 = 0.0376 / 0.9476 = 0.0397
The sum of the selectivities equals 1.
The results of Example 2 are the same as those of Example 1.

The stoichiometric and nonstoichiometric approaches for
defining yield, selectivity, etc., are equivalent, and which
one is used is largely a matter of convenience or personal
preference. The stoichiometric approach usually lends itself
more naturally to situations in which chemical reactions are
specified explicitly, as in chemical kinetics and chemical
reaction engineering. But it requires additional effort to gen-
erate a proper set of chemical equations, most conveniently
in canonical form; furthermore, more than one canonical set
may be required for the complete treatment of a system, as
shown in Example 2. Nevertheless, the generation of chemi-
cal equations reduces the number of problem variables, { j },
to be solved for, in comparison with the number of problem
variables, r{n}, in the nonstoichiometric approach. Offset-
ting this, we do not require the generation of chemical equa-
tions in the latter.

Financial assistance has been received from the Natural
Sciences and Engineering Research Council of Canada and
the University of Toronto.

1. Yu, A.J., Chem. Eng. News, 44(2), 4 (1966)
2. Riesser, G.H., Chem. Eng. News, 44(6), 4 (1966)
3. Frye, A.H., Chem. Eng. News, 44(6), 4 (1966)
4. Voge, H.H., Chem. Eng. News, 44(8), 5 (1966)
5. Missen, R.W., C.A. Mims, and B.A. Saville, Introduction to
Chemical Reaction Engineering and Kinetics, Wiley, New
York, NY, p 91 (1999)
6. Smith, W.R., and R.W. Missen, Chemical Reaction Equilib-
rium Analysis, Wiley-Interscience, New York, NY (1982);
Krieger, Malabar, FL, p. 118 (1991)
7. Schmidt, L.D., The Engineering of Chemical Reactions, Ox-
ford University Press, New York, NY, p. 153 (1998)
8. Smith, W.R., and R.W. Missen, Chem. Eng. Ed., 13,26 (1979)
9. Reference 6, Chapter 2
10. Smith, W.R., I. Sikaneta, and R.W. Missen, Web site located
at . The site also con-
tains a tutorial on Chemical Reaction Stoichiometry (1998)
11. De Donder, Th., L'Affinitg, revised by P. Van Rysselberghe,
Gauthier-Villars, Paris, p. 2 (1936) 0

Chemical Engineering Education

Miniaturization in the Curriculum
Continued from page 319.

Science and technology is moving forward at a breath-
taking pace. Never before in history have so many changes
occurred so rapidly. Noteworthy in the public arena are the
incredible advances in information technology and in biol-
ogy-particularly the advent of the Internet and potential
advances through the human genome project. We anticipate
the influence of chemical process miniaturization to be no
less significant in the chemical process industries.

Special thanks are offered to the Department of Defense-
EpSCOR program, Louisiana State Board of Regents Sup-
port Fund, the chemical engineering program, and the Insti-
tute for Micromanufacturing (IfM) at Louisiana Tech Uni-
versity for funding our research and curriculum reform ef-
forts. Thanks to Ji Fang of the IfM for his fabrication assis-
tance and SEM photographs of etched microchannels.

1. Srinivasan, R., I.-M. Hsing, J. Ryley, M. P. Harold, K. F.
Jensen, and M. A. Schmidt, "Micromachined Chemical Re-
actors for Surface Catalyzed Reactions," Solid-State Sen-
sor and Actuator Workshop Proceedings, Hilton Head,
SC, (1996)
2. Ehrfeld, W., V. Hessel, A. Mobius, and T. Richter, "Poten-
tials and Realization of Microreactors," Microsystem Tech-
nology for Chemical and Biological Microreactors, Max Plank
Institute, Mainz, Germany, (1995)
3. Freemantle, M., "Downsizing Chemistry," C&E News, Feb.
22 (1999)
4. Somorjai, G., Plenary Lecture on Catalysis, European Fed-
eration of Catalysis Society's 2nd European Congress on
Catalysis, Maastricht, the Netherlands (1995)
5. Madou, Marc, Conference Chairperson, "Manufacturing and
Commercialization Issues for Micro & Nano Medical De-
vices," 2nd Annual BIOMEMS 2000 Conference, San Fran-
cisco, CA
6. Dickey, C.K., B.B. Elmore, and F. Jones, "Enzyme Cata-
lyzed Biochemical Production in a PDMS Microreactor," to
be presented at the SPIE symposium on Micromachining
and Microfabrication, September (2000)
7. Jones, F., A. Zheng, and A. Kuppusamy, "Dehydrogenation
of Cyclohexane to Benzene in Microreactors and Membrane
Microreactors," presented at the 2000 Spring National Meet-
ing of The American Institute of Chemical Engineers (IMRET
4 Topical Conference), March (2000)
8. Norberg, P., L.-G. Peterson, and I. Lundstrom, "Character-
ization of Gas Transport Through Micromachined Submi-
cron Channels in Silicon," Vacuum, 45, 139 (1994)
9. Joshi, A.A., "Fabrication of a Miniaturized Chemical Pro-
cess," Masters Thesis, Louisiana Tech University, May (1998)
10. Arkilic, P., K. Breuer, and M. Schmidt, "Gaseous Flow in
Microchannels," ASME Application of Microfabrication to
Fluid Proceedings, Chicago, FED 197, 57 (1994)
11. Wegeng, R., C. Call, and K. Drost, "Chemical System Minia-
turization," PNNL-SA-27317, Pacific Northwest National
Laboratory, Richland, WA (1996)
12. Lerou, J.J., M.P. Harold, J. Ryley, T. O'Brien, J. Ashmead,

Fall 2000

Positions Available
Use CEE's reasonable rates to advertise.
Minimum rate, 1/8 page, $100
Each additional column inch or portion thereof, $40.

Faculty Recruiting in Chemical Engineering
The University of Texas at Austin

The Department of Chemical Engineering invites applications for a
tenure track faculty position at the Assistant Professor level. A PhD
is required and applicants must have an outstanding record of re-
search accomplishments and a strong interest in undergraduate and
graduate teaching. The successful candidates are expected to teach
core chemical engineering undergraduate and graduate courses, de-
velop a research program, collaborate with other faculty, and be
involved in service to the university and the profession. Applications
from women and minorities are encouraged. Interested persons should
submit a detailed curriculum vitae including academic and profes-
sional experience, a list of peer-reviewed publications and other
technical papers, and the names, addresses, and telephone numbers
of three or more references to: Chairman, Department of Chemical
Engineering; The University of Texas at Austin; Austin, TX 78712-
1062. The University of Texas is an Equal Opportunity/Affirmative
Action Employer.

J. Perrotto, M. Johnson, J. Niquist, and C. Blaisdell,
Microsystem Technology for Chemical and Biological
Microreactors, Max Plank Institute, Mainz, Germany (1995)
13. Srinivasan, R., I.-M. Hsing, P.E. Berger, K.F. Jensen, S.L.
Firebaugh, M.A. Schmidt, M.A. Harold, J.J. Lerou, and J.
Ryley, "Micromachined Reactors for Catalytic Oxidation
Reactions," AICHE J., 43, 3059 (1997)
14. Weismeier and Honicke, Microsystem Technology for Chemi-
cal and Biological Microreactors, Max Plank Institute, Mainz,
Germany (1995)
15. Jacobsen, S.C., R. Hergenroder, A.W. Moore, and J.M.
Ramsey, "Precolumn Reactions with Electrophoretic Analy-
sis Integrated on a Microchip," Anal. Chem., 66,4127 (1994)
16. Schuth, F., "Crystallographically Defined Pore Systems: Re-
action Vessels with Molecular Dimensions," Microsystem
Technology for Chemical and Biological Reactors, Max Plank
Institute, Mainz, Germany (1995)
17. Shindo, Y., N. Itoh, and K. Haraya, "High Performance
Reactor Using a Membrane," AIChE Symposium Series, 85,
18. Annamalai, K., and F. Jones, "Microreactor Design and
Simulation in the Slip-Flow Regime," I&EC Special Sympo-
sium Series of the ACS, Birmingham, AL, 49 (1997)
19. Chakravarthy, S.V., and F. Jones, "Design and Simulation
of Membrane Microreactors," I&EC Special Symposium Se-
ries of the ACS, Birmingham, AL, 54 (1997)
20. Heller, E., and F. Jones, "Design of a Microreactor," Annual
Meeting of the AIChE, Chicago, November (1996)
21. Jones, F., A. Zheng, and A. Kuppusamy, "Dehydrogenation
of Cyclohexane to Benzene in Microreactors and Membrane
Microreactors," presented at the SPIE Symposium on
Micromachining and Microfabrication, Santa Clara, CA, Sep-
tember (1999)
22. Dickey, C.K., B.B. Elmore, and F. Jones "Production of
Pharmaceuticals by Immobilized Enzymes in a
Microreactor," presented at the 2000 Spring National Meet-
ing of The American Institute of Chemical Engineers (IMRET
4 Topical Conference), March (2000) O

Random Thoughts...



North Carolina State University Raleigh, NC 27695

n almost every teaching workshop we give, someone
asks if the rise of instructional technology and distance
learning signals the end of higher education as we know
it. As it happens, we believe it does, but we regard this as
good news, not bad. Consider the following two scenarios.

Scenario 1

Sharon boots up her computer, connects to her heat and
mass transfer course web site, checks out the assignment
schedule, sighs heavily, and gets to work. In the next hour
and a quarter, she
quickly reviews last week's multimedia tutorial that
presents material on convective heat transfer, asks
questions and poses problems, and provides feedback
on her responses and corrections if she misses;
watches a video of her instructor lecturing on the
same topic, advancing rapidly to his discussion of a
particular homework problem that gave her a lot of
> begins working through this week's tutorial, which
deals with a shell-and-tube heat exchanger preheating
the feed stream to a distillation column, and clicks on
a hot link in the process description that takes her to
supplementary material on heat exchangers, including
a cutaway schematic, photos of commercial exchang-
ers and tube bundle assemblies, and outlines of
exchanger operating principles and design procedures;
0 returns to the tutorial and builds the steady-state
energy balance and heat transfer equations, branching
to a linked database to retrieve needed physical
properties of the process fluids;

uses linked numerical analysis software to solve the
equations, size the exchanger, and generate plots of
shell-side and tube-side temperatures vs. axial
position along the tubes;
brings up a heat exchanger simulation and first
predicts and then explores the effects of system
parameter changes on exchanger performance;
> closes the tutorial, checks her e-mail and finds a
message from her instructor clearing up a point of
confusion she had e-mailed him about late the
previous night, sends a message to the other members
of her class project group reminding them of their
scheduled chat room conference at 7:30 that night,
and logs off.

Scenario 2

Fred goes to his 8 a.m. heat and mass transfer class,
drops his homework on the front desk, takes his seat,
yawns, and wonders if he'll be able to stay awake until

Richard M. Felder is Hoechst Celanese Professor (Emeritus) of Chemi-
cal Engineering at North Carolina State University. He received his
BChE from City College of CUNY and his PhD from Princeton. He has
presented courses on chemical engineering principles, reactor design,
process optimization, and effective teaching to various American and
foreign industries and institutions. He is coauthor of the text Elemen-
tary Principles of Chemical Processes (Wiley, 2000).
Rebecca Brent is an education consultant specializing in faculty de-
velopment for effective university teaching, classroom and computer-
based simulations in teacher education, and K- 12 staff development in
language arts and classroom management. She co-directs the SUC-
CEED Coalition faculty development program and has published ar-
ticles on a variety of topics including writing in undergraduate courses,
cooperative learning, public school reform, and effective university

Copyright ChE Division of ASEE 2000

Chemical Engineering Education

9:15. Professor Maxwell greets the class and asks the
students if they have any questions. One of them asks
about a homework problem and she goes through the
solution on the board. She then draws a block diagram
of a heat exchanger and writes the energy balance and
heat transfer equations. When she finishes writing the
last equation she asks the class how they would deter-
mine the film coefficients in the expression for the
overall heat transfer coefficient. Fred vaguely recalls
something about correlations from the last lecture but
doesn't feel inclined to say anything. When no one
volunteers a response the professor reminds the class
about the correlations and writes the equation for one of
them on the board, and then completes the calculations.
She asks again if any of the students have questions, and
they don't. She then notes that different correlations
must be used for laminar flow, and she writes an
expression for one of them. While she is writing Fred
glances at his watch, sees that it is 9:13, and closes his
notebook. The instant she finishes he wakes his neighbor
and heads for the door with the rest of the class.

These scenarios raise a question currently being pondered
throughout the academic world. If Sharon and Fred are
roughly equivalent in intelligence and knowledge of the
course prerequisites, which of them will learn more-the
one taught in the live classroom or the one taught with
technology? There's no way to know for sure, of course-
how much a student learns in a course depends on many
things-but technology is the way to bet in this example.
The rich mixture of visual and verbal information, self-tests
of knowledge and conceptual understanding, practice in prob-
lem-solving methods, and immediate individual feedback
provided by the technology in Scenario 1 are far more likely
to promote deep learning than the passive environment of
the traditional lecture class .and the fact that Sharon lives
750 miles away from her instructor's campus and has never
seen him in person doesn't change the likelihood that she
will learn more and at a deeper level than Fred.
This speculation is not baseless: studies comparing tech-
nology-based and traditional course offerings are beginning
to appear with regularity, and technology is looking better
all the time." Universities that specialize in distance educa-
tion are learning how to use multimedia courseware and the
Internet effectively and the quality of their offerings is gain-
ing increasing recognition.[2] When students in the near
future have a choice between (a) attending passive lectures
at fixed locations and times in a campus-based curriculum
and (b) completing interactive multimedia tutorials at any

convenient place and time in a distance-based curriculum,
guess which alternative more of them will begin to choose.
This is not to say that technology is a panacea. Passive
instructional technology-e.g., simply pointing a video cam-
era at a conventional lecture or using the Web only to dis-
play text and pictures-does not promote much learning, no
matter how dynamic the lecturer or how colorful the graphic
images. Moreover, even at its best technology will never be
able to do some things that first-rate teachers do routinely,
such as advising, encouraging, motivating, and serving as
role models for students, helping them develop the commu-
nication and interpersonal skills they will need to succeed in
their careers, and getting them to teach and learn from one
another. Most successful people can think back to at least
one gifted teacher who changed their lives by doing one or
more of these things; it is unlikely that anyone will ever be
able to do the same for a software package.
Here, then, is what our crystal ball says about the future
of higher education. An increasing share of undergraduate
degrees will be earned in well-designed distance-based pro-
grams at conventional universities and institutions without
walls like the British Open University,'21 and an increasing
number of people will bypass college altogether and seek
competency-based certification in fields like information tech-
nology.'3' Some highly ranked research universities will still
teach traditionally and continue to attract undergraduates by
virtue of their prestige, serving primarily as training grounds
for graduate schools. Many of the much greater number of
less prestigious universities will try to keep doing business
as usual, but having to compete for a shrinking pool of
undergraduates will force them to either change their prac-
tices or close their doors. And a growing number of universi-
ties will systematically incorporate interactive multimedia-
based instructional software in their live classroom-based
courses, making sure that the courses are taught by profes-
sors who serve as true mentors to their students and not just
transmitters of information. These universities will continue
to thrive-and they will provide the best college education
anyone can get.

1. Kadiyala, M., and B.L. Crynes, "A Review of Literature on
Effectiveness of Use of Information Technology in Educa-
tion," J. Engr. Education, 89(2), p.177 (2000); D.R. Wallace
and P. Mutooni, "A Comparative Evaluation of World Wide
Web-Based and Classroom Teaching, J. Engr. Education,
86(3), p. 211 (1997)
2. Grose, T.K., "Distance Education the UK Way,"ASEE Prism,
pp. 26, November (1999)
3. Adelman, C., "A Parallel Universe: Certification in the In-
formation Technology Guild," Change, 32(3), p. 20 (2000)0

Fall 2000

All of the Random Thoughts columns are now available on the World Wide Web at and at




Center for Electrochemical Engineering
University of South Carolina Columbia, SC 29208

We have developed a mathematical methods course
for seniors and first-year chemical engineering
graduate students that uses the matrix exponen-
tial and Maple"1 to solve initial value problems, boundary
value problems, and partial differential equations.[2'31 We
give here a brief description of some of what we cover in our

The matrix exponential (exp[At]) arises in the solution of
a system of linear, ordinary differential equations (ODEs).
For example, the time dependent concentration of species in
a series reaction[14 (A-kB- "C) can be obtained by writ-
ing the material balance equations in matrix form,[2]
--=AY+b(t) (1)
and solving Eq. (1) by using the matrix exponential'31
Y = exp(At)Yo + f exp[-A(t t)]b()d (2)
where A has been assumed to be a constant and Y, is the
initial condition vector. Equation 2 can be thought of as an
extension of the integrating factor approach for solving a
single, first-order linear differential equation. Equation 2
allows one to solve coupled linear, first-order differential
equations symbolically as a function of time, the initial
conditions, and the parameters (k, and k2 in this case).
In the Appendix, we show how to use Maple to solve for
the concentration profiles for this series reaction. Note that
Maple is capable of finding the exponential matrix, exp[At]
(mat in the Appendix) with t as the independent variable and
k, and k2 as parameters. Alternatively, one can program an

algorithm in Maple to determine the matrix exponential.
When the coefficient matrix A is a function of time, t, the
solution can be obtained by using the matrizant15"7 and not
by the matrix exponential. Linear systems of ODEs can also
be solved using Maple's Laplace transform commands or by
using Maple's dsolve command.
Nonlinear, first-order ODEs can also be solved symboli-
cally with Maple's dsolve command. Maple will provide
either an explicit solution or an implicit solution, depending
on the degree of non-linearity of the equations. In addition,
one can use Maple's dsolve (type = series) command to
obtain a series solution in terms of the independent variable
and parameters for both linear and nonlinear initial value
problems. Also, systems of nonlinear first-order ODEs can
be solved numerically by using Maple's dsolve (type =
numeric) command. For nonlinear systems of differential
and algebraic equations (DAEs),81 Taylor's BESIRK191
can be used with Maple.

Given a set of data and the model equations, Maple can be
used to estimate parameters such as k, and k2 by nonlinear
parameter estimation. The procedure consists of writing the

Venkat R. Subramanian is a doctoral student at the University of
South Carolina. He received a BS in chemical and electrochemical
engineering from the Central Electrochemical Research Institute in
India in 1997. His research involves mathematical modeling of electro-
chemical systems-lithium ion batteries, metal hydride batteries, and
current-density distributions. His research interest also includes sym-
bolic/semi-analytic/numerical solution of boundary value problems us-
ing Maple, FEMLAB, etc., and nonlinear parameter estimation from
experimental curves.
Ralph E. White is a professor and department chair in the Chemical
Engineering Department at the University of South Carolina. He holds a
BS degree from the University of South Carolina and received his MS
and PhD degrees from the University of California at Berkeley.

Copyright ChE Division of ASEE 2000

Chemical Engineering Education

. ., -- Gradua -Adu.__-)

... a mathematical methods course for seniors and
first-year chemical engineering graduate students that
uses the matrix exponential and Maple to solve
initial value problems, boundary value
problems, and partial differential

sensitivity equationsi0'o or equivalently, the Jacobian ele-
ments,'11 and solving them simultaneously with the model
equations. The matrix exponential method (Eq. 2) can be
used easily for linear systems, and dsolve(numeric) or
BESIRK can be used for nonlinear systems. Also, Maple can
be used to find the Jacobians symbolically.

Linear, two-point boundary value problems, which consist
of a second-order differential equation subject to two bound-
ary conditions at different points, can be solved by using the
matrix exponential (Eq. 2) and Maple. One simply changes
the second-order differential equation into a system of first-
order ODEs and solves the system with an unknown condi-
tion at x=0. This unknown condition at x=0 is then deter-
mined directly by applying the outer boundary condition at
x=l to the solution, as illustrated by the solution of the heat
transfer from a rectangular fin112 in the Appendix.
The direct method we have developed has apparently been
overlooked as a method for solving two-point boundary
value problems. Perhaps the reason for this is that chemical
engineers are not familiar with the matrix exponential (as a
function of the independent variable, t) and do not use Eq. 2
to solve equations. Also, before we had software such as
Maple, evaluation of the matix exponential was difficult and
time consuming. In addition, for problems that yield a coef-
ficient matrix A that depends on the independent variable,
one must use the matrizant,5-71 which is difficult to do with-
out software such as Maple. It is important to note that this
direct method (Eq. 2) can be used instead of the method of
undetermined coefficient, variations of parameters, etc., that
are commonly used for solving second-order linear BVPs.
Maple can also be used to obtain approximate solutions in
symbolic form for linear, second-order BVPs. The process
for doing this consists of using finite difference expressions
to represent the derivatives in the governing equation and
the boundary conditions, which results in an equation of the
AX = b (3)
The solution to Eq. 3 can be found by using Maple to find

the inverse of A symbolically, so that the solution is then
X = A-lb (4)
This method has been applied to the heat transfer from a
rectangular fin example in the Appendix, where it is shown
that the solution consists of expressions for the values of the
dependent variables at the node points in terms of the param-
eters of the problem (H in this case). Alternatively, Maple's
fsolve command can be used to solve linear/nonlinear alge-
braic equations arising during discretization of linear/non-
linear ODEs. Alternatively, one can use NEWTON, devel-
oped by Taylor,191 to solve a system of nonlinear equations.
The efficiency of fsolve compared with NEWTON depends
on the problem.

Time dependent heat/mass transfer in a semi-infinite do-
main occurs frequently in chemical engineering.[14-161 The
parabolic PDEs that describe these processes are often solved
by a similarity variable transformation. The solutions ob-
tained usually involve error functions or complimentary er-
ror functions.[2'3'1561 Instead of using a similarity variable
approach, one can apply the Laplace transformation tech-
nique for the time variable and solve the resulting ODE in
the Laplace domain using Eqs. (1) and (2). The solution once
obtained in the Laplace domain can be inverted back to the
time domain. We illustrate (in the Appendix) how this can
be done by using Maple's built-in Laplace transformation
commands. We used this method to solve many of the
problems given in References 15 and 16 for various
boundary/initial conditions and source terms in the gov-
erning equation.
Linear, parabolic PDEs in a finite domain can also be
solved by this method by applying the Laplace transforma-
tion in time, solving the resulting second-order differential
equation with the boundary conditions in the Laplace do
main, using the matrix exponential approach presented above,
followed by using the Heaviside expansion theoreml1 to
invert the solution back into the time domain. Maple is
especially useful for this purpose when multiple poles are
involved in the inversion""3'78 because Maple's limit com-
mand can be used to find the residues.

Fall 2000

Parabolic PDEs in a finite domain can also be solved by
separation of variables. Maple can be used to separate the
variables and integrate the resulting ODEs in time and x
variable. Oftentimes, the eigenvalues are given by a nonlin-
ear transcendental equation. If one were using FORTRAN,
one would have to find the eigenvalues by writing a Newton-
Raphson code, or refer to tables.[115"6 Maple can be used to
find the eigenvalues and store them in an array. The solution
obtained from this method is usually in the form of an
infinite series[3'4,17'18] whose coefficients are found out by
applying the Sturm-Louivelle theorem. Maple is extremely
useful in evaluating the definite integrals involved in this
tedious process. Since the final solution is stored symboli-
cally by Maple, many case studies can be done for different
parameters and the results can be plotted easily by using
Maple. This method can be extended to treat Laplace's equa-
tion in two spatial coordiantes (x and y). This type of equa-
tion occurs in steady-state heat/mass transfer in a rectangular
plate/cylinder[15'16] and potential distributions in electrochemi-
cal cells.119'201
Linear parabolic PDEs (e.g., heat transfer in a rod) can be
solved by method of lines.[21'221 The derivatives in x are
replaced by finite differences. The resulting set of coupled
linear first-order ODEs are usually numerically integrated in
time.[21'221 We represent the resulting first-order ODEs in the
matrix form (Eq. 1) and the solution is given by Eq. 2. This
allows one to solve for the dependent variable (e.g., tem-
perature, concentration) as a function of time, as shown in
the Appendix. We call this the semi-analytical method.1231
We have found it to be an extremely useful method for
solving linear PDEs. Nonlinear PDEs can also be solved this
way, by quasi-linearizing the nonlinear term and iterating
for convergence.[241 Another important aspect is that it al-
lows us to solve Laplace's equation (two dimensions in x
and y), which involves solving simultaneously coupled lin-
ear BVPs.1181
Finally, for coupled nonlinear PDEs (parabolic, elliptic,1251
or any kind), finite differences can be used in both x and y
(or t) and solved simultaneously using Maple's fsolve com-
In summary, we have found that it is possible to solve old
problems in new ways by using the power of Maple. We
suggest that the readers consider trying Maple and contact us
for help with their problems if necessary. We are planning to
write a book based on the Maple worksheets that one of us
(VRS) has prepared for our course and this paper.

1. Waterloo Maple Inc.,
2. Rice, Richard G., and Duong D. Do, Applied Mathematics

and Modeling for Chemical Engineers, John Wiley & Sons,
Inc., New York, NY (1995)
3. Varma, Arvind, and Massimo Morbidelli, Mathematical
Methods in Chemical Engineering, Oxford University Press,
New York, NY (1997)
4. Fogler, H. Scott, Elements of Chemical Reaction Engineer-
ing, Prentice Hall, Inc., Englewood Cliffs, NJ (1999)
5. Amundson, N.R., Mathematical Methods in Chemical Engi-
neering. I: Matrices and Their Applications, Prentice Hall,
Inc., Englewood Cliffs, NJ (1966)
6. Taylor, R., and R. Krishna, Multi-Component Mass Trans-
fer, John Wiley & Sons, Inc., New York, NY (1993)
7. Subramanian, V.R., B.S. Haran, and R.E. White, Comp.
and Chem. Eng., 23(3), 287 (1999)
8. Holland, C.D., and A.I. Liapis, Computer Methods for Solv-
ing Dynamic Separation Problems, McGraw-Hill, Inc., New
York, NY (1983)
9. Schwalbe, D., H. Kooijman, and R. Taylor, Mapletech, 3(2),
10. Constantinides, A., and N. Mostoufi, Numerical Methods for
Chemical Engineers with Matlab Applications, Prentice Hall,
Englewood Cliffs, NJ (1999)
11. Bard, Y., Nonlinear Parameter Estimation, Academic Press,
New York, NY (1974)
12. Davis, M.E., Numerical Methods and Modeling for Chemi-
cal Engineers, John Wiley & Sons, New York, NY (1984)
13. Subramanian, V.R., and R.E. White, "Symbolic Solutions
for Boundary Value Problems with Maple," accepted for
publication in Computers and Chemical Engineering
14. Schiesser, W.E., and C.A. Silebi, Computational Transport
Phenomena, Cambridge University Press, New York, NY
15. Carslaw, H.S., and J.C. Jaeger, Conduction of Heat in Sol-
ids, Oxford University Press, London (1973)
16. Crank, J., Mathematics ofDiffusion, Oxford University Press,
New York, NY (1975)
17. Subramanian, V.R., and R.E. White, in Tutorials in Electro-
chemical Engineering-Mathematical Modeling, R.F.
Savinell, J.M. Fenton, A.C. West, S.L. Scanlon, and J.
Weidner, eds., PV99-14, p. 100, The Electrochemical Society
Proceedings Series, Pennington, NJ (1999)
18. Subramanian, V.R., and R.E. White, "New Separation of
Variables Method for Composite Electrodes with
Galvanostatic Boundary Conditions," submitted to J. of the
Electrochem. Soc.
19. Subramanian, V.R., and R.E. White, J. of the Electrochem.
Soc., 147(5), 1636 (2000)
20. Newman, J.S., Electrochemical Systems, Chapter 18, Prentice
Hall, Englewood Cliffs, NJ (1991)
21. Cutlip, M.B., CACHE News, 18, Fall (1998)
22. Taylor, R., CACHE News, 5, Fall (1999)
23. De Vidts, P., and R.E. White, Comp. and Chem. Eng., 16(10/
11), 1007 (1992)
24. Haran, B.S., and R.E. White, Comp. Appl. in Eng. Ed., 4(3),
25. Nguyen, T.V., and R.E. White, Comp. and Chem. Eng.,
11(5), 543 (1987)

Chemical Engineering Education



APPENDIX: Solving Differential Equations with Maple

[ Appendix
[ Intial Value Problems (Series Reactions, reference 4)
> restart:with(linalg):
[ The governing equations for the concentrations of species involved in a series reaction can be written as (reference 4)
> eql:=diff(Ca(t),t)=-kl*Ca(t);eq2:=diff(Cb(t),t)=kl*Ca(t)-k2*Cb(t);

eql :=-Ca(t)= -k Ca(t)

eq2:= Cb(t)=kl Ca(t)-k2Cb(t)
L t
[ with the initial conditions
> Ca(0):=CaO;Cb(0):=0;
Ca(O):= CaO
Cb(0):= 0
[ These two equations can be written in matrix form (see equation 1 in the text, note that in this case b is zero).
> A:=matrix(2,2,[coeff(rhs(eql), (t)coe (r (eq),C(t)),coef(rh(eq2),Ca(t)),c
,coeff(rhs(eq2),Cb(t))]);YO:=matrix(2,, [CaO,0]);
A :=[ -kk1 0
k1 -k2
[ The solution is given by equation 2 with b = 0.
> mat: exponential(A,t); sol:=evalm(mat&*YO);
e'-" 0
mat := kl(e'L" e -u ) e(42,- )
-k2 + kl
e(" ') CaO
sol := kl(e(-k) e'-") CaO
> Ca:=sol[1,1];Cb:=sol[2,1];
Ca := e-k"") CaO
kl (e(- e(-k1") CaO
Cb :=
-k2 + kl
C From a material balance
> Cc:=simplify(CaO-Ca-Cb);
CaO ( k2 kl e' "') k2 + kl e'- ")'
c := -k2 + k
E Boundary Value Problems-ODEs (Heat transfer in a Rectangular Fin, reference 12)
[ > restart:with(linalg):
[ Consider the heat transfer in a rectangular fin (see references 7,12,13)
> eq:=diff(theta(x),x$2)=HA2*theta(x);
eq :=- (x)= H2 (x)
E where H is the dimensionless heat transfer coefficient and 6 is the dimensionless temperature. The boundary conditions
> bcl:=theta(0)=; bc2:=D(theta) (1)=0;
bcl := 0(0)= 1
bc2 := D(6)(1)= 0
[ We can solve this BVP by using the matrix exponential method (equations 1,2) by first converting the second order ODE

Fall 2000 331

APPENDIX: Solving Differential Equations with Maple

L into a system of first order ODEs.
[ > y[l]=theta(x):y[2]=diff(theta(x),x):Y(x)=matrix(2,1,[y[l],y[2]]):
> A:=matrix(2,2):A[1,1]:=0:A[1,2]:=1:A[2,1]:=HA2:A[2,2]:=0:A:=evalm(A);

0 1
A:= H l
[ The initial condition vector is
> YO:=matrix(2,1,[l,y[20]]);

YO :=
SL Y20
[ The solution for the matrix differential equation is (equation 2 with b = 0).
> mat:=evalm(exponential(A,x)):ma =map(convertmat,,trig) :Y:=evalm(mat&*YO);
sinh(H x) y,,,
cosh(Hx) +

-H (cosh(H x) + sinh(H x)) -2H (cosh(H x) sinh(H x)) + cosh(H x) y,,
The unknown constant y20 can be obtained by using the boundary condition at x = 1 (equate the second row in the above
equation for Y to with x = 1).
> Y1:=evalm(subs(x=l,evalm(Y)));y[20]:=solve(Y1[2,1]=0,y[20]);

cosh(H) +
Y/ :=
H (cosh(H) + sinh(H)) 2 H (cosh(H) sinh(H)) + cosh(H) y2

H sinh(H)
[ Substitution of y2o back into the solution followed by simplification yields the desired solution.
> Y:=simplify(evalm(Y)) ;Ym:=combine(Y[1,1]);
cosh(H x) cosh(H) sinh(H x) sinh(H)
H (cosh(H) sinh(H x) cosh(H x) sinh(H))
cosh(H x H)
Ym =
[ The solution to this ODE can also be obtained easily by using Maple's dsolve command.
> Ya:=rhs(dsolve((eq,bcl,bc2),theta(x)));
sinh(H) sinh(H x)
Ya := cosh(Hx) sinh(H) sinh(Hx)
Maple solves the given ODE subject to the boundary conditions However, it does not give the solution in the desired
(more familiar) form. Fortunately, Maple's combine command can be used to obtain the desired form (see reference 12, p.
> Ya:=combine(Ya);

Ya cosh(-H + H x)
[ This solution can be plotted easily vs x for particular values of H.
> with(plots):p[ll]:=plot(subs(H=0,Ym),x=0..l,thickness=4,color=red,axes=boxed) :p[2
r > display(seq(p[i],i=1..3),labels= x,theta]);

Chemical Engineering Education

APPENDIX: Solving Differential Equations with Maple

0 0.2 0.4 x 0.6 0.8 1

SThe same problem can be solved symbolically by applying finite differences in x. For illustrations two interior node points
are used here.
S> N:=2:Eq[0]:=y[0]=l:for i from 1 to N do

> eqns:=[seq((Eq[j]),j=O..N+1)];Y:=[seq(y[i],i=O..N+1)];
[ z 2 y, +yY3 2 2.v + y, 1 y,-4y +3y ,,
eqns := Yo 1, h2 -H2 y = 0, H2 y2 = 0- 2 -

Y:= [Yn ,, Y,2,3]
[ Maple is used to generate the A matrix and b (equations 3 and 4).
[ > h:=eval(l/(N+1)):A:=genmatrix(eqns,Y,'b'):evalm(b):
> sol:=evalm(inverse(A)&*b);
ol 6+H2 54 -18+H21
sol := 1,594-3 54 + 24 --- +/--
S54 + 24 H2 + 4 5 + 24 H+ 54++ 24 +
[ which shows that linear ODEs can be solved symbolically. For more details see reference 13.
[ For a particular value of H, these 4 equations can be solved using Maple's fsolve command
> fsolve({seq(subs(H=1.,h=1./(N+1),Eq[i]),i=O..N+1)},{seq(y[i]=O..1.O,i=0..N+1)});
SI yo = 1., y, = .7974683557, y3 = .6455696221, y, = .6835443055 )
> fsolve({seq(subs(H=2.,h=1./(N+l),Eq[i]),i=O..N+1)),{seq(y[i]=0..1.0,i=0..N+1)});
{ 0= l., y, = .5421686749, y = .2530120485, y= .3253012050 )
C Note that same command can be used for nonlinear ODEs with non-linear boundary conditions.

Partial Differential Equations (Heat conduction in a semi-infinite domain)
[ > restart:with(linalg):
Consider the transient state heat conduction equation (references 2,3, 14-16)

> eq:=diff(u(x,t),t)-alpha*diff(u(x,t),x$2)=0;

eq:= \u(x,t) -a u(x,t) =0

where a is the thermal diffusivity (- ) and u is the dimensionless temperature. The initial and boundary conditions are
> u(x,0):=l;bcl:=u(0,t)=0;bc2:=u(infinity,t)=defined;
u(x, 0):= 1
bcl := u(0, t)= 0
bc2 := u(o, t) = defined
[ Now the Laplace transformation package is called and the governing equation is converted into Laplace domain.
r > with(inttrans):eqs:=laplace(eq,t,s);

Fall 2000

APPENDIX: Solving Differential Equations with Maple

eqs := s laplace(u(x, t) t, s) a laplace(u(x, t), s) = 0

[ Note that the initial condition is included. For brevity let's use the variable U.
> eqs:=subs(laplace(u(x,t),t,s)=U(x),eqs);

eqs := s U(x)- I a U(x) =0

[ Next transform the boundary conditions into the Laplace domain
S> bcl:=laplace(bcl,t,s):bcl:=subs(llaplace(u(0,t),t,s)=U(),bcl);
bcl := U(0)= 0
Next, the eqs equation given above is solved by using the matrix exponential method with x as the independent variable
instead of t (s is a parameter in this case).
> A:=matrix(2,2,[0,1, s/alpha,0] ) :b:=matrix(2,1,[0, -/alpha] ) :y0:=matrix(2,1,[0,c2]

> mat:=exponential(A,x) :invmat:=evalm(subs (x=x-xl, evalm(mat))):matl:=evalm(invmat&
*evalm(subs (x=xl,evalm(b)))):mat2:=map(int,matl,xl=0..x) :mat3:=evalm(subs(xl=x,m
> sol:=evalm(evalm(mat&*y0)+mat3);

la -e + e )c2 -2+e e +e
2 as 2 s
$0 := ( /"Iil'" f -"l

I a) I a) 1 a-l+e ;e
-e +-e c2--
2 2 2 .
so!' 2i (0) e(ise

[ Our solution is given by the first row of sol
> uu:=expand(sol[1,1]);

1 I c2 e I ac2 I e 1
Stas2 2 s 2 s 2
Va-s ea s e
Since we are dealing with the semi-infinite domain, from the boundary condition at the infinity (bc2), the solution has to be

finite when x goes to -. Consequently, the coefficient of e in the equation uu above must be zero. This requirement
yields an expression for c2 and a simplified uu equation.
> eqc:=coeff (uu,exp(sqrt(s*alpha)*x/alpha));c2:=solve(eqc,c2);
1 ac2 1 1
eqc :2--2s
2 as

> uu;
1 1

[ Now inverting uu back to time domain yields a solution.
> Ut:=invlaplace(uu,s,t);

Ut:= ( lim r erx +1
4 -11 e 2 Ta V- e 2 t ))
SMaple does not give the simplified solution since we haven't specified the signs of x and a. We just have to specify that
they are positive. We use dummy variables (xl and al) for this purpose.

Chemical Engineering Education

APPENDIX: Solving Differential Equations with Maple

S> uu: tsubs(alpha=alphal,x=xl,uu) :assume(xl>0,alphal>0) ;Ut:=invlaplace(uu,s,t);

Ut := -erfc + I

[ Once the inverse is obtained, the dummy variables can be changed back to the original variables.
> Ut:=subs(xl=x,alphal=alpha,Ut);Ut:=convert(Ut,erf);
l x
Ut:=-crfc( r- )+ I

Ut e4= 2e 4-

Ut is the expected solution (reference 2,3,14-16). For a given value of a, a three dimensional plot of Ut as a function of x
and t can be obtained.
S> with(plots):plot3d(subs(alpha=0.001,Ut),x=l..0,t=500..0,axes=boxed,labels=[x,t,"

1 0.8 0.6,0.4 0.2 0

[ Analytic method of lines for PDEs (Heat transfer in a finite medium)
[ > restart;with(linalg):
[ Consider heat transfer in a finite medium (references 14, 21, 22)
[ > ge:=diff(T(x,t),t)=alpha*diff(T(x,t),x$2):
[ The boundary and initial conditions are
> bcl:=H*(TO-T(O,t))=-k*Diff(T(O,t),x);bc2:=Diff(T(1,t),x)=O;IC:=T(x,O)=100;
bcl :=H(TO-T(0,t))=-k -T(0,t)

bc2 := H := T( t) = 0
bc2:=aT( 1,)=0

IC:= T(x,0)= 100
The governing equation is discretized along the x-axis from i = 1 to N interior node points. N = 2 node points are used for
> N:=2:eq[0]:=H*(TO-y[0]) = -k*(-y[2]+4*y[l]-3*y[0])/(2*h):
> for i from 1 to N do eq[i]:=Diff(y[i],t)= subs(diff(T(x,t),x$2) =
(y[i+l] -2*y[i]+y[i-] ) / (h^2) ,rhs(ge)) ;od:
[ Now the boundary conditions are used to eliminate the end values

2HTOh-ky2 +4ky,
Yo 2Hh+3k

Fall 2000

APPENDIX: Solving Differential Equations with Maple

4 1
y 3:=y2- Y y
3 3
> for i from 1 to N do eq[i]:=eval(eq[i]);od;

a 2 2 y+ 2HTOh-ky2+4ky
O 28- 24y+ 2Hh+3k
eq, := -ty, -
S2 2
a 3 3
eq, :=-y2=
at h2
The governing equations at the interior node points (i = I.. N) can be expressed in matrix form (equation I) and solved
using equation 2.
[ > eqns:=[seq(rhs(eq[j]),j=l..N)]:Y:=[seq(y[i],i=1..N)]:A:=genmatrix(eqns,Y,'bl'):
[ > b:=matrix(N,1):for i from 1 to N do b[i,1]:=-bl[i];od:evalm(b):
[ Note that the matrix is not printed for saving space. The parameters are entered here.
C > L:=1.00:h:=evalf(L/(N+1)):alpha:=2*10. (-5):H:=25.0:k:=10.0:TO:=0:
[ > A:=map(eval,A):b:=map(eval,b):
[ The initial condition is entered now
[ > YO:=matrix(N,1):for i from 1 to N do YO[i,1]:=evalf(subs(x=i*h,rhs(IC)));od:
[ The solution is found out now (equation 2)
> mat:=exponential(A, t): invmat:=evalm(subs (t=t-tl, evalm(mat) )) :matl:=evalm(invmat&
at2)) : Y:=evalm(evalm(mat&*YO)+mat3);
[ 14.06250002 e('-'OYM""xm)"' + 85.93749998 e(-'XX "'257142 ")
= L 109.3750000 e'-.IX"XM2571428'76' 9.37500002 e'-'" '-W""""Xx'") J
Note that we obtain the temperature at different node points as a function of time (analytical in time and numerical in x).
The values at the node points can be plotted.
[ > with(plots):for i from 1 to N do y[i]:=simplify(eval(Y[i,1]));od:
[ > for i from 0 to N+1 do p[i]:=plot(y[i],t=0..6000,thickness=3);od:
> display((seq(p[i],i=0..N+))},axes=boxed,labels= t,T]);





0 1000 2000 3000 4000 5000 6000
[ By increasing N, more accurate solutoins can be obtained. N = 6 is found to be sufficient for this case.

Chemical Engineering Education

The Chemical Engineering Division Lectureship
The Ray W. Fahien Award Sponsored by Union Carbide Corporation
Sponsored by 3M Corporation Arvind Varma
University ofNotre Dame
Francis J. Doyle, III
University ofDelaware
Univ y of D e William H. Corcoran Award

Professor Doyle was specifically rec- Sponsored by Eastman Chemical Corporation
ognizedfor his contributions to chemi- Barbara M. Olds and Ronald L. Miller
cal engineering education through soft- Colorado School of Mines
ware development, innovative uses of
the world wide web, excellent teaching,
and effective mentoring of students. The Joseph .l. Martin Award
This award is given annually to a edu- Alec B. Scranton
cator who has demonstrated a scholarly Michigan State University (present address: University of Iowa)
approach to teaching and learning and
who has shown evidence of vision and
contribution to chemical engineering edu- CA CHE Award
cation. Nominees are evaluated based on
outstanding teaching effectiveness and Mordechai Shacham
educational scholarship. The award re- Ben-Gurion University of the Negev
cipient should have made significant con-
tributions to chemical engineering edu- General Electric Senior Research Award
General Electric Senior Research Award
cation that go beyond his or her own
institution. Nicholas A. Peppas
Purdue University

2000 ASEE Fellow Member Honoree William B. Krantz, University of Cincinnati

Outstanding New Faculty Awards
Illinois-Indiana Section John E. Wagner, Tri-State Univesity
Middle Atlantic Section Stephanie Farrell, Rowan University
Rocky Mountain Section David W. Marr, Colorado School of Mines
Southeast Section S. Michael Kilbey, Clemson University

2000 Section Outstanding Teaching Awards
Illinois-Indiana Section R. Neal Houze, Purdue University
Southeast Section Douglas E. Hirt, Clemson University

Thomas C. Evans Instructional Unit Award
Raj Rajagopalan, University of Florida

Fall 2000

1 -1classroom



New Method for Rich-Phase Gas Absorption Columns

University of Newcastle Callaghan NSW 2308, Australia

he McCabe-Thiele method for analyzing binary ab-
sorption and stripping problems is taught as a stan-
dard part of most undergraduate chemical engineer-
ing degrees. The case of mutually insoluble carrier streams
is usually considered first, with the problem set out as illus-
trated in Figure 1. V and L are the mole (or mass) flow rates
of the vapour and liquid streams (or light and dense streams
in the case of liquid-liquid extraction), a and b refer to the
top and bottom of the column, and x and y are the mole (or
mass) fractions of the soluble component in streams L and V
respectively.'" The operating line is obtained by performing
a material balance around stages 1 to n of the column*

( L x+YaVa-xaLa(1)
=(V) V (1)
In general this is a curved line, although for lean-phase
systems (where the concentration of the soluble component
is always less than 10%), the magnitude of the stream
flowrates, L and V, remain nearly constant and so the operat-
ing line can be approximated as a straight line:

Y= a+ [)(x- a) (2)

Students are often required to determine the theoretical
minimum liquid flowrate, Lamin, required in order to achieve
a desired separation. This is the liquid flowrate at which an
infinite number of stages would be required and it occurs
when the operating line just touches the equilibrium line (the
"pinch" point).
For lean-phase problems, the solution is trivial. The stu-

SFor staged problems, the compositions and flows entering and
leaving the control volume below stage n are usually written as
x, y.,,, L, and V ,. In this paper we use the synbols x, y, L, and
V, which are for packed columns, but the two sets of terms are

dent only needs to draw a straight operating line from the
known conditions at the top of the column (xa,Ya) which just
touches the equilibrium line. If the equilibrium line is also
straight (e.g., Henry's law, y= mx) then this will occur at end
b of the column where Lb leaves in equilibrium with the
entering gas Vb at the point xb=y/m (see Figure 2a).
For rich phase systems (concentrations greater than 10%),
however, the operating line has significant curvature be-
cause the ratio of L to V varies down the length of the
column. In this case, assuming the required operating line
passes through the point (ybm, Yb) may not always be cor-
rect. If the operating line is concave up then it is possible that
the operating line may cut the equilibrium line at some point
between y, and y, (see Figure 2c), and so the operating line
through (y/m, Yb) gives too low an estimate of L,min. What is
more, the student only becomes aware of this error if they
take the time to plot the operating line for the minimum
liquid flowrate case, whereas they often without checking go
on to solve the main part of the question which involves
calculating the number of stages required when La is some
multiple of Lmi.
In this case where the operating line is concave up (or
concave down for stripping problems), to find the operating
line which just touches the equilibrium line the students
must either adopt a lengthy trial-and-error approach, or else

Simon Iveson received his PhD in Chemical
Engineering from the University of Queensland,
Australia, in 1997. Since then he has been a
research fellow and part-time lecturer within
the Centre for Multiphase Process in the De-
partment of Chemical Engineering at the Uni-
versity of Newcastle, Australia. His research
interests are in the field of particle technology,
with his focus being on the agglomeration of
fine particles by the addition of liquid binders.

Copyright ChE Division of ASEE 2000

Chemical Engineering Education


they must solve the problem graphically12'31 by first convert-
ing the problem into mole (or mass) ratios, X and Y, where
X = x/(1-x) is the moles of solute per mole inert carrier fluid
and Y = y/(1-y) is the moles of solute per mole of inert
carrier vapour (0 < X,Y < -). When mole ratios are used, the
liquid and vapour flow rates are given as L'=(1-xa)La and
V'=(1-y)Va, the moles of solute-free liquid and vapour flow
respectively. For mutually insoluble solute streams, L' and
V' remain constant, and so the operating line is a straight
line given by the equation
V'(Y-Ya)=L'(X-Xa) (3)
Once the equilibrium data has also been converted into
mole ratios and plotted, the minimum condition can easily
be found graphically, using a ruler to find the straight line
starting at (Xa, Ya) which touches the equilibrium line. The
slope of this line is L'V', from which L,min can be calcu-
This paper presents a new analytical approach for finding
the minimum liquid flowrate in rich phase problems that
does not require converting the problem into mole ratios.
The new method requires that an analytical expression for
the equilibrium line be known and that this remains constant
through the length of the column, i.e., the column must be
operating isothermally. This method involves rearranging
Eq. (1) into an explicit expression for y in terms of x and
solving to find the point at which it just touches the equilib-
rium line. This analytical method can be taught to students to
complement the traditional graphical approach.

In most text books, the equation for the operating line is
left as shown in Eq. (1). This equation cannot be used imme-
diately to solve for y in terms of x, because L and V are both
also functions of x for the rich phase case.
Since the flow of inert carrier fluid remains constant for

mutually insoluble streams, (l-x)L = (1-xa)La. Therefore

L- (-xa)La (4)
(1- x)

A total material balance around stages 1 to n gives V = L +
Va L,, which when using Eq. (4) can be re-written as

(1- x)

Substituting Eqs. (4) and (5) into Eq. (1) and rearranging
gives an explicit equation for y in terms of x as the only

(La )
YaVa xaL +x(La yaVa) Y a) (x-a)+Ya(1-x)
Va -XaLa+x(La-Va) ( La x-xa)+(1-x)
Va )( a+( I

Eq. (6) can also be differentiated to give the equation for
the slope of the operating line at any point

(L a)
dy LaVa(xa-1)(ya-1) a(1xa)(1-ya)
S[Va-XaLa +x(La -Va)] La) Xa
aa )(-

Equation (6) is simple to derive, requiring only a substitu-
tion and rearrangement of Eq. (1) or (3). Although trivial to
derive, however, it is not presented in this form in any of the
standard introductory texts on separation processes.""51 Its
usefulness lies in the fact that as an explicit function for y in
terms of x, it is easy to differentiate, giving Eq. (7), which is
novel. Equations (6) and (7) are extremely useful because
they can be used directly to solve for y and dy/dx at any
point down the column in terms of only one variable, x.
Choosing end a of the column as the reference point was
arbitrary. These equations can equally well be written in

4 Figure 1. Schematic of ab- A Figure 2. Operating and equilibrium line plots
sorption/stripping column show- for gas absorption: (a) lean phase with straight
ing definitions of L, V, a, b, x, operating line; (b) rich phase case with operating
and y (after McCabe, et al.,'11") line concave down; and (c) rich phase case with
operating line concave up.

Fall 2000

V,y Lx


Vb,V Lb Xb

terms of end b (or in terms of any other known point along
the length of the column) by simple substitution of Lb for La,
xb for Xa, etc.
Provided that we have an analytical expression for the
equilibrium relationship which is constant through the length
of the column, these two equations can now be used to
analytically find the minimum liquid flowrate, La, mi, re-
quired to achieve a given separation. The simplest case
where the equilibrium line is given by Henry's law (y* =
mx), will now be considered as an example.
La,.m occurs when the operating line and equilibrium line
touch at a single point between y, and yb. This intersection
point can be found analytically and is given by (see Appen-
dix A)

La,min -P--2 -4
Va 2a (8)
where a=(1-mxa)2, P=4m(ya+xa)-2(m+ya)(mxa +1), and
8=(m-ya) For stripping problems where the operating
line is below the equilibrium line, Vb,,, is found by

Lb __0+ 132 -4ab
Lb -P+ P(9)
Vb,min 2a
where a=(1-mxb)2, P=4m(yb +Xb)-2(m+yb)(mxb +1), and
To decide whether using Eq. (8) or (9) is necessary, it must
be first determined if the pinch point lies between y, and b,,
or at Yb. The general solution strategy for finding L,min in any
rich-phase gas absorption problems is as follows.
Begin by assuming that the pinch point where the operat-
ing line just touches the equilibrium line is at the base of the

Solution Procedure for Finding L .m.n or Vbm for Rich-Phase
Absorption or Stripping Problems Where the Equilibrium Line
is Given by Henry's Law and the Two Carrier Phases
are Mutually Insoluble

Absorption Problem
(x,, Ya, V, Yb, all known)

Step 1

Step 2

Step 3a

Stripping Problem
(yb, Xa, L, xb, Lb all known)

Assume Xb = ,b/m. Calculate Assume ya = mx,. Calculate
(1i-xb )(YbVb -YVa ) V (1-ya)(xbLb --La,)
(Xb-Xb) (Yb-Yb)

Calculate dy/dx at (xb,yb) Calculate dy/dx at (x,,ya)
using Eq. (6) using Eq. (6)
If dy/dx < m, then Lm,_ is If dy/dx > m, then Vb,.m is
the La found in Step 1. the V. found in Step 1.

Step 3b If dy/dx > m, the L ,in is
found using Eq. (7).

If dy/dx > m, then is
found using Eq. (8)

column. Therefore x, = yb/m and La is found by an overall
material balance around the column:
In = Out (at Steady State)
Solute: ybVb + xaLa = bLb + aV
Inert Liquid: (-xa)La = (-xb)Lb
Re-arranging and solving for La gives:

S(1-Xb)(ybVb -aVa) (10)
(xb ) (-X
Step 2
Calculate the slope of the operating line at x, = y/m using
Eq. (7).
Step 3a
If the slope of the operating line at x, = y/m is less than
the slope of the equilibrium line (i.e., dy/dx < m), this
indicates that the operating line has crossed the equilibrium
line from above, as shown in Figure 2b, so the La found in
Step 2 is the correct Lanin-
Step 3b
If the slope of the operating line is greater than the slope of
the equilibrium line (i.e., dy/dx > m), then this indicates that
the operating line is intersecting the equilibrium line from
below, as shown in Figure 2c. In this case, Eq. (8) can then
be used to find the correct minimum liquid flowrate.
For stripping problems, the operating line lies below the
equilibrium line and the full conditions are known at end b,
but not end a. The aim is to find Vb.min and the requirements
for the slope of the operating line at the point of intersection
are reversed. The solution procedures for both absorption
and stripping problems are summarized in Table 1. A worked
example problem illustrating both this solution procedure
and the traditional approach is given in Appendix B.
The above solution procedure can be easily adjusted to
consider other analytical expressions for the equilibrium
line, y* = f(x). If the equilibrium line is given by equilibrium
data which does not readily fit any simple analytical expres-
sion, then the student has no choice but to convert the prob-
lem into mole ratios and solve graphically.

The new method proposed is fully analytical. However,
the intuitive understanding behind the derivation that stu-
dents need to appreciate is based on a graphical understand-
ing of the problem. Hence, it cannot replace the traditional
graphical approach using solute-free coordinates. It is, how-
ever, complimentary and provides students with a different
set of tools for tackling such problems. In addition, the
derivation of this method serves to remind students that the
basic tools of analytical geometry they learned at school can
be applied to apparently unrelated engineering problems.

Chemical Engineering Education

Although no formal survey of students was performed, the
author's informal impression after lecturing one class has
been that many of them preferred to use analytical expres-
sions, rather than having to convert the problems into mole
ratio units and then use graphical methods.
Equation (6) is not only useful for finding the point at
which the operating line touches the equilibrium line, but it
can also be given to students to help them plot the curved
operating lines that occur in any rich-phase problem. This is
required in order to be able to step off the number of stages
via the McCabe-Thiele method, or to perform the numerical
integration required to find the number of transfer units in a
packed column.
Even if the full analytical method is not used, the equation
for the slope of the operating line, Eq. (7), is valuable
because it enables students to test whether the end point
(y,, ybm) is the correct pinch point without having to plot
the full operating line.
Equations (8) and (9) are also potentially useful for soft-
ware packages for computer-based learning packages where
each student in a class can be given different computer-
generated problems to solve independently and then enter
their answers into the computer for checking.

Explicit equations for the operating line and its slope in
rich-phase gas absorption and stripping problems have been
derived with x as the only variable. These expressions, al-
though trivial to derive, are not presented in any of the
standard introductory texts on separation processes. They
have been used to develop a new analytical method for
finding the minimum liquid flowrate in rich-phase problems
without needing to convert the problem into solute-free co-
ordinates and then use graphical methods.
The method presented here is restricted to cases where
there is an analytical expression for the equilibrium line,
which remains constant along the length of the column (i.e.,
isothermal operations). It is also required that the two carrier
phases are mutually insoluble. The method is ideally suited
for use in computer packages for teaching students how to
solve these problems. The explicit equation for the operating
line is also useful for plotting the curved operating line in
order to step off the number of equilibrium stages via the
McCabe-Thiele method, or for numerical integration to find
the number of transfer units in packed columns.

1. McCabe, W.L., J.S. Smith, and P. Harriot, Unit Operations
in Chemical Engineering, 5th ed., McGraw-Hill, New York,
NY (1993)
2. Treybal, R.E., Mass Transfer Operations, 3rd ed., McGraw-
Hill, New York, NY (1981)
3. Sherwood, T.K., R.L. Pigford, and C.R. Wilke, Mass Trans-
fer, McGraw-Hill, New York, NY (1975)

4. Coulson, J.M. and J.F. Richardson, Chemical Engineering,
Volume 2: Particle Technology and Separation Processes,
4th ed., Pergamon Press (1991)
5. Edwards, W.M., "Mass Transfer and Gas Absorption" in
Perry's Chemical Engineers' Handbook, 6th ed., R.H. Perry
and D. Green (eds), Mc-Graw-Hill, New York, NY (1984)

Appendix A
The Analytical Solution for Lmin or Vmin

The minimum liquid or vapor flowrate occurs when the
operating line just touches the equilibrium line y = mx
between ya and Yb. This point occurs when the two lines
intersect, which from Eq. (6) is at

y=mx= -La L
Vj (x-Xa)+(l-x)

Rearranging in terms of x gives:

2 (La ) (La (La _
x2 m -l+x [m+ya- (La)(mxa+)] +LV)xa-Ya]=0


This is a quadratic equation of the general form
ax2+bx+c=0. We want the case where the operating line only
just touches the equilibrium line. This occurs when there is
only one point of intersection which is at b2-4ac = 0. This

(L'2 (1-mxa)2 +La )4m(ya +Xa)-2(m+ya)(mxa +)]

+(m-ya)2=0 (A3)

This is a quadratic equation of the form

a(La/Va)2 +P(La/Va)+8=0
which can be solved for L/Va to give

La _-p3f2-4a6
Va 26


where a=(1-mxa)2, P=4m(ya +Xa)-2(m+ya)(mxa +1), and
8=(m-ya)2. Unfortunately the square root term does not
simplify, so equation (A4) is best left in terms of a, P, and 8.
Equation (A4) gives two solutions for L/Va when the
operating line just touches the equilibrium line at one point.
However, only one of these is the correct point of touching
between y, and yb. For absorption problems, the negative
root should be taken, which will give the solution for (La)min/
Va. For stripping problems, a, P, and 8. should be written in
terms of xb and Yb and the positive root taken to give the
solution for L/(Vb)m,,.

Fall 2000

Appendix B
Worked Example Comparing the New Method and the
Traditional Graphical Method

A dry cleaning plant produces an air stream containing 2
mol% acetone. Regulations require that the concentration of
acetone be reduced below 0.1 mol% before this stream is
released to the environment. This is to be done by absorption
with water in a countercurrent packed column. The water
enters the column already containing 0.5 mol% acetone. The
equilibrium relationship for acetone in air and water is given
by y = 0.1246x where x and y are the mole fractions of
acetone in the aqueous and vapour phase respectively. Find
the theoretical minimum liquid flowrate required to achieve
this separation (these figures are given as examples only).
First it is necessary to find the flowrate of the gas stream
exiting the column. We will assume that the water and air are
mutually insoluble and take a basis of Vb = 100 moles and
use y, = 0.001. At steady state, a material balance around the
column on the air gives (1-ya)Va = (1-yb)Vb from which
Va = (1-0.02)(100)/(1-0.001) = 98.10

The New Analytical Method
Step 1
We will initially assume that the minimum liquid flowrate
occurs when the aqueous stream leaves in equilibrium with
the entering gas stream, which gives
x = y/m = 0.02/0.1246 = 0.1605.






0 0.05 0.1 0.15 0.2
X (liquid phase mole ratio)

Note that since xb > 0.10, this is a rich-phase problem and
the operating line will be significantly curved. Equation (9)
can now be used to find L,

S (Xb-Xa)


Step 2
Equation (6) is used to find the operating line slope at the
point (xb,yb)

dx La ) 0(-xa)(- ya)
dy a [(La (x -xa)+(1 -Xb)]2

.1 '(1- 0.005)(1- 0.001)

[9 10.7 (0.1605 -0.005) +(1-0.1605)


Since dy/dxlb > m, this indicates that the operating line is
crossing the equilibrium line from below, so we have under-
estimated La,in. Go to step 3b.
Step 3b
Solve for L,,a. using Eq. (7)

O = (1 mxa)2 = [- 0.1246(0.005)]2 = 0.9988
P= 4m(ya +Xa)-2(m + ya)(mxa +1)
= 4(0.1246)(0.001+ 0.005)
2(0.1246 + 0.001)[0.1246(0.005)+ 1]
= -0.2484
= (m- ya)2 = (0.1246- 0.001)2 =0.01528

La.m = Va. 2c

0.2484- (0.2484)2 -4(0.9988)(0.01528)

Therefore, the theoretical minimum liquid flowrate is 10.94
moles of water per 100 moles of entering gas. Note that this
is 6% higher than the original estimate found by assuming
that the liquid exits in equilibrium with the entering gas. The
magnitude of this error depends on the degree of curvature
of the operating line.
Traditional Graphical Approach
The equilibrium line is plotted on X-Y coordinates, Figure

Chemical Engineering Education

..... .. 0.0204 .......................... .

Equilibrium Line
-*-Operating Line


Xb= 0.18
W .

Figure 3. Plot of mole ratios Y vs. X showing the
traditional graphical approach to find the operat-
ing line, which just touches the equilibrium line.


3, by expressing it as

I+Y l+X


The bottom end of the operating line (Xa,Ya) is found by
converting xa = 0.005 to Xa = xa/(1-xa) = 0.00503 and y, =
0.001 to Ya = 0.00100. The top end of the line is at Yb = yd
(1-yb) = 0.0204. The line through (Xa,Y,) that just touches
the equilibrium line is then found graphically (see Figure
3). From Figure 3, the operating line which just touches
the equilibrium line passes through Xb 0.18 which
gives xb = 0.152.
The minimum liquid flowrate is now found by an overall

material balance.

In = Out
Acetone ybVb+XaLa = YaV, +XbLb
0.02(100)+0.005La = 0.001(98.10)+0.152(Lb)


1.9019 = 0.152Lb-0.005La
(1-xa)La = (1-xb)Lb
0.995La = 0.848Lb



Solving the simultaneous Eqs. B and B2 gives the mini-
mum liquid flowrate of La = 10.97 moles per 100 moles feed
gas. This compares well with the exact analytical solution of
10.94. It should be pointed out that the traditional solution
method takes more time to perform because of the require-
ment to plot the data. n

book review

Engineering Flow and Heat Exchange
Revised Edition
by Octave Levenspiel
Plenum Press, New York and London (1998)

Reviewed by
Gabriel I. Tardos

This is the first revised edition of this book, first published
in 1984. Professor Levenspiel should be commended for
producing such an excellent text, written specifically for
engineering students. The book is a pleasure to read and
offers several amusing problems, all stated in the language
of students, with explanations and examples they can easily
understand. Very few texts in engineering can make such a
claim. I have used this text exclusively since 1992 in my
teaching of unit operations to chemical engineering students.
The material is broad enough, however, to also be used in
mechanical engineering, and perhaps in civil engineering
courses as well, to teach flow and heat transfer.
Students (especially undergraduates) tend to sell used text-
books once they finish a subject and pass their final exami-
nation. I found, with great pleasure, that Engineering Flow
and Heat Exchange was not one of those books; seniors use
it in their design courses and many graduates keep the book
as a reference. This is obviously due to the wealth of
information in the book and the ease with which the infor-
mation can be retrieved and used. Inclusion of compressible

Fall 2000

and non-Newtonian fluid flow in the fluid-mechanics sec-
tion and direct-contact heat exchangers in the heat-exchang-
ers section is a substantial achievement and significantly
adds to the usefulness of the text.
One example of the book's unique approach to explaining
a complex concept through humor and straightforward, easy-
to-understand language is illustrated by how Professor
Levenspiel explains the concept of equivalent average slurry
density in the problem "Counting Canaries Italian Style."
The "slurry" consists of canaries flying in the air inside a
closed container. Measuring the pressure before and after
the canaries are airborne, and using the Bernoulli equation,
gives the change in density and therefore the number of
"particles" (birds). Ingenious!
As already mentioned, the book is divided into a section
on fluid mechanics and a section on heat transfer. The first
part includes basic equations for isothermal flowing systems
in Chapter 1, and as an example, flow of incompressible
Newtonian fluids in pipes and around solid immersed ob-
jects in Chapters 2 and 8, respectively. Unlike other similar
texts, the theory is kept short and the assumption is that the
student has taken a prior course in fluid mechanics. It is
assumed, for example, that the student is familiar with the
concept of the Fanning friction factor.
Chapters 3 and 4 address compressible flow of gases
(through material taken mostly from thermodynamics) and
Continued on page 355.


SM classroom


Distilled From My First Few Years of Teaching

Northeastern University Boston MA 02115-5000

All I really need to know about teaching I learned in
... kindergarten?"1 For me, nothing prepared me
better for my role as a teacher than my first few
years of teaching. On one hand, I could clearly identify with
my students, who also faced a new learning situation. On the
other hand, I could clearly see the challenges that needed to
be bridged by myself as a teacher. Those first few years of
teaching heightened my awareness of the gap between what
a teacher teaches and what the students learn. I wrestled with
a number of issues, including
How to encourage students to learn concepts and to
understand relationships between variables, rather thatjust
"plugging numbers into equations
How to teach problem-solving skills that would enable
students to solve a variety of problems
How to keep students motivated by balancing encouragement
with "threats"
I began my search for the guiding principles that underlie
good teaching by attending several workshops and by read-
ing articles and references on effective teaching and learning
(see the end-list of references). It was my first-hand experi-
ence in teaching, however, that brought those guiding prin-
ciples to life. The following paragraphs highlight some of
the insights and experiences that proved helpful during my
formative years of learning to teach.
My perspective of my role as a teacher was changed one
day when I found myself in a learner's situation. On this
particular day, I was to meet a group of friends at an Italian
restaurant. I had been to this particular restaurant a number
of times, but each time I had been a passenger in the car-I
was busy listening, talking, gazing out the window, and
looking at other passengers in the car. Now it was my turn to
drive, and I found I could not remember exactly how to get
Carolyn W.T. Lee is currently an assistant professor at Northeastern
University. She pursued her undergraduate education at the University of
Kansas and her graduate education at Cornell University. She began her
teaching career as a Visiting Professor at Rose-Hulman Institute of Tech-
nology. Her research interests are in biochemical engineering, specifi-
cally the production of medicinal compounds from plant cell cultures.
Copyright ChE Division of ASEE 2000

there! Does this sound familiar? Now, imagine yourself, the
teacher, as the driver and your students as the passengers in
your classroom. My experience of being the passenger, or
the "learner," helped me to formulate and adopt four guiding
principles for teaching and interacting with students:
Choose the best path for learning
Outline the path taken
Engage the students in their own learning
Promote an environment that encourages questions,
learning, and respect for others

When choosing the best route to an end destination, the
driver should consider if the route is interesting and scenic
and if it minimizes distance, or if it contains a number of
confusing turns or potential delays. Similarly, one of the
responsibilities of a teacher is to choose the best way to
convey an idea or a concept. Whenever possible, when illus-
trating an important idea I enjoy using an in-class demon-
stration or a real-life example, or developing a physical
picture to capture the interest of the class. For example, in a
fluid mechanics course, the mechanical energy balance is
used to predict the water flow rate through a siphon.[21 Be-
fore the demonstration of a siphon, the class is asked to
determine how the water flow rate is affected by the position
of the tube outlet. They are then asked to estimate the water
flow rate through the smooth tube when the outlet of the tube
is placed a certain distance below the water level in the tank.
Their estimate, obtained by using the mechanical energy
balance, is then compared to the measured flow rate. They
are then asked to explain the differences. Demonstrations
and real-life examples are fun ways of presenting concepts;
moreover, they serve to connect classroom learning to real-
life applications.
In addition to choosing a scenic route, the best path for
learning should also be one that minimizes frustrations and
"busy work"; one that includes important "landmarks." For
example, derivations illustrate the powerful tool of begin-
ning with basic principles and arriving at a description or

Chemical Engineering Education

model of a given phenomenon. But since students often
become frustrated, bored, or lost when doing derivations, to
teach them how to derive relationships, a handout with the
partial derivation is distributed. It includes intermediate re-
sults (i.e., landmarks) and some of the reasoning behind the
individual steps in the derivation (i.e., directions). The first
direction in doing a derivation is to develop a physical feel
for the relationship between the variables. For example, how
would you expect pressure drop across a pipe to change with
pipe length, flow rate, and fluid properties-and why? The
last landmark in the derivation is to check the reasonable-
ness of the derivation, i.e., check the initial predictions with
the results from the completed derivations.
Pointing out the reasoning and providing intermediate an-
swers in solving a problem help students come up with their
own plan for solving problems. These handouts teach impor-
tant problem-solving skills while at the same time reducing
the roadblocks that many students encounter in derivations
or in solving problems. Out of the classroom, thought-provok-
ing questions, hints, and intermediate answers for homework
problems can also be made available on the courses's web site.
In addition, whenever possible, MAPLE, Mathematica, or
EXCEL can be used to minimize the work associated with
trial-and-error calculations while illustrating the relation-
ships between variables. For instance, in determining an
economic pipe diameter, the pumping costs associated with
skin frictional losses and the pipe costs are calculated at a
given pipe diameter.31 These calculations can then be re-
peated at other pipe diameters using an EXCEL spreadsheet
rather than being repeated manually. A plot can then be
generated on EXCEL to illustrate the sensitivity of the pump-
ing costs and the piping costs with changes in pipe diameter.

As the driver, I have a fairly good idea of how I am going
to arrive at my destination. Not having traveled this way
before, however, my passengers have no such picture. Simi-
larly, I have a good idea of the important concepts that
should be covered in each of my courses and how these
concepts are connected and related. This is an overall per-
spective on the course that my students do not have. Hence,
one of my guiding principles in teaching is to outline the
path we will be taking in the course.
For example, in my course on fluid mechanics, I use a
flowchart of a chemical process to point out the problems we
will analyze in the course. The concepts of fluid mechanics
that are relevant to the operation and design of a chemical
process may include estimating frictional losses through pipes,
various fittings, and various unit operations such as a packed
column, and then using these estimates of frictional loss to
select an appropriate pump size and an appropriate impeller
speed. As each topic is covered in the course, we refer back
to the original flowchart to illustrate the relevance of the

concepts and to gauge the progress we have made in the
course. The path is outlined at other levels as well, such as
outlining the strategy for solving a particular problem or
outlining the lecture for that day.

I am best able to retrace an unfamiliar route on my own if
on a previous trip I was involved in either determining the
route traveled or in locating the relevant landmarks and road
signs along the way. Similarly, students are best able to
understand the concepts laid out in a lecture if they are
actively thinking through the individual points of the lecture
or are engaged in solving problems along the way. Convey-
ing the concepts in an interesting way, using relevant ex-
amples and applications to real life, outlining the points of a
lecture in an organized and simple-to-follow manner are essen-
tial in keeping the students mentally engaged during a lecture.
Even the best-laid plans, however, may not be sufficient.
When appropriate, students should be guided and encour-
aged to arrive at the concepts and conclusions themselves
through a sequence of well-posed thought questions.14'51 Co-
operative learning involves this type of activity since the
students ask and answer each other's questions in arriving at
a solution.161 Students actively involved in the solving of
problems, as compared to those following the professor's
solution, demonstrate the highest retention rate. Adequate
guidance, thought-provoking questions, and intermediate
answers are needed in order to reduce the frustration that can
occur during problem-solving.
To make the most of the class time, students must keep up
with the course in order to follow the lecture and to be well
prepared for problem solving during the class. Daily reading
assignments, frequent in-class quizzes, and small but fre-
quent homework assignments discipline students to keep up
with the course.

My own experiences as a learner taught me the importance
of a learning environment that focuses on and encourages
growth and development. Students will feel open and free to
ask questions in class or during office hours if they sense
that I really want to understand their questions and am en-
thusiastic and patient in responding to them. I try to address
each question as a good question. I realize that being a
different type of learner or being unaware of what is really
confusing them may make it difficult for me to initially
understand why they asked a particular question; therefore,
my answer may require multiple explanations or require
probing with further questions. In any case, I believe stu-
dents should be encouraged and applauded when they choose
Continued on page 349.

Fall 2000



A Perspective

Cornell University Ithaca, NY 14853-5201

Chemical engineers have made important contribu-
tions to a variety of problems relevant to the phar-
maceutical and biotechnology industries. Their broad
educational background has enabled chemical engineers to
work on upstream problems such as the creation and screen-
ing of large libraries of proteins for drug discovery or the
design and efficient operation of bioreactors, as well as
downstream problems in separations and recovery. The de-
velopment of new technologies in molecular biology and
genetics provides an opportunity to explore some of the
most basic information about an organism (i.e., the genome)
with the goal of understanding how the DNA sequence of an
organism relates to its ability to function. Armed with this
information, the biochemical engineer can begin to design
more efficient products and processes.
As with many such developments in science and engineer-
ing, these new opportunities are coupled with several chal-
lenges. Among the challenges facing modem biology are
difficulties in organizing and extracting useful information
from tremendous amounts of raw data, as well as the devel-
opment of mathematical models that will effectively simulate
experimentally observed phenomena and provide a better un-
derstanding of complex cellular processes. These issues have
motivated the emerging discipline of bioinformatics.
Bioinformatics encompasses a wide range of approaches,
techniques, and philosophies, and the chemical engineer has
an opportunity to make a significant impact both by working
in areas within biochemical engineering and by working in
collaboration with colleagues from the life sciences, com-
puter science, and applied mathematics.
Spearheaded by Ed Lightfoot and Sang Kim, the AIChE

SCargill-Dow Polymers, 15305 Minnetonka Blvd., Minnetonka,
MN 55345
2 Chemical Engineering Department, Massachusetts Institute of
Technology, Cambridge, MA 02139
3 Chemical Engineering Department, The Johns Hopkins
University, Baltimore, MD 21218

recently recognized the importance of this emerging field
and established a Topical Conference on Bioinformatics and
Genomics at its annual meeting. With financial support from
Cargill and Parke-Davis, three graduate students working on
problems in various aspects of bioinformatics and genomics
received travel grants to attend the Bioinformatics Topical
Conference held at the AIChE annual meeting in Dallas,
Texas, from October 31 to November 5, 1999. The fellow-
ships were awarded based on a statement of interest submit-
ted by the applicants.
One of the goals of the students' participation was to
provide better exposure to this important new field, to help
them develop their own perspectives and ideas on how un-
dergraduate and graduate chemical engineering education
Vassily Hatzimanlkatls is an Assistant Professor of Chemical Engineer-
ing at Northwestern and he received his Diploma in chemical engineering
in 1991 from the University of Patras in Greece and his PhD in chemical
engineering from the California Institute of Technology in 1996. Prior to
joining the faculty at Northwestern he worked as a Metabolic Engineer at
Cargill Dow LLC. His interests are in computational biotechnology,
bioinformatics and functional genomics.
David Collins obtained a BS and MEng in chemical engineering from
University College London and an MS in Chemical Engineering Practice
from the Massachusetts Institute of Technology. He is currently working
towards a PhD degree in chemical engineering at Massachusetts Institute
of Technology. His interests are in bioinformatics and the management of
and modeling of biological data.
Shawn Lawrence received a BS in chemical engineering from Auburn
University in 1996 and is currently working on his PhD in chemical
engineering at Johns Hopkins University. His research interests include
using bioinformatics techniques to identify novel genes useful for making
therapeutic proteins produced in non-mammalian cell lines more compat-
ible for human use.
Samuel Browning obtained a BS in chemical engineering from Massa-
chusetts Institute of Technology and is currently working toward a PhD
degree in chemical engineering at Cornell University. His interests are in
gene networks and control of the cell cycle.
Kelvin H. Lee is an Assistant Professor of Chemical Engineering at
Cornell University. He received a BSE in chemical engineering from
Princeton University and a MS and PhD in chemical engineering from the
California Institute of Technology. His interests are in the use of mRNA
and protein expression profiles in the engineering of protein secretion and
in the diagnosis of central nervous system diseases.
Copyright ChE Division of ASEE 2000

Chemical Engineering Education

I II c, ,~-I C i ~s

U 7-- 77 77- .7 5
-Is- r=-- ~ c-~-r-~rs -- -. -,- -

could be enhanced to better prepare chemical engineers for
these challenges. This article is one mechanism to communi-
cate these ideas and perspectives, and we hope that it will
serve as a reference for chemical engineer-
ing education development within the con-
text of the rapidly evolving field of Bioinf
Bioinformatics encompasses many di- philo
verse, rapidly developing disciplines, and and the
as a result it has been difficult to describe, engine
One possible definition is the inference of
biological principles and facts from experi- Opp
mentally derived data sets, which are often a signific
large and complex. The ability to draw such both by
inferences requires many of the same skills area
taught in the traditional chemical engineer- bioci
ing curriculum, including process synthe- engineer
sis, design, and modeling. worj
Chemical engineers have made signifi- collabol
cant progress in developing different mod-
eling approaches to biochemical pathways.
These models, which are often initially based life s
on experimentally derived information, serve comput
several important roles. They help organize and
disparate information into a coherent whole, math
encourage logical thought about which com-
ponents and interactions are essential to a
complex system, and make corrections to
conventional wisdom.J' Among the more valuable tools that
have been successfully applied by chemical engineers to the
study of biological systems are nonlinear dynamics, optimi-
zation, and first-principles modeling.
One area in which chemical engineers have not made
equally significant contributions is in the application of math-
ematics and statistics to discovery and refinement of large
sets of raw data, such as those obtained from large-scale
DNA sequencing or mRNA expression profiling studies.
Indeed, this area, which includes the development of tech-
niques for visualization of data sets, clustering analysis, and
other computational and statistical techniques, is an extremely
active area of bioinformatics among computer scientists and
physicists. An important question for the community is
whether chemical engineers have an appropriate skill set to
tackle these new problems.
One feature that distinguishes the chemical engineer from
the molecular biologist or geneticist is the "engineering ap-
proach" to problem solving. The engineer is prepared to
accept incomplete knowledge about a system, asking those

er h



er s

Fall 2000

questions that are necessary to complete the task and not
dwelling on details that are less critical. This approach is
highly appropriate for problems in biological research, where
many details are unknown and many of the
observations are qualitative. But, chemical
atics engineers have to be effective in communi-
S eating their unique approach to the biological
Problems when interacting with the biolo-
roaches, gists. This is one of the challenges for under-
s, and graduate and graduate chemical engineering
uies, education, and it is essential in an environ-
)mical ment where interdisciplinary collaborations
are required in both academic and industrial
los an
to make
impact So, how might we better train undergradu-
Sates to work at the interface of modem biol-
king in ogy and chemical engineering science? In
thin the near term, perhaps with little change and
ical only minor tweaking (of course, this new
and by field is only now developing, and these com-
in ments may only be applicable in the short
W with term). The core training in chemical engi-
neering is highly applicable to many prob-
romie lems of a biological nature. The combination
ices, of skills in mathematics and engineering that
science, most undergraduates are exposed to can be
lied applied to biological problems. Given what
[fcs. appears to be an increase in student interest
in biological problems during recent years,
the curriculum could be infused with more
examples of biological relevance in place of
more traditional examples, as well as examples of systems
analysis applied to a variety of problems.
One area of the undergraduate curriculum that could be
particularly enhanced is in the undergraduate laboratory ex-
perience. The traditional laboratory course has been tied to
unit operations; future adaptations could include a compo-
nent on the scientific method to help students understand
how one selects an appropriate experimental technique to
answer a specific question or how one designs an experi-
ment to obtain high-quality data. These skills will not only
help students perform their own experimental designs, but
will also help them interpret data and communicate with
scientists from other disciplines.

Many of the current research activities in bioinformatics
and genomics are based on parts of the core chemical engi-
neering curriculum. One of the sessions at the AIChE Topi-
cal Conference provided a special opportunity to learn about
different approaches to bioinformatics and genomics as taken

by experts outside the field of chemical engineering. Profes-
sor Ruedi Aebersold (Department of Molecular Biotechnol-
ogy, University of Washington) presented the development
of protein analytical technology for the study of biological
pathways; Professor Gary Stormo (Department of Genetics,
Washington University) discussed his computational and
biophysical approaches for the identification and study of
genetic regulation; and Professor Michael Savageau (De-
partment of Microbiology and Immunology, University of
Michigan) presented the application of mathematical model-
ing for the analysis of complex cellular phenotypes and
molecular processes.
A second session at the Topical Conference provided an
opportunity to learn about different problems within the
realm of bioinformatics and genomics that are currently
being studied by the chemical engineering community. The
following represent a few of these problems and their rela-
tionship to chemical engineering.
John Rogers, a chemical engineer at Parke-Davis
Pharmaceutical Research, has developed a software
tool that maps changes in mRNA or protein expression
levels to corresponding biochemical pathways. This
link provides an opportunity for a scientist or engineer
to quickly move from discovery-based science to
engineering opportunities. The software enables one to
more quickly identify the regulatory and functional
relationship between different enzymes and cellular
pathways. An analysis of the regulatory control
structure governing a particular biological process has
been one of the hallmarks of metabolic engineering.
Andrea Chow, Caliper Technologies, discussed the
development of Lab-On-A-Chip devices that perform
unit operations on a small scale. The development of
such technology requires a detailed understanding of
separations and of fluid transport.
Rob Davis, University of Colorado, described the
optimization of batch reactor schemes to produce RNA
more efficiently.
Chris Floudas, Princeton University, discussed
computational methods for predicting protein folding.
These methods, based on thermodynamics and optimi-
zation techniques, provide an opportunity to identify
drug targets and to perform de novo protein design.
Bernhard Palsson, University of California San
Diego, described the use of thermodynamic, transport,
and kinetic limitations in modeling metabolic func-
tions. Using mass and energy balances for metabolic
reactions catalyzed by proteins with predicted func-
tions, Palsson's group has created a model for the entire
known metabolism of Escherichia coli. This model

allows the prediction of a "phenotypic phase space," a
mutlidimensional space that includes all possible
metabolic fluxes of an organism with a given set of
metabolic pathways. This effort highlights some of the
challenges that the engineer will face in the Genomic
Era. The model lacks kinetic data because detailed
kinetic information on the various enzymes and
pathways does not exist. One of the key features of
biological systems that challenges bioinformaticists is
the"emergent properties" of biochemical networks.
Simply, these are nonobvious properties that can arise
out of a system of biochemical interactions, such as the
integration of signals across multiple time-scales or the
generation of distinct outputs, depending on input
strength or duration. The ability to predict such
emergent properties, using mathematical descriptions
of biological processes, will likely come from a
coupling between modeling the detailed interactions of
molecules and a broader systems-level approach.
George Stephanopoulos, Massachusetts Institute of
Technology, noted that while systems analysis provides
methods for understanding complex systems, one needs
creative formulations of the problems to apply them.
And one needs good experimental data. The techniques
used to collect information about the entire genome
will be only as powerful as the tools available to
analyze it[2] and to use it with some predictive power.
To fuel this type of creativity in defining and solving
problems, a multidisciplinary understanding of critical
experimental technology and theory is critical.
Michael Shuler, Cornell University, made an interest-
ing suggestion to promote successful collaboration
between chemical engineers and biologists. He noted
that each member of a team should be prepared to
perform more than 50% of the effort required to finish
the project.

One of the unique features of the chemical engineering
field is our common "language." Our profession has been
able to work on very different problems and over signifi-
cantly different length scales, with most of the problems
being distilled into the language of chemical engineering.
Unlike other engineering disciplines where individuals may
be defined by the application, chemical engineering is largely
defined by the core training in thermodynamics, transport
phenomena, chemical reaction kinetics, and mathematics,
and is largely independent of the application. 3' The chemical
engineer has an expectation that a process control expert can
understand the essence of a seminar in biochemical engi-
neering or that a person with an emphasis in polymer rheol-

Chemical Engineering Education

ogy can understand a seminar in microfluidics. Similarly,
most chemical engineers expect that they can teach any
course in the undergraduate core curriculum-a feature that
is not true of other engineering disciplines.
A burden that is placed on the graduate student who is
interested in applying chemical engineering skills to the
study of problems in bioinformatics and genomics is the
need to learn the "life science vocabulary" in addition to the
chemical engineering vocabulary-a burden that can add
significant time and course requirements to the graduate
experience. While the feature of a common language in our
profession is a strength that brings us together, it also makes
it difficult to think about changing the core curriculum in
any significant way. We should take care to maintain our
language and ties across the various research topics. At the
same time, we should increase the awareness of students and
educators about similar emerging areas that bridge scientific
disciplines by creating opportunities and forums such as the
Topical Conference in Dallas, Texas.

The authors would like to thank Cargill, Parke-Davis, and
the AIChE and RANTC for support. SB thanks Michael
Shuler; SL thanks Michael Betenbaugh and acknowledges
an NSF Graduate Research Fellowship NSF DGE-9843635;
DC thanks Paul Barton, Doug Lauffenburger, and Merck
and Company; and KHL acknowledges NSF BES-9874938
and DuPont for support. Additionally, we thank Greg
Stephanopoulos and Sang Tae Kim at Parke-Davis.

1. Bailey, J.E., "Mathematical Modeling and Analysis in Bio-
chemical Engineering: Past Accomplishments and Future
Opportunities," Biotechnology Prog., 14, 8 (1998)
2. Hartwell, L.H., J.J. Hopfield, S. Leibler, and A.W. Murray,
"From Molecular to Modular Cell Biology," Nature, 402,
C47 (1999)
3. These are ideas that were originated by Prof. William
Olbricht, Chemical Engineering Department, Cornell Uni-
versity. J

Guiding Principles for Teaching
Continued from page 345.
to wrestle with understanding concepts.
Knowing the students personally is one of the highlights
of being a teacher. I enjoy learning from them! Students
have a depth that is not always evident just from classroom
interactions. Moreover, knowing the students personally cre-
ates a rapport that allows us to joke with each other and to
feel more at ease. When I know the students, I can also
identify those students who are enthusiastic and who are
positive role models, and I can encourage them to help set a
positive tone in the classroom.
My department chair was enthusiastic in encouraging me
to pursue different ideas in the classroom when I first began
teaching. I sensed that he did not think of me as I was at that
particular time, but instead saw my potential for becoming a
good teacher. His attitude made a real impact on me, and I
have embraced it in my own interactions with students. I
respect them and keep in mind that none of us has yet arrived
at our destination-that we are all still part of the process of
becoming assets to our society.
I am still involved in the process of becoming a better
teacher. The guiding principles detailed in this essay will
continue to evolve. Learning new things and adapting them
to the classroom keeps teaching fresh and exciting as I
continue my journey as both a learner and a teacher.

I would like to thank the many colleagues and professors
who have shared their teaching experiences, insights, and

ideas with me. I am indebted to my colleagues and friends
from Rose-Hulman Institute of Technology, particularly my
mentors, William Baratuci, Jerry Caskey, and Noel Moore.

Literature Cited
1. Fulghum, R., All I Really Need to Know I Learned in Kin-
dergarten: Uncommon Thoughts on Common Things, Mass
Market Paperback (1993)
2. Hesketh, R., and R. Ybarra (workshop leaders),
"Undergradute Laboratory," ASEE Summer School for
Chemical Engineering Faculty, Snowbird, UT (1997)
3. De Nevers, N., Fluid Mechanics for Chemical Engineering,
2nd ed., McGraw-Hill, New York, NY, p. 218 (1991)
4. "Steps Toward Becoming a Self-Directed Learner," The
Teaching Professor, 10(4), p. 1 (1996)
5. Felder, R.M., "Any Questions?" Chem. Eng. Ed., 26(3), p.
174 (1992)
6. "Survival Kit for New Engineering Educators," ASEE Prism,
p. 30, October (1994)
References on Teaching
7. Davidson, C.I.1, and S.A. Ambrose, The New Professor's
Handbook: A Guide to Teaching and Research in Engineer-
ing and Science, Anker Publishing Company, Inc., Bolton,
MA (1994)
8. Lowman, J., Mastering the Techniques of Teaching, 2nd ed.,
Jossey-Basqs Inc., Publishers, San Francisco, CA (1995)
Workshops on Teaching
9. Wankat, P., "Teaching Workshop for New Faculty," ASEE
Summer School for Chemical Engineering Faculty, Snow-
bird, UT (1997)
10. Davidson, C.I., and S.A. Ambrose, "The NSF Engineering
Education Scholars Workshop: Preparing Engineering Fac-
ulty of the Future," Carnegie-Mellon University, Pittsburgh,
PA (1996) 0

Fall 2000


In the Fundamentals of Microelectronics Processing*

University of Illinois at Chicago Chicago, Illinois 60607

he ability to instantly communicate and exchange
information with anyone at anytime, anywhere in the
world, i.e., the Internet, has helped eliminate many
of the distances that once kept people apart. In this paper,
we focus on the course "Fundamentals and Design of Mi-
croelectronics Processing," which was offered for the first
time on the Web in the spring of 2000. It is the first course
ever to be offered on the Web by the Chemical Engineering
Department at UIC; to our knowledge, this is also the first
chemical engineering (ChE) microelectronics course ever
offered on the Web.
Through this Web-based dual-level ChE course, we will
present and discuss our experiences on the impact the Internet
is having in the field of engineering education. We will also
examine the Internet's potential benefits for learning and
what it means to teach a graduate/aO,"anced undergraduate
engineering course on the Web.

Increasingly more chemical engineers are entering the
field of microelectronic materials and processing, in part
because basic knowledge of this fast-growing field lies in
chemical engineering. Novel ultra-thin dielectric materials,
passivation of silicon and silicon germanium, surface and
gas-phase reaction chemistry in microfabrication techniques,
diffusion of impurities through the films, and process-struc-
ture-function relationships in micro- and nano-electronics
processing are some representative example systems.1['""
Chemical, electrical, and material engineering principles in
the fundamental understanding and design of microelectron-
ics processing are bringing about great changes in integrated
circuits, micro-electro-mechanical systems (MEMS), and
other fields in which data acquisition, computation, or con-
trols are necessary. Several chemical engineering depart-
ments (worldwide) have either offered courses in microelec-

* Found at (http:/

tronic materials and processing or incorporated several ex-
amples and case studies in core curriculum chemical engi-
neering courses.(e.g. [12-141)
In the spring of 1997, UIC started a dual-level class
(offered to graduate and advanced undergraduate students)
titled "Fundamentals and Design of Microelectronics Pro-
cessing." The objective of the course was to provide partici-
pants and students with the basic principles and practical
aspects of the most advanced state of electronics and MEMS
processing. The emphasis of the course was on basic aspects
of thin film growth, substrate doping and passivation, ion
implantation, lithography, and etching coupled with chemi-
cal kinetics, reactor design, thermodynamics, optimization
and other engineering concepts as they apply to fundamental
processes useful for feature sizes down to the order of about
0.01 1 jm. Therefore, the principles and philosophy under-
lying the selection of topics and their ordering focused mainly
on fundamental notions of transport, reaction kinetics, ther-
modynamics, and reactor design, along with process-struc-

Sanjit Singh Dang received Bachelor's and PhD degrees in Chemical
Engineering from Panjab University, Chandigarh, India (Spring 1997)
and University of Illinois at Chicago (Summer 2000), respectively. At
UIC, he worked under Prof. C.G. Takoudis on process-property-struc-
ture-function relationships of ultra-thin silicon oxynitrides in microelec-
tronics, for which he was presented two national-level research awards.
After his PhD completion, he joined Intel Corporation in Santa Clara,
Raymond Matthes is the Director of Engineering Media Services at the
University of Illinois at Chicago. He received his BA in Journalism,
Philosophy in Communications, Radio, Television, and Film with a minor
in Computer Science from Northwestern University. He is responsible
for the development, production, and delivery of multimedia projects on
videotape, CD-ROM, and on the Internet. He also maintains the com-
puter systems for the Master of Engineering MEng Program on the
Internet, for optimal performance of digital media content production and
Christos G. Takoudis is a Professor at UIC. He received his Diploma in
chemical engineering from the National Technical University of Athens,
Greece, and his PhD from the University of Minnesota. His interests are
in the areas of microelectronic materials and processing, heteroepitaxy
in group IV materials, ultra-thin dielectrics, surface chemistry, in-situ
spectroscopies at interfaces, and heterogeneous catalysis.

Copyright ChE Division of ASEE 2000

Chemical Engineering Education

ture-function relationships in electronic materials and
In the Spring semester of 1998, the scope and effective-
ness of this course was substantially enhanced and aug-
mented with the introduction and implementation of two
Web-based semiconductor simulation tools:115-161 ThermoEMP
and TSUPREM-4. Table 1 shows the outline of the Web
course, which consisted of 41 lectures; the number of lec-
tures listed for each heading in the course outline is not
meant to be related, however, to the number of bulleted
subjects below it. Further, in the Course Information section
of the class there are several additional items, including (i)
two lectures introducing those two Web-based simulation
tools along with step-by-step instructions and working ex-
amples, and (ii) extensive external links.

Instead of attending classes in a centralized institution or
location, students can sit in front of a computer monitor

anywhere in the world, viewing, listening, and interacting
with class materials that have been designed for Internet use.
In order to design effective class material for all students, we
needed to take into account a number of different learning
styles: visual, audio, reading and writing, and interactive (ex-
amples are provided at We had
to prepare materials with the different learning styles in mind.
Various components were incorporated into the class ma-
terials so as to mimic and enhance the real live experience of
a classroom. For example, there were extensive audio seg-
ments of the professor lecturing and discussing specific is-
sues and topics in depth in the first Web offering of the
course. In a classroom, when a student has a question, (s)he
raises his(er) hand, immediately attracting the professor's
attention. On the Web, there were also several effective
ways to communicate with the professor, teaching assistant,
and/or classmates. By means of "asynchronous and synchro-
nous" communication tools such as e-mail, bulletin boards
and chat rooms, the students and participants in the class
could maintain contact with the instructor and fellow class-

Outline of the Course on the Web

Introduction (3 Lectures)
Introduction to Microelectronics Processing, Yield
Overview of Electronic Materials
Crystal Growth (4 Lectures)
Fundamentals of Crystal Growth Processes
Energy and Mass Transfer, Modeling
Doping, Design of Crystal Growth Processes
Modeling and Simulation, Examples
Thin Film Deposition (14 Lectures)
Chemical Vapor Deposition (CVD)
Silicon Epitaxy, Thermodynamics
ThermoEMP as a Simulation Tool
(Thermodynamics of Electronic Materials Processing)
A Priori Process Property Relationships
Surface and Gas-Phase Chemical Kinetics
Kinetics and Mass Transfer of Epitaxial Growth
Transport Phenomena, Reactor Design, Modeling
Silicon-Germanium, Silicon Carbide
Metal Organic CVD (MOCVD)
Doping of Epilayers, Autodoping, Diffusion
Three-Dimensional Integration
A Priori Process Property Relationships, Reactor
Analysis and Design, Selective Epitaxial Growth
Three-Dimensional Integration and Microfabrication Examples
Epitaxial Evaluation, Thin Film Characterization,
Physical Vapor Deposition, Molecular Beam Epitaxy
Plasma Assisted/Enhanced CVD (PACVD or PECVD)
Design of Plasma CVD Reactors, Modeling Examples
CVD of Polysilicon, Amorphous Silicon, SiO, and Si3N
Passivation of Electronic Materials (4 Lectures)
Thermal Oxidation of Silicon
Kinetics, Reactor Design, Modeling

TSUPREM-4 as a Simulation Tool
Oxynitridation of Silicon
Kinetics, Reactor Design, Modeling, Simulation, Examples
Degradation and Characterization of Dielectric Thin Films
Redistribution of Impurities during Thermal Oxidation
Ion Implantation (3 Lectures)
Fundamentals, Kinetics
Design and Process Considerations
Analysis and Design of Masking Films for Ion Implantation
Mathematical Modeling Examples
Advanced Lithography (5 Lectures)
Chemistry and Physics of Lithographic Materials
Fundamentals of Surface Preparation
Positive and Negative Resists, Multi-Level Resists
Design and Control of Lithographic Materials
Advanced Lift-off Techniques, Problem Areas Examples
Dry Etching (4 Lectures)
Low-Pressure Discharges, Physical and Chemical Phenomena
Selectivity Feature and Pattern Size Control
Fundamentals of Dry Etching
Design and Process Considerations
Modeling Simulation Examples
Wet Etching (2 Lectures)
Chemistry Physics, Thermodynamic and Kinetic Considerations
Analysis and Design of Wet Etching Processes
Characterization of Etched Substrate Surfaces, Modeling Examples
Design of Experiments (2 Lectures)
How to Use Statistical Techniques, General Factorial Design
Factorial Design at Two Levels, Interaction Effects, Example
Analysis of Data, Minimum Significant Factor and Curvature Effects

Fall 2000

mates. Bulletin boards and e-mail turned out to be the pre-
ferred communication tools.
Text is the easiest material to prepare for computer-based
learning. Text on a computer can be easily improved by
taking advantage, for example, of HyperText Markup Lan-
guage (HTML) and hyperlinks since it could be prepared to
look like a book or a set of slides. Further, any document
already existing in electronic format could be easily trans-
ferred and presented on the Web. In our course, an electronic
set of extensive written notes was included as the core refer-
ence material. This was in no way a substitute for the tradi-
tional textbook(s) and/or other references, however. In fact,
several references and relevant journal articles, as well as other
reading assignments, were used with every 3-5 lectures.
The entire set of electronic notes was created with an
HTML editor. HTML also helped in incorporating rich me-
dia such as photos, drawings, audio, interaction and, more
importantly, hyperlinks. Hyperlinks allowed students to click
on an area of the document and to immediately be trans-
ported to either a previous or a following chapter, to addi-

tional references published worldwide on the Internet, to
bookmarked pages, to an audio explanation by the professor,
to a graphical representation of the problem being discussed,
or to other relevant sites.
We did not have to learn HTML since current text-editors
(Word, etc.) have the capability to translate to HTML. HTML
can be considered as an encoder, a universal container in
which to put information. It is the universal language of the
Web, enabling anybody to see any information of interest
with a simple Web browser, without the use of specialized
tools. Such electronic sets of written notes can be updated
and published on the Web immediately. This is a significant
benefit since current research and development requires that
material be frequently updated. Yet, overall preparation of
the first electronic set of written notes, coupled with photos,
audio, interaction, hyperlinks and drawings, turned out to be
a substantially higher-than-anticipated commitment of time,
effort, and resources. We estimate that the course took about
three times more time and effort in its initial Web prepara-
tion compared to the preparation required for a well-run

Figure 1. Example of an actual Web page of the class; it demonstrates the use of different media.

Chemical Engineering Education

PlgtB~gi~Ei~~A .1.

traditional course. The lead time needed to get this course set
up was about 6-8 months, and financial and personnel re-
sources from the university were critically important and
extremely helpful. Figure 1 shows an actual Web page of
our class that contains lecture material prepared using text
with audio, hyperlinks, and additional explanations.
"Interactive/interaction" refers to learning by doing some-
thing. For engineering classes, using interactive programs to
show various kinds of results is becoming more frequent.
Examples could include the behavior of a chemical plant
(students define the characteristics of the plant and observe
its performance), fabrication of a micro-electro-mechanical
system (students design/define sequential processes and un-
derstand the characteristics and performance of the system
that is created), etc. When such an interactive tool is avail-
able on the Web, it can easily be linked to the class notes for
the students' benefit.
Two effective examples in this course were the simula-
tion tools ThermoEMP and TSUPREM-4.1"5'61 ThermoEMP
(e.g., is a computer
program that calculates the chemical equilibrium composi-
tions of microelectronic materials processing and the ther-
modynamic and transport properties of the equilibrium mix-
ture (formed after reaction); results are generated through a
methodology that minimizes the Gibbs free energy of the
system via a rigorous thermodynamic analysis.["71 The mini-
mum temperature above which oxide-free silicon growth (a
very important requirement in the microelectronics industry)
can take place, oxide-free silicon carbide growth in a variety
of reaction environments, or the effects of dichlorosilane
flow rate and temperature on the selective epitaxial growth
of silicon can, therefore, be effectively studied with
ThermoEMP. A remarkable aspect of these case studies is
that students experience key issues in real-life problems and
have the opportunity to see that solutions can be obtained, in
some cases at least, within a very short period of time with-
out doing any experiments (e.g., from fundamental knowl-
edge-driven simulation tools).1151 TSUPREM-4 (licensed from
Technology Modeling Associates (TMA), Inc.; http:// is a computer program
for simulating the processing steps involved in the manufac-
ture of silicon integrated circuits, discrete devices, and
MEMS;18' in fact, a wide range of processing steps can be
modeled by this program. Several examples demonstrating
the effectiveness of TSUPREM-4 have been presented and
discussed in Ref. 15.

Web-based learning was beneficial for those students
who could not attend classrooms because of personal or
professional commitments, limited financial resources, or

physical limitations. On a whole, all participants in the class,
including the professor/teaching assistant, had something to
learn. The instructors and students received immediate feed-
back. The student responses on the "instructor and course
evaluation" at the end of semester also indicated that Web-
based learning was useful for those students who perhaps
were shy and reluctant to ask questions in public. Another
advantage was accessibility. Instructional material was avail-
able twenty-four hours a day, eliminating conflicts with
one's schedule. Because the instructional material was al-
ways available, learning was self-paced.
From the instructor's point of view, preparation, editing,
and publishing all the material on the Web for the first time
was a huge undertaking that was made possible with the help
of an Internet-expert teaching assistant (Sanjit S. Dang), an
expert multimedia professional (Raymond A. Matthes), and
financial resources from the University of Illinois at Chi-
cago. Our expectation is that once the class material is in
electronic format, it will probably be easier to modify and
keep up-to-date.

Assessing the progress of students in the Web-based course
was similar to the conventional classroom. Each lecture had
a quiz, which was graded electronically by the instructor/
teaching assistant. Although some of the Web management
tools allow one to create simple multiple-choice quizzes that
are automatically graded by the system when the student
submits the quiz, we decided against using multiple-choice
quizzes in our course. While this resulted in substantially
greater effort in preparation and grading, this system of
testing was found to be much more effective and challenging
to the students. However, more sophisticated kinds of as-
sessments could be prepared using, for example, Mallard, a
web-based interactive quizzing tool (http://www.ews.uiuc.
Homework was posted on the Web and had to be returned
electronically to the instructor/teaching assistant. (Home-
work was also accepted in paper format during the Spring of
2000 since the course was on the Web for the first time
then.) Exam assessment might be done electronically, but
with the present technology it was deemed safer to do it the
old-fashioned way-in a classroom. Before each exam, there
was one help session offered in both formats: in the class-
room (extensive version) and on the Web (abbreviated ver-
sion). Overall, in the learning expectations and in the grad-
ing of problems and tests, there was some differentiation
between advanced undergraduates and graduate students tak-
ing this class. All students had to do the same amount of core
work, but undergraduates were not required to do extra work
and case studies.

Fall 2000

A direct comparison of the averages on the mid-semester
and final exams in the Web (Spring 2000) and traditional
formats (Spring 1997, 1998, and 1999) of the course showed
that students taking the course in the Web format scored
about 15% higher than those in the traditional one. In such
comparisons, however, two apparent assumptions have to be
considered: (i) the exams had comparable difficulties, and
(ii) the average caliber and background of the students who
took the course during the last four spring semesters were
the same. While we believe that the former assumption is a
good one, the latter assumption is very difficult to check.

The feedback and written evaluations of the students on
the scope and instruction effectiveness of the two Web-
based semiconductor simulation tools, ThermoEMP and
TSUPREM-4, were overwhelmingly positive: (i) students
strongly agreed that it was easy to figure out how to use the
simulation tools; (ii) they strongly agreed that the overall class
experience was enhanced by the use of the software; (iii) they
strongly agreed that it was convenient to have universal access
to programs via the Web; and (iv) they would like/have liked to
use the simulation tools in other classes too.
The feedback and written evaluations of the students on
the scope and instruction effectiveness of their first ever
Web-based course included several useful points. The stu-
dents were strongly positive about
The convenience of taking a lecture at any time, anyplace, and
at any pace they wished
The effectiveness of learning through the use of several multi-
media approaches
The use of one quiz for each lecture
The availability of hyperlinks to several Web sites of interest
and reference
The help sessions) before each exam
and, perhaps, above all
The half-hour weekly meetings held in the classroom through-
out the semester. (These meetings turned out to be very impor-
tant in the trouble-shooting of many aspects of the implemen-
tation of this Web course.)
The help sessions) before each exam in the classroom
format were offered as extra help during this first year of the
implementation of the course. We anticipate that beginning
next year, the help sessions, if any, will be totally on the
Web. The live-help sessions in the classroom before each
exam, as well as the weekly classroom meetings, were praised
as 'extremely helpful.'
The students had a variety of comments for other aspects
of the Web-based course experience:
It was difficult to 'stay on task,' that is, quite a few students
indicated they would most likely go through the lectures,

quizzes and homework of this course as late as possible,
since they did not have to go to the classroom at certain
times, on specific days.
There were afew difficulties early on, during the implementa-
tion of the course; they were related with the timing and
'error-free' posting of the course material as well as the fact
that this was the first Web-based course for everyone
involved, students and instructors alike.
More ways of student-student and student-instructor
interactions (like increased participation in live chat rooms
among students, live video-conferencing, etc.) could have
been used.

Possible suggestions/solutions to the issues mentioned
above could include enforced deadlines for quizzes, increased
use of chat rooms (in particular, video-conferencing), and
continuous improvements of and additions to the posted
material on the Web. We anticipate implementing such solu-
tions by the time the course is offered in the spring of 2001.
A direct comparison between the scores on the instructor
and course evaluations at the end of each of the last four
spring semesters, 1997-1999, with the traditional format of
the course, and the scores for the 2000 Web presentation,
revealed that the "instructor's overall effectiveness" (one of
the two required items in all evaluations at UIC) was the
same each year, while the "overall quality of the course" (the
other required item in the evaluations) had a slightly higher
score for the Web format. These results should be viewed,
however, in the context that all course evaluation scores
were already close to the highest possible number. Also, the
course had a comparable number of students each time.
Further insight that was gained from our experience on
the shortcomings and how to improve attempts at true 'dis-
tance' education included: (i) the unavailability of effective
means for proctoring tests and exams outside the classroom,
(ii) the substantial benefit from video-conferencing, (iii) a
need for more thinking about minimizing students' tardiness
with the class material (typically up to the time a test or
homework problem set is due), and (iv) a partial lack of
ideas on how to handle students who may be willing to finish
the course material (and everything else) at a fast pace, say,
in 8 weeks instead of 16 weeks.

Financial support provided by the University of Illinois at
Chicago is gratefully acknowledged. Numerous discussions
with Professors Gerry Neudeck and Mark Lundstrom from
the School of Electrical and Computational Engineering at
Purdue University are greatly acknowledged. Also, the help
of Dr. Nirav H. Kapadia and Suma Adabala from that same
School is greatly appreciated. C.G. Takoudis is especially
thankful to Avant! Corporation (TMA, Inc.) for licensing
TSUPREM-4 for classroom use. Finally, we thank all three

Chemical Engineering Education

= '~~:- -.

reviewers for their excellent comments.

1. Middleman, S., and A.K. Hochberg, Process Engineering
Analysis in Semiconductor Device Fabrication, McGraw Hill,
New York, NY (1993)
2. Lee, H.H., Fundamentals of Microelectronics Processing,
McGraw-Hill, New York, NY (1990)
3. Ruska, S.W., Microelectronic Processing, McGraw Hill, New
York, NY (1987)
4. Wolf, S., and R.N. Tauber, Silicon Processing for the VLSI
Era. V. 1 Process Technology, Lattice Press (1986)
5. Sze, S.M., VLSI Technology, McGraw-Hill, New York, NY
6. Ghandi, S.K., VLSI Fabrication Principles, Wiley
Interscience, (1990)
7. Campbell, S.A., The Science and Engineering of Microelec-
tronic Fabrication, Oxford University Press (1996)
8. Madou, M., Fundamentals of Microfabrication, CRC Press
9. Kovacs, G.T.A., Micromachined Transducers Sourcebook,
Mc Graw Hill, New York, NY (1998)
10. Levy, R.A., Microelectronic Materials and Processes, Kluwer
11. Runyan, W.R., and K.E. Bean, Semiconductor Integrated
Circuit Processing Technology, Addison Wesley (1990)
12. Special Section on Electronic Materials Processing, Chem.
Eng. Educ., 24, 26 (1990)

13. Seebauer, E.G., "A Silicon Processing Option Suitable for
Chemical and Electrical Engineers," AIChE http://, Nov. (1998)
14. Parsons, G.N., "Electronic Materials Option, and a Video-
Based Electronic Materials Course in Chemical Engineer-
ing at N.C. State University," AIChE,
Nov. (1998)
15. Dang, S.S., and C.G. Takoudis, "Instruction via Web-Based
Semiconductor Simulation Tools," Chem. Eng. Educ. 32,
242 (1998)
16. Dang, S.S., and C.G. Takoudis, "Chemical Engineering in
Microelectronics," AIChE, Nov. (1998)
17. For example: (a) Gordon, S., and B. J. McBride, Tech. Re-
port SP-273, NASA, NASA Lewis Research Center (1971);
(b) W. H. Gaynor, "Applicability of Thermodynamic Calcu-
lations on the Prediction of Chemical Vapor Deposition Re-
actor Performance and Process-Property Relationships," B.S.
Thesis, School of Chemical Engineering, Purdue University
(1989); (c) Lee I-M., A. Jansons and C.G. Takoudis, Effects
of Water Vapor and Chlorine on the Epitaxial Growth of
SiGe Films by Chemical Vapor Deposition Thermodynamic
Analysis," J. Vac. Sci. Techn. B 15, 880 (1997), and refer-
ences therein; (d) C. Richardson, "Enhancement of the
ThermoEMP Program for Calculation of Complex Chemical
Equilibrium Compositions," NSF-REU Report, Department
of Chemical Engineering, University of Illinois at Chicago
18. TSUPREM-4 User's Manual, Version 6.4, Technology Mod-
eling Associates, Inc. Sunnyvale, CA, October (1996) 0

BOOK REVIEW: Engineering Flow and Heat Exchange
Continuedfrom page 343.

low pressure, "molecular" flows. Here the concept of "mo-
lecular slip" is introduced.
Chapter 5 contains, as mentioned above, concepts and
problems of non-Newtonian flow explained in a direct and
simple-to-understand fashion. The student is reminded that,
in general, this complex fluid can be treated as Newtonian
with an additional term and all that is required is to find the
correction due to the non-Newtonian behavior. Since most
fluids in industrial practice are non-Newtonian, the intro-
duction of this material is, I think, crucial. Furthermore,
rheometry to measure non-Newtonian behavior is also
presented in detail.
The first part of the book, also contains chapters on flow in
porous media and in fluidized beds. They are also well
written, with many examples and actual industrial applica-
tions both solved and presented as homework problems.
The second part of the book, on heat transfer and heat
exchanger design, is also enlightening, crisp, and well con-
structed. Chapters 9, 10, 12, and 13 contain the usual mate-
rial on different forms of heat transfer, combined heat trans-
fer, and two-fluid heat exchanger design. Here again, it is
assumed that the student has taken a previous introductory

course in heat transfer since familiarity with, for example,
the Nuselt number is required. The material in Chapters 11,
14, and 15 contains unsteady heating and cooling and design
of direct-contact exchangers and regenerators-material usu-
ally not covered in standard texts. The second part ends
(Chapter 16) with a set of recommended problems involving
material contained in the book, keeping in mind practical,
industrially relevant applications.

There is an extended Appendix with very useful informa-
tion such as transformation of units, some material proper-
ties, dimensionless groups, and values of more important
parameters such as heat transfer coefficients in different
geometries. The text also comes (available to the instructor)
with a set of solutions to the problems in each chapter with
every second problem being solved. The problems in the last
chapter (16) all have solutions. The illustrations in the book
are inspired and clear, while the nomograms, mostly for heat
transfer calculations, are up-to-date and easy to use.

Over all, this is an excellent book, written with the heart.
The reader can visibly appreciate this. It should be a perma-
nent fixture on the bookshelf of any engineer who studied or
uses fluid flow and heat transfer in his work. 1

Fall 2000

e, W -curriculum


A Tool for Enhancing Excellence in ChE Students

Rice University Houston, TX 77005

his article is a brief description of efforts made in the
Honors in the Major Program in the College of Engi-
neering (jointly operated by Florida A&M Univer-
sity and Florida State University) at Tallahassee, Florida, to
enhance excellence in the education of its most capable
chemical engineering students. The program is an effective
tool in attracting and retaining this important pool of stu-
dents.1" The Honors in the Major in chemical engineering is
a thriving program that produces a relatively large number
of highly qualified engineers. Most of our Honors graduates
continue their careers in graduate school at universities across
the country and perform particularly well. Others who de-
cide to immediately enter the work force find success in
positions with responsibility levels usually reserved for more
experienced engineers.
The program has gained a reputation for producing reli-
able professionals. Some of the companies that have hired
Honors students have returned to hire additional Honors
students, sometimes from the same research group. "Word
of mouth" is a great way to advertise, and as the students (as
well as the recruiters) discuss their experiences with others,
the more motivated high school students and entering col-
lege freshmen gain a greater interest in our program. Having
earned a reputation for producing well-qualified engineers,
we are successful in attracting (and retaining) students who
previously would have opted to attend other universities
with more traditional chemical engineering programs.
Prior to establishing the Honors in the Major Program as a
viable option for engineering students, many of the more
capable students found the classwork challenging to them
only at an average level. Although an Honors program was
available to the students, they considered its level and type
of work less than what they were looking for (i.e., too time
consuming, too broad in scope, marginal work, not more

Address: Florida State University, 2525 Pottsdamer Street,
Tallahassee FL 32310

challenging). Therefore, the task for the College of Engi-
neering and the Chemical Engineering Department was to
make the program an appealing option to students and then
to find candidates whose excellence would work as a "mag-
net" for new candidates.
After internally addressing the issues regarding the poor
participation in the program, it was newly advertised in such
a way that talented students now found it a feasible and
attractive opportunity. The option presented to the students
was to allow them to apply the Honors in the Major project
(provided they successfully completed all requisites) to cur-
riculum requirements in lieu of two technical electives (a
total of six credit hours). Those who did not satisfy the
requisites for the Honors Program would still be required to
take the technical electives in order to satisfy graduation
requirements. This approach worked very well.
In the following sections, the reader will find descriptions
of several important aspects of the program. They include an
overview of the program, a description of the different as-
pects (such as candidate requisites and time management),
characteristics of research projects suitable for the program

Sharon G. Sauer has a BS degree in Chemi-
cal Engineering (with Honors in the Major)
from Florida State University and is currently
a PhD candidate under the direction of
Profesor Walter Chapman, an NSF Fellow,
and Robert A. Welch, Foundation Fellow at
Rice University. Before joining Rice, she
worked as an engineer for three years at Shell
in Houston TXY I

Pedro Arce is Associate Professor and a Fac-
ulty Associate of the Geophysical Fluid Dynam-
ics Institute and of the Material Research Pro-
gram at Florida State University. He has a
Diploma in Chemical Engineering from the
Universidad Nacional del Literal (1977), and a
Ms.Sci(1987) and a PhD (1990), both in Chemi-
cal Engineering, from Purdue University.

Copyright ChE Division of ASEE 2000

Chemical Engineering Education

(along with some examples), an approach for working with Honors
students, and some concluding remarks.

In this section, the major characteristics of the program are noted
and some of the differences with respect to the path taken by the
regular students are presented. Key program aspects involve the
application process, selection of a research topic and an Honors
Professor, the assignation of the Honors Professor, formation of a
thesis committee, writing of a research prospectus, the midterm re-
port, and the writing and defense of a thesis. The Honors and Scholar
Office at Florida State University establishes the general guidelines
for the program, including setting deadlines and the specific require-
ments for thesis format and thesis archives (Florida A&M has a
separate procedure).
In Table 1 the basic characteristics of the regular path are com-
pared/contrasted with those of the Honors in the Major program. One
of the most notable differences in the programs is the type of student
who pursues the individual programs. For example, students in the
regular program have a strong desire to finish quickly and join the
work force as soon as possible. In contrast, students pursuing the
Honors path have a strong desire to excel, an established ability to
learn independently, and in general, a track record of focused perfor-
mance. The level of independence required in the Honors Program is
also significantly higher than for students on the regular path. Fur-
thermore, the Honors Program provides opportunities not available
to those in the regular path, such as the possibility of participating in
presentations at technical meetings and, in the most productive cases,
refereed journal publications.


In Table 2 we present an outline of the major aspects involved in
the Honors in the Major Program, including the candidate requisites
and time management on which we would like to elaborate. Although
there are many ways to communicate the requirements to the candi-
date, one of the most effective ways is for the departmental "Honors
Program Director" to personally interview the candidate. The pro-
gram director has the opportunity to present the requirements in
detail and to ascertain the student's level of interest. This meeting
also allows candidates to ask clarifying questions and, specifi-
cally, to mention anything that they feel is pertinent to their
unique situation. In order for the program director to successfully

Outline of the Program

Introduction of the Program
Sophomores, First-Semester Juniors, Juniors
Role of research in undergraduate education
Invitation and general announcement of the program
Meeting with the departmental program director
Candidate Requisites
Minimum GPA (3.2/4.0)
Independent thinker
Enjoy looking at a given problem from variety of points
of view
Strong organization skills
Self-motivated, requiring minimal supervision
Selection Process
Academic record
Written statement of purpose
Prior activities (e.g., science fairs)
Level of interest/personal motivation
Joint faculty/program director evaluation
Research Prospectus and Thesis Committee
Thesis Committee
Tenured or tenure-track
The Honors Professor
Second professor from the department
External member (i.e., from another department)
Assist the student in directing the project
Proper crediting of work
Purpose and structure of a prospectus
Selects committee members in conjunction with
Honors Professor
Takes ownership of the project by formulating the
Time Management and Progress Evaluation
Tentative schedule
Milestones and target dates
Weekly (or more frequent) meeting with advising
Regular (but flexible) schedule for research work
Mid-term report
Presentation of report to committee
Final draft of thesis
Oral defense of thesis
Technical meeting presentation (Optional)
Journal publication (Optional)

Fall 2000

Comparison of Programs

Regular Path Honors Program
Qualification University entrance Minimum GPA (3.2/4.0)
Focus Structured and repetitive classroom work Unstructured individual research
Driving force Faculty and other students Student
Student goal Finish Excellence
Additional requirement Write/defend thesis
Possible by-products Technical meeting presentation, publications

fill the role, he must have a thorough knowledge of the
various aspects of the program and have previously served
as an effective Honors Professor.
One of the first things communicated to candidates is the
fact that the Honors Program is not for everyone. The activi-
ties within the research project are demanding and require a

strong commitment on the student's part
successful. In addition, university policy
does not allow financial compensation for
doing honors work! (This does not ex-
clude standard financial aid packages.)
This is, sometimes, an important aspect
for the candidate. Furthermore, the stu-
dent is usually reminded that while the
minimum GPA is a necessary require-
ment, other more personal attributes (such
as organizational skills) are often enor-
mously beneficial. Also, personal moti-
vation is one of the strongest determi-
nants for success. A careful explanation
and understanding of all these character-
istics will help avoid "false" expectations
on the part of the candidate. A thorough
evaluation of the student's potential suc-
cess is necessary to ensure maximum re-
tention in the program.
Furthermore, in order for the project to
be successful, the student must have a
sense of project ownership. It is essential
that the writing of the prospectus in which
the major goals of the project are stated is
the result of the student's effort and moti-
vation. A "research contract" written by
the professor is clearly an unacceptable
approach to this document.

order to be

Since students are typically very busy with course work
and extracurricular activities, a tentative schedule with mile-
stones and target dates is a vital tool for assisting them to
progress in a timely manner with their Honors work. The
most efficient students ordinarily make a schedule for them-
selves to help with organization and time management.
Weekly meetings between the Honors Professor and the
student are essential to ensure the student's development as
an effective researcher. These meetings give the student
ample opportunity to ask for input, to update the advising
professor on the project's status, to refine the project as
needed, etc. During this early stage of a student's develop-
ment as a researcher, it is imperative that the professor
closely monitor the progress to prevent the development of
poor habits and misconceptions regarding the manner in
which research is conducted. This includes not only time
management and the other aspects previously discussed,
but also the moral obligations to be honest and to main-

tain a high standard of integrity in the reporting of data
and other results.
One of the most useful "milestones" in the course of the
Honors project is writing a midterm report. It serves both the
student and the Honors Professor well in not only reviewing
the accomplishments that the student has made but also in
clearly defining the remaining activities necessary for the
project's successful completion. To some
extent, this midterm report can be viewed
as the "proposal to defend" counterpart of
m has the doctoral candidate, albeit within a
station much reduced scope. The presentation of
reliable this report to the thesis committee for feed-
s. Some back is strongly recommended; it allows
at have for enhanced communication between the
students student and the committee in that all points
d to hire of concern can be readily addressed and
donors provides the student with an opportunity
to demonstrate a sound understanding of
retimes the project goals.
Depending on the status of the project
op ... at this juncture, the committee can either
ssful in assist the student in finalizing plans for
(and the project's completion in time for gradu-
udents ation or it can recommend termination of
ly would the project. If the later recommendation is
Attend made, the student is encouraged to enroll
ties with in regular electives in order to graduate at
tional his/her scheduled time. In these rare situ-
ineering nations, the primary reason for terminating
s. a project has been a lack of student com-
mitment and/or a misunderstanding of the
level of involvement required for success-
ful completion of the project. This point

illustrates the importance of instructing the student, prior to
entrance into the program, regarding the intense level of
dedication and self-motivation needed to successfully com-
plete an Honors project.

One of the central aspects on which success of an Honors
in the Major Program depends is the type of research project
selected. In general, the project must be: a) independent of
other students' projects, in particular from work performed
by graduate students for their thesis requirements; b) of a
scope that allows the student to achieve some important
goals while completing the project in two (or at most, three)
semesters; and c) in an environment conducive to building a
solid basis for future involvement in research. It is crucial
that the project definition be as precise as possible since it
can have significant effects on the student's progress (i.e., a
loosely defined project breeds confusion and an open door to
many directions, while a tightly defined project provides a

Chemical Engineering Education

The program
gained a rep
for producing
companies th
hired Honors
have returned
students, son
from the s
research gr
we are succe
retaining) st
who previously
have opted t(
other universe
more tradi
chemical eng.

Selected Honors in the Major Theses
(Year of Graduation, Honors Professor,
and Current Affiliation of the Student in Parentheses)

"Study of Parameter of Diatomic Oxygen in Sulfuric Acid/Methanol
Mixture," Terry M. Ake (1997, Dr. E. Kalu, University of Florida)
"Development of Computer Batch Reactorfor Solution Polymeriza-
tion," Brian Bennet (1998, Dr. S. Palanki, Private Industry)
"Micro-dynamics of Blood Particles in an Arterial Stenosis
Domain: An Analysis in Terms of Blood Flow Regimes and Particle
Trajectories, Tiffany Cloud (1998, Dr. P. Arce, University of
"Convective-Diffusive Transport in Arterial Stenosis Using
Lubrication and Area Averaging Methods," Marc Homer (1994, Dr.
P. Arce, Northwestern University)
"Drop Breakup in Mini-Hydrocyclones," William Martin, IV (1998,
Dr. D. Wesson, Private Industry)
"Effect of Particle Deformation in Stokes Flows, Jay Norman
(1998, Dr. P. Arce, University of Texas)
"Application of Electro-Settling to Water Clarification: An
Experimental Investigation, Chelsey Phillips (1998, Dr. P. Arce,
Private Industry)
"Solute Transport Under the Influence of Two Orthogonal Electric
Fields in Laminar Flow: An Area Averaging Approach," Sharon G.
Sauer (1993, Dr. P. Arce, Rice University)
"Development of Stratum Corneun Experimental Models to Study
the Physical Properties of the Skin, Cherri Stabler (1998, Dr. B.R.
Locke, Georgia Institute of Technology)
"Radon Transport in House Crawl Spaces, Derek Sturgis (1997,
Dr. J. Telotte, Private Industry)
"Convective-Diffusion and Reaction in Thrombosis, Sonia Walker
(1997, Dr. P. Arce, University of Florida)

clear pathway). Honors students must realize that organiza-
tion is important for achieving success, but it must be a
dynamic organization with flexibility to add new develop-
ments. In any event, the student's formulation of the activi-
ties needed to successfully complete the project is one of the
first and most important aspects in the development of a
potential researcher and it must not be overlooked.
The Honors program in our department has used projects
of an analytical, computational, and experimental nature.
Table 3 lists a sample of the different projects completed in
our department in the past few years. In some cases, the
candidate is the one who provided the project idea. Two of
the examples (the project on arterial stenosis by Marc Homer
and the project on electro-settling by Chelsey Phillips) be-
long in this category. Some of them involve fairly advanced
techniques that are not covered in the regular curriculum
courses. For example, Marc Horner's project involved
the use of lubrication approximation methods"12 in con-
junction with volume averaging methods1[3, and the work
by Tiffany Cloud involved the use of concepts from

In order for a project to be successful, it need not involve
"flashy" machines where, frequently, the Honors student
becomes a mere spectator of graduate and/or postdoctoral
student performances or (even less desirable) they simply
become assistants to graduate students. In sports, for ex-
ample, Brazil has an outstanding soccer team where many
prestigious players have learned, developed, and perfected
their skills playing with grapefruit "soccer balls" on the
streets of their home towns. Whether the soccer ball was
made from paper or rolled-up socks filled with old pieces of
clothes, it is the practice, the innovation, and the determina-
tion that formed these players long before they possessed a
"real" soccer ball. It is these same individual characteristics
that develop a student into a researcher.

Table 3 lists several examples of successful Honors projects.
Here we briefly describe one of the projects that achieved an
extraordinary level of accomplishment. The topic was cen-
tered on the use of fluid mechanics concepts coupled with
transport theory, specifically electro-convective diffusive
transport in porous beds.151 This work was an effort to show
the effect of orthogonal and parallel electrical fields on the
dispersion and convection of material in channels and in-
volved the use of averaging techniques in convective-diffu-
sive transport with applications to electrophoresis. To com-
plete the project successfully required learning volume aver-
aging techniques'3' and the formulation of conservation equa-
tions with applied electrical fields.161 Neither topic is nor-
mally covered in the regular curriculum. This work resulted
in a presentation at an AIChE annual meeting,'71 in a refereed
publication,'"8 and in a proceeding publication.[9]
The efforts of several of the students[5'0-121 have been key
in initiating an "evolutionary type" of analysis of the topics
covered, which are currently in various stages of research.
Also, each of the students was able to produce either a
proceeding or a peer-reviewed publication, which is indica-
tive of the high degree of accomplishment achieved by these
students. Each student has continued to use the research and
organizational skills developed during the Honors work.
Several have indicated that having learned the basics of
research methodology and the interaction with an Honors
Professor as an undergraduate has proved invaluable in pro-
viding them with a sound basis for their graduate research.
The time and project managements skills and independence
that they developed in their Honors work has also been
beneficial in their industrial positions.

Honors in the Major students are highly talented individu-
als who generally have a great desire to learn but often

Fall 2000

display low confidence in their abilities. Although, due to
their prior accomplishments, they know that they are ca-
pable of doing very complex and difficult tasks, they exhibit
self-doubt. Typically, they are very critical of their accom-
plishments and are inclined to ignore (or perhaps are not
even cognitive of) the level of skill that they have already
mastered in their high school and university courses and
activities. Consequently, they need considerable support,
encouragement, and coaching by their advisor in guiding
them to successful completion of a project. The professor
must foster a caring environment that allows the students to
laugh about mistakes and to learn from them.
Honors students characteristically pay little attention to
the credit that should be given to their work, ideas, and/or
results. This is an important aspect that sometimes is over-
looked. For example, when an Honors student works with a
graduate student who, in his/her thesis, subsequently uses
the results and ideas that the Honors students produced or
helped to produce, the one line thanking the Honors student
in the acknowledgment section seems minuscule; it may not
give sufficient credit to the level of contributions by the
Honors student. This demonstrates the importance of the
Honors project's independence, which is crucial in order to
avoid a misconception on the part of the Honors students as
to the role played by their project and the recognition that
should be given to it. As such, the importance and meth-
ods of crediting work, ideas, and results should be among
the topics discussed with an Honors student at the begin-
ning of the project, preferably in the initial meeting with
the committee.
In order to be successful in leading Honors students to
successful completion of their projects, the advising profes-
sor must be able to handle a flexible schedule of meetings
and to be aware of the time commitment that must be made
to ensure the students' success. It is also important that the
professor have the ability to recognize when the student/
project match is not working to its fullest potential (and then
to adjust the project topic accordingly) as well as to accept
that the only "final product" may be the student's develop-
ment as a future researcher.
Since students typically have a hectic schedule encom-
passing a wide range of activities, the Honors professor must
be open to accommodating the student's time constraints in
scheduling meetings that will allow the student to produce
meaningful (even if they are partial) results. In addition,
close monitoring of the student's progress in the regular
courses is important to ensure that they are getting the full
benefit of their undergraduate educational. Many of them
tend to play down the course work due in part to some of the
reasons listed in Table 1 (e.g., repetitiveness of the tasks).
Nonetheless, the Honors professor can do a great service to
his advisee by conveying the relevance of the coursework to
the student's future (e.g., to qualify for national scholarships

for graduate school or in the job search).
The complex and vital interaction between the Honors
student and the Honors professor suggests that the use of
graduate students and/or postdoctoral fellows must be
avoided, or at least redefined. Graduate students can be very
useful in the Honors program (and vice versa), but their role
must be limited to helping the undergraduate student learn
new techniques, set up experimental devices. etc. They must
not consider the Honors student as merely additional help
for their own projects. The graduate student needs to be
aware that his or her role is a "service to" rather than "a user
of' the Honors program. Interaction and mutual help is
always beneficial to both students; nevertheless, "one-sided"
performance does not support development of the Honors
student as a researcher.
The activities related to the program potentially afford the
graduate student an excellent opportunity to become in-
volved in the art of coaching and guiding a student to comple-
tion of a research project. From this point of view, the
graduate student can benefit enormously, especially those
who have an interest in academic positions after their doc-
toral graduation. A similar outlook applies to any postdoctoral
students in the group.
The use of technical meeting presentations is, in general,
very beneficial for the enhancement of student productivity
as well as for the direction and timetable of the project. It
also provides an excellent opportunity for the candidate to
learn how to communicate scientific results to a highly spe-
cialized audience. The students must be able to present and
defend their results in front of an audience without the help
of the professor in order to make the experience meaningful.
Practice that includes comprehensive questioning will help
ensure that the students are well prepared to answer ques-
tions, just as if they were defending their thesis for final
graduation. With practice and coaching by the advisor prior
to the technical meeting, both student and advisor can gain
confidence in the student's preparedness. Our program has
used these presentations effectively to make the projects
even more invigorating for a number of students. Several
students who took advantage of these presentations were
very successful in interacting with these high-level audi-
ences, and a number of them have received "best presenter"
awards in regional and/or national competitions.
Only in the most productive cases will a student be able to
write an article for publication submission. While it would
be superb if this aspect could be included in the overall
project, only the most tenacious students (and depending in
part on the specific project) are able to finalize the full round
of tasks to be achieved. As such, this should not be viewed
as the primary goal of the Honors project. At a minimum,
most successful projects are able to establish important
groundwork for future research. For example, many of
our projects have been useful as support in the submis-

Chemical Engineering Education


sion of a research proposal and/or in better defining the
targets of a doctoral dissertation.

The Honors program has a number of advantages for the
student as well as for the department housing the students.
Students from our program typically receive job offers long
before their graduation date, with salary offers considerably
higher than those for graduates from the regular path. The
students who do decide to enter the work force immediately
after graduation frequently advance quickly through the
ranks to positions most often reserved for more experi-
enced engineers. When the opportunity presents itself,
they are typically able to change positions to other com-
panies with relative ease.
The Honors students who decide to continue their educa-
tion in graduate school are also quite successful. Some of the
graduate programs that have accepted our students include
Georgia Tech, University of Florida, North Carolina State
University, Northwestern University, Rice University, and
the University of Texas-Austin. The feedback we receive
from these students indicates that our Honors Program has
prepared them well for graduate work.
During the period from 1994 to 1998, the Honors Program
has reached an all-time high in student enrollment, with a
maximum of eight to ten students in residence working with
six to eight different professors. Both the department and the
college benefit from the program since many top students
opt to remain in the department, and through the years these
students have subsequently acted as magnets in attracting
other talented students. Also, the regular curriculum classes
have a group of students that introduce a steeper grading of
knowledge, which often provides a greater exchange of
knowledge among the students.
Some administrative improvements have also been real-
ized in the last few years. For example, for quite a while the
department did not recognize the Honors in the Major stu-
dents as part of the teaching load, in spite of the fact that the
students required considerable attention, involvement, and
time. There is now a percentage of dedication assigned in a
manner similar to the allocation of effort for graduate stu-
dents. Nonetheless, to realize the full benefit and potential of
the program, it needs an even wider diffusion and higher
recognition within our college and university.
The Honors in the Major program is definitely a success-
ful tool for attracting and retaining some of the best and most
promising students in the department. Numerous students
have indicated that one of the primary reasons they stayed in
the chemical engineering program was the availability of the
Honors in the Major option. Indeed, this program is profi-
cient in producing high-quality undergraduates who are flour-
ishing either in graduate school or in professional life. Some

Fall 2000

of the key factors that play a part in the program's success
are the careful selection of the students, matching between
candidate and Honors professor, and the commitment and
dedication of faculty involved in the direction of the stu-
dents. Moreover, fostering a respectful environment and car-
ing attitude towards the students participating in research
has promoted a positive effect in attracting new candidates.

We would like to thank Dr. Bruce R. Bickley, Jr. (former
Director of the Honors and Scholar Office at Florida State
University) and his personnel for support and encourage-
ment and to Mr. W. C. Finney (Director of the Graduate
Laboratories at the Department of Chemical Engineering at
FAMU-FSU) for his help and commitment to a number of
Honors students. The authors are also indebted to Professor
Robert L. Sauer for his comments on improving the manu-
script. This article is based partially on a contribution to the
Division of Chemical Engineering Education, ASEE, An-
nual Meeting, Charlotte, NC., June 20-23, 1999.

1. Arce, P., "Role of the Honors Program in the Attraction and
Retention of the Brightest and the Best CHEME Students,"
Proc. ofAnn. Meet., ASEE, Charlotte, NC, June (1999)
2. Denn, M., Process Fluid Mechanics, Prentice Hall, Englewood
Cliffs, NJ (1981)
3. Whitaker, S., The Method of Volume Averaging, Kluwers
International Publishers, Holland (1999)
4. Kim, S., and S. Karrilla, Microhydrodynamics, Butterworth-
Heinemann, Boston, MA (1989)
5. Sauer, Sharon, "Solute Transport Under the Influence of
Two Orthogonal Electrical Fields in Laminar Flow Regime:
An Area Averaging Approach," Honors in the Major Thesis,
Florida State University, Tallahassee, FL (1993)
6. Newman, J.S., Electrochemical Systems, 2nd ed., Prentice-
Hall, Englewood Cliffs, NJ (1991)
7. Sauer, S., P. Arce, and B.R. Locke, "Solute Transport Under
the Influence of Two Orthogonal Electrical Fields in Lami-
nar Flow Regime: An Area Averaging Approach," AIChE
Annual Meeting, St. Louis, MO (1993)
8. Sauer, S., B.R. Locke, and P. Arce, "Effects of Axial and
Orthogonal Applied Electrical Fields in Poiseuille Flows:
An Area-Averaging Approach," I&E Chem. Res., 34, 886
9. Chen, Z., S. Sauer, and P. Arce, "Dispersion of Fibers in
Shear Flows: An Area-Averaging Approach," Proceed. ofXII
Internat. Cong. ofRheology, 573 (1996)
10. Homer, Marc, "Convective-Diffusive Transport in Arterial
Stenosis Using Lubrication and Area Averaging Methods,"
Honors in the Major Thesis, Florida State University, Talla-
hassee, FL (1994)
11. Phillips, Chelsey, "Application of Electro-Settling to Water
Clarification: An Experimental Investigation," Honors in
the Major Thesis, Florida State University, Tallahassee FL
12. Cloud, Tiffany, "Micro-Dynamics of Blood Particles in an
Arterial Stenosis Domain: An Analysis in Terms of Blood
Flow Regimes and Particle Trajectories," Honors in the
Major Thesis, Florida State University, Tallahassee, FL
(1998) 0




Northwestern University Evanston, IL 60208

Real engineering problems are rarely black and white.
This is particularly true when problems are placed
on the canvas of societal, economical, ethical, envi-
ronmental, and political considerations. There are, however,
few (if any) places in the standard undergraduate curriculum
to discuss and debate complex interconnected issues, explor-
ing the pros and cons of various positions. With that in mind,
a little over four years ago, the Chemical Engineering De-
partment at Northwestern University initiated a novel activ-
ity designed to achieve several differing goals. It is known as
our annual "Chemical Engineering Debates," the fourth of
which was recently held. We have been highly pleased with
the results of this activity and would like to share our experi-
ences with others in the community who may wish to con-
sider similar programs within their own institutions.

The idea for the debate program grew out of concern for
the following issues connected with our undergraduate pro-
An absence of significant discussion on chemical
engineering issues in the context of societal, environ-
mental, and political constraints.
A lack of opportunities for informalfaculty/graduate
student/undergraduate interactions.
A scarcity of intellectual discussion among students
and faculty on issues outside of the classroom or
curricular issues.
The ever-increasing tendency for faculty and students
to narrow their focus to issues of immediate profes-
sional and/or academic interest.
Another concern, perhaps less prominent at the time, was the
need to take some steps to focus attention on awareness of
broad societal issues and on the importance of life-long
learning among our students, as mandated in the then up-

coming ABET EC 2000 expectations.
Consideration of these issues led to the formulation of
plans to initiate a debate-type activity. This was fostered by
a long-standing tradition of excellence in collegiate debate at
Northwestern and the fact that one of the graduating seniors
in the class of 1997 (Ian Smith) was a member of the much-
heralded Northwestern debate team. Specific reasons for
choosing a debate format included the opportunity to put
together mixed teams of students and faculty and to focus on
technically based issues of social significance. Our thoughts,
borne out in subsequent events, were that students and fac-
ulty would be able to work together effectively outside the
classroom and that this type of event would be of significant
interest to other students as well.

Four successful Chemical Engineering Debates have been
held. The general topics, specific questions posed, and the
moderators are listed in Table 1.

Julio M. Ottino is a faculty member in the
Department of Chemical Engineering at North-
western University, where he is Walter P.
Murphy Professor and R.R. McCormick Insti-
tute Professor. He received his PhD from the
University of Minnesota. His research inter-
ests are in the areas of complex systems,
granular materials, and fluid mechanics.

Josh S. Dranoff is Professor of Chemical En-
gineering at Northwestern University, where he
has been since 1958. He received his BE de-
gree from Yale University and his PhD from
Princeton University. His research interests are
in chemical reaction engineering and chromato-
graphic separations.

Copyright ChEDivision ofASEE 2000

Chemical Engineering Education

Debates Held at Northwestern

March 1997
Future Directions for the Petroleum
Industry, Exemplified by Exxon
Should Exxon shift its long-term,
strategic focus away from petroleum
Mr. Jay Hook, Retired Group President,
Masco Corporation; Adjunct Professor
at Northwestern University

March 1998
Sustainable Development: Implications
for the Chemical Industry
Is sustainable development a viable
business strategy for Monsanto
Chemical Company?
Dr. Warren Haug, Retired Vice President
Research & Development, Procter and
Gamble Company; Adjunct Professor
at Northwestern University

May 1999
Policing the Biotechnology Industry
Should knowledgeable scientists and
engineers working in the field of
biotechnology be responsible for
regulating the industry or should a
government body be charged with this
Dr. Edward Hughes, Professor Kellogg
Graduate School of Management,
Health Services Management Program,
Northwestern University

May 2000
Global Warming and Greenhouse Gas
Should the United States seek legally
binding limits on greenhouse gas
emissions for all nations at this time in
order to combat global warming?
Professor William White, Industrial
Engineering and Management
Sciences, Northwestern University;
Retired CEO, Bell and Howell

Fall 2000

Let us now discuss the implementation issues, using the first debate as an


Strong initial faculty effort is essential. But for the activity to be successful in
the long run, continual student leadership is necessary. A team of one under-
graduate and one graduate student seems ideal, although we have had one
instance of two undergraduates serving as organizers. The organizers lead the
recruiting of debaters, frame the topic selection, and take care of publicizing the
event, including preparing flyers with brief bios of the participants for distribu-
tion at the debate itself. Several discussions between the organizers and a
faculty consultant are usually needed to converge on a suitable topic.

General Structure

In setting up the debate structure, we were concerned about the extra burdens
that participation in the debate would impose on both faculty and student team
members. While recognizing that few activities are successful without the
significant effort of some key individuals, we did not want to place unrealistic
and discouraging demands on participants who already had full schedules.
Therefore, some preparatory work on topic selection and digestion of key
background materials by the debate organizers was deemed necessary. We
decided that all participants would be given basic background information two
to three weeks in advance of the debate, but that the specific question to be
debated and the assignment of "pro" and "con" positions would be deferred
until the week before the scheduled debate. Thus, in the 1997 Exxon debates
the positions debated were
Affirmative: Oil is here to stay; oil should remain the strategic focus of
Negative: Oil is on its way out; Exxon should shift its strategic attention
away from oil.


In order to involve as much of the department as possible, we decided that each
of the two debating teams would be composed of six members: two under-
graduates, two graduate students, and two faculty members. All of the partici-
pants were to be volunteers, solicited in each case by a member of the relevant
group. The number is not rigid. More participants increase the chance of people
to participate directly. Six persons per team is probably an upper bound and
requires that everybody adhere to the allotted times. Incidentally, with the
exception of our very first debate, none of the participants (students or faculty)
had prior experience as debaters at the collegiate level. Nonetheless, this did
not appear to diminish their enthusiasm or effectiveness.


The choice of the moderator is critical. Ideally, the moderator should be
knowledgeable in the topic, but nonpartisan, and should have name recognition
to serve as a draw for the event. The choice of a moderator for the debate


provides an additional opportunity to broaden the scope of
activity by involving an individual not associated in the nor-
mal life of the department. The university community offered
many potential candidates. The role of the moderator is to
introduce the participants, keep discussion within the allotted
time, and to provide an overall summary of the discussion.

Topic Selection

Choice of the appropriate topic is very important. An appro-
priate topic should be of obvious relevance to a technically
educated audience, but of sufficient general interest so a
number of differing views might be anticipated. The topic
should also be reasonably accessible to those relatively unin-
formed about it, and there should be background and evi-
dence readily available through common media outlets, such
as magazines, journals, videotapes, and through the Internet.
For example, in the 1997 Exxon oil debate, the position
paper was a speech delivered by the Chairman and CEO of
Exxon Corporation, Lee Raymond (B.S., ChE., University
of Wisconsin 1960; PhD, ChE, University of Minnesota
1963) at the Economic Club of Detroit and published in Vital

Speeches of the Day.11l (Incidentally, reference 1 is a good
source of debate topics.)
It is important to note that whatever the position assigned
to debate (pro or con), the arguments should be grounded on
realities. In the case of the Exxon debate, the opposing
positions can be formulated as
"If I were in Lee Raymond's shoes, I would take
the same approach."
"If I were in Lee Raymond's shoes, I would take a
different approach."

Thus, if the position "...I would take a different approach"
was assigned, one has to argue from the point of a CEO who
is responsible to a Board of Directors, to shareholders, etc.,
backing the arguments with numbers and not on indefen-
sible, however lofty and heartfelt, environmental concerns.
In the case of the 1998 Monsanto debate, the central docu-
ments were an article on sustainable development[21 and an
interview with Monsanto's CEO, Robert Shapiro,[31 both
published in Harvard Business Review. Other debates were
grounded on more voluminous general literature. (See,
for example references 4 and 5. Reference 5, in particu-

Figure 1.



Chemical Engineering Education

Chemical Engineering Debate Format
Key: Pro-side:l, Con-side:2

1 Introduction/Executive Summary 2
5 minutes each

2 Moderator Question #1 1
4 minutes each

1 Moderator Question #2 2
4 minutes each

10 minute intermission

1 Audience Question to Pro side/ Rebuttal by Con side 2
3 minutes/2 minutes

2 Audience Question to Con side/ Rebuttal by Pro side 1
3 minutes/2 minutes

1 Conclusion 2
4 minutes each

1 Direct rebuttal of arguments 2
2 minutes each

lar, suggests several topics for debate.)

Structure of the Debate

We decided to incorporate both prepared and extemporane-
ous remarks in the debate program. Each side would have
opportunities to state its position initially in prepared re-
marks, and then to respond to questions posed by both the
moderator (presented to the teams in advance) and the audi-
ence (collected during the debate). A flow sheet of the typi-
cal debate structure is indicated in Figure 1.

Physical Arrangements

In order to separate the debate from the usual departmental
schedule of activities, we decided to schedule it in the early
evening, beginning at 7:00 p.m. and preceded by an informal
supper (an additional incentive for student attendees). Selec-
tion of a suitable room involved consideration of appropriate
space for seating of teams, the moderator, and the audience;
good sight lines and acoustics were also of major concern.
The ideal arrangement consists of two long tables, each
capable of seating the six members of the teams, with a
lectern in the middle for the debaters to address the audi-
ence. Ideally, the tables should be slanted in such a way that
they face each other and the audience, with a smaller mid
table for the moderator. Inevitably, some compromises are
necessary because of typically heavy demands on spaces
large enough to seat up to one hundred people.

Several variations on the above theme are possible.
Increasing the number of participants
Not all students have the inclination to share the spotlight
and to actually be debaters. A possibility for increasing
participation is to include "topic researchers." These people
actively seek material and participate in the briefing and
discussions, and they may take notes and prepare positions
for the rebuttal sections of the debate, but they do not partici-
pate in the public aspects of the debate.
Increasing spontaneity
Prepared questions make the debate seem "rigid." Alter-
natively, the questions posed by the moderator may not be
revealed to the teams in advance, thus forcing teams to
"think on their feet."
Increasing audience awareness
The audience may not be aware of the major issues in the
debate. Relevant background material might be posted on
the web prior to the debate.
Engaging the community
Often the best ideas occur after the debate is held. Fol-

low-up of the debate issues in relevant courses can extend
and increase the benefits of this activity.

Each of the four debate topics has served to engender
significant discussion among the students of the department.
The debates have provided a forum for discussion of these
timely topics and have been successful in bringing together
the faculty and students of all levels. Inevitably, a debate
creates an awareness in students for noticing and following a
topic in the news (Exxon was the most profitable company
in 1997; Monsanto's entry into the biotechnology market did
not anticipate the European resistance to genetically modi-
fied (GM) crops, etc.).
A brief survey of attendees at the most recent debate
indicated unanimous agreement that the debates should be
continued at a frequency of about twice a year (currently,
the plan is to stay with one debate a year). Respondents also
indicated that the most attractive aspects of the debates
were the interaction among students and faculty that they
produced and the focus on broad, socially relevant prob-
lems that they provided.
In view of these responses, coupled with our own convic-
tion that this program is indeed fulfilling our original expec-
tations, we plan to continue with the Chemical Engineering
Debates on an annual basis. We are particularly pleased that
this activity, which started with major input and direction
from faculty members, has now become institutionalized as
a student-directed and organized event, with the leadership
role undertaken by our AIChE Student Chapter in conjunc-
tion with the Graduate Student Forum, our departmental
graduate student organization.
We are also particularly pleased to note that this activity
has now been embraced by the larger Northwestern University
community. A series of once-a-quarter University-wide de-
bates has just been announced (and named "The Great De-
bates"). They will begin in the 2000-2001 academic year and
will address important topics cutting across all university lines.

1. Raymond, L.R., "Energy, the Economy, and the Environ-
ment," Vital Speeches of the Day, LXII(18), p. 546 (1996).
Delivered to the Economic Club of Detroit, May 6, 1996.
2. Magreta, J., "Growth Through Global Sustainability. An
Interview with Monsanto's CEO, Robert B. Shapiro,"
Harvard Business Review, p. 79, January-February (1997)
3. Hart, S.L., "Strategies for a Sustainable World," Harvard
Business Review, p. 67, February (1997)
4. Hoffman, A.J., From Heresy to Dogma: An Institutional
History of Corporate Environmentalism, Lexington Books,
San Francisco, CA (1997)
5. Hoffman, A.J., Competitive Environmental Strategy:A Guide
to the Changing Business Landscape, Island Press, Wash-
ington, DC (2000) J

Fall 2000

=--7-7 -7.

class and home problems

The object of this column is to enhance our readers' collections of interesting and novel
problems in chemical engineering. Problems of the type that can be used to motivate the student
by presenting a particular principle in class, or in a new light, or that can be assigned as a novel
home problem, are requested, as well as those that are more traditional in nature and that
elucidate difficult concepts. Manuscripts should not exceed ten double-spaced pages if possible
and should be accompanied by the originals of any figures or photographs. Please submit them to
Professor James O. Wilkes (e-mail:, Chemical Engineering Depart-
ment, University of Michigan, Ann Arbor, MI 48109-2136.



Universidad Sim6n Bolivar Caracas 1080, Venezuela

Thermodynamics course is particularly prone to
difficulties, both in teaching and in learning, prob-
ably because in most curricula it corresponds to one
of the first engineering courses in which it is not only neces-
sary to master the physics of the problem and the governing
equations, but also requires common sense to use them ap-
propriately. In a recent paper,"' Levenspiel showed how a
properly (or should we say "shrewdly") stated thermody-
namics problem can be used to point out deficiencies in
the use and teaching of certain concepts. Another of
these examples is presented here. It is an analog of "typi-
cal" textbook problems'[231 and apparently has two con-
flicting solutions.

Erich A. Miller is Professor at Simdn Bolivar
University (USB). He received his engineering
and MSc degree at USB and his PhD at Cornell
University. His research programs include mo-
lecular simulation of complex fluids and the
production of software for chemical engineer-
ing applications. He is author of the text
Termodindmica Basica (editorial Equinoccio,



Figure 1.
Consider two tanks, A and B, as shown in Figure 1. Both
are initially filled with the same gas, which for practical
purposes may be considered ideal. Initially, both tanks are at
the same temperature, T, but tank A is at a greater pressure
than tank B and is always kept at constant temperature by
means of heat transfer to the surroundings. On the other
hand, tank B is adiabatic. If the valve that connects both
tanks is opened and equilibrium is attained, will it have been
necessary to add (or to remove) heat from tank A?
The problem may also be stated quantitatively by giving
numerical values to the initial temperature, pressures, and
volumes. The problem may even be extended by asking for

Copyright ChE Division of ASEE 2000

Chemical Engineering Education

Levenspiel showed how a properly (or should we say "shrewdly") stated thermodynamics problem
can be used to point out deficiencies in the use and teaching of certain concepts. Another of
these examples in presented here. It is an analog of "typical" textbook
problems and apparently has two conflicting solutions.

an entropy and/or an availability balance. In any case, two
(and maybe more) solutions are readily found.


If one takes A as the system, one can apply the uniform
state approximation,*
QA =(mAu2 -mAu)+mA Ahe (2)

The ideal gas model holds, so the energies and enthalpies
can be substituted for their corresponding expressions*
(u=CvT; h=CpT). Since the temperatures do not change, the
enthalpy of the exiting fluid is constant and proportional to
the system temperature; thus

QA -mA -mA Cv +ACp]T = mA(C -Cv )T= mART (3)

Mass must be interchanged (due to the initial pressure
difference), and the mass exiting the tank A,
mA =(mA -m ), is a positive quantity. Since the RT term
is also positive, one concludes that QA>O.


If one considers both tanks and the valve as the system,
one may apply the first law to the closed system and obtain
Q=AU+W (4)
Since B is adiabatic, Q(=QA) will refer to the heat exchanged
by A. The system produces no work (W=0), and in the final
equilibrium state, the gas in both A and B will be at tempera-
ture T (since A is isothermal). For an ideal gas with no

* The uniform state, uniform flow process is an unsteady state in
which the mass that crosses the control surface has constant
thermodynamic properties. This allows an integrated first-law
Q+mihi =(m2u2-miu )+ymehe +W (1)
where "i" and "e" refer to incoming and exiting streams, respec-
tively, and 1 and 2 refer to the initial and final states. Q is the
heat added to the system. W is the work done by the system, and
m is mass. This equation is discussed in detail at the end of this
" With the implicit assumption that a reference state is taken as
u=O at T=O. This fact is, however, irrelevant to the solution, since
the heat capacities factor out.
"" Remember that for an ideal gas, the energy is only a function
of the temperature. In fact, the enthalpy h=u+Pv is also a
function of only the temperature since Pv=RT. For real gases, this
is no longer true.

temperature change, there is no change in internal energy*
(AU=mCvT=0) and therefore one concludes that QA=0.
Both solutions are obviously conflicting, but they both
seem to follow the "standard textbook resolutions." What
went wrong?

Comment on

the "Conflicting" Solutions

Solution #2 is the correct answer. Unfortunately, Solution
#1 is obtained by straightforward application of standard
control-volume equations as taught in classical textbooks. In
fact, there is nothing wrong with the development of solu-
tion #1. It is, however, incomplete. If we were to take a
control volume on tank B (the valve is isenthalpic and there-
fore irrelevant), one finds that

Q = mhi = m2u m u (5)
QB =(mCvT-mBCvT)-mBCpT=

m CvT-mpCpT=-m RT (6)

i.e., QB<0! But, this is in contradiction to the problem state-
ment. Since no heat transfer to the surroundings is allowed,
to maintain the final temperature of the whole system at T,
energy must leave tank B in an amount (not surprisingly)
equal to miRT(= mART). This energy will leave tank B and
enter tank A. Therefore, the net energy transfer to the sur-
roundings is zero. If the opening of the valve were sudden,
the most likely outcome of the system is that the pressures
would equate rather rapidly due to the corresponding mass
At this point, A will have decreased its temperature due to
adiabatic decompression, while B will have increased its
temperature due to an adiabatic compression. Given enough
time, this temperature gradient will produce a heat transfer
between the tanks. The final resulting temperature equilib-
rium temperature is T, requiring no external heat transfer.
Solution #1 is giving us only the half-time solution. In fact, it
does not take into account the final condition on the tem-
perature of tank B. The "trick" of the question is the phrase
"until equilibrium is attained" at the end of the problem
statement, since one could note that mechanical equilibrium
(equal pressures) does not imply thermal equilibrium.

Fall 2000

The system is analogous to Joule's experiment (see Figure
2) in which two tanks, one containing an ideal gas and the
other is evacuated, are put in contact by opening the valve in
the pipe joining them. The pressure in both tanks is equated,
but no temperature change is observed experimentally. (This
experiment is used to demonstrate how the internal energy
of ideal gases is a function only of their temperature, since
both heat and work are zero.)
Another interesting analog to the problem (see Figure 3) is
that of a single tank with an internal diathermic partition
where part of the system has adiabatic walls. At a given
moment the partition is eliminated and the system attains a
final homogeneous state. Notice how, in this analogy, the
adiabatic walls of B are irrelevant to the problem.

Comments on the Equation for the
Uniform State, Uniform Flow Model

At the start of Solution #1, a version of the first law for
uniform state is invoked. In order to obtain such an equation,
one must start with a generalized energy balance (first-law
equation for an open system)

Q+ m rih+-vel2 +gz -dE+ Ji h+ vel2+gz +W(7)
inlet exit
and integrate with respect to a time differential each element
of the equation. For some instances this is straightforward,
2 2 2
Qdt=J dQdt =dQ=Q (8)
I 1 1
but for the terms associated with the mass flow, a problem
arises: in principle, both the mass flow and the thermody-
namic properties of the system may vary with time, which
brings the dilemma that we must then attempt to evaluate
integrals of the type
jri(t)x(t)dt where x(t)may be h, -vel2, orgz (9)
These integrals may only be evaluated for the (unusual)
case in which the functionalities with time are known explic-
itly or for the case in which either (or both) m and x are
constant. In a general case, one makes the following as-
Assumption #1: "The properties of the mass entering or
leaving the control volume are constant." With this,
2 2
im(t)xdt=xjr(t)dt=xm (10)
1 1
but if the velocity and the thermodynamic properties are
constant, then how can the mass flow not be constant?

Figure 2


Figure 3

mn mV L
t t-=--=pA=pvelA (11)
t Vt t
in which A is the area for flow. This confusion can be
avoided if we make an additional assumption for the uni-
form state:
Assumption #2: "The kinetic and potential energy changes
are negligible compared to changes in internal energy," which
is generally true. The final assumption in the model is:
Assumption #3: "The system can be defined by a unique
thermodynamic state (therefore uniform state)." Thus, the
energy accumulation term can also be integrated as
2 2 2
dt dt
~dt m= J =jdU-U2--U= =mpue -ml u1 (12)

The final "working equation" for the Uniform State, Uni-
form Flow (USUF) model is then

Q+ mihi =(m2u2 -mlul)+ mehe +W (1)
Some textbooks13] do not make assumption #2 clear, while
othersl[2,4 (wisely?) do not present the uniform state as a
distinct model, preferring to categorize the open systems as
either steady state or unsteady state (transient).

1. Levenspiel, O., "Thermodynamics and Common Sense,"
Chem. Eng. Ed., 27(4), 206 (1993)
2. Qengel, Y.A., and Boles, M.A., Thermodynamics, 2nd ed.,
McGraw-Hill, New York, NY, Problem 6-126 (1994)
3. Sonntag, R., C. Borgnakke, and G. van Wylen, Fundamen-
tals of Thermodynamics, 5th ed., Wiley & Sons, New York,
NY, Problem 8-77 (1998)
4. Levenspiel, O., Understanding Engineering Thermo, Prentice
Hall, Englewood Cliffs, NJ (1996)

Chemical Engineering Education

Graduate Education Advertisements

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Fall 2000

Graduate Education in Chemical Engineering

Multiphase Processes,
Fluid Flow, Interfacial
Phenomena, Filtration,

L. K. JU
Biochemical Engineering,

Teaching and
research assistantships
as well as
industrially sponsored
up to

In addition to
tuition and fees
are waived.

PhD students
may get
some incentive

The deadline for
April 1st.

Nanocomposite Materials,
Sonochemical Processing,
Polymerization in
Nanostructured Fluids,
Supercritical Fluid

Catalysis, Reaction
Engineering, Environ-
mentally Benign

Molecular Simulation,
Phase Behavior, Physical
Properties, Process

Materials Processing and
CVD Modeling

BioMaterial Engineering
and Polymer Engineering

Surface Modification,
Polymer Thin film

Nonlinear Control,
Chaotic Processes

Biocatalysis and

For Additional Information, Write
Chairman, Graduate Committee
Department of Chemical Engineering The University of Akron Akron, OH 44325-3906
Phone (330) 972-7250 Fax (330) 972-5856

Chemical Engineering Education

Chemical Engineering

at the




A dedicated faculty with state-of-the-art facilities
offer research programs leading to Master of
Science and Doctor of Philosophy degrees.

Research Interests:
Biomass Conversion, Catalysis and Reactor
Design, Controlled Release, Energy Conversion
Processes, Environmental Studies, Fuel Cells,
Hydrodynamic Stability, Magnetic Storage Media,
Mass Transfer, Metal Casting, Microelectronic
Materials, Microencapsulation, Polymer Rheology,
Process Dynamics and Control, Reservoir
Modeling, Suspension and Slurry Rheology,
Thermodynamics, Transport Process Modeling

For Information Contai
Director of Graduate Studies
Department of Chemical Engineering
The University of Alabama
Box 870203
Tuscaloosa, AL 35487-0203
Phone: (205) 348-6450

An equal employment/equal educational
opportunity institution.

G.C. April, Ph.D. (Louisiana State)
D. W. Arnold, Ph.D. (Purdue)
C. S. Brazel, Ph.D. (Purdue)
E. S. Carlson, Ph.D. (Wyoming)
'. E. Clark, Ph.D. (Oklahoma State)
:. Clements, Jr., Ph.D. (Vanderbilt)
W. S. Epling, Ph.D. (Florida)
R. A. Griffin, Ph.D. (Utah State)
D. T. Johnson, Ph.D. (Florida)
T. M. Klein, Ph.D. (NC State)
A. M. Lane, Ph.D. (Massachusetts)
M. D. McKinley, Ph.D. (Florida)
R. G. Reddy, Ph.D. (Utah)
L. Y. Sadler III, Ph.D. (Alabama)
V. N. Schrodt, Ph.D. (Penn. State)
J. M. Wiest, Ph.D. (Wisconsin)

Fall 2000



The Department of Chemical and
Materials Engineering at The University of
Alabama in Huntsville offers you the
opportunity for a solid and rewarding
graduate career that will lead to further
success at the forefront of academia and
We will provide graduate programs
that educate and train students in
advanced areas of chemical engineering,
materials science and engineering, and
biotechnology. Options for an M.S. and
Ph.D. degree in Engineering or Materials
Science are available.
Faculty members are dedicated to inter-
national leadership in research. Projects
are ongoing in Mass Transfer, Fluid
Mechanics, Combustion, Bioseparations,
Biomaterials, Microgravity Materials
Processing, and Adhesion. Collaborations
have been established with nearby
NASA/Marshall Space Flight Center as
well as leading edge biotechnology and
engineering companies.
We are also dedicated to innovation in
teaching. Our classes incorporate
advances in computational methods and
multi-media presentations.

Department of Chemical Engineering
The University of Alabama in Huntsville
130 Engineering Building
Huntsville, AL 35899


Ram6n L. Cerro Ph.D. (UC-Davis) Professor and Chair
Capillary hydrodynamics, multiphase flows, enhanced heat
transfer surfaces.
(256) 890-7313,

Chien P. Chen Ph.D. (Michigan State) Professor
Multiphase flows, spray combustion, turbulence modeling, numerical
methods in fluids and heat transfer.
(256) 890-6194,

Krishnan K. Chittur Ph.D. (Rice) Professor
Protein Adsorption to Biomaterials, FTR/ATR at solid-liquid interfaces,
(256) 890-6850,

Douglas G. Hayes Ph.D. (Michigan) Assistant Professor
Enzyme reactions in nonaqueous media, separations involving
biomolecules, lipids and surfactants, surfactant-based collidal aggregates.
(256) 890-6874,

James E. Smith Jr. Ph.D. (South Carolina) Professor
Kinetics and catalysis, powdered materials processing, combustion
diagnostics and fluids visualization using optical methods.
(256) 890-6439,

Jeffrey J. Weimer Ph.D. (MIT)
Associate Professor, Joint Appointment in Chemistry
Adhesion, biomaterials surface properties, thin film growth, surface
spectroscopies, scanning probe microscopies.
(256) 890-6954,

Natacha DePaola Ph.D. (Harvard-MIT)
Associate Professor
Biofluid dynamics, cell and tissue engineering
(256) 890-6473,

The University of Alabama in Huntsville
An Affirmative Action/Equal Opportunity Institution
Web page:
Ph: 256.890.6810 FAX: 256.890.6839

The University of Alberta is well
known for its commitment to excel-
lence in teaching and research. The
Department of Chemical and Materi-
als Engineering has 34 professors and
over 100 graduate students. Degrees
are offered at the M.Sc. and Ph.D.
levels in Chemical Engineering, Ma-
terials Engineering, and Process
Control. All full-time graduate stu-
dents in the research programs re-
ceive a stipend to cover living ex-
penses and tuition.

For further information, contact
Graduate Program Officer
Department of Chemical and Materials Engineering
University of Alberta
Edmonton, Alberta, Canada T6G 2G6
PHONE (780) 492-1823 FAX (780) 492-2881


P. CHOI, Ph.D. (University of Waterloo)
Statistical Mechanics of Polymers Polymer Solutions and Blends
K. T. CHUANG, Ph.D. (University of Alberta)
Mass Transfer Catalysis Separation Processes Pollution Control
I. G. DALLA LANA, Ph.D. (Univ. of Minnesota) EMERITUS
Chemical Reaction Engineering Heterogeneous Catalysis
J. A. W. ELLIOTT, Ph.D. (University of Toronto)
Thermodynamics Statistical Thennodynamics Interfacial Phenomena
D. G. FISHER, Ph.D. (University of Michigan) EMERITUS
Process Dynamics and Control Real-Time Computer Applications
J.F. FORBES, Ph.D. (McMaster University)
Real-Time Optimization Control of Sheet Forming Processes
M. R. GRAY, Ph.D. (California Inst. of Tech.)
Bioreactors Chemical Kinetics Bitumen Processing
R. E. HAYES, Ph.D. (University of Bath)
Numerical Analysis Reactor Modeling Computational Fluid Dynamics
B. HUANG, Ph.D. (University of Alberta)
Controller Performance Assessment Multivariable Control Statistics
S. M. KRESTA, Ph.D. (McMaster University)
Turbulent & Transitional Flows Multiphase Flows CFD
S. LIU, Ph.D. (University of Alberta)
Fluid-Particle Dynamics Transport Phenomena Mass Transfer
D. T. LYNCH, Ph.D. (University of Alberta) DEAN OF ENGINEERING
Catalysis Kinetic Modeling Numerical Methods Polymerization
J. H. MASLIYAH, Ph.D. (University of British Columbia)
Transport Phenomena Colloids Particle-Fluid Dynamics Oil Sands
A. E. MATHER, Ph.D. (University of Michigan)
Phase Equilibria Fluid Properties at High Pressures Thermodynamics
E. S. MEADOWS, Ph.D. (University of Texas)
Process Control Model Predictive Control Optimization
W. C. MCCAFFREY, Ph.D. (McGill University)
Reaction Kinetics Heavy Oil Upgrading Polymer Recycling Biotechnology
K. NANDAKUMAR, Ph.D. (Princeton University)
Transport Phenomena Distillation Computational Fluid Dynamics
M. RAO, Ph.D. (Rutgers University)
Al Intelligent Control Process Control
S. L. SHAH, Ph.D. (University of Alberta)
Computer Process Control System Identification Adaptive Control
U. SUNDARARAJ, Ph.D. (University of Minnesota)
Polymer Processing Polymer Blends Interfacial Phenomena
S. E. WANKE, Ph.D. (University of California, Davis) CHAIR
Heterogeneous Catalysis Kinetics Polymerization
M. C. WILLIAMS, Ph.D. (University of Wisconsin)
Rheology Polymer Characterization Polymer Processing
Z. XU, Ph.D. (Virginia Polytechnic Institute and State University)
Surface Science & Engineering Mineral Processing Waste Management
T. YEUNG, Ph.D. (University of British Columbia)
Emulsions Interfacial Phenomena Micromechanics

Fall 2000

ROBERT ARNOLD, Professor (CalTech)
Microbiological Hazardous Waste Treatment, Metals Speciation and Toxici
PAUL BLOWERS, Assistant Professor (Illinois, Urbana-Champaign)
Chemical Kinetics, Catalysis, Surface Phenomena
JAMES BAYGENTS, Associate Professor (Princeton)
Fluid Mechanics, Transport and Colloidal Phenomena, Bioseparations,
WENDELL ELA, Assistant Professor (Stanford)
Particle-Particle Interactions, Environmental Chemistry
JAMES FARRELL, Associate Professor (Stanford)
Sorption/desorption of Organics in Soils
JAMES A. FIELD, Associate Professor (Wagenigen Agricultural University)
Bioremediation, Microbiology, White Rot Fungi, Hazardous Waste
ROBERTO GUZMAN, Associate Professor (North Carolina State)
Affinity Protein Separations, Polymeric Surface Science
ANTHONY MUSCAT, Assistant Professor (Stanford)
Kinetics, Surface Chemistry, Surface Engineering, Semiconductor Processin
KIMBERLY OGDEN, Associate Professor (Colorado)
Bioreactors, Bioremediation, Organics Removal from Soils
THOMAS W. PETERSON, Professor and Dean (CalTech)
Aerosols, Hazardous Waste Incineration, Microcontamination
ARA PHILIPOSSIAN, Adjunct Associate Professor (Tufts)
Chemical/Mechanical Polishing, Semiconductor Processing
JERKER PORATH, Research Professor (Uppsala)
Separation Science
EDUARDO SAEZ, Associate Professor (UC, Davis)
Rheology, Polymer Flows, Multiphase Reactors
FARHANG SHADMAN, Professor (Berkeley)
Reaction Engineering, Kinetics, Catalysis, Reactive Membranes,
RAYMOND A. SIERKA, Professor Emeritus (Oklahoma)
Adsorption, Oxidation, Membranes, Solar Catalyzed Detox Reactions
JOST 0. L. WENDT, Professor and Head (Johns Hopkins)
Combustion-Generated Air Pollution, Incineration, Waste
DON H. WHITE, Professor Emeritus (Iowa State)
Polymers, Microbial and Enzymatic Processes
DAVID WOLF, Visiting Professor (Technion)
Fermentation, Mixing, Energy, Biomass Conversion

For further information, write to
OR write
Chairman, Graduate Student Committee
Department of Chemical and
Environmental Engineering
P.O. 210011
The University of Arizona
Tucson, AZ 85721
The University of Arizona is an equal
opportunity educational institution/equal opportunity employer.
Women and minorities are encouraged to apply.









OF i


The Chemical and Environmental Engineering Department
at the University of Arizona offers a wide range of research
opportunities in all major areas of chemical engineering and
environmental engineering, and graduate courses are offered in
most of the research areas listed here. The department offers a fully
accredited undergraduate degree as well as MS and PhD graduate
degrees. Strong interdisciplinary programs exist in bioprocessing
and bioseparations, microcontamination in electronics manu-
facture, and environmental process modification.
Financial support is available through fellowships, government
and industrial grants and contracts, teaching and
research assistantships.
Tucson has an excellent climate and many
recreational opportunities. It is a growing modern city that
retains much of the old Southwestern atmosphere.

Chemical Engineering Education




Department of Chemical and

Materials Engineering

Chemical Engineerins
Jon Allen, Ph.D., Massachusetts Institute of Technology
Atmospheric chemistry
Stephen Beaudoin, Ph.D., North Carolina State University *
Environmentally-benign semiconductor manufacturing, Adhesion
James Beckman, Ph.D., University of Arizona Low energy water
purification, Desalination, Unit operations
Neil Berman (Emeritus), Ph.D., University of Texas, Austin Fluid
dynamics, Air pollution
Veronica Burrows, Ph.D., Princeton University Surface science
and engineering, Semiconductor processing
Ann Dillner, Ph.D., University of Illinois, Urbana-Champaign *
Atmospheric chemistry
Gregory Raupp, Ph.D., University of Wisconsin Semiconductor
materials processing, Surface science, Photocatalysis
Anneta Razatos, Ph.D., University of Texas, Austin Biotechnology,
Bacterial and cellular adhesion, biomaterials
Daniel Rivera, Ph.D., California Institute of Technology Process
identification and control
Gene Sater, Ph.D., Illinois Institute of Technology Unit operations
Michael Sierks, Ph.D., Iowa State University Biotechnology,
Biochemical therapies for neurodegenerative diseases

A multi-disciplinary research
environment with opportunities in
electronic materials processing *
biotechnology processing,
characterization and simulation
of materials air and water
purification air pollution *
process control.

Materials Science and Engineering
James Adams, Ph.D., University of Wisconsin Atomistic simulation
of metallic surfaces, Grain boundaries, Catalysts, Polymer-metal
Terry Alford, Ph.D., Cornell University Electronic materials,
Physical metallurgy, Electronic thin films
Nikhilesh Chawla Ph.D., University of Michigan Lead-free solders,
Composite materials, Powder metallurgy
Sandwip Dey, Ph.D., Alfred University Ceramics, High-K dielectrics, Sol-gel processing
Stephen Krause, Ph.D., University of Michigan Growth and processing of semiconductors
Subhash Mahajan (Chair), Ph.D., University of California, Berkeley Semiconductor defects, High temperature
semiconductors, Structural materials deformation
James Mayer, Ph.D., Purdue University Thin film processing, Ion beam modification of materials
Nate Newman, Ph.D., Stanford University Growth, characterization and modeling of solid state materials

For details concerning graduate opportunities in Chemical and Materials Engineering at ASU, please
call Linda Boucher at (480) 965-3313, or write to Subhash Mahajan, Chair, Chemical and Materials
Engineering, Arizona State University, Tempe, Arizona 85287-6006 (

Fall 2000


Chemical Engineering

Robert P. Chambers University of California, Berkeley
Harry T. Cullinan Carnegie Mellon University
Christine W. Curtis Florida State University
Steve R. Duke University of Illinois
Mahmoud EI-Halwagi University of California, Los Angeles
Said Elnashaie University of Edinburgh
James A. Guin L narc'rsi ol leias, .iAstin
Gopal A. Krishnagopalan L ntersin ol' larn:
V. 1. Lee loa tate I t'111ersin1
Glennon Maples Oklahoma Stat L ni. itrs
Ronald D. Neuman Ihe Inwrntue of Paper (Chlemfnfrn
Stephen A. Perusich L n mersin of IlhinoL
Timolhy D. Placek i'nn crsi of Kenntcks
Christopher B. Roberts L'ni.erstrr of ,otr Dame
A. R. Tarrer- Purdue L'n rii rsit .
Bruce J. Talarchuk I nit ers's of It usconsi

,-./?.aA*^!; .:.'_-:^ ~ T~ -;liH nn.aL^^ .*^, .^ ..* L '

Research Areas
m Biochemical Engineering
* Pulp and Paper
m Process Systems Engineering
n Integrated Process Design
m Environmental Chemical Engineering
m Catalysis and Reaction Engineering
n Materials Polymers
m Surface and Interfacial Science
" Thermodynamics Supercritical Fluids
* Electrochemical Engineering
" Transport Phenomena

--Ja 7

_.l8a-4e-; _C --

Inquiries to:
i'.1 Director of Graduate Recruiring
,, iDepartment of Chemical Engineering
,t Auburn Uni ersii..AL 3b'S4
Phone (33418a4.4-482
Fax (33) 844.2063
e email:
Financial assistance is a ailable to qualhied applicanLs.
-:, ,, -~ E~~:., .. ,. .. -- ',-: .; =, ,f.,.,- ;.

Chemical Engineering Education



R. G. Moore, Head (Alberta)
J. Azaiez (Stanford)
H. Baheri (Saskatchewan)
L. A. Behie (Western Ontario)
C. Bellehumeur (McMaster)
P. R. Bishnoi (Alberta)
P. J. Farrell (Calgary)
R. A. Heidemann (Washington U.)
C. Hyndman (Ecole Polytechnique)
A. A. Jeje (MIT)
M. S. Kallos (Calgary)
A. Kantzas (Waterloo)
B. B. Maini (Univ. Washington)
A. K. Mehrotra (Calgary)
S. A. Mehta (Calgary)
B. J. Milne (Calgary)
M. Pooladi-Darvish (Alberta)
S. Srinivasan (Stanford)
W. Y. Svrcek (Alberta)
M. A. Trebble (Calgary)
H. W. Yarranton (Alberta)
B. Young (Canterbury, NZ)
I. Zanzattn (Slovak Tech. Univ.. Czechoslovakia,

The Department offers graduate programs leading to the M.Sc. and Ph.D.
degrees in Chemical Engineering (full-time) and the M.Eng. degree in Chemical
Engineering, Petroleum Reservoir Engineering or Engineering for the
Environment (part-time) in the following areas:
Biochemical Engineering & Biotechnology
Biomedical Engineering
Environmental Engineering
Modeling, Simulation & Control
Petroleum Recovery & Reservoir Engineering
Polymer Processing & Rheology
Process Development
Reaction Engineering/Kinetics
Transport Phenomena
Fellowships and Research Assistantships are available to all qualified applicants.

SFor Additional Information Write *
Dr. A. K. Mehrotra Chair, Graduate Studies Committee
Department of Chemical and Petroleum Engineering
University of Calgary Calgary, Alberta, Canada T2N 1N4

The University is located in the City of Calgary, the Oil capital of Canada, the home of the world famous Calgary Stampede and the
1988 Winter Olympics. The City combines the traditions of the Old West with the sophistication of a modern urban center. Beautiful
Banff National Park is 110 km west of the City and the ski resorts of Banff, Lake Louise,and Kananaskis areas are readily accessible. In
the above photo the University Campus is shown with the Olympic Oval and the student residences in the foreground. The Engineering
complex is on the left of the picture. I-.....-....- .



Fall 2000









. offers graduate programs leading to the
Master of Science and Doctor of Philosophy.
Both programs involve joint faculty-student
research as well as courses and seminars within
and outside the department. Students have the
opportunity to take part in the many cultural
offerings of the San Francisco Bay Area and
the recreational activities of California's north-
ern coast and mountains.


Biochemical Engineering
Electrochemical Engineering
Electronic Materials Processing
Energy Utilization
Fluid Mechanics
Kinetics and Catalysis
Polymer Science and Technology
Process Design and Development
Separation Processes
Surface and Colloid Science












Chemical Engineering Education


University of California, Davis

Department of Chemical Engineering & Materials Science
Offering M.S. and Ph.D. degree programs in both Chemical Engineering and Materials Science and Engineering

Faculty u

David E. Block, Assistant Professor Ph.D., University of Minnesota, 1992 Industrialfermentation, biochemical processes in pharmaceutical
Roger B. Boulton, Professor Ph.D., University of Melbourne, 1976 Fermentation and reaction kinetics, crystallization
Stephanie R. Dungan, Associate Professor Ph.D., Massachusetts Institute of Technology, 1992 Micelle transport, colloid and interfacial
science in food processing
Bruce C. Gates, Professor Ph.D., University of Washington, Seattle, 1966 Catalysis, solid superacid catalysis, zeolite catalysts, bimetallic
catalysts, catalysis by metal clusters
Jeffery C. Gibeling, Professor Ph.D., Stanford University, 1979 Defonnation, fracture andfatigue of metals, layered composites and bone
Joanna R. Groza, Professor Ph.D.. Polytechnic Institute. Bucharest, 1972 Plasma activated sintering and processing of nanostructured
Brian G. Higgins, Professor Ph.D., University of Minnesota. 1980 Fluid mechanics and interfacialphenomena, sol gelprocessing, coatingflows
David G. Howitt, Professor Ph.D., University of California, Berkeley, 1976 Forensic andfailure analysis, electron microscopy, ignition and
combustion processes in materials
Alan P. Jackman, Professor Ph.D., University of Minnesota. 1968 Protein production in plant cell cultures, bioremediation
Tonya L. Kuhl, Assistant Professor Ph.D., University of California, Santa Barbara, 1996 Biomaterials, membrane interactions, intermolecular
and intersurfaceforces in complex fluid systems
Marjorie L. Longo, Assistant Professor Ph.D., University of California. Santa Barbara. 1993 Hydrophobic protein design for active control,
surfactant microstructure, and interaction of proteins and DNA with biological membranes
Benjamin J. McCoy, Professor Ph.D., University of Minnesota, 1967 Supercritical extraction, pollutant transport
Karen A. McDonald, Professor Ph.D., University of Maryland, College Park, 1985 Plant cell culture bioprocessing algal cell cultures
Amiya K. Mukherjee, Professor D.Phil., University of Oxford. 1962 Superplasticity of intermetallic alloys and ceramics, high temperature
creep deformation
Zuhair A. Munir, Professor Ph.D., University of California, Berkeley, 1963 Combustion synthesis, multilayer combustion systems, functionally
graded materials
Alexandra Navrotsky, Professor Ph.D.. University of Chicago. 1967 Thermodynamics and solid state chemistry; high temperature calorimetrn
Ahmet N. Palazoglu, Professor Ph.D., Rensselaer Polytechnic Institute, 1984 Process control and process design of environmentally benign
Ronald J. Phillips, Associate Professor Ph.D., Massachusetts Institute of Technology, 1989 Transport processes in bioseparations, Newtonian
and non-Newtonian suspension mechanics
Robert L Powell, Professor Ph.D., Johns Hopkins University, 1978 Rheology, suspension mechanics, magnetic resonance imaging of
Snbhash H. Risbud, Professor and Chair Ph.D., University of California, Berkeley, 1976 Semiconductor quantum dots, high T, superconducting
ceramics, polymer compositesfor optics
Dewey D.Y. Ryu, Professor Ph.D., Massachusetts Institute of Technology, 1967 Biomolecular process engineering and recombinant bioprocess
James F. Shackelford, Professor Ph.D., University of California, Berkeley, 1971 Structure ofmaterials, biomaterials, nondestructive testing of
engineering materials
J.M. Smith, Professor Emeritus Sc.D., Massachusetts Institute of Technology. 1943 Chemical kinetics and reactor design
Pieter Stroeve, Professor Sc.D., Massachusetts Institute of Technology, 1973 Membrane separations, Langmuir Blodgett films, colloid and
surface science
QCbnhan Prnfop rr Ph n) I lnivrcitv nf Dllutarp 1 00 M Ultinhfh trancnart nhnmann


Sacramento: 17 mil
Sn Frandsco 72 miler
Lake Tahoe: 90 mile

Davis is a small, bike-friendly university town
located 17 miles west of Sacramento and 72 miles
northeast of San Francisco, within driving dis-
tance of a multitude of recreational activities in
Yosemite, Lake Tahoe, Monterey, and San Fran-
cisco Bay Area.

For information about our program, look up our web
site at
or contact us via e-mail at
On-line applications may be submitted via
Graduate Admission Chair
Professor Jeffery C. Gibeling
Department of Chemical Engineering & Materials Science
University of California, Davis
One Shields Avenue
Davis, CA 95616-5294, USA
Phone (530) 752-7952 Fax (530) 752-1031

Fall 2000

The multifaceted graduate study experience in the Department
of Chemical Engineering and Materials Science allows students to
choose research projects and thesis advisers from any of our faculty
with expertise in chemical engineering and/or materials science and
Our goal is to provide the financial and academic support for
students to complete a substantive research project within 2 years
for the M.S. and 4 years for the Ph.D.



Graduate Studies in IVI
Chemical and Biochemical Engineering VIN
and Materials Science and Engineering
for Chemical Engineering, Engineering, and Science Majors
Offering degrees at the M.S. and Ph.D. levels. Research in frontier areas
in chemical engineering, biochemical engineering, biomedical engineering, and materials
science and engineering. Strong physical and life science and engineering groups on campus.
Ying Chih Chang (Stanford University)
Nancy A. Da Silva (California Institute of Technology)
James C. Earthman (Stanford University)
Steven C. George (University of Washington)
Stanley B. Grant (California Institute of Technology)
Juan Hong (Purdue University)
Enrique J. Lavernia (Massachusetts Institute of Technology)
Henry C. Lim (Northwestern University)
Martha L. Mecartney (Stanford University)
Farghalli A. Mohamed (University of California, Berkeley)
Frank G. Shi (California Institute of Technology)
Vasan Venugopalan (Massachusetts Institute of Technology)
Joint Appointments:
G. Wesley Hatfield (Purdue University)
Roger H. Rangel (University of California, Berkeley)
William A. Sirignano (Princeton University)
Adjunct Professors
Peggy Arps (Johns Hopkins University)
Russell Chou (Carnegie Mellon University)
Andrew Shapiro (University of Califoria, Irvine)

The 1,510-acre UC Irvine campus is in Orange County, five miles from the Pacific Ocean and 40 miles
south of Los Angeles. Irvine is one of the nation's fastest growing residential, industrial, and business
areas. Nearby beaches, mountain and desert area recreational activities, and local cultural activities
make Irvine a pleasant city in which to live and study.
For further information and application forms, please visit
or contact
Department of Chemical and Biochemical Engineering and Materials Science
School of Engineering University of California Irvine, CA 92697-2575

* Biomedical
Control and
Processing and
of Materials
and Glass
Cell Technol-
So]-Gel Process-
* Water Pollution

Chemical Engineering Education





* Aerosol Science and Technology
* Biochemical Engineering
* Combinatorial Catalysis
* Electrochemistry
* Molecular and Cellular
* Molecular Simulations
* Pollution Prevention
* Polymer Processing and
* Process Design, Dynamics, and
* Reaction Kinetics and Combus-
* Semiconductor Manufacturing

J. P. Chang
P. D. Christofides
Y. Cohen
James Davis
(Associate Chancellor for
Information Technology
M. W. Deem
T. H. K. Frederking
(Prof Emeritus)
S. K. Friedlander
R. F. Hicks
E. L. Knuth (Prof. Emeritus)
J. C. Liao
V. Manousiouthakis
H. G. Monbouquette
K. Nobe
L. B. Robinson (Prof Emeritus)
S. M. Senkan
W. D. Van Vorst (Prof. Emeritus)
V. L. Vilker (Prof. Emeritus)
A. R. Wazzan
(Dean of Engineering)


UCLA's Chemical Engineering Department offers a
program of teaching and research linking fundamental
engineering science and industrial practice. Our Depart-
ment has strong graduate research programs in Bioengi-
neering, Energy and Environment, Semiconductor Manu-
facturing, Molecular Engineering of Materials, and Pro-
cess Systems Engineering.
Fellowships are available for outstanding applicants in

Ph.D. degree programs. A fellowship includes a waiver
of tuition and fees plus a stipend.
Located five miles from the Pacific Coast,
UCLA's attractive 417-acre campus extends from
Bel Air to Westwood Village. Students have access
to the highly regarded science programs and to a
variety of experiences in theatre, music, art, and
sports on campus.


Admissions Officer Chemical Engineering Department rl ;r
3 H A ngeles A 900
Teehn at (30 82-96 or vii us. at wwwhemegucaed

Fall 2000

University of California, Riverside
Department of Chemical and Environmental Engineering

The Graduate Program in Chemical and En- arlan and Rosemary Bourns College of
vironmental Engineering offers training lead-
ing to the degrees of Master of Science and ng/n eeri ng
Doctor of Philosophy. All applicants are re-
quired to submit scores from the general ap-
titude Graduate Record Examination (GRE).
For more information and application mate-
rials, write:
Graduate Advisor
Department of Chemical and
Environmental Engineering
University of California
Riverside CA 92521
Visit us at our website:

Wilfred Chen (Cal Tech) Environmental Biotechnology, Microbial Engineering, Biocatalysis
Marc Deshusses (ETH, Zurich) Environmental Biotechnology, Bioremediation, Modeling

Robert C. Haddon (Penn State) Nanotubes, Applied Materials

Mark R. Matsumoto, Chair (UC Davis) Water and Wastewater Treatment, Soil Remediation

Ashok Mulchandani (McGill) Biocatalysis, Biosensors, Environmental Biotechnology
Joseph M. Norbeck (Nebraska) Advanced Vehicle Technology, Air Pollution, Renewable Fuels

Akula Venkatram (Purdue) Micrometeorology, Air Pollution Modeling

Anders O. Wistrom (UC Davis) Colloidal Interactions and Transport, Surface Forces

Jianzhong Wu (UC Berkeley) Molecular Simulation, Nanomaterials, DNA Separation
Yushan Yan (CalTech) Advanced Materials, Zeolite Thin Films, and Nanocrystals

The 1,200-acre Riverside campus of the University of California is conveniently located
50 miles east of Los Angeles within easy driving distance to most of the major cultural
and recreational offerings in Southern California. In addition, it is virtually
equidistant from the desert, the mountains, and the ocean.


Chemical Engineering Education



ERAY S. AYDIL Ph.D. (Houston) Microelectronics and Plasma Processing
SANJOY BANERJEE Ph.D. (Waterloo) Environmental Fluid Dynamics, Multiphase Flows, Turbulence, Computational Fluid Dynamics
BRADLEY F. CHMELKA Ph.D. (U.C. Berkeley) Inorganic-Organic Hybrid Materials, Zeolites and Molecular Sieves, Polymeric Solids, Liquid
Crystals, Solid-State NMR
PATRICK S. DAUGHERTY Ph.D. (Austin) Protein Engineering and Design, Library Technologies
MICHAEL F. DOHERTY Ph.D. (Cambridge) Design and Synthesis, Separations, Process Dynamics and Control
GLENN H. FREDRICKSON Ph.D. (Stanford) (Chair) Statistical Mechanics, Glasses, Polymers, Composites, Alloys
JACOB ISRAELACHVILI Ph.D. (Cambridge) Colloidal and Biomolecular Interactions, Adhesion and Friction
EDWARD J. KRAMER Ph.D. (Carnegie-Mellon) Fracture and Diffusion of Polymers, Polymer Surfaces and Interfaces
FRED F. LANGE Ph.D. (Penn State) Powder Processing of Composite Ceramics, Liquid Precursors for Ceramics, Superconducting Oxides
L. GARY LEAL Ph.D. (Stanford) Fluid Mechanics, Physics and Rheology of Complex Fluids, including Polymers, Suspensions, and Emulsions.
GLENN E. LUCAS Ph.D. (M.I.T.) Mechanics of Materials, Structural Reliability.
DIMITRIOS MAROUDAS Ph.D. (M.I.T.) Theoretical and Computational Materials Science, Electronic and Structural Materials
ERIC McFARLAND Ph.D. (M.I.T.) M.D. (Harvard) Combinatorial Material Science, Environmental Catalysis, Surface Science
DUNCAN A. MELLICHAMP Ph.D. (Purdue) Computer Control, Process Dynamics, Real-Time Computing
SAMIR MITRAGOTRI Ph.D. (M.I.T.) Drug Delivery and Biomaterials
DAVID J. PINE Ph.D. (Cornell) Polymer, Surfactant, and Colloidal Physics, Multiple Light Scattering, Photonic Crystals
ORVILLE C. SANDALL Ph.D. (Berkeley) Transport Phenomena, Separation Processes
DALE E. SEBORG Ph.D. (Princeton) Process Control, Monitoring and Identification
MATTHEW V. TIRRELL Ph.D. (Massachusetts) Polymers, Surfaces, Adhesion Biomaterials
T. G. THEOFANOUS Ph.D. (Minnesota) Multiphase Flow, Risk Assessment and Management
JOSEPH A. ZASADZINSKI Ph.D. (Minnesota) Surface and Interfacial Phenomena, Biomaterials

The Department offers M.S. and
Ph.D. degree programs Finan-
cial aid, including fellowships,
teaching assistantships, and re-
search assistantships, is avail-
One of the world's few seashore
campuses, UCSB is located on
the Pacific Coast 100 miles
northwest of Los Angeles. The
student enrollment is over
18,000. The metropolitan Santa
Barbara area has over 150,000
residents and is famous for its
mild, even climate.

For additional information
and applications, write to
Chair Graduate Admissions Committee Department of Chemical Engineering University of California Santa Barbara, CA 93106

Fall 2000

Chemical Engineering at the





"At the Leading Edge"

Frances H. Arnold
Anand R. Asthagiri
John F. Brady
Mark E. Davis


Richard C. Flagan
George R. Gavalas
Konstantinos P. Giapis
Julia A. Kornfield
John H. Seinfeld

David A. Tirrell
Nicholas W. Tschoegl
Zhen-Gang Wang

Aerosol Science
Applied Mathematics
Atmospheric Chemistry and Physics
Biocatalysis and Bioreactor Engineering
Biomedical Engineering
Chemical Vapor Deposition

Colloid Physics
Fluid Mechanics
Materials Processing
Microelectronics Processing
Microstructured Fluids
Polymer Science
Protein Engineering
Statistical Mechanics

For further information, write
Director of Graduate Studies
Chemical Engineering 210-41 California Institute of Technology Pasadena, California 91125-4100
Also, visit us on the World Wide Web for an on-line brochure:
Chemical Engineering Education


Department Home Page

On-line Graduate Application
Contact Information

Graduate Degree Programs
Course opron Masiers
Tnesis option Masters
Research Thrust Areas
Complex Fluids Engineering
Envirochemical Engineering
Process Systems Engineering
Solid State Materials

lartment of Chemical Engineering Camegie Mellon University Pittsburgh, PA 15213-3890


I :



0 IN 10 12 2:1 Vi It~

Opportunities for Graduate Study in Chemical Engineering at the

M.S. and Ph.D. Degrees in Chemical Engineering


Amy Ciric

Joel Fried

Rakesh Govind

Vadim Guliants

Daniel Hershey

Sun-Tak Hwang

Robert Jenkins

Yuen-Koh Kao

Soon-Jai Khang

William Krantz

Y. S. Lin

Neville Pinto

Sotiris Pratsinis

Peter Smirniotis


The University of Cincinnati is
committed to a policy of
non-discrimination in
awarding financial aid.

For Admission Information
Director, Graduate Studies
Department of Chemical Engineering
PO Box 210171
University of Cincinnati
Cincinnati, Ohio 45221-0171

The faculty and students in the Department of Chemical Engineering are engaged in a diverse
range of exciting research topics. Assistantships and tuition scholarships are available to highly
qualified applicants to the MS and PhD degree programs.

O Biotechnology (Bioseparations)
Novel bioseparation techniques, chromatography, affinity separations, biodegradation of
toxic wastes, controlled drug delivery, two-phase flow, suspension rheology.
l Chemical Reaction Engineering and Heterogeneous Catalysis
Modeling and design of chemical reactors, deactivation of catalysts, flow pattern and
mixing in chemical equipment, laser induced effects.

L Coal Research
New technology for coal combustion power plant, desulfurization and denitritication.

O Material Synthesis
Manufacture of advanced ceramics, opticalfibers and pigments by aerosol processes.
L Membrane Separations
Membrane gas separations, membrane reactors, sensors and probes, pervaporation,
dynamic simulation of membrane separators, membrane preparation and characteriza-
tion for polymeric and inorganic materials, inorganic membranes.
L Particle Technology
Flocculation of liquid suspensions, granulation offine powders, grinding of agglomerate
L Polymers
Thermodynamics, polymer blends and composites, high-temperature polymers,
hydrogels, rheology, computational polymer science.

L Process Synthesis
Computer-aided design methodologies, design for waste minimization, design for
dynamic stability, separation system synthesis.

Chemical Engineering Education

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