Immobilization of Dissolved and Particulate Copper Using Lime/Biochar and Characterization of Nanoparticles in Soils

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Material Information

Title:
Immobilization of Dissolved and Particulate Copper Using Lime/Biochar and Characterization of Nanoparticles in Soils
Physical Description:
1 online resource (220 p.)
Language:
english
Creator:
Bakshi, Santanu
Publisher:
University of Florida
Place of Publication:
Gainesville, Fla.
Publication Date:

Thesis/Dissertation Information

Degree:
Doctorate ( Ph.D.)
Degree Grantor:
University of Florida
Degree Disciplines:
Soil and Water Science
Committee Chair:
HE,ZHENLI
Committee Co-Chair:
HARRIS,WILLIE G,JR
Committee Members:
WILSON,PATRICK CHRISTOPHER
MA,LENA Q
GHIVIRIGA,ION

Subjects

Subjects / Keywords:
biochar -- copper -- immobilization -- lime -- nanoparticles -- nutrients
Soil and Water Science -- Dissertations, Academic -- UF
Genre:
Soil and Water Science thesis, Ph.D.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract:
Soil contamination by copper (Cu) is a worldwide concern, especially in South Florida where Cu-based fungicides have been extensively used in agriculture. In this study, laboratory incubation, chemical characterization, speciation, and column leaching were conducted to evaluate lime and biochar as potential amendments for remediation of Cu-contaminated soils. Soil available Cu estimated by CaCl2, NH4OAc, or Mehlich-3 extraction significantly increased with external Cu loads and decreased with soil pH. Organically-bound Cu was highly correlated with total recoverable Cu, increasing significantly with external Cu loads, and decreasing with soil pH . Lime addition converted part of the Cu from available pools to more stable forms. Organically-bound Cu complexes dominated in soil solution, surface runoff, bulk soils, and particulates. Biochar was effective in Cu immobilization, thus reducing Cu loss potential by leaching. Biochar application rate was negatively correlated with concentrations of P, Ca, Mg, Zn, Mn, and NH4-N in leachate but positively correlated with concentrations of K and Na. Decreased free Cu2+ ion activity accompanied by increased organically-bound Cu activity with a negative oil contamination by copper (Cu) is a worldwide concern, especially in South Florida where Cu-based fungicides have been extensively used in agriculture. In this study, laboratory incubation, chemical characterization, speciation, and column leaching were conducted to evaluate lime and biochar as potential amendments for remediation of Cu-contaminated soils. Soil available Cu estimated by CaCl2, NH4OAc, or Mehlich-3 extraction significantly increased with external Cu loads and decreased with soil pH. Organically-bound Cu was highly correlated with total recoverable Cu, increasing significantly with external Cu loads, and decreasing with soil pH . Lime addition converted part of the Cu from available pools to more stable forms. Organically-bound Cu complexes dominated in soil solution, surface runoff, bulk soils, and particulates. Biochar was effective in Cu immobilization, thus reducing Cu loss potential by leaching. Biochar application rate was negatively correlated with concentrations of P, Ca, Mg, Zn, Mn, and NH4-N in leachate but positively correlated with concentrations of K and Na. Decreased free Cu2+ ion activity accompanied by increased organically-bound Cu activity with a negative correlation between DOC and Cu concentration were observed for leachates. These results suggest possible conversion of Cu from available pool to more stable forms by biochar addition. Biochar amendment resulted in lower >0.45and higher .45µm solids concentration and in reduced fractional volume of nanoparticles in leachate. Fourier transforms infrared spectroscopy analyses provided direct evidence of Cu-organic complexation, which is one of the mechanisms for biochar to bind heavy metals in contaminated soils. A protocol was developed for separating and characterizing nanoparticles from soils with contrasting properties. Standard centrifuge regimen combined with dynamic light scattering (DLS) was a reliable method. Bi-and tri-parameter models were used to describe size distribution of particles in suspension. Re-aggregation occurred at high separation energy only in clayey soils rich in hematite, which can be distinguished by DLS and other routine analytical protocols. The newly developed protocol should be applicable to other environmental samples such as sediments and storm waters.
General Note:
In the series University of Florida Digital Collections.
General Note:
Includes vita.
Bibliography:
Includes bibliographical references.
Source of Description:
Description based on online resource; title from PDF title page.
Source of Description:
This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility:
by Santanu Bakshi.
Thesis:
Thesis (Ph.D.)--University of Florida, 2013.
Local:
Adviser: HE,ZHENLI.
Local:
Co-adviser: HARRIS,WILLIE G,JR.
Electronic Access:
RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2014-12-31

Record Information

Source Institution:
UFRGP
Rights Management:
Applicable rights reserved.
Classification:
lcc - LD1780 2013
System ID:
UFE0046295:00001