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Document Type:Latin Dissertation
Language of Document:English
Record Number:53198
Doc. No:TL23152
Call number:‭MR20227‬
Main Entry:Deepa Prabhu Mungasavalli
Title & Author:Removal of chromium from aqueous solutions by fungus Aspergillus nigerDeepa Prabhu Mungasavalli
College:The University of Regina (Canada)
Date:2006
Degree:M.A.Sc.
student score:2006
Page No:118
Abstract:Fungal biosorption is an emerging field for metal sequestering as biomasses have proven to be effective for metal biosorption from aqueous study involved an investigation of the use of Aspergillus niger biomass for the removal of chromium from aqueous solutions. Pretreatment of A. niger biomass improved the biosorption capacity of A. niger biomass and cetyl trimethyl ammonium bromide (CTAB) pretreatment exhibited maximum chromium removal. A full factorial design of experiments was conducted to determine the major factors affecting the biosorption of chromium by CTAB pretreated biomass. Further experiments focused on the important factors such as pH, temperature, and biomass mass. The kinetics of biosorption of chromium was found to follow Ho pseudo-second order reaction at an optimum pH of 3.0 and equilibrium time of 2 h. Isotherm studies conducted at 5 ± 2 °C, 15 ± 2 °C, 22 ± 2 °C, and 30 ± 2 °C provided maximum biosorption capacities of 14.5 mg/g, 15.2 mg/g, 10.6 mg/g, and 11.6 mg/g, respectively. Both the Langmuir and Freundlich isotherm models were found to describe biosorption. The thermodynamics of adsorption indicated that the biosorption reaction was spontaneous and exothermic in nature. Physical adsorption and chemisorption were found to be involved in the biosorption of chromium. NaOH was found to be an effective elutant, with 90% desorption. A column study showed that polysulfone immobilized CTAB pretreated biomass was less effective in removing chromium when compared with the batch studies. Fourier transform infrared spectroscopy analysis indicated that amino groups on the fungal cell wall contributed in the biosorption process.
Subject:Health and environmental sciences; Applied sciences; Environmental science; Environmental engineering; 0768:Environmental science; 0775:Environmental engineering
Added Entry:The University of Regina (Canada)