Isotherm modelling, kinetic study and optimization of batch parameters using response surface methodology for effective removal of Cr(VI) using fungal biomass

• Published in: PloS one Vol. 10; no. 3; p. e0116884
• Main Authors: S, Melvin Samuel, M, Evy Alice Abigail, Chidambaram, Ramalingam
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 18.03.2015; Public Library of Science (PLoS)
• Subjects: Activated carbon; Adsorbents; Adsorption; Aspergillus niger; Aspergillus niger - growth & development; Biomass; Biosorption; Cancer; Carbonyl groups; Carbonyls; Chemisorption; Chromium; Chromium - metabolism; Design parameters; Effluents; Environmental conditions; Experimental design; Experiments; Fourier transforms; Functional groups; Fungi; Heavy metals; Hydrogen-Ion Concentration; Industrial effluents; Isotherms; Kinetics; Models, Biological; Optimization; Process parameters; Response surface methodology; Scientometrics; Soil contamination; Temperature effects; Waste Water - microbiology; Water Purification - methods; India
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0116884

Biosorption is a promising alternative method to replace the existing conventional technique for Cr(VI) removal from the industrial effluent. In the present experimental design, the removal of Cr(VI) from the aqueous solution was studied by Aspergillus niger MSR4 under different environmental conditions in the batch systems. The optimum conditions of biosorption were determined by investigating pH (2.0) and temperature (27°C). The effects of parameters such as biomass dosage (g/L), initial Cr(VI) concentration (mg/L) and contact time (min) on Cr(VI) biosorption were analyzed using a three parameter Box-Behnken design (BBD). The experimental data well fitted to the Langmuir isotherm, in comparison to the other isotherm models tested. The results of the D-R isotherm model suggested that a chemical ion-exchange mechanism was involved in the biosorption process. The biosorption process followed the pseudo-second-order kinetic model, which indicates that the rate limiting step is chemisorption process. Fourier transform infrared (FT-IR) spectroscopic studies revealed the possible involvement of functional groups, such as hydroxyl, carboxyl, amino and carbonyl group in the biosorption process. The thermodynamic parameters for Cr(VI) biosorption were also calculated, and the negative ∆Gº values indicated the spontaneous nature of biosorption process.