BIOSORPTION STUDY OF CR(VI) FROM AQUEOUS SOLUTIONS BY RICE BRAN AND WHEAT BRAN

This paper reports the research findings of a laboratory-based study on the removal of Cr(VI) from aqueous solution using rice bran and wheat bran as biosorbents.The effects of various parameters like contact time,initial concentrations,sorbent dose,pH and particle size were investigated.Cr(VI) removal was found to be maximum at pH1.0.The amount of Cr(VI) adsorbed increased with decreasing RB'particle size and increasing WB' particle size.The Langmuir and Freundlich adsorption models were used to represent the experimental data and equilibrium data fitted well to Freundlich and Langmuir isotherm model for RB and WB,respectively.Pseudo-second-order model was found to explain the kinetics of Cr(VI) adsorption most effectively.The thermodynamic parameters indicated that the adsorption reaction is endothermic and spontaneous.The results showed that rice bran and wheat bran are suitable for development of efficient biosorbents for the removal of Cr(VI) from wastewater,furthermore wheat bran is better.