Removal of Ni2+ from aqueous solution by rice bran

Rice bran, an agricultural by-product, was used for the sorptive removal of Ni2+ from aqueous solutions. Batch adsorption experiments were performed as a function of initial concentrations, contact time, pH and temperature. The experimental data were analysed by Langmuir, Freundlich and Redlich-Peterson isotherms. The equilibrium sorption capacity of Ni2+ Was determined from the Langmuir equation and was found to be 28.36 mg/g. The sorption process follows pseudo-second-order kinetics. The thermodynamic parameters, such as Delta G and Delta S, have been calculated. The thermodynamics of Ni2+/rice bran system indicates the spontaneous nature of the process.