Removal of Heavy Metals from Aqueous Solution by Adsorption on Biomass Based Adsorbent

Abstract

Abstract Removal of heavy metals i.e. Zn 2+ and Cd 2+ from aqueous solution by adsorption onto biomass based adsorbent was investigated as a function of time and different concentrations. The sample was characterized by FTIR, EDS, BET surface area and Zeta potential technique, which was reported earlier. Adsorption kinetics of Zn 2+ and Cd 2+ was tested by first order kinetics, Elovich and parabolic diffusion kinetic equations which show that the process of adsorption is diffusion controlled process. The rate of adsorption was high at high adsorption temperature. Thermodynamic parameters like Δ H° , Δ S° and Δ G° were calculated from the kinetic data. The negative value of Gibbs free energy (Δ G °) shows the spontaneous nature of the process. Freundlich, Langmuir, Temkin isotherms and distribution coefficient were found fit to the adsorption isotherm data.