Modeling of Cd2+ sorption kinetics from aqueous solutions onto some thiolated agricultural waste adsorbents

Batch kinetic studies was conducted to determine the influence of contact time and chemical modification of adsorbent on sorption of Cd2+. Results indicate that maximum removal efficiencies of 54.66% and 58.66% was obtained for 0.5 and 1.0 MCF at the end of 30 min. Analysis of kinetic models applied to the sorption of Cd (II) ions on the adsorbents was evaluated for the pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion, mass transfer and intra-particle diffusivity models, respectively. The results indicate that the pseudo-second order kinetic model was found to correlate best with the experimental data with rate constants of 2.34×10-1 and 4.64×10-1g mg-1 min-1 for 0.5 and 1.0 MCF, respectively. © 2006 Asian Network for Scientific Information.