The Use of Expanded Perlite for Pb(II) removal from Industrial Leachate: Kinetic Studies

Abstract

In this study, the removal efficiency of Pb(II) from industrial leachate was investigated by using expanded perlite by adsorption. The effects of pH, contact time, and adsorbent dosage were examined on the Pb(II) removal. The adsorption kinetics were tested to understand the adsorption mechanism using three kinetic models, i.e., Elovich, intraparticle diffusion, and the pseudo second order reaction kinetic models. As the result, the best conformity kinetic model for Pb(II) adsorption on expanded perlite was described as the pseudo second-order (R2>0.99). It is indicated that chemisorption is the determining step of adsorption process rather than mass transfer from industrial leachate. According to the data obtained from intraparticle diffusion model, the adsorption is composed of more than one step. This can be attributed to the fact that the adsorption in the final portion was the intraparticle diffusion while the adsorption in the first portion was the film diffusion. Both film diffusion and intraparticle diffusion processes in the adsorption of Pb(II) on expanded perlite are significant. This study indicated that expanded perlite was an influential alternative adsorbent for the removal of Pb(II) by adsorption from industrial leachate.