Kinetics, Equilibrium, and Comparision of Multistage Batch Adsorber Design Models for Biosorbent Dose in Metal Removal from Wastewater

Kinetics of lead(II) adsorption onto increasing masses of raw and Ca(OH)(2)-treated pine cone powder was evaluated. The first rapid stage in the adsorption profile was found to be controlled by film and intraparticle diffusion while the second slow stage was influenced by slow movement of lead(II) through longer diffusion paths created by particle aggregation especially at higher dose. Slight changes in surface properties due to base activation was observed which lead to greater contribution of the diffusion processes to the rate-controlling step. On the basis of the Langmuir isotherm, three multistage batch adsorber models were compared.