Kinetic Study On The Adsorption Of Dyes Onto Activated Carbon

Abstract

Four batch systems were applied to study the adsorption of methylene blue, methyl orange, crystal violet and rhodamine B from aqueous solution by activated carbon. The kinetics of adsorption systems were evaluated by pseudo-first-order and modified pseudo-first-order models. Kinetics of dye adsorption on activated carbon has been studied at close to equilibrium condition. By empirical kinetic data, it was shown that application of the PFO and MPFO equations for modeling over the entire span of adsorption time causes big error near initial time of adsorption. Comparison between the pseudo-first-order and the modified pseudo-first-order models has been provided. It was shown that adsorption data of the system dyes/AC proceeded in two steps; an initial step governed by the intra-particle diffusion model, followed by PFO or MPFO models.