Solution to the homogeneous surface diffusion model for batch adsorption systems using orthogonal collocation

A solution to the homogeneous surface diffusion model has been developed an d incorporated into a batch adsorption model based on external boundary lay er mass transport and homogeneous diffusion. The model has been extensively tested using three experimental adsorption systems, namely phenol on carbo n, basic yellow dye on carbon and basic blue dye on silica. The effect of i nitial solute concentration and adsorbent mass has been studied in 23 batch experiments, which have been modelled using the collocation solution metho d to solve the homogeneous surface diffusion equation. The theoretical conc entration decay curves show a high degree of correlation with experimental data. (C) 2001 Elsevier Science B.V. All rights reserved.