Prediction of binary systems for kinetics of batch adsorption using basic dyes onto activated carbon

The present work develops the film-homogeneous diffusion model for multicomponent batch adsorption and applies to it two binary mixtures of basic dyes, namely (Basic Red 22 + Basic Yellow 21) and (Basic Red 22 + Basic Blue 69), onto activated carbon F400. The adsorption rate of each component j is measured by the external mass transfer coefficient k_fj and intraparticle solid diffusivity D_sj. A single k_fj has succeeded to describe the whole experimental range of each component while D_sj has increased exponentially with the initial sorbate concentration C_oj. Equilibrium has been successfully described by the empirically extended Freundlich isotherm.