The adsorption of single and binary mixtures of anionic dyes through an ion-exchange membrane adsorber was analyzed experimentally and theoretically. A generalized model to simulate the dynamic adsorption of multi-component mixtures is put forward. The model is based on the continuity equation, which describes the convection flow through the membrane, the axial dispersion and adsorption on the membrane adsorber and the extended Langmuir isotherm, to explain the competitive adsorption between solutes. The experimental breakthrough curves of the two dyes in binary mixtures were simulated with the parameters of the model determined from the experiments of the single dyes. The dyes were separated on the basis of their different adsorption characteristics. (C) 2010 Elsevier B.V. All rights reserved.