At the Department of Chemical Technology of the Budapest TU several models were developed for the simulation of multicomponent sorption processes in packed columns. The goal of this research is to investigate the accuracy and reliability of various models, describing mass transfer processes, to investigate various effects in packed beds (axial dispersion, radial velocity distribution, concentration dependence of the diffusion coefficients, etc.) and to find effective solution methods for coupled partial differential equations by finite difference techniques. Now we present one of these models.