A mathematical model was developed to evaluate the influence of structural and operational factors on convective desorption processes (desorption of a liquid from capillary-porous material). The possibility to utilize this model for the case of water desorption from the polystyrene cation resin CG-8 is presented. The model accounts for unsteady one-dimensional simultaneous heat and mass transfer between the gas (humid air) and the solid phase (CG-8 resin). The identification of effective transport properties for the considered packed bed of material (CG-8 resin) is discussed. To this purpose, data from the literature are used.