Attention is focused on the effect of the heat of adsorption and of the radial maldistribution on the toluene adsorption on activated carbon in a fixed-bed adsorber. A two-dimensional (2D), non-equilibrium, non-isothermal model is proposed to describe the heat and mass transfer. The influence of maldistribution on the local gas concentration, the toluene loading and the temperature in the adsorber are shown. Taking the effect of the heat of adsorption and the effect of maldistribution into account the predicted sorption behavior is in good agreement with the experimental results. For practical use the influence of adsorption hear on the adsorption is negligible at low concentrations.