Toluene vapor was adsorbed in a laboratory-scale packed-bed adsorber using granular activated carbon (GAC) at constant pressure (101.3 kpa). The adsorber was operated batchwise with the charge of GAC in the range of 2-4 g to obtain the breakthrough curves of toluene vapor. Experiments were carried out at different adsorption temperatures (25-50 degrees C), sparger temperatures (20-30 degrees C), and the flow rates of nitrogen (80-150 cm(3)/min) to investigate the effects of these experimental variables on the breakthrough curves. The deactivation model was tested for these curves by combining the adsorption of toluene vapor and the deactivation of adsorbent particles. The observed values of the adsorption rate constant and the deactivation rate constant were evaluated through analysis of the experimental breakthrough data using a nonlinear least squares technique. The experimental breakthrough data were fitted very well to the deactivation model than the adsorption isotherm models in the literature.