In this work, experimental breakthrough curves for sulfur dioxide adsorption on silica gel were analysed with deactivation models proposed by 'Can. J. Chem. Eng. 60 (1982) 314' and 'Ind. Eng. Chem. Res. 40 (2001) 5206'. The deactivation model of 'Ind. Eng. Chem. Res. 40 (2001) 5206' taking into account the concentration dependence of the deactivation process along the reactor gave the best fit to the experimental breakthrough data for sulfur dioxide adsorption on silica gel. Deactivation rate constant k(d) values were determined from adsorption experiments done at 473 K temperature with a sulfur dioxide inlet concentration in the range of 0.0443-0.3504 mol/m(3). (C) 2002 Elsevier Science Ltd. All rights reserved.