Activities of ion-exchange resin catalysts, having different hydrogen exchange capacities ranging between 5.1 and 1.3 meq H+/g, on the etherification reactions of 2M1B (2-methyl-1-butene) and 2M2B (2-methyl-2-butene) with ethanol were experimentally tested in a fixed bed reactor. These catalysts were prepared by the heat treatment of Amberlyst-15 catalysts at 220 degreesC at different durations of time and also by the synthesis of sulfonated styrene divinyl benzene cross-linked resins. Activity of these catalysts in the production of TAEE from 2M2B showed an almost linear increase with an increase in hydrogen ion-exchange capacity of the catalysts. However, the effect of hydrogen ion-exchange capacity of the catalyst on the observed rate became insignificant over a hydrogen ion-exchange capacity of 2.8 meq H+/g, in the case of using 2M1B as the reactant in the production of TAEE. This was explained by the strong influence of diffusion resistance on the reaction rate in the case of using 2M1B as the reactant, which was much more reactive than 2M2B in the production of TAEE. (C) 2004 Elsevier B.V. All rights reserved.