The deactivation data obtained from the multiple regeneration of platinum-containing catalysts were utilized to explore the efficiency of reforming catalyst utilization. The data were collected in a CSTR at a total pressure of 101.325 kPa and W/F values up to 0.33 g min/cm(3). The reactive system investigated was the re-forming and coking of n-octane and methylcyclopentane on the monometallic Pt/Al2O3 and the bimetallic Pt-Re/Al-2 O-3 catalysts. The deactivation models combined the kinetic equation with the coking equation; both of these equations were derived from mechanistic models. The kinetic expressions were based on the models of Susu et al. for n-octane reaction and Dartingues et al. for methylcyclopentane reaction. The coking mechanism of Corella and Asua was used for the coking reaction. The coupling of the two models resulted in a dynamic expression, and the parameter estimates were carried out without decoupling the main reaction from the coking reaction. The model formulation affords the estimation of the level of residual activity by the incorporation of a factor, f, representing incomplete deactivation. A high value of f was obtained for all deactivation-kinetic data indicating high utilization efficiency for the catalysts for the two reactants, regardless of the large difference in the coking ability of the hydrocarbon species.