Kinetic Features of Cumene Dehydrogenation over Porous Catalytic Converters

The kinetics of cumene dehydrogenation in the channels of porous ceramic converters modified with tungsten oxide were investigated. It was shown that, under the reaction conditions studied, this process occurs far from thermodynamic equilibrium in an open system and follows a first-order kinetic equation with respect to cumene. Based on the effective activation energy (161 kJ/mol) and an analysis of the reaction rate–temperature relationship, a stepwise sequence of surface dehydrogenation reactions over WO3 is proposed: adsorption of cumene on W6+ acid sites, hydrogen abstraction leading to the formation of metastable carbenium ions, and hydrogen recombination on the catalyst surface. The resulting activation energy and pre-exponential factor (1.85 × 108) are consistent with values previously reported for the dehydrogenation of alkylbenzenes over oxide catalysts, thereby supporting the validity of the proposed kinetic model.