Fluidized-Bed Reactor for the Intensification of Gas-Phase Photocatalytic Oxidative Dehydrogenation of Cyclohexane

The behavior of a two-dimensional laboratory-scale fluidized-bed catalytic reactor for the photocatalytic oxidative dehydrogenation of cyclohexane to benzene has been studied, employing a molybdenum-based catalyst and a titania-alumina mixed oxide as a support. A preliminary mathematical model is proposed for the evaluation of the effect of the main factors that affect the overall reactor performances. Experimental data evinced that the reaction rate is not dependent on the oxygen concentration; instead, it depends on cyclohexane concentration, according to Langmuir-Hinshelwood (LH)-type kinetics. Taking into account that the interaction between photoexcited molybdate and adsorbed cyclohexane is the rate-limiting step, the functionality in light intensity was found. The mathematical model describes the performance of the photocatalytic fluidized-bed reactor well for all operating conditions examined.