Influence of Chromium in Cr/Zn-Bea Metal–Zeolite Composites on Their Acid–Base Characteristics and Catalytic Properties in the Processes of Propane Dehydrogenation

According to the quasi-equilibrium NH₃ and CO₂ thermal desorption data, the effect of chromium in the composition of zinc-containing BEA zeolites with different Si/Al ratios on their acid–base characteristics and catalytic properties in the process of dehydrogenation of propane to propene with or without CO₂ has been determined. A positive effect on the propane conversion and the propene selectivity is found for a catalyst based on the initial Cr/ZnAlBEA zeolite (Si/Al = 17). Higher propane conversion is achieved in the process of propane dehydrogenation with the participation of CO₂ in the presence of Cr/Zn-BEA catalysts, but with lower propene selectivity when compared to the propane dehydrogenation process without CO₂.