Аннотация:The effect that introduction of cerium oxide into oxide systems based on chromium and silicon exerts on the catalytic properties of these systems in nonoxidative propane dehydrogenation in a flow-through system with a fixed catalyst bed was studied. The characteristics of the catalysts CrOx–SiO2 and CrOx–CeO2–SiO2, both containing 9 wt % CrOx assuming the Cr2O3 stoichiometry, were compared. The СеО2 content of the ternary system was 52 wt %. The catalysts were characterized by X-ray diffraction analysis, scanning electron microscopy, Raman spectroscopy, electron paramagnetic resonance, X-ray photoelectron spectroscopy, temperature-programmed reduction with hydrogen, and thermal analysis. In the initial period of the reaction, the catalyst containing CeO2 demonstrated higher propane conversion at 500 and 550°С and higher deactivation rate compared to CrOx–SiO2. Both catalysts can be regenerated by treatment in an air stream at 550°С for 30 min. Cerium dioxide favors the reduction of chromium in high oxidation states to form active reaction sites, Cr3+ ions, ensures higher dispersity of the chromium oxides, and favors partial oxidation of coke deposits in the initial period of the catalyst operation.
