Mesoporous silica-supported chromium catalyst: Characterization and excellent performance in dehydrogenation of propane to propylene with carbon dioxide

Nonordered mesoporous molecular sieves MSU-x supported chromium catalysts (Cr/MSU-x) were prepared and characterized with X-ray diffraction, diffuse reflectance UV–vis, and H2-temperature programmed reduction techniques. Excellent results in dehydrogenation of propane to propylene with carbon dioxide (CO2) over Cr/MSU-x, 36.8% of propane conversion with 89.1% of propylene selectivity, were obtained. Lower Cr loading results in formation of Cr species with higher oxidation state, whereas higher Cr loading leads to bulk chromium oxide (Cr2O3) crystal on catalyst surface. The active sites of the catalysts and the promoting effect of mesoporous MSU-x as support were also discussed.