Oxidative dehydrogenation of ethane by carbon dioxide over sulfate-modified Cr2O3/SiO2 catalysts

The oxidative dehydrogenation of ethane into ethylene by carbon dioxide ove r unsupported Cr2O3, Cr2O3/SiO2 and a series of Cr2O3/SiO2 catalysts modifi ed by sulfate was investigated. The results show that Cr2O3/SiO2 is an effe ctive catalyst for dehydrogenation of ethane and CO2 in the feed promotes t he catalytic activity. Sulfation of silica will influence the catalytic beh avior of Cr2O3/SiO2 in dehydrogenation of ethane with carbon dioxide depend ing on the amount of sulfate. Cr2O3/6 wt% SO42--SiO2 catalysts exhibit an e xcellent performance for this reaction, giving an ethylene yield of 55% at 67% ethane conversion at 650(degrees)C. Characterizations indicate that add ition of sulfate changes the bulk and surface properties of Cr2O3/SiO2, pro moting the reduction of Cr6+ to Cr3+ and favoring the catalytic conversion.