Catalytic behaviour of chromium oxide supported on CMK-3 carbon replica in the dehydrogenation propane to propene

Abstract

Ordered mesoporous carbons (CMK-3) were prepared by structure replication of mesoporous SBA-15 using sucrose as a carbon source. Based on this mesoporous carbon support a series of Cr/CMK-3 catalysts with a Cr loading varying in the range of 1–40wt.% of Cr2O3 were prepared by the impregnation method. Both the silica support and the carbon catalysts were characterized by means of low-temperature N2 sorption, XRD, H2-TPR, XPS and TGA. The catalytic performance of Cr/CMK-3 catalysts was tested in the dehydrogenation of propane. The conversion of propane increased with raising the chromium content up to 20wt.% of Cr2O3. It was also found that the oxidation state of Cr in the studied catalysts slightly depended on the Cr loading. In all fresh samples, amorphous Cr(III) species predominated. However, alpha-Cr2O3 and traces of Cr(VI) species were found for the Cr/CMK-3 catalysts samples with a relatively high Cr content.