Oxidative dehydrogenation of propane over supported chromium-molybdenum oxides catalysts

Abstract

Catalytic oxidative dehydrogenation of propane to propylene was studied on alumina-supported chromium-molybdenum oxides catalysts - 10 wt% Cr xMo(1-x)/γ-Al2O3 (where x=0-1). The catalysts are active for the reaction. Increase in the amount of molybdenum in the catalysts decreases the reducibility and changes the nature of the lattice oxygen in the catalyst as indicated by TPR and XPS data. The catalysts with lower reducibilities exhibits corresponding increase in the propylene selectivities. Alkali metals (Li, K, Cs)-doped 10 wt% Cr 0.8Mo0.2 (alkali/CrMo weight ratio of 0-0.175), shows maxima in both propane degrees of conversion and propylene yields in the ratio ranges explored. One of the catalysts (Cs/CrMo=0.125) exhibits propane conversion of 15.1% and selectivity to propylene of 64.5% at 420 °C. This is among the most promising catalysts reported for oxidative dehydrogenation of propane. © 2003 Elsevier B.V. All rights reserved.