Propane oxidative dehydrogenation over chromium oxide-based catalysts

Supported chromium oxide catalysts have been tested and found to be active in propane oxidative dehydrogenation (POD). The effects of various supports (gamma-Al2O3, TiO2, SiO2, and MgO) and feed compositions were investigated. On the 10 wt.% chromium oxide on alumina, the propane degree of conversion was 16.7% and the selectivity to C3H6 was 54.1% at 450degreesC. A sample of the catalysts was characterized using BET, XPS, and temperature-programmed reduction (TPR) techniques. A kinetics study was also performed on the catalyst. The rates of propane consumption and propylene productions were found to depend strongly on the oxygen partial pressures. Langmuir and redial-type rate expression were tested; the latter was found to give a better fit for the rate data. A model for the reaction was proposed. (C) 2004 Elsevier B.V. All rights reserved.