Evaluation of the mechanism of the oxy-dehydrogenation of propane over manganese oxide Original Research Article

The oxidation of propane over a Mn3O4 catalyst has been investigated with oxygen to propane ratios up to 2:1. High selectivities to the oxy-dehydrogenation product propene have been obtained at low conversions, with yields up to 5% and productivities up to above 1.5 KgC3H6/Kgcat h. Data on the mechanism and on the reaction pathways have been derived from an evaluation of the reaction kinetics and from FT-IR experiments. The main by-reaction with respect to oxy-dehydrogenation is propene over-oxidation to CO2. Direct total oxidation of propane to CO2 can become predominant only in oxygen excess. Isopropoxide species act probably as surface intermediate species in propene synthesis.