ON THE PARTIAL OXIDATION OF PROPANE AND PROPYLENE ON MIXED-METAL OXIDE CATALYSTS

The present review analyses the literature data reported on the partia l oxidation of propane to organic compounds (acrolein, acrylic acid an d acrylonitrile) over mixed metal oxides, mainly magnesium vanadates, vanadia bismuth molybdates and vanadia antimony. The data were compare d to those reported on the partial oxidation of propylene over bismuth molybdate and antimony-tin multicomponent oxides and over cuprous sim ple oxide. For both reactions, we analyzed the involved reaction mecha nisms, intermediate species, active phases and active sites. The role of water produced during the reaction and that of the Bronsted acid si tes were shown to be important in the determination of the selectivity of the expected products. The main conclusion of our study is that a good mix of acid-base and redox properties of the oxide surface should permit a controlled orientation of the reaction towards selective pro ducts.