| abstract |
Oxidative dehydrogenation catalysts suitable for converting C4 to C8 mono-olefins to conjugated dienes comprise vanadium, phosphorus, and alkali metal components, and preferably also a tin component, in combination with a microporous crystalline silica or a crystalline zeolite having a silica-to-alumina ratio of at least 6.0. In one embodiment, the catalyst has a surface area between 30 M2/g to 450 M2/g and the vanadium has an average valence in the range of from 3.50 to 4.95. |