Catalytic oxidation of olefin over oxide catalysts containing molybdenum: III. Oxidation of olefin to ketone over Co 3O 4MoO 3 and SnO 2MoO 3 catalysts

Abstract

Oxidation of various olefins and some related hydrocarbons over Co 3O 4MoO 3 and SnO 2MoO 3 (Co or Sn:Mo = 9:1) are described. Both binary oxides are effective catalysts for the oxidation of olefins to corresponding ketones, while SnO 2MoO 3 is the better one. Propylene is converted to acetone at 100–160 °C with more than 90% selectivity over SnO 2MoO 3. n-Butenes and 1-pentene are oxidized to methyl ethyl ketone and methyl propyl ketone (including diethyl ketone), respectively. However, ethylene is converted exclusively to carbon dioxide. Isobutene, which has no corresponding ketone, is converted to t-butyl alcohol and diisobutene over SnO 2MoO 3 and to α-methyl acrolein over Co 3O 4MoO 3. On the other hand, primary and secondary alcohols are easily oxidized to corresponding aldehyde and ketone, respectively, over both catalysts. The ketone formation is concluded to proceed via oxyde-hydrogenation of alcohol or alcoholic intermediate formed by hydration of olefin. The active site seems to involve an acidic point which is formed by the combination of tin or cobalt oxide with molybdenum trioxide.