OXIDATIVE DEHYDROGENATION OF ETHYLBENZENE TO STYRENE OVER CARBON-BASED CATALYSTS

Catalysts based on pyrolyzed polymeric systems and high surface area carbons have been investigated for their activity in the oxidative dehydrogenation of ethylbenzene to styrene. A relationship between surface area and activity is established, with high surface area materials displaying greater activity. One material in particular, ultrahigh surface area carbon molecular sieves, exhibits extraordinary reactivity-80% conversion with over 90% selectivity to styrene in a single pass at 350 °C. This is more active than recently reported inorganic oxide-based catalysts at a significantly lower temperature. The results are consistent with the proposal that the carbonaceous overlayer observed in many inorganic oxide systems is the true catalyst, and that the surface structure of this carbon is the key to the catalytic activity. © 1990.