Dehydrogenation of ethylbenzene to styrene in the presence of CO2

The relationship between the yield of styrene and the energy required for s eparation by the model distillation system clearly indicates that it is pos sible to save energy by a new process using CO2, An Fe2O3(10 wt%)-Al2O3(90 wt%) catalyst prepared by a coprecipitation metho d was found to be effective for dehydrogenation of ethylbenzene to produce styrene in the presence of CO2, instead of the steam used in commercial pro cesses. The dehydrogenation of ethylbenzene over the catalyst in the presen ce of CO2 was considered to proceed both via 45% of a one-step pathway and via 55% of a two-step pathway. CO2 was found to suppress the deactivation o f the catalyst during the dehydrogenation of ethylbenzene. Copyright (C) 20 00 John Wiley & Sons, Ltd.