Js. Chang et al., Effect of carbon dioxide in dehydrogenation of ethylbenzene to styrene over zeolite-supported iron oxide catalyst, B KOR CHEM, 19(12), 1998, pp. 1342-1346
The dehydrogenation of ethylbenzene with carbon dioxide has been carried ou
t over ZSM-5 zeolite-supported iron oxide catalyst as well as commercial ca
talyst (K-Fe2O3) and unsupported iron oxide (Fe3O4) for comparison. In the
dehydrogenation over the ZSM-5 zeolite-supported iron oxide catalyst, ethyl
benzene is predominantly converted to styrene by an oxidative pathway in th
e presence of excess carbon dioxide. Carbon dioxide in this reaction is fou
nd to play a role as an oxidant for promoting catalytic activity as well as
coke resistance of catalyst. On the other hand, both of commercial catalys
t and unsupported Fe3O4 exhibit considerable decrease in catalytic activity
under the same condition. It is suggested that an active phase for the deh
ydrogenation with carbon dioxide over ZSM-5 zeolite-supported iron oxide ca
talyst would be rather a reduced and isolated magnetite (Fe3O4)-like phase
having oxygen deficiency in the zeolite matrix.