Selectivity in the oxidative dehydrogenation of butene on zinc-iron oxide catalyst

The oxidative dehydrogenation of butene to butadiene was studied on a zinc ferrite catalyst. Room temperature adsorption of butene on the catalyst followed by thermal desorption resulted in the production of butene isomers, butadiene, and carbon dioxide. Evidence was presented which suggests that the selective oxidation and the combustion sites are independent, and this made possible the estimation of the densities of these two oxidation sites from the amounts of oxidation products formed. Information on the reactivities of the sities was provided by temperature programmed desorption profiles of butene. Comparison of these results with those on iron oxide suggests that zinc ferrite is a more selective oxidation catalyst because it has a higher density of selective oxidation sites and a lower density of combustion sites, and because its combustion sites are less active than those on iron oxide.