Effect of adding Mo to Fe-Ce-K mixed oxide catalyst on ethylbenzene dehydrogenation

Abstract

The effect of adding Mo in the low K range of composition of Fe-Ce-K and Fe-Ce-Mo-K mixed-oxide catalysts on dehydrogenation of ethylbenzene was studied. Fe-Ce-K formed considerable amounts of by-products in the low K range. Addition of Mo not only made the catalyst inactive in the low K range, but also prevented the formation of by-products because adding Mo decreased the surface area considerably in the low K range. X-ray diffraction (XRD) showed Mo formed three molybdates (K2MoO4, KCe(MoO4) 2, and Fe2(MoO4)3), which were inactive for the reaction. Therefore, the effect of adding Mo resulted from the formation of molybdates on the surface, which covered the active sites for by-product formation.