Oxygen spillover for the design of industrial oxidation catalysts

Abstract

The importance of the oxygen spillover for the design of effective oxidation catalysts is demonstrated by the review of our continuous investigations using 18 O tracer in the oxidation of propylene over multicomponent metal oxide catalysts. The oxygen spillover different from the hydrogen takes place exclusively through the bulk diffusion of oxide ion, which is remarkably accelerated by the formation of lattice vacancies. It is suggested that the most effective catalyst system should have multifunctional nature to promote the activation of oxygen and migration of active oxygen species as well as the selective reaction between adsorbed propylene and active oxygen species. Collaboration of different kinds of active site through the oxygen spillover enhances not only the catalytic activity and selectivity but also the stability of the catalyst system.