Theoretical eht study of propene adsorption on model clusters of first series transition metal oxides and MgO

Abstract

On the basis of Extended Hückel Theory, empirical studies on the adsorption step involved in the selective oxidation of propene are presented. Investigations have been made of the interaction between linear clusters of some transition metal oxides (Cu +, Cu 2+ Fe 2+, Co 2+, Ni 2+, Zn 2+, a test oxide (Mg 2+) and a propene molecule. The results obtained agree qualitatively with the experimental data for the two inactive oxides and the more active and non-selective oxides, and seem to confirm that the first step in the mechanism consists of a proton transfer rather than a hydrogen-transfer reaction for the Cu 2O and CuO catalysts. The calculated barrier heights involved in the transfer of a proton from the propene molecule to a cluster are of the same order of magnitude as the experimentally determined activation energies.