XAFS characterization of supported PdCl2-CuCl2 catalysts for co oxidation

Abstract

A heterogenized Wacker catalyst system in which pores of a high surface area alumina were filled with an aqueous solution of PdCl2-CuCl2 was active for the oxidation of CO near room temperature. The structure of the catalyst was studied by XRD and XAFS. The active phase of Pd was a molecular Pd species whose structure was similar to PdCl2, probably modified by a carbonyl ligand. The active phase of copper was found to be solid Cu2Cl(OH)(3) particles. The presence of Cu was essential to keep the Pd in the Pd(II) state during the reaction.