EXAFS study of Pd/Sibunit and Pd–Ga/Sibunit catalysts for liquid-phase hydrogenation of acetylene to ethylene

Abstract

A series of catalysts Pd/Sibunit and Pd–Ga/Sibunit were prepared by impregnation with joint solutions of palladium and gallium nitrates in ethanol. The state of the active component and catalytic properties of the samples were studied in the liquid-phase hydrogenation of acetylene. The EXAFS method showed that the active component in the gallium-modified catalysts exists in the form of a non-stoichiometric Pd–Ga solid solution. The activity of the catalysts was found to be determined by the ratio Pd:Ga. It was shown that at the molar ratios Ga:Pd>0.5:1, the catalytic activity is reduced by blocking the surface of the bimetallic particles by gallium oxide.