Gas Phase Oxidation of Benzene to Phenol using Pd/Cu Salt Catalysts: Effect of Counter Anion in Copper Salts

The catalyst, Pd, Cu 3 (PO 4 )/SiO 2 , impregnated by H 3 PO 4 exhibits a powerful activity for the title reaction. The rate of phenol production obtained is 0.5mmol(h g-cat) −1 that is about ten times higher than that obtained with the Pd, CuSO 4 /SiO 2 catalyst studied previously. The improvement of the catalyst activity may be ascribed to the presence of a liquid film of phosphoric acid over the silica surface.