Platinum and palladium on silica produced by impregnation from tetrakis(triphenylphosphine) complexes

Abstract Platinum and palladium supported on silica have been obtained by the heat treatment of Pt [P(C 6 H 5 ) 3 ] 4 and Pd [P(C 6 H 5 ) 3 ] 4 . The metal dispersion has been determined as a function of thermal treatment. Up to 400 °C the degrees of dispersion of Pt and Pd are similar; at higher temperatures the sizes of Pt crystallites are greater than those of Pd.