Structure and activity of platinum–silica catalysts prepared by a combustion process

By combustion of a mixture of silicone oil and chloroplatinic acid and organic solvents, Pt–SiO₂ catalysts with Pt concentrations between 37 and 90% have been prepared and their activity in benzene hydrogenation has been tested in a static system. The special structural characteristics conferred on the catalysts by the combustion method, i.e. small Pt particles with smooth round surfaces well separated by silica, ensure good resistance to de-activation by exposure to elevated temperatures as well as to atmospheres with high humidity at low temperatures.