PT-SN AL2O3 SOL-GEL CATALYSTS - METALLIC PHASE CHARACTERIZATION/

Highly dispersed platinum was found in Pt-Sn/Al2O3 catalysts prepared by the sol-gel method, i.e., cogelation of aluminum tri-sec-butoxide a nd tetrabutyltin and subsequent impregnation with hexachloroplatinic a cid. X-ray diffraction studies showed that the cell parameter of pure platinum is not modified in bimetallic Pt-Sn samples. Moreover, energy dispersive X-ray analysis studies (EDX) showed that platinum, but not tin, was detected in the catalysts where tin was incorporated by the sol-gel coprecipitation of tin and aluminum. Incorporation of tin into the alumina network is suggested.