STUDIES ON PTXSNY BIMETALLICS IN NAY .2. FURTHER CHARACTERIZATION ANDCATALYTIC PROPERTIES IN THE DEHYDROGENATION AND HYDROGENOLYSIS OF PROPANE

CO adsorption and desorption, as studied by IR spectroscopy and mass s pectrometry has been used to characterize PtNaY and PtxSnyNaY samples. The change observed between adsorbed CO spectra and CO TPD has been a ttributed to an increase of the particle sizes due to the addition of Sn to Pt. The catalytic properties of these materials were studied by using propane dehydrogenation and propane hydrogenolysis. The TOF of p ropene formation is nearly the same for all samples and the apparent a ctivation energy remains unchanged, indicating that no change in the P t dehydrogenation properties is induced by adding Sn. In contrast the hydrogenolysis properties are deeply depressed by alloying Pt to Sn, t hese changes being attributed to a dilution effect rather than to an e lectronic effect. (C) 1997 Academic Press.