Synthesis of Pt-Sn nanoalloy catalysts with enhanced performance in the dehydrogenation of propane

Platinum-tin (Pt-Sn) nanoalloy catalyst supported on Al2O3 was prepared by carbonylation-impregnation method. The catalyst was characterised by means of nitrogen adsorption-desorption, X-ray diffraction and transmission electron microscope, showing the existence of Pt and Sn as Pt3Sn alloy. The analysis of particle size distribution revealed that Pt-Sn nanoparticles have high dispersion and narrow particle size distribution with an average diameter of 1.7 +/- 0.4 nm. Its catalytic performance toward propane dehydrogenation was also investigated. The propane dehydrogenation reaction showed that the as-prepared Pt-Sn/Al2O3 catalyst exhibited good dehydrogenation performance with the conversion of 27.1% and propylene selectivity of 93.3% after reacting 12 h owing to the close interaction between Pt and Sn components. Coke deposition of the used catalyst was characterised by thermogravimetric and differential thermal analysis method, revealing most of the carbon was on the surface of the support, which meant that more active sites to be accessible to maintain catalytic stability.