Performance and S resistance of novel supported PdPt catalysts on Al2O3-TiO2 material in hydrogenation of biphenyl

摘要

The Al2O3-TiO2 materials were synthesised by sol-gel technique with low and high Ti content (molar ratios of Al/Ti=25 and 2). The samples were used as supports of PdPt catalysts with total loading metals of 1 wt-% (molar ratio of Pd/Pt=4) by incipient wetness impregnation using H2PtCl6 and Pd(NO3)x H2O. The samples were characterised by absorption-desorption of N2, X-ray diffraction, transmission electron microscopy and were tested in the hydrogenation (HYD) of biphenyl model reaction. The PdPt catalysts supported on the mixed Al2O3-TiO2 material with low Ti content exhibited a high HYD activity in comparison with the high content Ti sample. It is proposed that the presence of Ti could modify the catalytic behaviour as a result of changes in the electronic properties of the active phase, interacting with such species. Moreover, Ti increased the sulphur resistance of the metallic particles under HYD conditions.