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The selective hydrogenolysis of glycerol to 1,3propanediol (1,3-PDO) is an important yet challenging reaction because it requires the selective cleavage of the sterically hindered secondary C−O bond of glycerol. In this work, we have developed a new catalyst, 0.1Au-2Pt/7.5W/Al, which affords both high glycerol conversion (77.5%) and 1,3-PDO selectivity (54.8%), which are significantly higher than the Au-free counterpart. HAADF-STEM reveals that the structure of 0.1Au-2Pt/7.5W/Al is characterized with ∼2 nm Pt NPs decorated with Au-WO x at the periphery, where the Au additive exists most likely as single atoms. Chemisorption and XPS show that the electron transfer from W to Au can help to weaken the strong metal support interaction (SMSI) between Pt and WO x , and thus greatly enlarges the exposed Pt surface and increases the H-spillover capacity. The 2-butanol dehydration in H 2 reveals that the H-spillover capacity is proportional to the number of Bronsted acid sites, which, in conjunction with the only water desorption in H 2 -TPD results, strongly suggests that the active sites for breaking the secondary C−O bond of glycerol should be Bronsted acid sites generated by the H-spillover at the interface between Pt and WO x , and the modification by the Au additive increases the number of interfacial sites, and thus enhances the 1,3-PDO yield.

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Various TiO2, SiO2, Al2O3, and Nb2O5–Al2O3 supported Pt catalysts have been prepared by urea precipitation method for catalytic hydrodeoxygenation (HDO) of diphenyl ether (DPE) as a 4-O-5 aryl-ether lignin model compound. The selectivity toward deoxygenated product cyclohexane increased obviously with Nb2O5·nH2O decorated, owing to the significant promotion effect of NbO x species and acid sites on C–O bond cleavage. At higher pressure (3.0 MPa H2), DPE underwent a HYD route, while direct hydrogenolysis route occurred at low pressure (0.1 MPa H2). In addition, the reaction rate constants and activation energies were obtained in the temperature range from 160 to 220 °C. Based on the Arrhenius law, the activation energy for the cleavage of the C–O bond in DPE was calculated to be 91.22 kJ/mol. It was noteworthy that the Pt/20Nb–Al2O3 showed higher stability than Pt/Al2O3 for hydrodeoxygenation of diphenyl ether, which can be attributed to its water-tolerant Lewis acid sites.

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