Cu-WOx-TiO2 Catalysts by Modified Evaporation-Induced Self-Assembly Method for Glycerol Hydrogenolysis to 1,3-Propanediol

A series of Cu-WOx-TiO2 catalysts for heterogeneous catalysis with different molar ratios of copper and tungsten species loadings were prepared by modified evaporation-induced self-assembly method. Their physical and chemical properties were characterized by X-ray diffraction, liquid N-2 sorption, Py-IR, Raman, inductive coupled plasma, X-ray photoelectron spectroscopy, scanning electron microscope-energy dispersive X-ray spectroscopy and transmission electron microscope techniques, and their catalytic performances were investigated in the hydrogenolysis of glycerol. The mesoporous framework for Cu-WOx-TiO2 materials can be kept well when the molar ratio of tungsten species is lower than 6%. Although the tungsten species loading is the same, the 2Cu-6WO(x)- TiO2 sample has distinctly more BrOnsted acid sites than the 2Cu-6WO(x)/TiO2-I sample prepared by impregnation method, which is owing to homogeneous tetrahedrally WOx species dispersion resulting in the formation of W5+ species. The 2Cu-6WO(x)-TiO2 sample has a higher catalytic performance than other samples, and the glycerol conversion of 12.7%, 1, 3-Propanediol selectivity of 32.3% and the ratio of 1, 3-Propanediol to 1, 2-Propanediol of 1.17 can be obtained. The 2Cu-6WO(x)-TiO2 sample shows good catalytic reusability, whose glycerol conversion 12.1% and 1, 3-PDO selectivity 30.8% can be reached even though after repeated reaction for 5 times.