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Despite 1,3-propanediol possessing high economic value, its production from glycerol hydrogenolysis is a challenging task. Herein, a series of WO x promoted Pt/Al 2 O 3 catalysts with various WO x contents were prepared and investigated for selective production 1,3-propanediol from glycerol hydrogenolysis. To explore the structure feature, these catalysts were fully characterized by BET, CO chemisorption, HRTEM, XRD ( in situ XRD), Raman, NH 3 –TPD, Py–IR, H 2 –TPR, and XPS. Among them, Pt–10WO x /Al 2 O 3 achieved the highest 1,3-propanediol yield up to 42.4%, which was ascribed to the large concentration of Brønsted acid sites, strong electronic interaction between Pt with WO x and hydrogen spillover. The strong correlation between 1,3-propanediol yield and Brønsted acid site indicated its essential role for the formation of 1,3-propanediol. Meanwhile the linear correlation between 1,2-propanediol yield and Lewis acid site gave direct evidence that Lewis acid site preferentially generated 1,2-propanediol. [ABSTRACT FROM AUTHOR]

Suppressing reverse water-gas-shift (RWGS) reaction is high desirable but challenging and underdeveloped for Cu/ZnO catalysts, particularly for commercial Cu/ZnO/Al 2 O 3 catalysts. Different from the current methodologies to reduce RWGS reaction, we report a simply surface silylation method for efficiently minimizing RWGS reaction over a commercial Cu/ZnO/Al 2 O 3 catalyst. This method suppresses STY CO (Space-time yield) from 97.4 to 0.7 g CO ·kg cat −1·h−1, improving STY MeOH from 20.2 to 39.9 g MeOH ·kg cat −1·h−1 and methanol selectivity from 15.1 to 92.9 mol%. The combination of characterization methods and density functional theory calculations provide insight into the suppressing mechanism of surface silylation on catalyst. A hydroxyl (on ZnO)-promoted RWGS reaction cycle is discovered, which can be efficiently inhibited by the consuming of hydroxyls via surface silyation. Our results provide a way to regulate RWGS reaction on Cu/ZnO-based catalysts and are expected to the further use of silylation strategy to tune the interconversion of CO and CO 2 via RWGS/WGS reaction on hydrogenation catalysts. [Display omitted] • Surface silylation suppresses RWGS reaction on Cu/ZnO/Al 2 O 3 for CO 2 hydrogenation, promoting S CH3OH from 15.3 to 92.9 mol%. • A Zn-OH promoted RWGS mechanism is found, i.e., H spillover from Cu to the reactants via the Zn-OHs boosts RWGS reaction. • Consuming hydroxyls via the surface silylation inhibits the H spillover and further RWGS reaction. [ABSTRACT FROM AUTHOR]