Effective Hydrogenolysis of Glycerol to 1,3-Propanediol over Metal-Acid Concerted Pt/WOx/Al2O3 Catalysts

Graphical Pt at it, again ! The highest 1,3-PDO yield was obtained over the Pt/WO x /Al 2 O 3 catalyst with a medium domain size of WO x and a Pt/W atomic ratio of 1/4∼1/2, which favored the dispersion of Pt and maximized the number of Pt−WO x interface sites, and consequently promoted the in-situ production of strong Brønsted acid sites. Selective cleavage of secondary C−O bond is an important yet challenging strategy in glycerol valorization, and the product 1,3-propanediol (1,3-PDO) is of great value in polyester industry. Herein, we report a series of Pt/WO x /Al 2 O 3 catalysts for selective hydrogenolysis of glycerol in a fixed-bed reactor and obtain the highest space-time yield of 1,3-PDO (191.7*10 −3 g 1,3-PDO h −1 g −1 cat. ) to date. Both Pt and W have substantial effects on the 1,3-PDO yield with the optimum Pt/W atomic ratio of 1/2∼1/4. Spectroscopy characterizations as well as chemisorption experiments reveal that at the medium domain size of WO x , hydrogen spillover can take place to the greatest extent due to the improved dispersion of Pt and the suitable reducibility of WO x . Dehydration/dehydrogenation tests of 2-butanol suggest that strong Brønsted acid sites are created via hydrogen dissociation at the Pt−WO x interface and spillover to the neighboring oxygen atom. Such in situ formed protons are critical to the selective cleavage of secondary C−O bonds of polyols.