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Graphene oxide (GO) has proved to be a highly active and reusable solid acid catalyst for glycerol esterification with acetic acid in the synthesis of bioadditives diacylglycerol (DAG) and triacylglycerol (TAG). The effects of reaction temperature, molar ratio of acetic acid to glycerol, catalyst amount and reaction time were investigated. A 90.2% combined selectivity of DAG and TAG with complete glycerol conversion was achieved at 120 °C for 6 h over GO. Final characterization shows that the active site of GO is the remaining SO 3 H group. [ABSTRACT FROM AUTHOR]

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]

Highlights: [•] Addition of SiO2 to PtW/Zr greatly enhanced activity and 1,3-propanediol selectivity. [•] 54.3% conversion and 52.0% 1,3-propanediol selectivity were achieved over 5PtW/ZrSi. [•] A model scheme of WO x transformation due to SiO2 doping has been built. [•] Pt and polytungstate have been identified as the dominant active phases. [•] Glycerol hydrogenolysis conforms to the dehydration–hydrogenation mechanism. [Copyright &y& Elsevier]