(172c) Hydrogenolysis of Biomass Derived Polyols Using Bimetallic Catalysts

Biomass derived polyols such as glycerol; sorbitol, xylitol etc have been recently identified as useful building block compounds for producing value added chemicals [1, 2]. The hydrogenolysis of the polyols to lower oxygenated compounds is an important route for a number of commodity and specialty products in the polymer and food industries. However, the complex nature of the reaction network due to several parallel and consecutive reactions leads to poor selectivity to the deoxygenated products and demands a through understanding of the reaction pathways and rational design of catalysts for improved selectivity. In this presentation, experimental results on activity, selectivity and stability of bimetallic catalysts for polyol hydrogenolysis will be addressed, following the experimental and theoretical approaches that we have recently reported for the hydrogenolysis of glycerol [3, 4]. It was observed that the bimetallic catalysts were superior to the mono-metallic catalysts and improved the desired product selectivities by suppressing some of the side reactions. As an example, a Ru-Re bimetallic catalyst decreased unwanted gaseous product formation in comparison to Ru catalyst in glycerol hydrogenolysis from 60% to 25% and improved the selectivity to deoxygenated liquid products (1,2-propanediol and propanol) from 21% to 70%. The applications of Ru, Pt, Pd based bimetallic catalysts with Re as a promoter will be presented for glycerol and other building block polyol compounds such as sorbitol, xylitol etc.

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