Activity and Selectivity of Base Promoted Mono and Bimetallic Catalysts for Hydrogenolysis of Xylitol and Sorbitol

摘要

Hydrogenolysis of polyols (sorbitol and xylitol) was investigated using supported mono and bimetallic catalysts in aqueous medium. The role of different bimetallic formulations, supports, and solid acid and base promoters on catalytic activity and selectivity was studied in a batch slurry reactor. It was observed that the major products formed with Ru catalysts were C_2 and C_3 glycols and alcohols. The addition of a second metal such as Re promotes catalytic activity, whereas addition of solid base promoters enhance both activity and selectivity of liquid phase products. Based on the evaluation of different catalysts and studies with intermediate products as substrates, a reaction pathway and possible mechanism of hydrogenolysis are discussed.