Aerobic Oxidation of Xylose to Xylaric Acid in Water over Pt Catalysts

Abstract Energy‐efficient catalytic conversion of biomass intermediates to functional chemicals can make bio‐products viable. Herein, we report an efficient and low temperature aerobic oxidation of xylose to xylaric acid, a promising bio‐based chemical for the production of glutaric acid, over commercial catalysts in water. Among several heterogeneous catalysts investigated, Pt/C exhibits the best activity. Systematic variation of reaction parameters in the pH range of 2.5 to 10 suggests that the reaction is fast at higher temperatures but high C−C scission of intermediate C 5 ‐oxidized products to low carbon carboxylic acids undermines xylaric acid selectivity. The C−C cleavage is also high in basic solution. The oxidation at neutral pH and 60 °C achieves the highest xylaric acid yield (64 %). O 2 pressure and Pt amount have significant influence on the reactivity. Decarboxylation of short chain carboxylic acids results in formation of CO 2 , causing some carbon loss; however, such decarboxylation is slow in the presence of xylose. The catalyst retained comparable activity, in terms of product selectivity, after five cycles with no sign of Pt leaching.