Kinetic Modeling of Glucose Oxidation to Tartaric Acid over Monometallic Pt/TiO₂ and Bimetallic AuPt/TiO₂ Catalysts: Role of Bimetals on C–H and C–C Cleavages

Abstract

Oxidation of glucose to tartaric acid is important in the context of biomass conversion. Aqueous conversion of glucose in a base-free medium provides an atomic and energy efficient way for synthesizing tartaric acid and derivatives for pharmaceutical, cosmetic, and polymer industries. However, to date, there has been no systematic study on kinetic modeling on aqueous glucose oxidation to tartaric acid. Therefore, in this work, we have conducted detailed kinetic modeling on aerobic oxidation of glucose over synergistic bimetallic AuPt/TiO 2 catalysts at 80−110 °C in a base-free medium. In particular, the reaction network for the oxidation of glucose involving C−H and C−C cleavage reactions has been quantitatively assessed. The catalytic performances for both monometallic Pt/TiO 2 and bimetallic AuPt/TiO 2 catalysts has been compared and discussed in detail. The role of Au addition to Pt catalysts on activity and selectivity, as well as product distribution, has also been discussed along with reaction pathways. The kinetic analysis for conversion of glucose to tartaric acid and derivatives provides important data for process development of synthesizing useful carboxylates in the future.