Mechanistic insights into the conversion of glucose to formic acid over vanadium-based catalyst

Abstract

The catalytic oxidation of biomass-derived compounds represents a promising and sustainable pathway for the production of valuable chemicals, such as formic acid, which is a key candidate for hydrogen storage and CO₂-neutral energy applications. This study investigates the selective oxidation of glucose to formic acid using vanadium oxide supported on titania (VOx/TiO₂) as the catalytic system. This paper elucidates the reaction mechanism and analyzes the product distribution over time under controlled experimental conditions. The system exhibited selective glucose conversion, with formic acid emerging as the primary product, followed by intermediates such as arabinose, glyceraldehyde, acetic acid, and formaldehyde. Mechanistic studies suggested that the selective formation of formic acid proceeds via successive C1–C2 bond cleavage assisted by the peroxo species of vanadium. These findings highlight the key role of molecular and activated oxygen in the reaction pathway, while excluding the direct decomposition pathways for formic acid. This mechanistic insight and the role of vanadium-based peroxo species formed on the catalyst surface provide a critical foundation for optimizing catalyst design for biomass conversion processes.