Exploring catalytic oxidation pathways of furfural and 5-hydroxymethyl furfural into carboxylic acids using Au, Pt, and Pd catalysts: a comprehensive review

The oxidation of 5-hydroxymethylfurfural (HMF) and furfural into valuable products such as carboxylic (furanic) acids has garnered significant attention in catalysis. This review presents the current state of research in the catalytic oxidation of HMF and furfural, aiming to elucidate the intricate mechanisms involved in these transformations. The review highlights how the choice of catalyst support plays a crucial role in influencing the catalytic performance of gold (Au), platinum (Pt), and palladium (Pd) but also the corresponding bimetallic catalysts on catalytic activities and selectivities to various products. It also provides a deeper rationale thanks to a detailed review of the theoretical approaches related to the catalytic oxidation of HMF and furfural. Additionally, it highlights the need to give further insights into the factors and pathways promoting the degradation of intermediates during the oxidation of furfural and HMF to achieve superior catalytic performance.