Catalyst design strategy toward the efficient heterogeneously-catalyzed selective oxidation of 5-hydroxymethylfurfural

The selective oxidation of 5-hydroxymethylfurfural (HMF), a versatile bio-based platform molecule, leads to the formation of several intriguing and useful downstream chemicals, such as 2,5-diformylfuran (DFF), 5-hydroxymethyl-2-furancarboxylic acid (HMFCA), formyl 2-furancarboxylic acid (FFCA), 2,5-furandicarboxylic acid (FDCA) and furan-2,5-dimethylcarboxylate (FDMC). These products have been extensively employed to fabricate novel polymers, pharmaceuticals, sustainable dyes and many other value-added fine chemicals. The heart of the developed HMF oxidation processes is always the catalyst. In this regard, this review comprehensively summarized the established heterogeneous catalyst design strategy for the selective oxidation of HMF via thermo-catalysis. Particular attention has been focused on the reaction mechanism of HMF oxidation over different catalysts as well as enhancing the catalytic performance of the catalyst through manipulating the properties of the support and fabricating of multi-component metal nano-particles and oxides. The current challenges and possible research directions for the catalytic oxidation of HMF in the future are also discussed.