Recent advances in catalytic conversion of biomass derived 5-hydroxyme-thylfurfural into 2,5-furandicarboxylic acid

With the aggravation of global environmental problems and the shortage of fossil resources, it is particularly important to seek environmentally friendly renewable chemicals and fuels that can replace fossil resources. As a typical biomass-derived product, 5-hydroxymethylfurfural (HMF) is one of the most important platform molecules, as its chemical structure allows the preparation of various high value-added products via catalytic routes. 2,5-Furandicarboxylic acid (FDCA) produced after oxidation of HMF, is a promising bio-derived building block and valuable monomer of polyethylene furandicarboxylate (PEF) being considered as a future alternative to polyethylene terephthalate (PET). Thermocatalytic transformation of HMF into FDCA in recent years has obvious advantages in terms of product yield and purity but suffers from the high energy consumption and high oxygen pressure, limiting its application in industry. Catalytic routes based on electrocatalysis and biocatalysis are developing technology for the production of these kind of high value-added chemicals due to green chemistry approaches, energy efficiency, mild reaction conditions and high selectivity, which is an important development direction for the effective utilization of biomass resource in the future. In this review, the catalytic routes for the preparation of HMF from hexose and the production of FDCA from HMF are systematically summarized. The effects of different catalytic systems on the yield of target products were analyzed, and the limitations of current catalytic systems were expounded. Moreover, the current research trends and future research directions are also overviewed in the hope of provide some feasible and valuable ideas for the development of efficient catalytic systems for the conversion of biomass into high value-added platform chemicals.