Chemical transformations of 5-hydroxymethylfurfural into highly added value products: present and future

Abstract

The synthesis of fuels, fuel additives, commercial and potential products from platform molecules generated by the hydrolysis of lignocellulosic biomass is a promising strategy toward the utilization of renewable feedstocks. Significant advances have been made on the various transformations (e.g., hydrogenation, oxidation, aldol condensation, rehydration, amination, polymerization, etherification and decarbonylation) of biomass-derived 5-hydroxymethylfurfural (HMF). This review firstly gives an overview of these various transformations of HMF to produce a number of fuels and chemicals, wherein the fundamental aspects of reaction mechanisms, recent progress and challenges are highlighted. Different types of catalysts are also summarized and compared in tables. One objective is to comment on the synthesis of value-added commercial and potential chemicals (e.g., furan-based polyester platform 2,5-furandicarboxylic acid (FDCA), 5-hydroxymethyl-2-furancarboxylic acid (HMFCA), 2,5-diformylfuran (DFF)). Another purpose of the review is to comment on fuels and fuel additives, including the gasoline blendstock 2,5-dimethylfuran (DMF), ethyl levulinate (EL), gamma-valerolactone (GVL), methylfuran (MF) and so on. These obtained chemicals could replace the products from petrochemical resources, reducing CO₂ emissions.