Advances in biomass transformation to 5-hydroxymethylfurfural and mechanistic aspects

Biomass-derived 5-hydroxymethylfurfural (HMF) has been emerged as a key platform chemical for the production of fine chemicals and liquid fuels. The direct transformation of cellulose and lignocellulosic biomass into HMF in ionic liquids and organic solvents is most desired in terms of process economics and sustainability. The focus of this review is purely on the HMF production from cellulose and lignocelluloses and mechanistic aspects of HMF formation in order to bridge the gap in understanding the factors responsible for selective conversion and selection of catalyst. Additionally, present review is devoted exclusively to the latest developments, namely microwave-assisted degradation of cellulose to HMF, application of solid acid and ionic-liquid catalysis to address their effectiveness for HMF production. Approaches for the cellulose transformation into HMF are especially emphasized in order to explore newer avenues of biomass as renewable feedstock for energy and chemicals.