Combined treatments for producing 5-hydroxymethylfurfural (HMF) from lignocellulosic biomass

An efficient production of 5-hydroxymethylfurfural (HMF) from raw lignocellulosic biomass is achieved through combinational treatments of diluted acid/base-assisted pretreatment and catalytic conversion. Remarkably, an HMF yield of around 79 mol% could be achieved when the raw lignocellulosic biomass (wood chips) was pre-treated in diluted NaOH solution (3 wt%) and then catalyzed in the system using CrCl₃·6H₂O as the catalyst and 1-butyl-3-methyl imidazolium chloride ([BMIM]Cl) as the solvent at 120 °C for 2 h. In addition, the activation energy for producing HMF was calcuted to be around 74 kJ/mol in our system. The combinational treatments proposed in this study demonstrate an effective transformation of raw lignocellulosic biomass into HMF with a high yield.