Production of 5-Hydroxymethylfurfural in novel deep eutectic solvents

5-Hydroxymethylfurfural (5HMF) can be produced from lignocellulosic biomass which is a non-toxic and biodegradable source. However, 5HMF is a useful feedstock for the production of Dimethylfuran (DMF), which a biofuel with characteristics similar to gasoline. In this study, a novel self-catalysed Deep Eutectic Solvent (DES) was formulated, which are ChCl-to-p-TSA (DES1), DEAC-to-p-TSA (DES2) and ChCl-to-adipic acid (DES3). The acid components perform a dual role as a hydrogen bond donor (HBD) and as a catalyst for the dehydration of fructose to 5HMF. The study was carried in a batch system at temperature (50–110 °C), reaction time (5–180 min), fructose-to- DES mass ratio (2.5–100 g/g) and DES mixing salt-to-acid ratio 0.5:1–2:1. The reaction kinetics and the effect of the novel DES composition on the dehydration reaction were also studied. It was found that fructose was readily dehydrated to 5HMF with yield of 78.3% at a temperature of 80 °C, reaction time of 60 min, DES molar mixing ratio of 1.5:1, and a feed ratio of 5. DES2 achieved a 5HMF yield of 84.8% at the same condition as DES1 except at a different molar mixing ratio of 0.5:1 (DEAC-to-p-TSA). Conversely, DES3 accomplished 100% fructose conversion and 5HMF yield and selectivity of 90.8% at a reaction temperature of 90 °C and at a reaction time of 120 min, using a DES molar mixing ratio of 1:1 and feed ratio (initial fructose) of 2.5. The reaction kinetics studied showed that DES1 and DES2 are approximately first order while DES3 1.8