Manufacture of furfural in biphasic media made up of an ionic liquid and a co-solvent

Abstract Xylose was converted into furfural operating in a medium containing the acidic ionic liquid (AIL) 1-butyl-3-methylimidazolium hydrogen sulfate, in the presence of toluene as a co-solvent. No catalytic species different from the AIL were needed for furfural production from xylose. Operating at 100–140 °C for 15–480 min in media containing 10 g xylose/100 g AIL and 2–4 g toluene/g (AIL + xylose), most furfural generated in the AIL phase was transferred to the co-solvent, limiting the losses caused by undesired side reactions. Operating under optimal conditions (140 °C for 240 min using 4.4 g toluene/g initial AIL phase), xylose was almost completely consumed, and furfural was obtained at 73.8% of the stoichiometric yield.