From the dissolution to the extraction of carbohydrates using ionic liquids

Lignocellulosic biomass is an alternative raw material for the production of biofuels. The conversion of biomass to biofuels begins with pretreatment to produce amorphous cellulose which can be hydrolysed to sugars. The use of ionic liquids has been described as a new potentially viable development in this area. Nevertheless, phase equilibria with biomass-derived compounds and also sugars, is still lacking in the literature. To overcome the lack of experimental data on phase equilibria of biomass carbohydrates in ionic liquids, the solubility of fructose, sucrose and lactose in ionic liquids was measured within a temperature range from 280 K to 390 K. Solubility data were successfully correlated using NRTL and UNIQUAC thermodynamic models. In this work, the possibility of extracting carbohydrates from ionic liquids using ethanol has also been evaluated. Results indicate that ethanol could be used as an antisolvent to separate sugars from ionic liquids.