Separation of carbohydrates and sugar alcohols from ionic liquids using antisolvents

• Separation between carbohydrates and ILs through precipitation with antisolvents.
• The effect of operatory conditions in separation performance was studied.
• Carbohydrate extraction and IL-recovery higher than 83% in most cases.

Interest in the application of ionic liquids (ILs) for biorefining purposes has been growing in the last decade. In such biorefineries separation processes involving carbohydrates and ILs are required for process design. In this work, separation between carbohydrates or sugar alcohols and ILs by means of precipitation was studied extensively for 16 different mixtures. Process variables such as temperature, antisolvent/IL ratio, and different antisolvents, ILs and solutes were studied. Carbohydrate extraction and IL recovery in the process were evaluated. For more than 80% of the studied mixtures, ionic liquid recovery and carbohydrate extraction were higher than 83%, using the optimised conditions. These results show the suitability of antisolvents for separation technologies in biorefining processes using ILs.