Recovery of ionic liquid via a hybrid methodology of electrodialysis with ultrafiltration after biomass pretreatment

Hybrid membrane-based methodology of electrodialysis (ED) with ultrafiltration (UF) was employed to recover the IL BmimBr (1-Butyl-3-methylimidazolium bromide) after biomass fractionation. Ultrafiltration was used to remove the residual lignin in IL solutions. Influence of molecular weight interception of UF treatment, initial IL concentration in dilute section, applied voltage and flow rate in each section of ED module were studied in detail. In this study, the highest overall IL recovery ratio reached 75.2% and the current efficiency of ED process approached 79.1%. Besides, the highest IL recovery performance of specific energy consumption was about 514.1 g/kw.h. Insight gained from this study suggests a potential methodology for IL recovery after the pretreatment process for biomass. (C) 2016 Elsevier Ltd. All rights reserved.