Aqueous two‐phase/reverse micelle continuous process for recycling and simultaneous purification of polar ionic liquid from enzymatic hydrolysate

Abstract

AbstractBACKGROUNDRecently, ionic liquid (IL) involved pretreatment and enzymatic saccharification of cellulose toward biofuel have attracted extensive attention. However, separation and recycling of ionic liquid from enzymatic hydrolysate pose challenges to their large‐scale application. Almost all present work has focused on the recovery rate of IL, but little work has been done to analyze the purity and functioning of recovered IL. In this work, IL was recycled and purified from hydrolysis mixtures using an aqueous two‐phase/reverse micelle process (APTs/RM).RESULTSAn ionic liquid recovery yield of 92.3% and purity of 99.1% was obtained from the aqueous two‐phase and reverse micelles extraction process with optimized parameters. Impurities (e.g. lignin, HCO3−, (NH4)2SO4 and enzyme protein) were removed from the ionic liquid. When recycling over 10 runs, the APTs/RM process has distinct advantage over other reported recovery methods.CONCLUSIONIt is demonstrated that the APTs/RM process is efficient for recycling and simultaneous purification of polar ionic liquid from an enzymatic hydrolysate mxiture. This method is potentially sustainable, efficient, and attractive for large‐scale application. © 2014 Society of Chemical Industry