초록
<P>A sustainable cyclic process for the enzymatic saccharification of ionic liquid (IL)-pretreated cellulose, in which the IL is recovered and recycled, has been developed. Homogeneous cellulose solutions in the IL 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]) were used to prepare amorphous cellulose by antisolvent precipitation with water, ethanol or equimolar water–ethanol mixtures as green molecular solvents. Several operation parameters (<I>e.g.</I>, solvent, temperature, ultrasounds, <I>etc.</I>) for both cellulose precipitation and the washing steps were tested to achieve full desorption of the IL from the cellulose backbone. In the best conditions, up to 99.7% IL was recovered, which was then successfully reused in further cellulose dissolution/precipitation cyclic processes. Furthermore, the cellulose regenerated in each cycle was an excellent substrate for enzymatic hydrolysis, permitting full hydrolysis (<I>i.e.</I>, up to 97.7% hydrolysis after 4 h at 50 °C) by the combined action of both cellulase and cellobiase enzymes, that provides a clear glucose solution. The excellent suitability of this glucose solution for growing aerobic <I>Saccharomyces cerevisiae</I> was demonstrated.</P><BR><BR><P>Graphic Abstract</P><P>A sustainable cyclic process for the enzymatic saccharification of ionic liquid (IL)-pretreated cellulose, in which the IL is recovered and recycled, has been developed.<BR><IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2gc35905g'><BR></P>