A study of cellulose dissolution in ionic liquid- water brines

A series of morpholinium salts were prepared in order to investigate their efficacy in dissolution of cellulose. These ionic liquids were prepared under normal bench‐top experimental BLOCKINconditions BLOCKINrendering BLOCKINthese BLOCKINionic BLOCKINliquids BLOCKINwell BLOCKINsuited BLOCKINfor BLOCKINapplied BLOCKINresearch BLOCKINin industrial scale. Most of the ionic liquids prepared were halide free, but contained approximately 60000 ppm water due to their hygroscopicity. It was found that [AMMorp][OAc]‐brine BLOCKINand BLOCKIN[AMMorp][HSO 4 ]‐brine, BLOCKINat BLOCKIN120 0 C BLOCKINin BLOCKIN20 BLOCKINmin, BLOCKIN BLOCKINcan BLOCKINdissolve BLOCKIN26 wt% and 8 wt% cellulose, respectively. In case of [BMMorp][OAc], [BMMorp][OAc]‐ brine was not able to dissolve cellulose and addition of some amount of halogen‐ containing ionic liquid was required to dissolve cellulose. The combination of 70% [BMMorp][OAc] BLOCKINwith BLOCKIN23.3% BLOCKIN[BMMorp][Br] BLOCKINand BLOCKIN6.7 BLOCKINwt% BLOCKINwater BLOCKINenabled BLOCKINthe BLOCKINdissolution of 6 wt% cellulose without any pretreatment, at 80 0 C for 24 h. Similarly, 86.7 % [BnMMorp][OAc] with 7% [BnMMorp][Cl] and 6.3 wt% water could dissolve 22 wt% cellulose at 120 0 C in 20 min. The organic electrolytic solutions of ionic liquids with various BLOCKINinvestigated BLOCKINamines BLOCKINcould BLOCKINnot BLOCKINdissolve BLOCKINcellulose BLOCKINat BLOCKINhigh BLOCKINtemperature, BLOCKINwhile BLOCKINthe solutions containing ethanol and 2‐butanol could dissolve 2 wt% and 4 wt% cellulose respectively BLOCKINat BLOCKIN70 0 C BLOCKINin BLOCKIN24 BLOCKINh. BLOCKINThe BLOCKINoptical BLOCKINmicroscopy BLOCKINimages BLOCKINunraveled BLOCKINthe BLOCKINbehavior BLOCKINof cellulosic fibers in different solvent systems. Importantly, recovered ionic liquid still showed BLOCKINa BLOCKINstrong BLOCKINability BLOCKINfor BLOCKINdissolution BLOCKINof BLOCKINcellulose.