Patent ID: 8148518
Filing Date: 2012-04-03
Classification: C07D,C08B,Y02P

Abstract:
1. A process for making cellulose esters, said process comprising: (a) dissolving cellulose in a carboxylated ionic liquid to thereby form a cellulose solution; (b) contacting said cellulose solution with an acylating reagent optionally in the presence of a catalyst to thereby provide an acylated cellulose solution comprising a cellulose ester, wherein said cellulose ester comprises at least one acyl group originating from said carboxylated ionic liquid; (c) contacting said acylated cellulose solution with a non-solvent to cause at least a portion of said cellulose ester to precipitate and thereby provide a slurry comprising precipitated cellulose ester and said carboxylated ionic liquid; (d) separating at least a portion of said precipitated cellulose ester from said carboxylated ionic liquid to thereby provide a recovered cellulose ester and a separated carboxylated ionic liquid; and (e) optionally recycling at least a portion of said separated carboxylated ionic liquid for use in dissolving additional cellulose.