Patent ID: 6444842
Filing Date: 2002-09-03
Classification: C07C

Abstract:
A method for the preparation of a carboxylic acid ester of an alkylene glycol monoalkyl ether comprisinga) reacting in a reaction column a monocarboxylic or halogenated monocarboxylic acid having from 1 to 10 carbon atoms with an alkylene glycol monoalkyl ether having the formula â€ƒwherein n=0-6; R1, R2=H, CH3â€”(CH2)nâ€”; provided when n=6, R1 or R2=H, and X=Cl, Br, F in the presence of an acid catalyst;b) distilling the mixture in a distillation column, while using the water of reaction to azeotrope the carboxylic acid ester and unreacted alkylene glycol monoalkyl ether; c) transferring the distillate of (b) to an overhead phase extractor/separator and contacting with an effective amount of inert solvent to enable formation of at least two phases; d) separating out the resulting phases of the mixture so as to form a water phase and an oil (product) phase; and, e) distilling the oil phase to recover monocarboxylic acid ester product and inert solvent.