AZEOTROPIC DISTILLATION OF CYCLIC ESTERS OF HYDROXY ORGANIC ACIDS

摘要

Cyclic esters of hydroxy organic acids can be produced and recovered via azeotropic distillation. In certain embodiments, cyclic esters such as glycolide and lactide can be produced from a fermentation broth or other feedstream that comprises a hydroxy organic acid, an ammonium salt of a hydroxy organic acid, or an ester of a hydroxy organic acid using azeotropic distillation. The hydroxy organic acid for the feedstream or the organic acid derived from the feedstream by decomposition is related to produce the cyclic ester. In other embodiments a crude composition of a cyclic ester of an organic ester can be purified using azeotropic distillation. The feedstream (10) and an azeotroping agent (12) are mixed in a reactor (14). A first vapor stream (20) can be purified using a first column (22), a second column (27) and a separator (38). A first column bottoms stream (24) from the first column (22) can be recycled back to reactor (14).