The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 26, 1992
Filed:
Oct. 23, 1990
Applicant:
Inventors:
Kamlesh K Bhatia, Newark, DE (US);
Neville E Drysdale, Newark, DE (US);
John R Kosak, Greenville, DE (US);
Assignee:
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
549274 ;
Abstract
An improved process for the recovery of lactide or other dimeric cyclic ester from a gas stream containing the cyclic ester and such hydroxylic impurities as water and open-chain hydroxycarboxylic acids by scrubbing the gas stream with a nonpolar water-immiscible solvent at a temperature at which the cyclic ester is removed from the solvent and any water present in the gas stream is vaporized from the solvent. The cyclic ester is recovered from the solvent in a high state of optical purity.