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:
Feb. 28, 1995
Filed:
Apr. 15, 1994
George C Zima, Kingsport, TN (US);
T Hugh Williams, Fall Branch, TN (US);
Mark R Shelton, Kingsport, TN (US);
Eastman Chemical Company, Kingsport, TN (US);
Abstract
This invention relates to a four step process for purifying amido-carboxylic acids by liquid/liquid extraction from a reaction mixture containing an amido-carboxylic acid. The first step involves distilling impurities from a reaction mixture containing an amido-carboxylic acid to form a distillate residue. The second step involves mixing the distillate residue with a nonpolar hydrocarbon solvent wherein the mixture is maintained above the freezing point of the distillate residue. The third step involves allowing the hydrocarbon solvent and distillate residue to achieve phase separation of an organic phase containing the amido-carboxylic acid and an organic phase containing the nonpolar hydrocarbon solvent. The fourth step involves separating the organic phase containing the nonpolar hydrocarbon solvent from the organic phase containing the amido-carboxylic acid.