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:
Nov. 26, 1991
Filed:
Oct. 24, 1989
Applicant:
Inventors:
Assignee:
Enichem Anic S.p.A., Palermo, IT;
Primary Examiner:
Int. Cl.
CPC ...
C07B / ; C07C / ;
U.S. Cl.
CPC ...
564160 ; 564125 ;
Abstract
A method of removing copper from oxamide obtained through a process which involves the use of copper catalysts, by contacting it with an aqueous solution of a suitable complexing agent, which is capable of forming copper-containing water-soluble complexes and imparts to the aqueous solution a pH comprised between 2 and 8, optionally repeating the contacting step and, finally, recovering the purified oxamide by solid-liquid separation techniques. The claimed process affords oxamide containing less than 25 ppm of copper.