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:
Sep. 18, 2007
Filed:
Dec. 27, 2000
Applicants:
Philippe Carvin, Lyons, FR;
Jean-claude Masson, Lyons, FR;
Inventors:
Philippe Carvin, Lyons, FR;
Jean-Claude Masson, Lyons, FR;
Assignee:
Rhodia Polyamide Intermediates, Saint Fons, FR;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D 9/02 (2006.01); B01D 9/00 (2006.01); C07D 223/10 (2006.01);
U.S. Cl.
CPC ...
Abstract
A process is described for purifying lactams, in particular the lactams obtained by cyclizing hydrolysis of an aminoalkylnitrile, and more particularly to the purification by crystallization of ε-caprolactam obtained by cyclizing hydrolysis of aminocapronitrile. This crystallization is carried out on the cyclization reaction medium after hydrogenation, removal of volatile compounds, and treatment with an ion-exchange resin.