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:
Apr. 30, 1991
Filed:
Oct. 11, 1989
Applicant:
Inventor:
Jon C Thunberg, Milford, NH (US);
Assignee:
W. R. Grace & Co.-Conn., , CT (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
562554 ;
Abstract
The separation and recovery of iminodiacetic acid and sodium sulfate decahydrate from sodium sulfate solutions such as the liquor generated in the production of iminodiacetic acids are disclosed. The separation is accomplished by adjusting the temperature of the sodium sulfate solutions to crystallize the iminodiacetic acid and sodium sulfate decahydrate. Nitrilotriacetic acid optionally can be isolated prior to the crystallization of the IDA and sodium sulfate decahydrate.