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:
Oct. 26, 1976
Filed:
Sep. 08, 1975
Roger Robert Gaudette, Nashua, NH (US);
James Edward Philbrook, Nashua, NH (US);
Jon Carl Thunberg, Amherst, NH (US);
W. R. Grace & Co., Columbia, MD (US);
Abstract
Iminodiacetonitrile is prepared by a process comprising: (a) forming an aqueous reaction mixture by admixing water, hexamethylenetetramine, formaldehyde, and HCN; and (b) forming iminodiacetonitrile by passing the aqueous reaction mixture through a continuous reaction zone while maintaining the temperature within the continuous reaction zone at 50.degree.-250.degree. C. The resulting iminodiacetonitrile can be recovered or it can be hydrolyzed to form an alkali metal salt of iminodiacetic acid which can be recovered or converted to iminodiacetic acid which can be recovered. In other embodiments: (a) the hexamethylenetetramine solution and the formaldehyde solution can be combined before being admixed with the HCN; or (b) the formaldehyde solution and the HCN can be admixed with a stabilizing acid to form an acid stabilized aqueous solution of formaldehyde and HCN before being admixed with the hexamethylenetetramine solution in the reaction zone in which iminodiacetonitrile is formed.