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. 21, 2012
Filed:
Nov. 06, 2009
Takushi Azemi, Ehime, JP;
Yoshiyuki Koizumi, Ehime, JP;
Takushi Azemi, Ehime, JP;
Yoshiyuki Koizumi, Ehime, JP;
Sumitomo Chemical Company, Limited, Tokyo, JP;
Abstract
A process for producing methionine, while corrosion of a pipe and a reaction vessel is well inhibited, is provided including the following steps () to (), wherein a content of thiols in 3 -methylthiopropanal is 500 ppm or less, based on the propanal, and a content of hydrogen sulfide in 3-methylthiopropanal is 60 ppm or less, based on the propanal; step () in which 3 -methylthiopropanal is reacted with hydrogen cyanide in the presence of a base to give 2 -hydroxy -4-methylthiobutanenitrile; step () in which the 2-hydroxy-4-methylthiobutanenitrile obtained in step () is reacted with ammonium carbonate to give 5-(β-methylmercaptoethyl) hydantoin; and step () in which the 5-(β-methylmercaptoethyl)hydantoin obtained in step () is hydrolyzed in the presence of a basic potassium compound to give methionine.