Patent ID: 6545179
Filing Date: 2003-04-08
Classification: C07C

Abstract:
A process for the production of methionine, said process capable of industrial application, which comprises:(a) contacting 2-hydroxy-4-methylthio butanenitrile with ammonia or a solution containing ammonia to produce a first product comprising 2-amino-4-methylthio butanenitrile, (b) reacting the 2-amino-4-methylthio butanenitrile with a ketone and an alkali metal hydroxide in a reactor to produce a second product comprising methionine amide, (c) removing any unreacted ketone and ammonia from the second product stream, (d) hydrolysing the methionine amide in the presence of a catalyst comprising titanium to produce a third product stream comprising ammonium methioninate, said catalyst having a porosity of from 5 to 1000 nm, a total pore volume of from 0.2 to 0.55 cm3/g and a surface area of from 30 to 150 m2/g, and (e) liberating methionine from the ammonium methioninate, wherein the methionine amide is contacted with an acidic resin prior to the hydrolysis.