Patent ID: 6458997
Filing Date: 2002-10-01
Classification: A23K,B01J,C07C

Abstract:
A process for the preparation of 2-hydroxy-4-methylthiobutanoic acid comprising:introducing sulfuric acid into a first reactor comprising a continuous stirred tank reactor; introducing 2-hydroxy-4-methylthiobutanenitrile into said first reactor, the molar ratio of sulfuric acid to 2-hydroxy -4-methylthiobutanenitrile introduced into said first reactor being between about 0.6 to about 1.5; continuously hydrolyzing 2-hydroxy-4-methyl-thiobutyronitrile within said first reactor at a temperature less than about 70Â° C. to produce an intermediate aqueous hydrolysis solution containing 2-hydroxy-4-methylthiobutanamide; continuously introducing water and the intermediate aqueous hydrolysis solution into a plug flow reactor; and continuously hydrolyzing 2-hydroxy-4-methylthiobutanamide within said plug flow reactor to produce an aqueous hydrolyzate product solution containing 2-hydroxy-4-methylthiobutanoic acid.