Process for preparing colorless methionine
AssigneeSumitomo Chemical Company, Limited
InventorsToshio Kawabata, Toshio Ishiyama
Life of this patent
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Abstract
Methionine devoid of a coloring matter can be obtained from the aqueous solution of alkali salts of methionine prepared by hydrolysis of 5-(.beta.-methylmercaptoethyl)-hydantoin with an alkali by decolorizing the said solution with reducing sulfur compound and thereafter collecting methionine as colorless crystals.
Claims10
A process for preparing colorless methionine from the aqueous solution of alkali salts of methionine prepared by hydrolysis of 5-(.beta.-methylmercaptoethyl)-hydantoin with an alkali, which comprises treating the said solution with a reducing sulfur compound before or during neutralizing the said solution with an acid ,and thereafter collecting colorless methionine from the resulting decolorized solution of methionine, the reducing sulfur compound being sulfur dioxide, monosulfites, disulfites, bisulfites, thiosulfates, dithionites or a mixture thereof.
A process for preparing colorless methionine from the aqueous solution of alkali salts of methionine prepared by hydrolysis of 5-(.beta.-methylmercaptoethyl)hydantoin with an alkali, which comprises treating an aqueous solution of methionine, which is obtained by neutralizing said solution with an acid, with a reducing sulfur compound, and thereafter collecting colorless methionine from the resulting decolorized solution of methionine, the reducing sulfur compound being sulfur dioxide, monosulfites, disulfites, bisulfites, thiosulfates, dithionites or a mixture thereof.
Dependencies are inferred from the claim text.