| 摘要 |
1,128,860. Potassium methionate. FARBWERKE HOECHST A.G. 2 Dec., 1966 [16 Dec., 1965], No. 54006/66. Heading C2C. Potassium methionate is prepared by reacting potassium sulphite with methylene chloride at a pressure below 20 atmospheres gauge and adding to the reaction mixture water in such an amount that part of the potassium sulphite remains in a suspended form. Preferably water is added such that 10-50% of the potassium sulphite is present in a suspended form and the reaction is carried out at a temperature from 90-160‹ C. Mixtures of substances such as potassium bisulphite or potassium pyrosulphite with potassium hydroxide may be used as they form potassium sulphite under the reaction conditions or potassium sulphite may be formed by direct reaction of sulphur dioxide with potassium hydroxide. The process may be carried out either by heating the mixture of methylene chloride and potassium sulphite or by heating the potassium sulphite suspension alone and then adding the methylene chloride. The product is used as an intermediate in the preparation of aluminium methionate and methionic acid. |
