GB787463A - Process for the production of salts of 3-hydroxypropane-1-sulphonic acid - Google Patents

Abstract

Salts of 3-hydroxypropane-1 sulphonic acid are produced by reacting allyl alcohol in the presence of finely distributed oxygen or an oxygen-containing gas or an oxidizing agent with an excess, preferably 20 to 60 per cent excess, of a neutral or slightly alkaline sulphite solution and neutralizing the alkali liberated during the reaction by continuous addition of acid, e.g. dilute sulphuric acid. Sodium, potassium and ammonium sulphites are specified. The oxidizing agent may be a substance which can evolve oxygen, e.g. a peroxide. Preferably, the allyl alcohol is added slowly to the total quantity of sulphite at temperatures below 100 DEG C. with cooling if necessary, room temperature being preferred. Higher temperatures may be used under pressure. The allyl alcohol may be diluted with water, e.g. as an azeotropic mixture. The speed of stirring, and the rate of delivery and quantity of oxidizing gas are adjusted to obtain maximum yield. In an example, sulphur dioxide is passed into caustic potash solution to give a solution of potassium sulphite (pH 7-8), an azeotropic allyl alcohol-water mixture is then added slowly accompanied by vigorous stirring while a current of air is introduced and the pH is maintained at 7 to 8 by continuous addition of dilute sulphuric acid; potassium sulphate is filtered off, the filtrate evaporated to dryness, and the product is recrystallized from alcohol. Specification 782,093 is referred to.