GB342931A - Process of manufacturing fertilisers - Google Patents

Abstract

Microcosmic salt, and a mixture of ammonium and potassium chlorides are obtained by treating a solution of sodium and potassium chlorides, such as may be obtained from sylvinite, with phosphoric acid and ammonia, either in the free state or in combination, in the ratio of one molecule acid and two molecules ammonia to each molecule of sodium chloride. Microcosmic salt, precipitated, if necessary by cooling, is separated and ammonium and potassium chloride are obtained from the mother liquor. In an example, phosphoric acid is added to previous mother liquor, and the solution is treated below 50 DEG C. with ammonia. The solution is cooled until the separation of the chlorides commences, when microcosmic salt is separated. Crushed sylvinite is added to the mother liquor, the solution is cooled strongly, and the mixture of ammonium and potassium chlorides ("Potazote") containing, say, 3 per cent of microcosmic salt is separated. The products may be employed as fertilizers. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the production of ammonium and potassium chlorides separately by the addition of suitable precipitants, or by fractional crystallization. The chlorides may be obtained free from microcosmic salt by passing excess of ammonia into the boiling solution to precipitate (NH4)6 Na(PO4)2. This subject-matter does not appear in the Specification as accepted.ALSO:Microcosmic salt, and a mixture of ammonium and potassium chlorides which may be employed as fertilizer, are obtained by treating a solution of sodium and potassium chlorides, such as may be obtained from sylvinite, with phosphoric acid and ammonia, either in the free state or in combination, in the ratio of one molecule acid and two molecules ammonia to each molecule of sodium chloride. Microcosmic salt, precipitated, if necessary by cooling, is separated and the mixture of ammonium and potassium chloride is obtained from the mother liquor. In an example, phosphoric acid is added to previous mother liquors, and the solution is treated below 50 DEG C. with ammonia. The solution is cooled until the separation of the chlorides commences, when microcosmic salt is separated. Crushed sylvinite is added to the mother liquor, the solution is cooled strongly, and the mixture of ammonium and potassium chlorides ("Potazote") containing, say, 3 per cent of microcosmic salt is separated.