GB415972A - Improvements in or relating to the preparation of fluosilicates - Google Patents

Abstract

Difficulty soluble fluosilicates, such as sodium fluosilicate, are dispersed by treatment with solutions containing metal salts, the cations of which form fluosilicates of greater water solubility than the starting materials employed, such as salts of magnesium and calcium, in quantities insufficient for double decomposition with the difficulty soluble fluosilicates together with organic water soluble compounds containing free hydroxyl groups, and weak bases, such as ammonia or organic bases. The peptising process may be accelerated by heating the peptising liquid to a temperature below its boiling point, or by mechanical disintegration of the starting materials or by a combination of both processes. The dispersions are flocculated by dilution or heating or both. Concentrated solutions containing up to 50 per cent of the fluosilicates may be used for the manufacture of enamels, or for pest-destroying purposes. For this latter application, the concentrated solutions may be diluted and substances such as sugar molasses or spent sulphite liquor may be p added. The dry products may also be used for pest destroying purposes and inert diluents such as coal ash, peat ash or kaolin may be added. Powdered calcium arsenate may also be added. According to examples: (1) 100 pts. by weight of sodium fluosilicate are heated for 3 hours at 70 DEG C. with a solution consisting of 100 pts. water, 10 pts. magnesium sulphate, 30 pts. glycerine and 3 pts. aniline; (2) 100 pts. by weight of sodium fluosilicate are treated for 1 hour at 60 DEG C. in a colloid mill with a solution consisting of 100 pts. water, 8 pts. calcium chloride and 35 pts. of 96 per cent ethyl alcohols and 5 pts. of 25 per cent ammonia are gradually added to the mass.ALSO:Difficultly soluble fluosilicates, such as sodium fluosilicate, are dispersed by treatment with solutions containing metal salts, the cations of which form fluosilicates of greater water solubility than the starting materials employed, such as salts of magnesium and calcium, in quantities insufficient for double decomposition with the difficultly soluble fluosilicates together with organic water soluble compounds containing free hydroxyl groups, and weak bases, such as ammonia or organic bases. The peptizing process may be accelerated by heating the peptizing liquid to a temperature below its boiling point, or by mechanical disintegration of the starting materials or by a combination of both processes. The dispersions are flocculated by dilution or heating or both. Concentrated solutions containing up to .50 per cent of the fluosilicates may be used for pest-destroying purposes. For this latter application, the concentrated solution may be diluted and substances such as sugar molasses or spent sulphite liquor may be added. The dry products may also be used for pest-destroying purposes and inert diluents such as coal ash, peat ash or kaolin may be added. Powdered calcium arsenate may also be added. According to examples (1) 100 parts by weight of sodium fluosilicate are heated for 3 hours at 70 DEG C. with a solution consisting of 100 parts water, 10 parts magnesium sulphate, 30 parts glycerine and 3 parts aniline. (2) 100 parts by weight of sodium fluosilicate are treated for 1 hour at 60 DEG C. in a colloid mill with a solution consisting of 100 parts water, 8 parts calcium chloride and 35 parts of 96 per cent ethyl alcohol and 5 parts of 25 per cent ammonia are gradually added to the mass.