METHOD OF PREPARING POTASSIUM SILICON FLUORIDE Russian patent published in 2001 - IPC

FIELD: preparation of silicon fluoride salts, more particularly preparation of potassium silicon fluoride. SUBSTANCE: method comprises premixing fluosilicic acid with potassium silicon fluoride solution containing at least 3 g/l thereof and subsequently feeding solution of potassium salts having temperature of 90-95 C into mixture of acid and potassium silicon fluoride or simultaneously feeding said mixture and solution of potassium salt into reactor. In this case, pH value of mixture of solutions should not exceed 3. Potassium salts include potassium chloride, potassium carbonate or mixture thereof. EFFECT: increased yield of product and improved settling and filtration characteristics thereof. 2 cl, 4 ex, 1 tbl