METHOD OF PREPARING CHLORINE-FREE POTASH FERTILISER Russian patent published in 2010 - IPC C05D1/02 

FIELD: chemistry.

SUBSTANCE: method involves treatment of potassium chloride with hydrofluosilicic acid, separation of potassium silicofluoride through filtration and thermal treatment at temperature lower than 975°C for not less than 1.0 hour to obtain silicon tetrafluoride and potassium fluoride. The silicon tetrafluoride is absorbed with water and the obtained hydrofluosilicic acid is returned to the process head. Potassium fluoride is treated with a calcium-containing component to obtain chlorine-free potash fertiliser. The calcium fluoride by-product can serve as an ideal raw material in production of hydrogen fluoride.

EFFECT: method enables creation of new technology of producing chlorine-free potash fertilisers which can be used as potassium-containing components for chlorine-free potassium-containing compound fertilisers.

3 cl, 1 ex