METHOD OF PRODUCING HIGH-PURITY POTASSIUM DIHYDROPHOSPHATE Russian patent published in 2020 - IPC C01B25/30 C01D13/00 C01B25/32 C01F11/00 C30B29/14 

FIELD: technological processes.

SUBSTANCE: invention relates to purification of potassium dihydrophosphate, which in the form of large monocrystals is used in laser installations of high peak power. Method of producing high-purity potassium dihydrophosphate involves dissolving initial potassium dihydrophosphate in distilled water while heating. Alkaline agent is added to the obtained solution. Alkaline agent used is calcium hydroxide in form of an aqueous suspension which is added while stirring to heated to 85–95 °C solution of potassium dihydrophosphate in an amount corresponding to the weight ratio of calcium hydroxide to potassium dihydrophosphate equal to 1:(13–20). Separated from solution precipitated calcium hydrophosphate CaHPO_4. Solution is cooled to room temperature with constant stirring. Crystals of the end product are separated by filtration and washed with distilled water.

EFFECT: invention enables to obtain highly pure potassium dihydrophosphate containing impurities of aluminum, iron, chromium and titanium at a level of less than or equal to 5⋅10^-6 wt%.

1 cl, 3 ex