METHOD OF OBTAINING CALCIUM FLUORIDE FROM FLUORINE-CONTAINING SOLUTIONS Russian patent published in 2016 - IPC C01F11/22 

FIELD: chemistry.

SUBSTANCE: method of obtaining calcium fluoride from fluorine-containing solutions includes processing claimed solutions with calcium hydroxide with the following separation of solution and pulp and extraction of calcium fluoride. As fluorine-containing solution applied is solution, obtained in leaching of solid finely-dispersed fluorocarbon-containing wastes of aluminium electrolytic production in form of coal foam flotation tailings. Wastes are supplied to processing in ratio 1:(6-10) relative to 2-2.5% solution of sodium hydroxide. Processing is carried out at temperature of solution to be leached 75-80°C. Obtained fluorine-containing solution is supplied to processing with calcium hydroxide, taken in ratio (1.8-2.1):1 relative to content of fluorine in solution. Temperature of fluorine-containing solution is 40-55°C. Obtained calcium fluoride is washed with water at temperature 80-90°C for 20-40 minutes.

EFFECT: invention makes it possible to utilise fluorocarbon-containing wastes of aluminium electrolytic production with obtaining calcium fluoride and byproducts.

3 cl, 1 dwg, 3 tbl, 1 ex