METHOD FOR PROCESSING FLUORIDE RARE-EARTH CONCENTRATE

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FIELD : chemistry. SUBSTANCE : invention relates to a method for processing fluoride-containing rare-earth element concentrates (REE) and can be used in hydrometallurgy. Yttrium fluorite concentrate, containing wt % : 40 F, 13.15 ΣTr2O3, 0.16 TiO2, 66.4 CaO, is treated with hydrofluoric acid with a concentration of 5-10 g/l at a temperature of 60-80°C for 4-8 hours in the presence of sulfoxide cationite with the transfer of rare-earth elements, calcium and thorium, into the sulfoxide cationite, and fluorine into the acidic solution. Sulphocationite is taken in an amount of 265-300% of the stoichiometrically necessary for the sorption of metal cations contained in the concentrate. Sulfocationite is then separated from the acidic solution and regenerated with a solution of ammonium nitrate to obtain a desorbate. The latter is subjected to stepwise neutralisation by an ammonium compound with successive precipitation and separation of thorium, a rare-earth concentrate and a calcium-containing precipitate. EFFECT : expansion of the raw material base for the production of rare-earth elements with a high degree of extraction of rare-earth elements into concentrate, a high degree of purification from fluorine and thorium, and a reduction in the amount of generated waste. 2 cl, 4 ex