METHOD FOR APATITE ORE AND CONCENTRATE PROCESSING

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FIELD : chemistry. SUBSTANCE : method comprises apatite acidolysis using nitric acid followed by freezing out and separation of calcium nitrate tetrahydrate crystals, precipitation and separation from nitrophosphate fluoride solution, neutralisation of the purified solution, precipitation of phosphate concentrate of rare earth elements (REE) and radionuclides by cooling down the solution to minus 20°C, the precipitated calcium nitrate tetrahydrate crystals are separated from the mother solution at minus 20°C, the nitrophosphate solution is neutralised by calcium carbonate or calcium hydroxide solution at pH 2.5; precipitate from the solution of rare earth phosphates and radionuclides is separated, extraction of REE and radionuclides is carried out in a cascade of centrifugal extractors using an organic extraction solvent (tributyl phosphate) at a concentration of 30 to 100%. The extraction solution may be presaturated with nitric acid of the same concentration as the process solution. EFFECT : high extraction rate of REE and radionuclides from apatite ore and concentrate with low residual activity, using a simplified process, reduced energy consumption and labour intensity. 3 cl