METHOD FOR EXTRACTION AND SEPARATION OF RARE EARTH ELEMENTS

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A method for extracting and separating rare earth elements comprising providing a rare earth-containing ore or tailings, grinding the rare earth-containing ore to form powdered ore; leaching the powered ore with at least one mineral acid, forming a leach solution comprising at least one metal ion, rare earth elements and a solid material, separating the solid material from the leach solution to form aqueous-metal concentrate, precipitating the aqueous-metal concentrate to selectively remove the metal ion from the leach solution and obtain a precipitate of the rare earth elements; heating the precipitate of the rare earth elements in air to form oxide of the rare earth elements, mixing the oxide of the rare earth elements with an ammonium salt and heating in a dry air/nitrogen, forming a mixture of anhydrous rare earth salts in an aqueous solution, and separating the rare earth elements from the aqueous solution by means of an electrowinning process.