METHOD FOR RECOVERING RARE EARTH ELEMENT

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PROBLEM TO BE SOLVED : To provide a recovering method for rare earth elements in which rare earth elements can be recovered efficiently and with high recovery rate without using an expensive drug, solvent, and the like. SOLUTION : A water soluble salt other than a sulfate ion is allowed to coexist in an aqueous solution containing a rare earth element, and then thereto is added an alkali metal sulfate to form a sulfate double salt precipitate of the rare earth element. The water soluble salt is a salt which can decrease free water in the aqueous solution containing the rare earth element by hydration. It is a salt including one or more selected from chloride, perchlorate, chlorate, bromate, bromide, periodate, iodate, iodide, and nitrate, and having a divalent positive ion. It is preferably nickel chloride. It is allowed to coexist at a negative ion concentration of 4 to 10 mol/l. The alkali metal sulfate is preferably sodium sulfate, and the sulfate ion concentration in the aqueous solution is increased to 50 g/l or more by its addition. COPYRIGHT : (C)2013, JPO&INPIT