METHOD FOR RECOVERING RARE EARTH

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PROBLEM TO BE SOLVED : To provide a method for recovering rare earths where the intrusion of impurities is prevented, and large quantities of rare earths are recovered at a low cost. SOLUTION : The method for recovering rare earths comprises : a first stage where rare earth magnet scrap produced from either or both of the production process of a rare earth magnet and the city is fed to sulfuric acid, and rare earths in the rare earth magnet scrap are dissolved in the sulfuric acid; a second stage where components which do not dissolve in the sulfuric acid are removed so as to obtain a rare earth-containing solution; a third stage where an ammonia aqueous solution is added to the solution; a fourth stage where the ammonium salt of rare earth-sulfuric acid produced by the addition of the ammonia aqueous solution is crystallized; and a fifth stage where the crystals of the ammonium salt of rare earth-sulfuric acid produced in the fourth stage are recovered. COPYRIGHT : (C)2006, JPO&NCIPI