METHOD FOR RECOVERING RARE EARTH METAL

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PROBLEM TO BE SOLVED : To provide a method for recovering rare earth metals by which rare earth metals can be selectively recovered in an easy and reliably manner from tin slag including rare earth metals, radioactive substances, iron, aluminum and the like. SOLUTION : A method for recovering rare earth metals includes : an inorganic acid leaching step 2 for performing water granulation or mechanical pulverization of tin slag discharged during tin smelting to dissolve the processed slag using an inorganic acid; a first oxidation and neutralization step 3 and a filtration step 4 for adding an oxidizing agent and a neutralizing agent to a dissolving solution of the tin slag, and adjusting the solution to a first condition, in which radioactive substances precipitate and rare earth metals and iron do not precipitate, to precipitate and remove radioactive substances; a second oxidation and neutralization step and filtration step 5, 6 for adding an oxidizing agent and a neutralizing agent to a neutral solution discharged through the first filtration step, and adjusting the solution to a second condition, in which iron precipitates and rare earth metals do not precipitate, to filter and remove the precipitated iron; and an organic solvent extraction step 7, a strip step 8, a precipitation step 9, a precipitation washing step 10, and a drying/firing step 11, for recovering the rare earth metals in the filtered neutral solution. COPYRIGHT : (C)2013, JPO&INPIT