Method of recovering rare

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PROBLEM TO BE SOLVED : To provide a recovery method of a rare earth element capable of recovering the rare earth element safely, less in used amount of acid, good in separability of the rear earth element and iron, and less in load of liquid waste disposal.SOLUTION : A recovery method of a rare earth element includes the steps of : performing alkali exudation of alkali silicate which is a mixture of alkali metal oxide and silica and contains a rear earth element to elute silica; performing acid dissolution of the solid-liquid separated alkali exudated slag to elute the rare earth element and residue silica; adding alkali to the acid dissolved liquid to deposit silica and remain the rare earth element in a liquid component; and recovering the rare earth element from the liquid solution subjected to the solid-liquid separation. For example, alkali silicate slag generated in Fe-Si melting treatment where alkali silicate containing the rare earth element is molten under an inert gaseous atmosphere by adding an Fe-Si alloy, an alkali metal source and silica to a rear earth element-containing waste, is used.SELECTED DRAWING : Figure 1