| abstract |
The present invention pertains to a method for recovering a rare metal salt, the method comprising: an acid treatment step for obtaining a rare metal-containing acidic aqueous solution by putting a material containing monovalent and polyvalent rare metals in contact with an acid aqueous solution; a separation step for obtaining permeated water containing the monovalent rare metal and non-permeated water containing the polyvalent rare metal from the rare metal-containing acidic aqueous solution by using a nanofiltration membrane satisfying a specific condition (1); and a concentration step for obtaining non-permeated water having a higher concentration of the monovalent rare metal and permeated water having a lower concentration than the permeated water in the separation step, by using a reverse osmosis membrane. |