| abstract |
(57) [Problem] To provide a method capable of recovering high-purity indium from indium-containing substances such as ITO target waste in a simple process. SOLUTION: An indium-containing substance is dissolved with hydrochloric acid, an alkali is added to the solution to neutralize the solution to a predetermined value within a range of 0.5 to 4, and a predetermined metal in the solution is dissolved. The ions are precipitated and removed as hydroxides, and then hydrogen sulfide gas is blown into the solution to precipitate and remove metal ions harmful to electrolysis in the next step as sulfides. Is electrowinned. By this method, 99.999 purity from ITO target waste can be obtained. % Of indium can be recovered. |