| 摘要 |
<p>PROBLEM TO BE SOLVED: To simply recover a high purity metal indium from an indium- containing material by deoxidizing an indium dissolved solution and cementating with metal indium to efficiently remove tin of a coexisting element. SOLUTION: The indium dissolved solution is obtained by dissolving an indium-containing material such as an ITO target scrap in hydrochloric acid or a mixed acid of hydrochloric acid with sulfuric acid. The dissolved solution is introduced into a closed vessel and the dissolved oxygen in the solution is discharged outside of the system by introducing an inert gas into the dissolved solution to reduce the dissolved oxygen in the solution to <=10ppm. A metal indium plate is charged in the dissolved solution to perform the cementation (substitution and deposition) of an impurity metallic ion. As a result, the impurity metallic ion more noble than indium such as tin, copper or lead is reduced and deposited by the metallization in company with the dissolution of indium by ionizing. Indium is recovered by electrolysis using the dissolved solution after filtered as the electrolyte, the metal indium plate as a cathode and a carbon plate as an anode.</p> |
