| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method to efficiently collect indium of high purity from indium inclusions containing various kinds of impurities. SOLUTION: Indium inclusions are leached with sulfuric acid to melt metals soluble in acid together with In, NaSH is added to the obtained leaching soln. while adjusting the oxidation-reduction potential to settle and remove the metals such as copper other than In. Sulfuric acid and NaSH are added to the obtained aqueous solution containing indium to settle and concentrate In as sulfide. In is selectively leached by blowing SO2 gas into the In sulfide under the acidity of sulfuric acid, and after adjusting the pH value, zinc powder is added to the obtained leaching soln. containing In to substitute and precipitate In sponge. The obtained In sponge is leached with hydrochloric acid, H2 S is blown into the leaching soln. to settle and remove the residual metallic ions such as Cd, and then, the metal indium of >=5N in purity is obtained through electrolytic winning.</p> |
