| 摘要 |
<p>PURPOSE:To simply and effectively remove impurities such as Sb, Bi and As from a copper electrolytic soln. acidified with sulfuric acid at a low cost without changing the concns. of copper and sulfuric acid in the electrolytic soln. by cooling the electrolytic soln. and carrying out solid-liq. separation. CONSTITUTION:When copper is electrolytically refined, impurities such as Sb, Bi and As in a crude copper plate as the anode dissolve in a copper electrolytic soln. acidified with sulfuric acid in accordance with the progress of electrolysis. The electrolytic soln. contg. at least one kind of impurity such as Sb, Bi or As is cooled to <=about 45 deg.C, preferably about 20-40 deg.C optionally after oxidation treatment and the cooled soln. is allowed to stand for >=about 24hr, preferably >=about 48hr. Sb, Bi or As in the electrolytic soln. forms a white precipitate and this precipitate is separated and removed. The purified electrolytic soln. undergoes no change in the concns. of copper and sulfuric acid. The precipitate can be used as starting material for producing Sb, Bi or As as it is because of a low copper content.</p> |
