| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily concentrate and recover a noble metal incorporated slightly in a crude copper by electrically depositing copper on a cathode in powdery state and screening an obtained electrolytic copper powder, in an elecrorefining of the copper. SOLUTION: In the electrorefining of copper, the copper is deposited electrically on the cathode in powdery state by using the crude copper as an anode and a stainless steel plate or a titanium plate as a cathode and keeping a copper concn. of an electrolyte at the time of starting an electrolysis in less than about 40g/l. In such a case, a powdery electrodeposition matter is obtained when the electrolysis is executed while holding the copper concn. of the electrolyte in less than about 40g/l, keeping a liq. temp. in an order of 20-60 deg.C and a current density in more than limiting current density. The obtained electrodeposition powder is screened to separate into a copper powder low in noble metal content and a copper powder high in noble metal content. When the electrodeposition matter is made in powdery state, the matter is easily retreated by acid dissolving, etc., even if the matter which is hardly mechanically separated each other is produced.</p> |
