| 摘要 |
<p>PROBLEM TO BE SOLVED: To safely and stably clean a copper electrolytic soln. and to use the soln. circulatively by introducing hydrogen sulfide generated by bringing soda hydrosulfide into contact with a copper electrolytic soln. into a sulfurizing reaction tank in a sealed state, and bringing it into contact with a copper electrolytic soln. contg. copper, arsenic, antimony and bismuth. SOLUTION: The copper electrolytic soln. is supplied to two-stage sulfurizing reaction tanks 10 and 30 connected overflowably by a connecting pipe 1 from an electrolytic soln. introducing pipe 15, and is subjected to contact reaction by introducing gaseous hydrogen sulfide from gaseous hydrogen sulfide introducing pipes 11 and 31 while being stirred by stirrers 16 and 36. Thus copper, arsenic, antimony and bismuth incorporated in the copper electrolytic soln. are removed as sulfides, and nickel is removed as nickel sulfate by heating and concentrating the soln. The cleaned copper electrolytic soln. is used circulatively, furthermore a part thereof is added with soda hydrosulfide to generate hydrogen sulfide to be used for cleaning the copper electrolytic soln. It is preferable that the oxidation-reduction potential is controlled to -80 to -120 mV; and the pressure of hydrogen sulfide is controlled within±20% of the value between 0.01 and 0.05 MPa in the hydrogen sulfide generating tank.</p> |
