| 摘要 |
<p>In a process for treatment of a leach solution containing nickel, cobalt and zinc, in which the nickel is partially precipitated by treatment with a reducing gas under pressure, and % the remainder of the nickel together with the zinc is then precipitated as complex ammonium sulphates which are recycled, the composition of the solution is adjusted prior to the initial nickel separation so that after that separation the mol ratio of zinc: nickel lies in the range 0.5 : 1 to 5:1. Adjustment of the zinc content is effected by addition of zinc sulphate or by a controlled precipitation of zinc sulphide from the acidified solution. The zinc nickel ammonium sulphate may be recycled to the zinc content adjustment stage, or may be added to the feed solution between that stage and the nickle precipitation stage, in which case a suitable allowance is made at the adjustment stage.</p> |
