摘要 |
<p>Zinc and manganese are recovered from a soln. contg. 25 g/l sulphuric acid and derived from dissolution of Zn and Mn values using recycle electrolyte, by (a) electrolysing (part of) the purified soln., heated to >=70 degrees C, to produce battery grade MnO2 at the anode and Zn at the cathode and (b) feeding the electrolyte, contg. 75g/l H2SO4, from step (a) to the main Zn electrowinning circuit together with any soln. not subjected to step (a). The process is controlled so that the amt. of MnO2 recovered in step (a) together with that plated out in step (b) and lost in any other way is equal to the amt. of Mn added to the soln. during the reuse of spent electrolyte in dissolving Zn and Mn.</p> |