| 摘要 |
<p>Zinc sulphate solution containing copper, cadmium and cobalt impurities, is in a first stage, treated with zinc dust and an antimony and/or arsenic compound so as to form a cement containing essentially all the copper and cadmium and a portion of the cobalt. This cement is separated from the partially purified solution, which is in a second stage, treated with zinc dust and an antimony and/or arsenic compound to form a cement containing essentially metallic zinc as well as the remaining cobalt and other incidental impurities. This cement is separated from the purified solution and at least the major portion recycled to the first stage. <IMAGE></p> |
