摘要 |
<p>A process for removing chlorine from a solution of zinc sulfate, in which the pH of the solution is reduced to below 2.6 with sulfuric acid. Cupric ions are established in the solution in an amount such that after removal of the chlorine by precipitation as cuprous chloride, there remains an excess of cupric copper in the solution which is greater than 0.5 g/l. The cupric ions can be added by adding cupric sulphate and zinc powder, or cupric salt and metallic copper, or cupric copper followed by cuprous oxide. The cuprous chloride precipitate is collected and washed and treated with sodium hydroxide in an amount to raise the pH to more than 7, thereby to precipitate cuprous oxide which is separated by filtration.</p> |