| 摘要 |
<p>Apparatus and methods for removing silver and copper ions from purge streams from silver replacement processes by separately electrowinning silver and copper where silver removal is first effected in an electrowinning cell (12) having a cathode/calomel reference electrode potential between -0.1 and -0.4 volts DC followed by copper removal effected in an electrowinning cell (28) having a cathode/calomel reference electrode potential less than -0.5 volts DC. By this method formation of copper (+1) is prevented in the presence of high concentrations of silver, thus minimizing precipitation of silver metal and formation of copper (+2).</p> |
