Separation and recovery of Cu and As from copper electrolyte through electrowinning and SO_2 reduction

Cu and As were separated and recovered from copper electrolyte by multiple stage electrowinning, reduction with SO2and evaporative crystallization. Experimental results showed that when the current density was 200 A/m2, the electrolyte temperature was 55 °C, the electrolyte circulation rate was about 10 mL/min and the final Cu concentration was higher than 25.88 g/L, the pure copper cathode was recovered. By adjusting the current density to 100 A/m2 and the electrolyte temperature to 65 °C, the removal rate of As was 18.25% when the Cu concentration decreased from 24.69 g/L to 0.42 g/L. After As（V） in Cu-depleted electrolyte was fully reduced to As（Ⅲ） by SO2, the resultant solution was subjected to evaporative crystallization, then As2O3 was produced, and the recovery rate of As was 59.76%. The cathodic polarization curves demonstrated that both Cu2＋ concentration and As（V） affect the limiting current of Cu2＋ deposition.

金铜冶炼高砷烟尘酸浸液铜砷分离回收工艺研究

针对高砷白烟尘酸浸液中的铜砷分离回收进行了工艺研究,采用沉铜法分离铜,沉铜液用二氧化硫还原结晶。试验结果表明:在85℃以上加入沉铜剂反应2h可实现铜的分离,铜的回收率达98%以上,沉铜液中的砷通入二氧化硫还原,结晶温度为20℃时,砷的回收率70%左右。该工艺为高砷烟尘酸漫液中的铜砷分离及回收提供了较为可靠的处理思路。