copper ore electrowinning process

A process and apparatus for electrowinning a high purity copper from an aqueous pregnant liquor acid electrolyte at high efficiency, and high current density in the presence of impurities. Electrolyte is circulated through an external loop system and upwardly between the anodes and cathodes. SO.sub.2, iron, and acid are added to the electrolyte in the external loop to maintain an SO.sub.2 ...