The extraction of gold from sulfide concentrates into molten lead

The results of investigation of the extraction of gold from mineral sulfide ore into molten lead at low temperatures (350–550°C) are given. The questions of solubility of Au in Pb in the mentioned temperature range and the kinetics of dissolution of metal are analyzed. The condition that determines extraction of gold is the presence of a processing medium, which provides the decomposition of carrier minerals of gold and prevents the anodic oxidation of the lead alloy. The alkali melt is suggested to be used as such a medium. The procedures of preparation of sulfide Au-containing concentrates to the extraction associated with obtaining the cakes and their charging into the extraction apparatus are considered. Extraction proceeds in the transient region. In this case, high characteristics of extraction are achieved. The reasons for collector dispersion, which conditions the losses of gold, are established.