摘要 |
Residues containing lead as lead sulphate and silver in the form of native silver or silver chloride, sulfide or sulphate, as well as silver complexes with other metals, and resulting from the roasting and leaching of sulfide concentrates containing lead, zinc, copper, and silver are treated to produce a high grade lead and silver product containing lead predominantly as calcium plumbate in a process wherein the residue is leached with brine, the resultant leach solution treated with lime to precipitate lead as oxychlorides, and the resultant lime-oxychloride precipitate is calcined to produce a mixture of calcium orthoplumbate and lead oxide. Residual chloride can be washed easily from this product which may then be treated in a lead blast furnace to recover lead and associated silver in their elemental state. |