PROCESS FOR CONCENTRATING BY FLOTATION LEAD AND SILVER IN PRODUCTS WHICH CONTAIN OXIDISED LEAD

摘要

1465070 Froth flotation processes ASTURIANA DE ZINC SA 25 Jan 1974 [27 Jan 1973] 03698/74 Heading B2H A finely divided product containing lead sulphate is subjected to flotation in an acidic medium containing a sulphurising agent e.g. sodium sulphide, to concentrate the lead sulphate in the floated product. Xanthates and/or dithiophosphates may be used as collectors and ammonium sulphate may also be added. Any silver present may be floated together with the lead sulphate or it may be floated off separately together with zinc and elemental sulphur in an earlier flotation process. In the latter embodiment, the silver is floated in an acidic medium in the presence of reagents which do not collect lead and a dispersant such as sodium silicate, and the residues from the silver flotation treated with sodium sulphide before passing to the flotation cells for the flotation of the lead sulphate. Each flotation process may be carried out in several stages.