| 摘要 |
<p>This invention relates to the recovery of platinum group metals and gold and silver from scrap and residues and also to the separation of silver from the other precious metals referred to. In more detail the process for the recovery of platinum group metals, silver and gold from precious metal containing residue comprises the following steps: (a) smelting the said precious metal containing residue with leach residue and a flux to produce (i) a slag containing FeO, CaO and SiO2 and (ii) a copper matte phase containing Ni,Fe,S, and the platinum group metals, Au, Ag, Se and Te. (b) removing, if necessary, any excess of the elements iron or nickel or compounds thereof from the matte phase produced by step (a) by oxidation thus converting the said elements or compounds thereof to their respective oxides which then report to the slag phase, (c) contacting the matte phase produced by step (a) or the said matte phase after oxidation step (b) with one or more metals selected from the group Cu, Ni and Fe so as to produce a separate immiscible metallic phase containing platinum group metals, silver and gold, (d) optionally recirculating the said separate metallic phase produced by step (c) to contact a separately produced matte phase produced by a step (a) or by steps (a) and (b) so as to at least partially redistribute the silver present out of the metallic phase, and, (e) recovering silver from the matte phase and the platinum group metals, gold and the proportion of silver which remains from the metallic phase.</p> |
