To provide a method where, in a wet type copper refining process including a chlorine leaching stage for a copper raw material containing a copper sulfide mineral, silver comprised in the copper raw material containing the copper sulfide mineral is concentrated into a precipitate, and is efficiently recovered.
Regarding the method for recovering silver, in a wet type copper refining process including a stage of subjecting a copper raw material containing a copper sulfide mineral to chlorine leaching or the like, at a stage where valuable metals are separated and recovered from an extraction remaining liquid in a solvent extraction stage, a reducing agent is added to the extraction remaining liquid containing copper ions and silver ions together with iron ions, the same is brought into cementation reaction as oxidation-reduction potential (based on a silver/silver chloride electrode) is controlled to 180 to 250 mV, the silver ions are preferentially reduced, so as to be separated and recovered as a precipitate (A), thereafter, the same is brought into cementation reaction as oxidation-reduction potential (based on a silver/silver chloride electrode) is controlled to -300 to 0 mV, and the copper ions and the remaining silver ions are reduced, so as to be separated and recovered as a precipitate (B).
COPYRIGHT: (C)2007,JPO&INPIT
Keiji Kudo
Masaki Imamura
| JP2005060813A | ||||
| JP2005232594A | ||||
| JP8176693A |