Patent · US Expired

Method for concentrating precious metals contained in leaching residue discharged from copper hydrometallurgical process

US7422621B2 · kind B2 · utility

6Cited by
10References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 22, 2004
Grant dateSep 9, 2008
Priority date
Expiry dateFeb 15, 2026

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A method for concentrating precious metals contained in the leaching residue discharged from a copper hydrometallurgical process by removing pyrite from the residue. A method for concentrating precious metals in the leaching residue containing pyrite, elementary sulfur, precious metals and gangue, discharged from a copper hydrometallurgical process which comprises steps of leaching in an acidic, aqueous solution, reducing the copper-containing leaching liquor and electrolysis for copper recovery to treat copper sulfide ores, comprising (1) pyrolysis step in which the leaching residue is thermally treated at 550.degree. C. or higher in a non-oxidative atmosphere, to produce the calcined ore containing pyrrhotite, precious metals and gangue, and (2) a re-leaching step in which the calcined ore is re-leached in an acidic, aqueous solution, to be separated into the re-leaching residue and iron-leached liquor, the former containing elementary sulfur, precious metals and gangue.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.