Process for recovering silver from residues containing silver and lead

US4127639A · kind A · utility

Assignee

• Duisburger Kupferhutte

Inventors

• Norbert L. Piret · Duisburg, DE
• Wilhelm Roever · Duisburg, DE

Key dates

• Filing date: Jun 11, 1976
• Grant date: Nov 28, 1978
• Expiry date: Jun 11, 1996

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P10/20
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Aqueous lead solutions obtained by hot chloride leaching of residues containing lead and silver ore are subjected to selective precipitation of the silver as silver sulphide, with e.g. hydrogen sulphide. The silver can then be recovered in a known manner. Lead can be precipitated from the remaining solution as a basic salt also in a known manner. If the initial residue contains copper, it is also precipitated as sulphide. The copper sulphide can be separated from the precipitate by selectively dissolving the copper with sulphuric acid under an elevated oxygen pressure. Elemental sulphur is formed and the silver sulphide can be separated from the elemental sulphur in a known manner.