Process for the isolation of noble metals

US4925485A · kind A · utility

Assignee

• SKW Trostberg Aktiengesellschaft · DE

Inventor

• Reinhold Schulze · Hamburg, DE

Key dates

• Filing date: Dec 26, 1984
• Grant date: May 15, 1990
• Expiry date: Dec 26, 2004

Classification

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

Abstract

The present invention involves the isolation or leaching of noble metals from materials containing noble metals, e.g. ores, by treating the noble metal- containing materials with a cyclic thiourea derivative under acid pH conditions. Removal is effected by adsorption onto charcoal or by an ion exchanger, for example. Preferred cyclic thioureas are N,N'-ethylenethiourea and N,N'-propylenethiourea and the acid pH conditions may be achieved by sulfuric acid or hydrochloric acid solutions containing 0.01 to 2.0% by weight of the cyclic thiourea.