Electrolytic silver refining process and apparatus

US4670115A · kind A · utility

Assignee

• Ogussa Osterreichische Gold-und Siber Scheideanstalt Scheid und Roessler Gessellschaft M.b.H. & Co. KG · AT

Inventors

• Adalbert Prior · Götzis, AT
• Rolf Marr · Zeltweg, AT
• Hans J. Bart · Zeltweg, AT

Key dates

• Filing date: Aug 22, 1984
• Grant date: Jun 2, 1987
• Expiry date: Aug 22, 2004

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25C1/20
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

In an electrolytic silver refining process, crude silver is anodically dissolved while refined silver is cathodically deposited and at the accompanying (impurity) metals are selectively extracted from the used (spent) electrolyte and transferred to an aqueous phase. The used electrolyte is enriched in silver and accompanying metals are cathodically deposited and thus removed from the electrolyte. For this purpose, a specific electrolysis cell is provided. The cell being preferably a diaphragm cell with an anionic diaphragm. The extraction of the accompanying metals is achieved by liquid membrane permeation, preferably combined with solvent extraction.