Process for the recovery of metals from used nickel/metal/rare earth hydride storage batteries

US6110433A · kind A · utility

Assignee

• Varta Batterie Aktiengesellschaft · DE

Inventors

• Klaus Kleinsorgen · Kelkheim, DE
• Uwe Kohler · Kelkheim, DE
• Alexander Bouvier · Krumpendorf, AT
• Andreas Folzer · Althofen, AT

Key dates

• Filing date: Jun 16, 1997
• Grant date: Aug 29, 2000
• Expiry date: Jun 16, 2017

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02W30/84
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The invention relates to a process for recovering metals from used nickel/hydride storage batteries, in which storage battery scrap has been mechanically comminuted and divided into at least a coarse fraction and a fine fraction capable of being treated separately from one another. The process comprises the steps of digesting and dissolving the fine fraction with a mixture of sulfuric acid and hydrogen peroxide, performing a double sulfate precipitation of the rare earths by raising the pH, performing a precipitation of the iron and of the aluminum by further raising the pH, performing a solvent extraction of other metals to separate nickel and cobalt which remain in the aqueous phase from the other metals which are extracted into the organic phase. Optionally, the nickel and the cobalt can be separated from each other and, if desired, the mixed-metal rare earth component which has been recovered can be melted together with cobalt and nickel alloy for the fabrication of new batteries.