Fully automatic current control for metal depletion cells

US5362369A · kind A · utility

Assignee

• Heraeus Elektrochemie GmbH

Inventors

• Max Mayr · Alzenau, DE
• Wolfgang Blatt · Wächtersbach, DE
• Harri Heinke · Niederrodenbach, DE

Key dates

• Filing date: Sep 3, 1992
• Grant date: Nov 8, 1994
• Expiry date: Sep 3, 2012

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25C7/06
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

An electrolytic cell, for demetallization of a solution containing metal ions, has a hydrogen sensor connected to a control and monitoring unit which controls the intensity of current applied across the cell's electrodes. Whenever the hydrogen concentration above the solution surface in the cell reaches a predetermined undesirably high level, the control unit makes a stepwise reduction in the applied current. This stepwise reduction continues until the ions in the solution are depleted to a predetermined level, at which point the solution is replaced.