Method of removing Cr(VI) ions from an aqueous electrolyte solution

US11389887B2 · kind B2 · utility

Assignee

• MTU Aero Engines AG · DE

Inventors

• Nicole Feiling · Munich, DE
• Max Niegl · Munich, DE
• Martin Koenitzer · Munich, DE
• Norbert Rast · Munich, DE
• Rudolf Hill · Langenfeld, DE
• Dieter Mauer · Lollar, DE

Key dates

• Filing date: Jan 22, 2020
• Grant date: Jul 19, 2022
• Expiry date: Jan 22, 2041

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C02F2103/16
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

The invention relates to a method for removing Cr(VI) ions from an aqueous electrolyte solution, particularly an electrolyte solution for electrochemical metal machining, which comprises the reduction of Cr(VI) to Cr(III) with Fe(II) ions. The Fe(II) ions are added to the electrolyte solution in the form of an aqueous salt solution which has been brought into contact with an ion exchange resin loaded with Fe(II) ions. The invention further relates to a device (1) for electrochemical machining of a workpiece (2) by means of an aqueous electrolyte solution (6), which has an ion exchanger (11) which has been loaded with an ion exchange resin charged with Fe(II) ions.