Methods for producing or purifying onium hydroxides by means of electrodialysis

US6527932B1 · kind B1 · utility

Assignee

• BASF SE

Inventors

• Jörg Botzem · Schifferstadt, DE
• Reiner Kober · Neheim, DE
• Markus Frede · Eppelheim, DE

Key dates

• Filing date: Jun 7, 2001
• Grant date: Mar 4, 2003
• Expiry date: Jun 7, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C209/68
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Methods of preparing or purifying onium hydroxides of the elements N, S or P by electrodialysis involve an electrodialysis apparatus comprising one or more cell units, each cell unit comprising a bipolar membrane and an anion-selective membrane, and a bipolar membrane or a cation-selective membrane being located on the anode side between the last anion-selective membrane and the anode.