Process for purifying an aqueous solution of N-methyl-morpholine N-oxide

US5053138A · kind A · utility

Assignee

• LENZING AKTIENGESELLSCHAFT · AT

Inventors

• Dietmar Korger · Gmunden, AT
• Dieter Eichinger · Vöcklabruck, AT
• Stephan Astegger · Vöcklabruck, AT
• Karin Weinzierl · Vöcklabruck, AT
• Johann Manner · Vöcklabruck, AT

Key dates

• Filing date: Oct 11, 1990
• Grant date: Oct 1, 1991
• Expiry date: Oct 11, 2010

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P70/62
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

There is disclosed a process for purifying aqueous solutions of N-methyl-morpholine N-oxide (NMMO), such as spinning bath solutions incurred in the production of cellulose products, in which process the solutions to be purified are contacted with an anion exchanger and the purified solutions are separated from the anion exchanger. The process is carried out in one step and the anion exchanger, as functional groups, exclusively contains quaternary tetraalkylammonium groups of the formulae EQU --CH.sub.2 --N.sup..sym. (CH.sub.3).sub.3 X.sup..crclbar. or --CH.sub.2 --N.sup..sym. [(CH.sub.3).sub.2 (CH.sub.2 OH)]X.sup..crclbar. wherein X.sup..crclbar. represents the anion of an inorganic or organic acid. After this, the anion exchanger is regenerated with an aqueous acidic solution.