Obtaining very pure maleic anhydride from crude maleic anhydride

US4961827A · kind A · utility

Assignee

• BASF SE

Inventors

• Dieter Zimmerling · Ludwigshafen, DE
• Johannes E. Schmidt · Ludwigshafen, DE
• Rolf Seubert · Bischofswerda, DE
• Karl Fischer · Burns Lake, CA
• Friedrich Sauer · Grünstadt, DE

Key dates

• Filing date: Jan 22, 1986
• Grant date: Oct 9, 1990
• Expiry date: Jan 22, 2006

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S203/20
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Very pure maleic anhydride having a stable color is obtained by fractional distillation of crude maleic anhydride by a method in which the maleic anhydride vapor separated off from low boilers and high boilers is partially condensed so that from 0.5 to 15% by weight of the maleic anydride vapor is separated off from the vapor phase as a liquid precondensate, and the remaining very pure maleic anhydride vapor is then completely condensed.