Process for the purification of mixtures of toluenediisocyanate incorporating a dividing-wall distillation column

US7118653B2 · kind B2 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Bill Brady · Goldkronach, DE
• Friedhelm Steffens · Leverkusen, DE
• Berthold Keggenhoff · Krefeld, DE
• Kai Verkerk · Hilden, DE
• Gerhard Ruffert · Leverkusen, DE

Key dates

• Filing date: Jun 9, 2003
• Grant date: Oct 10, 2006
• Expiry date: Feb 6, 2024

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S203/11
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Process for the purification of toluenediisocyanate from a crude distillation feed which includes toluenediisocyanate, an organic solvent and less than 2% by weight phosgene by separating the crude distillation feed in a dividing-wall distillation column into at least four product fractions P1–P4.