Method for producing isocyanates

US7112694B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Andreas Woelfert · Bad Rappenau, DE
• Christian Mueller · Wiesbaden, DE
• Eckhard Stroefer · Mannheim, DE
• Andreas Brodhagen · Schifferstadt, DE

Key dates

• Filing date: May 19, 2003
• Grant date: Sep 26, 2006
• Expiry date: May 19, 2023

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C263/10
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a continuous process for preparing isocyanates by reacting primary amines with phosgene, wherein the reaction is carried out in a cascade of at least two tube reactors and the gas phase formed in the reaction is separated off in a phase separator after each reactor and only the liquid phase is passed to the next reactor or to product purification and the reaction volume of the first tube reactor is only a fraction of the total reaction volume.