Process for the preparation of isocyanates

US7645900B2 · kind B2 · utility

Assignee

• Bayer MaterialScience AG · DE

Inventors

• Wolfgang Lorenz · Dormagen, DE
• Matthias Boehm · Leverkusen, DE
• Richard Adamson · Leichlingen, DE
• Friedhelm Steffens · Leverkusen, DE
• Anke Hielscher · Cologne, DE

Key dates

• Filing date: Feb 17, 2009
• Grant date: Jan 12, 2010
• Expiry date: Feb 17, 2029

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C263/20
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for the preparation of isocyanates by reacting the appropriate amines with phosgene, condensing the gas mixture thereby obtained, stripping the liquid phase thereby obtained and returning the solvent so retained in liquid form to the reaction stage. The gaseous constituents are then purified further in an absorption process.