Method for producing isocyanates

US8193385B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Matthias Kloetzer · Kröppen, DE
• Heinrich-Josef Blankertz · Hamm (Sieg), DE
• Gunter Georgi · Schwarzheide, DE
• Eckhard Stroefer · Mannheim, DE
• Volker Krase · Schwarzheide, DE
• Gerhard Schulz · Ludwigshafen, DE
• Andreas Warzecha · Schwarzheide, DE

Key dates

• Filing date: Aug 8, 2007
• Grant date: Jun 5, 2012
• Expiry date: Dec 6, 2028

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C2601/14
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a multistage process for the continuous preparation of organic, distillable isocyanates, preferably diisocyanates, particularly preferably aliphatic or cycloaliphatic diisocyanates, by reaction of the corresponding organic amines with urea and alcohols to liberate ammonia and form low molecular weight monomeric urethanes and thermal dissociation of the latter, in which by-products formed are at least partly utilized.