Method for producing isocyanates

US10858310B1 · kind B1 · utility

Assignee

• Covestro Deutschland AG · DE

Inventors

• Daniela Cozzula · Bad Kreuznach, DE
• Andreas Ernst · Worms, DE
• Matthias Leven · Cologne, DE
• Walter Leitner · Aachen, DE
• Thomas Mueller · Leonberg, DE
• Christoph Guertler · Cologne, DE
• Stefan Wershofen · Mönchengladbach, DE
• Gernot Jaeger · Cologne, DE
• Franz Beggel · Cologne, DE
• Jens Langanke · Mechernich, DE

Key dates

• Filing date: Aug 31, 2018
• Grant date: Dec 8, 2020
• Expiry date: Aug 31, 2038

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J2531/002
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The invention relates to a method for producing an isocyanate, wherein a carbamate or thiolcarbomate is converted, in the presence of a catalyst, with separation of an alcohol or thioalcohol, at a temperature of at least 150° C., to the corresponding isocyanate, wherein a compound of the general formula (X)(Y)(Z—H) is used as a catalyst, in particular characterized in that the compound has both a proton donor function and a proton acceptor function. In the catalysts according to the invention, a separable proton is bound to a heteroatom, which is more electronegative than carbon. Said heteroatom is either identical to Z or a component thereof. In the catalysts according to the invention, there is additionally a proton acceptor function which is either identical to X or a component thereof. According to the invention, the proton donator and proton acceptor function are connected to each other by the bridge Y.