Energy-efficient method for providing a purified phosgene vapor

US10843927B2 · kind B2 · utility

Assignee

• Covestro Deutschland AG · DE

Inventors

• Michael Merkel · Hof, DE
• Martin Ehrig · Leverkusen, DE
• Manfred Kobylka · Burscheid, DE
• Jan Morbach · Cologne, DE
• Maria Carrascosa Mas · Cologne, DE
• Christian Jens · Cologne, DE

Key dates

• Filing date: Jun 22, 2018
• Grant date: Nov 24, 2020
• Expiry date: Jun 22, 2038

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J2219/00162
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The present invention relates to a method for producing purified phosgene vapor, comprising the following steps: 1) providing a gas flow obtainable from the reaction of chlorine with carbon monoxide and comprising phosgene and carbon monoxide; 2) one-stage or multi-stage condensation of the gas flow and separation of non-condensable residue gases; 3) one-stage or multi-stage evaporation of the liquid phosgene obtained in step 2) and optional overheating of the produced phosgene vapour, wherein there is an energy integration between one or more of the condensation steps of step 2) and one or more of the evaporation steps in step 3) and the pressure in the last condensation step is between ≥0.2 and ≤6.0 bar higher than in the first evaporation step.