Separation of a substance mixture consisting of hydrogen chloride and phosgene

US7584629B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Martin Sohn · Mannheim, DE
• Eckhard Stroefer · Mannheim, DE
• Filip Nevejans · Sint-Niklaas, BE
• Ulrich Penzel · Lauscha, DE
• Hans-Juergen Pallasch · Ludwigshafen, DE
• Peter Van Den Abeel · Brasschaat, BE
• Filip Deberdt · Bonheiden, BE
• Jan Jacobs · Hoogerheide, NL
• Wolfgang Mackenroth · Bad Dürkheim, DE

Key dates

• Filing date: Dec 13, 2003
• Grant date: Sep 8, 2009
• Expiry date: Mar 12, 2025

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/151
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The invention relates to a process for the partial or complete separation of a mixture comprising hydrogen chloride and phosgene, possibly solvents and possibly low boilers and inerts as are typically obtained in the preparation of isocyanates by reaction of amines with phosgene, which comprises firstly carrying out a partial or complete condensation of phosgene, then a distillation or stripping step in a column to remove the hydrogen chloride from the bottom product phosgene and subsequently a scrub of the top product hydrogen chloride by means of the process solvent to absorb the phosgene in the process solvent. An after-purification by means of adsorption on activated carbon or by another suitable method can subsequently be carried out to remove solvent residues.