Process for the selective absorption of chlorine and/or bromine from CO.sub. -containing off-gases with the aid of steam

US5124135A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Ulrich Girrbach · Frankfurt am Main, DE
• Edgar Hartl · Langen, DE
• Egon Malow · Hochheim, DE

Key dates

• Filing date: Oct 28, 1991
• Grant date: Jun 23, 1992
• Expiry date: Oct 28, 2011

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P70/10
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The invention provides a process for the selective absorption of chlorine and/or bromine from CO.sub.2 -containing off-gases. The off-gas must contain at least 1 mol of SO.sub.2 per mol of Cl.sub.2 and/or per mol of Br.sub.2 ; if necessary sufficient SO.sub.2 is added to the off-gas to give the above-mentioned relative amount. Chlorine and/or bromine is absorbed by mixing the off-gas with steam and then cooling the mixture until the steam condenses. An example of a suitable apparatus is a vertical tube having an internal cooling coil.