Method for cleaning off-gas flows

US6696603B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Heinz Auer · Neulußheim, DE
• Bernd Bessling · Grünstadt, DE
• Hans Hammer · Mannheim, DE
• Hans Hasse · Kaiserslautern, DE
• Friedrich Sauer · Grünstadt, DE
• Maximilian Vicari · Schifferstadt, DE
• Gerhard Wagner · Brookline, US
• Till Adrian · Frankenthal (Pfalz), DE

Key dates

• Filing date: Jul 18, 2002
• Grant date: Feb 24, 2004
• Expiry date: Jul 18, 2022

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J2219/00006
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for the preparation of anhydrous or substantially anhydrous formic acid. The process has the special feature that a liquid of the general formula I where the radicals R1 and R2 are alkyl, cycloalkyl, aryl or aralkyl groups, or R1 and R2 jointly, together with the N atom, form a heterocyclic 5- or 6-membered ring, and only one of the radicals is an aryl group, and where R3 is hydrogen or a C1-C4-alkyl group, employed as extractant is also employed as washing liquid for the offgases produced in the process.