Process for preparing aniline

US7692042B2 · kind B2 · utility

Assignee

• Bayer MaterialScience AG · DE

Inventors

• Markus Dugal · Kempen, DE
• Franz-Ulrich Von Gehlen · Krefeld, DE
• Stefan Wershofen · Mönchengladbach, DE
• Andre Lago · Hamburg, DE
• Peter Lehner · Baytown, US
• Benie Marotz · Mülheim an der Ruhr, DE

Key dates

• Filing date: Feb 15, 2007
• Grant date: Apr 6, 2010
• Expiry date: Mar 5, 2027

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C263/10
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Crude aniline is produced by hydrogenating nitrobenzene in the presence of a catalyst. This crude aniline is then purified by means of a single-step or multi-step distillation process in which aqueous alkali metal hydroxide solution is added to the crude aniline prior to distillation and/or during distillation of the crude aniline.