Process for separating solid 1,5- and/or 1,8-dinitroanthraquinone and liquid nitrobenzene

US4389344A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Axel Schaefer · Hattersheim, DE
• Werner Motika · Marne, DE
• Wolfgang Bender · Wuppertal, DE
• Jorn Todt · Leverkusen, DE
• Udo Oels · Krefeld, DE

Key dates

• Filing date: Nov 29, 1979
• Grant date: Jun 21, 1983
• Expiry date: Nov 29, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C2603/24
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process and an equipment for obtaining dry 1,5- and/or 1,8-dinitroanthraquinone from suspensions which contain liquid nitrobenzene whereby in a first stage solid 1,5- and/or 1,8-dinitroanthraquinone with a content of less than 30% by weight of nitrobenzene is separated off mechanically from the suspension at elevated temperature and whereby in a second stage the residued nitrobenzene is removed from the separated 1,5- and/or 1,8-dinitroanthraquinone by lowering the pressure during which the temperature falls.