Process for the production of nitroaromatic compounds

US5696305A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Uwe Klingler · Dormagen, DE
• Thomas Schieb · Rösrath, DE
• Gerhard Wiechers · Leverkusen, DE
• Jurgen Zimmermann · Salzgitter, DE

Key dates

• Filing date: Aug 3, 1995
• Grant date: Dec 9, 1997
• Expiry date: Aug 3, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C201/08
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Nitroaromatic compounds are produced by continuously reacting an aromatic compound with nitrating acid. The reaction mixture is separated into an organic phase from which the desired nitroaromatic compound is recovered and an acid phase. The acid phase is subjected to flash evaporation to remove at least 5% by weight of the water present therein. The vapors generated during the flash evaporation are introduced into a jet spray of coolant to produce a condensate made up coolant, condensed vapors and suspended organic compounds. A portion of the condensate is subjected to phase separation to remove water and organic compounds present therein. The water and organic compounds may be reused. The process of the present invention is particularly advantageous in that deposits which block pipelines and interfere with heat transfer are not generated.