Basf Se Corporation

Verein Für Kernverfahrenstechnik Und Analytik Rossendorf E.v.

Reiner Reetz

Holger Allardt

Renate Hempel

Michael Zoellinger

Ruediger Fritz

Andreas Raichle

Michael Reichelt

Johannes Buettner

Anne-Kathrin Merten

Stefanie Haase

Rüdiger Fritz

Johannes Büttner

Michael Zöllinger

Doris Zschieschang

Ina Homann

Annett Gersdorf

Elvira Flegel

Reinhard Tonder

The present invention relates to a process for workup of nitrite-comprising alkaline process wastewaters from the nitration of aromatic compounds, wherein the alkaline process wastewater is acidified by addition of acids and the offgas which comprises nitrogen oxides and escapes from the acidified process wastewater is worked up, comprising the steps of

[object Object]

Precipitations of nitrohydroxyaromatic salts out of the nitrated crude products obtained in the nitration of aromatic compounds after alkaline scrubbing, for example mononitrotoluenes, are prevented by contacting the nitrated crude products with an acidic ion exchanger. The nitrated crude products are preferably selected from a feedstream to a distillation column, a bottoms circulation stream of a distillation column and a feedstream to a vaporizer.

Prevention of precipitation from nitrated aromatic crude products

A process for working up alkaline process wastewater from the nitration of aromatic compounds to mono-, di- and trinitroaromatics, said alkaline process wastewater having a pH of 7.5 to 13, comprising the steps of

Acidic sludge adsorption of DNT wastewaters

The invention provides a process for removing nitrocresols from wastewater of mononitrotoluene preparation, which comprises acidifying the alkaline wastewater of mononitrotoluene preparation with acids to a pH of at most 3 and treating the nitrocresols with an extractant. The invention further provides the preparation of dinitrotoluene by use of the nitrocresol-containing extracts as a feedstock.

Method for extracting nitrocresols from waste water produced in the manufacture of mononitrotoluene and use of said extract

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Schwarzheide, Germany

Reiner Reetz