Basf Aktiengesellschaft

Basf Se Corporation

Josef Meissner Gmbh & Co. Kg

Renate Hempel

Udo Rotermund

Holger Seifert

Holger Allardt

Werner Wiegmann

Ruediger Fritz

Sebastian Ahrens

Samuel Neto

Manfred Genz

Ruediger Krech

Julia Leschinski

Barbara Becker

Heinz Bollmann

Michael Zoellinger

Wolfgang Scholz

Gottfried Knorr

Marion Heinz

Reiner Reetz

Yuan Shen Dai

Mirko Haendel

Peter Falke

Heinrich Hermann

Armin Lange De Oliveira

Michael Reichelt

Mirko Händel

Anja Biedermann

Jürgen Pöhlmann

Anne-Kathrin Merten

Barbara Wucher

Werner Schmiade

Peter Von Malotki

Christian Bechtold

Katharina Spuhl

Rüdiger Fritz

Michael Friko

Yuanshen Dai

Juergen Poehlmann

Michael Zöllinger

Doris Zschieschang

Ina Homann

Henrich Hermann

Annett Gersdorf

Elvira Flegel

The present invention relates to a process for continuous hydrogenation of a nitro compound to the corresponding amine in a liquid reaction mixture comprising the nitro compound in the presence of a supported catalyst which comprises as the active component at least one element from groups 7 to 12 of the periodic table of the elements, wherein the hydrogenation is performed in the presence of at least one salt selected from the group consisting of the salts of the alkali metals, alkaline earth metals and of the rare earth metals and to a supported catalyst for continuous hydrogenation of a nitro compound to the corresponding amine in a liquid reaction mixture comprising the nitro compound which comprises as the active component at least one element from groups 7 to 12 of the periodic table of the elements and one salt of the alkali metals, alkaline earth metals or of the rare earth metals.

Catalyst modification with alkali metal, alkaline earth metal or rare earth metal ions in the continuous liquid-phase hydrogenation of nitro compounds

Process for scrubbing a crude mixture which is obtained in the nitration of toluene after separating off the nitrating acid and comprises dinitrotoluene, nitric acid, nitrogen oxides and sulfuric acid, which comprises two scrubbing steps (WS-I) and (WS-II), wherein i) in a first scrubbing step (WS-I), the crude mixture is extracted with a scrubbing acid I comprising nitric acid, nitrogen oxides and sulfuric acid in a scrub comprising at least one extraction stage, where the scrubbing acid discharged from the first extraction stage (WS-I-1) of the first scrubbing step (WS-I) has a total acid content of from 10 to 40% by weight and a content of from 80 to 350 ppm of hydrocyanic acid, giving a prescrubbed crude mixture, ii) in a second scrubbing step (WS-II), the prescrubbed crude mixture comprising dinitrotoluene is extracted with a scrubbing acid II in a scrub comprising at least one, preferably at least 2, extraction stage(s), where the scrubbing acid discharged from the first extraction stage (WS-II-1) of the second scrubbing step (WS-II) has a pH of less than or equal to 4, giving a dinitrotoluene-comprising mixture which is essentially free of nitric acid, sulfuric acid, nitrogen oxides and hydrocyanic acid and has a content of not more than 300 ppm of nitric acid and nitrogen oxides, not more than 3 ppm of sulfate and not more than 50 ppm of hydrocyanic acid.

Process for acidic scrubbing of dinitrotoluene in the presence of hydrocyanic acid

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

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A process for the preparation of dintrotoluene which comprises (a) nitrating toluene with a nitrating acid, wherein said nitrating acid is a mixture of nitric acid and sulfuric acid, in one or more nitration steps, and separating the nitrating acid from the process stream thus formed, wherein a crude mixture comprising dinitrotoluene and a fraction of said nitrating acid dissolved therein is obtained, said crude mixture further comprising at least 50 ppm of HCN, and (b) washing the crude dinitrotoluene containing mixture in one or more washing steps, wherein, before the first washing step is carried out, the crude mixture is distilled and/or stripped to remove HCN therefrom, wherein a crude dinitrotoluene containing mixture which is essentially free of HCN is obtained.

Method for removing HCN from crude dinitro toluene

The invention relates to a process for scrubbing a crude mixture comprising dinitrotoluene, nitric acid, nitrogen oxides and sulfuric acid obtained in the nitration of toluene after the nitrating acid has been separated off, which comprises two scrubbing steps (SS-I) and (SS-II), wherein

Process for scrubbing dinitrotoluene

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

Prepolymers which contain isocyanate groups, have an NCO content of at least 30.0% by weight and can be prepared by reacting an isocyanate mixture consisting predominantly of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates and having a proportion of two-ring isomers of not more than 74% by weight with at least 4-functional polyols or a mixture of polyols having a mean functionality of at least 4, where the polyols or polyol mixtures have a hydroxyl number of from 200 to 1650 mg KOH/g and a number average molecular weight of less than 1100 g/mol. The present invention also provides a process for preparing these prepolymers containing isocyanate groups, provides for their use for producing polyurethanes and provides a process for producing polyurethanes by reacting at least one novel prepolymer containing isocyanate groups, if desired in admixture with further organic and/or modified organic isocyanates (a), with compounds having at least two reactive hydrogen atoms (b) in the presence of, if desired, blowing agents (c), catalysts (d) and, if desired, further auxiliaries and/or additives (e).

Prepolymers containing isocyanate groups and a method for the production thereof

Thermally stable rigid foams based on isocyanate and having low brittleness and low thermal conductivity

Storage-stable, blowing agent-containing emulsions for producing rigid foams based on isocyanate

Microcellular urea-containing polyurethane elastomer

Microcellular polyurethane elastomer containing urea groups

Blowing agent-containing emulsions comprise

Storage-stable emulsions for producing fine-celled rigid foams based on

In a process for producing rigid polyurethane foams having improved heat distortion resistance and reduced thermal conductivity by reacting

Production of rigid polyurethane foams

In a process for producing rigid foams based on isocyanate, the blowing agent used is a mixture of at least one low-boiling hydrocarbon having from 3 to 7 carbon atoms, low molecular weight monohydric alcohols containing primary or secondary hydroxyl groups and having from 1 to 4 carbon atoms, and, if desired, the carbon dioxide formed from water and isocyanate. The rigid foams can be used as insulation material.

Production of rigid foams based on isocyanate

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Ruhland, Germany

Renate Hempel