Basf Aktiengesellschaft

Basf Se Corporation

The Dow Chemical Company

Armin Diefenbacher

Klaus Joachim Mueller-Engel

Martin Dieterle

Hartwig Voss

Ulrich Hammon

Stefan Bitterlich

Christoph Adami

Ingolf Voigt

Manfred Noack

Volker Schliephake

Claus Hechler

Jürgen Caro

Ronald Schäfer

Helmut Reichelt

Eckhard Stroefer

Otto Machhammer

Jochen Petzoldt

Georg Sieder

Klaus Joachim Müller-Engel

Hartwig Voβ

Frieder Borgmeier

Goetz-Peter Schindler

Götz-Peter Schindler

Gunter Schuch

Hannes Richter

Hans-Georg Goebbel

Sven Crone

Joerg Heilek

Tilman Sirch

Thomas Walter

Gerd-Dieter Tebben

Martin Sesing

Jörg Heilek

Alfred Krause

Anna Forlin

Ingo Klopp

Catharina Klanner

Martin Karches

Reinhard Schneider

Lothar Seidemann

Olga Schubert

Gunter-Rudolf Schroeder

Renate Patrascu

Thomas Grassler

Wolfgang Schneider

Henning Schultz

Michael Blechschmitt

Bernd Gerber

Juergen Decker

Franz Borgel

Gunter-Rudolf Schröder

Ludwig E Heck

Jürgen Decker

Juergen Caro

Bruno Seider

Hans-Georg Göbbel

The present invention relates to a process for preparing acrylic acid by two-stage heterogeneously catalyzed partial gas phase oxidation of propylene, in which the propylene source used is a preceding propane dehydrogenation and in which the first oxidation stage is operated with restricted propylene conversion, and unconverted propane and propylene present in the product gas mixture of the second partial oxidation stage are recycled substantially into the preceding propane dehydrogenation.

Preparation of acrylic acid by heterogeneously catalyzed partial gas phase oxidation of propylene

A process for heterogeneously catalyzed partial direct oxidation of propane and/or isobutane, in which target product is removed in a workup stage from the product gas mixture obtained in the reaction stage, the remaining residual product gas mixture is divided into two portions of the same composition, one portion is recycled into the reaction stage and the other portion is discharged, and both the reaction stage and the workup stage are operated at elevated pressure.

Heterogeneously catalyzed partial direct oxidation of propane and/or isobutane

A method for producing membranes which contain at least one solid layer on one side of a porous substrate by treating the side of the support, which is to be coated, with a synthetic solution that forms the solid layer. The inventive method is characterized in that the space located behind the side of the porous support, which is not to be coated, is filled with an inert fluid during the production of the solid layer on the porous support, 'behind' being from the perspective of the support. The pressure and/or the temperature of the fluid is/are selected such that the synthetic solution is essentially prevented from entering in contact with the side of the porous support, which is not to be coated.

Membrane production method

A process for the production of a composite membrane, one or more microporous separation layers comprising a zeolite of the MFI type being produced by hydrothermal synthesis on a porous substrate, wherein one or more additives from the group consisting of linear (C-C)-alcohols, ammonia, primary, secondary and tertiary amines having in each case (C-C)-alkyl radicals, (C-C)-aminoalcohols and (C-C)-ketones are added to the synthesis solution for the hydrothermal synthesis.

Process for producing a composite membrane

The present invention relates to a process for separating at least one propylene glycol from a mixture (M) comprising water and said propylene glycol, said process comprising (I) evaporating the mixture in at least two evaporation and/or distillation stages at decreasing operating pressures of the evaporators and/or distillation columns obtaining mixture (M') and mixture (M&#x2033;); (II) separating the mixture (M&#x2032;) obtained in (I) in at least one further distillation step, obtaining a mixture (M-I) comprising at least 70 wt.-% of water and a mixture (M-II) comprising less than 30 wt.-% of water.

Process for separating propylene glycol from aqueous compositions

A catalytic process for preparing chlorine from hydrogen chloride, which includes recycle of process streams with reduced accumulation of inert gases in the system is provided. The process includes a step wherein a compressed liquid stream comprising chlorine, carbon dioxide and oxygen is recycled into a column countercurrent to the ascending gas phase and feeding part of the chlorine-rich liquid phase leaving the bottom of the column back into the top of the column. Carbon dioxide present in the ascending gas stream is dissolved out of the gas stream and can later be separated from chlorine without problems by distillation.

Method for producing chlorine

The invention relates to a process for the preparation of sodium dithionite, comprising the steps

Method for producing sodium dithionite

A process for producing a liquid formulation of salts of sulfonated azo dyes by coupling an at least equimolar amount of diazotized aminoarylsulfonic acids IHN&#x2014;Ar&#x2014;SOH&#x2003;&#x2003;(I),where Ar is phenylene (which may be monosubstituted by sulfo) or naphthylene (which may be mono- or disubstituted by sulfo and/or monosubstituted by hydroxyl) onto the coupling product of an unsubstituted or methyl-substituted phenylenediamine with itself comprises dissolving the azo dye in a basic medium and then subjecting the solution to a nanofiltration.

Method for producing a liquid formulation of salts of sulphonic-acid azo dyes

A process for heterogeneously catalyzed partial gas phase oxidation of propylene to acrylic acid in the absence of propane as an inert diluent gas, in which, in the starting reaction gas mixture, cyclopropane is substantially avoided as an impurity and crude propylene is used additionally as a propylene source.

Process for heterogeneously catalyzed partial gas phase oxidation of propylene to acrylic acid

Composite membranes comprising at least one porous substrate layer and at least one microporous separation layer, comprising at least one zeolite of the MFI type, are described, the separation layer being produced by a hydrothermal synthesis in which the molar ratio of silicon to aluminum is greater than 120 and the separation layer contains less than 10% by weight of aluminum in elemental or chemically bound form in a zone of at least 100 nm adjacent to the separation layer.

Composite membrane

A process for preparing at least one target product by partial oxidation and/or ammoxidation of propylene, in which the propylene source used is a propane dehydrogenation, the propane used therein being obtained by a rectificative prepurification of crude propane.

Process for preparing at least one target product by partial oxidation and/or ammoxidation of propylene

A process for preparing acrolein or acrylic acid or a mixture thereof by heterogeneously catalyzed partial gas oxidation of propylene, in which the starting reaction gas mixture has the following contents:

Preparation of acrolein or acrylic acid or a mixture thereof by heterogeneously catalyzed partial gas phase oxidation of propylene

A process for separating acrylic acid and benzoic acid present in the product gas mixture of a partial oxidation to acrylic acid, in which the acrylic acid and the benzoic acid are first converted to a liquid phase, constituents having a lower boiling point than benzoic acid and acrylic acid are removed therefrom by thermal separating processes, and the acrylic acid is removed by crystallization from the remaining liquid phase.

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A process for preparing acrylic acid, in which an acrylic acid-comprising product gas mixture obtained by catalytic gas phase partial oxidation of a Cprecursor of acrylic acid is fractionally condensed in a condensation column provided with internals ascending into itself with side draw removal of crude acrylic acid and with liquid phase draw removal of acrylic acid-comprising acid water, and acrylic acid present in acid water is taken up into an extractant and then removed from the extractant and recycled into the condensation column, or taken up in aqueous metal hydroxide, or sent to further purification of the crude acrylic acid.

Process for preparing acrylic acid

Tray column and method for mass transfer in a tray column

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Germersheim, Germany

Armin Diefenbacher