Basf Aktiengesellschaft

Basf Se Corporation

Basf Akiengesellschaft

Jörg Heilek

Bernd Eck

Dieter Baumann

Klaus Joachim Müller-Engel

Ulrich Hammon

Daniela Rieck

Martin Dieterle

Sylke Haremza

Klemens Massonne

Alexander Weck

Volker Schliephake

Thomas Krug

Harald Rust

Jürgen Schröder

Matthias Maase

Joachim Thiel

Armin Diefenbacher

Thomas Walter

Christoph Adami

Jordan Keith Lampert

Veit Stegmann

Jens Weiguny

Gunther Windecker

Alexander Hauk

Kirill Bramnik

Hermann Ascherl

Armin Schraut

Steffen Rissel

Thorsten Friese

Peter Zurowski

Oliver Huttenloch

Martin Fiene

Till Blum

Klaus Borho

Ellen Dahlhoff

Wolfgang Schneider

Stefan Gropp

Peter Schlemmer

Robert Lenz

Emile De Decker

Ulrich Jäger

Michael-Dieter Ulbrich

Frank Kuhnke

Wolfgang Gunkel

Gerhard Laux

Erik Bastiaensen

Wolf-Steffen Weiβker

Ralf Freyberger

Dirk Litters

Rainer Askani

Freidrich-Georg Martin

Gunter Schnabel

Imke Britta Müller

Wolf-Steffen Weißker

Gerhard Bertlein

Karl Heinz Schall

The present invention relates to a process comprising at least the steps (A) chemical reaction of at least one organic compound in the presence of at least one heterogeneous catalyst in a reaction mixture and (B) removal of the at least one heterogeneous catalyst by means of a magnetic filter, and also the use of a magnetic filter for separating off catalyst particles in a process for the hydrogenation of at least one organic compound.

Method of separating off magnetizable catalyst particles by means of magnetic filters

Processes for decreasing fumaric acid deposits in preparing maleic anhydride by heterogeneously catalyzed oxidation of a hydrocarbon with molecular oxygen. Maleic anhydride is absorbed from the crude mixture in an absorbent in an absorption column and desorbed in a desorption column, the entirety or portion of absorbent depleted in maleic anhydride, for controlled precipitation of fumaric acid, being cooled and/or concentrated by evaporating a portion of absorbent such that the difference between the concentration of fumaric acid in the recycle stream at the outlet of the desorption column under existing conditions and the equilibrium concentration of fumaric acid according to the solubility curve after cooling and/or evaporation of a portion of absorbent is &#x2267;250 ppm by weight, and the fumaric acid precipitated as a solid is removed completely or partly from the absorbent recycling system and the fumaric acid-depleted absorbent is recycled completely or partly to the absorption column.

Process for separating off fumaric acid and other minor components during the production of maleic anhydride

The invention relates to a process for purifying an ionic liquid, which comprises the steps (a) partial crystallization of the ionic liquid from its melt and (b) separation of the crystals from the residual melt.

Purification of ionic liquids

A process for continuously removing a target product X in the form of fine crystals from a liquid phase P comprising the target product X and constituents other than the target product X by cooling suspension crystallization in the secondary chamber, into which the liquid phase P flows continuously, of an indirect heat exchanger with simultaneous continuous flow of a coolant through the primary chamber of the indirect heat exchanger and continuous withdrawal of a crystal suspension S having a degree of crystallization Y from the secondary chamber, in which the degree of crystallization Y is adjusted on the basis of a heat balance conducted continuously with the aid of a process computer.

Process for continuously removing a target product X in the form of fine crystals

A process for removing methacrylic acid from liquid phase P comprising acrylic acid as a main constituent and target product, and methacrylic acid as a secondary component in which the removal is effected by crystallization, the acrylic acid accumulating in the crystals formed and the methacrylic acid in the remaining mother liquor.

Process for removing methacrylic acid from liquid phase comprising acrylic acid as a main constituent and target product, and methacrylic acid as a secondary component

The calculation of the above balance shows that the division of stream () into the streams () and () used here leads to the fact that in the neutralization stage no excess sodium formate is produced, so that any ejection can be omitted. Furthermore, the water content of the stream () comprising sodium formate recirculated to the first crystallization stage in this case can be set to a very low value.

Production of sodium diformate

The present invention relates to the use of an optical line detector for regulating the position of the wash front and/or of the build-up front of the crystal bed of a wash column in a melt crystallization process and a corresponding regulation method. The line detector, for example a CCD camera or a linear array of reflection probes, is arranged in such a way that optical properties of the crystal bed can be detected continuously in a region running parallel to the longitudinal axis of the wash column, this region covering the desired setpoint position of the wash front or of the build-up front.

Regulation of a wash column in a melt crystallization process

In a process for the purification of a crude acrylic acid melt, the crude acrylic acid melt is converted, under the action of low temperatures, into a crude acrylic acid suspension consisting of acrylic acid crystals and residual melt, and the acrylic acid crystals of the crude acrylic acid suspension are freed from remaining residual melt in a wash column, the production of the acrylic acid crystals of the crude acrylic acid suspension being carried out in the presence of water, the wash column being a wash column with forced transport of the acrylic acid crystals and the wash liquid used being the melt of acrylic acid crystals purified in the wash column.

Method for the purification of a crude acrylic acid melt

In a process for preparing acrylic acid, an acrylic acid-containing product gas mixture obtained by catalytic gas phase partial oxidation of a Cprecursor of acrylic acid, after direct cooling with a quench liquid, is fractionally condensed in a separating column provided with internals, rising into itself with sidestream takeoff of crude acrylic acid, and the acrylic acid oligomers which form are dissociated and the resulting dissociation gas is subjected to a countercurrent rectification before it is recycled.

Preparation of acrylic acid

Acrylic acid or methacrylic acid is purified by crystallization to obtain crystals and a mother liquor, by a process in which the crystals are washed with a wash liquid containing the acid and having a temperature from 15 to 40&#xb0; C. Furthermore, a process for the preparation of acrylic acid or methacrylic acid comprises the abovementioned purification process.

Process for the purification and preparation of acrylic acid or methacrylic acid

(Meth)acrylic acid is purified by crystallization by a process in which the (meth)acrylic acid is purified by a combination of at least two different dynamic crystallization processes, in particular a suspension crystallization and a layer crystallization.

Purification method for (meth)acrylic acid

The invention is directed toward preparation of (meth)acrylic acid, comprising condensation of a gas comprising (meth)acrylic acid, absorption with water, and extraction with an aqueous solution forming a miscibility gap.

Preparation of (meth)acrylic acid

In a process for crystallizing material to be isolated, fluid is vaporized from a melt or a solution comprising the material to be isolated and the fluid and the vaporized fluid is condensed or absorbed in a liquid material to form a liquid mixture, wherein the fluid components to be condensed/absorbed have partial pressures over the liquid mixture which are smaller than the partial pressures of these components over the crystallizing solution/melt and the freezing point of the liquid mixture is lower than the condensation/absorption temperature in the liquid mixture.

Crystallization by evaporation and vapor condensation

A process for separating a liquid eutectic mixture by crystallization of one eutectic forming substance of the mixture on a cold surface to which seed crystals of the eutectic forming substance have been applied in the form of a seed crystal layer, and subsequent removal of the eutectic forming substance in liquid form after heating of the surface.

Separation of liquid eutectic mixtures by crystallization on cold

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Bammental, Germany

Jörg Heilek