Evonik Rohm Gmbh

Evonik Roehm Gmbh

Gerhard Koelbl

Joachim Knebel

Guido Protzmann

Thomas Kehr

Steffen Krill

Torsten Balduf

Rudolf Burghardt

Thorben Schuetz

Harald Trauthwein

Guenther Lauster

Martin Koestner

Guenter Westhaeuser

Wolfgang Klesse

Bardo Schmitt

Ralf Meier

Dirk Broell

Benedikt Laux

Horst Hiltner

Eduard Rundal

Lorenza Sartorelli

Martina Ebert

Zhengfeng Zhang

Frederik Gluth

Huisheng Wang

Reed Zhao

Mirko Michel

Hans-Gerhard Stadler

The present invention relates to an optimized process for the preparation of methacrolein. Methacrolein is used in chemical synthesis particularly as an intermediate for the preparation of methacrylic acid, methyl methacrylate or even active ingredients, fragrances or flavorings. In particular the present invention relates to the optimization of the process parameters by which, inter alia, a reduction of the content of harmful dimeric methacrolein in the end product may be achieved.

Optimized method for producing methacrolein

The present invention relates to the oxidative combustion of amine-containing wastewaters, especially in a process for preparing methacrolein. Methacrolein is used in chemical synthesis particularly as an intermediate for preparation of methacrylic acid, methyl methacrylate, or else of active ingredients, odorants or flavorings. More particularly, the present invention relates to an oxidative combustion of the amine-containing wastewaters with only low nitrogen oxide formation.

Recirculation and disposal of aqueous catalyst solutions in amine catalytic processes

The present invention concerns regulating the water content in a process for production of methacrolein. Methacrolein is used in chemical synthesis particularly as an intermediate for production of methacrylic acid, methyl methacrylate or else of active, aroma or flavor chemicals. The present invention is particularly concerned with regulating the water content in a process for production of methacrolein from formaldehyde and propionaldehyde via a Mannich condensation.

Method of regulating the water content in a continuous method for producing methacrolein

This invention relates to a process of preparing highly pure, non-yellowing (meth)acrylic acid necessary for high-tech applications requiring long-tem color stability in the presence of amines. Process for the preparation of highly pure, non-yellowing (meth)acrylic acid comprising the steps: f) Condensation of a (meth)acrylic acid-containing gas phase obtained via a gas phase oxidation process of a C4-compound to generate an aqueous (meth)acrylic acid solution g) Separation of the (meth)acrylic acid from the aqueous (meth)acrylic acid solution to obtain crude (meth)acrylic acid h) Rectification of the crude (meth)acrylic acid to obtain pure (meth)acrylic acid via a sidestream outlet of the rectification column i) Treatment of the pure (meth)acrylic acid generated in step c) with an ion exchange resin j) Distillation of the (meth)acrylic acid generated in step d).

Process for preparation of highly pure, non-yellowing methacrylic acid

The present invention relates to a process for preparing ethylene glycol dimethacrylate, which comprises transesterification of ethylene glycol with an ester of methacrylic acid in the presence of catalysts, wherein a combination comprising lithium amide (LiNH) and lithium chloride (LiCl) is used as catalyst. The process of the invention makes it possible to prepare ethylene glycol dimethacrylate particularly inexpensively and in a very high purity.

Method for producing ethylene glycol dimethacrylate

The invention relates to a process for continuously preparing N-alkyl(meth)acrylamides by reacting alkyl(meth)acrylates with high-boiling amines. A catalyst activation and specific workup technique achieve product qualities which have not been achieved to date. In addition, very high space-time yields and overall yields can be achieved.

Method for continuously producing alkylamino(meth)acrylamides

The present invention relates to a process for preparation of pure methacrylic acid, at least comprising the process steps: a) gas phase oxidation of a C4 compound to obtain a methacrylic acid-comprising gas phase, b) condensation of the methacrylic acid-comprising gas phase to obtain an aqueous methacrylic acid solution, c) separation of at least a part of the methacrylic acid from the aqueous methacrylic acid solution to obtain at least one crude methacrylic acid-comprising product; d) separation of at least a part of the methacrylic acid from the at least one crude methacrylic acid-comprising product by means of a thermal separation process to obtain a pure methacrylic acid.

Process for preparation of high purity methacrylic acid

The present invention relates to a process for preparing (meth)acrylates, which comprises the transesterification of an alcohol with a low-boiling ester of (meth)acrylic acid in the presence of catalysts, with the alcohol liberated from the low-boiling ester of (meth)acrylic acid being separated off by distillation, characterized in that the molar ratio of low-boiling ester of (meth)acrylic acid to starting alcohol present in the reaction mixture is increased during the reaction by addition of low-boiling ester of (meth)acrylic acid. The process of the invention makes a particularly inexpensive preparation of (meth)acrylates having a very high purity possible.

Method for producing (meth)acrylates

The present invention relates to a process for preparing butanediol dimethacrylates, which comprises the transesterification of butanediol with an ester of methacrylic acid in the presence of catalysts, wherein a combination comprising at least one lithium compound and at least one calcium compound is used as catalyst, at least one of the compounds of lithium and/or of calcium is an oxide, a hydroxide, an alkoxide having from 1 to 4 carbon atoms or a carboxylate having from 1 to 4 carbon atoms and at least part of the reaction is carried out in the presence of an effective amount of water. The process of the invention makes a particularly inexpensive preparation of butanediol dimethacrylates having a very high purity possible.

Method for producing butanediol dimethacrylates

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Gernsheim, Germany

Gerhard Koelbl