Degussa Aktiengesellschaft

Evonik Degussa Gmbh

Thyssenkrupp Industrial Solutions Ag

E.i. Dupont De Nemours and Company

Degussa - Huls Ag

Uhde Gmbh

Evonik Operations Gmbh

Bernd Jaeger

Thomas Haas

Willi Hofen

Wolfgang Wöll

Guido Stochniol

Rudolf Vanheertum

Norbert Ullrich

Bärbel Kolbe

Marc Brendel

Norbert Finke

Werner Burkhardt

Christian Lettmann

David Bolz

Manfred Bärz

Niels Bredemeyer

Maik Bernhard

Juergen Grunert

Monika Berweiler

Wilhelm Keim

Hans-Jurgen Kohle

Johannes Kowoll

Daniel Ostgard

Matthias Pascaly

Holger Wiederhold

Hans-Jürgen Köhle

J&ouml;rg Sauer

Jürgen Glenneberg

Claudia Brasse

Joerg Sauer

Jorg Sauer

Michael Kleiber

Sebastian Imm

Peter Porscha

Klaus Stadtmueller

Robert Jahn

Marina Lazar

Hans-Christian Dietz

Jürgen Schemel

Joerg Lotz

Michael Dopfer

Georg Friedrich Thiele

Dana Pfenning

Jürgen Grunert

Robert Weber

Juergen Glenneberg

In a process for the epoxidation of propene, comprising the steps of reacting propene with hydrogen peroxide, separating propene oxide and a recovered propene stream from the reaction mixture, separating propane from all or a part of the recovered propene stream in a Csplitter column, and passing the overhead product stream of the Csplitter column to the epoxidation step, a propane starting material with a propane fraction of from 0.002 to 0.10 is used, the epoxidation is operated to provide a propane fraction in the reaction mixture of from 0.05 to 0.20 and the Csplitter column is operated to provide an overhead product stream which comprises a propane fraction of at least 0.04 in order to reduce the size and the energy consumption of the Csplitter column.

Process for the epoxidation of propene

During start-up of a continuous epoxidation of propene with hydrogen peroxide in a methanol solvent with a shaped titanium silicalite catalyst in a tube bundle reactor with a cooling jacket, cooling medium is fed at the rate for full load of the reactor with a constant entry temperature of from 20&#xb0; C. to 50&#xb0; C., methanol solvent is fed at a rate of from 50 to 100% for full load of the reactor, hydrogen peroxide is fed at a rate that starts with no more than 10% of the rate for full load and is increased continuously or stepwise to maintain a maximum temperature in the fixed bed of no more than 60&#xb0; C. and a difference between the maximum temperature in the fixed bed and the cooling medium entry temperature of no more than 20&#xb0; C., and propene is fed at a rate of from 20 to 100% of the rate for full load, increasing the feeding rate when the molar ratio of propene to hydrogen peroxide reaches the molar ratio for full load.

The process for preparing 1,2-propanediol from propene and hydrogen peroxide comprises the steps of

Method for producing propylene glycol from propene and hydrogen peroxide

Propene is continuously reacted with hydrogen peroxide in a tube bundle reactor comprising a multitude of parallel reaction tubes in the presence of a titanium silicalite catalyst arranged as a fixed bed in the reaction tubes. A cooling jacket encloses the reaction tubes, which has a feed point for cooling medium near the entry of the reaction tubes, a withdrawal point for cooling medium near the end of the reaction tubes and at least one additional withdrawal point upstream of the withdrawal point near the end of the reaction tubes. Cooling medium is fed to the feed point for cooling medium, a part of the cooling medium is withdrawn at the at least one additional withdrawal point and the remainder exits at the withdrawal point near the end of the reaction tubes.

Process and reactor for the epoxidation of propene

In a process for the epoxidation of propene, comprising the steps: reacting propene with hydrogen peroxide in the presence of a titanium silicalite catalyst and a methanol solvent; separating non-reacted propene and propene oxide from the resulting reaction mixture to provide a solvent mixture comprising methanol and water in a combined amount of at least 90% by weight; and feeding this solvent mixture as a feed stream to a continuously operated methanol distillation column at a feed point in the middle section of said column to provide an overhead product comprising at least 90% by weight methanol and a bottoms product comprising at least 90% by weight water; the addition of a liquid defoamer, having a solubility in the feed stream of less than 10 mg/kg at 25&#xb0; C. and a surface tension at the liquid air interface of less than 22 mN/m at 20&#xb0; C., at or above the feed point in an amount exceeding the solubility of the liquid defoamer in the feed stream suppresses foam formation in the methanol distillation column.

The invention relates to a process for hydrogenating an aromatic amine that has at least one amino group bound to an aromatic nucleus with hydrogen in the presence of a supported catalyst that contains at least ruthenium as active metal. The catalyst support has a BET surface area in the range from greater than 30 m/g to less than 70 m/g and more than 50% of the pore volume of the catalyst support is formed by macropores having a pore diameter of greater than 50 nm and less than 50% are mesopores having a pore diameter of 2 to 50 nm.

Process for hydrogenating an aromatic amine in the presence of a supported ruthenium catalyst

The invention relates to a process for the production of hydrogen peroxide by the anthraquinone process, comprising a hydrogenation stage, an oxidation stage and an extraction stage. According to the invention, catalytic hydrogenation of anthraquinone derivatives dissolved in a working solution is carried out in the presence of added molecular oxygen. Per mol hydrogen, 0.1 to 10 mmol oxygen is preferably introduced into the hydrogenation stage with the hydrogenating gas, in mixture with an inert gas and/or dissolved and/or dispersed in the working solution. This increases the residence time of the catalyst.

Process for the production of hydrogen peroxide

The invention relates to a process for increasing the selectivity of the hydrogenation of 4,4'-diaminodiphenylmethane (4,4&#x2032;-MDA) to diaminodicyclohexylmethane (4,4&#x2032;-HMDA) by catalytic hydrogenation of a mixture containing 4,4&#x2032;-MDA as the main component and its mono-N-methyl derivative as a secondary component. According to the invention, the hydrogenation is terminated before a conversion of 4,4&#x2032;-MDA to 4,4&#x2032;-HMDA of 99% is achieved. Under these conditions, a substantially smaller proportion of the N-methyl-4,4&#x2032;-MDA is hydrogenated to N-methyl-4,4-HMDA.

Process for increasing the selectivity of the hydrogenation of 4,4'-diaminodiphenylmethane to 4,4&#x2032;-diaminodicyclohexylmethane in the presence of an N-alkyl-4,4&#x2032;-diaminodiphenylmethane

A process for the continuous epoxidation of propene with hydrogen peroxide in the presence of a titanium silicalite catalyst and a methanol solvent, wherein the catalyst is periodically regenerated by washing with a methanol solvent at a temperature of at least 100&#xb0; C. and the epoxidation reaction is carried out for periods of more than 300 h between two regeneration steps.

Carrier-bound ruthenium catalysts are used to produce alcohols by the catalytic hydrogenation of aldehydes and ketones. The problem of deactivation of the catalyst is solved by the use of a ruthenium catalyst on an oxide carrier of the series TiO , SiO , ZrO , MgO, mixed oxides thereof and silicates thereof. In particular, Ru on TiO or SiO results in a long service life of the catalyst.

Method of producing alcohols by catalytic hydrogenation of aldehydes or ketones

Process for the preparation of isophorone diamine from isophorone nitrile, isophorone nitrilimine or mixtures containing isophorone nitrile and/or isophorone nitrilimine by hydrogenation through to amine in the presence of at least ammonia, hydrogen and a formed Raney hydrogenation catalyst based on cobalt, nickel, copper and/or iron, wherein the Raney catalyst is present in the form of hollow bodies.

Process for the preparation of 3-aminomethyl-3,5,5-trimethylcyclohexylamine

The present invention provides an improved process for the hydrogenation of 3-hydroxypropanal to 1,3-propanediol which comprises purifying an aqueous solution of 3-hydroxypropanal by contacting said aqueous solution with a purifying agent prior to hydrogenation.

Catalytic hydrogenation of 3-hydroxypropanal to 1,3-propanediol

A two-stage process for producing 1,3-propanediol by first hydrogenating at a temperature of 30&deg; C. to 80&deg; C. in the presence of an oxide-supported metal hydrogenation catalyst. Second, the resulting reaction solution is hydrogenated at a temperature of 80&deg; C. to 180&deg; C. to a 3-hydroxypropanal conversion of substantially 100% in the presence of an activated carbon-supported metal hydrogenation catalyst.

Two-stage process for the production of 1,3-propanediol by catalytic hydrogenation of 3-hydroxypropanal

&bgr;-Hydroxyaldehydes are produced by a method in which 1,2-oxiranes are reacted with carbon monoxide and hydrogen in the presence of transitional metal compounds which are modified with phosphorus-oxygen ligands or nitrogen-oxygen ligands and which act as a catalyst.

Method of producing &bgr;-hydroxyaldehydes

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Darmstadt, Germany

Bernd Jaeger