Bayer Aktiengesellschaft

Lanxess Deutschland Gmbh

Saltigo Gmbh

Symyx Technologies, Inc.

Ulrich Notheis

Hans-Josef Buysch

Paul Wagner

Hans-Dieter Gerriets

Michael Friederich

Pieter Ooms

Johann Rechner

Reinhard Langer

Gerhard Darsow

Carsten Hesse

Christine Mendoza-Frohn

Christian Laue

Rudolf J Klee

Ralph Armbrust

Alexander Klausener

Alfred Gerhard Hagemeyer

David M Lowe

Heinrich Konigshofen

Christian Rasp

Lars Rodefeld

Wolfgang Mägerlein

Gunter Rauchschwalbe

Ursula Pentling

Xiao Ping Zhou

Christiane Oppenheimer-Stix

Damodara M Poojary

Dirk Müller

Marielouise Schneider

Nikolaus Müller

Jurgen Scharschmidt

Heinrich Grzinia

Anke Beckmann

Ramesh Borade

Brian Schwegler

Carsten Hummelt

Alexander Wagner

Hans-Detlef Heinz

Mathias Siekmann

Uwe Boger

Heinrich Grizinia

J Urgen Scharschmidt

The present invention relates to a method for producing trimethylolpropane having a low color number by processing a raw reaction solution obtained according to the inorganic Cannizarro process while adhering to precisely defined pH values.

Method for improving the color number of trimethylolpropane

The present invention relates to a method for isolating ditrimethylol propane from secondary trimethylol propane production streams.

Method for isolating di-trimethylol propane

The present invention relates to the industrial production of vinylene carbonate (VC) by elimination of hydrogen chloride from chloroethylene glycol carbonate (CGC) with tertiary amines in the absence of relatively large amounts of additional solvent.

Process for producing vinylene carbonate

The present invention relates to a method for the production of trimethylolpropane with a low color number by treatment with activated carbon.

The present invention relates to a process for preparing monomethylhydrazine by methylating hydrazine or hydrazinium hydrochloride or hydrazinium dihydrochloride with methyl chloride and/or a methano/HCl mixture, characterized in that the reaction mixture formed in the methylation is reacted with an organic base from the group of the alkylamines or alkanolamines and monomethylhydrazine is removed by distillation from the reaction mixture in a low boiler fraction and the low boiler fraction is optionally subjected to a further distillation.

Process for preparing monomethylhydrazine

The present invention relates to a process for preparing trimethylolpropane having a low APHA color number.

Preparation of trimethylolpropane

Noble metal/reducible metal oxide catalysts effective for the direct amination of aromatic hydrocarbons and heterocyclic analogs thereof are disclosed. In one embodiment, the cataloxidant comprises a noble metal selected from Pd, Rh, Ir and/or Ru and a reducible metal oxide. In another embodiment, the cataloxidant comprises a noble metal and a reducible oxide of a metal selected from Ni, Mn, V, Ce, Th, Pr, Te, Re, Co, Fe, Cu and/or Bi. A preferred cataloxidant comprises one or more noble metals selected from Pd, Rh, Ir and/or Ru, in combination with nickel oxide and/or manganese oxide. In preferred applications, benzene can be aminated in the presence of the cataloxidants to form aniline. A benzene conversion of at least 5% is achieved, with more than 90% selectivity for aniline. Significantly, the cataloxidant can be regenerated without a substantial loss of performance.

Amination of aromatic hydrocarbons and heterocyclic analogs thereof

Described is a process for preparing an aromatic carbonate, e.g., diphenyhl carbonate, in which an aromatic hydroxy compound, e.g., phenol, is reacted with carbon monoxide and oxygen in the resence of a supported catalst prepared by a sol-gel process, a quatermary ammonium or phosphonium salt and a base. The sol-gel supported catlyst comprises: (i) a first metal oxide selected from the group consisting of silicon oxide, aluminum oxide, titanium oxide, zirconium oxide and mixtures thereof; (ii) a second metal oxide selected from the group consisting of oxides of the elements of groups 4, 5, 6, 7, 11, 12, 13, 14, the iron group (atomic numbers 26 to 28), the rare-earth metals (atomic numbers 58 to 71) and mixtures thereof; and (iii) a metal selected from the group consisting of platinum metals, compounds of platinum metals (atomic numbers 44 to 46 and 77 and 78) and mixtures thereof. The sol-gel supported catlyst is aged, dried and optionally annealed prior to use in the process of the present invention.

Catalysts containing a platinum group metal and produced in a sol-gel method, as well as a method for producing diarylcarbonates

A platinum metal-containing supported catalyst in which the support contains mixed oxides of metals, transition metals and semiconductor elements, which can act as redox catalysts under the reaction conditions is disclosed. Also disclosed is the preparation of these catalysts and their use in a process for preparing diaryl carbonates.

Supported catalysts containing a platinum group metal and method for producing diarylcarbonates

4-aminodiphenylamines are prepared by hydrogenating nitrosobenzene or mixtures of nitrosobenzene and nitrobenzene with hydrogen in the presence of bases containing hydroxide, oxide and/or alkoxide groups and heterogeneous catalysts in inert aprotic solvents at temperatures of from 0 to 200.degree. C. and at pressures of from 0.1 to 150 bar.

Process for the preparation of 4-aminodiphenylamine

4-aminodiphenylamines are produced by hydrogenating nitrobenzene with hydrogen in the presence of bases containing hydroxide and/or oxide groups and heterogeneous catalysts and in the presence of inert aprotic solvents at temperatures of 0 to 200.degree. C. and pressures of 0.1 to 150 bars.

Process for producing 4-aminodiphenylamine

Carbazole can be prepared by dehydrogenation of compounds of the formula ##STR1## or by aminating dehydrogenation of compounds of the formula ##STR2## at 300.degree. to 600.degree. C. in the presence of hydrogen over an iridium catalyst or an iridium-containing catalyst.

Process for the preparation of carbazole

A description is given of the preparation of hydroxybiphenyl by dehydrogenation of completely or partially hydrogenated precursors using a supported Rh catalyst which additionally contains chromium, manganese and alkali metal and can contain a sulphur compound. The Rh catalyst which can be used according to the invention is prepared from halide-free starting materials. The Rh catalyst is distinguished by a low dependence of the initial selectivity, with the selectivity in the run-in state and the running-in time on the conditions of the reductive pretreatment and requires only short running-in times to reach the optimum state.

Process for preparing hydroxybiphenyl

The preparation of optionally substituted diphenylamine by reaction of optionally substituted aniline with optionally substituted cyclohexanone using a supported Rh catalyst containing rhodium or a combination of rhodium with another platinum metal from the group of palladium, platinum, ruthenium or iridium and which can additionally contain chromium, manganese, alkali metal and a sulphur compound is described. The catalyst of the invention is prepared from halide-free starting materials. The Rh catalyst is distinguished by a low dependence of the initial selectivity, the selectivity in the run-in state and the running-in time on the conditions of the reductive pretreatment and requires only short running-in times to the optimum state.

Process for preparing diphenylamines and catalysts usable for this

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Dormagen, Germany

Ulrich Notheis