Patents by Inventor Udo Birkenstock
Udo Birkenstock has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 5410085Abstract: Chlorine-substituted aromatic amines are prepared by the hydrogenation of chlorine-substituted aromatic nitro compounds in the presence of a catalyst containing platinum and nickel and/or cobalt on an activated charcoal support, the platinum having been simultaneously deposited and reduced on the activated charcoal support in the preparation of the catalyst. Such catalysts are furthermore prepared, as are catalysts containing noble metals on an activated charcoal support, it also being possible for the latter to be used for the reduction of nitronaphthalenes or nitrotoluenes.Type: GrantFiled: October 20, 1993Date of Patent: April 25, 1995Assignee: Bayer AktiengesellschaftInventors: Udo Birkenstock, Walter Kipshagen, Herbert Schmidt, Thomas-Jorn Schulz, Eberhard Zirngiebl
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Patent number: 5288894Abstract: Dialkyl carbonates can be prepared by reaction of carbon monoxide with alkyl nitrites in a continuous gas phase reaction, in which a platinum metal catalyst of oxidic or hydroxidic compounds of elements from group Vb of the Periodic Table (Mendeleev) as supports and, if desired, addition of an antimony, bismuth, aluminium, copper, vanadium, niobium, tantalum, tin, iron, cobalt, nickel compound or a mixture of a plurality thereof on this catalyst are used, and the hydrogen halide which is discharged from the reactor together with the reaction mixture is batchwise or continuously replaced in the course of the reaction. This results in the formation of dialkyl carbonates in almost quantitative selectivity; the corresponding dialkyl oxalates can, in most cases, not be detected.Type: GrantFiled: October 8, 1992Date of Patent: February 22, 1994Assignee: Bayer AktiengesellschaftInventors: Heinz Landscheidt, Erich Wolters, Alexander Klausener, Heinz-Ulrich Blank, Udo Birkenstock
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Patent number: 5253993Abstract: An apparatus for the production of pellets of metal powder, more particularly pellets of highly active metal powder, for example Raney catalysts, has a press with a filling shoe and a pellet discharge shoot. A wet processing environment is established and thus no inert gas atmosphere is required to avoid oxidation of the metal powder.Type: GrantFiled: April 15, 1992Date of Patent: October 19, 1993Assignee: Bayer AktiengesellschaftInventors: Udo Birkenstock, Wolfgang Gay, Wolfgang Korsch
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Patent number: 5248840Abstract: To prepare hydroxydiphenyls, a compound or a mixture of several compounds consisting of completely or partly hydrogenated hydroxydiphenyl is dehydrogenated catalytically in the gas phase, a catalyst being employed which comprises, as the active constituents, a combination of rhodium and one or more other platinum metal(s) from the group comprising platinum, palladium, ruthenium and iridium, and which comprises, as promoters, one or more alkali metal hydroxides and/or alkali metal sulphates, the support of which comprises chromium and manganese.Type: GrantFiled: September 24, 1992Date of Patent: September 28, 1993Assignee: Bayer AktiengesellschaftInventors: Otto Immel, Gerhard Darsow, Udo Birkenstock
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Patent number: 5231213Abstract: Dialkyl carbonates can be prepared by reaction of carbon monoxide with alkyl nitrites in continuous gas phase reaction, in which a platinum metal halide catalyst on aluminum oxides, aluminum oxide hydrates or aluminum hydroxides as support and, if desired, an additive comprising an antimony, bismuth, aluminum, copper, vanadium, niobium, tantalum, tin, iron, cobalt, nickel compound or a mixture of a plurality thereof on this catalyst are used and hydrogen halide is replaced during the course of the reaction batchwise or continuously in at least the amount which is discharged from the reactor together with the reaction mixture. This results in the formation of dialkyl carbonates in almost quantitative selectivity, while the corresponding dialkyl oxalates can not in most cases be detected. The abovementioned supports are characterized by a BET surface area of more than 1 m.sup.2 /g.Type: GrantFiled: July 8, 1992Date of Patent: July 27, 1993Assignee: Bayer AktiengesellschaftInventors: Heinz Landscheidt, Alexander Klausener, Erich Wolters, Heinz U. Blank, Udo Birkenstock
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Patent number: 5135903Abstract: The invention relates to a process and an apparatus for the production of pellets of metal powder, more particularly pellets of highly active metal powder, for example Raney catalysts.According to the invention, no inert gas atmosphere is required to avoid oxidation of the metal powder. The pellets are produced by direct press molding of the suspension in a wet environment.The invention also relates to the use of catalyst pellets thus produced in trickle-phase and gas-phase processes.Type: GrantFiled: August 5, 1991Date of Patent: August 4, 1992Assignee: Bayer AktiengesellschaftInventors: Udo Birkenstock, Wolfgang Gay, Wolfgang Korsch
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Patent number: 5135665Abstract: Multichamber-candle filter element for filtration of a residual volume of a suspension with rapidly settling solid components, includes at least two chambers (1,2) positioned in succession above each other, a lowest of the chambers being from 1/3 to 1/10 of a total length of the candle filter element, and a separate filtrate delivery pipe (8,9) extending into each of the chambers to provide a separate filtrate outlet for each chamber and a partition member separating each of the chambers from each other in a fluid-tight manner. The multi-candle filter element also has a fluid-tight cover plate (6) and a fluid-tight bottom plate (3) and fluid permeable walls (14,15).Type: GrantFiled: April 1, 1991Date of Patent: August 4, 1992Assignees: DRM, Dr. Muller AG, Bayer AktiengesellschaftInventors: Udo Birkenstock, Wolfgang Gay, Glenn Hohle
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Patent number: 5120875Abstract: In the preparation of chlorinated aromatic amines by reaction of corresponding nitro compounds with hydrogen under pressure, at elevated temperature and in the presence of a solvent and small amounts of a basic compound, fewer by-products are formed by using platinum and nickel and/or cobalt on an active charcoal support.Type: GrantFiled: August 13, 1990Date of Patent: June 9, 1992Assignee: Bayer AktiengesellschaftInventors: Udo Birkenstock, Ulrich Kappler, Herbert Schmidt, Jurgen Zander
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Patent number: 5090997Abstract: In an advantageous process for producing powdered aluminium alloys which have a catalytic action or are capable of acting as precursors of catalysts, good results are obtained if the alloy is atomized with water and/or a gas at a temperature of 50.degree. to 500.degree. C. above its melting point and then cooled and dried.Type: GrantFiled: January 11, 1991Date of Patent: February 25, 1992Assignees: Bayer Aktiengesellschaft, Hermann C. Starck Berlin GmbH & Co. KGInventors: Udo Birkenstock, Jurgen Scharschmidt, Peter Kunert, Helmut Meinhardt, HaPaul, Paul Meier
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Patent number: 4792626Abstract: Aromatic diamino compounds are produced by hydrogenating the corresponding dinitro compounds in the presence of a modified Raney catalyst. The modified Raney catalyst is obtained by treating an alloy made up of 50-95 wt % of aluminum, 4-45 wt % nickel and/or cobalt and 1-46 wt % of at least one modifying metal with an alkali material. The modifying metal is selected from the metals of the first, fourth, fifth, sixth, seventh and eighth subgroups of the Periodic Table of Elements. The hydrogenation is preferably carried out at from 170.degree. to 250.degree. C. and a pressure of 15-50 bar. The heat generated during hydrogenation is preferably used to produce steam.Type: GrantFiled: October 10, 1986Date of Patent: December 20, 1988Assignee: Bayer AktiengesellschaftInventors: Dieter Becher, Udo Birkenstock, Eckart Waldau, Harro Witt
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Patent number: 4774221Abstract: Supported catalysts containing palladium on a support material are improved by added bases which remain on the material. These supported catalysts are useful for hydrogenating optionally substituted phenols to give the corresponding cyclohexanols as the predominant product.Type: GrantFiled: October 20, 1986Date of Patent: September 27, 1988Assignee: Bayer AktiengesellschaftInventors: Harald Medem, Udo Birkenstock, Herbert Schmidt, Burkhard Lachmann
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Patent number: 4764498Abstract: In the new shaped articles a hollow space or a lumpy inorganic base material is surrounded by a porous silica-containing layer. They can be prepared by applying silica sol or a mixture containing water, silica sol and/or waterglass and, if appropriate, finely pulverulent water-insoluble silica and/or porosity producing agents to a lumpy base material, and, if use is made of organic base materials, then removing these organic base materials by heating. The new shaped articles can be used as support material for catalysts or, if the layer containing the porous silica contains catalytically active substances, as catalysts.Type: GrantFiled: October 28, 1985Date of Patent: August 16, 1988Assignee: Bayer AktiengesellschaftInventors: Adolf Wissner, Josef Haydn, Udo Birkenstock
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Patent number: 4407733Abstract: A process for the preparation of a supported catalyst containing a catalytically active metal such as a noble metal is disclosed wherein the supported catalyst is prepared by initially contacting the inert support with a base and disposing an amount of base in the support corresponding to 0.01 to 50 gram equivalents of base per gram equivalent of catalytically active metal to be deposited thereon, drying the so-treated support to a residual moisture content of less than 10 percent of the maximum absorbency of the support and thereafter impregnating the same with a salt solution of a catalytically active metal, e.g., a salt of a catalytically active noble metal. The inert support is one having a BET surface area of less than 20 square meters per gram. The catalyst is useful in hydrogenation, dehydrogenation, hydrogenolysis, oxidation, polymerization, isomerization or cyclization reactions.Type: GrantFiled: July 20, 1981Date of Patent: October 4, 1983Assignee: Bayer AktiengesellschaftInventors: Udo Birkenstock, Herbert Schmidt
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Patent number: 4265834Abstract: A process for the hydrogenation of nitrobenzene to aniline is described wherein the nitrobenzene is contacted with hydrogen in the presence of a multi-component supported catalyst containing 1 to 20 grams of noble metal per liter of support and 1 to 20 grams per liter of support of one or more transition metal of the Groups IVa, Va, or VIa of the Periodic Table. The catalyst can contain 1 to 20 grams per liter of support of a further transition group element or of a member of the main group. The catalyst is one which has been prepared by a process involving pretreatment of the support with a base prior to impregnation with the catalytically active substances, followed by drying to a residual moisture content of less than 10 percent of the maximum absorbency of the support.Type: GrantFiled: August 16, 1979Date of Patent: May 5, 1981Assignee: Bayer AktiengesellschaftInventors: Udo Birkenstock, Burkhard Lachmann, Josef Metten, Herbert Schmidt
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Patent number: 4224248Abstract: A process has been developed for the depyrophorization of pyrophoric metal catalysts, such as Raney nickel catalysts, which comprises treating said pyrophoric metal catalysts in water and/or an organic solvent with an organic nitro compound or a nitroso compound. The catalysts which are obtained according to the process of the invention are useful for carrying out all hydrogenation reaction which can be carried out using the corresponding pyrophoric catalysts. The catalysts obtained are further distinguished by high activity and extended life. They are not contaminated by contact catalyst poisons and can be used essentially without pre-activation.Type: GrantFiled: October 17, 1978Date of Patent: September 23, 1980Assignee: Bayer AktiengesellschaftInventors: Udo Birkenstock, Josef Haydn
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Patent number: 4176092Abstract: A process has been developed for the depyrophorization of pyrophoric metal catalysts, such as Raney nickel catalysts, which comprises treating said pyrophoric metal catalysts in water and/or an organic solvent with an organic nitro compound or a nitroso compound. The catalysts which are obtained according to the process of the invention are useful for carrying out all hydrogenation reaction which can be carried out using the corresponding pyrophoric catalysts. The catalysts obtained are further distinguished by high activity and extended life. They are not contaminated by contact catalyst poisons and can be used essentially without pre-activation.Type: GrantFiled: June 13, 1977Date of Patent: November 27, 1979Assignee: Bayer AktiengesellschaftInventors: Udo Birkenstock, Josef Haydn
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Patent number: 4059627Abstract: An improvement in a process for the preparation of chlorinated aromatic amines by hydrogenation of the corresponding chlorinated nitro-aromatic compounds in the presence of a noble metal catalyst on a carbon support and in the presence of a sulfur compound, the improvement residing in that the sulfur compound is a thio-ether. Preferably the reaction is carried out in a weakly basic medium.Type: GrantFiled: November 1, 1976Date of Patent: November 22, 1977Assignee: Bayer AktiengesellschaftInventors: Helmuth Kritzler, Walter Bohm, Wolfgang Kiel, Udo Birkenstock