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Showing 1 to 13 of 13 for “"Heterogene Katalyse"”.
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Photoelektronenspektroskopische Untersuchungen an Mischoxidkatalysatoren
… und damit hochrelevante Daten für die heterogene Katalyse liefert. Die Ergebnisse wurden mit weiteren Messmethoden und Spektroskopiearten ergänzt. Ferner wurden die neu ermittelten Daten und Ergebnisse in den Gesamtkontext schon bestehender Erkenntnisse eingebaut. Trotz weitreichender …
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Methods for the synthesis of linear dialkylaromatic compounds by the use of heterogeneous catalysts
The objective of this work is to discover new heterogeneous catalysts for the production of linear dialkylaromatic compounds such as 4,4'-dimethylbiphenyl, 4,4'diisopropylbiphenyl, 2,6-diisopropylnaphthalene and p-cymene. Essentially this work studies three different catalytic methods. The first …
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Organische Reaktionen an stark sauren Nafion-Silica nanokompositen Katalysatoren
This paper decribes the study on several organic reactions over highly acidic Nafion/Silica catalysts. Via embedding nano-sized Nafion particles within a highly porous silica matrix, a nano-composite catalyst is manufactured, which got tremendously improved desorption and adsorption properties. …
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Heterogeneously catalyzed reactions with vegetable oils : epoxidation and nucleophilic epoxide ring-opening with alcohols
… oils with peracids produced in the presence of heterogeneous acidic catalysts requires low contact between the epoxide and the acidic centers to avoid consecutive reactions. The main by-product is the ketone, obtained from the epoxide rearrangement reaction. Ketone formation is favored by …
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Zur Mikro- und Makrokinetik mehrphasiger heterogen-katalysierter Reaktionssysteme : Untersuchungen am Modellsystem der Ni-katalysierten Hydrierung von 1-Octen
Heterogeneous catalysis based upon multiphase reactions is a very important issue in the chemical industry. Various mass transfer resistances (gas-liquid, liquid-solid, pore diffusion) occur in such systems. This results in the fact that the effective rate of reaction is much lower than the …
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Heterogenkatalysierte elektrophile Addition am Beispiel der Hydratisierung von Ethylen und Alkoxylierung, Acyloxylierung von Oleochemikalien
… fatty acid esters in the presence of acid heterogeneous catalysts. All products could by isolated and identified by GC-MS, IR and 1H - and 13C-NMR. The catalysts involved in the reaction were examined by ICP, BET and 1H-MAS-NMR. Further, the GC-analysis for fatty acid esters was built up …
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Heterogeneous catalysis in the different reactor types on the examples of ethyl benzene to styrene, methane dehydroaromatization and propylene carbonate, methanol transesterification
… projects. Different types of reactors for heterogeneous catalysis were applied in this work – fixed and fluidized bed rectors as well as a riser reactor. Many parameters as e.g. contact times, temperature control, catalyst regeneration procedure etc. can be varied and adjusted to the …
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Flow-through membrane microreactor for intensified heterogeneous catalysis
… several innovative reactor types for heterogeneous catalysis are discussed, including membrane reactors, microreactors and monolithic reactors. A novel reactor concept called flow-through catalytic membrane microchannel reactor contains aspects of each of the three reactor types: The …
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Katalytische Hydrierung in Mehrphasensystemen auf Basis von ionischen Flüssigkeiten und Kohlendioxid
Carbon dioxide (CO2) and ionic liquids (ILs) have been intensively studied as solvents in catalysis. The combination of ILs and CO2 and its interaction with third components has attracted only sparse interest in research. In the literature, the IL/CO2 system is discussed as a promising technique …
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In situ XAS-Untersuchungen zur Partialoxidation von Acrolein an Mischoxidkatalysatoren
Vanadium molybdenum mixed oxides have proven to be active and selective catalysts for the partial oxidation of unsaturated aldehydes. They are widely used in Megaton-scale industrial processes like the partial oxidation of acrolein to acrylic acid. The macroscopic reaction kinetics of vanadium …
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Strukturuntersuchung organischer Moleküle auf Au(111)-Oberflächen
The present work covers two topics namely the coadsorption of formic acid and water on Au(111) and the structure of biphenylalkanthiole SAMs on Au(111) surfaces. The coadsorption of formic acid and water on Au(111) surfaces has been investigated by means of vibrational and photoelectron …
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Enantioselective ring opening reactions catalysed by heterogenized metal salen complexes
… reactions over the by immobilisation prepared heterogeneous materials, selectivity’s and efficiencies comparable to their homogeneous counterparts were obtained. Several limiting factors might play role in the somewhat affected catalytic performance of the heterogenised complexes, such as i.g. …