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Showing 1 to 13 of 13 for “"gamma alumina"”.
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Synthesis and dynamics of [gamma]-alumina supported molybdenum subcarbonyls and model compounds
Molybdenum hexacarbonyl supported on 𝛾-alumina is a precursor to an active olefin metathesis catalyst. Surface sites on the alumina act as coordinating ligands to stabilize various molybdenum subcarbonyl species. The formation of these species can be controlled by appropriate activation conditions. …
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The Surface Reaction Mechanisms of Beta-Diketones on Transition Metal Surfaces Including Applications to Metal Thermal Chemical Vapor Etching and Heterogeneous Catalyst Particle Redispersion
… interactions of beta-diketones was also done on alumina and gamma-alumina supported Pd catalysts in an attempt to alter Pd particle dispersion. Low-temperature redispersion of a sintered 5% Pd/gamma-alumina catalyst was most successful via exposure to oxygen and acetylacetone at ∼560 K for 8 …
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Multinuclear Nuclear Magnetic Resonance Studies of Model Inorganic Systems (Nmr)
… obtain information from molybdenum carbonyl on (gamma)-aluminum, the Group IIIA compounds, Al III and silica hydrolysis. Techniques such as rapid magic-angle sample spinning (MASS) of glass sealed samples are used to investigate the highly air sensitive system molybdenum carbonyl on …
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Experimental and modeling studies on a catalytic packed bed membrane reactor
… was methanol synthesis with BASF catalyst, and a gamma-alumina membrane with a nominal pore size of 40 A was used.;Preliminary experiments were carried out in the membrane reactor without any catalyst inside membrane to characterize it in terms of its flux, permeance, and selectivity of H2 over …
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Utilization of cobalt catalyst for high temperature Fischer-Tropsch synthesis in a fluidized bed reactor
… synthesis (HTFT). Cobalt was loaded onto a gamma alumina support, the catalyst was characterized using TPR, BET/BJH, XRD, and PSA to track changes in the catalyst morphology. The reactor was characterized to determine the minimum fluidization velocity and the maximum velocity prior to …
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Preparation, characterization and testing of inorganic ceramic membranes.
… development involved modification of Alpha Alumina support with Gamma Alumina for improved surface area. Further modifications with Magnesium Oxide and Silicon Elastomer showed increase in the selectivity of Carbon dioxide molecules over Nitrogen, Methane, Argon, and Helium molecules, both …
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Catalytic synthesis of biodiesel fuel under sub/supercritical conditions: kinetics and phase behavior
… in a packed-bed reactor containing unmodified gamma-alumina. A kinetic study suggests that the mass transfer resistance of the esterification reaction was not significant. Both reaction systems were capable of converting the oil feedstocks to biodiesel product in a few minutes with high …
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Structure and Dynamics in Ligand-Protected and Supported Metal Nanoparticles
… absorption spectroscopy studies of sub-nanometer gamma-alumina-supported platinum nanoparticles revealed unprecedented metal-metal bond contraction with increasing temperature. Both the structural and electronic information obtained in the spectroscopic studies suggest that support-particle charge …
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X-RAY CHARACTERIZATION OF PLATINUM GROUP METAL CATALYSTS
… catalyst (palladium on lanthanum-stabilized gamma-alumina) can be obtained through image intensity analysis. Using these techniques we have characterized the state of bimetallic fuel cell catalysts, ex situ, and have examined the state of Pd catalysts under operando CO oxidation conditions.
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Monolith Catalyst Supports for Hydrogen Production
… reforming unit employs ruthenium supported on gamma-alumina (Ru/ -AbOo) catalyst.. However, it has been observed that. upon increasing the sea.le, pressure-drop and mass transfer limitations become significant issues. It is, therefore, desired to shift from packed bed reactors to monolithic …
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A study of active sites on fibrillar alumina catalysts
… nature of active sites on two kinds of fibrous alumina catalysts. The results of this investigation are comparable to results reported in the literature describing similar reactions studied over more conventional forms of gamma alumina. However, there were a few notable exceptions which make it …
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Composite inorganic membranes for hydrogen reaction, separation and purification.
Silica-alumina composite membranes for hydrogen separation and high temperature chemical reactions were prepared using both conventional and modified dip-coating techniques. These were deposited on commercially available a.-alumina macroporous support of 10 millimetre (mm) outer diameter, 7 mm …
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Study of Adsorbate Interactions of Alumina Surfaces Using Nuclear Magnetic Resonance Methods
Gamma type alumina (gamma-Al2O3) is a fundamental material in heterogeneous catalysis with a growing demand for environmentally benign solid acid catalysts to replace toxic and corrosive liquid solvents for a wide range of applications including renewable energy production, fine chemicals and …