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Showing 1 to 20 of 21 for “"Cobalt Catalyst"”.
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DEVELOPMENT OF SUPPORTED COBALT CATALYST FOR FISCHER-TROPSCH SYNTHESIS
… chemicals. Understanding and developing FTS catalysts using mesoporous materials are of main interest in the present work. In the first step, the research focused on developing Co-based catalyst supported on multiwalled carbon nanotubes (MWCNTs). The functionalization of CNTs and its impact …
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Low pressure ammonia oxidation over supported cobalt catalyst for nitric acid production
… equipment. Platinum gauze is typically used as a catalyst operating at high temperatures (in the range of 810-940 ᵒC). The platinum based catalyst is highly active and highly selective in producing the desired NOₓ products, with some formation of the undesired byproducts, i.e. N₂, N₂O and N₂O₄. …
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Utilization of cobalt catalyst for high temperature Fischer-Tropsch synthesis in a fluidized bed reactor
… bed reactor (FBR) will allow the use of cobalt catalyst for high temperature Fischer-Tropsch 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 …
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The effect of copper as a chemical promoter on the performance of a cobalt based Fischer-Tropsch synthesis catalyst
… that copper is used as a promoter for the iron catalyst and that the industry is looking at a commercial FT synthesis cobalt catalyst, it is essential to reinvestigate the effect of copper on a cobalt catalyst. Copper has an effect on the overall activity of iron and cobalt [Kolbel, 1951, J. …
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Fundamental understanding of re-dispersion of cobalt on supported model Fischer-Tropsch catalysts
… steps (OROR) for a model supported-cobalt catalyst to give insight into the regeneration process of a spent supported-cobalt FTS catalyst.
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The performance of structured cobalt catalysts in Fischer-Tropsch synthesis
Cobalt is the preferred catalyst metal for the production of clean burning, high cetane number diesel fuel from synthesis gas using the Fischer-Tropsch synthesis. Hence, increasing C5+ selectivity of cobalt catalysts is one of the hot topics in Fischer-Tropsch synthesis. Internal mass transport …
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The influence of molybdenum and vanadium on the activity and selectivity of a cobalt Fischer-Tropsch catalyst
Fischer-Tropsch catalysts tyically contain metals such as iron, cobalt and ruthenium. In this study a supported cobalt catalyst was used, in which cobalt was put on the support by colloidal impregnation. Some literature on CO hydrogenation indicates that molybdenum oxide and vanadium oxide used as …
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The influence of metal crystallite size of the cobalt Fischer-Tropsch catalyst on the re-oxidation of cobalt with water
Catalyst productivity and selectivity to C5+ hydrocarbons are an important criteria in choice of Fischer-Tropsch catalyst. Cobalt-based catalysts appear to provide the best compromise between performance and cost for the synthesis of hydrocarbons [Iglesia, 1997]. The cobalt-based catalysts can be …
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Catalytic Process for the Conversion of Synthesis gas to Ethanol for Use as an Alternative Fuel
… coal, natural gas and biomass. Rhodium-based catalysts have been found to be the most active/selective for higher alcohols. However, the literature shows that the yields of C2+-alcohols that can be achieved with current catalysts, even the most active/selective, are not practical, typically …
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Design and characterization of zeolite supported cobalt carbonyl catalysts
… are made to recover and separate the soluble catalysts. A heterogeneous system consisting of Co₂(CO)₈ impregnated on zeolites with faujasitic structure has been designed and investigated using a variety of techniques. In situ FTIR spectroscopy and carbon monoxide evolution were used to …
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Cobalt(II) Catalyzed Asymmetric Hydrovinylation of Alkyl- and Trialkylsilyloxy-1,3-Dienes
Cobalt catalysis has become an interest for organometallic and organic chemists over the past forty years as an alternative to more expensive, more toxic, or more unstable known catalysts. The reactions catalyzed by cobalt-complexes range from Diels-Alder and other cyclizations to cross coupling …
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Thermal and oxidative degradation of an aromatic polyamide
… also spun incorporating 100, 200 and 400ppm of a cobalt catalyst and the effect of the metal ions on the oxygen uptake of the fibres was investigated. The results show a consistent increase in the rate of oxygen uptake as the concentration of the cobalt is increased. Furthermore, T.G.A. oxidative …
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Manganese promotion of a Co/SiO2 Fischer-Tropsch catalyst
… that the incorporation of manganese into cobaltbased/silica (SiO2) catalyst influences the activity and selectivity of the FischerTropsch synthesis via the enhancement of CO adsorption and dissociation. The base catalyst is prepared by impregnation (IMPR) of the SiO2 support with …
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Electronic Effects in Multidentate Pyridinol and N-Heterocyclic Carbene Based Ligands for Transition Metal Catalyzed Carbon Dioxide Reduction
The design of new catalysts with high catalytic efficiency and robustness towards carbon dioxide (CO2) reduction is of paramount importance. A full understanding of the requirements for creating a catalyst of this type is a missing gap in the knowledge base which prevents progress in synthesizing …
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Reductions by Cobalt-Catalyzed Production of Hydrogen Gas from NaBH4 in a Two-Chamber System
… in catalytic reductions. In the absence of the cobalt catalyst, the formation of H<sub>2</sub> would be retarded by the increased pH of the aqueous NaBH<sub>4</sub> solution. This methodology has several foreseeable advantages. (1) It eschews the need for obtaining and maintaining hazardous …
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Water selective MFI zeolite membranes for application in the Fischer Tropsch Synthesis
… (FTS) during reaction may allow the use of a cobalt catalyst with crystal size <6 nm hence increasing the catalyst activity. Zeolite membranes are a potential route to in-situ water removal due to their chemical and thermal stability under FTS reaction conditions. Zeolite membranes with a low …
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A study of configurational alternatives of a gas-to-liquids process based on Fischer-Tropsch technology
… wax is prioritized, FTS represents the use of cobalt catalyst in LTFT operation. Where air is used, FTS is run to high conversion in once through mode to avoid the unfavorable economics of recycling nitrogen. After separation of the syncrude, the light fraction is reformed back to syngas in …
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Predicting Transitions in Fischer-Tropsch Reactors
… metal surface, and the lifetime of the catalyst bed largely dictates the process’s economic viability. Predictive computational models can shed light on the mechanisms driving catalyst deactivation. This work focuses particularly on reactors with a titania-supported cobalt catalyst. One …
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Synthesis, characterization, and catalytic reactivity of first-row transition metal CCC pincer complexes
… and 90% of newly developed processes utilize catalysts. Understanding how to improve and create new catalysts is therefore essential to developing new products as well as greener and more efficient processes. One way to improve the environmental impact of these reactions is to move away from …
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Catalytic hydrofunctionalization and small molecule reactivity at a low-valent cobalt center supported by a bis(carbene) CCC pincer ligand
The ubiquity of noble metal catalysts in both industrial and academic settings is a testament to their impressive reactivity, versatility, and modularity. Recent advances in cross-coupling catalyses have principally been achieved with this privileged class of compounds, in large part due to the …
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