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Showing 1 to 20 of 32 for “"Iron Catalyst"”.
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Statistical Methods For Kinetic Modeling Of Fischer Tropsch Synthesis On A Supported Iron Catalyst
… feedstocks from biomass, coal, or natural gas. Iron catalysts are ideal for conversion of coal and biomass. However, precipitated iron catalysts used in slurry-bubble column reactors suffer from high attrition resulting in difficulty separating catalysts from product and increased slurry …
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Increasing the Stability and Turnover Number of a Highly Active Iron Catalyst for the Asymmetric Transfer Hydrogenation of Ketones
A highly active iron catalyst for the asymmetric transfer hydrogenation (ATH) of ketones was reported by the Morris group in 2013. This catalyst surpassed the activity of platinoid metals by reaching TOFs up to 200 per second, but the highest reported turnover number (TON) was only 6060. To compete …
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The influence of low levels of alumina on the attrition resistance and Fischer-Tropsch synthesis performance of a precipitated iron catalyst
… of alumina as a binder to a spray-dried, iron-based Fischer-Tropsch catalyst was investigated. Alumina was either added during the precipitation or just prior to spray-drying in the form of aluminium nitrate.
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Influence of basicity in Fischer-Tropsch synthesis over supported iron-based catalysts
The Fischer-Tropsch synthesis catalyzed by iron is a well-established process for the production of synthetic fuels, waxes and high-value chemicals, such as α-olefins. A draw-back of the currently used iron-based catalysts is their short lifetime, caused by sintering and particle break-up. These …
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Oxygenates in iron Fischer-Tropsch synthesis : is copper a selectivity promoter?
… them. Commercially, a supported precipitated iron catalyst promoted with small amounts of potassium and copper is one of the catalysts used in this reaction. Precipitated iron catalysts are chemically promoted with potassium in order to enhance the product selectivity, while copper is added as …
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The effect of CO2 on the activation of a precipitated iron Fischer-Tropsch catalyst
… of CO2 on the activation of a precipitated iron catalyst by hydrogen and carbon monoxide was investigated. The iron-based catalyst was precipitated from a mixture of iron nitrate and copper nitrate then bounf by the addition of potassium waterglass to achieve a final catalyst precursor …
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Development of a microreactor system for unsteady-state Fischer- Tropsch synthesis
… aimed at preventing carbon deposition on a fused-iron catalyst in a novel reactor called the “heat-tray.” This reactor involves a supernatant gas flowing over a shallow fluidized bed of catalyst particles. Three systems were built: (1) a vibrofluidized-bed microreactor system for obtaining …
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The use of hydrotalcite derived catalyst precursors in the Fischer-Tropsch synthesis
The current fused iron catalyst used in the high temperature Fischer-Tropsch process is not very responsive to chemical promotion. Thus the optimisation of the selectivity of this catalyst is restricted. In the development of a catalyst the aim is to obtain the best combination of activity, …
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The effect of copper as a chemical promoter on the performance of a cobalt based Fischer-Tropsch synthesis catalyst
… fact 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, …
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Nitrogen-containing compounds from ammonia co-feed to the Fischer-Tropsch synthesis
… an unsupported, potassium-promoted, precipitated iron catalyst. The process is subjected to various ammonia contents in the feed.
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INVESTIGATIONS IN IRON, COPPER, AND PALLADIUM –CATALYZED C-H BOND FUNCTIONALIZATION
… that allow functionalization of C-H bonds via iron and copper catalysis have been developed. Additionally, functionalization of sp3 C-H bonds in amino acid derivatives using auxiliary-assisted palladium-catalyzed methodology is also demonstrated. A method for iron-catalyzed alkylation of arenes …
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Increasing carbon nanotube forest density
… the preparation of a substrate with (typically iron) catalyst nanoparticles (NPs), which become nucleation sites for CNTs. This research was primarily focused on tuning the catalyst/substrate interfacial interactions in order to promote higher NP areal densities. A variety of density-enhancing …
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Effects of catalyst pretreatment for carbon nanotube growth
The effects of pretreatment of iron catalyst for carbon nanotube (CNT) growth was studied. CNTs were grown on Fe/A1203 (1/10 nm) thin-film catalyst deposited on silicon substrates via exposure to C2H4 in a thermal chemical vapor deposition (CVD) furnace. During CVD, the sample was exposed to a …
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Investigation of the promotional effect of Cu and Ag on iron-based Fischer-Tropsch catalysts using ferrites as model catalysts
… metals for industrial application are cobalt and iron. The commercially used iron-based Fischer-Tropsch catalyst is supported on silica (Si), to improve the dispersion of the active metal and is promoted with small amounts of potassium to enhance the activity and selectivity of the catalyst and …
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Novel empowered supports for iron-based Fischer-Tropsch in a power-to-liquids process
… process takes place in the presence of a catalyst, at moderate temperatures and pressures. Iron-based catalysts are frequently used in commercial FT as they are quite useful in hydrogen lean synthesis gas because of their high water-gas shift activity. Nevertheless, these catalysts often …
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Selective area synthesis of 3-D carbon nanotube forest microsctructures
… independently patterned with regions of alumina, iron, or alumina and iron. The CVD process of both techniques require a catalyst nanoparticle to facilitate CNT growth and a hydrocarbon gaseous precursor. Floating catalyst CVD, a process in which CNT catalyst is delivered to a substrate in the …
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An Investigation of the destruction of ion exchange resins
… of Fenton's Reagent (Hydrogen Peroxide/soluble Iron catalyst) to destroy the resin by wet oxidation has been developed. This process converts 95% of the solid resin to gaseous CO2, thus greatly reducing the volume of radioactive waste that has to be disposed of. However, hydrogen peroxide is an …
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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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Synthesis and electrochemical characterization of carbon nanotube forests on metal foils for battery electrodes
… explored as a scalable method to pattern CNT catalyst. In this thesis, the CNT-based electrode is fabricated by growing vertically aligned CNTs on a copper foil using chemical vapor deposition, and depositing the active material, iron phosphate (FP), conformally onto the CNTs using atomic …
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C—H oxidation reactions: development and application
… as well as applications of a biomimetic non-heme iron catalyst towards generating diverse oxidation products and exploring biological pathways. Linear allylic amines are a common motif found in many organic molecules; however, their synthesis involves a lengthy, multi-step sequence that exposes …
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