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Showing 1 to 20 of 20 for “"Fischer-Tropsch process."”.
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Recycling the tail-gas during the low temperature Fischer-Tropsch process
… economically viable operation of an iron-based Fischer-Tropsch technology, two options are available: (i) use a diluted feed, such as nitrogenrich synthesis gas, thereby saving on synthesis gas costs [Jess et aI., 1999] or (ii) recycle of the unconverted synthesis gas that leaves the reactor, …
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Selective production of nitrogen-containing compounds via a modified Fischer-Tropsch process
Research on the co-feeding of ammonia into the Fischer-Tropsch (FTS) process over ironbased catalysts revealed that the presence of ammonia during the FTS leads to the formation of nitrogen-containing compounds (NCCs). Recent studies on the addition of ammonia to the FTS process, now known as the …
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The addition of HZSM-5 to the Fischer-Tropsch process for improved gasoline production
The Fischer-Tropsch process has two important disadvantages with regard to the production of gasoline. Firstly, the carbon number distribution of the product spectrum follows the statistical Schulz-Flory function. This means that principally hydrocarbons of all lengths are produced and that the …
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Carbidization and size effects of unsupported nanosized iron in the low temperature Fischer-Tropsch process
In the process of developing the most efficient production of fuels from coal or natural gas, there have been major advances in the development of the catalysts used. Previous work at the Centre for Catalysis Research, at the University of Cape Town, has shown great potential and provided a much …
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The effect of activation on the deactivation of a precipitated iron based catalyst
There has been renewed interest in the Fischer-Tropsch process since diesel fuel derived from natural gas Fischer-Tropsch processes can meet the proposed future legislation standards for sulphur emissions without further processing. Oil refineries producing diesel fuel on the other hand would have …
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The use of hydrotalcite derived catalyst precursors in the Fischer-Tropsch synthesis
… 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, selectivity and …
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A novel method to evaluate synthetic fuel options for gas turbines in terms of O-ring swelling
… Sasol produces fully synthetic jet fuel from its Fischer-Tropsch process and the latter is the source of synthesised paraffinic kerosene (SPK). SPK typically contain iso paraffins and small quantities of normal paraffins. However, they do not contain heteroatomic species or aromatic compounds. …
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Design and characterization of zeolite supported cobalt carbonyl catalysts
… thermolysis were also found to be active Fischer-Tropsch catalysts. Major products observed in the carbonylation of methanol were methyl acetate and an acetaldehyde dimethyl acetal. The supported cobalt catalyst displays greater activity than Co₂(CO)₈ in solution for the carbonylation …
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Studies of Carbon Dioxide Methanation and Related Phenomena in Porous Catalysts
… Separately a CO hydrogenation reaction, the Fischer-Tropsch process, was modelled numerically to examine the influence of mass transfer in practical, commercial pellets of catalyst. The kinetics of methanation was investigated for Ni/γ-Al2O3 over a wide range of reactant partial pressures …
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Aromatization of alkenes by gallium/H-ZSM-5 zeolite catalysts
… plant, based on a technology called the Cyclar process, used continuous catalyst regeneration (CCR) and a gallium impregnated ZSM-5 zeolite catalyst to achieve yields of ca. 65% aromatics, mainly benzene, toluene and xylenes (BTX) [Guisnet and Gnep, 1992]. As a result of the Fischer-Tropsch …
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Carbon Dioxide Gas Separation from Syngas to Increase Conversion of Reverse Water Gas Shift Reaction via Polymeric and Mixed Matrix Membranes
… the overall conversion of CO2 to CO. This process involves a separation and recycling process to reuse the unreacted CO2 from the RWGS reactor. The carbon monoxide produced from this reaction, alongside hydrogen (composing syngas), can be used in the Fischer-Tropsch process to create …
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Aromatization over platinum/zeolite L catalysts : the effect of oxygenates
… exhibits excellent stability and the Aromax Process developed by Chevron Ltd., using I a barium doped Pt/KL catalyst, PtBa/KL, has been reported to operate continually for the equivalent of one year during accelerated deactivation testing at 450°C and a hydrogen partial pressure of 6 bar. …
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Synthesis, characterisation, and evaluation of supported cobalt molybdenum nitride for Fischer-Tropsch reaction
Fischer-Tropsch Synthesis (FTS) is known as the most practical way to convert natural gas to hydrocarbon products including synthetic fuel depending on the catalysts and operating conditions. Australia has 25% of world's natural gas resources hence Australia's crude oil dependency can be reduced …
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Earth-Abundant Metal Complexes Binding N-Heterocyclic Carbene-Based Ligands for the Photocatalytic Carbon Dioxide Reduction Reaction
… CO could be used to produce diesel fuels via the Fischer-Tropsch process. However, a robust and efficient earth-abundant transition metal-based photocatalyst for CO2 reduction reaction is needed to achieve this goal. N-heterocylic carbene (NHC) ligands have been used widely in organometallic …
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Alumina-modified cobalt catalysts for the Fischer-Tropsch synthesis
In the Fischer-Tropsch process, valuable hydrocarbons are produced using the basic starting materials hydrogen and carbon monoxide, which can be derived from alternative carbon sources such as coal, gas or biomass [1]. Although this process has been studied for almost a century, the effects of the …
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Vibrational and anion photoelectron spectroscopy of transition metal clusters
… ruthenium as catalyst for CO methanation in the Fischer-Tropsch process, the composition and structures of saturated cationic ruthenium carbonyls are studied. Their IR spectra are obtained in the range of the C-O stretches, Ru-CO stretches and deformation modes. Structural assignment is achieved …
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Predicting Transitions in Fischer-Tropsch Reactors
The Fischer-Tropsch process has the potential to be fundamental to a future without dependence on fossil fuels. It converts syngas, a readily available resource, into high quality hydrocarbons, with water being the primary byproduct. Like many gas-to-liquid processes, it is catalysed on a …
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Dendritic rhodium catalyst precursors for the hydroformylation of olefins
… renewable feedstocks such as olefins from the Fischer-Tropsch process. Rhodium is the metal of choice when designing catalysts for hydroformylation, owing to its good catalytic activity under mild reaction conditions. The strategy of appending bulky ligands has often been employed to enhance …
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Perovskites as New Support Materials for the Iron Based Fischer-Tropsch Synthesis
In the Fischer-Tropsch process, valuable products consisting mainly of long chain hydrocarbons and water as by-product are synthesized from the basic starting materials hydrogen and carbon monoxide, derived from sources such as coal, gas or biomass [1]. Iron catalysts and cobalt based systems are …
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Waste to fuel: designing a cobalt based catalyst and process for once-through Fischer-Tropsch synthesis operated at high conversion
… liquid fuel security of Sub-Saharan Africa. The Fischer-Tropsch process can be used to convert waste into drop-in fuels. However, operating at small scale in remote locations requires a plant design with lower capital requirements, a greater level of simplicity and utility self-sufficiency. A …