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Catalysis Fischer-Tropsch

The increase in industrial and academic research on Fischer-Tropsch catalysis following the Second World War and the oil crises of the 1970s is set to continue as the process is expected to become increasingly important... [Pg.325]

The decarbonylation of oxide-supported metal carbonyls yields gaseous products including not just CO, but also CO2, H2, and hydrocarbons [20]. The chemistry evidently involves the support surface and breaking of C - O bonds and has been thought to possibly leave C on the clusters [21]. The chemistry has been compared with that occurring in Fischer-Tropsch catalysis on metal surfaces [20] support hydroxyl groups are probably involved in the chemistry. [Pg.217]

Morales, F., and Weckhuysen, B. M. 2006. Promotion effects in Co-based Fischer-Tropsch catalysis. Catalysis 19 1 10. [Pg.80]

FIGURE 9.1 General view on Fischer-Tropsch catalysis. [Pg.166]

With the recent development of zeolite catalysts that can efficiently transform methanol into synfuels, homogeneous catalysis of reaction (2) has suddenly grown in importance. Unfortunately, aside from the reports of Bradley (6), Bathke and Feder (]), and the work of Pruett (8) at Union Carbide (largely unpublished), very little is known about the homogeneous catalytic hydrogenation of CO to methanol. Two possible mechanisms for methanol formation are suggested by literature discussions of Fischer-Tropsch catalysis (9-10). These are shown in Schemes 1 and 2. [Pg.136]

Fischer-Tropsch Catalysis by Polystyrene Supported CpCo(C0)2... [Pg.174]

Fischer-Tropsch catalysis, 38 333-334 reaction with metal oxides, 38 311-314 anionic hybrid complex, 38 312 butterfly cluster, 38 312-313... [Pg.104]

Fischer-Tropsch catalysis, 34 71, 38 331-335 C2 oxygenate formation, 38 338 oxide-supported osmium clusters, 38 335 product selectivites, 38 333-334 proton-induced reduction of CO, 38 332-333... [Pg.105]

Fischer-Tropsch catalysis, 30 184—187 solvent properties, 30 369 substrate structure, 30 349-350 correlation... [Pg.187]

Fischer-Tropsch catalysis, 38 332 hydroformylation activity, 38 329-330 in NaY supercages, reversible formation and isomer transformation, 38 374 phosphino polystyrene support, 38 39 reactivity, 38 317-319, 323 ship-in-bottle synthesis in NaY zeolite supercages, 38 368-370... [Pg.189]

A particularly intriguing potential application of this reaction is the upgrading of the products of Fischer-Tropsch catalysis to increase the eventual yield of desirable n-aUcane chain lengths (typically C9-C19). FT catalysis, already practiced on a large scale commercially, may prove to be a key route to the future utilization of coal, biomass, or other nonpetroleum carbon sources (including CO2 reduction powered by solar, wind, or nuclear energy) [51, 52]. [Pg.145]

The first, made by Ichikawa et al. [29], was the evidence that rhodium or iridium cluster carbonyls, when adsorbed on zinc oxide, titania, lanthanum oxides, zirconia or magnesia, could produce quite selectively ethanol by the Fischer-Tropsch synthesis. This was a timely discovery (metallic catalytic particles produced by traditional methods could not reproduce such selectivity) since it came at a period of geopolitical tension after the Kippur war in 1973, which caused the price of crude oil to increase enormously. Therefore, that period was characterized by intense research into selective Fischer-Tropsch catalysis. [Pg.7]

Fischer-Hepp rearrangement, 22 151 Fischer-Tropsch catalysis, by graphite intercalation compounds, 23 318 Fish, arsenic in, 44 150, 167, 168, 170, 180 Fission... [Pg.105]

Studies in these laboratories have resulted in the synthesis and catalytic evaluations on a wide range of perovskites and ion modified homogeneous solid solutions for Fischer-Tropsch catalysis, copper modified spinels for higher alcohol synthesis, ion substituted perovskites for methane activation, alkali modified metal... [Pg.245]

Promotion Effects in Co-based Fischer-Tropsch Catalysis... [Pg.11]

Figure 3 The different modes of action of structural promoters in Co-based Fischer-Tropsch catalysis (a) structural promoter elements can lead to a decreased Co compound formation with the support oxide (b) structural promoter elements can act as an oxidic interface between the supported Co ... Figure 3 The different modes of action of structural promoters in Co-based Fischer-Tropsch catalysis (a) structural promoter elements can lead to a decreased Co compound formation with the support oxide (b) structural promoter elements can act as an oxidic interface between the supported Co ...
Figure 4 The different modes of action of electronic promotors in Co-based Fischer-Tropsch catalysis (A) promoter metal oxide decoration of the cobalt surface (B) the SMSI effect and (C) cobalt-promoter alloy formation... Figure 4 The different modes of action of electronic promotors in Co-based Fischer-Tropsch catalysis (A) promoter metal oxide decoration of the cobalt surface (B) the SMSI effect and (C) cobalt-promoter alloy formation...
A new approach to develop a molecular mechanism for Fischer-Tropsch catalysis based on the use of [Fe2Co(CN)6] and [Fe(HCN)2]3 precursor complexes has been disclosed.509 The former produced mainly liquid aliphatic hydrocarbons, whereas the latter gave waxy aliphatic products. Results acquired by various techniques were interpreted to imply that chain growth proceeds via the insertion of CO into an established metal-carbon bond, that is, a C, catalytic insertion mechanism is operative. It follows that C2 insertion is an unlikely possibility. [Pg.125]

The role of iron clusters in Fischer-Tropsch catalysis has been the focus of considerable studies. Cagnoli et al. have recently studied the role of Fe clusters on silica and alumina supports for methanation.22 Chemisorption, catalysis and Mossbauer spectroscopy experiments were used to study the effect of dispersion and the role of various supports. Although several oxidation states of iron were observed, the focus of this research was on Fe clusters which were found to be on the order of 12 A crystal size. The authors proposed that metal support interactions were greater for silica than alumina supports and that selectivity differences between these catalysts were due to differences in surface properties of silica vs. alumina. Differences in selectivity for Fe/SiC>2 catalysts at different H2/CO ratios were attributed to differences in coadsorption of H2 and CO. Selectivity differences are difficult to explain in such systems even when only one metal is present. [Pg.13]

Normand et al. have studied Pd deposited on several metal oxide supports in reactions of methylcyclopropane hydrogenolysis, 3-methylhexane aromatization, and in Fischer-Tropsch catalysis 23 Three classes of oxides were studied, those that were not reducible such as Re2C>3, those with anion vacancies produced during reduction like Ce02, and those with intrinsic anion vacancies such as nonstoichiometric Pt60h and Tb407. Hydrogenolysis reactions were found to occur on Pd sites whereas aromatization reactions were believed to be... [Pg.13]

Let s see the consequences of this trend for two chemical reactions. One is well studied, the dissociative chemisorption of CO. The other is less well known, but it certainly matters, for it must occur in Fischer-Tropsch catalysis. This is the coupling of two alkyl groups on a surface to give an alkane. [Pg.112]

The authors conducted an experiment (now regarded as classical) in Fischer-Tropsch catalysis that supports this initiation mechanism (3,4). Using isotopes, they demonstrated that the carbon chain-growth reaction can occur from Ci species generated by the dissociation of CO. As shown below, this hypothesis implies that the rate of CO dissociation should be fast and should not control the overall Fischer-Tropsch reaction. [Pg.131]

Recent simulations by Marin and coworkers (56,57) seem to confirm Equations (12b) and (12c). A single-event microkinetics (SEMK ) model was used to analyze data characterizing Fischer-Tropsch catalysis on iron. The authors reported an activation energy of only 57 kj/mol for CO dissociation, whereas activation energies for the chain-growth reaction and termination reaction leading to alkane or alkene formation were found to be 45,118, and 97 kJ/mol, respectively. [Pg.142]


See other pages where Catalysis Fischer-Tropsch is mentioned: [Pg.40]    [Pg.19]    [Pg.174]    [Pg.339]    [Pg.123]    [Pg.143]    [Pg.146]    [Pg.162]    [Pg.164]    [Pg.16]    [Pg.107]    [Pg.11]    [Pg.71]    [Pg.216]    [Pg.127]    [Pg.129]    [Pg.131]    [Pg.135]    [Pg.139]    [Pg.141]   
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See also in sourсe #XX -- [ Pg.137 ]




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Catalysis Fischer-Tropsch process

Fischer-Tropsch catalysis product selectivities

Fischer-Tropsch catalysis, mechanistic

Fischer-Tropsch reaction heterogeneous catalysis

Fischer-Tropsch reaction homogeneous catalysis

Fischer-Tropsch synthesis catalysis

Heterogeneous catalysis Fischer-Tropsch synthesis

Hydrogenation Fischer-Tropsch catalysis

Methanation reaction, Fischer-Tropsch catalysis

Olefins Fischer-Tropsch catalysis

Spectroscopy Fischer-Tropsch catalysis

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