[article]
Titre : |
Comparative simulations of cobalt- and iron-based Fischer-Tropsch synthesis slurry bubble column reactors |
Type de document : |
texte imprimé |
Auteurs : |
I. Iliuta, Auteur ; F. Larachi, Auteur ; J. Anfray, Auteur ; N. Dromard, Auteur |
Année de publication : |
2008 |
Article en page(s) : |
p. 3861–3869 |
Note générale : |
Bibliogr. p. 3869 |
Langues : |
Anglais (eng) |
Mots-clés : |
Iron Cobalt Fischer-Tropsch synthesis |
Résumé : |
The influence of the catalyst type (Fe and Co) on CO and H2 conversions, CO2 selectivity, and the composition in Fischer-Tropsch synthesis slurry bubble column reactors was simulated for representative commercial-scale units (7 m i.d. and 30 m height). A nonisothermal, core-annulus multicompartment multicomponent two-bubble class model was used to account for a relatively detailed hydrodynamics. It was coupled to comprehensive Fischer-Tropsch synthesis and water−gas-shift reactions, in addition to descriptions of thermodynamics and thermal effects, variable gas flow rate due to chemical/physical contraction, and gas and slurry backmixing and (re)circulation. Two mechanistic kinetic models with consideration of olefin readsorption were employed to describe the paraffin and olefin formation with cobalt- and iron-based catalysts, in addition to relatively large activities for CO2 and oxygenate formation, mainly alcohols, for the latter catalyst. The influence of the temperature and superficial gas velocity on CO and H2 conversions was more evident for a cobalt-based catalyst. For both catalysts, the space-dependent superficial gas velocity directly affected the gas-phase mean residence time, influencing in the return reactor temperature and conversions. Reliable estimation of the gas velocity due to chemical contraction was critical for conversions exceeding 50%. For both catalysts, the nonisothermal simulations reveal that, because heat removal is well managed from the heat-exchange area, the reactor operation can be considered as nearly isothermal. |
En ligne : |
http://pubs.acs.org/doi/abs/10.1021/ie701764y |
in Industrial & engineering chemistry research > Vol. 47 n°11 (Juin 2008) . - p. 3861–3869
[article] Comparative simulations of cobalt- and iron-based Fischer-Tropsch synthesis slurry bubble column reactors [texte imprimé] / I. Iliuta, Auteur ; F. Larachi, Auteur ; J. Anfray, Auteur ; N. Dromard, Auteur . - 2008 . - p. 3861–3869. Bibliogr. p. 3869 Langues : Anglais ( eng) in Industrial & engineering chemistry research > Vol. 47 n°11 (Juin 2008) . - p. 3861–3869
Mots-clés : |
Iron Cobalt Fischer-Tropsch synthesis |
Résumé : |
The influence of the catalyst type (Fe and Co) on CO and H2 conversions, CO2 selectivity, and the composition in Fischer-Tropsch synthesis slurry bubble column reactors was simulated for representative commercial-scale units (7 m i.d. and 30 m height). A nonisothermal, core-annulus multicompartment multicomponent two-bubble class model was used to account for a relatively detailed hydrodynamics. It was coupled to comprehensive Fischer-Tropsch synthesis and water−gas-shift reactions, in addition to descriptions of thermodynamics and thermal effects, variable gas flow rate due to chemical/physical contraction, and gas and slurry backmixing and (re)circulation. Two mechanistic kinetic models with consideration of olefin readsorption were employed to describe the paraffin and olefin formation with cobalt- and iron-based catalysts, in addition to relatively large activities for CO2 and oxygenate formation, mainly alcohols, for the latter catalyst. The influence of the temperature and superficial gas velocity on CO and H2 conversions was more evident for a cobalt-based catalyst. For both catalysts, the space-dependent superficial gas velocity directly affected the gas-phase mean residence time, influencing in the return reactor temperature and conversions. Reliable estimation of the gas velocity due to chemical contraction was critical for conversions exceeding 50%. For both catalysts, the nonisothermal simulations reveal that, because heat removal is well managed from the heat-exchange area, the reactor operation can be considered as nearly isothermal. |
En ligne : |
http://pubs.acs.org/doi/abs/10.1021/ie701764y |
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