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Enthalpy and entropy barriers explain the effects of topology on the kinetics of zeolite-catalyzed reactions

(2013) CHEMISTRY-A EUROPEAN JOURNAL. 19(35). p.11568-11576
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Abstract
The methylation of ethene, propene, and trans-2-butene on zeolites H-ZSM-58 (DDR), H-ZSM-22 (TON), and H-ZSM-5 (MFI) is studied to elucidate the particular influence of topology on the kinetics of zeolite-catalyzed reactions. H-ZSM-58 and H-ZSM-22 are found to display overall lower methylation rates compared to H-ZSM-5 and also different trends in methylation rates with increasing alkene size. These variations may be rationalized based on a decomposition of the free-energy barriers into enthalpic and entropic contributions, which reveals that the lower methylation rates on H-ZSM-58 and H-ZSM-22 have virtually opposite reasons. On H-ZSM-58, the lower methylation rates are caused by higher enthalpy barriers, owing to inefficient stabilization of the reaction intermediates in the large cage-like pores. On the other hand, on H-ZSM-22, the methylation rates mostly suffer from higher entropy barriers, because excessive entropy losses are incurred inside the narrow-channel structure. These results show that the kinetics of crucial elementary steps hinge on the balance between proper stabilization of the reaction intermediates inside the zeolite pores and the resulting entropy losses. These fundamental insights into their inner workings are indispensable for ultimately selecting or designing better zeolite catalysts.
Keywords
REACTION-MECHANISMS, NITRILE ADSORPTION, METHANOL ADSORPTION, METHYLATION REACTIONS, TO-OLEFIN CONVERSION, MOLECULAR-DYNAMICS SIMULATION, zeolites, ab initio calculations, density functional calculations, methylation, chemical kinetics, SHAPE-SELECTIVITY, DIMETHYL ETHER, ZSM-5 ZEOLITES, H-BETA

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MLA
Van der Mynsbrugge, Jeroen, Jeroen De Ridder, Karen Hemelsoet, et al. “Enthalpy and Entropy Barriers Explain the Effects of Topology on the Kinetics of Zeolite-catalyzed Reactions.” CHEMISTRY-A EUROPEAN JOURNAL 19.35 (2013): 11568–11576. Print.
APA
Van der Mynsbrugge, J., De Ridder, J., Hemelsoet, K., Waroquier, M., & Van Speybroeck, V. (2013). Enthalpy and entropy barriers explain the effects of topology on the kinetics of zeolite-catalyzed reactions. CHEMISTRY-A EUROPEAN JOURNAL, 19(35), 11568–11576.
Chicago author-date
Van der Mynsbrugge, Jeroen, Jeroen De Ridder, Karen Hemelsoet, Michel Waroquier, and Veronique Van Speybroeck. 2013. “Enthalpy and Entropy Barriers Explain the Effects of Topology on the Kinetics of Zeolite-catalyzed Reactions.” Chemistry-a European Journal 19 (35): 11568–11576.
Chicago author-date (all authors)
Van der Mynsbrugge, Jeroen, Jeroen De Ridder, Karen Hemelsoet, Michel Waroquier, and Veronique Van Speybroeck. 2013. “Enthalpy and Entropy Barriers Explain the Effects of Topology on the Kinetics of Zeolite-catalyzed Reactions.” Chemistry-a European Journal 19 (35): 11568–11576.
Vancouver
1.
Van der Mynsbrugge J, De Ridder J, Hemelsoet K, Waroquier M, Van Speybroeck V. Enthalpy and entropy barriers explain the effects of topology on the kinetics of zeolite-catalyzed reactions. CHEMISTRY-A EUROPEAN JOURNAL. 2013;19(35):11568–76.
IEEE
[1]
J. Van der Mynsbrugge, J. De Ridder, K. Hemelsoet, M. Waroquier, and V. Van Speybroeck, “Enthalpy and entropy barriers explain the effects of topology on the kinetics of zeolite-catalyzed reactions,” CHEMISTRY-A EUROPEAN JOURNAL, vol. 19, no. 35, pp. 11568–11576, 2013.
@article{4145542,
  abstract     = {The methylation of ethene, propene, and trans-2-butene on zeolites H-ZSM-58 (DDR), H-ZSM-22 (TON), and H-ZSM-5 (MFI) is studied to elucidate the particular influence of topology on the kinetics of zeolite-catalyzed reactions. H-ZSM-58 and H-ZSM-22 are found to display overall lower methylation rates compared to H-ZSM-5 and also different trends in methylation rates with increasing alkene size. These variations may be rationalized based on a decomposition of the free-energy barriers into enthalpic and entropic contributions, which reveals that the lower methylation rates on H-ZSM-58 and H-ZSM-22 have virtually opposite reasons. On H-ZSM-58, the lower methylation rates are caused by higher enthalpy barriers, owing to inefficient stabilization of the reaction intermediates in the large cage-like pores. On the other hand, on H-ZSM-22, the methylation rates mostly suffer from higher entropy barriers, because excessive entropy losses are incurred inside the narrow-channel structure. These results show that the kinetics of crucial elementary steps hinge on the balance between proper stabilization of the reaction intermediates inside the zeolite pores and the resulting entropy losses. These fundamental insights into their inner workings are indispensable for ultimately selecting or designing better zeolite catalysts.},
  author       = {Van der Mynsbrugge, Jeroen and De Ridder, Jeroen and Hemelsoet, Karen and Waroquier, Michel and Van Speybroeck, Veronique},
  issn         = {0947-6539},
  journal      = {CHEMISTRY-A EUROPEAN JOURNAL},
  keywords     = {REACTION-MECHANISMS,NITRILE ADSORPTION,METHANOL ADSORPTION,METHYLATION REACTIONS,TO-OLEFIN CONVERSION,MOLECULAR-DYNAMICS SIMULATION,zeolites,ab initio calculations,density functional calculations,methylation,chemical kinetics,SHAPE-SELECTIVITY,DIMETHYL ETHER,ZSM-5 ZEOLITES,H-BETA},
  language     = {eng},
  number       = {35},
  pages        = {11568--11576},
  title        = {Enthalpy and entropy barriers explain the effects of topology on the kinetics of zeolite-catalyzed reactions},
  url          = {http://dx.doi.org/10.1002/chem.201301272},
  volume       = {19},
  year         = {2013},
}

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