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Efficient approach for the computational study of alcohol and nitrile adsorption in H-ZSM-5

(2012) JOURNAL OF PHYSICAL CHEMISTRY C. 116(9). p.5499-5508
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Abstract
Since many industrially important processes start with the adsorption of guest molecules inside the pores of an acidic zeolite catalyst, a proper estimate of the adsorption enthalpy is of paramount importance. In this contribution, we report ab initio calculations on the adsorption of water, alcohols, and nitriles at the bridging Bronsted sites of H-ZSM-5, using both cluster and periodic models to account for the zeolite environment. Stabilization of the adsorption complexes results from hydrogen bonding between the guest molecule and the framework, as well as from embedding, i.e., van der Waals interactions with the pore walls. Large-cluster calculations with different DFT methods, in particular B3LYP(-D), PBE(-D), M062X(-D), and omega B97X-D, are tested for their ability to reproduce the experimental heats of adsorption available in the literature (J. Phys. Chem. B 1997, 101, 3811-3817). A proper account of dispersion interactions is found to be crucial to describe the experimental trend across a series of adsorbates of increasing size, i.e., an increase in adsorption enthalpy by 10-15 kJ/mol for each additional carbon atom. The extended-cluster model is shown to offer an attractive alternative to periodic simulations on the entire H-ZSM-5 unit cell, resulting in virtually identical final adsorption enthalpies. Comparing calculated stretch frequencies of the zeolite acid sites and the adsorbate functional groups with experimental IR data additionally confirms that the cluster approach provides an appropriate representation of the adsorption complexes.
Keywords
INITIO MOLECULAR-DYNAMICS, DENSITY-FUNCTIONAL THEORY, TOTAL-ENERGY CALCULATIONS, DER-WAALS COMPLEXES, SURFACE COMPLEXES, DISPERSION CORRECTIONS, AB-INITIO, ACIDIC ZEOLITES, ZSM-5 ZEOLITES, WAVE BASIS-SET

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Citation

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Chicago
Van der Mynsbrugge, Jeroen, Karen Hemelsoet, Matthias Vandichel, Michel Waroquier, and Veronique Van Speybroeck. 2012. “Efficient Approach for the Computational Study of Alcohol and Nitrile Adsorption in H-ZSM-5.” Journal of Physical Chemistry C 116 (9): 5499–5508.
APA
Van der Mynsbrugge, J., Hemelsoet, K., Vandichel, M., Waroquier, M., & Van Speybroeck, V. (2012). Efficient approach for the computational study of alcohol and nitrile adsorption in H-ZSM-5. JOURNAL OF PHYSICAL CHEMISTRY C, 116(9), 5499–5508.
Vancouver
1.
Van der Mynsbrugge J, Hemelsoet K, Vandichel M, Waroquier M, Van Speybroeck V. Efficient approach for the computational study of alcohol and nitrile adsorption in H-ZSM-5. JOURNAL OF PHYSICAL CHEMISTRY C. 2012;116(9):5499–508.
MLA
Van der Mynsbrugge, Jeroen, Karen Hemelsoet, Matthias Vandichel, et al. “Efficient Approach for the Computational Study of Alcohol and Nitrile Adsorption in H-ZSM-5.” JOURNAL OF PHYSICAL CHEMISTRY C 116.9 (2012): 5499–5508. Print.
@article{2082545,
  abstract     = {Since many industrially important processes start with the adsorption of guest molecules inside the pores of an acidic zeolite catalyst, a proper estimate of the adsorption enthalpy is of paramount importance. In this contribution, we report ab initio calculations on the adsorption of water, alcohols, and nitriles at the bridging Bronsted sites of H-ZSM-5, using both cluster and periodic models to account for the zeolite environment. Stabilization of the adsorption complexes results from hydrogen bonding between the guest molecule and the framework, as well as from embedding, i.e., van der Waals interactions with the pore walls. Large-cluster calculations with different DFT methods, in particular B3LYP(-D), PBE(-D), M062X(-D), and omega B97X-D, are tested for their ability to reproduce the experimental heats of adsorption available in the literature (J. Phys. Chem. B 1997, 101, 3811-3817). A proper account of dispersion interactions is found to be crucial to describe the experimental trend across a series of adsorbates of increasing size, i.e., an increase in adsorption enthalpy by 10-15 kJ/mol for each additional carbon atom. The extended-cluster model is shown to offer an attractive alternative to periodic simulations on the entire H-ZSM-5 unit cell, resulting in virtually identical final adsorption enthalpies. Comparing calculated stretch frequencies of the zeolite acid sites and the adsorbate functional groups with experimental IR data additionally confirms that the cluster approach provides an appropriate representation of the adsorption complexes.},
  author       = {Van der Mynsbrugge, Jeroen and Hemelsoet, Karen and Vandichel, Matthias and Waroquier, Michel and Van Speybroeck, Veronique},
  issn         = {1932-7447},
  journal      = {JOURNAL OF PHYSICAL CHEMISTRY C},
  keyword      = {INITIO MOLECULAR-DYNAMICS,DENSITY-FUNCTIONAL THEORY,TOTAL-ENERGY CALCULATIONS,DER-WAALS COMPLEXES,SURFACE COMPLEXES,DISPERSION CORRECTIONS,AB-INITIO,ACIDIC ZEOLITES,ZSM-5 ZEOLITES,WAVE BASIS-SET},
  language     = {eng},
  number       = {9},
  pages        = {5499--5508},
  title        = {Efficient approach for the computational study of alcohol and nitrile adsorption in H-ZSM-5},
  url          = {http://dx.doi.org/10.1021/jp2123828},
  volume       = {116},
  year         = {2012},
}

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