Van't Hoff law for temperature dependent Langmuir constants in clathrate hydrate nanocavities

Azzedine Lakhlifi; Pierre Richard Dahoo

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arXiv · 1503.04633

Van't Hoff law for temperature dependent Langmuir constants in clathrate hydrate nanocavities

Azzedine Lakhlifi·Pierre Richard Dahoo

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Abstract

This work gives a van't Hoff law expression of Langmuir constants of different species for determining their occupancy in the nanocavities of clathrate hydrates. The van't Hoff law's parameters are derived from a fit with Langmuir constants calculated using a pairwise site-site interaction potential to model the anisotropic potential environment in the cavities, as a function of temperature. The parameters can be used for calculating clathrates compositions. Results are given for nineteen gas species trapped in the small and large cavities of structure types I and II [1]. The accuracy of this approach is based on a comparison with available experimental data for ethane and cyclo- propane clathrate hydrates. The numerical method applied in this work, was recently validated from a comparison with the spherical cell method based on analytical considerations [1]

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Azzedine Lakhlifi, Pierre Richard Dahoo. 2015-03-16. Van't Hoff law for temperature dependent Langmuir constants in clathrate hydrate nanocavities. https://arxiv.org/abs/1503.04633

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