Modification of the van der Waals and Platteeuw model for gas hydrates considering multiple cage occupancy

0583558 - ÚT 2025 RIV US eng J - Journal Article
Fiedler, F. - Vinš, Václav - Jäger, A. - Span, R.
Modification of the van der Waals and Platteeuw model for gas hydrates considering multiple cage occupancy.
Journal of Chemical Physics. Roč. 160, č. 9 (2024), č. článku 094502. ISSN 0021-9606. E-ISSN 1089-7690
Institutional support: RVO:61388998
Keywords : gas hydrates * hydrogen * langmuir constant * nitrogen * multiple occupancy * thermodynamic model
OECD category: Thermodynamics
Impact factor: 4.4, year: 2022
Method of publishing: Open access
https://pubs.aip.org/aip/jcp/article/160/9/094502/3267953/Modification-of-the-van-der-Waals-and-Platteeuw

This study reviews available van der Waals- and Platteeuw-based hydrate models considering multiple occupancy of cavities. Small guest molecules, such as hydrogen and nitrogen, are known to occupy lattice cavities multiple times. This phenomenon has a significant impact on hydrate stability and thermodynamic properties of the hydrate phase. The objective of this work is to provide a comprehensive overview and required correlations for the implementation of a computationally sufficient cluster model that considers up to five guest molecules per cavity. Two methodologies for cluster size estimation are evaluated by existing nitrogen hydrate models showing accurate results for phase equilibria calculations. Furthermore, a preliminary hydrogen hydrate model is introduced and compared with the results of other theoretical studies, indicating that double occupancy of small sII cavities is improbable and four-molecule clusters are predominant in large sII cavities for pressures above 300 MPa. This work lays the foundation for further exploration and optimization of hydrate-based technologies for small guest molecules, e.g., storage and transportation, emphasizing their role in the future landscape of sustainable energy solutions.
Permanent Link: https://hdl.handle.net/11104/0353422