Abstract

A modification of the original van der Waals and Platteuw (vdWP) theory that accounts for free-energy contributions due to the vibrational and librational movement of water molecules in the hydrate lattice is presented. The modified theory is labeled vdWP-FL. In our previous work, we had presented a method to compute these contributions to the partition function. This was successfully applied to simulated phase equilibria of various gas hydrates. In this work, we apply the vdWP-FL theory to experimental data of gas hydrate phase equilibria and recompute the guest–water potentials. The empty hydrate reference properties are directly computed from molecular simulations. In this implementation of the vdWP-FL theory, only one parameter per guest molecule per cavity type is regressed from the experimental data on gas hydrates. The gas hydrates chosen for this study are methane, ethane, carbon dioxide, propane, iso-butane, and the hydrates formed by their binary mixtures. The vdWP-FL theory gives accurate predictions of the dissociation temperatures and pressures of the above gas hydrates and their mixtures. In addition, it also predicts the hydrate cage occupancy accurately.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.