Measurement and thermodynamic modeling of carbon dioxide hydrate formation conditions using dry water through hydrophobic nano silica

摘要

Dry water is accounted for as an effective medium for gas storage in a clathrate hydrated form. We used the van der Waals-Platteeuw framework for correlation of the experimental CO2 hydrate formation conditions in the presence of dry water through a reversed micellar approach. Activity of water in a reversed micelle presented an effect on the thermodynamic characteristics of a dry water system. The binary interaction parameters of the UNIQUAC model was adjusted using the CO2 - H2O hydrate equilibrium formation conditions data. Due to the hydrophobic nature of the nanoparticles, the hydration forces contributed the predominant term at the water chemical potential function using a dry water medium. The results showed that dry water presented a thermodynamic promoter effect. Therefore, applying a water-in-air microemulsion model, a good agreement of the calculated values with the experimental data was demonstrated using the two adjustable parameters of the hydration force term.