抄録
We report a theoretical study to predict the phase-equilibrium properties of ozone-containing clathrate hydrates based on the statistical thermodynamics model developed by van der Waals and Platteeuw. The Patel-Teja-Valderrama equation of state is employed for an accurate estimation of the fugacities in the gas phase. An infinite set of σ-ε Kihara parameters for ozone were determined, reproducing the experimental phase equilibrium pressure-temperature data of the (0_3 + 0_2 + C0_2) clathrate hydrate. A unique parameter pair was chosen based on the experimental ozone storage capacity data for the (0_3 + 0_2 + CCl_4) hydrate. We determined the three parameters of the Kihara intermolecular potential for ozone as α = 6.815 × 10^<-2> nm, σ = 2.9909 x 10^<-1> nm, and ε × k_B^<-1> = 184.00 K. The prediction with the developed model showed good agreement with the experimental phase equilibrium data within ±2% of the average deviation of the pressure. The Kihara parameters of ozone showed that ozone is slightly better suitability for the structure I hydrate than C0_2, which was used as a help guest. Our model suggests the possibility of increasing the ozone storage capacity of clathrate hydrates (〜7% on a mass basis).
