New experimental data on the solubility of CO 2 in water are reported in a wide temperature range (i.e., 274.14 up to 351.31 K). The experimental method is based on measurement of the bubble-point pressure of known water-CO 2 binaries at isothermal conditions using a variablevolume PVT cell. An extensive literature review has been conducted on the mutual solubilities of CO 2 -water systems and CO 2 hydrate-forming conditions. A critical evaluation of the literature data has been conducted to identify any inconsistencies in the reported data. The new experimental data generated in this work are also compared with the literature data, demonstrating the reliability of techniques used in this work. The Valderrama modification of the Patel-Teja equation of state combined with non-density-dependent mixing rules is used to model the fluid phases. The hydrate-forming conditions are modeled by the solid solution theory of van der Waals and Platteeuw with previously reported Kihara potential parameters. The fugacity of ice is calculated by correcting the saturation fugacity of water at the same temperature by using the Poynting correction. The new CO 2 solubility data generated in this work together with the most reliable literature data are used for tuning the binary interaction parameters between subcritical CO 2 and water. The previously reported binary interaction parameters for CO 2 and water are used for the supercritical region. The predicted water content and the hydrate dissociation conditions are compared with the experimental data. The model results are in good agreement with independent experimental data, demonstrating reliability of the techniques and model presented in this work.

Isothermal vapor-liquid equilibrium data for the Difluoromethane (R32) + Propane binary system are presented at 278.10, 294.83, 303.23, 313.26 and 343.26 K and pressures up to 5.4 MPa. The experimental method is the static-analytic type. It takes advantage of mobile pneumatic capillary samplers (Rolsi™, Armines' patent) developed in our laboratory. At a fixed temperature the azeotrope vapor pressure is larger then those of the pure component. The particularity of R32-Propane azeotropic binary system is to present in two critical point over the critical temperature if the azeotrope. This particular behavior has been proved and even shown visually by means of two supplementary experiments with equipment based on the static-synthetic method involving a variable volume cell. Data along the five isotherms have been represented with the Soave-Redlich-Kwong (SRK) equation of state and MHV1 mixing rules involving the NRTL model. We have calculated the location of the azeotrope using the equality of Equation of State attractive parameter between the two phases.

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Isothermal vapour-liquid equilibrium data for the difluoromethane (R32)-1,1,1,2,3,3,3-Heptafluoropropane (R227ea) binary system are presented at 283.20, 303.21, 323.21 and 343.38 K and pressures up to 4.5 MPa. The experimental method, used for this work, is of the static-analytic type. It takes advantage of mobile pneumatic capillary samplers (Rolsi TM , Armines' patent) developed in our laboratory. The four P, x, y isothermal data have been represented with the Soave-Redlich-Kwong (SRK) equation of state and the MHV1 rules involving the NRTL model.