Solubility and Liquid Density of Binary Mixtures of n‑Hexane or 1‑Hexanol with Krypton, Sulfur Hexafluoride, or R143a

Within the present study, the solubility, phase behavior, and liquid density of binary systems consisting of n-hexane (C6H14) or 1-hexanol (C6H14O) and krypton (Kr), sulfur hexafluoride (SF6), or the refrigerant 1,1,1-trifluoroethane (R143a) are investigated at temperatures between 303 and 348 K and pressures up to 14 MPa. For this, the isochoric-saturation method featuring in-line density measurements of the saturated liquid phase is applied in combination with Raman spectroscopy. The latter is calibrated for the systems comprising SF6 and R143a with the experimentally measured solubility data to allow for the determination of the liquid-phase composition of these binary mixtures on other setups solely by the evaluation of Raman spectra. This is performed in this study on a second setup where the Raman spectra obtained especially in the SF6- and R143-rich regimes complement the characterization of the phase behavior. The solubility in C6H14O was found to be distinctly lower than in C6H14 for all gases. Furthermore, a liquid–liquid phase separation was observed for C6H14O/SF6 and C6H14O/R143a at nearly all investigated temperatures. These and further results are discussed in connection with the molecular properties of the mixture components.