‘Gel’ formation in carbon dioxide-semifluorinated alkane mixtures and phase equilibria of a carbon dioxide-perfluorinated alkane mixture

Vapor-Liquid Phase Coexistence of Alkane−Carbon Dioxide and Perfluoroalkane−Carbon Dioxide Mixtures

“…When also slightly decreasing the size parameter from σ ) 3.93 to 3.91 Å to reproduce more accurately the saturated liquid density for hexane (see Figure 2), the data point at 4.0 MPa pressure essentially coincides with the result using the SKS model. Figure 3b shows similar phase equilibrium results from simulation and experiment 45 for C 6 H 14 in CO 2 at 80°C. On the gas-phase branch in the moderate pressure range, the mole fraction of hexane in CO 2 from simulation is slightly smaller than experiment, 3-4% in comparison to the experimental data of about 5-6%.…”

“…This study may be considered an attempt to elucidate the degree to which the simple dispersion and geometric 45 Crosses are the experimental data of Yee et al 28 Open circles are simulation results obtained using the SKS model 34,35 for hexane. 45 Crosses are the experimental data of Yee et al 28 Open circles are simulation results obtained using a slight modification of the M-model, as presented in Table 1 45 Open circles are the results of simulation using the model presented in Table 1. Figure 5.…”

“…Symbols have the same meaning as in panel a. Figure 4a shows the phase diagram for perfluorohexane at 41.5°C from simulation, together with experimental data 45 at the same temperature and some experimental data at 40°C. 28 On the gas-phase branch of the coexistence curve, the solubility of perfluorohexane in CO 2 from simulation is close to experiment but slightly lower.…”

Phase behavior of carbon dioxide mixtures with n-alkanes and n-perfluoroalkanes

“…There is considerable controversy over the origin of the solvation power of CO 2 , in particular in relation to the origin of the exceptional solubility of fluorinated polymeric compounds. It is known than fluorinated compounds are more soluble in CO 2 than their hydrocarbon counterparts [3,4]. Iezzi et al [3] carried out experimental measurements of the phase behavior of CO 2 + n-hexane and CO 2 + n-perfluorohexane and showed that the differences in phase behavior between CO 2 + n-hexane and CO 2 + nperfluorohexane are consistent with the differences in purecomponent critical parameters.…”

“…It is known than fluorinated compounds are more soluble in CO 2 than their hydrocarbon counterparts [3,4]. Iezzi et al [3] carried out experimental measurements of the phase behavior of CO 2 + n-hexane and CO 2 + n-perfluorohexane and showed that the differences in phase behavior between CO 2 + n-hexane and CO 2 + nperfluorohexane are consistent with the differences in purecomponent critical parameters. Using dielectric constant measurements, Yee et al [4] found no evidence of special attractive interactions between CO 2 and perfluoroethane.…”