PvT Properties, Saturation Pressures, Saturated Densities, and Critical Parameters of Trifluoroiodomethane (CF₃I; R-13I1)

Abstract

Measurements of PvT properties, saturated pressures, saturated densities, and critical parameters were carried out for R-13I1 (trifluoroiodomethane; CF 3 I). Forty-seven PvT property data in the one-phase region along seven isochores for R-13I1 were obtained in the temperatures between 310 and 405 K, pressures up to 6392 kPa, and densities between 48 and 1784 kg•m −3 using the isochoric method. Thirty-seven saturation pressure data for R-13I1 were obtained in the temperatures between 240 K and the critical temperature and pressures between 58 kPa and the critical pressure. Twenty-six saturated density data for R-13I1 were obtained by the observation of meniscus disappearance and the inflection points of the isochore in the densities between 48 and 1784 kg•m −3 . On the basis of these measurements, the critical temperature, critical density (critical molar volume), and critical pressure of R-13I1 were determined as T c = 396.495 ± 0.010 K (with a coverage factor, k = 2), ρ c = 865 ± 5 kg•m −3 (v c = 226.5 ± 1.3 cm 3 •mol −1 ) (bracketed interval), and P c = 3971 ± 3 kPa (with a coverage factor, k = 2), respectively. Moreover, a correlation for the saturation pressure and correlations for the vapor liquid coexistence curve were established by optimization techniques.

PvT Properties and Thermodynamic Property Correlations for the Low Global Warming Potential Hydrofluoroolefin Refrigerant R-1132a (1,1-Difluoroethene)

“…These data together with the critical parameters defined within this work were used to optimize a new coexistence curve [ 24 ]. A simplified five-term Guggenheim’s equation [ 25 ] was chosen to represent the two saturated curves separately and is given in Eq.…”

“…The errors associated with each method are as follows: the meniscus method has expanded uncertainties (k = 2) for temperature of U T = 10 mK and U ρ for densities which are provided in Table 8 with the experimental data; the PvT inflection points have expanded uncertainties (k = 2) for temperature, pressure and density of U T = 30 mK, U P = 2 kPa and U ρ = 0.0015•ρ kg•m −3 for App-HRT and U T = 30 mK, U P = 2 kPa and U ρ = 0.002•ρ kg•m −3 for App-WRT. These data together with the critical parameters defined within this work were used to optimize a new coexistence curve [24]. A simplified five-term Guggenheim's equation [25] was chosen to represent the two saturated curves separately and is given in Eq.…”