Thermodynamic Properties of R‑227ea, R‑365mfc, R‑115, and R-13I1

• Published in: Journal of chemical and engineering data Vol. 60; no. 12; pp. 3745 - 3758
• Main Authors: Lemmon, Eric W, Span, Roland
• Format: Journal Article
• Language: English
• Published: American Chemical Society 10-12-2015
• ISSN: 0021-9568; 1520-5134
• DOI: 10.1021/acs.jced.5b00684

Equations of state are presented for the refrigerants 1,1,1,2,3,3,3-heptafluoropropane (R-227ea) and 1,1,1,3,3-pentafluorobutane (R-365mfc). For R-227ea, the uncertainties in densities are 0.05 % in the liquid region up to 360 K, 0.3 % in the vapor phase, and 0.5 % in the supercritical region. For vapor pressures, the uncertainties are 0.1 % above 270 K and 0.4 % between 240 K and 270 K (with the higher value at the lower temperature). The uncertainty in heat capacities is 1 % (with increasing uncertainties in the critical region and at high temperatures). For sound speeds, the uncertainties are 0.05 % in the vapor phase up to pressures of 0.5 MPa and 0.03 % in the liquid phase between 280 K and 420 K. For R-365mfc, the uncertainties in densities of the equation of state range from 0.1 % in the liquid to 1 % near the critical point, and the uncertainty in the speeds of sound is 0.05 %. The uncertainty in heat capacities is 2 %, and the uncertainty in vapor pressures is 0.25 % at temperatures between 280 K and 360 K. In the critical region, the uncertainties are higher for all properties. Equations of state for trifluoroiodomethane (R-13I1) and chloropentafluoroethane (R-115) are also given in an appendix for applications where systems using these banned substances are being upgraded or replaced with modern refrigerants, and properties of the old working fluids are needed in the design of the new system.