Thermodynamic properties of HFO-1234yf (2,3,3,3-tetrafluoropropene)

Measurements of the thermodynamic properties of HFO-1234yf were conducted. The critical temperature TC, critical density ρC, and critical pressure PC, were measured by the visual observation of the meniscus disappearance, and were determined to be 367.85 ± 0.01 K, 478 ± 3 kg/m3, and 3382 ± 3 kPa, respectively. Vapor pressures were measured by a batch-type calorimeter with a metal-bellows in the temperature range from 310 K to 360 K and correlated by the Wagner-type equation. Surface tensions were measured by the differential capillary-rise method in the temperature range from 273 K to 340 K and correlated by the van der-Waals type equation. The acentric factor was determined to be 0.280 with the vapor pressure correlation. Based on the critical parameters and acentric factor, saturated vapor and liquid densities were estimated by the Peng–Robinson equation and the Hankinson–Thomson equation, respectively. The heat of vaporization was also calculated from the Clausius–Clapeyron equation.