Measurements of Pressure-Volume-Temperature Properties of 1,1,2,2-Tetrafluoroethane

The experimental vapor pressures and pressure-volume-temperature (PVT) properties of an important alternative refrigerant, 1,1,2,2-tetrafluoroethane (HFC-134), have been measured by means of the constant-volume method coupled with expansion procedures in an extensive range of temperatures, pressures, and densities. One hundred seventeen PVT property data were measured along 14 isochores in a range of temperatures from 318 to 443 K, pressures from 0.4 to 9.8 MPa, and densities from 18 to 1103 kg/m³. Fifty-one vapor pressures were also measured at temperatures from 303 K to the critical temperature. The uncertainties of temperature and pressure measurements are less than ±10 mK and ±3.2 kPa, respectively, while the uncertainty of density values is less than ±0.11%. The purity of the sample used is 99.98 wt %. Saturated liquid/vapor densities are expected to be accurate within ±0.4% including the uncertainties due to the extrapolation procedure.