PVTx Properties of the R245fa/R1234ze(E) for Low-Temperature Organic Rankine Cycle

The gaseous PVTx properties of 1,1,1,3,3- pentafluoropropane (R245fa) + trans-1,3,3,3-tetrafluoropropene (R1234ze(E)) mixtures were measured at temperatures from 300.5 to 335.5 K and corresponding pressures from 144.1 to 598.8 kPa, and the composition of R245fa from 0.60 to 0.85 mass fraction used the Burnett isothermal expansion method. The uncertainties of the experimental device was estimated to be +/- 8.1 mK for temperature, +/- 1.7 kPa for pressure and +/- 0.003 for mass fraction. The experimental results were corrected using the virial equation of state (EOS) and the second and third virial coefficients of the virial EOS were fitted. Good agreement in the pressures obtained by virial EOS with the experimental pressures was found with relative errors within +/- 0.8%.