Isothermal (vapour + liquid) equilibrium measurements and correlation for the {n-butane (R600) + 1,1,1,3,3-pentafluoropropane (R245fa)} system at temperatures from (303.150 to 373.150) K

• VLE data for (R600 + R245fa) system at temperatures ranging from 303.15 to 373.15 K were measured.
• The experiments were based on the static–analytic method.
• Correlation of VLE data was made using PR–HV–NRTL model.

The isothermal VLE for the {n-butane (R600) + 1,1,1,3,3-pentafluoropropane (R245fa)} system was measured at five temperatures from (303.150 to 373.150) K based on the static-analytical method. The experimental values were correlated by the Peng–Robison equation of state with the Huron–Vidal mixing rule involving the non-random two-liquid (NRTL) activity coefficient model. The results show that the experimental values are in good agreement with the calculated value. The maximum average absolute relative deviation of pressure and vapour phase mole fraction are 0.35%, 0.0047, respectively. Obviously azeotropic behaviour can be observed for the binary system.