PρT measurements and modelling of (n-decane + m-xylene) mixtures from 293.15 K to 363.15 K at pressures up to 60 MPa

Highlights: • High pressure density data of n-decane and m-xylene mixtures were reported. • The sPC-SAFT and CPA EoSs were applied to predict the densities of n-decane and m-xylene and their mixtures. • The effects of pressure and temperature on the excess molar volume were discussed. -- Abstract: In this work, the experimental measurements for liquid densities of n-decane and m-xylene binary mixtures were performed over the entire composition range with a high-pressure vibrating-tube densimeter. The range of temperatures for the present measurements was from 293.15 K to 363.15 K and the pressures were up to 60 MPa. The combined expanded uncertainty of the density measurements is estimated to be 0.001ρ with 0.95 confidence. Experimental density values were correlated by the modified Tammann-Tait equation. The simplified Perturbed Associating Fluid Theory (sPC-SAFT) and Cubic Plus Associated (CPA) equations of state (EoS) were applied to predict the densities of n-decane and m-xylene and their mixtures. Reasonably results were observed between the experimental data and calculated results for the two equations, and the deviation is less than 0.48% and 0.89% with sPC-SAFT and CPA EoS, respectively. In addition, excess molar volumes were determined from the experimental density data as well as from sPC-SAFT and CPA models. The effects of pressure and temperature on the excess molar volume were also discussed.