Experimental and thermodynamic modeling study on (vapor + liquid) equilibria and physical properties of ternary systems (methane + n-decane + n-tetradecane)

The vapor–liquid equilibrium (VLE) data of ternary systems (methane + n-decane + n-tetradecane) at ambient temperature and various pressures, 1–8 MPa, have been measured using a designed pressure–volume–temperature (PVT) apparatus. The phase compositions and saturated liquid phase properties, density and viscosity, have been measured for each pressure. The densities of three different (n-decane + n-tetradecane) binary mixtures have also been measured at ambient temperature over a wide range of pressures (1–10 MPa). The generated experimental data have been correlated with two cubic equations of state (EoS), Peng–Robinson (PR) and Soave–Redlich–Kwong (SRK). The binary interaction parameters and the volume shift values from the experimental information on the binary pairs, (methane + n-decane) and (methane + n-tetradecane), have been used to predict the VLE data of ternary system (methane + n-decane + n-tetradecane). Both equations of state have been found to be capable of describing the phase equilibria of binary pairs as well as ternary systems over the range of studied conditions.