Three-phase liquid-liquid-vapor equilibria in the methane + ethane + n-hexane and methane + ethane + n-heptane systems

The three-phase L/sub 1/-L/sub 2/-V equilibria behaviour of the ternary systems methane + ethane + n-hexane and methane + ethane + n-heptane is studied. Also presented are the results for the binary system methane + n-heptane. The compositions and molar volumes of the liquid phases are reported as functions of temperature and pressure within the immiscibility regions. The two ternary systems have constituent binaries that exhibit L/sub 1/-L/sub 2/-V immiscibility (methane + n-hexane and methane + n-heptane, respectively). The addition of the third component, ethane, promotes three-phase behaviour in a region extending upward in temperature.