Densities of the Binary Systems n-Hexane + n-Decane and n-Hexane + n-Hexadecane Up to 60 MPa and 463 K

Abstract

The densities of the binary systems n-hexane + n-decane and n-hexane + n-hexadecane have been measured up to 60 MPa using a vibrating tube densimeter. The measurements covered the whole composition range; for the first system they were performed from (278.15 to 463.15) K, while for the latter they were performed from (298.15 to 463.15) K because n-hexadecane is a solid at 278.15 K. The densities were correlated for every composition as a function of temperature and pressure using a modified Tammann–Tait equation with standard deviations lower than 8·10–4 g·cm–3. Isothermal compressibility values were calculated from the experimental density data. Moreover, the excess volumes were found to be negative for all of the studied mixtures, with absolute values less than or equal to 3.25 cm3·mol–1 for the n-hexane + n-decane system and 7.65 cm3·mol–1 for the n-hexane + n-hexadecane system. Various equations of state were used to model the measured density data.