Experimental Study and Correlation Models of the Density and Viscosity of 1-Hexene and 1-Heptene at Temperatures from (298 to 473) K and Pressures up to 245 MPa

Abstract

The density and viscosity of liquid 1-hexene and 1-heptene have been simultaneously measured over the temperature range from (298 to 473) K and pressures up to 245 MPa using the hydrostatic weighing and falling-body techniques, respectively. The combined expanded uncertainty of the density, pressure, temperature, and viscosity measurements at the 95 % confidence level with a coverage factor of k = 2 is estimated to be 0.15 % to 0.30 %, 0.05 %, 0.02 K, and 1.5 % to 2.0 % (depending on temperature and pressure ranges), respectively. The measured densities were used to develop a Tait-type equation of state for liquid 1-hexene and 1-heptene. Theoretically based Arrhenius–Andrade and Vogel–Tamman–Fulcher (VTF) type equations with pressure-dependent coefficients were used to represent the temperature and pressure dependences of the measured viscosities for liquid 1-hexene and 1-heptene. Also the friction theory (FT) viscosity model together with derived Tait-type equation of state (EOS) was used to accurately represent measured viscosity data. The measured values of the density and viscosity of 1-hexene and 1-heptene in the liquid phase were compared in detail with reported data and with the values calculated from correlations.