Thermodynamic properties for 1-hexene – Measurements and Modeling

Abstract

A fundamental equation of state is presented for 1-hexene. It is explicit in the reduced Helmholtz energy and depends on the independent variables temperature and density. It is valid in the fluid region at temperatures from the triple–point temperature Ttr = 133.39 K to Tmax = 535 K with a maximum pressure of pmax = 245 MPa. All thermodynamic properties can be determined from the Helmholtz energy and its derivatives with respect to temperature and density. The equation of state is validated by comparison with experimental data, along with an assessment of correct physical and extrapolation behavior. The available data base is further extended by measurements of the homogeneous density with a vibrating-tube densimeter in the temperature range from 300K to 362K and pressures of up to 92 MPa. Speed of sound measurements are conducted with two independent apparatuses at temperatures of 215 K to 500 K and pressures of up to 151 MPa, applying the double-path-length pulse-echo technique.