Modeling of density and calculations of derived volumetric properties at pressures 0.1-60 MPa and temperatures 288.15-413.15 K

Abstract

Density data of n-hexane, toluene and dichloromethane at temperatures 288.15-413.15 K and at pressures 0.1-60 MPa were fitted to the modified Tait equation of state. The appropriate equations for calculating the isothermal compressibility, the isobaric thermal expansivity, the difference between specific heat capacity at constant pressure and at constant volume, and the internal pressure are presented in this work and also the values of the mentioned derived properties are given over the entire temperature and pressure intervals specified above. In order to assess the proposed  modeling procedure, a comparison of the obtained values for the isothermal compressibility and the isobaric thermal expansivity with the corresponding literature data were performed. The average absolute percentage deviations for isothermal compressibility were: for n-hexane 2.01-3.64%, for toluene 0.64-2.48% and for dichloromethane 1.81-3.20%; for the isobaric thermal expansivity: for n-hexane 1.31-4.17%, for toluene 0.71-2.45% and for dichloromethane 1.16-1.61%. By comparing the obtained deviations values with those found in the literature it can be concluded that the presented results agree good with literature data.