Modeling of density and calculations of derived volumetric properties for n-hexane, toluene and dichloromethane at pressures 0.1-60 MPa and temperatures 288.15-413.15 K

Abstract

Densities data of n-hexane, toluene and dichloromethane at temperatures 288.15-413.15 K and at pressures 0.1-60 MPa, determined in our previous work, were fitted to the modified Tait equation of state. The fitted temperature-pressure dependent density data were used to calculate the derived properties: the isothermal compressibility, the isobaric thermal expansivity, the difference between specific heat capacity at constant pressure and at constant volume and the internal pressure, 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 the literature data. [Projekat Ministarstva nauke Republike Srbije, br. 172063]

Thermodynamic and Transport Properties of Biomass-Derived Furfural, Furfuryl Alcohol and Their Mixtures

“…The change of density as a response to pressure change is described by the isothermal compressibility, κ T : [34]…”

“…The influence of temperature on density, i.e., the change of density when temperature is changed under constant pressure, is described by the isobaric thermal expansivity, α p : [34]…”

“…The thermal pressure coefficient, γ, which represents the ratio between κ T and α p , can be calculated as follows: [34]…”

“…The internal pressure, p int , which gives insight into intermolecular interaction of the sample can be determined using Equation ( 12): [34]…”

“…where U stands for an internal energy and V is volume of the sample. Another important thermodynamic property is the difference between the specific heat capacity at constant pressure, c p , and the specific heat capacity at constant volume, c v : [34]…”