Density of biofuel mixtures (Dibutyl ether + Heptane) at temperatures from (298.15–393.15) K and at pressures up to 140 MPa: Experimental data and PC-SAFT modeling

Abstract Density has been reported to binary mixtures (552 points) of dibutyl ether (DBE) + heptane in the composition range (4 compositions; 0.325 ≤ dibutyl ether mole fraction x ≤ 0.85), between 298.15,393.15 K, and for 23 pressures ranging from 0.1 MPa to 140 MPa. These experimental measurements were carried out using an apparatus, comprising a vibrating tube densimeter Anton Paar, calibrated with an uncertainty of about 0.7 kg· m-3. The volumetric behavior and excess molar volume of DBE + heptane were modeled using PC-SAFT equation. The PC-SAFT parameters of DBE and heptane were optimized using experimental density data at atmospheric pressure. The density of the mixture was reasonably well predicted, with a mean relative difference between 0.0009% and 1.99%. Whereas the excess molar volume not satisfactorily predicted. A Tait equation was used to adjust the experimental density data. In addition, from this equation the isobaric thermal expansion and the isothermal compressibility were derived.