Measurement and Prediction of Densities of Vegetable Oils at Pressures up to 45 MPa

This work addresses the measurement and modeling of the densities of seven vegetable oils (soybean, rapeseed, castor, palm, sunflower, Aleurites moluccana, and Jatropha curcas oils) at temperatures from (283.15 to 363.15) K and pressures from (0.1 to 45) MPa. The data measured here was correlated using the modified Tait-Tammann equation, and the data was used to evaluate the predictive abilities of the Halvorsen model, the fragment-based approach, and the revised GCVOL group contribution method. The results show that the models studied described well the experimental data, presenting not only stable deviations over the temperature range but also overall average relative deviations (OARD) of only (1.2, 0.34, and 1.1) %, respectively. An extension of the models here studied to high pressure is proposed. The models of Halvorsen, Zong, and revised GCVOL provide very good predictions of high-pressure densities with OARDs of (0.75, 1.04, and 0.41) %, respectively, with the deviations presenting just a slightly pressure-dependent with maximum deviations of less than 2.0 %