resumo
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 %.
palavras-chave
SUPERCRITICAL-FLUID EXTRACTION; FATTY-ACID METHYL; ETHYL-ESTERS; BIODIESEL; COMBUSTION; EMISSIONS; EQUATION; TEMPERATURE; VISCOSITIES; SOLUBILITY
categoria
Thermodynamics; Chemistry; Engineering
autores
Freitas, SVD; Silva, FAE; Pastoriza-Gallego, MJ; Pineiro, MM; Lima, AS; Coutinho, JAP
nossos autores
Grupos
G4 - Materiais Renováveis e Economia Circular
G5 - Materiais Biomiméticos, Biológicos e Vivos
agradecimentos
S.F. acknowledges a Ph.D. Grant from Fundacao para a Ciencia e a Tecnologia through his Ph.D. grant (SFRH/BD/51476/2011), Fundacao Oriente, and also financial support from the University of Aveiro. CICECO is being funded by Fundacao para a Ciencia e a Tecnologia through Pest-C/CTM/LA0011/2013.