This project aims to perform the experimental analysis and the thermodynamic modeling of the vapor-liquid phase behavior of ternary systems involving water and components present in biodiesel, ethanol and glycerol, at atmospheric pressure. The experimental process will be performed in an equipment composed of the modified Othmer ebuliometer, ultrathermostatic baths, temperature and pressure sensors, vacuum pump and digital manometer. The ebuliometer will be coated with glass wool to minimize heat losses and will have an adaptation to the counting of the condensed drops of the vapor phase. The analyzes (compositions of the liquid and vapor phases) will be done through the refractive index and density. Calibration curves (refractive index and density versus composition) will be made previously. In the thermodynamic modeling, the gamma-phi (g-f) approach will be used and the activity coefficient, g, will be obtained from models of excess Gibbs free energy such as the NRTL (Non-Random Two-Liquids) model and the coefficient of fugacity, f, will be determined from the Peng-Robinson equation with van der Waals mixing rules. Results will be presented in terms of the deviations of the bubble temperature and compositions in the vapor phase (Bubble T), as well as the respective ternary diagrams (triangular diagrams).
News published in Agência FAPESP Newsletter about the scholarship: