Biodiesel de gergelim (Sesamum indicum L.): um estudo de equilíbrio ternário

Abstract

The use of oil seeds as a source for biodiesel production constitutes an important raw material, and the encouragement of their production contributes to the agricultural development of the country. In this sense, there was a liquid-liquid equilibrium study of ternary systems: ethyl-glicerina- biodiesel ethanol and methyl-glycerin-methanol biodiesel to 313 K and 323 K. The miscibility limits or bimodal curve for these systems were obtained by the method determining the turbidity point. Data for the construction of mooring lines were determined by preparing mixtures of known concentrations of the three components in the two-phase forming region. These blends, after stirring were maintained at rest until the total separation of the phases, and then it was expected that the equilibrium was reached. After the samples of both phases were collected and analyzed on a balance of drying, where the alcohol was determined percentage of the glycerin rich phase, and the alcohol percentage in rich phase biodiesel. The other two biodiesel components and glycerin were determined using the equation found by the points of the binodal curve raffinate side, which is the phase rich in glycerine, and side extract, which is rich phase biodiesel, and thus created the lines bollard which called tie lines. This study evaluated the behavior of the bimodal curve via ethylic route and methyl at temperatures of 313 K and 323 K, and the study of phase equilibrium for biodiesel system sesame-glycerine-alcohol oil. The results showed that the effect of temperature is not influenced to the solubility of the systems studied, and the curves of the systems were well characterized, and the binodal curves sesame oil biodiesel system + ethanol + glycerin showed similarity to each other, however, there was a variation in the immiscibility region in relation to biodiesel system sesame oil + glycerine + methanol, making it smaller, an increase in the solubility between components. The model used UNIQUAC provided a good representation of experimental data, showing a standard of 1.47% and 0.90% deviations for biodiesel systems sesame oil + glycerine + ethanol and 0.49% and 0.21% for systems biodiesel sesame oil + glycerine + methanol, and there was also slight variation in solubility temperature variation.