Equilibrio de fases do sistema ternário biodiesel de Mamona-Etanol-Glicerina utilizando a viscosidade como parâmetro para a determinação da composição das fases

Abstract

Biodiesel is a fuel derived from renewable sources as vegetable oils and animal fat and can be obtained from transesterification reaction. This process involves reacting vegetable oil with alcohol in the presence of a catalyst, followed by a purification step. The focus of this study was to determine the binodal curve and the tie lines for ternary mixtures of biodiesel from castor oil-ethanol-glycerin. The liquid-liquid equilibrium data will assist the purifying of the final product from transesterification reaction. The binodal curves were determined at 30 °C, 45 °C and 60 °C, and the tie lines were obtained for the system at 30 °C. The parameters used to determine the tie lines were the viscosity and density, instead of gas chromatography, traditionally used to determine the composition of the phases. The tie lines to the system of castor oil biodiesel - ethanol - glycerin at 30 °C obtained from the viscosity of the rich phase in biodiesel and the rich phase in glycerin, showed satisfactory results, providing data of phases composition. However, when using the density, the results were inconsistent with the observed data in the literature.