Produção de biodiesel por transesterificação utilizando banho ultrassônico

Abstract

The most widely used method for producing biodiesel is the transesterification reaction, in which oil and excess alcohol are mixed with a catalyst. However, because the reactants are partially miscible it is necessary to maintain the reaction under mechanical agitation and heating for a certain time. Therefore, this is a method that consumes a lot of energy and for this, some alternatives are being increasingly researched, such as the use of ultrasound, which promotes cavitations in the reaction medium, and also the use of co-solvent, both increase the contact between the phases. In this way this work aims to produce biodiesel by transesterification using ultrassonic bath. To obtain the samples were used etanol and soybean oil, in the molar ratio of 10,2:1, with potassium hydroxide catalyst. In the experiments were varied the temperatures, reaction times and the use of biodiesel as co-solvent. After the analysis of density and conversion of the reactions, it was possible to notice that the application of ultrassonic bath is a promising technology to promote decrease in the reaction time and consequently, to reduce energy expenditure.