Produção de biodiesel de sebo bovino assistida por banho de ultrassom utilizando o planejamento experimental

Abstract

One of the most researched areas regarding the study of chemistry relates to the production of fuels that are environmental-friendly and have a larger economic feasibility. In this context, the biodiesel production has gained prominence and the bovine tallow is a promising raw material due to its great availability in slaughterhouses and because it presents a low production cost. On a large scale, the biodiesel uses the vegetable oil transesterification process to employ homogeneous chemical catalysts that although are more feasible than other vegetable oils viscosity reduction method, still imply a high energy cost and a hard byproduct extract on the process. Thus, the aim of this paper was to verify potentiality of the bovine tallow for the biodiesel production, through the transesterification assisted by ultrasound, and besides to study the influence of variables using the Experimental Design. The biodiesel synthesis was done through the transesterification by basic heterogeneous catalysis. The reaction occurred using an alcohol (methanol) in the presence of a basic catalyst (KOH), at 45°C (113º F) for 30 minutes. The reaction using ultrasound was similar to the conventional method, differing only in the temperature change of 65°C (149°F). Applying a different technique on which was used the ultrasound bath to heat the reagents, percentages close to the conventional method were obtained, of 87.00%. The experiment with the highest yield, 98.76%, was carried out with 0.8g of KOH, 13 mL of methanol and 40 min of heating. The Pareto Diagram did not present factors and interaction of significant factors. The bovine tallow recycling not only removed an unwanted compound from the environment, but also permits the generation of an alternative energy source which is renewable and less polluting.