Monday, April 30, 2012
Napoleon Ballroom C-D, 3rd fl (Sheraton New Orleans)
Lipases (E.C. 3.1.1.3) are enzymes belonging to the hydrolyses class which act on ester bonds of acylglycerols. Normally, they are activated by a water-oil interface and exhibit quimioseletivity, regioseletivity and estereoseletivity. Besides catalyzing hydrolytic reactions, they also promote synthesis reactions in water-restricted environments such as esterification and transesterification reactions. Microbial Lipases have been studied for the production of biodiesel. The use of ultrasonic irradiation (UI) has also been showed to be very efficient in enzymatic catalysis. The continuous or intermittent irradiation of sound waves of high frequency favors the action of different enzymes in monophasic or biphasic systems. Thus, this work had the aim of studying the effect of UI on the ethylic biodiesel production using lipase from Thermomyces lanuginosus (TLL). The biodiesel production process was optimized by a factorial design 24 and response surface methodology. Temperature, oil:ethanol ratio, catalyst concentration and solvent were independent variables and the production of ethyl esters was the dependent variable. The optimum concentration for molar ratio, catalysts, temperature and solvent were, below 1:4. 5,5%, below 45ºC and 1:2 v/v, respectively. Evaluation of the influence of UI was carried out with oil:alcohol molar ratio of 1:3 and 1:4 and higher yields were obtained with molar ratio 1:4 and 10% UI. A positive effect of UI was seen on enzyme action, increasing reaction ratio from 84 to 99%. In conclusion, the UI proved to be an efficient method for the enzymatic ethylic biodiesel production.
Acknowledgments: FAPESP, CAPES and CNPq