Lipase-Catalyzed Biodiesel Production from Grease Trap

The production of biodiesel from oily waste has been reported as a promising alternative for the use of biomass in energy. However, the high content of free fatty acids makes traditional chemical catalysis processes difficult. This work aimed to evaluate the enzymatic production of biodiesel from oily residues derived from sanitation and its optimization for large-scale applications. We evaluated the production of biodiesel from a University Restaurant grease trap using lipases as catalysts (Candida antarctica, Thermomyces lanuginosa, Mucor miehei). The experiments were performed by using a factorial design of type 3(2) to evaluate the best conditions of temperature (30, 40 and 50 degrees C) and enzyme concentration (5, 7.5 and 10% w/w) for each different enzyme. When the enzyme obtained from C. antarctica was used, the high yield was obtained in all studied conditions and none of the variables was statistically significant. As for the enzymes from the T. lanuginosa and the M. miehei significant effect of the temperature was reported, the higher yield was obtained with lower temperatures (30-40 degrees C). The concentration of enzymes only was statistically significant with enzyme from M. miehei, which had better yield with 10% w/w fat. Still, the lowest yields of biodiesel were obtained when using the enzyme from M. miehei. The enzymatic production of biodiesel from oily residues can be an interesting strategy for reducing production costs and an alternative for the sustainable treatment of oily residues from sanitation.