Waters contaminated with diesel/biodiesel and their blends can cause major environmental impacts, due to the presence of toxic and recalcitrant organic compounds, which invalidate the use of biological treatment processes. Evaluation of biodegradability of the blends B0, B25, B50, B75 and B100 (the numbers specify the mass percentage of biodiesel in the blend) indicated that the addition of biodiesel at concentrations above 50% increased biodegradation, reaching 60 and 80% for B50 and B75, respectively. When the Fenton process was used, removal of organic matter was greater than 80 % in all blends, except for B0, which showed maximum removal of 60%. Oxidation by Fenton was fitted with a pseudo-second order kinetic model in relation to the concentration of organic matter and resulted in increased biodegradation of up to 150%.
aerobic biodegradation; biodiesel; kinetics of oxidation; Fenton's reagent; advanced oxidation processes
