The study of B100 biodiesel oxidation stability, and its conservation, is extremely important to control its quality, especially regarding storage. Many spices have shown antioxidant effect and are the targets of study. Knowing the oxidation process in greater detail allows a reliable storage period to be stipulated for the biodiesel without its degradation until the time of use. Results have shown that according to the accelerated stove method, the optimal mixture, composed of 100% of oregano extract, can confer a 535-day shelf life to biodiesel without evident oxidation. According to the results obtained by the Rancimat method, the ideal mixture consists of 100% rosemary, resulting in 483 days of storage. The application of the process variable showed that the accelerated stove method was more suitable to determine oxidative stability of biodiesel. 1. Introduction For many decades, fossil fuels have supplied the energy demand but it is known that these fuels release carbon dioxide gas, the main cause of the greenhouse effect, and sulphur oxides, associated to the acid rain phenomenon. These negative contributions to the environment have triggered the search for sources of clean and renewable energy and the use of biofuels has presented a viable alternative to solve these problems [1]. The use of biomass, represented mainly by vegetable oils, is a good strategy both in economic terms and environmental preservation [2]. In this context, biodiesel can be highlighted. It is defined as mono-alkyl ester from fatty acids produced by the reaction of vegetable oils or animal fat with alcohol, usually methanol, in the presence of a catalyst, normally a strong base such as sodium or potassium hydroxide, or even an acid, and this reaction is known as transesterification [3, 4]. The high compatibility of biodiesel with petroleum diesel characterizes it as an good alternative capable of supplying most of the existing diesel fleet without great adaptations. It is also biodegradable and renewable, has a lubricant capacity in the pure form, and is competitive with diesel in terms of fuel properties [1]. However, unlike fossil fuels that are relatively inert and maintain their essential characteristics with little alteration during storage, biodiesel degrades with time and can be altered due to the action of air, light, temperature, and moisture. Contact with contaminants, both inorganic and microbial nature, can also tend to introduce variations in product quality, and oxidation resulting from its exposure to atmospheric air is one of the main degradation problems to
References
[1]
G. Knothe, “Some aspects of biodiesel oxidative stability,” Fuel Processing Technology, vol. 88, no. 7, pp. 669–677, 2007.
[2]
L. P. Ramos, K. T. Kucek, A. K. Domingos, and H. M. Wilhelm, “Um projeto de sustentabilidade econ？mica e sócio-ambiental para o Brasil,” Revista Biotecnologia Ciência & Desenvolvimento, pp. 28–37, 2003.
[3]
R. A. Ferrari, V. S. Oliveira, and A. Escabio, “Biodiesel de soja—taxa de convers？o em ésteres etílicos, caracteriza？？o físico-química e consumo em gerador de energia,” Química Nova, vol. 28, pp. 9–23, 2005.
[4]
L. C. Meher, D. V. Sagar, and S. N. Naik, “Technical aspects of biodiesel production by transesterification—a review,” Renewable and Sustainable Energy Reviews, vol. 10, no. 3, pp. 248–268, 2006.
[5]
R. A. Ferrari and W. L. De Souza, “Evaluation of oxidation stability of sunflower oil biodiesel with antioxidants,” Quimica Nova, vol. 32, no. 1, pp. 106–111, 2009.
[6]
V. C. Ramalho and N. Jorge, “Antioxidants used in oils, fats and fatty foods,” Quimica Nova, vol. 29, no. 4, pp. 755–760, 2006.
[7]
R. L. McCormick, M. Ratcliff, L. Moens, and R. Lawrence, “Several factors affecting the stability of biodiesel in standard accelerated tests,” Fuel Processing Technology, vol. 88, no. 7, pp. 651–657, 2007.
[8]
J. Pokorny, “Are natural antioxidants better- and safer- than synthetic antioxidants?” European Journal of Lipid Science and Technology, vol. 109, pp. 629–642, 2007.
[9]
R. Amarowicz and R. B. Pegg, “Legumes as a source of natural antioxidants,” European Journal of Lipid Science and Technology, vol. 110, no. 10, pp. 865–878, 2008.
[10]
H. L. Madsen and G. Bertelsen, “Spices as antioxidants,” Trends in Food Science and Technology, vol. 6, no. 8, pp. 271–277, 1995.
[11]
N. Nakatani and R. Inatani, “Two antioxidative diterpenes from rosemary(Rosrnarinus officinalis L.) and a revised structure for rosmanol,” Agricultural and Biological Chemistry, vol. 48, pp. 2081–2085, 1984.
[12]
H. Kikuzaki and N. Nakatani, “Structure of a new antioxidative phenolic acid from oregano (Origanum vulgare L.),” Agricultural and Biological Chemistry, vol. 53, pp. 519–524, 1989.
[13]
N. Bragagnolo and L. R. B. Mariutti, “Revis？o: antioxidantes naturais da família lamiaceae. Aplica？？o em Produtos Alimentícios,” Brazilian Journal of Food Technology, vol. 10, pp. 96–103, 2007.
[14]
D. R. Thompson, “Designing mixture experiments—a review,” Transactions of the American Society of Agricultural Engineers, vol. 24, no. 4, pp. 1077–1086, 1981.
[15]
D. M. Steinberg and W. G. Hunter, “Experimental design: review and comment,” Technometrics, vol. 26, no. 2, pp. 71–130, 1984.
[16]
P. K. Soares, R. E. Bruns, and I. S. Scarminio, “Statistical mixture design investigation of fractionated and total extracts from Erythrina speciosaAndrews leaves,” Journal of Separation Science, vol. 32, pp. 644–652, 2009.
[17]
J. Marchi, J. C. Bressiani, A. H. A. Bressiani, and R. E. Bruns, “Mixture design and response surface analysis of densification of silicon carbide ceramics with (SiO2-Dy2O3-Al2O3) additives,” International Journal of Applied Ceramic Technology, vol. 7, no. 4, pp. 493–501, 2010.
[18]
J. A. Cornell and J. C. Deng, “Combining process variables and ingredient components in mixing experiments,” Journal of Food Science, vol. 47, pp. 836–843, 1982.
[19]
D. C. Montgomery, “Experimental design for product and process design and development,” The Statistician, vol. 44, part 2, pp. 159–177, 1999.
[20]
M. C. Gacula, Design and Analysis of Sensory Optimization, Food & Nutrition Press, Trumbull, Conn, USA, 1993.
[21]
D. Borsato, C. L. B. Guedes, I. Moreira, J. P. Pinto, G. H. Dias, and K. R. Spacino, “Conditions optimization for obtaining biodiesel from soybean oil using the mixture experimental design,” Semina, vol. 31, pp. 3–13, 2010.
[22]
R. F. Almeida-Doria and M.A.B.. Regitano-D'Arce, “Antioxidant activity of rosemary and oregano ethanol extracts in soybean oil under thermal oxidation,” Ciência E Tecnologia de Alimentos, vol. 20, pp. 197–203, 2000.
[23]
American Oil Chemist’s Society (A.O.C.S.), Official Methods and Recommended Practices of the American Oil Chemists Society, Champaign, Ill, USA, 5th edition, 1998.
[24]
Y. H. Chen and Y. M. Luo, “Oxidation stability of biodiesel derived from free fatty acids associated with kinetics of antioxidants,” Fuel Processing Technology, vol. 92, no. 7, pp. 1387–1393, 2011.
[25]
Fat and Oil Derivatives—Fatty Acid Methyl Esters (FAME), “Determination of oxidation stability (accelerated oxidation test),” EN 14112:2003, European Committee for Standardization, Berlin, Germany, 2003.
[26]
“Standard test method for density, relative density, and API gravity of liquids by digital density meter,” ASTM D4052—09, ASTM International, 2002.
[27]
“Standard test methods for flash point by Pensky-Martens closed cup tester,” ASTM D93—10a, ASTM International, 2001.
[28]
“Standard test method for acid number of petroleum products by potentiometric titration,” ASTM D664—11, ASTM International, 2001.
[29]
“Standard test method for determination of total monoglyceride, total diglyceride, total triglyceride, and free and total glycerin in B-100 biodiesel methyl esters by gas chromatography,” ASTM D6584—10ae1, ASTM International, 2003.
[30]
Fat and oil derivatives—Fatty Acid Methyl Esters (FAME), “Determination of ester and linolenic acid methyl esters content,” EN 14103:2003, 2003.
[31]
STATISTICA for Windows Software. v. 9. 0, Tulsa, OK, USA, 2009.
[32]
V. Calado and D. C. Montgomery, Planejamento De Experimentos Usando O Statistica, E-Papers Servi？os Editoriais, Rio de Janeiro, Brazil, 2003.
[33]
J. A. Cornell, Experiments With Mixtures—Designs, Models and the Analysis of Mixture Data, John Wiley and Sons, New York, NY, USA, 2002.
[34]
I. P. Lobo, S. L. C. Ferreira, and R. S. D. Cruz, “Biodiesel: quality parameters and analytical methods,” Quimica Nova, vol. 32, no. 6, pp. 1596–1608, 2009.
[35]
Brasil. Resolu？？o no 14, de 11 de maio de 2012 da ANP, Agência Nacional do Petróleo, Gás Natural e Biocombustíveis.Estabelece a especifica？？o para a comercializa？？o de biodiesel que poderá ser adicionado ao óleo diesel. Diário Oficial da Uni？o, Brasília, 18 de maio de 2012.
[36]
F. Karaosmanoglu and U. G. Becker, “Used oil as a fuel oil alternative,” Energy Source, vol. 18, pp. 637–644, 1996.
[37]
D. Borsato, L. H. Dall'antonia, C. L. B. Guedes et al., “The simplex-centroid design applied to study of the kinetics of the oxidation of B100 biodiesel in blend with synthetic antioxidants,” Quimica Nova, vol. 33, no. 8, pp. 1726–1731, 2010.
[38]
R. M. Silverstein and F. X. Webster, IDentifica？ao Espectrométrica De Compostos Organicos, LTC:, Rio de Janeiro, Brazil, 2000.
[39]
E. N. Frankel, “In search of better methods to evaluate natural antioxidants and oxidative stability in food lipids,” Trends in Food Science and Technology, vol. 4, no. 7, pp. 220–225, 1993.
[40]
E. N. J. Frankel, “Review. Recent advances in lipid oxidation,” Journal of the Science of Food and Agriculture, vol. 54, pp. 495–511, 1991.
[41]
G. L. Hasenhuettl and P. J. Wan, “Temperature effects on the determination of oxidative stability with the metrohm rancimat,” Journal of the American Oil Chemists Society, vol. 69, no. 6, pp. 525–527, 1992.
[42]
J. Xin, H. Imahara, and S. Saka, “Kinetics on the oxidation of biodiesel stabilized with antioxidant,” Fuel, vol. 88, no. 2, pp. 282–286, 2009.
[43]
S. Mali, R. A. S. Silva, M. V. E. Grossmann, R. S. F. Silva, and D. Borsato, “Optimization of the production of acetylated distarch adipates using the novel software 'MULTIPLEX',” International Journal of Food Science and Technology, vol. 36, no. 6, pp. 641–647, 2001.
[44]
E. C. R. Maia, D. Borsato, I. Moreira, K. R. Spacino, P. R. P. Rodrigues, and A. L. Gallina, “Study of the biodiesel B100 oxidative stability in mixture with antioxidants,” Fuel Processing Technology, vol. 92, no. 9, pp. 1750–1755, 2011.
[45]
K. M. Lee and D. F. Gilmore, “Formulation and process modeling of biopolymer (polyhydroxyalkanoates: PHAs) production from industrial wastes by novel crossed experimental design,” Process Biochemistry, vol. 40, no. 1, pp. 229–246, 2005.
