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Spectroscopic Study of Biodiesel Degradation Pathways
Technical Paper
2006-01-3300
ISSN: 0148-7191, e-ISSN: 2688-3627
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Abstract
Oxidative degradation of biodiesel under accelerated conditions has been examined by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and gravimetric measurement of deposit formation. The formation of gums and deposits caused by oxidation in storage or in an engine fuel system is a significant issue because of the potential for fuel pump and injector fouling. The results of this study indicate several important pathways for degradation and two pathways leading to formation of oligomers and, ultimately, deposits. Peroxides formed in the initial stage of oxidation can decompose to form aldehydes, ketones, and acids. These can react further in aldol condensation to form oligomers. Additionally, peroxides can react with fatty acid chains to form dimers and higher oligomers. Deposits form when the polarity and molecular weight of these oligomers is high enough. An antagonistic effect on deposit formation is observed for ultra-low sulfur diesel-(ULSD) biodiesel blends because of the lower polarity of ULSD relative to higher sulfur grades of diesel. Additionally, methyl esters can decompose by hydrolysis, reverse transesterification through reaction with glycerin and glycerides, and other related mechanisms. The use of antioxidants at the point of manufacture to prevent formation of hydroperoxides is recommended.
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Fang, H. and McCormick, R., "Spectroscopic Study of Biodiesel Degradation Pathways," SAE Technical Paper 2006-01-3300, 2006, https://doi.org/10.4271/2006-01-3300.Data Sets - Support Documents
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References
- Sheehan, J. Camobreco, V. Duffield, J. Graboski M. Shapouri, H. “An Overview of Biodiesel and Petroleum Diesel Life Cycles” May 1998
- United States Environmental Protection Agency 2002 “A Comprehensive Analysis of Biodiesel Impacts on Exhaust Emissions” Draft Technical Report
- Graboski, M.S. McCormick, R.L. “Combustion of Fat and Vegetable Oil Derived Fuels in Diesel Engines.” Progress in Energy and Combustion Science 24 125 1998
- Ingold, K. U. “Peroxy Radicals” Acc. Chem. Res. 2 1 1969
- Frankel, E.N. “Lipid Oxidation” The Oily Press, Ltd Dundee 1998
- Neff, W. E. Frankel, E. N. Fujimoto, K. J. Am. Oil Chem. Soc. 65 616 1988
- McCormick, R.L. Alleman, T.L. Ratcliff, M. Moens, L. Lawrence, R. “Survey of the Quality and Stability of Biodiesel and Biodiesel Blends in the United States in 2004” Oct. 2005
- Cosgrove, J. P. Church, D. F. Pryor, W. A. “The Kinetics of The Autoxidation of Polyunsaturated Fatty Acids.” Lipids 22 299 1987
- Knothe, G. “Structure Indices in FA Chemistry” Journal of the American Oil Chemists Society 79 9 847 2002
- Fang, H. L. Stehouwer, D. M. Wang, J. “Interaction between Fuel Additive and Oil Contaminant: (II) Its Impact on Fuel Stability and Filter Plugging Mechanism” SAE 2003-01-3140
- Knothe, G. Dunn, R.L. “Dependence of Oil Stability Index of Fatty Compounds on Their Structure and Concentration and Presence of Metals” Journal of the American Oil Chemists Society 80 10 1021 2003
- Fang, H.L. “Deposit Formation, Glycerin Limit and Organo-nitrate Impact on Biodiesel Blends”
- McCormick, R.L. Ratcliff, M. Moens, L. Lawrence, R. “Factors Affecting the Stability of Biodiesel Sold in the United States” Prepr. Pap.-Am. Chem. Soc., Div. Fuel Chem. 51 1 14 2006