Is Thermogravimetry an efficient alternative to gas chromatography in degree of biodiesel conversion?
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This work aims to determine if thermogravimetry could be used to determine the degree of conversion of soybean oil to biodiesel without knowing the amount of ester in the sample, comparing the results with the values obtained by the standard method, gas chromatography. The syntheses were made using homogeneous and heterogeneous catalysts, and the measures were made in triplicate on both pieces of equipment. The average values (%) obtained were 74.59 ± 0.58, 66.5 ± 1.62, 13.54 ± 0.32 by thermogravimetry and 74.09 ± 0.46, 62.08 ± 2.19, 17.07 ± 0.31 by gas chromatography. These data were statistically compared using F-test, and the result indicated that the thermogravimetry could be used as analytical technique to determine the degree of conversion of biodiesel, with the same reliability as gas chromatography. The thermogravimetry shows more advantages than gas chromatography, because it does not require organic solvent, following the Green Chemistry Principles, and it is already used to determine other thermal properties of biodiesel.
KeywordsBiodiesel Degree of conversion Thermogravimetry Gas Chromatography Green Chemistry
The authors wish to thank CAPES (Proc. 024/2012 Pro-equipment), CNPq (Proc. No. 421469/2016-1), POSMAT/UNESP and FAPESP (Proc. No. 2017/14936-9 and No. 2017/08820-8) for financial support and the Ph.D. Manoel Lima de Menezes for help.
- 1.Knothe G, Van Gerpen J, Krahl J, Ramos LP. Biodiesel manual. São Paulo: Edgard Blücher; 2006.Google Scholar
- 2.Baird C, Cann M. Environmental chemistry. 4th ed. New York: W. F. Freeman and Company; 2008.Google Scholar
- 3.OECD/Food and Agriculture Organization of the United Nations. OECD-FAO Agricultural outlook 2015, OECD publishing; 2015.Google Scholar
- 4.ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. NBR 15764: Biodiesel—Determinação do teor total de ésteres por cromatografia gasosa; 2015.Google Scholar
- 5.DIN EN14103 Fat and oil derivatives- Fatty acid methyl esters (FAME)—Determination of ester and linolenic acid methyl esters content. Brussels: European Commitee for Standartization, Management Centre; 2011.Google Scholar
- 21.Menezes ML, Lopes LFS, Passaretti Filho J. Síntese de biodiesel empregando óleo de abacate. Rev Anal. 2010;44:68–78.Google Scholar
- 22.Miller JN, Miller JC. Statistics and chemometrics for analytical chemistry. 6th ed. Harlow: Pearson Education Limited; 2010.Google Scholar