from first principles PP-I-1

PP-IV-24Combined Methods for Mono-, Di- and Triglycerides Determination:A Biodisel Production over CaO CatalystVasic M. 1 , Ljupkovic R. 1 , Radulovic N. 1 , Putanov P. 2 , Momcilovic M. 3 , Zarubica A. 11 University of Nis, Faculty of Science and Mathematics, 18000 Nis, Serbia2 Serbian Academy of Science and Arts, 11000 Belgrade, Serbia3 Institute for Nuclear Sciences “Vinca”, 11000 Belgrade, Serbiazarubica2000@yahoo.comBiodiesel has been considered as a promising responce to environmental, economic, andpolitical problems concerning fossil fuels. Its advantages are: renewability, bio-degradability,low cost, and environmental suitability. Biodisel is a mixture of fatty acids methyl esters(FAME) obtained in a catalyzed reaction of transesterification of methanol and vegetable oilsor animal fats. Commercial sunflower oil was used as the raw material for biodiesel synthesis.GC-MS analysis determined the oil fatty acid profile: palmitic acid (9.20%), linoleic acid(61.20%), oleic acid (19.30%) and stearic acid (6.44%). Transesterification reaction wascarried out with methanol-to-oil molar ratio = 1:6 using 1% CaO as catalyst, at 65°C and1 atm, for 5h with time increments of 1h. The obtained FAME were analyzed using GC-MS(Hewlett-Packard series 6890N), equipped with MS detector and a capillary column DB-5.The related GC FAME peaks were detected as follows: methyl palmitate, methyl linoleate,methyl oleate, and methyl stearate, based on the corresponding retention indexes. Theestimated average biodisel yield was 90.9%.As supplemental method, reversed-phase high-performance liquid chromatography (RP-HPLC) was used for determination of total TGs, diacylgycerols (DGs), monoacylglycerols(MGs) and FAME. The method was used for analysis of early aliquots, composed ofunreacted mixture of TGs, DGs and MGs, and quantitation of residual TGs in the finalproduct. Non-aqueous mobile phase composed of 30% acetone + 70% acetonitrile (v/v), andC18 column without linear gradient, and UV detection at 220 nm were used.A simple combination of adequate GC and/or HPLC methods has been modified and adapted tobe used as an analytical tool for the full charactrization of FAME and residual transesterificationreaction intermediates (total TGs, DGs and MGs). Such combined methods excluded additionalneed for use of derivatization techniques for particular compounds analysis.Acknowledgements: The authors wish to thank to Project of Serbian Academy of Science and Arts andProject ON 172061 of the Serbian Ministry of Education and Science for financial supports.309