Co-solvent transesterification of bitter almond oil into biodiesel: optimization of variables and characterization of biodiesel
Abstract
The influence of co-solvent on transesterification of one of non-edible feedstocks, Bitter Almond Oil (BAO) with methanol was investigated. Hexane and potassium hydroxide (KOH) were chosen as the co-solvent and the catalyst, respectively. The variables included in the optimization process were concentration of KOH, methanol to oil molar ratio, hexane to methanol volume ratio, temperature, time, type of co-solvent and type of alkali catalyst. BioDiesel (BD) with yield of 97.88…98.50 ester content % w/w were obtained using 0.60% KOH w/w, 5:1 methanol to oil molar ratio, 1:1 hexane to methanol volume ratio, 32 °C reaction temperature and 45 minutes of reaction. The Fourier Transform InfraRed (FTIR) spectroscopy and Thin Layer Chromatography (TLC) were used to ensure the conversion of BAO into BD. The fuel properties of the prepared BD were determined and found within the acceptable limits prescribed by ASTM D6751-15ce1 and EN 14214:2017. Moreover, properties of (biodiesel + petro-diesel) blends complied with the limits prescribed in the ASTM D7467-17 standards as well. It was concluded that the presence of co-solvent reduced the concentration of the catalyst, temperature, methanol to oil molar ratio and time required to produce maximum yield of BD comparing to non-solvent process. As a result, co-solvent transesterification is recommended for further application.
Keyword : bitter almond oil, co-solvent transesterification, biodiesel, fuel properties, analysis of biodiesel, blending evaluation
How to Cite
Fadhil, A. B., & Mohammed, H. M. (2018). Co-solvent transesterification of bitter almond oil into biodiesel: optimization of variables and characterization of biodiesel. Transport, 33(3), 686-698. https://doi.org/10.3846/16484142.2018.1457568
This work is licensed under a Creative Commons Attribution 4.0 International License.
References
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ASTM D1747-09(2014). Standard Test Method for Refractive Index of Viscous Materials.
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ASTM D93-16a. Standard Test Methods for Flash Point by Pensky-Martens Closed Cup Tester.
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Cunha, A.; Feddern V; De Prá, M. C.; Higarashi M. M.; De Abreu P. G.; Coldebella, A. 2013. Synthesis and characterization of ethylic biodiesel from animal fat wastes, Fuel 105: 228–234. https://doi.org/10.1016/j.fuel.2012.06.020
Dias, J. M.; Alvim-Ferraz, M. C. M.; Almeida, M. F. 2009. Production of biodiesel from acid waste lard, Bioresource Technology 100(24): 6355–6361. https://doi.org/10.1016/j.biortech.2009.07.02
Ejikeme, P. M.; Anyaogu, I. D.; Egbuonu, C. A. C.; Eze, V. C. 2013. Pig-fat (lard) derivatives as alternative diesel fuel in compression ignition engines, Journal of Petroleum Technology and Alternative Fuels 4(1): 7–11. https://doi.org/10.5897/JPTAF10.001
EN 14214:2017. Liquid Petroleum Products – Fatty Acid Methyl Esters (FAME) for Use in Diesel Engines and Heating Applications – Requirements and Test Methods.
Encinar, J. M.; González, J. F.; Pardal, H.; Martínez, G. 2010. Transesterification of rapeseed oil with methanol in the presence of various co-solvents, in Proceedings Venice 2010: Third International Symposium on Energy from Biomass and Waste, Venice, Italy, 8–11 November 2010, 1–17.
Encinar, J. M; González, J. F; Rodríguez-Reinares, A. 2007. Ethanolysis of used frying oil. Biodiesel preparation and characterization, Fuel Processing Technology 88(5): 513–522. https://doi.org/10.1016/j.fuproc.2007.01.002
Encinar, J. M; Sánchez, N.; Martínez, G.; García, L. 2011. Study of biodiesel production from animal fats with high free fatty acid content, Bioresource Technology 102(23): 10907–10914. https://doi.org/10.1016/j.biortech.2011.09.068
Fadhil, A. B. 2013a. Biodiesel production from beef tallow using alkali-catalyzed transesterification, Arabian Journal for Science and Engineering 38(1): 41–47. https://doi.org/10.1007/s13369-012-0418-8
Fadhil, A. B. 2013b. Optimization of transesterification parameters of melon seed oil, International Journal of Green Energy 10(7): 763–774. https://doi.org/10.1080/15435075.2012.727200
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