Production of Biodiesel in Supercritical Methanol and Related Correlation on Phase Equilibrium

Abstract:

Biodiesel was prepared by methyl esterification and effects of different reaction conditions on the yield of fatty acid methyl esters (FAMEs) were investigated. The result of the orthogonal experiment analysis shows that the order of influential factors is ranked as reaction temperature > methanol-to-soybean-oil (M/O) ratio > reaction time. The maximum yield of 94.8 % has been achieved by reacting supercritical methanol and soybean oil in M/O ratio 4:2 (v/v) at 573 K for 45 min. Moreover, the higher M/O ratio, the higher yield of FAMEs will be obtained. At the temperature ranging from 533 k to 573 k, the yield rises significantly; however, since soybean oil decomposes over 573 K, the yield decreases oppositely. Time longer than 45 min has less effect on the final yield. In addition, the phase equilibrium data of supercritical methanol + C12 methyl esters and supercritical methanol + C18 methyl esters were separately correlated using the Peng-Robinson (PR) equation of state (EOS) with the Adachi-Sugie (AS) mixing rule.

• Periodical: Advanced Materials Research (Volumes 560-561)
• Pages: 555-562
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.560-561.555
• Online since: August 2012
• Authors: Dan Zeng, Yang Li, Tao Fang
• Keywords: Bio-Diesel, Methyl Esterification, Phase Equilibrium, Supercritical Methanol

References

[1] J. F. Zhou, The phase behavior and mechanism of biodiesel production in supercritical methanol, Wuhan institute of technology, May 2008. (in Chinese).

[2] B. Yang, Kinetics of synthesizing biodiesel in supercriticalm ethanol, Zhejiang University, August 2007. (in Chinese).

[3] Markets and Markets. Global Biodiesel Market. March (2010).

[4] S. Y. Sun, H. Y. He, L. Y. Wang, J. C. Yang, Production of biodiesel in supercritical methanol, Fine Chemicals. 22 (2005) 916-919. (in Chinese).

[5] M. Xiao, Q. L. Xu, J. Z. Yin, Advancement of biodiesel production by use of supercritical methanol technology, Biotechnology Bulletin. 1 (2007) 96-98. (in Chinese).

[6] Swern, D., Qin Hong-wan, Bailey's industrial oil and fat products, Beijing: Light Industry Press. October (1989).

[7] T. Fang, Motonobu, et al, Separation of natural tocopherols from soybean oil byproduct with supercritical carbon dioxide, J. of Supercritical Fluids. 40 (2007) 50-58.

DOI: 10.1016/j.supflu.2006.04.008

[8] W. Weber, S. Petkov, G. Brunner, Vapor–liquid-equilibria and calculations using the Redlich-Kwong-Aspen-equation of state for tristearin, tripalmitin and triolein in CO2 and propane, Fluid PhaseEquilib. 158 (1999) 695-706.

DOI: 10.1016/s0378-3812(99)00114-4

[9] Y. Shimoyama, Y. Iwai, Bo Seok Jin, T. Hirayama, Y. Arai, Measurement and correlation of vapor-liquid equilibria for methanol + methyl laurate and methanol + methyl myristate systems near critical temperature of methanol, Fluid Phase Equilibria. 257 (2007).

DOI: 10.1016/j.fluid.2007.01.034

[10] T. Fang, Y. Shimoyamab, T. Abetab, et al, Phase equilibria for the mixtures of supercritical methanol + C18 methyl esters and supercritical methanol +α-tocopherol, J. of Supercritical Fluids. 47 (2008) 140-146.

DOI: 10.1016/j.supflu.2008.07.020

[11] B.E. Poling, J.M. Prausnitz, J.P. O'Connell, The properties of gases and liquids, 5th ed., McGraw-Hill, New York, (2001).

[12] D. Ambrose, Trans. Faraday Soc. 59 (1963).

[13] L. Constatinou, R. Gani, AIChE J. 40 (1994) 1697-1710.

[14] T. Boublik, V. Fried, E. Hala, The vapor pressures of pure substances, Elsevier Science Pub., Amsterdam. (1984) 869-870, 890-891.

[15] J. Marrero, R. Gani, Group-contribution based estimation of pure component properties, Fluid Phase Equilib. (2001) 183-208.

DOI: 10.1016/s0378-3812(01)00431-9

[16] L. Constantinou, R. Gani, J.P. O'Connell, Estimation of the acentric factor and the liquid molar volume at 298K using a new group contribution method, Fluid Phase Equilib. 103 (1995) 11-22.

DOI: 10.1016/0378-3812(94)02593-p