Journal of Industrial and Engineering Chemistry, Vol.46, 266-272, February, 2017
Synthesis of potassium glyceroxide catalyst for sustainable green fuel (biodiesel) production
Metal hydroxides and alkoxides are used as base catalysts for biodiesel production. When metal hydroxides are dissolved in alcohol, they produce water, which can react with triglycerides (TGs) and produce free fatty acids (FFAs) rather than the desired fatty acid alkyl esters. Metal alkoxides are more expensive to produce and their transportation is hazardous. In this study, potassium alkoxide catalysts were synthesized from potassium hydroxide (KOH) solution and glycerol, which is by-product of biodiesel production process, by heating 50% KOH solution and glycerol at different mole ratios, temperatures and vacuum pressures. These operating parameters were optimized and their interactive effect on catalyst synthesis was studied by using response surface methodology (RSM). This study also focused on the development of a correlation relating the effects of these variables with drying behavior of reagents during catalyst synthesis. The results indicated that KOH to glycerol mole ratio and vacuum pressure had the most significant effects (P < 0.0001) on free water mass loss during catalyst synthesis. The optimum reaction condition was KOH to glycerol mole ratio of 2:1, reaction temperature 130 °C and vacuum pressure 113 mbar. X-ray powder diffraction showed that glycerol derived alkoxide compounds were predominantly monopotassium substituted alkoxides that occur as adducts with potassium hydroxide. The glyceroxide catalyst prepared at 3:1 mole ratio of KOH:glycerol has improved biodiesel yield to that of conventional potassium methoxide (KOCH3) catalyst.
- Basu HN, Norris ME, US Patent 5, 1996, 525:126.
- Liu KS, J. Am. Oil Chem. Soc., 71, 1179 (1994)
- Morrison LR, in: Kirk RE, Othmer DF (Eds.), Encyclopedia of Chemical Technology, John Wiley & Sons, Inc., New York, 2000.
- Engelhaupt E, Environ. Sci. Technol., 41, 5175 (2007)
- Kapicak LA, Schreck DJ, US Patent 2010/0048941 A1, 2008.
- Reaney MJT, Westcott ND, WO 2007/022621 A2.
- Reaney MJT, Liu YD, Westcott ND, US Patent 6, 2002, 414:171.
- Reaney MJT, Shen J, Soveran DW, US 2010/0305344 A1.
- Jeong GT, Park DH, Appl. Biochem. Biotechnol., 156(1-3), 431 (2009)
- Gunawan ER, Basri M, Rahman MBA, Salleh AB, Rahman RNZA, Enzyme Microb. Technol., 37(7), 739 (2005)
- Demirkol S, Aksoy HA, Tuter M, Ustum G, Sasmaz DA, J. Am. Oil Chem. Soc., 83, 929 (2006)
- Rashid U, Anwar F, Ansari TM, Arif M, Ahmad M, J. Chem. Technol. Biotechnol., 84(9), 1364 (2009)
- Pradhan S, Madankar CS, Mohanty P, Naik SN, Fuel, 97(-), 848 (2012)
- Pradhan S, Shen J, Emami S, Naik SN, Reaney M, Eur. J. Lipid Sci. Technol., 116, 1590 (2014)
- Das SK, Mohanty P, Majhi S, Pant KK, Appl. Energy, 111(-), 267 (2013)
- Nanda S, Mohanty P, Kozinski JA, Dalai AK, Energy Environ. Res., 4, 21 (2014)
- Lawrance GA, Robertson MJ, Sutrisno, von Nagy-Felsobuki EI, Inorg. Chim. Acta., 328, 159 (2002)
- PospIsilova M, Polasek M, Prochazka J, J. Chromatogr. A, 772, 277 (1997)
- Rendleman JA, J. Org. Chem., 31, 1839 (1996)
- Khuri AI, Cornell JA, Response Surfaces: Design and Analysis, Marcel Dekker, New York, 1987.
- Gok HYF, Emami S, Shen J, Reaney MJT, J. Am. Oil Chem. Soc., 90, 299 (2013)
- Schatte G, Shen J, Reaney M, Sammynaiken R, Acta Crystallogr. Sect. E, 67, m141 (2011)
- Jang MG, Kim DK, Park SC, Lee JS, Kim SW, Renew. Energy, 42(-), 99 (2012)