New approach of catalyst-free biodiesel production from canola oil in supercritical tert-butyl methyl ether (MTBE)

This paper reports a novel approach for biodiesel production from canola oil in supercritical tert-butyl methyl ether (MTBE) without the addition of a catalyst. Using this technique, canola oil was reacted with MTBE to generate fatty acid methyl esters (FAMEs) and glycerol tert-butyl ether. No glycerol was obtained as a by-product in this reaction. The effects of temperature, pressure, and reaction time on product yield were investigated in supercritical MTBE. A FAME yield of 0.94 was obtained in a short reaction time of 12 min at 400 °C, with a molar ratio of MTBE-to-oil of 40:1, and under a pressure of 10 MPa. The kinetics of the reaction was first order, and the activation energies and pre-exponential factors were calculated from the temperature dependence of the reaction rate constants.