Biodiesel Production in Supercritical Methanol Using a Novel Spiral Reactor

Biodiesel was produced via non-catalytic transesterification in supercritical methanol using a novel spiral reactor. This spiral reactor could serve as a heat exchanger, thus it provided the advantage of being able to recover the heat. Transesterification was carried out at 270-400°C, a pressure of 20 MPa, oil-to-methanol molar ratio of 1:40, and reaction time of 3-30min. Using this technique, a complete conversion of fatty acid methyl ester (FAME) (100 wt%) was obtained in a short reaction time of 10 min at 350°C and oil-to-methanol molar ratio of 1:40 under a reactor pressure of 20 MPa. The result revealed that biodiesel yield conducted in spiral reactor is higher than that in batch reactor at the same reaction conditions. The kinetic model of canola oil conversion to biodiesel in supercritical methanol was also determined.