การผลิตไบโอดีเซลจากน้ำมันปาล์มอย่างมีประสิทธิภาพในเครื่องปฏิกรณ์แบบจานหมุน

Abstract

This research studied the kinetics of transesterification of palm oil and the appropriate condition for producing biodiesel from refined palm oil via transesterification in spinning disc reactor with Response Surface Methodology (RSM) and Central Composite Design (CCD). It focused on variables affecting the percentage of methyl ester yield: the loading of NaOH catalysts, the rotational speed of the disc, and the total flow rate of feed together with the comparison of the efficiency of a mechanical stirrer reactor and a high shear reactor. The researcher conducted the experiment on the kinetics of transesterification of palm oil in a mechanical stirrer reactor, a high shear reactor and a spinning disc reactor at the operating condition of the oil to methanol molar ratio of 1:6, catalyst loading of 1.0 %wt of oil and the reaction temperature of 60 °C. The biodiesel production using a spinning disc reactor was also investigated by changing the loading of NaOH catalysts from 0.5 to 1.25 %wt of palm oil, the rotational speed of the disc from 500 to 2000 rpm and the total flow rate of feed from 130 to 390 ml/min with the palm oil to methanol molar ratio of 1:6 and the reaction temperature of 60 °C. The findings revealed that the constant rate of transesterification of palm oil was 0.0438, 0.0738 and 1711.5 per minute when using a mechanical stirrer reactor, a high shear reactor and a spinning disc reactor, respectively. The appropriate condition for producing biodiesel by using a spinning disc reactor was the catalyst loading of 1.25 %wt of palm oil, the rotational speed of the disc of 1028 rpm and the total flow rate of 156.3 ml/min. This resulted in the percentage of methyl ester yield of 97.9 whose residence time was merely 4.03 seconds when compared with the reaction time spent in a mechanical stirrer reactor and that in a high shear reactor of 60 and 30 minutes, respectively. Regarding the comparison of yield efficiency of biodiesel gained from the spinning disc reactor, it was found that the yield efficiency was 1.4451 X10-1 g/J which was higher than that of the mechanical stirrer reactor and the high shear reactor for up to 65000 times. It could be concluded that the spinning disc reactor was a high efficiency reactor for continuous biodiesel production.