Effects of free fatty acid, moisture content, and working volume on biodiesel production from palm oil using a non-catalyzed supercritical process (II)

In this study, the effects of free fatty acid and moisture content in palm oil, and the working volume on the production of fatty acid methyl ester were investigated using palm oil and non-catalytic supercritical process. In the non-catalytic supercritical process, FAME content obtained using anhydrous palm oil was 95.8%. Moreover, FAME content produced by 15% moisture content and 15% free fatty acid content were 94.4% and 95.1% respectively, which had similar result to anhydrous palm oil with no-FFA. In this study, non-catalytic supercritical process did not affected by the content of free fatty acid and moisture in oil. In the supercritical experiment, changing of temperature and pressure was conducted by changing of working volume in the supercritical reaction. The pressure is proportionally increased to working volume at the temperature over 180°C. Therefore, in high working volume, constant pressure was rapidly reached at low temperature. In the experiment of the effect of working volume on FAME production using non-catalytic supercritical reaction, the highest FAME content of 95.5% was obtained in the condition of working volume of 275 mL and reaction time of 10 min. We found that, by increasing the working volume at same pressure, the reaction temperature is decreased from 340°C to 260°C, but the FAME content was increased from 69.9% to 95.5%.