Performance comparison of different cavitation reactors for biodiesel production via transesterification of palm oil

Abstract

This study compares performance of different cavitation reactors for biodiesel production from palm oil using homogeneous and heterogeneous reaction systems. In addition, the effect of reaction volume of each reactor type was also investigated. For the smallest reaction volume of 165 mL, homogenizer and 20 kHz ultrasonic reactors offered the highest fatty acid methyl ester yield for both sodium hydroxide and calcium oxide catalysts. When the reaction volume was increased from 165 to 500 and 1000 mL with constant power input (80 W), homogenizer reactor did not significantly alter the rate of fatty acid methyl ester formation, unlike the other reactors which showed the decrease in the reaction rate. The reactor performance was evaluated in term of yield efficiency which was based on the amount of fatty acid methyl ester production, power consumption and reaction time. The increase of the reaction volume increased the yield efficiency of both the cavitation reactors and the mechanical stirred reactor. The highest yield efficiencies of 169.46 × 10−4 and 8.27 × 10−4 g/J were obtained from homogenizer reactor using sodium hydroxide and calcium oxide catalysts, respectively, using the reaction volume of 1000 mL. The homogenizer reactor also shows high flexibility of reaction volume usage with high biodiesel production performance in a batch system.