Ultrasound was used in transesterification of palm oil. The effects of ultrasonic power, reaction time, molar ratio of methanol to oil and reaction temperature on the transesterification rate were investigated. Based on single factor experiment, the optimal ultrasound-assisted transesterification conditions were obtained by orthogonal experiment as follows: ultrasonic power 280 W, reaction time 30 min, molar ratio of methanol to oil 7.5∶1 and reaction temperature 55℃.Under these conditions, the transesterification rate was 95.5%. Compared with the conventional stirring transesterification method, ultrasound-assisted method markedly promoted the transesterification in reductions of reaction temperature and reaction time. |