Transesterification of waste frying oil under ultrasonic irradiation
This study investigates the effect of ultrasounds in conversion of waste frying oil into biodiesel. Many researchers have studied the use of ultrasounds in the biodiesel production from different feedstock; however, there are few studies focused on the biodiesel production from waste frying oil. In this research, ultrasound-assisted transesterification was carried out to convert the waste frying oil into biodiesel directly. The effect of different process parameters such as reaction time (30-90 min), amount of catalyst (0.5 -1% wt. NaOH) and temperature (20-40 ºC) were also analyzed to obtain the higher conversion. A methanol to oil molar ratio of 6:1, 0.5% amount of catalyst and 30 ºC was enough to complete the process in 60 min. The obtained results in this study confirm that that ultrasound-assisted transesterification was a fast and efficient method for biodiesel production from waste frying oil even if reaction temperature is low.
Keywords: ultrasound transesterification, waste frying oil, biodiesel.