This paper investigates a new route for intensification of methyl ester synthesis in Malaysia via alkalicatalysed
transesterification of waste cooking oil derived from palm olein using a hydrodynamic
cavitation reactor. The effects of the oil to methanol molar ratio (1:4–1:7), catalyst loading concentration
(0.5–1.25 wt%) and reaction temperature (50–65 C) have been investigated using an optimised plate
with 21 holes of 1 mm diameter and an inlet pressure of 2 bar in a 50 L of hydrodynamic cavitation reactor
assisted by a double diaphragm pump. Optimal conversion of 98.1% was achieved in 15 min in a
hydrodynamic cavitation reactor with 1:6 molar ratio of oil to methanol, 1 wt% of catalyst and 60 C of
reaction temperature. It has been observed that a significant reduction in the optimum reaction time
(about 6 fold) for transesterification from 90 min for mechanical stirring approach to 15 min for the
hydrodynamic cavitation approach. Optimal yield efficiency of 12.50
104 g/J was found using
hydrodynamic cavitation and it was 8 fold higher than 1.5
104 g/J when mechanical stirring was used.