Abstract
The production of biofuels has a great impact on the economy and society.
Biodiesel is a sustainable liquid fuel used for partial or full replacement of standard
diesel fuel, and its production generates valuable by-products. The use of ultrasound in
biodiesel production has a growing interest due to several advantages; it significantly
reduces the reaction time and avoids the use of heating, reaching similar or higher
FAME yield. The application of ultrasounds in homogeneous and heterogeneous
catalysis processes is reported to be technically feasible, but several issues are to be
considered such as the corrosion effect on sonotrodes, and the effect of ultrasounds
waves on solid catalyst surface and pores. Combining it with microwave irradiation
might be an effective procedure for the intensification of biodiesel production,
especially with heterogeneous catalysis. Technical challenges are associated with the
design of large-scale reactors in which both types of energy could be applied
concurrently with cost reduction. This chapter explores the basis of ultrasounds and
their use in the production of biodiesel, its main features, and challenges.
Keywords: Biodiesel, Cavitation, FAME, Transesterification, Ultrasounds.