Transesterification of microalgae for biodiesel production

Abstract

This chapter explores the options of using microalgae oil for biodiesel synthesis. It provides general knowledge about the chemical processes taking place during the transesterification of lipids and the acylation agents and catalysts used in these processes. The section provides an overview of the conditions of homogeneous (acid and alkaline) catalysis and the efficiency of these processes when they are applied in the transesterification of various kinds of microalgae oil. The analysis shows options that use various heterogeneous catalysts by focusing on the processes of enzymatic catalysis. Information is provided on the sources, properties, and efficiency of lipases in catalyzing the reactions of transesterification of microalgae oil with methanol and ethanol and on ways to increase process efficiency. Considering that the solubility of alcohols in oil under supercritical conditions is higher than in other conditions, this chapter examines options that use such a process for biodiesel synthesis. A large share of consumed energy is used for drying microalgae biomass and isolating oil; therefore, this book discusses options to apply a process that simultaneously extracts algae oil and transesterifies it in situ using both wet and dried microalgae biomass for this purpose.