Biological Methods in Biodiesel Production and Their Environmental Impact

Abstract

This publication presents the technologies of enzymatic biodiesel production in comparison to the conventional methods using acid and base catalysts. Transesterification with conventional catalysts has some disadvantages, and for this reason, alternative methods of biodiesel production have been investigated. These solutions include the replacement of chemical catalysts with biological ones, which show substrate specificity in relation to fats. Replacing chemical with biological catalysts causes elimination of some disadvantages of chemical processes, for instance: high temperatures of reaction, problematic process of glycerol purification, higher alcohol-to-oil molar ratios, and soap formation. Moreover, it causes operational cost reduction and has a positive environmental impact. This is due to the lower temperature of the process, which in turn translates into lower cost of equipment and lower GHG emissions associated with the need to provide less heat to the process. The increase of biofuels’ demand has led to the technology of enzymatic biodiesel production being constantly being developed. This research mainly focuses on the possibility of obtaining cheaper and more effective biocatalysts, as well as increasing the durability of enzyme immobilization on different materials.

Transesterification of waste cooking oil with a commercial liquid biocatalyst: Key information revised and new insights

“…Moreover, the enzymatic catalysis has received a considerable attention since lipases can resist both high water content and concentration of free fatty acids therefore low quality oils are suitable substrates. Besides, the transesterification of oils through enzymatic catalysis is considered a greener route than the alkaline (and acid) catalysis because consumes less energy (operates at lower temperature than the alkaline counterpart), generates clean glycerol, eliminates soap formation, and avoids the use of large amounts of water required for the purification of the methyl esters (Biernat et al, 2021).…”