Enzymatic synthesis of biodiesel showed advantageous characteristics in relation to other technologies once it works under bland conditions, no generation of wastewater, no occurrence of saponifications reactions and production of a biodiesel with high quality. Although many researches still apply immobilized lipases, the high costs associated with this biocatalyst hamper the economic viability of the process. Lipases in free/soluble/liquid formulation employed to biodiesel production via hydroesterification reaction have attracted interest from researchers because they are more cost effective than the immobilized form, making the enzymatic route more competitive. In addition, soluble lipases present higher reaction rates, reducing the time required to obtain a satisfactory biodiesel yield. Despite the fact that already exist industrial plants producing biodiesel with the assistance of lipases in liquid formulation, results of researches show that the process still needs to overcome some drawbacks. This paper is a comprehensive and critical discussion on the publications where soluble lipases were applied on biodiesel synthesis, as well as the challenges that the technology faces and its current status in pilot and industrial applications.
Biodiesel production through the transesterification of oleaginous sources utilizing alkaline catalysts shows many process drawbacks like the need of a raw material with high purity degree and a high amount of alkaline wastewater generated from the biodiesel washing step. Such drawbacks can be overcome using enzymes as catalysts. In this context, the commercial Callera™ Trans L lipase arises as an interesting alternative catalyst for hydrolysis‐esterification reaction. In order to evaluate the use of Callera™ Trans L on biodiesel synthesis and optimize the main variables of the hydrolysis‐esterification process (temperature, methanol to oil molar ratio, and catalyst concentration), this work adopted the Central Composite Statistical Design to find out the combination of factors that lead to maximum biodiesel yield. It was observed that the Callera™ Trans L lipase presents a high catalytic activity, mainly in the initial reaction steps. The optimized variables for biodiesel synthesis were 35 °C methanol to oil molar ratio of 4.5:1, and 1.45 wt% of catalyst load, which allowed reaching a biodiesel yield of 96.9 % in 24 h of reaction.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.