Biodiesel production using enzymatic transesterification - Current state and perspectives

Biodiesel has attracted considerable interest in recent years as an alternative, biodegradable and nonpolluting transportation fuel. Conventional alkaline process for biodiesel production are energy-consuming and generate undesirable by-products such as soaps, that make difficult the separation and purification of biodiesel. Particular attention has been dedicated to the use of lipases as biocatalysts for biodiesel production due to their favorable conversion rate obtained in gentle conditions and relatively simple downstream processing steps for the purification of biodiesel and by-products. However, comparatively to conventional chemical processes, the major obstacles for enzymatic production of biodiesel remain the cost of lipases, the relatively slower reaction rate and lipases inactivation caused by methanol and glycerol. This review evaluates the current status and perspectives for enzymatic biodiesel production and indicates the key operational variables that influence lipase activity and stability together with the technological solutions for industrial implementation of enzymatic process. (C) 2011 Elsevier Ltd. All rights reserved.