A review of the current state of biodiesel production using enzymatic transesterification

Abstract

Enzymatic biodiesel production has been investigated intensively, but is presently employed industrially only in a 20,000 tons/year pilot plant in China (Du et al. [2008] Appl Microbiol Technol 79(3):331-337). This review presents a critical analysis of the current status of research in this area and accentuates the main obstacles to the widespread use of enzymes for commercial biodiesel transesterification. Improved results for enzymatic catalysis are seen with respect to increased yield, reaction time and stability, but the performance and price of the enzymes need further advances for them to become attractive industrially for biodiesel production. Critical aspects such as mass transfer limitations, use of solvents and water activity are discussed together with process considerations and evaluation of possible reactor configurations, if industrial production with enzymes is to be carried out. Results of published studies on the productivity of enzymes are also presented and compared to the use of chemical catalysts.

Fatty acid ethyl esters production in aqueous phase by the oleaginous yeast Rhodosporidium toruloides

“…Biodiesel, a typical form of liquid biofuel, has attracted considerable interest in recent years (Demirbas, 2007;Fjerbaek et al, 2009;Liang et al, 2013). Biodiesel consists of monoalkyl esters of long-chain fatty acids with short-chain alcohols, primarily methanol and ethanol, resulting in fatty acid methyl esters (FAMEs) and fatty acid ethyl esters (FAEEs), respectively.…”

The challenge of biodiesel production from oil palm feedstock in Nigeria

“…Immobilization of lipase is the attachment of the enzyme onto a solid support or the confinement of the enzyme in a region of space (Jegannathan et al, 2008). Enzymes do not form soaps and can esterify both FFA and TG in one step without the need for subsequent washing step (Fjerbaek et al, 2009). Thus enzymes have an interesting prospect for industrial-scale production for reduction of production costs.…”

“…Thus enzymes have an interesting prospect for industrial-scale production for reduction of production costs. This is especially the case when using feeds high in FFA, especially second-generation raw materials like spent oils, animal fat and similar waste fractions, with high FFA and water content and large variation in raw material quality (Fjerbaek et al, 2009). …”

“…The pretreatment works by intruding the immobilization of enzymes through the enhancement of mass transfer by surface layer or intra-particle phase as well as shielding the enzyme vicinity from inhibiting alcohols and glycerol (Fjerbaek et al, 2009). Lipases hydrolyze TG (Saliset al, 2005) and are capable of catalyzing other unnatural reactions.…”

Biofuels Get in the Fast Lane: Developments in Plant Feedstock Production and Processing

“…Apart from the chemical catalysis, biodiesel production can be achieved using enzymatic (microbial lipases) transesterification of oils. This biocatalytic method of biodiesel production offers high selectivity, high purity product and fewer process steps compared to chemical catalysis but it needs improvements to reduce the high cost for industrial scale use and to speed up the reaction rate [7].…”