Novel strategy for lipase-catalyzed synthesis of biodiesel usingblended alcohol as an acyl acceptor
Introduction
Biodiesels are defined as monoalkyl esters of long-chain fattyacids derived from vegetable oils or animal fats, for use in dieselengines [1,2]. Biodiesel can be used in any mixture with petroleumdiesel as it has very similar characteristics, but it has lower exhaustemissions. Biodiesel has better properties than those of petroleumdiesel in that it is renewable, biodegradable, non-toxic, and essen-tially free of sulfur and aromatics [3]. The use of biodiesel fuelhas the potential to reduce levels of pollutants and of potential orprobable carcinogens [4].The fundamental reaction in biodiesel production is the trans-esterification reaction, which can be catalyzed either chemicallyor enzymatically. Enzymatic transesterification has certain advan-tages over the chemical catalysis of transesterification, because itallows less energy intensity and easy recovery of glycerol [5–8].In the biodiesel production, methanol is most widely usedbecause of its economic feasibility and accessibility in mostcountries [9,10]. In addition, with a chemical catalyst, methanol