Due to the increase in the price of the petroleum and the environmental concerns
about pollution coming from the car gases, biodiesel is becoming a developing
area of high concern (Marchetti, et al. 2007).Thus, looking for an alternative
way to develop a substitute of diesel is an imperious task for humans. The main
advantages of using this alternative fuel are its renewability, better quality of
exhaust gas emissions, its biodegradability and, given that all the organic carbon
present is photosynthetic in origin, it does not contribute to a net rise in the level
of carbon dioxide in the atmosphere if all of the energy inputs for the biodiesel
production are non-fossil-based, and consequently to the greenhouse effect
(Wang et al. 2006, Barnwal & Sharma, M.P. 2005.). Biodiesel fuel can be
produced from oils/fats through transesterification of triglycerides (TG) with
methanol. At present, most of the methods in transesterification use alkali
catalysts (Freedman et al. 1984). In the alkali-catalyzed method, however, free
fatty acids (FFA) react with a catalyst producing undesirable saponified
products. Therefore, this process needs sophisticated purification steps for