The enhanced use of diesel fuel and the strict emission norms for the protection of environment have necessitated finding sustainable alternative and relatively green fuels for compression ignition engines. This paper presents a brief review on the current status of biodiesel production and its performance and emission characteristics as compression ignition engine fuel. This study is based on the reports on biodiesel fuels published in the current literature by different researchers. Biodiesel can be produced from crude vegetable oil, non-edible oil, waste frying oil, animal tallow and also from algae by a chemical process called transesterification. Biodiesel is also called methyl or ethyl ester of the corresponding feed stocks from which it has been produced. Biodiesel is completely miscible with diesel oil, thus allowing the use of blends of mineral diesel and biodiesel in any percentage. Presently, biodiesel is blended with mineral diesel and used commercially as fuel in many countries. Biodiesel fueled CI engines perform more or less in the same way as that fueled with the mineral diesel. Exhaust emissions are significantly improved due the use of biodiesel or blends of biodiesel and mineral diesel. The oxides of nitrogen are found to be greater in exhaust in case of biodiesel compared to mineral diesel. But the higher viscosity of biodiesel also enhances the lubricating property. Biodiesel being an oxygenated fuel improves combustion.
Oleaginous microorganisms as sustainable feedstock for biodiesel production