Transesterification of jatropha curcas l. seed oil to biodiesel: an update

Jatropha curcas L. seed oil has been identified as one of the potential source of feedstock for biodiesel production which is a renewable energy. The oil cannot be used directly as fuel due to its high viscosity and therefore has to be processed to lower the viscosity. Transesterification is the best process adopted by many of the researchers for processing jatropha oil into biodiesel. The current review is intended to look at these different processes used by many of the researchers; considering the conditions that optimized the process used, comparing the yield and quality of the biodiesel produced with the standard properties prescribed by American Society of Testing and Materials (ASTM) standard. The use of subcritical hydrolysis or addition of micro amount of catalyst employed with supercritical transesterification has shown to reduce drastically the high reactant molar ratio, temperature and pressure associated with supercritical transesterification process. Heterogeneous transesterification of high free fatty acid (FFA) content jatropha oil assisted with ultrasonic irradiation reduces the reaction time and increase yield of biodiesel. All the transesterification processes used by many of the researchers gives high yield of biodiesel from jatropha oil or seed at various reaction conditions and the fuel properties falls within the ASTM standard specification. There is a need to carry out research on the economic analysis of the best processes that gives high yield at better reaction condition which can be employed in the production of biodiesel from Jatropha curcas L. seed oil at industrial scale.