Review on direct transesterification method using recent technologies

Nowadays the research is focused on microalgae oil for biodiesel production because of high yield as compared to vegetable plant oil and it fixes carbon dioxide from atmosphere. It is a third-generation biofuel that can easily replace diesel which will deplete in couple of decades and can be used in diesel engine without any modification simultaneously cutting down the engine emissions. The biodiesel production from microalgae is a complex process which includes harvesting, drying, cell disruption, lipid extraction and biodiesel production. However, using direct in-situ transesterification these steps are reduced, and biodiesel production get simplified. Here in this wet algal biomass directly transesterified using alcohol, catalyst and solvents thus eliminating the drying and oil extraction process. This paper reviews the different methods used for direct transesterification in order to reduce the cost of production and increase the biodiesel yield. For cell different techniques are studied and analyzed the best technique from literature review.