Sustainable biodiesel production via catalytic and non-catalytic transesterification of feedstock materials – A review

Abstract

As fossil fuels have been depleting, there is a need to develop an alternative fuel to meet the possible future energy shortage. Biodiesel is one of the most promising resources that has recently emerged. A thorough review has been conducted in this paper to highlight various aspects of the biodiesel, such as biodiesel feedstocks, production methods, properties and qualities of biodiesel, problems and potential solutions of using vegetable oil, advantages and disadvantages of biodiesel, the economic viability and finally the future of biodiesel. Various feedstock materials have been explored, such as non-edible oils like Jatropha curcas and Calophyllum inophyllum and, more recently, microalgae and genetically engineered plants such as poplar and switchgrass. Various production methods such as dilution, pyrolysis, microemulsion, and transesterification have been discussed, highlighting their merits and demerits. Out of these methods, the transesterification process is a better option for production and lowering production costs. The most sustainable way to produce biodiesel is via catalytic and non-catalytic transesterification processes. Various types of catalysts such as homogeneous & heterogeneous acid/basic, mixed, and enzymatic have been investigated to compare their catalytic potential in transesterification.