Review of Recent Developments in Solid Acid, Base, and Enzyme Catalysts (Heterogeneous) for Biodiesel Production via Transesterification

Development of new and effective solid catalysts (solid acid base to immobilized enzyme) is necessary for renewable and green energy production. The various choices of heterogeneous solid catalysis were reported recently, and the specific research outcomes of trans-esterification on heterogeneous catalysis are discussed in the present article. The studies on biodiesel production are mainly focused on the following aspects: (i) examining the appropriate oil source, (ii) establishing the adequate alcohol to oil molar ratio, and (iii) evaluating the available solid acid catalysts, solid base catalysts, and lipase immobilized enzyme catalysts. Although homogeneous catalysis are superior in terms of reaction rate compared to heterogeneous catalysis, the focus of research on development of solid catalysts for heterogeneous catalytic transesterification is directed from the point of easy process and possible adoption for large scale production. The scope of this presentation is to examine these aspects in detail and to provide a comprehensive outlook on the aspects mentioned.