Insight into the Recent Advances in Sustainable Biodiesel Production by Catalytic Conversion of Vegetable Oils: Current Trends, Challenges, and Prospects
Eslam A. Mohamed, Mohamed A. Betiha, Nabel A. Negm
Abstract
Recently, numerous advances were reported in the creation of efficient and low-cost heterogeneous catalysts for the transesterification reactions of triglyceride molecules to decrease the overall cost of biofuel production. The heterocatalytic transesterification process has been recognized to be the most emerging approach in biodiesel synthesis as a result of its ease of use and low price. The unique characteristics of seven different kinds of heterogeneous catalysts, containing heteropolyacid, zeolite-based catalyst, layered-double-hydroxide-based catalyst, graphene, graphene oxide, activated carbon, biomass and non-biomass waste materials, and finally metal- and metal-oxide-based catalysts that are frequently employed in current biodiesel research, have undergone extensive studies. The emphasis is on multipurpose catalysts, which have high catalytic efficiency and low production cost because they create biofuel that is more applicable, effective, and eco-friendly. This review highlighted significant factors affecting the efficiency of heterogeneous catalysts, discussed the reaction parameters that affect biofuel production from various vegetable oil feedstocks, also mentioned the reaction mechanism of biodiesel production using heterogeneous catalysts, and last debated process opportunities and challenges that could stimulate future exploration.