Biodiesel Production Using Solid Acid Catalysts Based on Metal Oxides

Abstract

The development of solid acid catalysts, especially based on metal oxides and different magnetic nanoparticles, gained much awareness recently as a result of the development of different nano-based materials. Solid acid catalysts based on metal oxides are promising for the (trans)esterification reactions of different oils and waste materials for biodiesel production. This review gives a brief overview of recent developments in various solid acid catalysts based on different metal oxides, such as zirconia, zinc, titanium, iron, tungsten, and magnetic materials, where the catalysts are optimized for various reaction parameters, such as the amount of catalyst, molar ratio of oil to alcohol, reaction time, and temperature. Furthermore, yields and conversions for biodiesel production are compared. Such metal-oxide-based solid acid catalysts provide more sustainable, green, and easy-separation synthesis routes with high catalytic activity and reusability than traditionally used catalysts.

Nanoferrites heterogeneous catalysts for biodiesel production from soybean and canola oil: a review

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Copper molybdate synthesized by sonochemistry route at room temperature as an efficient solid catalyst for esterification of oleic acid

“…In the case of Brønsted acids, these have greater activity in the esterification reactions, while Lewis acids are more efficient in transesterification [14] . These referred groups interact efficiently with polar groups of the substrate molecules (oils, fats and fatty acids), conducting the esterification and transesterification reactions under a lower energy barrier [15] . Besides, the surface area, pore diameter and volume, surface energy, and particle size of solid catalysts positively influence these materials' catalytic properties [16] .…”

Microwave-assisted Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones Using Acid-Functionalized Mesoporous Polymer

“…The increase in catalyst amount initially increased the yield of the DHPM, attributed to the increase in the catalyst active sites. 34,35 The highest yield of 98 % was obtained when the catalyst amount was increased to 6 wt. %, however, further increase in the catalyst amount led to the depletion of DHPMs yield as large amount of catalyst makes the reaction mixture more viscous, hence inhibits the interaction between the reactants and catalyst active sites.…”