Recent Advances in Heterogeneous Catalysts for Biodiesel Production

Abstract

Heterogeneous catalysts plays a significant role in the production of biodiesel as they have many advantages over other catalysts. Heterogeneous catalysis are noncorrosive, requires mild environmental conditions with fewer disposal problems. The easy separation of product from the liquid is mainly achieved by the reusability as the catalyst settles at faster rate. The use of this catalyst is widely used for biodiesel production due to higher activity, selectivity and longer lifetime of the catalyst. The heterogeneous catalyst reduces the overall production cost of biodiesel making it competitive with other petroleumbased diesel fuels. Recently, heterogeneous catalysts derived from nanomaterials have gained attention for biodiesel synthesis. Nanocatalyst characteristics, such as high catalytic activities and high specific surface area have helped overcome some limitations on heterogeneous catalysts for their applications in biodiesel production from biomass. This paper discusses the latest advances in research and development related with heterogeneous nanocatalysts. The use of nanocatalysts such as ferrous doped zinc oxide, copper doped zinc oxide and manganese doped zinc oxide for biodiesel production are discussed and compared.

Recent progress for hydrogen production from ammonia and hydrous hydrazine decomposition: A review on heterogeneous catalysts

“…Thus, heterogeneous catalysts are, mostly, in the solid state while the reactant mixture is either liquid or gas, in contrast with homogeneous catalysts that exist in the same phase with the mixture. Heterogeneous catalysts have the ability to regenerate, separate easily from the products, shaped into different geometries and give high rates [45]. Table 1 summarises the most effective heterogeneous catalysts utilized for the decomposition of ammonia.…”

Advances in Metal Oxide‐based Nanocatalysts for Biodiesel Production: A Review

“…The stirring speed of transesterification reaction enhances the percentage yield of biodiesel. Actually, it favours the maximum mixing of the contents in minimum time and also influences on the reaction kinetics 19, 96–98, 102, 104, 105. Tab.…”

“…Moisture content is a critical variable when using biomass as an energy source because it greatly impacts the conversion efficiency and heating value. High moisture content also causes logistical challenges since it makes materials more likely to degrade, which lowers the energy and cost balances [19,94,96,[99][100][101][102].…”

“…This system is adopted for its cost-effectiveness, pollution reduction, large-scale applicability, and sustainability [13][14][15][16][17][18]. Metal oxide based nanocatalysts, such as single metal oxides, derivatives of transition metal oxides, supported alkali and alkaline earth metal oxides, doped heterogeneous catalysts, and mixed metal oxides are used in the conversion of triglycerides into biodiesel [19]. Some common metal oxide based nanocatalysts such as CaO, MgO, Fe 3 O 4 , Mn doped ZrO 2 , impregnated MgO, CuO, and NiO on zeolite 4A, CeO 2 /CaO and KF/CaO-Fe 3 O 4 were successfully utilized in the transesterification of soybean oil, waste sheep oils, stillingia oil, and algal biomass (Chlorella vulgaris) [20][21][22][23][24][25].…”

Prospects of Catalysis for Process Sustainability of Eco-Green Biodiesel Synthesis via Transesterification: A State-Of-The-Art Review

“…Hence, the modification of a homogeneous catalyst is easy, whereas a heterogeneous catalyst modification is difficult. Homogeneous catalysts are less thermostable while heterogeneous catalysts have high thermal stability [52,53].…”