A Review on Application of Heterogeneous Catalyst in the Production of Biodiesel from Vegetable Oils

Abstract

Biodiesel has been considered as one of the interesting alternative and environmentally benign fuels. The development of environmental friendly heterogeneous catalyst for the esterification/transesterification process seems to be promising route and the reason why it is more preferred to conventional homogeneous and enzymatic catalyzed reactions is discussed. However, investigation on heterogeneous catalyst for biodiesel production is extensively carried out based on previous research studies. In order to reduce cost of biodiesel production, evaluation and characterization of heterogeneous catalytic materials before and after its preparation provide facts on the process that have significant impact on the desired activity and selectivity properties. This review study provides a comprehensive overview of common process techniques usually employ in producing biodiesel. Different materials that serve as sources of heterogeneous catalysts to transesterify oils or fats for production of biodiesel with emphasis on selection criteria of solid catalytic materials are also highlighted. The potential heterogeneous catalyst that could be derived from anthill, various methods of preparing solid catalysts, as well as reusability and leaching analysis are discussed in details.143 source for alternate fuel, which is sulphur content free, non-poisonous, renewable and biodegradable [6], this becomes imperative due to the fact that, the depletion of petroleum-based fuel has increased the price of diesel extraordinarily and also, greenhouse gas emission is of environmental concern [7].

Optimization of oil extraction from Leucaena leucocephala seed as an alternative low-grade feedstock for biodiesel production

“…Several sources of energy such as wood, coal, oil, petroleum and nuclear material, have been explored. However, overdependence on these conventional sources of energy has led to consequential ecological and environmental problems [1]. In general, fossil energy source is associated with depletion and emission of large volume of greenhouse gases, which are regarded as the main contributor to global warming.…”

Synthesis and characterization of anthill‐eggshell‐Ni‐Co mixed oxides composite catalyst for biodiesel production from waste frying oil

“…alternative catalysts. 1,2 Reusability and easy separation from product mixtures gives heterogeneous catalysts an edge over the others. Their application in the field of renewable energy to synthesize renewable and biodegradable fuel has become an area of research interest and much effort is needed to discover effective solid catalysts that can be synthesized easily from waste/abandoned materials.…”

“…A large number of heterogeneous catalysts for biodiesel production has been extensively investigated and reported in the literature. 2,3 The reported solid catalysts include pure metal oxide, 4 mixed metal oxide, 5 sulfated metal oxide, 6 biomass-derived catalyst, 7 naturally occurring material, 8 domestic waste, 9 and industrial waste. 10 There is an increasing interest in deriving heterogeneous catalysts from natural and waste materials for biodiesel production.…”

“…3, the peak represented at 2-theta equal to 32.3°, 37.45°, 54.0°, 64.3°, and 67.55° were attributed to the presence of CaO, while peaks detected at 2-theta equal to 18.1°, 34.1°, 47.25° and 50.6° were due to the presence of Ca(OH) 2 . The intense peaks at 18.1° and 34.1° for Ca(OH) 2 are an indication of exposure to moisture. 7 The XRD results implied that, due to the hydroscopic nature of CaO, the AENiCo catalyst contains a mixture of CaO and Ca(OH) 2 , the FAME yield increases from 42.56% at 40 °C to 89.23% at 70 °C.…”

“…In biodiesel production, three forms of catalyst, namely homogeneous, enzyme and heterogeneous, can be used. However, disadvantages associated with homogeneous catalysts (wastewater generation and inability to reuse the catalyst) and enzymes (exorbitant cost and easy deactivation) have motivated the search for alternative catalysts . Reusability and easy separation from product mixtures gives heterogeneous catalysts an edge over the others.…”