Method For Biodiesel Production Research Articles

Nanotechnology-based biodiesel: A comprehensive review on production, and utilization in diesel engine as a substitute of diesel fuel

As a sustainable replacement for fossil fuels, biodiesel is a game-changer in the energy sector. There is no strategy to minimize biodiesel's significance as a sustainable, clean fuel source in light of the increasing climate change and environmental sustainability concerns. Nevertheless, conventional biodiesel production methods often run into problems like inadequate conversion efficiency and inappropriate fuel properties, which impede their broad adoption. The revolutionary potential of nanotechnology to circumvent these limitations and revolutionize biodiesel consumption and production is explored in this review paper. There are new possibilities for improving biodiesel output and engine efficiency, thanks to nanotechnology, which can alter matter at the atomic and molecular levels. Using nano-catalysts, nano-emulsification processes, and nano-encapsulation procedures, researchers have made significant advances in improving biodiesel qualities such as stability, combustion efficiency, and viscosity. Through a comprehensive analysis of current literature and research data, this article elucidates the crucial role of nanotechnology in advancing biodiesel technology. By shedding light on the most current advancements, challenges, and potential future outcomes in nano-based biodiesel manufacturing and consumption, this review hopes to add to the growing corpus of knowledge in the field and inspire additional innovation. In conclusion, there is great hope for a sustainable energy future, increased economic growth, and reduced environmental impacts through the application of nanotechnology.

Comparative study of a two-step enzymatic process and conventional chemical methods for biodiesel production: Economic and environmental perspectives

The urgent need to address greenhouse gas (GHG) emissions underscores the significance of biodiesel as a key liquid biofuel. Compared to chemical biodiesel production, enzymatic technology offers a more sustainable alternative. This article presents a comparative study between a two-step enzymatic biodiesel production technology, already successfully industrialized, and conventional chemical technologies utilizing soybean oil (SBO) and waste cooking oil (WCO) as feedstock, respectively. The economic analysis demonstrates significant cost savings with the enzymatic process resulting in reductions of 16.33% and 36.54% for SBO and WCO, respectively. Enzymatic technology also exhibits substantial reductions in energy consumption, with a decrease of 86.8% and 60.2% for SBO and WCO, respectively. LCA findings indicate that enzymatic technology diminishes environmental impacts and GHG emissions are less than 78.86% and 63.05% for SBO and WCO, respectively. This study provides crucial insights for decision-makers, marking a significant paradigm shift in biodiesel production.

Magnesium Oxide (MgO) as a Sustainable Catalyst for Biodiesel Production from Waste Cooking Oil: A Comparative Study with KOH

The present study investigates the efficiency of magnesium oxide (MgO) as a heterogeneous catalyst in the production of biodiesel from waste cooking oil (WCO), putting an emphasis on its environmental benefits, cost-effectiveness, and operational efficacy. Through a series of experiments, we optimized the reaction conditions, including catalyst concentration, reaction temperature, and ethanol to WCO molar ratio, to achieve a high biodiesel yield. The results indicate that an optimal MgO concentration of 3 wt%, a reaction temperature of 65 °C, and a molar ratio of 9:1 result in the highest biodiesel production efficiency. Additionally, MgO demonstrated significant reusability without a decrease in performance, underscoring its economic and environmental advantages. Comparative analysis revealed that MgO outperforms conventional KOH catalysts in terms of yield, purity, and sustainability. Our study suggests future research directions, including the optimization of MgO preparation methods and the exploration of co-catalyst systems to further enhance biodiesel production from WCO. This research contributes to the development of sustainable biodiesel production methods, aligning with global energy and environmental goals.

Improvement of waste frying oil/cottonseed oil-based biodiesel properties by adjusting unsaturation and its effect on engine emission characteristics

Waste frying oil is a highly promising feedstock for biodiesel production due to its lower cost compared to refined vegetable oils. In this study, biodiesel was prepared by transesterification of mixed waste frying oil with dimethyl carbonate, utilizing immobilized recombinant lipase in tert-butanol as the medium. The activation energy (Ea) and pre-exponential factor (k0) were determined to be 73.8 kJ/mol and 1.62×106, respectively. Under optimal reaction conditions, the biodiesel yield can reach 88.5%. Subsequently, cottonseed oil was introduced into the feedstock to enhance the crystallization temperature of the product, which enables biodiesel production to meet the fuel property standards. The cold filter plugging point of biodiesel was reduced to 4.3 ℃. Ultimately, blending biodiesel with diesel significantly reduces smoke emissions from diesel engines, with the B80 blend demonstrating superior effectiveness. This study presents an efficient and cost-effective method for biodiesel production.

Zno Loaded Singgora Roof Tiles as Heterogeneous Catalyst for Waste Cooking Oil Biodiesel

This study aimed to utilize the waste cooking oil (WCO) into biodiesel using a novel waste Singgora roof tiles wet impregnated with zinc oxide (ZnO) as a heterogeneous catalyst. The motivation behind this choice stems from the non-recyclable nature of Singgora roof tiles and their potential applicability in biodiesel synthesis. The catalyst was characterized by X-ray Fluorescence (XRF) and scanning electron microscopy (SEM) with energy-dispersive X-ray diffractometer (EDX). A two-step transesterification method was employed to reduce the concentration of free fatty acids (FFA) in the WCO. The process started by treating the WCO with sulfuric acid (H2SO4) to diminish the levels of free fatty acid (FFA), followed by the utilization of the Singgora roof tiles catalyst in the subsequent step. A maximum yield of 96.96% biodiesel was obtained under the optimal conditions, which included a methanol-to- oil ratio of 12:1, a catalyst concentration of 1 wt.%, a reaction temperature of 65 °C, and a 2-hour reaction time. The quality of the biodiesel produced was analyzed according to biodiesel standards specified in the ASTM D6751, EN 14214, and AOCS, and were within the ranges. The study demonstrates the potential of using Singgora roof tiles as a heterogeneous catalyst in biodiesel production, offering a promising approach to repurposing non-recyclable materials and advancing sustainable biodiesel production methods.

Sustainable biodiesel production from waste olive oil: Utilizing olive pulp-derived catalysts for environmental and economic benefits

This paper introduces an environmentally and economically advantageous biodiesel production method using waste olive oil and pulp-derived catalysts. It tackles the critical issue of olive waste management by reusing discarded materials, reducing pollution, and minimizing landfill use. This sustainable approach preserves natural resources and reduces the carbon footprint associated with waste disposal. Olive pulp-derived catalysts offer a cost-effective and eco-friendly alternative to traditional catalysts, enhancing the economic viability of biodiesel production. Despite its low oil content, the waste olive pulp (WOP) is efficiently utilized for biodiesel production. The patent explores Sulfonated Carbon (SC) derived from dried olive pulp, serving as a robust acidic catalyst for transesterification. Characterization techniques comprising XRD, FTIR, and FESEM analyze SC properties. Biodiesel development optimization from waste olive oil (WOO) employs Response Surface Methodology (RSM), resulting in optimal conditions: a methanol-to-oil molar ratio of 15:1, a 60 °C reaction temperature, a 5-h transesterification time, and a 4% catalyst dose, yielding an impressive 94% biodiesel yield. The biodiesel's chemical structure is confirmed through analytical tools such as FT-IR, 1HNMR, and 13CNMR.In summary, this study highlights the potential of sulfonated carbon as a catalyst for sustainable biodiesel generation from waste olive oil. It offers a safe, efficient, and environmentally friendly alternative to traditional catalysts, delivering both environmental and economic benefits.

Green Catalysts for Sustainable Biodiesel Production from Waste Cooking Oil

Biodiesel manufacturing from waste cooking oil has emerged as a potential alternative in the search of sustainable energy. This process helps mitigate environmental pollution and reduces reliance on fossil fuels. This research examines the catalytic efficiency of environmentally friendly catalysts in this process, with a specific emphasis on catalysts based on enzymes. It assesses their effectiveness in terms of the production of biodiesel, the rate of the chemical reactions, cost efficiency, and their influence on the environment. Experimental evidence demonstrates that enzyme-based catalysts have enhanced catalytic activity, leading to an average biodiesel production of 90%, outperforming traditional catalysts such as solid acids, bases, and heterogeneous metal catalysts. Moreover, enzyme catalysts exhibit enhanced reaction rates due to their unique enzymatic activity and gentle reaction conditions. The cost study shows that the manufacturing costs for enzyme catalysts are competitive, with an average total cost of $800, which is equivalent to traditional catalysts. Environmental impact evaluation emphasizes the sustainability of enzyme catalysts by demonstrating their lower energy consumption, waste production, and greenhouse gas emissions compared to traditional alternatives. The results highlight the capacity of green catalysts, namely enzyme-based catalysts, to enhance sustainable biodiesel production methods, hence promoting a more eco-friendly and robust energy framework.

Chromatographic assessment of biodiesel production from Peganum harmala seed oil using environmentally benign nano-catalysts.

This work gives a comprehensive chromatographic assessment of biodiesel generation from plant seed oil using ecologically friendly nano-catalysts. Researchers all over the world are actively looking for new ways to satisfy the urgent need for clean and renewable energy sources. The resultant biodiesel was fully characterized utilizing modern techniques like scanning electron microscopy, energy diffraction X-ray and X-ray diffraction. The biodiesel gas chromatography/mass spectrometry analysis revealed four significant peaks of fatty acid methyl esters, indicating high-quality biodiesel production. Furthermore, the biodiesel fuel qualities were discovered to be comparable with international standards such as ASTM D-6571 and EN-14214. This indicates that the iron-modified clay nano-catalyst can be used as a catalyst for large-scale biodiesel production. This work is important because it could lead to the large-scale production of a novel, non-food feedstock. We may lessen our reliance on fossil fuels and contribute to a more sustainable and ecologically friendly energy future by leveraging the usage of biodiesel produced in this way. The chromatographic assessment of biodiesel production from non-edible seed oil using environmentally benign nano-catalysts holds significant promise in advancing sustainable and eco-friendly biodiesel production methods, contributing to a cleaner and more environmentally responsible energy sector.

A Review on Sustainable Approach for Production of Biodiesel from Waste Cooking Oil: A Case Study of Brunei Darussalam

Biofuels like biodiesel and bioethanol are the latest technologies to meet the rising energy demand and to replace depleting petroleum supplies. Biodiesel, which is made from vegetable oils, can be used to replace diesel fuel. Vegetable oils are a sustainable energy resource with a similar energy content to diesel fuel. In the proposed process, the main product from the reaction is biodiesel, whereas the by-products consist of glycerol and fertilizer. Biodiesel is mainly used in automotive diesel engines for various reasons, such as having a greater oxygen content, a higher cetane number, a higher viscosity, a lower aromatic content, and very little sulfur. These properties are essential in engine performance, combustion, and emissions. This review provides a comprehensive analysis of recent literature on biodiesel production methods from waste cooking oil, where the methods are grouped systematically and assessed. A decision table on process selection is provided to screen the most suitable technology for biodiesel production from waste cooking oil. The properties and application of potential products and by-products are also discussed. Finally, the case study of supplying biodiesel for B5 fuel in Brunei Darussalam is also provided.

Statistical optimization of ultrasound‐assisted biodiesel production from Moringa oleifera oil – waste cooking oil mixture using modified conch shell catalyst

AbstractBiodiesel is a potential alternative fuel that offers several environmental benefits and can be used in conventional engines. However, high feedstock cost poses a challenge for its commercial viability. This study focuses on producing biodiesel using waste cooking oil (WCO) and Moringa oleifera oil (MOO) as feedstock, with a specific emphasis on the use of modified conch shell as solid catalyst under ultrasonic conditions. Different mixtures of WCO and MOO were evaluated for their suitability in a two‐stage esterification transesterification process, and the acid value of the WCO‐MOO blend was reduced through an ultrasound‐assisted esterification process. Additionally, a calcium oxide‐based catalyst was developed from conch shells (CS) through calcination for 3 h at 900°C and further modified using water and methanol. The characterization studies confirm the successful development and modification of the CS catalyst and also demonstrates excellent catalytic activity. The ultrasound assisted transesterification process parameters were optimized using response surface methodology (RSM) based Box–Behnken design (BBD). By employing a catalyst loading of 5.8 wt%, methanol to esterified oil volumetric ratio of 0.37:1, and an ultrasonication time of 57 min, a maximum predicted methyl ester conversion of 94.7% was achieved. Therefore, this work provides valuable insights into the use of modified conch shell catalyst for biodiesel production from WCO and MOO mixtures thereby contributing to the advancement of cost‐effective and environmentally friendly biodiesel production methods.

A mini-review of biodiesel production methods and its properties

Fatty acid esters (FAEs) attract attention worldwide due to their environmental friendliness, renewable nature and the possibility of their use as additives to traditional diesel fuel. Current energy crisis in Ukraine can be solved only under the condition of rational use of all energy sources and search for alternative ones. Among them, the technologies involving FAEs play an important role. The paper discusses various options for the transesterification process of FAEs: non-catalytic and catalytic ones. Information is provided about different types of catalysis. Different raw materials for the production of FAEs of various origins are overviewed. The characteristics of existing installations and methods of the FAE production are given. The main advantages and disadvantages of the above-mentioned aspects of the FAE production are analyzed. Comparison of the physicochemical characteristics of FAEs obtained by different methods is made. Recommendations are given to partially overcome the existing fuel crisis in Ukraine with the help of biofuel production.

Toward Efficient Continuous Production of Biodiesel from Brown Grease

An increase in energy consumption and the extended use of nonrenewable fossil fuels raises the need to develop alternative fuels as an energy supply that can protect the environment from unwanted emissions of pollutants. One alternative renewable fuel is biodiesel. Currently, most biodiesel feed sources are edible oils, but using them leads to the dilution of global food sources. The present study aims to find an effective method of biodiesel production using food industry fatty wastes called brown grease (BG). BG contains fats, mainly linoleic and oleic free fatty acids (FFAs), that can serve as raw materials for biodiesel production using esterification reactions. The esterification and transesterification reactions for biodiesel production were studied using commercial FFAs, commercial glyceryl trilinoleate (trilinolein), soybean oil, and BG. The reactions were carried out under ultrasonic activation using BF3 and AlCl3 Lewis acids as catalysts in both free and immobilized forms when immobilization was performed in silica matrices using the sol-gel synthesis route. Biodiesel production was examined in batch and continuous flow reactors. The BF3 catalyst was more efficient at the initial stages of the continuous operation, reaching a maximum conversion of 90%, with a gradual decrease in efficiency after 15 h of the process. The AlCl3 catalyst showed better stability, reaching maximum yields of 97% and maintaining efficiency until the end of the experiment. The proposed method offers an efficient and easy way to produce biodiesel from a variety of lipids sources, including fatty wastes (BG).

One-Pot Synthesis of Biodiesel from Acid Oil Using a Switchable Solvent, 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU), as a Bifunctional Catalyst

Biodiesel is a promising alternative to petrodiesel, but its production from acid oils retains several technical challenges. Therefore, this study developed a new approach involving 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-catalyzed one-pot reaction (simultaneous esterification-transesterification) to produce biodiesel with enhanced reaction efficiency. The reaction was performed under water removal conditions and optimized using response surface methodology to maximize the biodiesel yield. The optimal conditions for the one-pot reaction had a reaction time of 2.73 h, temperature of 143°C, methanol:oil molar ratio of 24.3 : 1, and DBU loading of 30.1%. Under the optimal conditions, maximum total biodiesel of 97.1% was obtained. DBU could be repeatedly used for at least 5 cycles to yield over 91% biodiesel. This study suggests that DBU efficiently catalyzed esterification and transesterification simultaneously and the DBU-catalyzed one-pot reaction is an efficient method for biodiesel production from high-free-fatty acid oils.

Enabling Catalysts for Biodiesel Production via Transesterification

With the rapid development of industry and the increasing demand for transportation, traditional sources of energy have been excessively consumed. Biodiesel as an alternative energy source has become a research focus. The most common method for biodiesel production is transesterification, in which lipid and low carbon alcohol are commonly used as raw materials, in the presence of a catalyst. In the process of transesterification, the performance of the catalyst is the key factor of the biodiesel yield. This paper reviews the recent research progress on homogeneous and heterogeneous catalysts in biodiesel production. The advantages and disadvantages of current homogeneous acid catalysts and homogeneous base catalysts are discussed, and heteropolyacid heterogeneous catalysts and biomass-derived base catalysts are described. The applications of the homogeneous and heterogeneous catalyst derivatives ionic liquids/deep eutectic solvents and nanocatalysts/magnetic catalysts in biodiesel production are reviewed. The mechanism and economic cost of current homogeneous acid catalysts and homogeneous base catalysts are also analyzed. The unique advantages of each type of catalyst are compared to better understand the microscopic details behind biodiesel. Finally, some challenges of current biodiesel catalysts are summarized, and future research directions are presented. This review will provide general and in-depth knowledge on the achievements, directions, and research priorities in developing novel homogeneous/heterogeneous catalysts for the green and cost-effective production of biodiesel.

Biodiesel Production through Electrolysis Using an Ionic Liquid, 1-Ethyl-3-Methylimidazolium Chloride as a Supporting Electrolyte

Electrolysis is a promising approach for biodiesel production. However, low electrical conductivity of a reaction mixture results in a low reaction rate. Thus, this study developed a novel catalyst-free electrolysis process using an ionic liquid as a supporting electrolyte for biodiesel production. Various ionic liquids were assessed, and 1-ethyl-3-methylimidazolium chloride ([Emim]Cl) exhibited the highest electrical conductivity (4.59 mS/cm) and the best electrolytic performance for transesterification. Electrolysis in the presence of [Emim]Cl was subsequently optimized using response surface methodology to maximize biodiesel yield. A maximum biodiesel yield of 97.76% was obtained under the following optimal reaction conditions: electrolysis voltage, 19.42 V; [Emim]Cl amount, 4.43% ( w / w ); water content, 1.62% ( w / w ); methanol to oil molar ratio, 26.38 : 1; and reaction time, 1 h. Notably, [Emim]Cl could be efficiently reused for at least three cycles with a corresponding biodiesel yield of 94.81%. Moreover, the properties of the synthesized biodiesel complied with EN and ASTM standards. The findings of this study indicate that catalyst-free electrolysis using [Emim]Cl as a supporting electrolyte is an eco-friendly and efficient method for biodiesel production.

Integrated Approach to Spent Coffee Grounds Valorization in Biodiesel Biorefinery

With the increasing consumption of coffee beverages, an increased amount of food waste—spent coffee grounds (SCG)—is generated and disposed into landfills or combusted in incinerators. SCG are characterized as a highly polluting substance with partial toxicity due to the presence of caffeine, tannins, and polyphenols. It also contains 15% of oil on average, and its potential for biodiesel production is thus considerable. The aim of the presented work is to evaluate the possibility and technical potential of biodiesel production from the SCG oil (SCGO) by esterification and transesterification reaction. According to the characterization of the studied SCGO, this stream must be adjusted and purified to be utilized in the existing biodiesel production plant. Fatty acids (FA) represent 85.85% of the SCGO, with two dominant FAs—linoleic and palmitic acids. The necessity of removal and disposal of unsaponifiable matter, which accounts for 15% of the SCGO content, must be highlighted when producing biodiesel from the SCG. The objective of this research was the comparison of different biodiesel production processes, where a two-step transesterification process has been identified as the most successful method for biodiesel production from the SCGO with the highest ester content of 89.62% and the lowest content of unsaponifiable and unidentified matter in the final product. The novelty of the analyses is a characterization of the d unsaponifiable matter present in the SCGO, and the article highlights the importance of progression to be considered when evaluating the technical potential of the SCG biodiesel production integrated into a biorefinery. Nevertheless, the SCG biodiesel can contribute to fulfilling the mandatory share of advanced biofuel in the fuel energy mix given by national legislation and contribution to the circular economy approach of biorefineries.

Transesterification of Algae Oil and Little Amount of Waste Cooking Oil Blend at Low Temperature in the Presence of NaOH

The present study describes the single-step transesterification method of biodiesel production from high free fatty acid (FFA) waste cooking oil blended with algae oil using a homogeneous base catalyst. Due to high FFA contents, two step transesterification is needed to convert oil into biodiesel and therefore the high FFA content of waste cooking oil is decreased by blending it with low FFA content algae oil, which would further lead only to single step transesterification of low FFA oil. The design and optimization studies were conducted using Response Surface Methodology (RSM). The box-Behnken design technique is applied to optimize the three process parameters, i.e., catalyst concentration (0–2 wt%), methanol concentration (v/v) (20–60%) and reaction time (60–180 min) at a uniform reaction temperature of 50 °C. The result of the current study indicates that an effective biodiesel yield of 92% can be obtained at the optimized condition of catalyst concentration of 1.5% (w/w), methanol/oil ratio of 21:1 and reaction time of 110 min at a constant reaction temperature of 50 °C. This analysis clearly shows that this study can resolve the storage problem of high FFA oils from different feedstock and RSM can be successfully used to model the reaction to maximize the biodiesel yield.

Multifarious extraction methodologies for ameliorating lipid recovery from algae

Amongst the current alternatives, algae were proven to be a promising source of biofuel, which is renewable and capable of meeting world demand for transportation fuels. However, a suitable lipid extraction method that efficiently releases the lipids from different algal strains remains a bottleneck. The multifarious pretreatment methods are prevalent in this field of lipid extraction, and therefore, this article has critically reviewed the various lipid extraction methods for ameliorating the lipid yield from algae, irrespective of the strains/species. Physical, mechanical, and chemical are the different types of pretreatment methods. In this review, methodologies such as homogenization, sonication, Soxhlet extraction, microwave treatment, and bead-beating, have been studied in detail and are the most commonly used methods for lipid extraction. Specific advanced/emerging processes such as supercritical CO2 extraction, ionic liquid, and CO2 switchable solvent-based algal lipid extraction are yet to be demonstrated at pilot-scale, though promising. The extraction of lipids has to be financially conducive, environmentally sustainable, and industrially applicable for further conversion into biodiesel. Hence, this paper discusses variable pretreatment for lipid extraction and imparts a comparative analysis to elect an efficient, economically sound lipid extraction method for pilot-scale biodiesel production.

Phycoremediation of Arsenic and biodiesel production using green microalgae Coelastrella sp. M60 – an integrated approach

Arsenic (As) contamination is a wide-spread environmental threat, representing serious environmental as well as health-related problems. The present study focuses on Arsenic abatement using phycoremediation and nanoparticle mediated adsorption, proposing an effective and affordable As detoxification with scale-up options. A series of experimental analyses such as Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDX), Ion Exchange Chromatography (IC) and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), performed, inferred that the microalgal isolate Coelastrella sp. M60 is capable of a 66.26 ± 1.36, 49.19 ± 0.103 and 19.20 ± 1.17 % adsorption of 1, 2, and 3 ppm As V, respectively, at the end of 12 h (analyzed via ICP-OES). Post treatment with TiO2 resulted in increased adsorption %, implying the ability of direct As (III) adsorption by the nanoparticles. Further, the As exposed biomass was subjected to lipid extraction and FAME preparation using four different methods for biodiesel production. The obtained FAME was subjected to biodiesel quality parameters analyses, whose results implied that the As exposed M60 cells demonstrated increased lipid content (1.25 folds higher) and improved FAME production (62.501 ± 0.979 mg/g biomass), with a 96.70 % of MUFA, yielding good quality biodiesel obtained via a novel, rapid and economical, nanoparticle-pretreated direct transesterification method. Henceforth, the study has unveiled a simple, effective approach for abatement of inorganic As using the microalgae Coelastrella sp. M60, along with the production of good quality biodiesel, by recycling the biomass, previously employed for the bioremediation of As, as a feedstock thus demonstrating a zero waste concept.

Sustainable biodiesel production via catalytic and non-catalytic transesterification of feedstock materials – A review

As fossil fuels have been depleting, there is a need to develop an alternative fuel to meet the possible future energy shortage. Biodiesel is one of the most promising resources that has recently emerged. A thorough review has been conducted in this paper to highlight various aspects of the biodiesel, such as biodiesel feedstocks, production methods, properties and qualities of biodiesel, problems and potential solutions of using vegetable oil, advantages and disadvantages of biodiesel, the economic viability and finally the future of biodiesel. Various feedstock materials have been explored, such as non-edible oils like Jatropha curcas and Calophyllum inophyllum and, more recently, microalgae and genetically engineered plants such as poplar and switchgrass. Various production methods such as dilution, pyrolysis, microemulsion, and transesterification have been discussed, highlighting their merits and demerits. Out of these methods, the transesterification process is a better option for production and lowering production costs. The most sustainable way to produce biodiesel is via catalytic and non-catalytic transesterification processes. Various types of catalysts such as homogeneous & heterogeneous acid/basic, mixed, and enzymatic have been investigated to compare their catalytic potential in transesterification.