Method For Biodiesel Production Research Articles

Optimization of microwave-assisted biodiesel production using response surface methodology

Energy stands as the fuel of the human activities, and with finite fossil fuels, biodiesel has become a promising, eco-friendly alternative. Microwave technology is emerging as one of the most efficient biodiesel production methods. The primary goal of this work is to optimize the microwave-assisted production of biodiesel and improve its productivity using response surface methodology. A modified microwave oven with built-in stirring system and temperature measurement significantly reduces the reaction time compared to traditional thermoelectric heating. Numerous factors impact microwave-assisted biodiesel production, encompassing catalyst type and concentration, microwave power, reaction temperature, alcohol type, alcohol-to-oil molar ratio, water content, and stirring rate. Hence, acquiring a comprehensive understanding of how these variables affect the biodiesel production becomes imperative. Response surface methodology was utilized to improve the biodiesel microwave-assisted production yield of sunflower oil involving ethanol as alcohol and NaOH as catalyst. The impact of the ethanol-to-oil ratio, the catalyst amount and the reaction temperature on biodiesel production yield was investigated. Results demonstrated that the temperature had the most significant impact on biodiesel production, with an optimal temperature of 70 °C. The highest biodiesel yield, of 98.4%, was obtained at an alcohol-to-oil ratio of 6:1 and 2% by mass of sodium hydroxide.

Production of Biodiesel from Industrial Sludge: Recent Progress, Challenges, Perspective

This study investigated biodiesel production from industrial sludge, focusing on the feasibility and sustainability of converting waste materials into renewable energy sources. This study combines a comparative analysis of various sludge-based biodiesel production methods, highlighting both their environmental benefits and economic potential. Utilizing physical, chemical, and biological pre-treatments, this study optimizes biodiesel yield while assessing the impact of each method on the overall production efficiency. Key findings revealed that industrial sludge provides a viable feedstock, contributes to waste reduction, and reduces greenhouse gas emissions. The novel contributions of this study include a detailed economic assessment of biodiesel production from sludge and a comprehensive environmental impact evaluation that quantifies the potential sustainability benefits. Limitations related to scale-up processes are identified, and solutions to overcome these issues are discussed to improve industrial feasibility. Furthermore, the integration of sludge-based biodiesel production with other renewable energy systems has been explored as a future avenue to enhance energy efficiency and sustainability. This research contributes to a significant scientific niche by addressing scalability challenges and proposing future perspectives for sustainable biodiesel production from industrial waste.

Transforming wastewater-derived algae biodiesel with ammonium hydroxide emulsion for enhanced energy efficiency and emission reduction

The growing demand for sustainable energy has prompted a search for alternative fuels, with microalgae-based biodiesel emerging as a promising option. However, improving its energy efficiency and minimizing environmental impacts remain key challenges. This study presents a novel approach by integrating wastewater-derived algae cultivation with ammonium hydroxide emulsion to enhance biodiesel performance. Chlorella vulgaris microalgae were grown in a medium of diluted human urine, where nutrient removal efficiency was evaluated, and biooil was extracted via solvent extraction. The resulting biodiesel was analyzed for elemental, chemical, and physicochemical properties. A 30 % blend of Chlorella vulgaris algae biodiesel (CVAB) with normal diesel fuel (NDF) was prepared. To further boost energy efficiency and emissions performance, ammonium hydroxide emulsion was added at concentrations of 5 % and 10 %. Results confirmed that wastewater-sourced algae cultivation is a viable method for sustainable biodiesel production. While CVAB's combustion characteristics were similar to NDF's, it exhibited a 7 % decrease in brake thermal efficiency and a 5 % increase in nitrogen oxide emissions. The addition of ammonium hydroxide emulsion notably improved both energy efficiency and emission profiles. This study highlights a breakthrough in using ammonium hydroxide emulsion to enhance algae biodiesel, making it a more competitive alternative to fossil fuels. Economically, this approach offers a dual advantage: utilizing low-cost wastewater for biodiesel production while improving fuel performance and reducing emissions.

A CHEMCAD Software Design Approach for Non-Conventional Biodiesel Production Using Methyl Acetate as Feedstock

Biodiesel is a sustainable and renewable fuel generated from renewable resources, including vegetable oil or animal fats. It is thought to be a non-toxic fuel that degrades gradually and causes no harm to the environment. In the present study, a non-conventional supercritical method for industrial biodiesel production is investigated. The non-conventional method refers to a single-step interesterification reaction between triglycerides and methyl acetate resulting in methyl esters of fatty acids and triacetin as a secondary product. Process flowsheet modeling, using CHEMCAD chemical engineering software, was used as an investigation tool. The production capacity was set to 25,000 kg/h biodiesel. Methyl acetate requested in the biodiesel production is produced from methanol esterification with acetic acid using an intensified reactive distillation unit. Methanol, in turn, is obtained using synthetic gas derived from biomass as a raw material, the process representing a new method at the industrial level to solve problems related to the energy that is required, storage and disposal of residual materials, and pollution through the release of pollutants into the air. The methanol synthesis process is similar to the one based on natural gas, consisting of three main steps, namely: (i) synthesis gas production, followed by (ii) methanol production, and (iii) methanol purification. Acetic acid is an essential chemical product, generated in the proposed approach by a sustainable method with low energy consumption and low air emissions, more exactly methanol carbonylation. All the processes previously mentioned: (i) biodiesel production, (ii) methyl acetate production, (iii) acetic acid production, and (iv) methanol production were modeled and simulated, leading to the desired biodiesel productivity (e.g., 25,000 kg/h) with the obtained purity being higher than 99%. Relevant discussions regarding the design assumptions used, the simulation and validation results, as well as other technical issues (i.e., electricity and thermal energy consumption) for the system being simulated, are provided, leading to the conclusion that the proposed route is well suited for the desired application and can deliver significant results. The simulation outcomes have provided confidence in the feasibility and effectiveness of the chosen process design, making it a viable option for further development and implementation.

Application of green SC-CO2 oil extraction method with a new green catalyst from luffa fruit for biodiesel production from Persian Lilac-Melia Azedarach fruits

Considering the importance of finding new suitable and environmentally friend resources and methods for biodiesel production, the present work has investigated Supercritical Carbon dioxide (SC-CO2) extraction as a new highly efficient and green oil extraction method for oil production from Persian Lilac-Melia Azedarach (PLMA) fruits and its conversion into biodiesel using a new green catalyst. The effects of pressure (22–30 MPa), temperature (40–80 °C) and extraction time (0–240 min) on supercritical carbon dioxide extraction were investigated and the results were compared with ultrasonic probe and Soxhlet extraction methods. The findings indicated that the total oil production rose with higher pressure and temperature, but a decrease was noticed at elevated temperatures. The most effective parameters for extracting PLMA oil were determined to be a pressure of 30 MPa, a temperature of 40 °C, and an extraction time of 180 min. The oil yield obtained by SC-CO2 extraction method was 32 % while it was 30 % and 28 % for Ultrasonic probe and Soxhlet extraction methods, respectively. Finally, a new green catalyst was synthesized from sponge of luffa plant to convert the extracted oil into a green biodiesel. In the future outlook, the efficient oil extraction method including modified SC-CO2 will be proposed for oil extraction from Melia azedarach fruits and the using of the modified catalyst for converting the oil to biodiesel.

Catalytic Potential of Singgora Roof Tiles in Transesterification for Sustainable Biodiesel

The study centred around the uitilization of Singgora roof tiles as a heterogeneous catalyst in the production of biodiesel via the transesterification process. The motivation behind this choice stems from the non-recyclable nature of Singgora roof tiles and their potential applicability in biodiesel synthesis. To enhance the catalytic properties, zinc oxide (ZnO) is incorporated using the wet impregnation technique during catalyst preparation. The catalyst was characterized by XRF and SEM-EDX. A two-step transesterification method is employed to mitigate the levels of free fatty acid (FFA) in waste cooking oil (WCO). The initial step involves treating the WCO with sulfuric acid (H2SO4) to reduce FFA. Subsequently, the Singgora roof tiles catalyst is utilized in the second step. A high yield of FAMEs, specifically 96.96%, was achieved 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 reaction time of 2 hours. The quality of the biodiesel produced was analyzed according to biodiesel standards such as ASTM D6751, EN 14214, and AOCS, and it met all the required standards. 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.

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.

Utilising Polyester and Steel Slag‐Derived Metal/Carbon Composites as Catalysts in Biodiesel Production

Synthetic textiles such as polyesters are essential for daily life. However, large‐scale production generates large amounts of waste. This study introduces a new approach for valorising polyester textile waste (PTW) by transforming it into a catalyst for biodiesel production via pyrolysis. Specifically, a metal/carbon composite (PTW + steel slag [SS] composite—PSC) with enhanced catalytic properties was prepared by pyrolysing PTW with SS. The alkaline metals in SS facilitate the carbonisation of PTW via decarboxylation, resulting in a PSC rich in carbon, iron, and alkaline compounds. This composite featured mesopores that were larger than the micropores (MPs) typically found in PTW char. The use of porous material (silica) in thermally induced transesterification has been proven to be an efficient method for biodiesel production, achieving a yield of 97.20 wt.% in 1 min (faster than the 93.82 wt.% yields in 60 min observed from conventional alkali‐catalysed transesterification). However, the high reaction temperature (≥ 360°C) poses economic/technical challenges. To overcome this, PSC has been employed as a catalyst in thermally induced transesterification, leveraging its mesoporous structure and high alkaline content, particularly calcium oxide. The PSC achieved a biodiesel yield of 98.10 wt.% at a markedly lower reaction temperature of 120°C within 1 min. This performance was not attainable using silica or PTW char under similar conversion conditions. These findings highlight the potential of PSC produced through the pyrolysis of PTW and SS as effective catalysts for biodiesel production. This process is a promising strategy for converting waste into valuable resources and mitigating the environmental impacts associated with polyester waste.

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.