Methyl Ester Yield Research Articles

Integrating life cycle assessment and characterisation techniques: A case study of biodiesel production utilising waste Prunus Armeniaca seeds (PAS) and a novel catalyst

Prunus Armeniaca seed (PAS) oil was utilised as a waste biomass feedstock for biodiesel production via a novel catalytic system (SrO–La2O3) based on different stoichiometric ratios. The catalysts have been characterised and followed by a parametric analysis to optimise catalyst results. The catalyst with a stoichiometric ratio of Sr: La-8 (Sr–La–C) using parametric analysis showed an optimum yield of methyl esters is 97.28% at 65 °C, reaction time 75 min, catalyst loading 3 wt% and methanol to oil molar ratio of 9. The optimum catalyst was tested using various oil feedstocks such as waste cooking oil, sunflower oil, PAS oil, date seed oil and animal fat. The life cycle assessment was performed to evaluate the environmental impacts of biodiesel production utilising waste PAS, considering 1000 kg of biodiesel produced as 1 functional unit. The recorded results showed the cumulative abiotic depletion of fossil resources over the entire biodiesel production process as 22,920 MJ, global warming potential as 1150 kg CO2 equivalent, acidification potential as 4.89 kg SO2 equivalent and eutrophication potential as 0.2 kg PO43− equivalent for 1 tonne (1000 kg) of biodiesel produced. Furthermore, the energy ratio (measured as output energy divided by input energy) for the entire production process was 1.97. These results demonstrated that biodiesel obtained from the valorisation of waste PAS provides a suitable alternative to fossil fuels.

Comparison of Ex-Situ and In-Situ Transesterification for the Production of Microbial Biodiesel

Microbial biodiesel is converted from microbial lipids via transesterification process. Most microbial biodiesel studies are focusing on the use of microalgal lipids as feedstock. Apart from using microalgae for lipid biosynthesis, lipids can also be extracted from other oleaginous microorganisms like fungi and yeast. However, there are gaps in the studies of lipid production from filamentous fungi, especially in-situ transesterification process. The aim of this project is to compare in-situ with the ex-situ transesterification of fungal biomass from Aspergillus oryzae. In ex-situ transesterification, two methods of lipid extraction, the Soxhlet extraction and the Bligh and Dyer extraction, were performed. For in-situ transesterification, two methods using different catalysts were investigated. Base-catalyzed in-situ transesterification of fungal biomass resulted on the highest Fatty Acid Methyl Esters (FAME) yield. The base-catalyzed in-situ transesterification was further optimized via Central Composite Design (CCD) of Response Surface Methodology (RSM). The parameters investigated were the catalyst loading, methanol to biomass ratio and reaction time. The optimization showed that the highest FAME yield was at 25.1% (w/w) with 10 minutes reaction time, 5% catalyst and 360:1 of the ratio of the methanol to biomass. Based on Analysis of Variance (ANOVA), the model was found to be significant according to the value of “Prob >F” of 0.0028. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Enhanced biodiesel production from wet microalgae biomass optimized via response surface methodology and artificial neural network

This study investigates modeling and optimal conditions for biodiesel production from exceedingly wet microalgae Chlorella pyrenoidosa using the catalyst, hydrochloric acid. Three levels of Box-Behnken design response surface methodology were used to optimize individual and interactive effects of parameter time (120–240 min), temperature (120–160 °C), solvent-to-wet biomass ratio (2.0–4.67), and hydrochloric acid concentration (2–4 M). Temperature was the most significant factor for direct transesterification of wet microalgae (low p-value (0.0001) and high F-value (53.89). The highest yield (19.90%) of fatty acid methyl ester was obtained on dry biomass weight basis under the optimum conditions of 240 min, 146 °C, 2.83 (vol/wt), and 3.86 M acid concentration. The artificial neural network and response surface methodology were trained with Box-Behnken design data to predict responses, and to develop and compare each model's predictive abilities. The accuracy of results indicates that both models predict the experimental data for fatty acid methyl ester yields with high correlation coefficients (R2) 0.94 and 0.92, respectively for artificial neural network and response surface methodology. The potential for producing biodiesel from C. pyrenoidosa is validated by the high yields of C18 fatty acid methyl esters. Experimental analysis demonstrated biodiesel quality in comparison with European and US standards.

Comprehensive Comparison of Hetero-Homogeneous Catalysts for Fatty Acid Methyl Ester Production from Non-Edible Jatropha curcas Oil

The synthesis of biodiesel from Jatropha curcas by transesterification is kinetically controlled. It depends on the molar ratio, reaction time, and temperature, as well as the catalyst nature and quantity. The aim of this study was to explore the transesterification of low-cost, inedible J. curcas seed oil utilizing both homogenous (potassium hydroxide; KOH) and heterogenous (calcium oxide; CaO) catalysis. In this effort, two steps were used. First, free fatty acids in J. curcas oil were reduced from 12.4 to less than 1 wt.% with sulfuric acid-catalyzed pretreatment. Transesterification subsequently converted the oil to biodiesel. The yield of fatty acid methyl esters was optimized by varying the reaction time, catalyst load, and methanol-to-oil molar ratio. A maximum yield of 96% was obtained from CaO nanoparticles at a reaction time of 5.5 h with 4 wt.% of the catalyst and an 18:1 methanol-to-oil molar ratio. The optimum conditions for KOH were a molar ratio of methanol to oil of 9:1, 5 wt.% of the catalyst, and a reaction time of 3.5 h, and this returned a yield of 92%. The fuel properties of the optimized biodiesel were within the limits specified in ASTM D6751, the American biodiesel standard. In addition, the 5% blends in petroleum diesel were within the ranges prescribed in ASTM D975, the American diesel fuel standard.

Metal-organic framework-derived Mg-Zn hybrid nanocatalyst for biodiesel production

Controlled synthesis of metal–organic framework (MOF)-derived Mg-Zn hybrid nanostructure was demonstrated for the development of basic catalysts applied in biodiesel production from soybean oil. Two types of Mg-Zn hybrid nanostructures were successfully fabricated under different atmospheres (Ar, air), (1) MgO nanoparticles encapsulated in Zn-based MOF (MgO@Zn-MOF) and (2) MgO nanoparticles uniformly decorated on ZnO nanoparticles derived from Zn-MOF (MgO@ZnO), respectively. Ultrafine MgO nanoparticles (<5 nm for MgO@Zn-MOF and ≈10 nm for MgO@ZnO) were successfully synthesized and homogeneously dispersed in the MOF-derived Mg-Zn hybrid nanostructures. Significant increases in the specific surface area (i.e., a maximum of 1048.5 m2/g) and corresponding basicity (i.e., by a maximum of 2.1 times) were achievable by using MOF-based strategy comparing to the Mg-Zn catalyst prepared by a conventional solution-based approach. High 3-cycle stability and high yields of fatty acid methyl esters at a stoichiometric feed ratio 3 were both achievable, 67.6% and 73.3%, by using MgO@Zn-MOF and MgO@ZnO as the catalysts, respectively. The work demonstrates a prototype study of utilizing MOF to develop high-performance basic nanocatalysts through fundamental understanding of material synthesis by design versus their corresponding activities.

Transesterification of Refined Sunflower Oil to Biodiesel Using a CaO/ZSM‐5 Powder Catalyst

AbstractThe production of biodiesel from refined sunflower vegetable oil over basic CaO/ZSM‐5 catalysts was investigated. Several catalysts with various loadings of CaO on ZSM‐5 were prepared, calcined at 800 °C, and characterized by N2 adsorption‐desorption, X‐ray diffraction, Fourier transform infrared spectroscopy, and CO2‐temperature‐programmed desorption techniques. Calcined catalysts were tested in the transesterification reaction and reaction conditions were optimized by varying the catalyst‐to‐oil ratio and reaction time. The most active catalyst was the CaO/ZSM‐5 catalyst with a 35 wt % loading which gave the highest fatty acid methyl ester yield. The high catalytic activity was attributed to the active basic sites generated following CaO addition. Furthermore, the catalyst demonstrated stability against the leaching process.

Designing an efficient and recoverable magnetic nanocatalyst based on Ca, Fe and pectin for biodiesel production

Magnetic catalysts containing Fe and Ca synthesized in the presence of pectin have demonstrated to be highly efficient in the transesterification reaction for biodiesel production. Catalysts were prepared by the co-precipitation method under a N2 atmosphere with Na2CO3 from a mixture of FeSO4, FeCl3, Ca(NO3)2, and pectin followed by calcination at 550 ˚C/6h. The influence of the Fe:Ca molar ratio in the catalytic activity on the transesterification reaction with methanol was evaluated in the presence or absence of pectin. The most efficient catalyst was prepared in the presence of pectin with a Fe:Ca molar ratio of 4.5:2 (FCP2), and the best experimental conditions were at 3 % wt catalyst, 14:1 of methanol: soybean oil molar ration and 7.5 h of reaction time, which resulted in a methyl ester yield of 96.3%. It was shown that the presence of the biopolymer in the synthesis enhances the catalytic activity of the material from 20% to 99% of biodiesel production. All materials were fully characterized by TEM, FTIR, TGA, BET, XRD and DC magnetometry. It was found that catalysts present high surface areas with a nanometer size (∼20 nm), giving rise to a superparamagnetic state with a magnetic saturation high enough for separation by means of a magnet. In contrast, catalysts prepared in the absence of pectin demonstrated poor performance in the transesterification reaction of biodiesel in the optimized experimental conditions. The magnetic properties and the biopolymer role are discussed.

Development of Microwave-Assisted Sulfonated Glucose Catalyst for Biodiesel Production from Palm Fatty Acid Distillate (PFAD)

Microwave-heating method for catalyst preparation has been utilized recently due to its shorter operation time compared to the conventional method. Glucose, a renewable carbon source can be partially carbonized and sulfonated via microwave heating which could result in highly potential heterogeneous carbon-based acid catalyst. In this study, the impacts of the carbonization and sulfonation parameters during the catalyst preparation were investigated. Catalysts prepared were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), X-Ray Diffraction (XRD), Brunauer-Emmet-Teller (BET), and Temperature Programmed Desorption–Ammonia (TPD-NH3). Analysis of the carbonization screening process discovered that the best incomplete carbonized glucose (ICG) prepared was at 20 minutes, 20 g of D(+)-glucose with medium microwave power level (400W) which exhibited the highest percentage yield (91.41%) of fatty acid methyl ester (FAME). The total surface area and acid site density obtained were 16.94 m2/g and 25.65 mmol/g, respectively. Regeneration test was further carried out and succeeded to achieve 6 cycles. The highest turnover frequency (TOF) of the sulfonated catalyst was methyl palmitate, 25.214´10−3 s−1 compared to other component of the methyl ester. Kinetic study was developed throughout the esterification process and activation energy from the forward and reverse reaction was 3.36 kJ/mol and 11.96 kJ/mol, respectively. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Statistical Optimisation using Taguchi Method for Transesterification of Reutealis Trisperma Oil to Biodiesel on CaO-ZnO Catalysts

Optimisation of biodiesel production from non-edible Reutealis Trisperma oil (RTO) was investigated using Taguchi method. Biodiesel was produced via consecutive esterification and transesterification reactions. Esterification of RTO was carried out using acid catalyst to decrease the amount of free fatty acid from 2.24% to 0.09%. Subsequent transesterification of the treated oil with methanol over a series of CaO-ZnO catalysts was optimized based on the L9 Taguchi orthogonal approach. The optimization parameters are Ca/Zn ratio (0.25, 0.5, and 1), methanol/oil ratio (10, 20, and 30) and reaction time (0.5, 1, and 2 h). CaO-ZnO catalysts at variation of Ca/Zn ratios were prepared using co-precipitation method and characterized using XRD, SEM, TEM, and FTIR analysis. The amount of methyl ester yield was used as the response parameter in the S/N ratio analysis and Analysis of Variance (ANOVA). The optimum parameter for RTO transesterification to biodiesel was determined at Ca/Zn ratio of 1, methanol oil ratio of 30 and reaction time for 2 h. Transesterification under these optimized parameter generated 98% of biodiesel yield, inferring the validity of the statistical approach. Furthermore, ANOVA analysis also confirmed that all the parameters were significantly contributed at approximately equal percentage towards the amount of biodiesel. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Chitosan-starch biopolymer modified kaolin supported Pd nanoparticles for the oxidative esterification of aryl aldehydes

A mild and efficient green protocol has been disclosed for selective oxidative esterification of various aldehydes over a novel Pd fabricated chitosan-starch polyplex encapsulated Kaolin (Kaolin@CS-starch-Pd) as a heterogeneous and reusable biocompatible nanocatalyst. Molecular oxygen was used as an oxidizing agent to generate water as the sole by-product. A wide variety of aldehydes was converted to their methyl esters in high yields. The process involved gentle reaction conditions to avoid any type of pre-activation. Structural features of the catalyst were determined through FT-IR, FE-SEM, TEM, EDX, elemental mapping, XRD and ICP-OES analyses. The material was found to be stable enough toward Pd leaching. Durability of Kaolin@CS-starch-Pd was further justified by retaining its catalytic activity through successful reusability for several times.

Development of CaO supported on modified geopolymer catalyst for transesterification of soybean oil to biodiesel

Heterogeneous base catalysts, CaO supported on modified geopolymer (Geo), were developed and characterized as low-cost catalyst for biodiesel production from the transesterification of soybean oil. Geo was modified and synthesized by facile method, meta-kaolin and fumed silica were employed as sources of silica, alumina and, foaming agent (Al metal). The modified Geo was then compared to the conventional Geo without foaming agent (unfoamed-Geo). The catalysts, CaO with various loadings supported on Geo, were prepared by applying microwave radiation and subsequent calcination in air at 600 °C. The addition of Al metal during the synthesis of a geopolymer resulted in larger pore size. The results from CO2-TPD and XPS suggested that the calcium species dispersed with strong interactions in the aluminosilicate network of the geopolymer structure leading to strong basicity of the catalysts. The reactivity results showed that the fatty acid methyl ester (FAME) yield of 30%CaO/Geo was 93.12 ± 0.48%, larger amount than that of 30%CaO/unfoamed-Geo (70.87 ± 0.22%). Moreover, 30%CaO/Geo could be reused for at least 3 runs, suggesting a promising catalyst for cost-effective biodiesel production.

Multi-response optimization of transesterification reaction for biodiesel production from castor oil assisted by hydrodynamic cavitation

With the increasing energy demand, fossil fuel depletion rate is increasing, therefore a need to develop sustainable and energy-efficient biodiesel production systems is arising which can compensate for the rate of fossil fuel depletion. The current study aims to analyze biodiesel production from castor oil using a novel hydrodynamic cavitation reactor. Response surface methodology (RSM) coupled with Box-Behnken design was incorporated to carry out the optimization of reaction parameters (reaction temperature, methanol to oil molar ratio, catalyst amount, and reaction time) to obtain desired castor oil methyl ester (COME) yield, functional exergy efficiency (FEE), Universal exergy efficiency (UEE) and normalized exergy destruction (NED). The developed model shows higher goodness of fit with values of R2 > 99% and R2adj > 98% for all these responses. Desirable reaction conditions for maximum COME yield (92.31 %) were: 57.9 °C temperature, 10.3:1 MeOH:Oil molar ratio, 1.05 %wt. catalyst amount and 58.94 min reaction time whereas based on exergetic indicators along with COME yield using multi-response optimization the same were: 60.3 °C temperature, 9.82:1 MeOH:Oil molar ratio, 1.06 %wt. catalyst amount and 50.86 min reaction time. The COME yield of 93.83 % and 92.27 ± 0.43%, FEE of 86.85% and 85.13 ± 0.40%, UEE of 98.21% and 98.22 ± 0.18%, NED of 0.14 and 0.13 ± 0.01 were predicted and experimentally calculated respectively at optimized reaction conditions considering composite desirability of all the responses. Consideration of exergetic indicators in multi-response optimization using RSM resulted in reduction of reaction time and exergy destruction by 14% and 15% respectively.

Improving biodiesel yield from pre-esterified inedible olive oil using microwave-assisted transesterification method

In the present research, biodiesel production from olive oils with different initial free fatty acid concentrations (2.5, 5.0, and 10.0%) was evaluated. A two-stage acid-catalyzed esterification and alkaline-catalyzed transesterification (ACT) process using the microwave heating method was compared with the traditional heating method. Free fatty acid was reduced to less than 2.0% in the first stage. Although no significant difference was observed between microwave and traditional esterification methods in terms of fatty acid reduction, the microwave treatment significantly decreased reaction time by 92.5%. Comparing microwave ACT results with those of the traditional heating method showed that the microwave can significantly increase methyl ester yield and purity, and simultaneously decrease reaction time. Physical constants of methyl esters were also improved using the microwave heating method. Therefore, the microwave heating method can be regarded as an efficient method instead of the two-stage method for biodiesel production. This method is capable of using inedible olive oil with high concentrations of free fatty acids.

Application of deep eutectic solvent in biodiesel reaction: RSM optimization, CI engine test, cost analysis and research dynamics

In this study, biodiesel was produced from waste cooking oil (WCO) in one step process with crude glycerol-ChCl based deep eutectic solvent (DES) and NaOH catalyst. Response surface methodology (RSM) technique was employed in predicting the optimal operating conditions and to study the relationship between reaction parameters and the yield of fatty acid methyl ester (FAME). The RSM coefficient of determination (R2) was observed to be 0.9965. The highest yield of biodiesel was 95% at the optimum reaction temperature of 65 °C with a reaction time of 90 min. The FAME produced was in compliance with the American standard for testing materials (ASTM) D6751-07 (2007) standards. CI engine test of B100 biodiesel fuel emitted lesser CO (2.01 g/kWh), HC (0.02 g/kWh) for engine load of 100% with little increase in CO2 when compared to petroleum-based diesel (PBD). Lower calorific value of biodiesel resulted in higher brake specific fuel consumption (BSFC) compared to the PBD. Computed biodiesel production cost was approximately 833.35 USD/ton. This investigation opens new pathway for utilizing crude glycerol-ChCl based DES as co-solvent for transesterification and other chemical reactions.

Methyl Esterification of Oleic Acid in Supercritical Methanol with Methyl Formate

Fatty acid methyl esters, which are used as biodiesel, can be produced by methyl esterification of fatty acids in supercritical methanol. However, in a reverse reaction, methyl esters are hydrolyzed to regenerate fatty acids due to the presence of water, which is produced by the esterification reaction, making it difficult to reduce the fatty acid content sufficiently. In this study, oleic acid was treated in supercritical methanol at 310 °C/20 MPa with a flow-type reactor by adding methyl formate to improve the yield of methyl ester. As a result, adding methyl formate improved the methyl ester yield approximately from 90 to 95 wt% compared with the treatment using methanol only. Methyl formate was hydrolyzed instead of fatty acid methyl esters, producing formic acid and methanol. Formic acid can be decomposed into gases such as H2 and CO2 by thermal decomposition in supercritical methanol. As these reactions consume water, removing it from the reaction system, the reaction equilibrium was considered to be shifted in the direction to improve the methyl ester yield.

Production and Characterization of Biodiesel from Avocado Peel Oils using Experimental Analysis (ANOVA)

The crisis of energy due to the increasing awareness of the depletion of fossil fuel resources, biodiesel is an alternative energy source and promising potential energy that grows rapidly, due to its high contribution to the environment friendly, renewable, non-toxicity, biodegradability, essentially sulfur-free, and as a strategical source of renewable energy in substitution to diesel oil and contributes a minimal amount of net greenhouse gases. In this study, the extracted oil used for biodiesel production from waste avocado peel was investigated in a laboratory approach. Experimental results evaluate the major optimum process parameters for base-catalyzed transesterification on biodiesel yield as well as its properties. The most important variables affecting methyl ester yield during the transesterification reaction are the molar ratio of alcohol to oil and the reaction temperature. A 95.2% FAME conversion was obtained using a methanol/oil ratio of 6:1, 1.21g NaOH, reaction time 67.5 min, and 60 0C reaction temperature. Important properties of (characterization) produced biodiesel are, (pHof 7.8, specific gravity of 0.88, density at 15 0C, kg/m3, the kinematic viscosity of biodiesel was found to be 4.22 m 2·s −1 at 40 0C, the flashpoint was 161 0C and Cetane number of 49 are well-matched the relevant international standards for biodiesel quality produced. This result shows that the oil obtained from avocado peel can be used for biodiesel production as an alternative fuel as compared to those of ASTM and EN standards.

Trends in Sonochemical and Hydrodynamic Reactor Strategies for Catalytic Production of Biodiesel: Effects of the Influencing Process Parameters and Kinetics

Biodiesel researchers need to understand the optimal conditions involved in the production of biodiesel from readily available biological sources, as several research works have reported on biodiesel production. Therefore, this paper emphasizes specifically, the process parameters involved in biodiesel production and how they affect biodiesel yields. These parameters include, but not limited to the feedstock selection, catalyst type to use, free fatty acid, temperature, kinetics, hydrodynamics and reactor conditions. In biodiesel synthesis, a high fatty acid methyl ester yield of up to 100%w/w at 60 oC has been reported, which occurred with a methanol to oil molar ratio of 3.75, and 60 min reaction time. Homogeneous catalysts seems promising for the production of biodiesel, although they possess disposal challenges and reusability issues. In addition, carbon-based catalysts from natural sources have been used to resolve the presence of free fatty acids in biodiesel synthesis that results in the formation of soap. These carbon-derived catalysts prove their efficiency when modified with acids. The reactor suitable for biodiesel reaction, assume several configurations, like the batch, fixed bed and semi-batch configurations, with their respective reaction conditions. Furthermore, in the design of a hydrodynamic cavitation reactor operating on the rotor-stator mechanism, research has shown that the ratio of rotor to stator diameter Dr/Ds is maintained at 0.73 for efficient operation. Hence, a proper understanding of the process chemistry and techniques involved in biodiesel synthesis would ensure a high desired yield and sustainable process route.

Valorization of de-oiled microalgal biomass as a carbon-based heterogeneous catalyst for a sustainable biodiesel production

In this study, a novel carbon-based solid acid catalyst was synthesized by carbonization of de-oiled microalgal biomass followed by sulfonation. The effect of catalyst synthesis conditions such as carbonization temperature, sulfonation time, and H2SO4 concentration on the surface acidity of the catalyst and free fatty acid conversion was determined. The de-oiled microalgal biomass-based solid acid (DMB) catalyst was predominantly composed of carboxylic, phenolic, and sulfonic groups as indicated by the FTIR analysis and supported by the XPS analysis. The catalyst was further characterized by various methods to determine its physiochemical properties. A maximum fatty acid methyl ester (FAME) yield of 94.23% for microalgal oil (AO) and 96.25% for waste cooking oil (WCO) was obtained under optimized transesterification conditions. The catalyst exhibited high catalytic activity (FAME yield >90%) until the fourth cycle. Most of the biodiesel properties were within the permissible limit of EN 14,212 and ASTM D6751 standards.

Optimisation of biodiesel production from Eisenia fetida earthworms oil using the transesterification method

ABSTRACT The current study was performed for the optimisation of the biodiesel production from E. fetida earthworms oil using the transesterification method. Rice husk was sulphonated by sulphuric acid and it was identified by the Fourier Transform Infrared Spectrometer (FTIR) technique and Scanning Electron Microscope (SEM) image. The effects of reaction temperature (50–70°C), alcohol-to-oil molar ratio (9:1–15:1), catalyst amount (3–5 wt%) and residence time (1–3 h) on fatty acid methyl esters (FAME) yield were assessed. Response Surface Methodology (RSM) was used to assess the actual and predicted FAME values. The results of the FTIR technique showed the presence of different surface functional groups (silanol, hydroxyl, etc.) on the silica-based catalyst. The results for SEM image showed fine spherical particles. A good agreement between actual and predicted values for FAME yield was observed. The optimal conditions of the parameters for FAME yield obtained from the software were as follows: reaction temperature = 68.53°C, methanol to oil molar ratio = 13.73:1, catalyst amount = 3.43 wt% and residence time = 3 h. Under optimal conditions, FAME yield reached to 93.2%. The theoretical FAME yield predicted under the above conditions was 94.68%.

Biodiesel production through transesterification of Chlorella vulgaris: Synthesis and characterization of CaO nanocatalyst

Current research deals with the effective, economic and ecofriendly conversion of algal oil into biodiesel using Calcium oxide (CaO) nanocatalyast. CaO nanoparticles were used as an alkaline catalyst for the transesterification of the indigenous green alga, Chlorella vulgaris oil into biodiesel. The catalyst was subjected to different calcination temperatures and their effect on complete transesterification of algal oil at different concentrations was also studied. The characteristics of the nanocatalyst were investigated using UV–Vis spectrophotometer, Fourier-Transform Infrared spectroscopy (FTIR), powder X-ray Diffractometer (XRD) and Field Emission Scanning Electron Microscopy (FESEM) equipped with Energy Dispersive Spectroscopy (EDS). It was found that various parameters such as reaction time, temperature and catalyst amount influences the fatty acid methyl esters (FAME) yield. The ideal conditions for transesterification process were optimized as a methanol to oil molar ratio of 9:0.6, a reaction period of 4 h, a catalyst loading at 4% and a reaction temperature of 80 °C. Gas chromatographic analysis revealed a fatty acid profile highly suitable for biodiesel production. A catalyst concentration of 3 mg.L-1 of CaO synthesized at 400 °C was found to be ideal for the transesterification process. These approaches could make massive impact on the large scale biodiesel production minimizing the hefty capital costs.