Oil Molar Ratio Research Articles

Production of biodiesel from waste cooking oil using a novel surface-functionalized CaMoO4/ TiO2 solid catalyst

This study involves the synthesis of a mesoporous CaMoO4/TiO2 solid catalyst through the impregnation method. The catalyst, known for its novelty, efficiency, and recyclability, was thoroughly characterized using various techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDAX), Thermogravimetric Analysis (TGA), Brunauer-Emmett-Teller (BET), and Barrett-Joyner-Halenda (BJH) studies. Waste cooking oil is analysed using FTIR spectroscopy for its free fatty acid content. In addition, the specific catalytic activities are investigated under a variety of reaction conditions. A yield of 95.6 % is achieved under the standard trans esterification reaction operating parameters such as catalyst loading of 4 wt %, methanol to waste cooking oil molar ratio of 15:1 (v/v), reaction duration of 70 min, reaction temperature of 55 °C, stirring speed of 270 rpm, and temperature of calcination as 650 °C. The reaction kinetics (pseudo first order) is also studied. Solid catalysts can also be reused up to five successive times. Biodiesel is characterized by FTIR and 1H NMR studies to examine the presence of functional and methyl ester groups respectively, and the extracted biofuel met the specifications of ASTM D 6751 norms for standard diesel fuel.

Green biodiesel production from Nannochloropsis microalgae-derived oil using ZnAl-LDH catalyst: Process optimization and kinetic study

The green production of biodiesel using Nannochloropsis microalgae, a renewable and environmentally friendly source, was successfully conducted by application of a calcined ZnAl layered double hydroxides structure (LDH) catalyst. The ZnAl-LDO catalyst was prepared through the urea synthesis method, followed by calcination at 400 °C. XRD was used to investigate the crystallite characteristics, N2-BET to analyze surface properties and pore size, and CO2-TPD to identify the active basic sites strength. Bligh and Dyer’s method was utilized for oil extraction with a yield of 38 %. Upon analyzing the fatty acid profile of derived oil, a synthetic oil containing oleic and palmitic acids was utilized in this process. The experiments were designed using the response surface methodology (RSM) method and the optimized parameters were obtained at 149.59 °C, 118.92 min, 3.91 wt% catalyst loading, and 11.68:1 methanol to oil molar ratio for the biodiesel yield of > 98 %. The pseudo-first-order esterification reaction kinetic was investigated and the activation energy was determined to be 28.53 kJ.mol−1. Furthermore, the process can be applied to microalgae solid biomass as well. In-situ transesterification of microalgae with a yield of FAME over 90 % also has been carried out.

Optimization of Enzymatic Transesterification of Acid Oil for Biodiesel Production Using a Low-Cost Lipase: The Effect of Transesterification Conditions and the Synergy of Lipases with Different Regioselectivity.

This study describes the enzymatic production of second-generation biodiesel using low-quality acid oil as a substrate. Biolipasa-R, a commercially available and low-cost lipase, was employed for enzymatic transesterification. Response surface methodology was applied to optimize the enzymatic transesterification process. The optimal conditions for biodiesel production, which comprised 42% lipase concentration (per weight of oil), 32% water content (per weight of oil), a methanol to oil molar ratio of 3:1, pH 7.0 and reaction temperature 30°C, resulted in the highest fatty acid methyl ester (FAME) content (71.3%). Subsequently, the synergistic effect of two lipases with different regioselectivities under the optimum transesterification conditions was studied, aiming at the enhancement of process efficiency. The transesterification efficiency of immobilized Biolipasa-R was determined and compared to that of Biolipasa-R in its free form. The results revealed a good performance on FAME content (66.5%), while the recycling of immobilized lipase resulted in a decrease in transesterification efficiency after three consecutive uses.

Use of Sulfuric Acid-Impregnated Biochar Catalyst in Making of Biodiesel From Waste Cooking Oil Via Leaching Method

The biodiesel synthesis of waste cooking oil (WCO) over a impregnated biochar catalyst was systematically studied. This research aimed to prepare Biochar-based material that comes from coconut coir, activate it, and apply it as a catalyst to the esterification reaction of high-FFA waste cooking oil. Activation of the catalyst was done by impregnation H2SO4 solution in Biochar. The obtained catalyst was characterized by FTIR, XRF, XRD, surface area analyzer, and SEM-EDS. The esterification process was conducted by varying the catalyst weight (5, 7, and 10 wt%) and the reaction temperature (55 and 60 °C). The obtained liquid yields were characterized by GC-MS. The study found that the esterification process worked best with 10 wt% catalysts, a 1:76 mole ratio of oil to alcohol, and a reaction temperature of 60 °C. The waste cooking oil was successfully converted into biodiesel, reaching 84.50% of yield and 77.30% of purity (methyl ester content). Meanwhile, testing using national biodiesel standards with parameter limits of density, viscosity, iodine number, and acid number shows results that meet the requirements. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

A Novel PETG Microchannel Reactor for Microwave-Powered Biodiesel Production

Biodiesel stands at the forefront as a replacement for fossil diesel in compression ignition engines, particularly in the transportation sector where diesel engines are the primary movers. However, biodiesel production is hampered by poor heat and mass transfer during the transesterification reaction, leading to long production times and high costs due to inefficient energy utilisation. This study targets heat and mass transfer issues during the production of biodiesel via a synergic approach that combines microwave-assisted heating and microfluidics via a polyethylene terephthalate glycol (PETG) microchannel reactor. The transesterification reaction of palm oil and methanol was investigated using a full factorial design of experiments (DOE) method. Biodiesel yield was quantified via gas chromatographic analysis, and the results were optimised using statistical analysis. Optical analysis of slug quantification within the microchannel revealed that small slugs, smaller than 1 mm, accelerated the transesterification reaction. The composite-optimised experimental results, aimed at minimising energy costs and environmental impacts while maximising fatty acid methyl ester (FAME) yield, indicate a reaction temperature of 50 °C, a catalyst loading of 1.0 wt.%, and a 3:1 methanol to oil molar ratio. Regression analysis revealed that the reaction temperature was statistically insignificant when utilising the PETG microchannel reactor. This key finding positively impacts biodiesel production as it relates to significantly reduced energy intensity, costs, and emissions. Overall, this research work paves a pathway toward an energy-efficient and sub-minute rapid transesterification reaction, highlighting the effectiveness of microwave heat delivery and effects of microfluidics via the PETG microchannel reactor in overcoming heat and mass transfer barriers in biodiesel production.

Exploitation of Annona reticulata leaf extract for the synthesis of CeO2 nanoparticles as catalyst for the production of biodiesel using seed oil thereof

Annona reticulata plant components such as leaves and seeds are successfully employed as low-cost and environmentally-safe sustainable materials for the synthesis of cerium oxide nanoparticles and biodiesel production. The synthesized CeO2 NPs worked well as a catalyst to convert A. reticulata oil into biodiesel. At a methanol to oil molar ratio of 8.97:1, a catalyst (CeO2 NPs) loading of 2.97 wt %, and reaction time of 56.4 min, the maximum 96.8 % biodiesel yield was attained. A pseudo-first-order reaction with activation energy (Ea) of 49.77 kJ/mol and a frequency factor (A) of 1.8 x 105 min−1 is consistent with the Annona reticulata methyl ester (ARME) production. The performance and emission characteristics of diesel engines were found to be significantly impacted by the use of CeO2 NPs. While the BSFC of ARME20CeO250 and ARME20CeO2100 decreased by 2.04 % and 5.10 %, respectively, the BTE of ARME20CeO250 and ARME20CeO2100 increased by 1.8 % and 2.41 %, in contrast to ARME20 at maximum load. When CeO2 nano-additive (100 ppm) is added to the ARME20 blend, the CO, HC, and NOx are reduced by 42 %, 35.59 %, and 5.94 %, respectively, in comparison to the ARME20 fuel. Thus, the A. reticulata plant may be seen as an eco-friendly source from its leaves extract, and the oil extracted from its seeds may be used as a feedstock for the effective production of biodiesel.

Ultrasonic-Assisted Preparation of Biodiesel Products from Vegetable Oils.

Utilizing vegetable oil as a sustainable feedstock, this study presents an innovative approach to ultrasonic-assisted transesterification for biodiesel synthesis. This alkaline-catalyzed procedure harnesses ultrasound as a potent energy input, facilitating the rapid conversion of extra virgin olive oil into biodiesel. In this demonstration, the reaction is run in an ultrasonic bath under ambient conditions for 15 min, requiring a 1:6 molar ratio of extra virgin olive oil to methanol and a minimum amount of KOH as the catalyst. The physiochemical properties of biodiesel are also reported. Emphasizing the remarkable advantages of ultrasonic-assisted transesterification, this method demonstrates notable reductions in reaction and separation times, achieving near-perfect purity (~100%), high yields, and negligible waste generation. Importantly, these benefits are achieved within a framework that prioritizes safety and environmental sustainability. These compelling findings underscore the effectiveness of this approach in converting vegetable oil into biodiesel, positioning it as a viable option for both research and practical applications.

Optimization of biofuel production from biomass using montmorillonite catalyst by development of predictive models

Fossil fuel depletion and their environmental problems lead to new research for production of alternative fuels. Biofuels are promising nontoxic and biodegradable energies obtained from renewable sources. Experimental studies of biofuel production and optimizing the properties are very time-consuming, cost-intensive, and difficult. Thus, recently there have been major interests in application of Machine Learning (ML) techniques to develop models for predicting biofuel production process and optimization. This study proposed novel ML approach based on Support Vector Machines (SVM), Multi-Layer Perceptron (MLP), and Adaboost on SVM base (Adaboost + SVM) algorithms optimized the production of biofuel from waste cooking oil through transesterification process and under montmorillonite (MMT) catalyst. The input variables for the models were chosen to be the temperature of the reaction (ranging from 100 to 200 °C), treatment time (ranging from 3 to 9 h), catalyst loading (ranging from 2 to 6 wt%), and methanol to oil molar ratio (ranging from 8 to 16). Meanwhile, the output of the models was selected to be the yield of biofuel production. The obtained results of three models were evaluated and compared and it was confirmed that the Adaboost + SVM model with highest regression coefficient (R2) of 0.971, was more accurate and could predict the biofuel production more properly. Additionally, the SVM model exhibited the highest maximum error with an MAE of 6.504 and an RMSE of 7.462. On the other hand, the Adaboost + SVM model showed the lowest error, with an MAE of 3.151 and an RMSE of 4.484. The MLP model had an MAE of 4.423 and an RMSE of 6.008, which falls between the other two models in terms of error. The optimization results obtained by the Adaboost + SVM model demonstrated that the optimal conditions giving the highest biofuel production of 96.79 % were found to be: reaction time of 8.62 h, catalyst loading of 4.88 wt%, methanol/oil molar ratio of 11.2, and reaction temperature of 152 °C.

Synthesis of HNTs-Ca/Zn catalyst for biodiesel production from acidulated palm oil: Optimized by GA-BP

The development of heterogeneous base catalyst with acid resistance has become a major topic in the current research on the biodiesel production process. Halloysite nanotubes (HNTs) is supported with bimetallic of calcium and zinc for modification and labeled as HNTs-Ca/Zn to show both the acid and base characteristics. Further, this supported catalyst is used to produce biodiesel from the acidulated palm oil through catalyzing transesterification in one-step in this study. The HNTs-Ca/Zn catalyst, synthesized by the impregnation method, is characterized by TG-DTG, XRD, XPS, TEM, SEM-EDX, nitrogen adsorption-desorption, CO2/NH3-TPD, FTIR and Raman. The capability of the HNTs-Ca/Zn catalyst in catalyzing transesterification is investigated, where the maximum yield of 95.22% is achieved with the molar ratio of Zn to Ca of 1.5. The advantage of HNTs-Ca/Zn1.5 catalyst is prominent when the transesterification source oil is acidulated, where the biodiesel yield of 92.66% is obtained even at the acid value of 26.02 mg KOH g−1. Besides, reusability of the catalyst is acceptable, where the yield of 77.91% is maintained after the fourth reused cycle. Further, the Genetic Algorithm-Back Propagation (GA-BP) neural network is used to train and predict the transesterification parameters of the reaction temperature, catalyst amount and methanol to oil molar ratio. The prediction of the biodiesel yield is reasonable. At the predicted reaction parameters of 158 °C, catalyst amount of 7.1 wt.% and methanol to oil molar ratio of 15.5, the predicted biodiesel yield is 98.71%, where the experimental verification value is 98.60%. Therefore, the HNTs-Ca/Zn catalyst is considered to demonstrate exceptional catalytic performance and recyclability, offering the potential for biodiesel production.

Effective transesterification of castor oil to biodiesel catalyzed by novel carbon-based calcium composite

A novel carbon-based calcium catalyst was prepared through impregnation-calcination method, and was successfully applied as an effective catalyst for transesterification of castor oil to produce biodiesel. The catalyst prepared through the calcination at 500 °C for 3 h (Ca/C-500–3) exhibited the optimal performance. The prepared carbon-based calcium catalyst had excellent crystallinity and morphology, high basicity and surface area according to the characterization analysis results. Based on the XPS analysis, the combination of CaO and C in Ca/C-500–3 could improve the oxygen ion donating ability, which was beneficial for the reaction of triglycerides with methanol. The optimum composite of carbon-based calcium catalyst (Ca/C-500–3) displayed the excellent catalytic activity in castor oil transesterification, and 95.44 % of biodiesel conversion was obtained with the following conditions: methanol to oil molar ratio of 18:1, catalyst dosage of 5 wt%, reaction temperature of 65 °C and reaction time of 3 h. The TOF indicated that Ca/C-500–3 was an efficiency catalyst. Meanwhile, the calculation results of E-factor and PMI manifested that the transesterification of castor oil to biodiesel catalyzed by Ca/C-500–3 was a green reaction. Ca/C-500–3 could retain its high catalytic activity after five reaction cycles. The LCC cost analysis results suggested that, using Ca/C-500–3 as catalyst, biodiesel production from castor oil as feedstock had lower production cost compared to other biodiesel productions. The various factors affecting the cost of producing biodiesel were investigated using sensitivity analysis. Finally, the possible mechanism of catalytic transesterification reaction using carbon-based calcium composites was revealed.

Preparing vegetable oils-based metalworking fluids by a hydrolysis-esterification two-step process

Oil-soluble esters of free fatty acids were synthesized with a 2-step process including the first step of reacting vegetable oil with water in the presence of sulfuric acid and p-Toluenesulfonic acid as a catalyst, followed by removing water and glycerol, and the second step of reacting the obtained free fatty acids with various polyhydric and fatty alcohols. The best conditions were 190 °C, 6 h, 30 to 1 water to oil molar ratio, 5 wt% PTSA catalyst loading in the hydrolysis reaction (the 1st step), and 150 °C, 10 h, 4 to 1 fatty acid to trimethylolpropane molar ratio, 1 wt% PTSA catalyst loading in the esterification reaction (the 2nd step). Under the best conditions, the process achieved the final product with the 87% yield of free fatty acid trimethylolpropane ester and 82% conversion of free fatty acid. Different esters were made concurring to the aforementioned conditions with distinctive polyhydric and fatty alcohols. Hydrolysis reactions facilitated by catalysts offer an alternative approach to traditional hydrolysis in supercritical conditions, enabling efficient substrate conversion under milder operating conditions. Furthermore, the inclusion of the obtained esters mixed with base oil and additives produced bio-based metalworking fluids with exceptionally lubricant performance in wear resistance, with a wear scar diameter of 0.33 mm.

Synthesis of biodiesel from the composite oil and process parameters optimization using artificial neural network

This study aims to investigate the effect of catalyst utilization (wt%), methanol to composite oil molar ratio (mole) and reaction thermal state (°C) on the biodiesel yield percentage of transesterification of novel composite oil (equal volume % of Castor oil, Mahua oil and dairy waste scum oil). Artificial neural network (ANN) based on central composite design was implemented to investigate the influence of catalyst utilization (1–3 wt%), methanol to composite oil molar ratio (6–12 molar) and reaction thermal state (55–65 °C) as the independent variables. Levenberg-Marquardt algorithm was used to predict the responses, biodiesel yield %. The fairness of the ANN prediction of biodiesel yield % is tested by means of coefficients of determination of training phase, validation set, test set and combined training, validation and test. The results revealed that the optimum catalyst utilization, methanol to composite oil molar ratio and reaction thermal state were determined as 3 wt%, 9 molar, and 65 °C for the maximum biodiesel yield of 94 ± 1% from the composite oil. The ASTM D6751 standard is employed to assess the quality of biodiesel derived from a blend of oils. The findings of this study indicate that the newly developed mixed oil is a viable feedstock for the production of biodiesel.

Valorization of slaughterhouse wastes through transesterification for sustainable biodiesel production using potassium hydroxide as a heterogeneous catalyst

In this research, biodiesel was synthesized from chicken gizzard using potassium hydroxide catalyst and the effects of operating parameters including catalyst weight percentage (0.005–0.015%), methanol to oil molar ratio (3:1 to 9:1), temperature (50–70 °C), contact time (4–6 h), and stirring rate (400–600 rpm) on the methyl ester conversion yield were investigated. This study is innovative as it explores the transesterification of chicken gizzard, a low-cost feedstock, which has not yet been investigated. Furthermore, the applied catalyst was characterized through BET, FTIR, FSEM, XRD, XRF, EDS/Map techniques, while GC analysis showed that heptanoeic acid (41.57%), arachidic acid (27.63%), and linoleic acid (15.48%) constituted the main constituents of the extracted oil. Based on BET analysis the specific surface area of the used catalyst was 358 m2 g−1 which is an appropriate value for the current purpose. The results revealed that the maximum biodiesel conversion yield (94%) was obtained under the optimal conditions of catalyst weight percentage at %0.01, methanol to oil ratio at a ratio of 6:1, temperature at 60 °C, reaction duration of 5 h, and stirring rate at 500 rpm. The regeneration studies demonstrated that the used catalyst can be used for 2 consecutive cycles with acceptable conversion yields. However, beyond this point, the yield deteriorates, dropping to below 90%. Furthermore, the comparison of the physical characteristics of the generated biodiesel, including density, viscosity, flame point, cloud point, pour point, aniline point, cetane number, and copper strip corrosion with ASTM-D675110 and EN-14214 standards showed that they were within the standards ranges which indicates that the produced biodiesel was a viable alternative to traditional diesel fuel. Considering the promising results obtained from biodiesel production utilizing chicken gizzard for the first time, this waste material can be deemed a cost-effective raw material for biodiesel production.

Kapok Derived Activated Carbon Catalyst Assisted in Biodiesel Production from Waste Cooking Oil

The present study aims to synthesize green carbon-based catalyst from kapok (Ceiba pentandra) using two different activating agents: KOH (CB1) and K2CO3 (CB2) with 1:1.0 (raw material: activating agent), at activation temperature of 400 °C and impregnation time of only 15 min. The synthesized catalysts were evaluated in the transesterification of waste cooking oil (WCO) into biodiesel. CB1 registered higher iodine number and percentage yield (1446.30 mg/g, 62.60 %) compared to 1200.23 mg/g and 53.50 % obtained for CB2. Several physico-chemical characterizations were subjected for kapok and the carbon catalysts such as Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM) and CHNS/O Analyzer. FTIR investigation showed the disappearance or reduction in peak intensity of several peaks at 1512-1200 cm-1 in the carbon catalyst compared to raw kapok, arising due to carbonization and activation processes. CHNSO analysis verified that both CB1 and CB2 registered high carbon content of 63.93 % and 62.86 %, respectively compared to the raw kapok (43.54 %). Morphological studies by SEM analysis showed appearance of cylindrical tube for all the samples. The biodiesel synthesis from WCO at 0.2 wt.% catalyst loading, methanol to oil (molar ratio of 3:1), reaction temperature of 60 ˚C for 1 h resulted in high catalysis over CB1 (89.57 %), followed by CB2 (87.46 %) and without catalyst (35.46 %). Large iodine number and high carbon content exhibited by CB1 was the probable reasoning for the accelerated activity of CB1 in the transesterification of WCO. To conclude, the present work showed a successful conversion of waste biomass into promising carbon catalyst for green synthesis of biodiesel from WCO.

Impact of additives from moringa stenopetela leaf extract and ethanol on the emission characteristics and performance of soybean biodiesel for single cylinder CI engine

The study investigates the effect of ethanol and Moringa antioxidant on the performance and emission characteristics of a Soybean biodiesel blend (B15, B20, and B25) using a direct injection, four-stroke, naturally aspirated, water-cooled single-cylinder diesel engine equipped with SCADA software. The effect of reaction parameters on FAEE yield such as, time, catalyst concentration, molar ratio of alcohol to oil, and blending quality, was optimized using the one factor at a time experimental technique. The maximum yield of 97.8% biodiesel was produced at the ideal catalyst concentration, blending quality, alcohol to oil molar ratio, and time of 1 h, are 1%, 12:1, and 500 rpm, respectively. The Rancimat method was used to assess the oxidative stability of pure biodiesel after the natural antioxidant (extracted from Moringa leaf) was added at concentrations of 1500, 2500, 3500, and 4500 ppm. The addition of antioxidants to biodiesel significantly increased its induction time from 4.52 to 19.98 h. Brake-thermal efficiency increased by 4.4% whereas brake-specific fuel consumptions decreased by 4.6% for B15E2M (15% SB+2E + M) when compared to B15. Emission characteristics of B25E2M showed higher reduction of CO, HC and NOx by 20.27%, 8% and 7% as compared to the B25 respectively. The physicochemical qualities, performance, and emission characteristics of B15 blends with additive are generally comparable to those of diesel fuel. In conclusion, both additives significantly improved the combustion performance of soybean biodiesel blend.

Utilization of Dairy Waste Scum Oil for Microwave-Assisted Biodiesel Production over KOH-Waste Eggshell based Calcium Oxide Catalyst

The sustainability can be maintained by utilizing the available waste as feedstock and catalysts such as dairy and eggshell waste respectively for biodiesel production. In this study, the calcium oxide (CaO) synthesized from calcined eggshell was doped with potassium hydroxide (KOH-ECaO) via wet impregnation method and analyzed the catalyst performance on biodiesel production from dairy waste scum oil (DWSO) via microwave-assisted transesterification. The catalyst was characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy equipped with Energy Dispersive X-ray (SEM-EDX), Brunauer-Emmett-Teller (BET) and Thermogravimetric analysis (TGA). The fatty acid methyl ester (FAME) contents were deduced by Gas Chromatography-Mass Spectrometry (GC-MS). The KOH-ECaO catalyst shows good potential based on the characterization analysis such as high pore size (25.5 nm) which is supported by SEM pattern analysis. The highest biodiesel production (75%) was obtained at optimum reaction parameters conditions. The optimized conditions were discovered to be 3 wt.% of catalyst, 16:1 of methanol to oil molar ratio, reaction temperature of 65°C and 15 minutes of reaction time as microwave provided faster reaction for the transesterification. These innovative results showed that KOH-ECaO could enhance the biodiesel production from DWSO which encourage the usage of waste for wealth product.

Production of Biodiesel from Candlenut Seed Oil (Aleurites Moluccana Wild) Using a NaOH/CaO/Ca Catalyst with Microwave Heating

Oil fuels derived from fossils are non-renewable, so over time, they will run out and have a negative impact on air pollution. To overcome this, there is a need for environmentally friendly alternative fuels from renewable sources such as biodiesel. This research used microwave heating with a CaO catalyst. NaOH-impregnated snail shells and active carbon support. This research aims to determine the effect of power on the conversion of candlenut seed oil into biodiesel using the NaOH/CaO/CA catalyst both in terms of compliance with the SNI 7182-2015 standard and analysis using GC-MS (Gas Chromatography-Mass Spectrometry). The synthesis of the NaOH/CaO/CA catalyst was carried out through wet impregnation and calcination at a temperature of 500°C and analyzed using gas sorption analysis (GSA). Then proceed to the transesterification process, where the power for microwave heating was varied to 300, 450, and 600 watts with a mole ratio of esterified oil and methanol, namely 1:10 for 3 minutes. The analysis results of the NaOH/CaO/CA catalyst using the GSA instrument have a surface area of 9.306 m2/g, pore volume of 0.033 cc/g, and pore diameter of 14.043 nm. Meanwhile, the results of the biodiesel analysis showed that the optimum biodiesel yield was 85.625% at 600 watts of power and had a kinematic density and viscosity that met the SNI 7182-2015 biodiesel standards. Analysis of biodiesel characteristics using GC-MS showed that the three most optimum biodiesel components were hexadecanoic acid, methyl ester (22.664%), 9,12-Octadedecadienoic acid (Z,Z)-, methyl ester (30.176%) and 9-Octadecenoic acid (Z)-, methyl ester (38.656%).

Optimization of biodiesel production in a high throughput branched microreactor

Biodiesel as a renewable and environmentally friendly fuel can be considered an alternative to fossil fuel in industries, and one of the promising approaches to developing biodiesel yield is its production in microreactors. However, the produced quantity from microreactors is limited which necessitates higher throughput microreactors to be produced, maintaining the high yield of biodiesel. Therefore, this study investigated the transesterification of waste cooking oil (WCO) with methanol in the presence of sodium hydroxide as the catalyst using a novel branched microreactor, used for higher throughput applications. Thus, a novel four-micro serpentine-based microreactor was designed and fabricated with no external tubing. Biodiesel is produced in the fabricated microreactor and the Box-Behnken Design method (BBD) in Minitab software was used to design the experiments with different operating conditions: methanol to oil molar ratio (6:1–12:1), catalyst concentration (0.5–1.5 wt%), and reaction temperature (55–65 °C) to optimize the biodiesel volume yield in the designed microreactor. The optimum biodiesel yield using GC–MS analysis was found to be 82.8 % at a methanol to oil molar ratio of 12:1, 1.5 wt% catalyst concentration, and reaction temperature of 59.4 °C while maintaining the reactants’ inlet flow rate of 20 µL/s. Production of up to 35 mL biodiesel was collected in 30 min only. In addition, the microreactor achieved up to 97 % conversion at inlet flow rates of 8.5 µL/s.

Optimization and kinetic studies for biodiesel production from dairy waste scum oil via microwave assisted transesterification

This study presents an investigation of the optimization and kinetic aspects of the microwave (MW) heating transesterification process for converting dairy waste scum oil (DWSO) into biodiesel using lithium impregnated calcium oxide from eggshell (Li-ECaO) as a catalyst. The transesterification was done via microwave heating while varying catalyst loading (1 – 5 wt%), methanol to oil molar ratio (6 – 18:1), temperature (55 – 75⁰C), and reaction time in the range of 5 – 25 min. Response Surface Methodology (RSM) optimized the process parameters, yielding an impressive 90.5% biodiesel yield. The optimal operating conditions were determined 3 wt% catalyst loading, 18:1 methanol to oil molar ratio, a reaction temperature of 65ºC, and a reaction time of 25 minutes. A thorough kinetic analysis of the transesterification reaction for the MW heating transesterification of DWSO by Li-ECaO was performed at various temperatures (45 – 75ºC). The pseudo-first order kinetic study of the reaction revealed a moderately low activation energy of 38.86 kJ/mol and a high pre-exponential factor of 1141.27 s−1, which is consistent with previous studies. Importantly, the observed activation energy was lower than that of conventional methods, highlighting the potential of MW heating as a viable technique for future biodiesel production, and using wastes such as DWSO and eggshell could contribute to being greener and environmentally friendly.

Agro-industrial residue of Pouteria sapota peels as a green heterogeneous catalyst to produce biodiesel from soybean and sunflower oils

We report the use of ash from the agro-industrial waste of Pouteria sapota peels as a reusable heterogeneous catalyst to produce biodiesel from soybean and sunflower oils. The heterogeneous catalyst was prepared by activating raw Pouteria sapota peel powder at 500 °C for 2 h. The physicochemical and structural properties of the ash were evaluated by SEM-EDS, XRD, FTIR, BET analyses, and its basicity was determined through acid-base titration. The good activity of the ash-based catalyst was attributed mainly to the presence of potassium chloride (KCl), a specific surface area of 1.432 m2 g−1, and its high basicity of 9.069 mmol g−1. A maximum conversion yield of 92% was achieved for both the oils under optimized reaction conditions. For the soybean and sunflower oils, the optimum parameters were 3 wt% and 5 wt% of catalyst charge, methanol to oil molar ratio of 6:1 and 9:1, and a reaction time of 240 min, respectively. The reactions were performed at 65 °C under stirring at 400 rpm. The physicochemical properties of soybean and sunflower biodiesel satisfactorily complied with the International Standard of the American Society for Testing and Materials (ASTM-D6751) and the European Standardization (EN-14214).