Oil Molar Ratio Research Articles

Pilot scale production of biodiesel from Madhuca indica and comparative techno-economic analysis.

The increasing global energy demand and the depletion of conventional fossil fuel supplies, coupled with greenhouse gas emissions from excessive fossil fuel use, open the door for consideration of renewable energy sources. Among these, biodiesel has arisen as a sustainable and feasible alternative, providing environmental and economic advantages by reducing dependence on finite fossil fuel resources. This study focuses on biodiesel production from Madhuca indica seed oil using three catalysts: HCl, KOH, and dolomite. The optimum reaction parameters were methanol:oil molar ratio 20:1, catalyst weight percentage 5% and reaction temperature 60°C. The reaction duration for each catalyst was 20h for acid-catalyzed (HCl) process, 2h for alkali-catalyzed (KOH) process, and 10h for dolomite-based reaction. The biodiesel yields for acid, alkali, and dolomite catalysts are 94%, 96%, and 93%, respectively. According to the techno-economic study conducted with Aspen Plus, the payback periods for transesterification based on acid, alkali, and dolomite would be 3.66, 5.42, and 2.96years, respectively. These results demonstrate the economic viability of dolomite as a green catalyst with competitive biodiesel yields and the shortest payback period.

Ethanol-Based Transesterification of Rapeseed Oil with CaO Catalyst: Process Optimization and Validation Using Microalgal Lipids

Microalgal oil has been increasingly studied as a feedstock for biodiesel production through transesterification reactions using heterogeneous catalysts. This route offers several benefits, including catalyst reuse, ease of separation, and improved safety, while addressing environmental and technical issues associated with using homogeneous acids and bases. Most studies use methanol for the transesterification, and few studies have investigated the transesterification of microalgal oil using ethanol. Beyond the environmental benefits of microalgae compared to plant-based biomass, replacing methanol with bioethanol is advantageous due to its lower cost and reduced toxicity. If the emulsion issue between the produced biodiesel and ethanol is resolved, ethanol could be a more environmentally friendly alternative for green fuel production. This study evaluated various metal oxides as catalysts for the transesterification of rapeseed oil using ethanol as both reagent and solvent to improve miscibility. From catalyst screening, CaO showed the highest fatty acid ethyl esters yield and this catalyst was then tested at different reaction times in two systems (round-bottom flask and autoclave reactor) for the transesterification of both rapeseed and microalgal (Scenedesmus sp.) oil. The highest reaction yield was 86.0% for rapeseed oil and 81.3% for microalgal oil using 114:1 ethanol: oil molar ratio with CaO in an autoclave reactor. This work addresses the limited studies on ethanol in microalgal oil transesterification, demonstrating the effectiveness of CaO as a catalyst. It highlights the potential of ethanol as a greener, cost-effective alternative to methanol for biodiesel production.Graphical

Catalytic epoxidation of waste palm kernel oil using in situ performic acid formation

AbstractThe use of renewable resources in the epoxidation process can reduce the dependence on non‐renewable petroleum resources and contribute to a more environmentally friendly chemical industry. This study aims to investigate the epoxidation of waste palm kernel oil as a renewable feedstock. The synthesis of epoxidized waste palm kernel oil was conducted by reacting waste palm kernel oil, formic acid, and hydrogen peroxide in a one‐pot system. Currently, there is no reported literature on the simultaneous application of a catalyst for the epoxidation of waste palm kernel oil derived from industrial waste. The optimum process parameters were determined, including hydrogen peroxide to waste palm kernel oil molar ratio (1.5:1), formic acid to waste palm kernel oil molar ratio (0.5:1), and stirring speed (300 rpm). The optimum relative conversion to oxirane of epoxidized waste palm kernel oil was 88%. A mathematical model was developed using numerical integration based on the fourth‐order Runge–Kutta method as follows: = 0.894 mol·L−1·min−1, = 7.420 mol·L−1·min−1, and = 0.086 mol·L−1·min−1. Based on the findings of the kinetic study, the kinetic model was validated due to its minimal simulation error.

Hybrid in-situ and ex-situ hydrolysis of catalytic epoxidation neem oil via a peracid mechanism

The depletion of oil reserves and their price and availability volatility raise researchers’ concerns about renewable resources for epoxidized material. This study aims to produce in situ and ex-situ hydrolyzed dihydroxy stearic acid via the epoxidation of neem oil. Epoxidized neem oil was synthesized using in situ-generated performic acid. The Taguchi method was employed to optimize hydrolysis, aiming for maximum production of dihydroxystearic acid. The Taguchi method’s signal-to-noise (S/N) ratio analysis identified optimal conditions for producing dihydroxy stearic acid with a maximum hydroxyl value of 129.4 mg KOH/g: (1) water/neem oil molar ratio of 2:1, (2) water addition time of 90 min, and (3) reaction stop time of 120 min. ANOVA revealed the significant order of parameters as reaction stop time > water addition time > water/neem oil molar ratio. Lastly, a mathematical model was developed using MATLAB, applying the fourth-order Runge–Kutta method and simulated annealing optimization to determine the best-fitting kinetic model. This research aids in transforming neem oil into a value-added product, reduces petroleum dependence, and provides key insights into reaction kinetics for industrial applications.

The Synthesis of Methyl Ester Nitrate from Ketapang Seed Oil (Terminalia catappa L.)

The synthesis of methyl ester nitrate (MEN) from ketapang oil (Terminalia catappa L.) have been carried out. This study aims to determine the yield and the characteristics of MEN. In this study, ketapang seed oil was obtained from the soxhlet extraction process followed by an evaporation process to separate the oil from the solvent. MEN can be produced from ketapang seed oil by esterification to convert all of FFA became ester, followed by transesterification that intended to produce ester from triglycerides and nitrationthat is reaction of esther and HNO3 to create MEN. Evaporated oil is esterified using methanol with a mole ratio of oil: methanol (1: 6), then the transesterification process using methanol with a mole ratio (1:15) gives a yield of 86%. The transesterification product was then nitrated using HNO3 and H2SO4 for 4 hours with a yield of 83%. Characterization of methyl ester using GC-MS characterization showed the presence of methyl palmitoleate (C17H32O2), methyl palmitate (C19H34O2), methyl oleate (C19H36O2), methyl 13-octadecanoic (C19H36O2), methyl stearate (C19H38O2), and methyl 18-nonadecanoic (C21H42O2). Characterization MEN using a FTIR spectrophotometer showed the presence of a C-ONO2 group at wave number 1550 cm-1, NO2 group at wave number 1365 cm-1 and a C-N group at wave number 1118 cm-1. It shows that MEN can be synthesized from ketapang seed oil.

Preparation and Characterization of Sulfonated CaO Catalyst for Biodiesel Production from Waste Cooking Oil

Biodiesel production depends on raw materials. Low-quality oils, such as cooking oil, crude palm oil, and sludge oil, are used to reduce costs, and they contain free fatty acids (FFA) and water. Soap can be produced when using the alkaline catalyst during transesterification. In this work, the sulfonation method prepared the esterification of waste cooking oil by sulfonated CaO as a bifunctional catalyst. The sulfonated CaO catalysts were characterized by X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), temperature-programmed desorption of carbon dioxide and ammonia (TPD), BET surface area, and scanning electron microscopy (SEM). It was observed that the specific surface area, pore volume, and pore diameter of the CaO increased after being sulfonated with a 2 M sulfuric acid solution. It showed a high total surface acidity and basicity, 7.22 and 3.86 mmol/g, respectively. The optimal FFA conversion (84.94 %) from the waste cooking oil was acquired at a reaction temperature of 65 ˚C, a 9:1 MeOH: Oil molar ratio, and 5 wt% catalyst loading for a 3 h reaction time. The 2 M sulfonated CaO catalyst can be reused twice with a high FFA conversion without further treatment under optimized reaction conditions. The 2 M sulfonated CaO catalyst has potential treatment for biodiesel production from high-FFA oils due to its lower production cost and high catalytic activity.

Dolomite as A Potential Source of Heterogenous Catalyst for Biodiesel Production from Pongamia pinnata

Biodiesel production from Pongamia pinnata, a tree-based oil using healthcare industrial waste dolomite as a catalyst, was studied. The studies aimed to establish the ideal parameters for producing biodiesel, such as temperature, the ratio of methanol to oil, and the weight percentage of the catalyst. The healthcare industrial waste was procured and characterized. With the operating conditions, temperature maintained at 75°C, methanol to oil molar ratio of about 20:1, and a catalyst weight of 5%, the optimum yield of 92.3% was obtained. The tree-based nonedible oil source for biodiesel production was suggested widely due to its ability to achieve sustainable development goals (SDGs). The Pongamia Pinnata cultivation on barren land supports the afforestation projects with economic and environmental values; further biodiesel from renewable bioresources reduces emissions, and livelihood development to eradicate unemployment are the primary objectives for achieving the SDGs. The tree-based biodiesel production and adaptation of dolomite as a heterogeneous catalyst have proven to be a recent attraction among scientists. The present study is the first report on Pongamia pinnata for biodiesel production catalyzed by dolomite.

Sustainable biodiesel production from waste cooking oil using highly effective CaO/hectorite catalyst: Process optimization, kinetic and thermodynamic studies.

Biodiesel production through trans-esterification reaction requires design of efficient solid catalyst for sustainable use. This study reports a newly prepared CaO/hectorite catalyst for trans-esterification reaction of waste cooking oil (WCO). The catalyst material was prepared by wet impregnation method. Material characterization was done using various advanced instrumentation techniques such as FTIR, 1H/13C NMR, XRD NMR, BET, TGA and FE-SEM. The result of FE-SEM characterization shows the surface heterogeneity in catalytic material. Further, an enhanced BET surface area (142.3 m2 g−1) of CaO/hectorite indicated suitability of material for catalytic applications. Kissinger-Akahira-Sonuse (KAS) computational model was used to evaluate thermodynamic parameters. Response surface methodology (RSM) – Box Behnken model/ANOVA was used to draw the 3D-surface plots and 2D-contour plots for estimation of maximum biodiesel yield. The catalytic trans-esterification shows high biodiesel production (95 %) in an optimized reaction condition (10.5:1 methanol:oil molar ratio, 3.5 % catalyst loading, 57.5 °C reaction temperature and 105 min). It was found that the biodiesel produced from WCO has fuel characteristics complied with that of B100. The catalyst could be reused up to seven consecutive cycles operation resulting biodiesel production (>80 % yield) thus indicating future commercial applications in a sustainable manner.

Heterogeneization of Biodiesel Production by Simultaneous Esterification and Transesterification of Oleins

The production of biodiesel via simultaneous esterification and transesterification reactions of residual fats such as palm oleins, with variable TG and FFA composition, using methanol and methane sulfonic acid (MSA) or an acid carbon-based structured catalyst (SO3H-C) as homogeneous and heterogeneous catalysts respectively, has been investigated. The influence of various parameters, such as methanol to oil molar ratio, operating temperature, amount of catalyst, or nature and composition of the raw materials on the fatty acid methyl esters (FAME) yield was studied. It was determined that increasing the methanol to oil molar ratio resulted in an increase in the conversion of TG and FFA and a higher FAME yield; besides, reaction temperature has a strong effect. The best conditions tested to obtain the highest FAME yield (99.2%) was a methanol to oil molar ratio of 12:1, 120 °C (12 bar), a reaction time of at least 1 h, and 3% MSA as a homogeneous catalyst. The work demonstrated that an acidic solid catalyst, SO3H-C, homemade prepared, could be used as a heterogeneous catalyst in the simultaneous process under the optimized reaction conditions, achieving a complete esterification conversion with some limitations with respect to the transesterification reaction and a FAME yield close to 90.5%.

Circulation process of methyl ester production from pretreated sludge palm oil using CaO/ABS catalytic static mixer coupled with an ultrasonic clamp

This study investigates the potential of fused deposition modeling (FDM) three-dimensional (3D) printing techniques for manufacturing catalytic static mixers during biodiesel synthesis. The printed catalytic mixing elements comprises acrylonitrile butadiene styrene (ABS) plastic with 15 wt% calcium oxide (CaO) as a solid catalyst. When the reactants flowed through the CaO/ABS mixing device, the blending and acceleration processes were both significantly impacted. Moreover, their characteristics, performance in biodiesel production, reusability, and economy were analyzed. The effects of methanol to oil (M:O) molar ratio, circulation time, and sonication time on methyl ester (ME) purity were also examined. The results showed that CaO crystals were distributed on the CaO/ABS mixer’s surface, which is crucial for catalytic purposes. During circulation process of ME from pretreated sludge palm oil (PSPO), catalytic static mixer (CSM) and CSM coupled with ultrasound (CSM/US) reactors were employed. The full ultrasonic power of CSM/US reactor of 16 × 400 W (total 6400 W) was operated at 20 kHz frequency. Moreover, the continuous and pulse ultrasonic modes of CSM/US reactor were compared to determine the ME purity and electricity consumption for ME production. For the CSM reactor, 12:1 M:O molar ratio and 8.5 h circulation time were recommended to realize 94.2 wt% ME purity. For the CSM/US reactor, 12:1 M:O molar ratio and 2.25 h circulation time were recommended to achieve 96.5 wt% ME purity. Under the pulsed mode operation, ME purity of 95.09 wt% was achieved, with a reduction in electricity consumption by approximately 37.6 % compared to continuous mode operation. Furthermore, the CaO/ABS catalytic static mixer was determined to be reusable for up to three cycles in both CSM and CSM/US reactors. Thus, CaO/ABS catalytic static mixers assure high purity ME production through FDM 3D printing technology with a CaO solid catalyst.

Advancements in renewable energy: Achieving milder reaction conditions in biodiesel synthesis from green seed canola oil with pristine ZIF-8

This study explores the enhancement of reaction conditions for biodiesel production from green seed canola oil through the methanolysis reaction using pristine ZIF-8 as a catalyst. The research focused on the effects of varying the methanol-to-oil molar ratio, temperature, and reaction time as well as their combined effects on biodiesel yield. To analyze these factors, Response Surface Methodology (RSM) paired with Central Composite Design (CCD) was employed. The quadratic model was identified as the best fit for the experimental data, evidenced by a high determination coefficient (R²) of 0.99, with all model parameters proving significant. A comprehensive characterization of the catalyst was conducted using various techniques. The surface and pore properties were examined using N2 adsorption-desorption measurements. X-ray diffractometry (XRD) was employed for structural analysis, while X-ray photoelectron spectroscopy (XPS) presented the binding information of the sample. Fourier transform infrared spectroscopy (FT-IR) provided insights into the functional groups present. Thermal gravimetric analysis (TGA) assessed the thermal stability of the catalyst. Results revealed that ZIF-8 significantly improved biodiesel production, with optimal conditions identified at a reaction temperature of 160 °C, a duration of 2.5 h, and methanol to oil (M/O) molar ratio of 26, resulting in a biodiesel yield of 85 %. This yield is close to the predicted value, demonstrating the reliability of the developed model. The kinetic analysis was performed under optimal reaction conditions. From this, the activation energy (Ea) and the pre-exponential factor (A) were obtained to be 14.5 kJ/mol and 3.4×10−7 min−1, respectively. The use of pristine ZIF-8 in biodiesel production from a low-quality and cheap oil offers a more efficient and milder reaction conditions, with potential for significant reductions in production costs and environmental impact.

Utilization of Nile tilapia viscera oil and lipase as a novel and potential feedstock and catalyst for sustainable biodiesel production

The viscera of Nile tilapia, fish processing industry waste, was utilized to extract oil and lipase and used as a low-cost feedstock and catalyst, respectively, for producing biodiesel. The investigation aimed to improve the process of extracting oil from Nile tilapia viscera (NTVO) by a wet rendering method, and to use it for manufacturing biodiesel using Nile tilapia viscera lipase (NTVL)-based catalyst. Heating Nile tilapia viscera waste at 80 °C for 60 min was the best condition for oil separation, with 51.49 % oil recovery and 6.30 % yield. NTVO characteristics suggested the suitability for biodiesel production. Optimizing the synthesis of biodiesel from NTVO utilizing NTVL catalyst was also studied. The catalyst dose of 20 kUnits, reaction temperature of 35 °C, water content of 1 %, reaction period of 18 h, and methanol to oil molar ratio of 4:1 were found to provide the greatest biodiesel yield (96.9 %) (p < 0.05). ATR-FTIR analysis confirmed the conversion of NTVO to biodiesel. The physicochemical properties of biodiesel obtained met the requirement specified by international standards, namely EN 14214 and ASTM D 6751. These findings highlighted the potential of NTVO and NTVL as a substrate and catalyst for biodiesel synthesis, which might alleviate environmental pollution and disposal issues.

Optimization of biodiesel production from Croton Macrostachyus seed oil with calcium oxide (CaO) catalyst and Characterization: Potential assessment of seed and kernel

This study investigates the use of Croton macrostachyus (CMS), a widely available, fast-growing, non-edible plant common in Ethiopia’s secondary forests and less productive lands, as a biodiesel feedstock. The research compared oil yields from the seed and kernel, assessed the oxidation stability of the resulting biodiesel, and conducted transesterification using a novel combination of a CaO catalyst with methanol, which had not been explored in previous studies. Oil yield was obtained 40.8 % from the seed and 50.3 % from the kernel. Calcium oxide (CaO) was derived from eggshells through a calcination process and characterized using BET, SEM-EDX, and FTIR techniques to assess its suitability as a heterogeneous catalyst for biodiesel production. The Box-Behnken design (BBD) based on the response surface methodology (RSM) was used to optimize the reaction parameters, including reaction time (60–120 min), methanol to oil molar ratio (4:1 – 12:1), and catalyst concentration (1 % – 5 %), while the reaction temperature (60 °C) and stirring speed (450 rpm) were kept constant. Analysis of variance (ANOVA) showed that the coefficients of determination (R2 and R2 adj) were 99.42 % and 98.38 %, respectively, indicating a strong correlation between experimental and predicted values. The optimum conditions identified for maximum yield of CMS biodiesel (98.314 %) were a methanol to oil molar ratio of 8.44:1, a catalyst concentration of 2.78 %, and a reaction time of 108 min. The oxidation stability of the CMS biodiesel was obtained an induction time of 2.3 h but was enhanced to 16.17 h due to the addition of TBHQ antioxidant. All physiochemical properties were compared with ASTM D6751 and EN 14214 biodiesel standards, demonstrating that the biodiesel produced is suitable for internal combustion engine applications.

ANALISIS SIFAT FISIKA DAN SIFAT KIMIA GEL BIODIESEL DARI MINYAK BIJI PALEM PUTRI (Adonidia merrillii)

Biodiesel is an alkyl ester of long-chain fatty acids, the most common of which are methyl esters or ethyl esters. The manufacturing process involves esterification and transesterification. Traditional sources of biodiesel raw materials such as palm oil, soybeans, and jatropha have been widely studied. The princess palm, widely known as an ornamental plant, produces fruit containing seeds with quite high oil potential. This research aims to produce biodiesel and determine the physical and chemical properties from putri palm seeds. This research is experimental research with a quantitative descriptive approach. Putri palm seed oil is extracted using the soxhletation method with n-hexane solvent. The oil was then esterified using methanol with a catalyst of 1% sulfuric acid with a mole ratio of oil and methanol of 1:8 at a temperature of 60°C for 3 hours. The esterified oil is then transesterified using methanol and KOH with a methanol to oil ratio of 1:20 with KOH of 0.8% for 2 hours at a temperature of 60°C. This research has succeeded in making biodiesel from putri palm seeds. The biodiesel produced is in the form of a gel referred to as biodiesel gel with a yellowish brown color with a density of 1,236 gr/ml and a pour point of 36-38°C. The FFA/ALB value is 0.587%, the acid number is 1.177 mg KOH/g, the IOD number is 34.514 (g-I2/100 g), the saponification number is 63.19 mg KOH/g, the heating value is 48.088 MJ/Kg, and the cetane number 38,620. The IOD number, saponification number, and heating value meet the SNI standards for liquid biodiesel in general, while the cetane number and ALB value are close to SNI standards.

Transesterifikasi In Situ Minyak Biji Pepaya Menggunakan Ko-pelarut Tetrahidrofuran: Pengaruh Waktu Reaksi dan Penggunaan Katalis Natrium Hidroksida

The papaya seed oil is a non-food oil that can be used as raw material for biodiesel. The transesterification process using oil as raw material requires long process stages so it is not efficient. In situ transesterification with a co-solvent is an alternative to overcome this problem. This research aims to obtain optimum conditions for the in situ transesterification reaction of papaya seed oil with THF co-solvent. The research operating conditions included stirring speed 450 rpm, reaction at room temperature, oil:methanol molar ratio = 1:101.39, catalyst:oil molar ratio = 0.5:1, oil:THF molar ratio = 1: 67.85, reaction time are 3, 8, 13, 18, 23, 28 minutes and reactions with and without a NaOH catalyst. The best research conditions were obtained in the in situ transesterification reaction of papaya seed oil with THF co-solvent using a NaOH catalyst at a reaction time of 33 minutes, producing a crude yield of 74.38% and methyl esters concentration of 98,036.4 ppm and physical properties of biodiesel that met SNI 7182-2015, namely density 0.89 g/mL and acid number 0.44 mg KOH/g sample.

Investigation into the Fuel Characteristics of Biodiesel Synthesized through the Transesterification of Palm Oil Using a TiO2/CH3ONa Nanocatalyst

Biodiesel is a renewable and sustainable alternative fuel to petrol-derived diesel. Decreasing the operating costs by improving the catalyst’s characteristics is an effective way to increase the competitiveness of biodiesel in the fuel market. An aqueous solution of sodium methoxide (CH3ONa), which is a traditional alkaline catalyst, was immersed in nanometer-sized particles of titanium dioxide (TiO2) powder to prepare the strong alkaline catalyst TiO2/CH3ONa. The immersion method was used to enhance the transesterification reaction. The mixture of TiO2 and CH3ONa was calcined in a high-temperature furnace in a range between 150 and 450 °C continuously for 4 h. The heterogeneous alkaline catalyst TiO2/CH3ONa was then used to catalyze the strong alkaline transesterification reaction of palm oil with methanol. The highest content of fatty acid methyl esters (FAMEs), which amounted to 95.9%, was produced when the molar ratio of methanol to palm oil was equal to 6, and 3 wt.% TiO2/CH3ONa was used, based on the weight of the palm oil. The FAMEs produced from the above conditions were also found to have the lowest kinematic viscosity of 4.17 mm2/s, an acid value of 0.32 mg KOH/g oil, and a water content of 0.031 wt.%, as well as the highest heating value of 40.02 MJ/kg and cetane index of 50.05. The lower catalyst amount of 1 wt.%, in contrast, resulted in the lowest cetane index of 49.31. The highest distillation temperature of 355 °C was found when 3 wt.% of the catalyst was added to the reactant mixture with a methanol/palm oil molar ratio of 6. The prepared catalyst is considered effective for improving the fuel characteristics of biodiesel.

CCD-RSM optimization of biodiesel production from waste cooking oil using Angulyagra oxytropis and Bellamya crassa snail shell-based heterogeneous catalysts

In the present study, labuk tharoi (Angulyagra oxytropis), and ningkhabi tharoi (Bellamya crassa) were utilized to produce CaO catalyst for biodiesel production using waste cooking oil (WCO). The snail shells were calcined at a temperature of 800−1000℃ for 4 h and characterized using XRD, FTIR, BET, SEM, and EDX analysis. Central composite design-response surface methodology (CCD-RSM) was employed, and the input parameters considered for optimization were (i) catalyst calcination temperature (800−1000℃), (ii) methanol: oil ratio (molar) (6:1−12:1), (iii) catalyst loading (3−7 wt.%), and (iv) reaction temperature (55−75℃). A quadratic regression model was aliased by CCD-RSM with R2 values of 0.9291 and 0.976 for waste cooking oil methyl ester-labuk tharoi (WCOME-LT), and waste cooking oil methyl ester-ningkhabi tharoi (WCOME-NT) models indicating a good fit. An optimum biodiesel yield of (95.87, 95.91 %) was obtained at catalyst calcination temperature (891, 886℃), methanol to oil molar ratio (9.89:1, 9.67:1), catalyst loading weight % (7, 7 wt.%), and reaction temperature (75, 75℃) for WCOME-LT and WCOME-NT model respectively. The calcination temperature has a major impact on the biodiesel yield as per analysis of variance. The catalyst reusability was up to four cycles with a biodiesel yield of more than 83 %.

Direct application of tungstosilicic acid hydrate for the treatment of high free fatty acid in acidic crude palm oil and for biodiesel production

AbstractThis study explored the use of industrial acidic crude palm oil (ACPO) for biodiesel production, facing a significant obstacle due to its high free fatty acid (FFA) content, which complicates the biodiesel production process. Typically, esterification is employed to convert FFAs into fatty acid methyl ester (FAME). Herein, the effectiveness of tungstosilicic acid hydrate (TSAH) as an unsupported heteropoly acid (HPA) catalyst for FFA esterification in ACPO was investigated. The FFA content was reduced from 8.43% to 0.95% under optimum conditions (4 wt% catalyst dosage, a methanol to oil molar ratio of 10:1, 150 min and a temperature of 60°C). Noteworthy, the TSAH catalyst showed stability over 7 cycles. The kinetic analysis revealed that the FFA esterification process closely followed pseudo first‐order kinetics, with an R2 value of 0.94. Furthermore, the biodiesel produced from TSAH‐treated ACPO meets the standard specifications outlined by ASTM D6751 and EN 14214. This research highlights the effectiveness of TSAH in catalyzing FFA esterification without the need for additional support materials or modifications.

Electrolysis combined with magnetic CeO2/ZSM-5@Fe3O4 catalyst to boost transesterification for biodiesel production

The current transesterification for biodiesel is normally conducted with heat input and the resource is required to remove the contained water, which is complicated and costly. The novel magnetic catalyst of the bimetallic oxides of CeO2 and Fe3O4 supported on the hierarchical pore ZSM-5 was prepared and used for the biodiesel production through transesterification of palm oil with methanol under the electrolytic assistance. The prepared catalysts were characterized by SEM-EDS, TEM, FTIR, XRD, CO2/NH3-TPD, N2 adsorption–desorption and VSM, etc. The loaded cerium stimulated the particles growth and abundant catalytic active sites were obtained due to the coral-like structure and they were beneficial for transesterification. The presence of both acidic and basic sites guaranteed the strong catalytic capability of the CeO2/ZSM-5@Fe3O4 catalyst. Under the optimized transesterification condition of the catalyst dosage of 3 wt%, methanol to oil molar ratio of 18:1, reaction time of 2.5 h, electrolysis voltage of 40 V, presence of 2 % wt/wt of water added and reaction temperature of 25 ℃, the FAME yield of approximately 95 % was achieved. Also, the catalyst showed an acceptable reusability, where the FAME yield of 79 % was obtained after fourth reused cycle. In conclusion, the water in the resource promotes the electrolytic transesterification to occur efficiently at the room temperature.

Artificial neural network framework for the selection of deep eutectic solvents promoted enhanced oil recovery by interfacial tension reduction mechanism

Estimation of interfacial tension (IFT) and % reduction in IFT of Brazil and China regions’ heavy crude oil is employed by Artificial Intelligence (AI) led frameworks. The uniqueness of proposed approach lies in using AI frameworks that are constructed using Artificial Neural Network (ANN) and meta-heuristic algorithms i.e. Genetic Algorithm (GA) and Grey Wolf Optimization (GWO) forms three AI frameworks namely ANN, ANN-GA, and ANN-GWO is employed for IFT estimation of heavy oil and deep eutectic solvent-brine interface. The hyper-parameters of the frameworks are trained, validated, and tested over 18228 IFT data points obtained from the Omani heavy crude oil. The intermolecular interactions between oil, brine, and DES are obtained by generating surface segments in COnductor like Screening MOdel for Real Solvent (COSMO-RS) framework. The composition of brine, mole ratio of oil, DES, and temperature are other input parameters for AI model. The IFT estimation leads to the selection of 3 hydrophilic DESs capable of greater than 75 % IFT reduction and 14 hydrophilic DESs capable of 50–75 % IFT reduction. ANN-GWO scores best AI framework among 3 whereas ANN-GA fails to estimate IFT reduction greater than 50 %. Analysis of IFT with respect to mole fraction reveals the most suitable range of DES addition for IFT reduction.