Efficient Biodiesel Production Research Articles

Sulfonic-acid-functionalized lignin-derived LC900@SO3H: A promising catalyst for the efficient production of biodiesel via the esterification of oleic acid

The renewable and clean biodiesel production makes higher demands for cheap, green and efficient catalysts. A sulfonic-acid-functionalized LC900@SO3H catalyst was prepared using alkali lignin as the carbon source, which was applied in the esterification of oleic acid to produce biodiesel. The yield of biodiesel reached 96.3% under mild conditions (Temperature = 95 ◦C, Catalyst dosage = 3.5wt%, MeOH/Oleic acid = 11.2:1, Time = 1.5h). The catalysts were reused at least 3 times with a high biodiesel yield of over 80%. The morphological and spectral analyses of the catalysts were conducted using BET, TGA, Raman, SEM, FTIR, and XPS, and the products were analyzed by GC and GC-MS. Characterizations indicated that the huge specific surface area (1618.68 m2/g) and large pore volume (0.8573 cm3/g) endow the LC900@SO3H with abundant sulfonic-acid-functionalized active sites for excellent catalytic activity. In addition, the response surface method (RSM) revealed the interaction of different reaction conditions for biodiesel production. The cost of 1kg catalyst was estimated as $3.59, showing good economic viabilities.

Hierarchical micro-meso-macroporous xAIL@HP UIO-66-NH2 catalysts used for efficient biodiesel production from low-grade acidic oils

The utilization of hierarchical porous supports to fabricate an efficient solid catalyst is a feasible strategy due to their remarkable merit in ameliorating the diffusion of reactants on the catalyst surface and increasing the exposure of active species in particular for the bulky molecule-involving reactions. In this research, to abatement the mass transfer resistance of large triglycerides, the hierarchical porous solid catalyst (xAIL@HP UIO-66-NH2) was prepared by grafting acidic ionic liquid (AIL) with double acidic sites of -SO3H and HSO4- onto micro-meso-macroporous metal-organic gels (HP UIO-66-NH2) through acid-base interactions between -NH2 moiety of HP UIO-66-NH2 and acidic moiety of AILs. The catalyst characterization results showed that the xAIL@HP UIO-66-NH2 catalyst owned the hierarchical porous structure and double Brønsted-Lewis acid centers with large BET surface area and pore volume. This catalyst was adopted for efficient biodiesel production from low-grade acidic oils, exhibiting high catalytic activities for triglyceride transesterification and free fatty acid (FFA) esterification reactions. By using acidic oils as feedstocks, the oil transesterification conversion could reach 91.3 % and the FFAs were completely converted to biodiesel under the conditions of 130 °C for 8 h at methanol-to-oil molar ratio of 35: 1 and catalyst dosage of 8 wt%. Based on the kinetic study, the activation energy Ea of this catalyst was 56.6 kJ/ mol, and the reaction complied with pseudo-first-order kinetics. This solid catalyst demonstrated satisfactory acid and water resistance, with good reusable performance, posing great potential in the efficient biodiesel preparation by the one-pot method using the low-grade acidic oils.

Optimization of microwave-assisted biodiesel production using response surface methodology

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

Olfactory Profile and Stochastic Analysis: An Innovative Approach for Predicting the Physicochemical Characteristics of Recycled Waste Cooking Oils for Sustainable Biodiesel Production

The efficient, economical, and sustainable production of biodiesel from waste cooking oils (WCOs) depends on the availability of simple, rapid, and low-cost methods to test the quality of potential feedstocks. The aim of this study was to establish the applicability of stochastic modeling of e-nose profiles in the evaluation of recycled WCO characteristics. Olfactory profiles of 10 WCOs were determined using a Sensigent Cyranose® 320 chemical vapor-sensing device with a 32 sensor-array, and a stepwise multiple linear regression (MLR) analysis was performed to select stochastic parameters (explanatory variables) for inclusion in the final predictive models of the physicochemical properties of the WCOs. The most important model parameters for the characterization of WCOs were those relating to the time of inception of the e-nose signal “plateau” and to the concentration of volatile organic compounds (VOCs) in the sensor region. A comparison of acid values, peroxide values, water contents, and kinematic viscosities predicted by the MLR models with those determined by conventional laboratory methods revealed that goodness of fit and predictor accuracy varied from good to excellent, with all metric values >90%. Combining e-nose profiling with stochastic modeling was successful in predicting the physicochemical characteristics of WCOs and could be used to select suitable raw materials for efficient and sustainable biodiesel production.

Methyl ester production process from palm fatty acid distillate using hydrodynamic cavitation reactors in series with solid acid catalyst

This study aims to optimize the reduction of free fatty acids (FFAs) in palm fatty acid distillate (PFAD) using hydrodynamic cavitation reactors (HCRs) in series and a solid acid catalyst for biodiesel production. Hydrodynamic cavitation is used to accelerate the esterification of FFAs using a heterogeneous acid catalyst. There are three HCRs units, and each HCR composed of a 3D-printed rotor and stator, is separated by flanges and equipped with a basket for holding Amberlyst-15 catalyst. Through response surface methodology (RSM), the esterification process is optimized by adjusting its optimal parameters, namely, methanol (2–12 wt%), circulation time (30–170 min), and rotor speed (1000–3000 rpm). The optimal conditions for achieving a maximum methyl ester purity of 89.76 wt% in converting FFA in first-step esterified oil are 9 wt% methanol (molar ratio of methanol to oil of 4:1), 133 min of circulation time, and 2000 rpm of rotor speed. An 82.48 wt% biodiesel yield is achieved from the HCRs in series under the optimal conditions. Scanning electron microscope images reveal that after the esterification process, there are minor cracks and defects on the catalyst’s resin surface, indicating the presence of residual reactants. Further examination of the catalyst after the esterification process, reveals an average absorption pore diameter of 341.41 Å and BET surface area of approximately 41.68 m2/g. Although there were slight physical changes in the catalyst, HCRs technology offers a viable FFA reduction process that could enhance biodiesel production efficiency. Moreover, the optimized conditions achieved in this study contribute to the advancement of biodiesel production processes and provide insights into the performance of the catalyst used.

Basicity-tuned graphitic carbon nitride supported MgO heterogeneous catalysts for efficient transesterification of groundnut oil to biodiesel

Quality and quantity of biodiesel derived from oil depend on the type of feedstock and the transesterification process. To maximize biodiesel production efficiency and ensure the desired fuel quality, it is crucial to develop and optimize feedstock-specific production processes. This study reports on the transesterification of groundnut oil using a heterogeneous catalyst. Magnesium oxide (MgO) and its composites with graphitic carbon nitride (g-C3N4) at 10, 30, and 50 wt% (MG10, MG30, MG50) were used. The composite catalyst combines basic sites from MgO and Lewis acid sites from the nitrogen atoms in the g-C3N4 triazine unit, giving rise to synergistic effects that enhances biodiesel production. MgO nanoparticles were synthesized via precipitation, followed by calcination at 500 °C, and MgO/g-C3N4 composites were prepared by grinding at different ratios. Morphological and structural studies confirmed material characteristics. BET analysis indicated an increased surface area of 71.39 m2/g, enhancing catalytic activity, while SEM revealed the agglomerated g-C3N4 and the cubic morphology of MgO. Response surface methodology was used to optimize catalyst loading, temperature, and reaction time parameters. The optimal conditions for biodiesel conversion using MG50 composite was determined to be methanol/oil ratio of 6:1, 2.5 wt% catalyst loading, 41.7 °C reaction temperature and spanning 52 min of reaction, yielding 94 % efficiency. GC–MS analysis confirmed successful transesterification, identifying key fatty acid esters such as ethyl oleate (34.72 %) and hexadecanoic acid methyl ester (7.69 %). This work supports further research into feedstock-specific catalysts for industrial biodiesel applications.

Recent Advances in Magnetic Nanoparticle-Based Heterogeneous Catalysts for Efficient Biodiesel Production: A Review

Recent Advances in Magnetic Nanoparticle-Based Heterogeneous Catalysts for Efficient Biodiesel Production: A Review

Heteropolyacid and Lithium Infused Calcium Oxide Catalyst for Biodiesel Production from Food Waste

The advancement of mixed metal oxide catalysts has attracted considerable attention among various workers. Supported MoOx catalyst materials possess more Lewis and Brønsted acid functionalities which assist in the efficient biodiesel production. In this study, ammonium molybdate and Li+ were loaded over eggshells-derived calcium oxide to transesterify the frying oil/waste cooking oil (WCO) to produce biodiesel/fatty acid methyl ester (FAME). Characterization techniques i.e., X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis were employed to confirm the material. The surface modelling predicted the transesterification reaction parameters. The optimal condition to transesterify WCO with synthesized Mo/Li/CaO catalyst was 6 wt.% catalyst dose, 13.70:1 ratio of methanol:oil (m/o), time of 1 h and 60 ºC temperature. The optimum FAME yield of 97% was observed. The gas chromatography-mass spectroscopy (GC-MS) and other spectroscopic techniques were used to analyze produced FAME. The reusability of catalyst was good and the catalyst can be reutilized effectively up to a limit of 5 runs. By leveraging this innovative catalyst derived from eggshells, this study contribute to a more sustainable and cost-effective biodiesel production process.

Application of Catalysts Used in Biodiesel Production - A Review

Biodiesel stands as a promising alternative to traditional fossil fuels for transportation, boasting renewability, biodegradability, and environmental friendliness. However, the efficiency of biodiesel production hinges on the catalytic processes that expedite the crucial transesterification reaction between triglycerides and alcohols. The choice of catalyst becomes a multifaceted decision, influenced by factors such as feedstock quality, specific reaction conditions, and the environmental footprint associated with the catalyst itself. This comprehensive paper deals the current state of catalysts employed in biodiesel production, offering readers a nuanced understanding of the subject. The catalyst landscape is explored through an intricate analysis of various types, encompassing homogeneous, heterogeneous, enzymatic, nano, and bio-derived catalysts. A critical component of the paper is the exploration of recent advancements in catalyst synthesis techniques. This includes an assessment of the performance of these novel catalysts, elucidating their potential contributions to enhancing the biodiesel production process. By offering insights into the future prospects of these catalysts within the context of biodiesel production, the paper contributes to the evolving discourse on sustainable energy sources. In pursuit of its overarching goal, the paper aspires to furnish readers with more than just an up-to-date overview; it aims to provide a thorough examination of the prevailing trends and challenges in the realm of catalyst utilization for biodiesel production. As the world seeks greener alternatives, this paper offers valuable insights that extend beyond the present, fostering a deeper understanding of the dynamics shaping the future of biodiesel production and sustainable transportation.

Optimization of oil extraction from Melia azedarach fruits using methanol-modified SC-CO2 for highly efficient biodiesel production using a modified LAC catalyst

A highly efficient oil extraction method including modified Supercritical carbon dioxide (SC-CO2) with co-solvents was applied for oil extraction from Melia azedarach fruits and then using a modified LAC (luffa activated carbon) catalyst, the oil was converted to biodiesel for the first time. The effect of pressure (22–30 MPa), temperature (40–80 °C), extraction time (0–240 min) and co-solvent (methanol and n-hexane) were determined on SC-CO2 extraction to obtain the optimum condition. The optimum extraction conditions for Melia azedarach oil corresponded to a pressure of 30 MPa and temperature of 40 °C at 180 min using methanol as of co-solvent. The maximum yield was obtained by addition of methanol as co-solvent in an amount of 10 %, w/w. The methanol- modified SC-CO2 extraction oil yield was 43 % (w/w) and the oil yield by n-hexane-modified SC-CO2 extraction was 38 %, while the oil yield obtained by pure SC-CO2 extraction was 32 %. Then, the effect of catalysts LAC-NH2 and LAC-N(Et)2 as safe, economical, free-metal, and less time-consuming heterogeneous catalysts was investigated on biodiesel production from extracted oil. The results revealed that the optimum yields of 98 % was obtained for biodiesel production using 2 wt% of LAC-NH2 catalyst at the reaction conditions of oil to methanol ratio of 1:6, reaction temperature of 60 °C, and reaction time of 3 h.

Biomass to biofuel: Palm kernel shells as catalyst supports for enhanced biodiesel production

AbstractThe use of agricultural biomass fibers, specifically palm kernel shell (PKS), has significant potential to enhance biodiesel production. This approach overcomes economic barriers and contributes to sustainability by repurposing agricultural biomass. This study explores the effectiveness of PKS as a cost‐effective and sustainable catalyst support. Palm kernel shell was chosen due to its high carbon content, low ash presence, and abundance as a byproduct in the palm oil industry, making it an economically viable and environmentally friendly option. In this study, an optimized activated carbon from PKS biomass was fabricated as catalyst support to enhance biodiesel production efficiency. Using response surface methodology (RSM), the PKS was impregnated with phosphoric acid and synthesized at various acid concentrations, impregnation times, and activation times to enhance porosity for catalytic support capabilities. The experimental design included a central composite design (CCD) to vary these factors systematically and determine their optimal levels. Scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) analysis revealed significant development of porosity, affirming the efficient activation process. Energy dispersive X‐ray (EDX) analysis confirmed phosphorus incorporation during activation, indicating the formation of an intricate pore structure. Fourier transform infrared (FTIR) spectroscopy highlighted the presence of functional groups pertinent to the biodiesel reaction process. The transesterification process employing PKS as a catalyst with different biobased feedstocks, such as waste frying oils from corn, palm, and sunflower, led to biodiesel yields of varying efficiencies. Notably, corn oil had the highest yield at 94.92%. This study highlights the potential of PKS as a biobased catalyst support and contributes to the broader biorefinery concept by integrating biomass utilization into renewable fuel production.

Biomass-incorporated KNO3-C/γ-Al2O3 bifunctional catalyst for efficient biodiesel production

Biodiesel has gained attention as a promising renewable and sustainable alternative to fossil fuels, which necessitated the development of an effective and eco-friendly catalyst for transesterification processes. Herein, this research reported the development of a highly efficient bifunctional catalyst by incorporating carbon from oil palm leaves (OPLs) into KNO3/γ-Al2O3 catalyst, synthesized through a facile method, to concurrently catalyze the waste cooking oil (WCO) transesterification and free fatty acids (FFAs) esterification in a one-pot reaction. Proposed Box-Behnken Design (BBD) model's ideal conditions, experimentally yielded an average of 93.74 % biodiesel yield. Meanwhile, analysis revealed that the catalyst with 30 wt% KNO3 loadings and 1.0 g oil palm leaves dosage (OPLD), calcined at 700 °C, has a BET surface area of 46.93 m2/g and exhibited the presence of K2O, K2O2 and K2C2 active species on the catalyst surface. In addition to exhibiting high total basicity and acidity of 2.9 mmol/g and 2.1 mmol/g, respectively, environmental studies suggested this catalyst generated less waste, highlighting its significant potential of being used for efficient biodiesel production. Therefore, present research introduces a new approach for synthesizing a fruitful and ecofriendly bifunctional catalyst to attain one-pot biodiesel production from low-grade oils.

Efficient biodiesel production by sulfonated carbon catalyst derived from waste glycerine pitch via single-step carbonisation and sulfonation

Glycerine pitch is a highly alkaline residue from the oleochemical industry that contains glycerol and contaminants, such as water, soap, salt and ash. In this study, acidic heterogeneous glycerol-based carbon catalysts were synthesised for biodiesel production via single-step partial carbonisation and sulfonation using pure glycerol and glycerine pitch, producing products labelled as SGC and SGPC, respectively. Carbon materials were obtained by heating glycerol and concentrated sulfuric acid (1:3) at 200℃ for 1 h. The produced SGC and SGPC displayed high densities of sulfonic group (–SO3H), i.e. 1.49 and 1.00 mmol·g−1, respectively, alongside carboxylic (–COOH) and phenolic (–OH) acid. In the catalytic evaluation, excellent oleic acid conversions of 96.0 ± 0.4 % and 92.4 ± 0.5 % were achieved using SGC and SGPC, respectively, under optimised reaction conditions: 1:10 M ratio of oleic acid to methanol, 5 % (w/w) catalyst, 64℃ and 5 h. SGPC was found to be recyclable with 68.5 % conversion after the 6th cycle, which was attributed to the loss of –SO3H and catalyst deactivation by the deposition of oleic acid on its surface. Remarkably, despite the impurities present in the glycerine pitch, the obtained results demonstrated that the reactivity of SGPC is comparable to SGC and superior to that of commercial solid acid catalysts, which demonstrated that the presence of impurities appears to have minimal impact on the production of carbon materials and their properties.

Synergistic effect of La2O3-Al2O3 based catalysts for efficient biodiesel production

Comprehensive synergistic effect of La2O3-Al2O3 on the catalytic performance of transesterification reaction of palm oil with methanol for biodiesel production was studied. The prepared catalyst possessed bifunctional acid-base properties. The well-balanced of acido-basic sites amounts over the catalyst at the La2O3 loading of 40 % and the calcined temperature of 600 °C gave the maximum fatty acid methyl ester (FAME) content of 93.12 %, under the optimum conditions of 1:30 molar ratio of oil to methanol, 200 °C reaction temperature, 39 bar reaction pressure, 5 wt% catalyst loading and 5 h reaction time. The catalyst exhibited reasonable stability. The partial leaching of La3+ ions and deposition of organics resulted in the loss of activity. The results showed that the catalyst generated new weak basic sites and more effective in the transesterification compared to strong basic sites as reported previously. The different strengths of new acid sites were also formed. The balancing of acid-base sites amount was a key to control the catalytic activity and the formation of side reactions. This gives critical guidance in further catalyst development for biodiesel production of waste oils or low-quality oils via simultaneous esterification and transesterification, which helps the biodiesel system being economical and scalable.

Adaptive state feedback controller design for efficient biodiesel production under kinetic uncertainty

In this study, we optimize the quality and economic performance of biodiesel production through a scenario-based adaptive state feedback control framework. Our goal is to maximize the operational efficiency while ensuring the production of on-spec biodiesel, despite uncertainties in reaction kinetics. A first-principle model is employed to describe the process dynamics, with kinetic parameters estimated online using a moving horizon estimator (MHE). A pool of state feedback controllers is created via off-line nonlinear optimization and metaheuristic algorithm based on sampled kinetic scenarios. Then, the uncertainty space is partitioned into several clusters, each linked to an optimal controller from the pool. During online operation, the appropriate controller is selected by matching the estimated kinetic parameters to the corresponding cluster. Simulation studies on a semi-batch reactor demonstrate that manipulating the methanol feed flow rate and heat duty with our control approach significantly improves operational efficiency, reduces online computational time, and enhances robustness to kinetic uncertainties compared to model predictive control (MPC).

Sustainable biodiesel production via castor oil transesterification using organotin(IV) compounds as catalysts

The rapid reduction in fossil fuel reserves and their environmental effects has caused a serious threat to humanity. Meanwhile, the exponential increase in the usage of fossil fuels demands the exploration of new energy sources. Therefore, this work was designed keeping in view the today need of the World for renewable energy source. The 4-(4-chloro-2-fluorophenylamino)-4-oxobut-2-enoic acid based organotin(IV) carboxylates were prepared and characterized by FT-IR, NMR and single crystal XRD analysis. Due to the Lewis acid character of Sn(IV) centre confirmed by DFT computational study, the synthesized compounds were used as catalysts for the transesterification of castor oil for biodiesel production. Under the optimized experimental conditions, the catalytic performance of the tested compounds was found as follow: 1 > 3 > 2 > 4 > 6 > 5 > 7. The obtained biodiesel was confirmed by FT-IR, NMR and GC–MS. The fuel properties of the obtained biodiesel were also determined and compared with American Standard (ASTM D-6751). Based on their catalytic performance, these compounds might be the potential future candidates for the expansion of catalyst systems for efficient biodiesel production from the various feedstocks.

Glycerol-Free Biodiesel via Catalytic Interesterification: A Pathway to a NetZero Biodiesel Industry

Conventional biodiesel manufacturing uses alcohol as an acyl acceptor, resulting in glycerol as a side product. The increased demand for biodiesel has led to the production of a substantial surplus of glycerol, exceeding the market need. Consequently, glycerol is now being regarded as a byproduct, and in some cases, even as waste. The present study aims to suggest an economically viable and ecologically friendly approach for maintaining the viability of the biodiesel sector. This involves generating an alternative byproduct of higher value, rather than glycerol. Triacetin is produced through the interesterification of triglycerides with methyl acetate, and is a beneficial ingredient to biodiesel, reducing the need for extensive product separation. The primary objective of this research is to improve the interesterification reaction by optimising process parameters to maximise biodiesel production while using sulphuric acid as an economically viable catalyst. The study utilised the Box–Behnken design (BBD) to investigate the influence of various process variables on biodiesel yield, such as reaction time, methyl acetate to oil molar ratio, and catalyst concentration. An optimisation study using Response Surface Methodology (RSM) focused on key process reaction parameters, including the methyl acetate to oil (MA:O) molar ratio, catalyst concentration, and residence time. The best conditions produced a biodiesel blend with a 142% yield at a 12:1 MA:O molar ratio, with 0.1 wt% of catalyst loading within 1.7 h. The established technique is deemed to be undeniably effective, resulting in an efficient biodiesel production process.

Design and Development of p-toluenesulfonic acid Functionalized Dual-functional Fe-MOF@SBC Heterogeneous Catalyst for Efficient Biodiesel Production and Photocatalytic Degradation of Metronidazole

Design and Development of p-toluenesulfonic acid Functionalized Dual-functional Fe-MOF@SBC Heterogeneous Catalyst for Efficient Biodiesel Production and Photocatalytic Degradation of Metronidazole

Hypercrosslinked porous polymer as catalyst for efficient biodiesel production

While porous organic polymers (POPs) are known for their unique properties, their application in basic biodiesel catalysis is innovative. This study introduces a novel catalyst, hypercrosslinked polymer (HCP-SB-K), synthesized through mechanochemical polymerization of styrene and benzaldehyde with a cross-linking agent and FeCl3, followed by calcination of the previous polymer impregnated with KNO3. The synthesis costs 3.328 euros per gram of catalyst, covering energy and reagent expenses. The catalyst's basic character is explored, demonstrating efficient transesterification with diverse feedstocks. Under optimal conditions, the HCP-SB-K catalyst exhibits exceptional catalytic activity, yielding 99.9% FAME (Fatty Acid Methyl Esters) at 60 °C, 2 h and 3% w/w catalyst. Investigation of free fatty acid (FFA) content highlights the catalyst's effectiveness with oils varying FFA levels: oils with acid value of 0.44 mgKOH goil−1 reached 92.1% FAME at 60 °C, 1 h and 3% w/w catalyst; oils with an acid value of 1.11 mgKOH goil−1, reached 75.9% FAME, under the same conditions. Catalyst leaching evaluation indicates no discharge of basic sites. The regenerated catalyst (impregnation with KNO3 and calcination, after the first use) exhibits a 98.2% FAME like the fresh catalyst. This suggests that HCP-SB-K can be regenerated without noticeable deactivation, emphasizing its industrial potential.

Engineering the Band Gap of a g-C3N4 Catalyst by the Incorporation of Organic Acid for Efficient Biodiesel Production

Engineering the Band Gap of a g-C₃N₄ Catalyst by the Incorporation of Organic Acid for Efficient Biodiesel Production