Generation Biodiesel Research Articles

Biodiesel production from the transesterification of waste cooking oil via CaO/HAP/MnFe@K magnetic nanocatalyst derived from eggshells and chicken bones: Diesel engine and kinetic studies

This study focuses on the biodiesel generation from waste cooking oil (WCO) utilizing eggshells/chicken bones-derived magnetic nanocatalyst (CaO/HAp/MnFe@K). Various assessments were applied to demonstrate the CaO/HAp/MnFe@K nanocatalyst surface. These assessments showed that CaO/HAp/MnFe@K nanocatalyst has considerable catalytic attributes (e.g., highly crystalline, suitable surface area, and favorable porosity). The highest biodiesel efficiency employing CaO/HAp/MnFe@K magnetic nanocatalysts was 99.10%, which was obtained at a molar proportion of 15.24:1, catalyst content of 2.97 wt.%, reaction time of 175.72 min, and temperature of 67.72 °C (optimal conditions). Further, the reaction kinetics demonstrated that the transesterification of WCO in the attendance of CaO/HAp/MnFe@K nanocatalyst follows the pseudo-first-order model. Besides, the activation energy and exponential factor reflection reveal that the conversion of WCO to biodiesel is 41.51 kJ/mol and 1.66×105 min-1, respectively. By adding WCO-derived biodiesel to diesel, the release of carbon dioxide (CO2) and nitrogen oxides (NOx) increases while the carbon monoxide (CO) and unburned hydrocarbon (UHC) amounts diminish. By boosting biodiesel in the fuel combination, the quantities of brake specific fuel consumption (BSFC) and exhaust gas temperature (EGT) increased while the Brake Thermal Efficiency (BTE) amount decreased. Moreover, reusability of the CaO/HAp/MnFe@K nanocatalyst revealed that the magnetic particles were considerably stability.

Valorization of dairy waste scum oil and rice husk ash-supported CuO nanocatalyst towards cleaner production of biodiesel: A waste-to-energy approach

This study surveys the valorization of dairy waste scum oils (DWSO) to synthesis biodiesel using a novel rice husk ash-supported CuO nanocatalyst. The rice husk ash-supported CuO nanocatalyst was synthesized through a facile impregnation method and characterized by BET, XRD, FTIR, EDX, CO2/TPD, TEM, and FESEM to confirm its structural and morphological features. Transesterification of DWSO was conducted under optimized conditions, achieving a maximum biodiesel yield of 97.42% at temperature of 62.36°C, methanol/DWSO proportion of 11:12, and nanocatalyst loading of 2.76wt.% within 2.85h. Kinetic studies revealed that the transesterification reaction follows a pseudo-first-order model with an activation energy of 100.34kJ/mol. Thermodynamic analysis indicated that the reaction is endothermic (ΔH = 100.26kJ/mol) and non-spontaneous (ΔG = -11043.6kJ/mol) at the studied temperature range, suggesting the requirement of external heat to drive the process. Reusability tests demonstrated that the rice husk ash-supported CuO nanocatalyst retains over 86% of its initial activity after seven cycles, highlighting its potential for practical applications. This study highlights the dual benefits of utilizing agro-industrial waste for both feedstock and catalyst support, promoting a cleaner and economically viable approach for biodiesel generation.

Valorization of marble sludge waste in biodiesel production using a central composite design.

This work addresses the scarcity of energy resources and environmental issues by concentrating on the synthesis of biodiesel by the transesterification of waste cooking oil with methanol. Marble sludge (MS), a novel heterogeneous catalyst, was used to speed up the rate of reaction. The catalyst's physical and chemical characteristics were thoroughly examined using a variety of methods, including X-ray diffraction, X-ray Fluorescence, SEM, particle size distribution, and BET analysis. Using the MS catalyst, the study investigated the impact of important parameters on the yield of biodiesel from waste cooking oil with the aid of response surface methodology using Design-Expert version 13 software. These parameters included temperature (50-70℃), reaction time (1-4h), catalyst concentration (1-5 wt%), and methanol-to-oil molar ratio (5-20mol/mol). Optimization of the parameters was performed for economic targets to lower the production cost of biodiesel. The results showed that a methanol-to-oil molar ratio of 20:1, a catalyst of 5 wt%, and a reaction time of 1h at 57℃ were the ideal parameters for obtaining a biodiesel yield of 93.5%. The resultant biodiesel revealed promising characteristics, such as a flash point of 160℃, a kinematic viscosity of 4 mm2/s, and a density of 0.871g/cm3. The study demonstrates the significant consequences and real-world advantages of using rational engineering methods to use MS as a very effective, stable, and easily recoverable catalyst for the long-term, sustainable generation of biodiesel from waste cooking oil.

Concurrent conversion of waste cooking oil using Al metal-organic framework and subcritical methanol through esterification/transesterification process

Recently, some scientists have focused on discovering techniques for manufacturing biodiesel on a significant, efficient, and ecologically sustainable scale. Choosing a catalyst is a notable challenge due to the instability and cost feasibility issues connected with newly designed homogeneous and heterogeneous catalysts. This paper describes the synthesis and utilization of aluminum-based metal-organic frameworks (MOFs) as catalysts for the generation of biodiesel from waste cooking oil (WCO). The processes involved in this study are esterification and transesterification, which are carried out using subcritical methanol. The catalyst analysis reveals that the MOFs possess a filamentous structure, with a crystallite size ranging from 300 to 500 nm. Furthermore, these MOFs exhibit thermal stability up to 470 °C. The catalyst underwent examination for biodiesel production from waste cooking oil (WCO), and the resulting biodiesel samples met the standards set by the American Society for Testing and Materials (ASTM). The experiment was devised and fine-tuned to incorporate the three independent variables using a multilevel factorial design, response surface methodology, and a three-way analysis of variance (ANOVA). The FAME conversion peaked at 91.96 %, as determined through statistical analysis of the optimization findings. The corresponding values for the variables were X1: 423.15 K, X2: 1800s, and X3: 28 mol/mol. Based on ANOVA statistics, the experimental and mathematical verification demonstrates a fair correlation between the actual and calculated catalyst performance. The temperature and molar ratio of methanol: WCO significantly affected the FAME conversion.

Effects of different gas energy shares on combustion and emission characteristics of compression ignition engine fueled with dual-fossil fuel and dual-biofuel

This study systematically investigates the energetic and environmental performance of a four-cylinder compression ignition (CI) engine fueled by gaseous and liquid dual-fuel (D-F), utilising various combinations of fossil fuels and biofuels. Fossil diesel or pure hydrotreated vegetable oil (HVO) – new generation biodiesel was used as the pilot fuel to initiate ignition of the gaseous fuel. The gaseous fuels used were natural gas (NG) and simulated biogas (BG) composed of 60 % NG and 40 % CO2 by volume, injected into the intake manifold at varying gas energy shares (GES) of 40 %, 60 %, and 80 %. Reference values were provided from conventional combustion of diesel fuel and HVO. This study used numerical simulations to examine indicators of combustion, such as ignition delay, premixed combustion phase, diffusion combustion phase, and subsequent combustion phases, across diverse fuel combinations. Within lean dual-fuel mixtures, when the gaseous fuel remained below the flammability threshold, the peak pressure was diminished, the rate of pressure rise was lowered, and the combustion process decelerated, facilitating a faster transition to the diffusion phase. As the engine load and GES increased, the excess air ratio decreased, bringing the air-fuel mixture closer to the flammability limit, which in turn altered the combustion characteristics and engine performance trends. Combustion with increasing BG content showed partial similarities to that of NG, though the high CO2 content in biogas was found to suppress combustion, functioning similarly to an exhaust gas recirculation. The study also compared brake thermal efficiency (BTE), as well as specific emissions of CO, HC, NOX, CO2, and smoke for the D-F engine operation against pure diesel and HVO at different loads and GES levels. Additionally, an overlimit function was used to assess the emission levels of D-F engines with reference to emission limits.

WITHDRAWN: rGO@CaO/NiO as a bifunctional heterogeneous nanocatalyst for high-quality biodiesel production from degraded waste oil by microwave-assisted: Diesel engine parameters assessment

In this research, a highly effective rGO@CaO/NiO bifunctional nanocatalyst was synthesized and utilized for the generation of biodiesel from degraded waste oil (DWO) through microwave assistance. A comprehensive analysis was conducted to assess the catalyst structure, revealing a notable specific surface area with significant surface characteristics for the rGO@CaO/NiO bifunctional nanocatalyst. The maximum biodiesel yield was achieved 97.46% under optimum conditions including methanol to oil ratio of 11.1 mol/mol, catalyst content of 3 wt.%, microwave time of 7.5 min, and stirring speed of 700 rpm. The catalyst's reusability was demonstrated through multiple cycles, maintaining high stability and consistent biodiesel yield over seven iterations. The activation energy and exponential factor for the conversion of DWO to biodiesel were determined as 30.91 kJ/mol and 2.3×104 min-1, respectively. The physical attributes of DWO-derived biodiesel revealed that they fall within the ASTM D6751 standard range. The impact of adding biodiesel to petrodiesel/biodiesel blends at various torques on the emission of key pollutants (CO, NOx, CO2, and UHC) and engine performance (BP, EGT, BTE, and BSFC) was investigated, yielding promising results. The rGO@CaO/NiO appears as a superior choice for biodiesel production, offering exceptional reusability, and significant biodiesel efficiency achieved within a short reaction time.

A comprehensive techno-eco-environmental investigation of an efficient biodiesel generation procedure through hydrodynamic cavitation

The growth of cleaner biodiesel generation associated with hydrodynamic cavitation from canola oil via transesterification is acquiring prominence owing to considerably descending energy needs and time. In this work, the conversion of canola oil into biodiesel and glycerol was achieved through the process of transesterification with methanol, employing sodium hydroxide as a catalyst. The newly offered process was investigated from technical, economic, and environmental points of view, and the precision of the results was verified and accepted compared to previously published works. The technical results revealed that the maximum exergy destruction rates as well as exergy efficiency belonged to the transesterification process. The economic study showed that the capital cost of the process was 638.7 MUSD/year. Also, the return period was computed less than 4 years. Moreover, comparison analysis proved that Canola oil proved to be a more advantageous primary material for the production of biodiesel and was more appropriate from the exergoeconomic point of view in comparison to Jatropha oil and other materials. Finally, by increasing the conversion percentage of the reactor, the value of the exergo-environmental index and the factor of exergy stability increased significantly, which was considered as an advantage from an environmental standpoint.

Kinetic and optimization study of ultrasound-assisted biodiesel production from waste coconut scum oil using porous CoFe2O4@sulfonated graphene oxide magnetic nanocatalysts: CI engine approach

In this study, CoFe2O4@sulfonated graphene oxide (SGO) heterogeneous nanocatalyst was synthesized and utilized to produce biodiesel from waste coconut scum oil (WCSO). The structural features of CoFe2O4@SGO nanocatalyst were evaluated by SEM, TEM, EDX, FTIR, XRD, CO2/TPD, VSM, and BET analyses. According to these analyses, CoFe2O4@SGO nanocatalyst has high specific surface area, suitable functional groups, and good reactivity. The highest biodiesel yield using CoFe2O4@SGO nanocatalyst in optimal conditions (MeOH/WCSO ratio = 12.41, temperature = 64.73 °C, catalyst concentration = 2.24 %, and ultrasonic time = 33.08 min) was 96.87 %. The yield of biodiesel decreased from 96.91 % to 90.17 % after six reuse cycles, which demonstrates the significant stability of CoFe2O4@SGO nanocatalyst in the transesterification process. After 7 reuse steps, XRD and CO2/TPD analyzes revealed that the catalytic activity and crystallinity of the nanocatalyst were almost retained. The kinetic behavior of biodiesel generation showed that the transesterification reaction is endothermic. Enhancing the concentration of biodiesel in the fuel mix had a positive impact on the reduction of CO and UHC emissions, as well as diesel engine parameters such as cylinder pressure, BP, EGT, BSFC, and BTE. Owing to the high biodiesel yield, significant reusability, and positive impacts on the diesel engine, CoFe2O4@SGO nanocatalyst is recommended for industrial applications.

An economic, and environmentally benign Psidium guajava L. leaves catalyst for biodiesel production at room temperature: Process optimization, and life cycle cost analysis

Biodiesel has emerged as a popular alternative to conventional fossil fuel in transportation sector and thus producing low-cost biodiesel is a topic of interest for a large community of researchers. This study reports the preparation of an efficient and robust heterogeneous catalyst from dried Psidium guajava L. (Guava) leaves and its application towards generation of biodiesel from soybean oil at room temperature. The biomass material was calcinated at variable temperature and the efficiency of each of the catalyst prepared was studied. The catalyst generated as well as the product biodiesel was thoroughly characterized using sophisticated analytical techniques. The catalyst was found to have mesoporous structure with active basic sites which contributed towards accelerating the transesterification process. Detailed characterization unveiled the occurrence of Ca as oxide and carbonate, in addition to a certain quantity of K in oxide and carbonate form, which contribute to the catalyst’s activity. Maximum biodiesel yield of 95.8 % was observed for reaction performed under optimum experimental conditions i.e., 1:17 oil-to-methanol ratio, 6 wt% loading of GL-850 (catalyst prepared by calcination at 850°C), and 15 % n-Hexane loading for 3 h at room temperature. GL-850 demonstrated exceptional recyclability for up to the fifth cycle exhibiting a mere 3.7 % decline in yield. The calculated expense for 1 kg catalyst was found to be $0.478, whereas the production cost of 1 kg biodiesel was found to be merely $1.120, indicating a strong economic feasibility of the process.

Comparative Study of Immobilized Biolipasa-R for Second Generation Biodiesel Production from an Acid Oil.

The primary objective of this work is to develop a sustainable biocatalytic transesterification process for low-grade oils, aligning with EU green technology requirements for the shift to second generation biodiesel. Thus, we investigated the immobilization and subsequent application of the lipase Biolipasa-R on transesterification processes to produce fatty acid methyl esters (FAMEs) from both a sunflower oil and an acid oil which is a bioproduct of the biodiesel industry. The lipase was immobilized on biomaterials, such as diatomaceous earth, with a yield of 60 %, and commercial carriers such as methacrylic resins with a yield of 100 %. The enzyme demonstrated superior activity when immobilized on diatomaceous earth, particularly in reactions involving the acid oil, outperforming the benchmark enzyme Novozym® 435 (95.1 % and 35 % conversion respectively). This work highlights the potential of Biolipasa-R as a cost-effective and efficient biocatalyst for biodiesel production and emphasizes the environmental benefits of utilizing industrial byproducts and eco-friendly immobilization techniques. The findings suggest that Biolipasa-R is a promising candidate for industrial applications in biodiesel production, offering a sustainable solution for waste management and energy generation.

A comparative study of first and second generation biodiesel blends under quaternary injection strategies for enhanced engine performance and reduced emissions

Biodiesel is a promising renewable alternative fuel, offering compatibility with conventional engines without necessitating significant engine modifications. To facilitate the practical integration of biodiesel into engine systems, this study evaluates the performance of two different biodiesel blends (fatty acid methyl ester and hydrogenated catalytic) in a turbocharged inter-cooled diesel engine. The research employs quaternary injection techniques an advanced injection technique, which involve multiple injection events per cycle to enhance engine combustion and emission characterictics of the biodiesel blend fuels and comparing their performance and emission characteristics with those of conventional diesel. Results showed that fatty acid methyl ester biodiesel effectively reduced the CO, UHC, and NOx emissions at lower blend ratios (up to 10 %), with minimal impact on the brake-specific fuel consumption. Conversely, hydrogenated catalytic biodiesel demonstrates notable advantages in reducing fuel consumption with carbon monoxide and particle emissions, particularly for higher blend ratios (20 %), leading to improved indicated thermal efficiency. Additionally, an investigation on higher biodiesel blends under varying early injection timings showed that, optimal fuel efficiency was observed at an early injection timing of −43.6 °CA, accompanied by reductions in total particle number and unburned hydrocarbon emissions albeit with elevated carbon monoxide and nitrogen oxide emissions. These findings suggest that advanced injection strategies combined with sustainable biodiesel blends can significantly improve engine performance and reduce environmental impact, supporting the transition towards cleaner and more efficient transportation fuels.

Biodiesel Prepared Through Silver Doped Blended Heterogeneous Catalyst and Soybean Oil

Biodiesel amalgamate with silver doped nickel and calcium blended oxide catalyst & soybean oil. Alkaline earth metal calcium and the use of nickel blended oxide integrated and optimized throughout a blending process that after silver doped in differing percentages to research the outcome of prepared catalysts on the change oil to FAME. Catalytic characteristics such as surface area, energy band difference, crystallinity, morphology, and the composition of prepared samples explored utilizing different BET, FTIR, XRD, SEM, and EDX methods. Silver doped 20 percent NiO-CaO blended oxide catalyst defined with a distinctive weight percentage of silver 2wt percent Ag found to be most viable with 80 percent transformation of oil. The optimized response variable for the change of biodiesel was alcohol to oil proportion 15:1, response temperature 64oC, and catalytic converter stacking 05wt percent. This prepared catalyst has added significance as a blended catalyst for biodiesel generation. Key Words: FAME, Transesterification, Silver, Mixed Oxide, Catalyst

Biodiesel production from spent coffee grounds utilizing pomegranate/orange peel biochar as a green and renewable nanocatalyst: Compression ignition engine performance and emission

In this research, a novel pomegranate/orange peel-derived activated carbon (POPAC) green heterogeneous nanocatalyst was developed for the conversion of spent coffee grounds oil (SCGO) into biodiesel by ultrasonication and its application in diesel engine characteristics. The surface and texture attributes of the POPAC green nanocatalyst were scrutinized employing SEM, EDX, CO2-TPD, XRD, TEM, FTIR, Raman, and BET. Based on the response surface methodology (RSM) outcomes, the highest biodiesel efficiency employing POPAC green nanocatalysts was 95.24 %, which was attained at optimal conditions (i.e., molar proportion of 11.02, nanocatalyst content of 2.56 wt%, ultrasonic time of 30.77 min, and temperature of 60 0C). Moreover, the stability assessment demonstrated the high reusability of POPAC green nanocatalysts, with biodiesel efficiency remaining at 87.43 % even after the 7th round. Further, the kinetic survey exhibited that the biodiesel synthesis is endothermic and the conversion rate is enhanced by boosting the temperature. Besides, the impact of merging biodiesel with the diesel/biodiesel combination at diverse torques was scrutinized on the emission of exhaust output (e.g., UHC, NOx, CO, and CO2) and engine crucial characteristics (i.e., BP, EGT, BTE, and BSFC), and encouraging results were acquired. Briefly, due to special attributes including high catalytic performance, substantial recyclability, and eco-friendliness, POPAC green nanocatalyst are highly suggested for biodiesel generation.

Vigna mungo (L.) Hepper as Heterogeneous Catalyst for Generation of Biodiesel from a Mixture of Multiple Oil Feedstocks

A cost-effective catalyst is essential to reduce the expenses of producing biodiesel. This study is aimed at utilizing the waste of the black gram (Vigna mungo (L.) Hepper) plant as an efficient catalyst for producing biodiesel from a blend of different edible and inedible oils. The catalyst was developed by igniting the dried material and then subjecting it to calcination at 550°C for 2 h. The feedstock was prepared by mixing the oils in an equivalent ratio for the reaction. Various sophisticated techniques such as XRD, FT-IR, XPS, BET, FESEM-EDX, HRTEM, and SAED were employed to characterize the prepared catalyst. The catalyst’s catalytic activity was assessed by transesterification of the oil mixture. The optimized transesterification conditions were 10 wt% of catalyst loading, 9 : 1 of MTOR, 65°C of reaction temperature, and 1.6±0.14 h of reaction time producing 94.79±0.27% of biodiesel yield and 96.86% oil conversion. The calcined catalyst’s alkaline solubility was found to be 2.77 mmol/g, basicity as 0.13 mmol/g, and 14.57 per hour as the turnover frequency (TOF). Catalyst reusability was conducted and found that the catalyst could be reprocessed up to three successive cycles. The synthesized biodiesel’s physicochemical characteristics were assessed and found to conform to ASTM D6751 and EN 14214 requirements.

Investigation of nanoparticle (Fe3O4) addition to 3rd generation biodiesel (spirulina microalgae)/diesel mixture as an innovative fuel according to different engine variables: An RSM optimization

In order to reduce dangerous air pollution and lessen the hazards associated with climate change, biofuels made from vegetable biomass can be utilized as fuel in diesel engines. However, feedstocks and the crop space needed for their cultivation are unavoidable barriers that hinder its adoption and result in a shortage of farmland for increasing food profits. Nevertheless, microalgae are the most reliable and competent biodiesel supply because they are not edible and do not require cropland. Additionally, the addition of nanoparticles has become popular to improve the negative aspects of biodiesel. Based on these, in this study, multi-purpose optimization research was conducted on the addition of iron oxide (Fe3O4) nanoparticles in three different amounts (25, 50, and 75 ppm) to 20 % synthesized spirulina microalgae biodiesel (SSMB)/80 % diesel mixtures. Tests were conducted at three different compression ratios (14.5:1, 15.5:1, and 16.5:1) (CoR) and four different engine loads (25 %, 50 %, 75 %, and 100 %). The response surface methodology (RSM) optimization process was performed with the test results. According to RSM, a desirability coefficient of 0.8299, 15.80:1 CoR, 68 ppm AoN, and 45 % LoE were the ideal conditions. The optimum responses under these circumstances were 421.9653 g/kWh, 19.4014 %, 0.0939 %, 4.0785 %, 73.1716 ppm and 253.0620 ppm for brake-specific fuel consumption (BSFC), brake-thermal efficiency (BTHE), carbon monoxide (CO), carbon dioxide (CO2), hydrocarbon (HC), and nitrogen oxide (NOx), respectively. RSM could be used successfully because the error rates (maximum 6.5 %) when comparing the test results with the RSM optimization outcomes were within reasonable bounds.

Optimizing the model-prediction of date palm fronds-derived producer gas and third generation biodiesel powered dual-fuel engine by employing Bayesian-optimized Boosted Regression Trees for enhanced prognostics

The global issue concerning the dual problem of economic energy shortage as well as greenhouse gas emission needs urgent attention. Due to its abundance and carbon neutrality, waste biomass is a good energy conversion feedstock. This research suggests a unique method for using date palm frond waste biomass-derived producer gas and algal biodiesel as sustainable diesel engine fuels. The Bayesian-optimized neural networks and Bayesian-optimized Boosted Regression Trees were employed to optimize engine combustion and emission performance. This was further enhanced with the application of k-cross fold to prevent the model from overfitting during training. The working of dual-fuel engines is a complex phenomenon owing to the employment of two different types of fuel one is liquid (biodiesel + diesel) while the other one is gaseous (Producer gas). The present endeavor was undertaken to handle this with the application of advanced data learning methods. The engine was tested at different compression ratios, engine loads, and fuel injection pressures for brake thermal efficiency, diesel fuel substitution, and emission. Both the Bayesian-optimized neural networks and Bayesian-optimized Boosted Regression Trees could predict the engine output with good prediction efficiency with comparable performance, however, the Bayesian-optimized Boosted Regression Trees-based models were more robust with a coefficient of determination value in the range of 0.9617–0.9999 and mean squared errors as low as 0.001. The mean absolute percentage error was very low in the range of 0.0316–5.231. The Theil’s U2 values were in the range of 0.0029–0.0126.

Prioritizing the valorization strategies of an invasive fern (Azolla) in a wetland

Wetlands play a vital role as one of the most important natural habitats on our planet. However, the survival of wetlands is threatened by various issues, including the arrival of invasive and non-native aquatic ferns. In this regard, Azolla filiculoides has become a serious problem for the Anzali wetland. The valorization of Azolla can contribute to the establishment of a collection system for this invasive fern, which can consequently reduce the harmful impact of this fern on the wetland, and it can be considered as a free and available source of biomass. Therefore, a fuzzy analytical hierarchy process was applied to rank the valorization strategies of this invasive fern. In the first step, four evaluation criteria (technical, economic, social, and environmental) and six valorization strategies were identified for the analysis through a literature review and expert opinions. The valorization strategies for Azolla were: 1) no collection, 2) collection and landfilling, 3) direct use as livestock and poultry feed, 4) composting, 5) biogas generation, and 6) biodiesel generation. The results revealed that the economic criterion had the highest priority for Azolla valorization, followed by environmental, technical, and social criteria, respectively. Regarding the valorization strategies, biodiesel was identified with the highest priority according to economic and social criteria, and biogas was the strategy with highest priority based on the environmental and technical criteria. In overall, biodiesel, biogas, and composting were ranked as the most appropriate valorization strategies for Azolla in the investigated wetland, respectively. Implementation of the identified valorization strategies can potentially promote the circular economy at the regional level and reduce the adverse effects of the invasive fern on the wetland ecosystem.

A Green Nanocatalyst for Fatty Acid Methyl Ester Conversion from Waste Cooking Oil

This study used a novel combination of cellulose nanocrystals (CNCs) and calcium oxide (CaO) nanocomposite (CaO/CNCs) for the production of biodiesel from waste cooking oil. The filter paper was used as a raw cellulose source to produce the CNCs from the acid hydrolysis of cellulose with sulfuric acid. The as-synthesized CaO/CNC nanocomposite is recyclable and environmentally friendly and was characterized using Fourier transform infrared spectroscopy, energy dispersive X-ray, scanning electron microscopy, and X-ray diffraction. The optimum process parameters investigated are a 20:1 methanol-to-oil molar ratio, 3-weight percent catalyst concentration, 60 °C temperature, and 90 min of reaction time. Under the optimum conditions, a biodiesel yield of 84% was obtained. The CaO/CNC nanocomposite achieved five times reusability, indicating its effectiveness and reusability in the transesterification reaction. The synthesized biodiesel chemical composition was examined using FTIR, GCMS, 1H-NMR, and 13C-NMR, and its properties, including specific gravity, color, flash point, cloud point, pour point, viscosity, sulfur content, sediments, water content, total acid number, cetane number, and corrosion test, were ascertained using ASTM standard practices. The outcomes were determined to fulfill global biodiesel standards (ASTM 951, 6751). Five successive transesterification processes were used to test the regeneration of the catalyst; the first three showed no distinct change, while the fifth cycle showed a reduction of up to 79%. The innovative composite CaO/CNC and used cooking oil are stable, affordable, and extremely successful for long-term biodiesel generation.

Artificial intelligence based-prediction of energy efficiency and tailpipe emissions of soybean methyl ester fuelled CI engine under variable compression ratios

Biodiesel, a widely adopted substitute for conventional mineral diesel, is often derived from raw vegetable oils. The use of non-edible oils for the production of biodiesel has been favored for an extended period of time due to the potential impact on the availability of edible oil as a food source. The generation of soybean methyl ester biodiesel using the transesterification process. The primary objective of this study is to examine the potential use of soybean methyl ester biodiesel (referred to as "S") as a substitute for conventional diesel fuel in a standard light-duty compression ignition four-stroke, single-cylinder, water-cooled engine. The present study aimed to evaluate the impact of increased compression ratio (ranging from 14 to 18) on several combustion, performance, and emissions characteristics. This investigation was conducted using biodiesel blends consisting of 5%, 10%, 20%, and 40% soybean methyl ester, and the results were compared with those obtained using conventional diesel fuel. Additionally, in order to enhance the test results, a training process is being conducted on an artificial intelligence network (ANN). The analysis of the data indicated a positive correlation between the compression ratio (CR) and the in-cylinder pressure values at maximum load conditions. Additionally, a negative relationship was seen between the CR and the brake-specific fuel consumption (BSFC), suggesting a drop in BSFC as the CR rose. Upon evaluating the discharge numbers, it was seen that there was a notable reduction in other pollutants, a fall in NOx emissions, and an elevation in haze levels. Nevertheless, surpassing a sulphur content of 20% has an adverse impact on both emissions and the overall functioning of the engine. Based on the findings of the artificial neural network (ANN), the prediction results demonstrate a commendable capacity to accurately predict the experimental data with the R-value changing from 0.81919 to 0.95028 for all engine performance, combustion, and emission metrics.

Assessment of the Potential of Sunflower Grown in Metal-Contaminated Soils for Production of Biofuels

Environmental biotechnology needs solutions that are associated with a low budget and cleaner remediation, and which are connected to resources and energetic valorization, to be able to encourage a circular bioeconomy. A prospective resolution for heavy-metal-contaminated soils is the application of phytoremediation approaches merged with bioenergy generation using the resulting biomass. Sunflower (Helianthus annuus) has been studied as a feedstock for biodiesel generation, and appears to be very attractive for biogas and bioethanol production. The current study reports an innovative energetic valorization approach of H. annuus biomass derived from the application of a phytoremediation strategy devised to remove Zn and Cd from an industrially contaminated soil (599 mg Zn kg−1 and 1.2 mg Cd kg−1)—and its comparison to the analysis of the same energetic valorization pathway for sunflower plants growing in an agricultural non-contaminated soil. After plant harvesting, bioethanol was produced from the aboveground tissues, and applied in the transesterification of the oil obtained through seed extraction for the generation of biodiesel. Also, biogas production was assessed through the root’s biomass anaerobic digestion. Similar yields of oil extraction—0.32 and 0.28 mL g−1 DW—were obtained when using seeds from H. annuus cultured in contaminated and non-contaminated soils, respectively. The production yield of bioethanol was superior using biomass from the agricultural non-contaminated soil (0.29 mL g−1 DW) when compared to the industrial metal-contaminated soil (0.20 mL g−1 DW). Zinc was measured in minor levels in bioethanol and oil (ca. 1.1 and 1.8 mg mL−1, correspondingly) resulting from the biomass cultivated in the industrialized soil, whereas Cd was not detected. The production yield of biogas was superior when using root biomass from H. annuus cultivated in agricultural non-contaminated soil (VS max. ca. 104 mL g−1) when compared to the one deriving from the industrial contaminated soil (VS max ca. 85 mL g−1). Generally, results demonstrate that substantial production yields of the tested biofuels were attained from biomass resulting from phytoremediation, corroborating this integrated original approach as a valuable alternative for the phytoremediation of HM-polluted soils and as an important strategy for plant biomass valorization.