Search Results (136)

This research analyzes the influence of hydroxy on pure diesel and blends of palm oil and coffee husk biodiesel with percentages of 15% and 20%. The experimental tests were carried out in a stationary diesel engine, where the torque and speed varied from 3–7 Nm and 3000–3600 rpm. Hydroxy was used as a secondary fuel with a volumetric flow injection of 4 and 8 lpm. The injection of hydroxy can reduce the BSFC and increase the BTE of the engine when running on pure diesel and biodiesel blends. The results show a maximum decrease of 11.66%, 11.28%, and 10.94% in BSFC when hydroxy is injected into D100, D85P10C5, and D80P10C10 fuels. In the case of BTE, maximum increases of 13.37%, 12.84%, and 12.34% were obtained for the above fuels. The fuels D100 + 8 lpm, D85P10C5 + 8 lpm, and D80P10C10 + 8 lpm achieved maximum energy efficiencies of 28.16%, 27.58%, and 27.32%, respectively. In the case of exergy efficiency, maximum values of 26.39%, 25.83%, and 25.58% were obtained. The environmental and social costs of CO, CO₂, and HC emissions are significantly reduced with the addition of hydroxy in pure diesel and biodiesel blends from palm oil and coffee husk. The injection of a volumetric flow rate of 8 l/min results in reductions of 11.66%, 10.61%, and 10.94% in operational cost when the engine is fueled with D100, D85P10C5, and D80P10C10, respectively, complying with standards essential for safe engine operation. In general, the research conducted indicates that hydroxy injection is a viable alternative for reducing fuel consumption and improving engine efficiency when using biodiesel blends made from palm oil and coffee husk. Full article

The environmental impact of first-generation biodiesel production, particularly deforestation and soil degradation caused by palm and soybean cultivation, has raised concerns about sustainability. In contrast, second-generation biodiesel utilizes waste as feedstock, offering a more sustainable alternative. Used cooking oil (UCO), a significant waste stream, represents a viable feedstock for biodiesel production, reducing pollution and mitigating economic, environmental, and social challenges. While Europe has demonstrated successful UCO waste management strategies, many regions lack efficient systems, leading to improper disposal that causes water eutrophication, soil degradation, and increased wastewater treatment costs. This study develops a comprehensive strategy for UCO management to optimize its energy potential in biodiesel production, using Barranquilla, Colombia, as a case study. Transesterification, identified as the most efficient conversion method, achieves conversion rates of up to 90%. A pilot project in the Barranquilla area estimates that 963,070.95 kg of UCO is generated annually, with the potential to produce 902,108.56 kg of biodiesel. These findings contribute to the advancement of circular economy principles, offering an adaptable framework for sustainable biofuel production in other regions. Full article

The increasing demand for fossil fuels has led the oil industry to explore biodiesel as a renewable alternative, which is crucial for advancing planetary health. Biodiesel offers environmental benefits and shares similar properties with petroleum diesel, making it a promising substitute. However, Palm Oil Mill Effluent (POME), containing sludge palm oil (SPO), presents challenges due to its high free fatty acid (FFA) content. This study proposes novel optimization strategies to reduce FFAs in SPO and improve biodiesel yield. A combination of base neutralization, esterification, and transesterification processes was employed. Neutralization with sodium hydroxide (NaOH) at concentrations ranging from 0.1% to 0.5% w/w was followed by esterification using sulfuric acid (H₂SO₄) with varying methanol-to-oil ratios. The optimal FFA reduction of 2.26% was achieved at a 6:1 methanol ratio. Transesterification with a 7:1 methanol-to-oil ratio yielded the highest biodiesel output of 71.25%. The biodiesel met ASTM standards, with a calorific value of 40.01 MJ/kg, a flash point of 180.5 °C, and a density of 0.86 g/cm³. Economic analysis estimates an annual net profit of USD 244,901,600, demonstrating that this approach provides a financially viable solution while advancing planetary health by reducing dependency on fossil fuels, mitigating climate change, and supporting sustainable fuel production. Full article

This study investigates the synthesis of biodiesel from three vegetable oils with significantly different chemical compositions. Based on the properties of these biodiesel samples, a method was proposed to estimate the density of petrodiesel–biodiesel blends using an artificial neural network (ANN). The ANN employed in this research consisted of 10 neurons. The experimental data showed a high correlation, indicating effective training and precise estimations in relation to the provided training data. The accuracy of the estimations was evaluated by comparing the blending densities determined through the method presented in this study with the mean of three estimations generated by the neural network. The deviation between the determined and estimated values ranged from 4.1 to 25.2 kg/m³, which is attributable to the limited size of the training database. Most errors fell between −7.1% and 3.8%, with the lowest error being observed for petrodiesel–Brassica carinata biodiesel blends. Excellent correlations for both training and validation data were obtained (R = 0.99 and R = 0.98) for blends incorporating palm and Brassica carinata biodiesel. The estimation method using neural networks proposed in this paper can be effectively adapted for other mixtures and to estimate additional blending properties, accommodating each user’s needs. Full article

Overcoming the oxidation stability of biodiesel has been a significant challenge, especially after an extended storage period. To test a major factor affecting biodiesel quality, eight different conditions consisting of water at a concentration of 500 ppm and tert-butylhydroquinone (TBHQ) concentrations of 500, 1000, and 2000 ppm, in combination, were added to palm biodiesel, with no-water-added treatment as the control. Samples were kept in dark storage and air-limited at room temperature for 52 weeks with an initial carbon residue of 0.05 wt%. Every sample was periodically taken for property examination, which included the percentage of fatty acid methyl ester (FAME), iodine value (IV), kinematic viscosity (KV), acid value (AV), and oxidation stability. The properties of the samples with 500 ppm of water-added biodiesel exhibited the most significant degradation, even though oxidation stability (starting from 43.37 h) remained higher than 10.00 h after 32 weeks. The IV dropped 48.43% from 49.92 to 25.56 g I₂/100 g. The KV increased 6.14% from 4.56 to 4.84 cSt. The AV rose from 0.45 to 1.09 mg KOH/g. Biodiesel with 2000 ppm TBHQ added was stable for 22 weeks, with all properties under standard values. However, biodiesel in the same condition but with water contamination, its stability was reduced to 16 weeks. Full article

Lipases are essential in many industrial processes. Although microbial lipases are widely used, plant lipases remain more accessible and abundant, particularly in germinated kernels. This study aims to evaluate the catalytic potential of lipase extract powder of germinated rubber kernels in transesterification reaction. Germinated rubber kernels, lipase extract powder of germinated rubber kernels, and crude oils of palm (PKO), Jatropha curcas (JCO), and rubber (RSO) were characterized. The presence of lipase in the plant extract powder was evidenced by FT-IR and SEM-EDX analyses and hydrolysis reaction. Biodiesel was produced from crude rubber oil. The results showed that germinated rubber kernels have high moisture (33.48%), protein (15.75%), and fat (50.11%) contents. The optimum hydrolytic activities of lipase on PKO, JCO, and RSO were 25.67 U/mL, 26.67 U/mL, and 31 U/mL, respectively, at pH 5. Lipase extract concentration, temperature, and storage time influenced the lipase hydrolytic activity. The optimum biodiesel yield (29.63%) was obtained at 30 °C. The addition of co-solvents (water and n-hexane) to the reaction mixture increased yields from 20.47% (without co-solvent) to 31.06% and 21.85%, respectively. These insights show that germinated rubber seeds are rich in oil and contain lipase with good hydrolytic and catalytic activity. Full article

The use of a high concentration of biodiesel blends has been implemented nationally in Indonesia as part of the government’s program to increase energy security and improve environmental quality. However, a high concentration of biodiesel, specifically a blending volume of 30% (B30), leads to a shorter fuel filter lifetime compared with pure diesel fuel (B0), due to the precipitation of impurities from biodiesel and the presence of contaminants from the environment. A study was conducted involving a rig test to evaluate the effect of using B30 on filter lifetime, referred to as JIS D1617:1998. The results showed that the temperature and cleanliness of the biodiesel had a strong influence on filter blocking. B30 with an ISO cleanliness of 22/21/17 without added standard dust contaminants at 15 °C for 48 h produced larger amounts of deposits compared to B0 with an ISO cleanliness of 16/13/7 with the addition of 1 g of contaminant for the same treatment. B30 with 1 g of additional contaminants soaked at 15 °C produced a larger amount of deposit than B30 with 2 g of added contaminant soaked at ~27 °C. The weighing of the used filters showed that deposits that originated from biodiesel impurities and precipitations were the dominant material causing a reduced fuel filter lifetime. In addition to the cleanliness factor, a decrease in the micron rating of the filter resulted in a shorter filter lifetime. Full article

Large-scale industrial burners are essential components in various industries including power generation and chemical processing. Enhancing their energy efficiency and reducing emissions, particularly nitrogen oxides (NOx), requires a combination of experimental research and computational fluid dynamics (CFD) simulations. While there exist numerous emission control techniques, the main focus of the present review study was the passive control technique. The result of this review indicates that biodiesel fuel crude palm oil (CPO) was found to reduce emission components, particularly carbon components and particulate matter (PM). Moreover, it also mitigates cavitation within the injector’s orifice, reducing wear and tear. Although cavitation enhances spray atomization and creates finer droplets for improved combustion, it can damage injector orifices. Optimizing the orifice design, such as by adopting conical orifices over cylindrical ones, can significantly reduce cavitation and its adverse effects. Furthermore, innovations such as swirling fuel–air premixing within injectors enhance combustion efficiency and lower emissions by improving fuel–air mixing. However, spray characteristics, particularly the Sauter mean diameter (SMD), remain critical for predicting combustion performance. Further investigations into spray fineness and its impact on combustion dynamics are essential for advancing emission control and performance optimization. Full article

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%. Full article

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. Full article

Biodiesel, an eco-friendly alternative to conventional fossil fuels, offers reduced emissions like carbon dioxide, sulfur oxides, and soot. This study explores biodiesel production from a blend of waste oils using a novel biomass-based catalyst derived from the bottom ash of a biomass boiler. Catalyst synthesis involved wet impregnation, a unique approach using previously unreported bottom ash. Characterization via SEM-EDS, BET, FTIR, and XRD revealed its composition and structure. Optimization of biodiesel production involved assessing alcohol molar ratio, catalyst concentration, and reaction time, achieving a maximum FAME concentration of 95% under specific conditions. Blending residual palm oil with waste frying oil enhanced biodiesel properties, demonstrating a maximum FAME concentration at specific catalyst concentration (8%), molar ratio (1:10), and reaction time (2 h). Catalyst reusability, up to three cycles without significant yield variation, showcased its sustainability. The catalyst, primarily composed of calcium, a characteristic biomass bottom ash component, exhibited mesoporous features. Impregnation with eggshells not only altered composition but also ensured a uniform particle size distribution. FTIR and XRD analyses indicated calcium in hydroxide and crystallized forms. Effective catalyst separation methods included decanting or water washing, with optimal biodiesel purity achieved through 3% phosphoric acid washing at 60 °C. Various recovery methods were assessed, highlighting hexane washing as the most efficient, enabling up to three catalyst reuse cycles without substantial efficiency loss. Full article

Biodiesel, an environmentally degradable and renewable biofuel derived from organic matter, has exhibited its capacity as a viable and sustainable substitute for traditional diesel fuel. Numerous comprehensive investigations have been conducted to assess the effects of biodiesel on internal combustion engines (ICEs), with particular emphasis on diesel engine performance metrics, combustion dynamics, and emission profiles. Biodiesel demonstrates a significant decrease in emissions of particulate matter (PM), hydrocarbon (HC), and carbon monoxide (CO) in diesel engines. The addition of biodiesel has shown a minor decrease in power output and a slight increase in fuel consumption and nitrogen oxide (NOx) emissions. Nevertheless, the extensive implementation of biodiesel, despite its potential to effectively reduce detrimental emissions, has encountered obstacles stemming from external influences including restricted availability of feedstock, volatile petroleum oil prices, and inadequate governmental backing. This review presents a concise summary of significant advancements in the global adoption of biodiesel from a sustainability perspective. This review provides valuable insights into the challenges and opportunities associated with the advancement of sustainable biofuel technologies by synthesizing the current state of palm biodiesel and examining global trends in biodiesel implementation. The wider adoption of biodiesel can be facilitated by addressing concerns pertaining to feedstock availability, price stability, and policy support. This would allow for the realization of significant environmental advantages and contribute to a more environmentally friendly and sustainable biofuel. Full article

Biodiesel manufacturing frequently employs sustainable materials like soybeans, microorganisms, palm extract, jatropha plant, and recycled frying oils. The expansion of biodiesel manufacturing has escalated the volume of waste byproducts, encompassing glycerin and non-glycerin organic matter (MONG), jointly known as raw glycerin. MONG is characterized by a low calorific value, a high autoignition temperature, and significant viscosity at room temperature. As a waste product, it negatively affects the natural environment due to the lack of viable disposal methods. Hence, there is a need for its conversion into high-calorific gaseous fuel with significantly less environmental impact. One of the methods for converting MONG into gaseous fuel is the pyrolysis process. This study describes the pyrolytic conversion of MONG conducted on a test stand consisting of a rotating chamber with a shell filled with liquid lead as a heating medium. Based on the measurements and balance calculations, the amount of heat required to preserve the autothermal process was determined. The calorific value and composition of the pyrolytic gas were measured, revealing that 70% of the gas involves compounds characterized by a high calorific value. As a result, the calorific value of dry, purified gas equals 35.07 MJ/kg. A life cycle assessment has been conducted, in order to determine if the produced gaseous fuel matches sustainable development criteria. MONG-based gas is a sustainable replacement of, e.g., natural gas, lignite, or hard coal; however, it allows us to avoid 233–416 kg/h CO₂ emissions per 1 MW_t of heat. Full article

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

The study investigated the use of CeO₂ extracted from monazite with calcium oxide (CaO) as a solid catalyst for biodiesel production. The wet impregnation method was used to produce CaO@CeO₂ mixed-oxide catalysts with 0–50 wt.% CaO. X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area analysis, thermogravimetric analysis (TGA), and a Fourier transform infrared spectrometer (FTIR) was used to characterize the catalysts. In order to determine the optimal preparation conditions, the effect of different CaO compositions on the performance of CaO@CeO₂ mixed-oxide catalysts was examined. The catalytic activity of the CaO@CeO₂ catalyst for the transesterification reaction of palm oil to produce biodiesel was studied. The results show that the optimum yield of biodiesel can reach 97% fatty acid methyl ester over the 30CaO@CeO₂ catalyst at the reaction conditions of 5 wt.% catalysts, methanol-to-oil molar ratio of 9:1, with a reaction temperature of 65 °C within 30 min. The results show that the high catalytic activity and stability of the CaO@CeO₂ catalyst make it a promising candidate for industrial-scale biodiesel production. Further study is needed to improve the stability and efficiency of catalysts in transesterification reactions to achieve a high FAME yield using long-life-span catalysts. Moreover, it is necessary to investigate the economic feasibility of this process for application in large-scale biodiesel production. Full article