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• A comprehensive review of hydrogen production techniques. • Performance and emissions parameters are discussed for SI and CI engines. • A review on fuel injection techniques. • Technical challenges for hydrogen-fueled engines. The development of new energy sources to change or lessen the use of conventional nonrenewable energy is also driven by the growing concern over pollution from internal combustion engines. In this situation, it is discovered that using hydrogen in internal combustion engines offer a possible solution to these problems. The unique physical and chemical characteristics of hydrogen for internal combustion engines (ICEs) are called out. There are several hydrogen production techniques are discussed as water electrolysis (solar & wind energy), gasification of biomass, coal gasification, methanol and ammonia decomposition, steam reforming process and photochemical splitting of water. The majority of research found that hydrogen enrichment fuels significantly improved engine performance in terms of thermal efficiency, energy consumption, and fuel consumption. Furthermore, given suitable operating circumstances, both spark-ignition (SI) and compression-ignition (CI) engines can achieve declines in exhaust pollutants such as HC, CO, CO2, NOx, smoke, and soot, and also summarize the utilization of hydrogen in the SI and CI engines aided improvements in engine performance and exhaust emissions under appropriate operating conditions. An assessment of various fuel induction techniques (fuel carburation, port fuel injection and direct injection) and the paybacks of using the synergies of particular solutions is offered, as well as an overview of the use of hydrogen as an internal combustion fuel, covering operations in both SI and CI engines. The objective of this study is to deliver a comprehensive review related to the hydrogen production techniques, the effect on performance and emissions of hydrogen addition as a fuel and injection techniques in a spark ignition and compression ignition engine, and future challenges have been discussed in this article. [ABSTRACT FROM AUTHOR]

[Display omitted] • Molecular interaction types performed by diesel–biodiesel mixture were studied. • Diesel molecule distributions around biodiesel were evaluated in a simulation box. • Diesel's alkane class is most sensitive to increased biodiesel proportion. • The saturation degree of the biodiesel impacts the mixture density. • Results reveal that diesel molecules have higher values of diffusion coefficients. Blends of diesel–biodiesel are a crucial alternative for petrodiesel substitution. However, biodiesel faces challenges such as high density and kinematic viscosity, which can affect the properties and performance of the blends. Based on this, the investigation of the impact of adding biodiesel into diesel fuel at percentages of 12%, 15%, 18%, and 21% using molecular dynamic simulations is presented. The density of the blends was experimentally measured and calculated with good agreement, which indicates a favorable description of the interactions by the OPLS-AA force field. Obtained results suggest that alkanes and isoalkanes showed higher fluctuations and were most sensitive to the variation of the percentage of biodiesel in diesel. The other classes of molecules did not show significant variations in interactions, suggesting that π-π interactions are unaffected by the biodiesel addition. The spatial distribution functions revealed that diesel molecules are organized homogeneously around methyl oleate and methyl linoleate, whereas aliphatic hydrocarbon and aromatic molecules are in distinct regions. The diffusion coefficients (Di) showed that the diesel molecules possess higher values, and the biodiesel addition increases the Di of the blend due to the methyl esters carbon chains, which present lower diffusion than diesel molecules. Finally, physical parameters and simulations revealed that the biodiesel addition into diesel fuel in the proportion up to 21% did not negatively impact the density and viscosity limits established by standards ASTM, EN, and ANP Resolution. [ABSTRACT FROM AUTHOR]

The rapid increase in automobile ownership has brought about an increase in pollutant emissions, the blending of alcohols can effectively reduce conventional pollutant emissions from diesel engines. However, alcohols have poor inter-solubility with diesel fuel. This study investigates the effects of blending different alcohols on the spray and combustion characteristics of diesel, with biodiesel as the cosolvent. The results show that among the three alcohols, blending methanol has the best improvement in the gas-liquid phase spray characteristics, followed by ethanol and propanol. The GL-SCA and GL-SPA of the methanol blends are 8.2 % and 2.3 % larger than those of the ethanol blends, and 19 % and 11.9 % larger than those of the propanol blends, respectively. Among the four fuels, fuel blended with methanol emits the least normalized sum KL, 45 % less than that of diesel, 23.8 % less than that of ethanol blended fuel, and 35.3 % less than that of propanol blended fuel. • Effect of alcohols on spray and combustion of diesel with biodiesel solvent is studied. • Methanol has the best improvement in the gas-liquid phase spray characteristics. • Fuel blended with methanol emits the least soot. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the impact of nickel-incorporating diverse metal oxides (MgO, La 2 O 3 , CeO 2 , SiO 2) supported on alumina on the Diesel steam reforming reaction. Catalytic activity tests were performed within a reaction period of 6 h at 800°C and atmospheric pressure. The amount of catalyst is 30 gr in each experiment corresponding to a LHSV value of 0.2 hr−1. The tests proved that the performances of Ni-containing La 2 O 3 and CeO 2 -supported catalysts were highly stable and active in steam reforming of Diesel, giving complete conversion. The incorporation of CeO 2 (20 % wt) into Al 2 O 3 support resulted in a significant reduction in the amount of coke formation from 0.85 % to 0.26 %. In order to investigate catalyst stability, time-on stream tests extending to 6 days, totaling 36 hours were performed using 5Ni@10La 2 O 3 -Al 2 O 3. As a result of the long-term stability test, no deactivation has been observed under the test conditions despite very few amounts of carbon (1.33 wt%) formed. When comparing the short-term and long-term tests, similar syn-gas production results were observed, along with approximately the same amount of carbon formation. [Display omitted] • Commercial Diesel is used as fuel for H 2 rich gas production via steam reforming. • Systematic comparative study of variety supports are assessed in diesel steam reforming reaction. • 5Ni@10La 2 O 3 -Al 2 O 3 is presented high H 2 content (67 %) with low coke formation (1.33 %) during TOS extending to 6 days. • 5Ni@20CeO 2 -Al 2 O 3 catalyst has the lowest coke formation (0.26 %). [ABSTRACT FROM AUTHOR]

With stringent regulations of internal combustion engine on reducing CO 2 emission, ammonia has been used as an alternative fuel. Investigating how engine-related performance is affected by partial ammonia replacement of diesel fuel is essential for understanding the combustion. Therefore, in this study, a three-dimensional numerical simulation model is developed for the burning of two fuels of diesel and ammonia based on relevant parameters (i.e., compression ratio, load, ammonia energy fraction, etc.) in a lab-made diesel engine. The consequences of load and compression proportion on combustion and pollutant emissions are investigated for ammonia energy fractions between 50% and 90%. When the ammonia portion rises, the increased ammonia equivalent ratio causes ammonia to move away from the dilute combustion boundary and accelerates the combustion rate of ammonia. An increase in compression ratio significantly increases the specified thermal performance and combustion efficacy. When the compression ratio is 16, as the ammonia energy fractions increases, due to the increase in the proportion of ammonia, that is, the proportion of nitrogen atoms increases, more NOx is generated during the combustion process. When the ammonia substitution rate is 90%, as the compression ratio increases, the cylinder pressure and temperature increase. The combustion efficiency of ammonia increases, generating more NOx and NOx emissions can reach 0.66 mg/m3. At a compression ratio of 18, the NOx emissions can reach 1.59 mg/m3. However, under medium and low load conditions, as the ammonia fraction increases, the total energy of fuel decreases, and the combustion efficiency of ammonia decreases, resulting in a decrease in the heat released during combustion and a decrease in NOx emissions. When the ammonia substitution rate is 90% and the load is 25%, NOx emissions reach 0.1 mg/m3. This research provides theoretical suggestions for the profitable and use ammonia fuel in internal combustion engines in a clean manner. • The effects of compression ratio, load, ammonia energy fraction on the combustion and pollutant emissions are investigated. • The combustion efficiency of the fuel is influenced by ammonia equivalent ratio and combustion characteristics of ammonia. • The indicated thermal efficiency is influenced by the ammonia equivalent ratio and the combustion characteristics of ammonia. • This study provides a theoretical guidance for the efficient and clean utilization of ammonia fuel in engines. [ABSTRACT FROM AUTHOR]

The present study successfully synthesized MnWO4@g-C3N4 and CuWO4@g-C3N4 nanocomposites which demonstrated high efficiency and recoverability as a robust catalyst for ODS of model (DBT) and real fuel oil (kerosene and diesel). The manufactured composites were thoroughly characterized using XRD, TGA, FTIR, SEM and EDX confirming its physicochemical properties. The SEM results revealed that MnWO4 and CuWO4 nanoparticles were well organized on the exterior of g-C3N4 forming interesting spherical particle morphology. Under optimized conditions, the nanocomposites MnWO4@g-C3N4 and CuWO4@g-C3N4 exhibited an impressive 98 and 98.5% removal of DBT, respectively from the model fuel (100 mg/L) within 180 min at a temperature of 45 °C using 1 mL of oxidant and 0.1 g of catalyst amount. Furthermore, the catalytic activity of composites was investigated for real fuel desulfurization and promising results were achieved. Moreover, the fuel properties were in accordance with ASTM specifications. The study found that the desulfurization reaction followed the pseudo 1st order kinetic models and the negative ∆G indicated a spontaneous method. The nanocomposites exhibited promising reusability as it could be used up to five times without significantly reducing their ability to desulfurize fuel oil. The study highlights its potential for practical applications in reducing sulfur content in fuel oils contributing to cleaner and environment friendly energy production and utilization.Graphical Abstract: The present study successfully synthesized MnWO4@g-C3N4 and CuWO4@g-C3N4 nanocomposites which demonstrated high efficiency and recoverability as a robust catalyst for ODS of model (DBT) and real fuel oil (kerosene and diesel). The manufactured composites were thoroughly characterized using XRD, TGA, FTIR, SEM and EDX confirming its physicochemical properties. The SEM results revealed that MnWO4 and CuWO4 nanoparticles were well organized on the exterior of g-C3N4 forming interesting spherical particle morphology. Under optimized conditions, the nanocomposites MnWO4@g-C3N4 and CuWO4@g-C3N4 exhibited an impressive 98 and 98.5% removal of DBT, respectively from the model fuel (100 mg/L) within 180 min at a temperature of 45 °C using 1 mL of oxidant and 0.1 g of catalyst amount. Furthermore, the catalytic activity of composites was investigated for real fuel desulfurization and promising results were achieved. Moreover, the fuel properties were in accordance with ASTM specifications. The study found that the desulfurization reaction followed the pseudo 1st order kinetic models and the negative ∆G indicated a spontaneous method. The nanocomposites exhibited promising reusability as it could be used up to five times without significantly reducing their ability to desulfurize fuel oil. The study highlights its potential for practical applications in reducing sulfur content in fuel oils contributing to cleaner and environment friendly energy production and utilization. [ABSTRACT FROM AUTHOR]

Artificial neural networks are used as calibration models in routine analytical determinations that involve spectroscopic data. To ensure that the model will generate reliable predictions for new samples, the applicability domain must be well defined. This article describes a strategy for establishing the limits of the applicability domain when the calibration model is a feed-forward neural network. The applicability domain was defined by two limits: 1) the 0.99 quantile of the squared Mahalanobis distance calculated from the network activations of the training set and 2) the 0.99 quantile of the reconstruction error of the training spectra using either an autoencoder network or a decoder network. A new sample with a squared Mahalanobis distance and/or spectral residuals beyond these limits is said to be outside the applicability domain, and the prediction is questionable. The approach was illustrated by predicting the density of diesel fuel samples from mid-infrared spectra and the fat content in meat from near-infrared spectra. The methodology could correctly detect anomalous spectra in prediction using either the autoencoder or the decoder. • A new method to establish the applicability domain (AD) of a regression network. • One limit of the AD derived from the Mahalanobis distance of network activations. • The other limit of the AD derived from spectral residuals from an autoencoder. • A neural network was used to predict the density of diesel samples using IR spectra. • A neural network was used to predict the fat content of meat using NIR spectra. [ABSTRACT FROM AUTHOR]

Perovskite-based catalysts have been explored as low-cost substitutes for platinum (Pt)- based catalysts for diesel particulate matter (DPM) oxidation. In this work, manganese (Mn)-substituted strontium ferrite (SrFeMnO 3-δ) (SFM) as a catalyst was coated on the honeycomb structure of cordierite support and tested for its catalytic performance for DPM oxidation using a real-world engine. The characteristic diffraction peaks due to the presence of the perovskite structure of SFM were observed for the cordierite-supported SFM. Mn was substituted in the lattice of un-substituted strontium ferrite and no other impurities were formed upon the Mn-substitution. Highly agglomerated SFM particles were formed solely due to the perovskite phase formation temperature (900 °C). The SFM catalyst enhanced catalytic Printex-V oxidation performance compared to its oxidation without the catalyst, where Printex V was used as the model DPM. The SFM catalyst showed high CO 2 selectivity upon the oxidation of DPM. These results infer that the SFM catalyst possesses promise as an alternative to commercially available DOC catalysts based on PGM for DPM oxidation. SFM-coated cordierite support performed much better in terms of particle number, mass and surface area than commercial diesel oxidation catalyst (DOC) or without DOC at no engine load. The performance is substantially higher even at moderate engine loads of up to 40% and comparable at very high engine loads of 100%. Detailed investigations on a real engine exhaust and measurement of crucial parameters like particle number, mass and surface area suggest convincing and relatively rare evidence for its potential as a catalyst for diesel exhaust emission control catalyst. [Display omitted] • Manganese was substituted successfully in the structure of strontium ferrite (SFM). • Perovskite SFM catalyst was coated on the honeycomb structure of cordierite support. • SFM-coated cordierite showed improved diesel particulate matter (DPM) oxidation. • Perovskite SFM catalyst showed higher CO 2 selectivity upon the oxidation of DPM. [ABSTRACT FROM AUTHOR]

This paper presents an improved optimization algorithm for the energy management of a renewable energy solar/wind microgrid with multiple diesel generators applied to off-grid remote communities. The main objective aims to solve the economic emission dispatch problem with a price penalty factor to minimize the energy cost and the emission level. An enhanced metaheuristic optimization algorithm, Lévy arithmetic algorithm, is applied to improve the searchability for optimal solution compared to the conventional arithmetic algorithm. The Lévy arithmetic method is used for the management of the microgrid and compared to other metaheuristic optimization algorithms for the same application. Comparative analysis demonstrates good cost savings using the Lévy arithmetic algorithm, compared to other optimization algorithms such as the arithmetic algorithm, crow search algorithm, hybrid modified grey wolf algorithm, interior search algorithm, cuckoo search algorithm, particle swarm algorithm, colony algorithm, and genetic algorithm. • Proposed an energy management algorithm for the PV/Wind/Diesel Microgrid in off-grid remote communities. • Introduced an enhanced arithmetic optimization approach for addressing economic and emission dispatch. • Evaluated the optimization method's effectiveness and comparative study between the LAA and AOA. • Compared the optimized results of proposed method with other well-known optimization techniques. [ABSTRACT FROM AUTHOR]

Nowadays, a car’s engine oil change interval is an essential factor in reducing wear. The correct choice depends on various factors. This study analyzes the changes in the composition of three different engine oils (0W30, 5W30, and 5W40) during the generally accepted oil change interval (15,000 km) in gasoline and diesel cars during the post-warranty period. Commercially available low-level biofuel blends (B7 and E10) were used to power test vehicles in a field test. Engine oil samples were taken every 3000 km for more detailed analysis and tested in an accredited laboratory. The contaminants in the engine oil were determined using several testing methods: spectrometric analysis, gas chromatography, etc. Studies have shown that all used cars have an increase in the number of iron particles, an increased concentration of silicon, and also an increase in the number of nickel particles above 12,000 km. Tests also showed a sharp drop of molybdenum anti-friction additives 4.5 times and a gradual increase in fuel concentration for the Opel Insignia over 12,000 km, but over 9000 km, a significant increase in the concentration of chromium particles. Based on this research results, it is preferable to choose a maintenance interval of no more than 12,000 km for cars during the post-warranty period. In this way, the intensity of engine wear can be reduced due to the loss of adequate protective properties of the engine oil.

The article is an attempt to perform an ecological assessment of passenger cars with various types of engines in road emission tests. The main research problem and, at the same time, the goal was to develop a method for determining the exhaust emissions from motor vehicles in real traffic conditions based on results obtained in homologation tests. The tests were carried out on vehicles equipped with gasoline, diesel, and hybrid engines, and the obtained results were analyzed. All of the selected vehicles were of the same class—passenger cars, with a similar curb weight, similar maximum engine power, and in the same emission class (Euro 6d). The authors compared the dynamic parameters of vehicle motion in established emission tests: Worldwide harmonized Light vehicles Test Cycles and Real Driving Emissions. Four procedures were used to analyze and compare the operating conditions of the vehicles in the WLTC and RDE tests, differing in how the phases in the tests were divided as well as having a different methodology for determining the road emissions in the tests. The procedures were as follows: WLTC (where the test was divided and the determination of the road emission of exhaust gases was carried out according to the standard WLTP procedure), RDE (the road test was divided into sections and the exhaust emission was determined according to the standard RDE procedure), WLTC1+2 (the test was divided into phases: 1 + 2, 3, and 4; a combination of phases 1 and 2 corresponding to the urban section of the RDE test), WLTCRDE (where drive phases were divided and emissions determined in the same way as in the RDE procedure, which assumes the division of the test into sections based on vehicle speed). The implementation of the research task in the form of an algorithm procedure when comparing the dynamic parameters of the movement in the WLTC and RDE tests is the leading goal presented in this article. The division of the WLTC test into sections (urban, rural, and motorway) according to the RDE procedure and also the calculation of the total emissions in the test according to this procedure resulted in obtaining similar road emission values in the test.

The subject of assessing exhaust emissions in real driving conditions has been relevant for a long time. Its introduction into approval tests focused attention on the comparative possibilities of tests performed on a chassis dynamometer and in road conditions. The article is a continuation of research on the possibilities of estimating emissions in the Real Driving Emission test based on emission data from Worldwide harmonized Light Vehicles Test Cycles. The first part discussed the possibility of comparing dynamic parameters in these tests, and the second part discussed the possibility of estimating road exhaust emissions. The work was done in two stages: the first stage involved the use of distance-specific emissions in individual parts of the WLTC test, and the second stage involved the use of exhaust emission rates as datasets divided into intervals defined by vehicle speed and acceleration. Comparative tests were performed for conventional vehicles (gasoline, diesel) and hybrid vehicles. A chassis dynamometer was used to carry out WLTC tests and PEMS equipment was used for the RDE tests. The exhaust gas components that had to be measured in road tests, namely: carbon monoxide, carbon dioxide, nitrogen oxides, and the number of particulate matter, were analyzed. Based on the data collected, parameters such as road emissions and the exhaust emissions rate were determined for each phase of the dynamometer test as well as the road test. Because of this, it was possible to compare the distance-specific exhaust emissions of each vehicle in the two emission tests. The comparison resulted in establishing that it is possible to estimate distance-specific exhaust emissions of conventional and hybrid vehicles in road test conditions, using only the results obtained in the approval test (for selected test phases). The research concluded that it is possible to estimate selected RDE test parameters based on the results obtained in the WLTC test for the tested vehicles.

The wax deposits of diesel may be formed at low environment temperature during the batch transportation of products pipeline, which will contaminate the subsequent gasoline, resulting in the loss of oil mixing. Therefore, researches on wax deposition of diesel are significant to ensure the economic and efficient operation of products pipelines. Herein, the existing theories on wax deposition were reviewed, and the status of experimental study on wax deposition of diesel was clarified from perspectives of static and dynamic experiments. In addition, the prediction models of wax deposition rate of diesel based on the theories of molecular diffusion and shear dispersion were summarized. Thereby, it is pointed out that strengthening the research on wax deposition mechanism, establishing wax deposition model, and quantitatively characterizing the change rules of quality parameters of the subsequent gasoline with the wax dissolved, are the key direction of research on batch transportation of products pipeline. Besides, by systematically representing the progress of researches on wax deposition of diesel, some reference is provided for the relevant deep researches that may be performed in the future.

Using traditional lean air-fuel mixture aftertreatment technologies to reduce NOx at low exhaust temperatures is limited below 175°C. Recent low engine load NOx emission regulations encouraged researchers to explore the potential of fuel physical properties to enable low-temperature, low-NOx combustion under challenging conditions in which the selective catalytic reduction device might be unable to treat engine-out NOx. Three diesel range fuels were developed to explore how the distillation profile affects and may enable low-load diesel advanced-compression ignition. The least volatile fuel is a conventional, commercially available diesel #2 fuel with a cetane number of 45.3. The second-most volatile fuel is diesel #1 fuel, which can also be found commercially. The last fuel, which is the most volatile, is a new formulation designed to target a final boiling point approximately 50 K below diesel #1 fuel and was termed diesel #0 fuel. A computational fluid dynamics model was developed and validated against experimental data to investigate the underlying effects of each of the developed fuels in the combustion process. Finally, each fuel physical property (e.g., density, viscosity, etc.) was changed independently to assess its effect under the same operating conditions and identify potential directions for fuel formulation that may enable improved NOx emissions and reduce the reliance on aftertreatment systems for NOx control. The results showed that although changes in the fuel distillation curve and other physical properties affect the air-fuel mixtures substantially, changes were not sufficient to result in a large impact to low-load NOx formation. The maximum predicted NOx reduction was 11% uncorrected by combustion phasing. The results suggest that further research efforts should focus on changing the chemical properties of the fuel, like the cetane number, to allow higher EGR dilution and stable combustion.

Diesel engines contribute significantly to deteriorating air quality. Tightening legislation has led to various technological advances, but developments differ between countries. In India, air quality has not improved and fine particle (PM2.5) related premature deaths are predicted to increase. In this study, we characterized the particle emissions of an Indian-manufactured BS IV (Bharat Stage, comparable to Euro emission standards) heavy-duty diesel vehicle and studied the effects of different fuels, fuel blends and lubricating oils. The main aims of the study were to investigate the particle emission dependency on fuel types and fuel blends used in India and to produce useful data for further use (e.g. legislative parties and modeling): emission factors (PN, PM, BC, other chemical compounds), size distributions and volatility of particles. Additionally, the sensitivity of the emissions to the lubricating oil choice was studied. Two lubricating oils, two fossil fuels conforming to BS IV and BS VI emission standards and two biofuel – BS IV fossil fuel blends were tested, one containing Renewable Paraffinic Diesel (RPD) and the other renewable Fatty Acid Methyl Ester (r-FAME). The tests were conducted on a chassis dynamometer (Delhi Bus Driving Cycle, DBDC). Our results show that the emitted particles were in ultrafine particle size range, and both the soot mode particles and smaller nanoparticles were affected by fuels and lubricating oils. The transition from BS IV grade diesel to BSVI was shown to have potential in reducing particle emissions (PN and eBC) of heavy-duty diesel vehicles in India. Blending fossil fuel with biofuel strongly affected particle number emissions, chemical composition, and eBC emissions and the emissions were highly sensitive to biofuel type. Changing the lubricating oil had a comparable magnitude of effect as changing the fuel and the results indicate that in order to reduce particle emissions, a combination of fuel and lubricating oil should be chosen, instead of choosing them separately.

The twin crises of fossil fuel reserves depletion and environmental degradation have motivated industrial and research community to seek alternative and renewable energy sources. Biodiesel has dominated the global scene due to numerous advantages associated with it. In this study, biodiesel was synthesized by transesterifying used cooking oil with three different alcohols: methanol, ethanol and mixed methanol-ethanol. The biodiesel samples produced using methanol, ethanol and mixed methanol-ethanol were denoted as BM, BE and BME, respectively. The properties of the biodiesel samples produced were evaluated in accordance with ASTM standards, and a B20 blend of the three kinds of biodiesel (BM20, BE20 and BME20) was tested in a compression ignition engine to evaluate its performance and emission characteristics. Results from the GC–MS analysis showed that alkyl (methyl or ethyl) ester content in BM, BE and BME samples were 97.72%, 91.83% and 84.65%, respectively, indicating that methanol-based biodiesel satisfied the minimum requirement of EN 14214 standard. In addition, a total of 27.6% methyl and 57.05% ethyl esters were contained in the BME sample, suggesting high ethyl ester conversion during methanolysis-ethanolysis reaction. CO emission values of BM20 blend were lower than those of B0, BE20 and BME20, while the B0 discharged the least NOX amongst the fuels tested. In addition, BM20 discharged the least HC compared to B0 and two other biodiesel blends. Based on this finding, it could be concluded that BM20 exhibited the best performance, combustion and emission characteristics amongst the fuels tested in diesel engine.

Carbon nanotubes functionalized with long‐chain compounds were obtained. Using different characterization techniques, such as thermogravimetric analysis (TGA), infrared spectroscopy (FTIR), x‐ray photoelectron spectroscopy (XPS), Raman spectroscopy, surface area analysis and electron microscopy (EM), it was possible to characterize the carbon nanotubes, verifying the presence of the added aliphatic chains, as well as the formation of the amide bonds, the morphological and structural changes of the material. Those functionalized with oleylamine showed dispersion stability in Colombian commercial diesel for at least 70 days, by visual inspection; using UV‐Vis absorbance and particle size measurement it was determined that in the first hours after the generation of the dispersion there was sedimentation of a portion of the material to reach an equilibrium point in which 75 % of the particles continued in suspension. [ABSTRACT FROM AUTHOR]

The present work is focused on the assessment of the performance and fine particulate matter emissions (PM2.5) of a turbocharged four-cylinder direct injection diesel engine operating under dual-fuel mode with Liquefied Petroleum Gas (LPG). For load levels of 30%, 60% and 100%, measurements were taken, keeping the engine speed constant at 2200, 2500 and 3200 rpm, while the engine knock detonation was detected through a non-invasive internal system. According to experimental measurements, the abnormal knock combustion occurred at full load operation with a maximum LPG energy fraction of ~60%. The brake fuel conversion efficiency increased by 2.6% with an LPG energy fraction of 10%, where a fuel saving of 11.9% was achieved with respect to the diesel-only operation. The reduction of diesel consumption was around 50% with respect to 100% diesel operation at full load operations, where the highest brake fuel conversion efficiency was achieved. The brake fuel conversion efficiency decreased as LPG addition increased for all the engine loads. Regarding emissions, PM2.5 decreased with the addition of LPG. However, HC and CO emissions increased as LPG injection was higher. NOx emissions and exhaust gas temperatures were reduced for operation with higher LPG fractions, except for full load levels at 2200 and 2500 rpm. [ABSTRACT FROM AUTHOR]

In this study, chitosan (CT) and naturally occurring acacia gum (AG) blends were employed as emulsifiers to form a series of emulsions developed from diesel and water. Effects of pH level (3, 5, 10, and 12) and various NaCl salt concentrations (0.25–1%) on the stability, viscosity, and interfacial properties of CT-(1%)/AG-(4%) stabilized Pickering emulsions were evaluated. Bottle test experiment results showed that the stability indexes of the CT/AG emulsions were similar under acidic (3 and 5) and alkaline (10 and 12) pH media. On the other hand, the effects of various NaCl concentrations on the stability of CT-(1%)/AG-(4%) emulsion demonstrated analogous behavior throughout. From all the NaCl concentrations and pH levels examined, viscosities of this emulsion decreased drastically with the increasing shear rate, indicating pseudoplastic fluid with shear thinning characteristics of these emulsions. The viscosity of CT-(1%)/AG-(4%) emulsion increased at a low shear rate and decreased with an increasing shear rate. The presence of NaCl salt and pH change in CT/AG solutions induced a transformation in the interfacial tension (IFT) at the diesel/water interface. Accordingly, the IFT values of diesel/water in the absence of NaCl/CT/AG (without emulsifier and salt) remained fairly constant for a period of 500 s, and its average IFT value was 26.16 mN/m. In the absence of salt, the addition of an emulsifier (CT-(1%)/AG-(4%)) reduced the IFT to 16.69 mN/m. When the salt was added, the IFT values were further reduced to 12.04 mN/m. At low pH, the IFT was higher (17.1 mN/M) compared to the value of the IFT (10.8 mN/M) at high pH. The results obtained will help understand the preparation and performance of such emulsions under different conditions especially relevant to oil field applications. [ABSTRACT FROM AUTHOR]

Tranesterification reaction was carried out on raw shea butter oil (SBO) and palm kernel oil (PKO) to separate the ester from glycerol using ethanol in the presence of potassium hydroxide as catalyst. The properties of biodiesel (ethyl ester) obtained from varying proportions of diesel were experimentally determined and compared with that of conventional diesel. The fatty acid profile of the oil samples was determined using standard methods. Four blends (10%, 20%, 25% and 30%) of SBO and PKO by volume with diesel oil were produced and fuel properties determined include viscosity, relative density, specific gravity, flash, cloud and pour points. Mean values of the six fatty acids (palmitic, stearic, oleic, linoleic) obtained for shea butter and palm kernel oil samples were 5.3%, 1.5%, 13.5%, 15.6% and 8.4%, 2.5%, 15.3%, 2.3%, respectively. The viscosity ranged between 1.52 - 16.6 at 40℃ and 100℃; relative density ranged between 826 - 856 kg m-3, specific gravity ranged between 0.861 - 0.901; flash point ranged between 55℃ - 260℃, cloud and pour point values ranged from 4.85℃ to 6℃ and from -25℃ to -12℃, respectively. The transesterification of the oil samples decreased cloud and pour point of the shea butter and palm kernel oil samples. Based on the findings of this study, blends with 10%, 20% and 25% of PKO and SBO content were found to have acceptable fuel properties for use in internal combustion engine. The adoption of the biodiesel will help to meet the increasing demand for energy in West African countries due to the quality of the oil. [ABSTRACT FROM AUTHOR]

In this paper, several methods of exhaust thermal management for Euro VI diesel engine were studied, and the differences of fuel rail pressure, fuel injection advance angle, intake throttle valve in diesel engine exhaust temperature improvement effect and fuel economy were compared. The effects of diesel engine exhaust thermal management on Selective Catalytic Reduction (SCR) temperature and exhaust Nitrogen Oxides(NOx) were quantitatively analyzed under transient test cycle. The results showed that compared with the fuel rail pressure and fuel injection advance angle, the intake throttle valve had the best exhaust temperature management effect. When the intake throttle valve opening was 80%, the maximum temperature can be increased by 111°C; Under the hot start World Harmonized Transient Cycle (WHTC), the SCR added with exhaust thermal management measures had obvious effect on temperature improvement and NOx conversion. The minimum SCR temperature was increased from 181°C to 196°C, and the tail exhaust NOx was reduced from 0.64 g/kwh to 0.21g/kwh, reducing 67% of NOx emissions. [ABSTRACT FROM AUTHOR]

Biodiesel is a domestically produced, clean-burning, renewable substitute for petroleum diesel. Using biodiesel as a vehicle fuel increases energy security, improves air quality and the environment, and provides safety benefits. . This study extracted, characterized and determined the physicochemical properties of biodiesel produced from Desert date (B. aegyptiaca) seed oil using Soxhlet extraction method with n-hexane as the extraction solvent. The oil obtained was characterized using FTIR and GC-MS analyses and its physicochemical properties determined. The oil obtained was subsequently transesterified using methanol and KOH catalyst. The obtained biodiesel was characterized and its physicochemical properties determined. The result showed that B. aegyptiaca seed oil had density of 0.9 g/cm³, viscosity of 6 cSt at 40 °C and viscosity of 2.5 cSt at 100 °C. The cloud and pour points of the oil was 21 and 9 °C respectively. The oil comprised of eleven fatty acids; predominantly linoleic acid (21.88 %), vaccenic acid (13.90 %) and palmitic acid (10.96 %). The biodiesel had density of 0.88 g/cm³, kinematic viscosity of 4.2 cSt, cloud and pour points of 16 °C and 7 °C respectively. The biodiesel also had free fatty acid (FFA) of 0.79 %, iodine value of 42 mgI2/100g and saponification value of 176. The biodiesel primarily consisted of 9,12-Octadecadienoic acid methyl ester (45.46 %), Hexadecanoic acid methyl ester (20.12 %), Butyl-9,12-Octadecadienoate (12.43 %) and Heptadecanoic acid-16-methyl ester (10.43 %). The properties obtained for the biodiesel were comparable to those of biodiesels reported in literature and thus, shows remarkable potentials to be used as substitute to fossil-based diesel fuel. [ABSTRACT FROM AUTHOR]

In this study, droplet tests were carried out for pure and blended forms of diesel fuel, which is the traditional fuel, and trimethyl borate fuel, which is new generation fuels. In this context, the evolution of fuel droplet diameter, flame structure, and flame temperature over time was observed using a high-speed camera and a thermal camera simultaneously. Measurements were made for the addition of 20%, 40%, 60%, and 80% trimethyl borate fuel to diesel fuel in fuel blends. The curves of the time-dependent change of the dimensionless square of the droplet diameter (D/D 0)2 of the fuel droplets considered in the study, in general, have been determined to comply with the D2-law. Also, as the amount of diesel rose, there were high changes in droplet distortion and high deviations from the hemispherical geometry, and also elongation in the dominant shape droplet shape changed times. While the highest flame temperature was monitored by the thermal camera in the flame formed by the trimethyl borate droplet, as the amount of diesel fuel in the mixture increased, the maximum flame temperature decreased, but the burning time of the droplet was prolonged. On the other hand, the shortest ignition delay was measured for trimethyl borate, while the longest ignition delay time was detected for diesel fuel droplet. In general, it has been observed that the addition of trimethyl borate reduces the ignition delay, shortens the extinction time, and increases the temperature during combustion compared to diesel. • The burning time was prolonged as the amount of diesel in the blend increased. • The highest flame temperature was observed for the trimethyl borate droplet. • As the amount of diesel in the blend raised, the flame temperature decreased. • The shortest ignition delay was measured for trimethyl borate droplet. • As the amount of trimethyl borate raised, droplet deformation was upsurged. [ABSTRACT FROM AUTHOR]

The air quality in a hospital's underground car park is a concern because diesel fumes from cars impact upon vulnerable people attending medical consultations. This research aims to quantify the potential health risk associated with a particular hospital car park. Particulate matter was evaluated in the area with direct reading devices for particle numbers and mass concentrations (CPC 3007, EEPS 3090, Trolex Air XD, Nanozen, and Grimm 1109). Elemental and total carbon concentrations were measured following the NIOSH 5040 method, while volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs) were measured through laboratory analysis and Scanning Electron Microscopy and Energy Dispersive using X-Ray Analysis SEM-EDX microscopy. The nanoparticle levels reached over 80,000 nanoparticles/cm3 (double the German Institut für Arbeitsschutz (IFA) benchmark levels). Diesel particulate matter levels measured as elemental carbon were around 35% of the occupational limit, and from the 49 VOCs analyzed only 13 were detected in quantities below the 0.1% of the occupational limit, while levels of the 13 PAHs analyzed, were below the laboratory limit of quantification. The study concludes that particulate matter in the underground car park can easily exceed nanoparticles benchmark levels and could be harmful, mainly to vulnerable people. It is therefore recommended that they use the outdoor car park or minimize their time in the underground one. [ABSTRACT FROM AUTHOR]

We study the effect of price variations over time and across space on search intensity and search time by consumers in retail markets for diesel in France. The main contribution of the paper is that existing work in industrial organisation in this area has already studied the effect of such variability on the first measure of search but not on the second one. Using novel data from daily consultation measures and price information from a government-run website, we find that price dispersion across space increases search activity and the amount of time allocated to search. Furthermore, while contemporaneous price changes do not appear to influence the number of visits and time per visit to the website, several coefficients on past price changes are positive and statistically different from zero. Our results thus suggest that price dispersion and price variability play a role in inducing search by current and potential customers. [ABSTRACT FROM AUTHOR]

In this analytical investigation, preheated palm oil was used in the direct injection diesel engine with various optimization methods. The main purpose of the optimization was to get better results than the conventional engine. Raw palm oil was heated using the heat exchange process to reduce the density and viscosity. The relationship between the output process and factors response was evaluated in the design of experiment methods. The Taguchi method is an important method for optimization of the output response performance and emission characteristics of a diesel engine. Two important factors—output and input—were calculated. The input factors considered were preheated palm biodiesel blend, torque, injection pressure, compression ratio, and injection timing. The output factors calculated were smoke opacity, carbon monoxide emission, and brake-specific fuel consumption by using the signal-to-noise (S/N) ratio and analysis of variance. Carbon monoxide was most impacted by torque conditions through injection timing and injecting pressure, and opacity of smoke emission. Among them, injection timing had a higher impact. Different biodiesel blends were prepared: B10 (90% diesel + 10% oil), B20 (80% diesel + 20% oil), B30 (70% diesel + 30% oil) and B40 (60% diesel + 40% oil). Silver nanoparticles (50 ppm) were constantly mixed with the various biodiesel blends. The smoke opacity emission for the biodiesel blend B30 + 50 ppm silver nanoparticle showed the lowest S/N ratio and achieved better optimum results compared with the other blends. The blend B30 + 50 ppm silver nanoparticle showed the lowest S/N ratio value of 9.7 compared with the other blends. The smoke opacity, carbon monoxide emission, and brake-specific fuel consumption of all the response optimal factors were found to be 46.77 ppm, 0.32%, and 0.288 kg/kW·h, respectively. [ABSTRACT FROM AUTHOR]

Diesel is frequently encountered in coastal ecosystems due to land run-off from road surfaces. The current study investigates how partially weathered diesel at environmentally relevant concentrations, as may be seen during a run-off event, affect coastal microbial communities. A mesocosm experiment using seawater from the Bedford Basin, Nova Scotia, was followed for 72 h after the addition of partially weathered diesel. Sequencing data suggests partially weathered diesel acts quickly to alter the prokaryotic community, as both opportunistic (Vibrio and Lentibacter) and oil-degrading (Colwellia, Sulfitobacter, and Pseudoalteromonas) bacteria proliferated after 24 h in comparison to the control. In addition, total prokaryotes seemed to recover in abundance after 24 h, where eukaryotes only ceased to decrease slightly at 72 h, likely because of an inability to adapt to the oil-laden conditions, unlike the prokaryotes. Considering there were no highly volatile components (benzene, toluene, ethylbenzene, and xylene) present in the diesel when the communities were exposed, the results indicate that even a relatively small concentration of diesel run-off can cause a drastic change to the microbial community under low energy conditions. Higher energy conditions due to wave action may mitigate the response of the microbial communities by dilution and additional weathering of the diesel. [ABSTRACT FROM AUTHOR]

In this study, polyethylene-pyrolysis was investigated under vacuum to yield cracking-oils as substitutes for petro-diesel. At 430 °C and 670 mmHg, highest yield of 86.68% liquid, 6.46% of residues and 6.86% of gas fractions were obtained. The liquid-fraction composition (180–350 °C) was dominated by paraffinic and olefin, as confirmed by GC–MS. The fuel qualities were analyzed using ASTM standards and then compared to the commercial-diesel. The depolymerized oil characteristics are similar to conventional-fuel except for the density, which was increase by adding an appropriate amount of petro-fuel. This process could significantly serves in managing wastes to produce clean-fuels. [ABSTRACT FROM AUTHOR]

This work describes the use of palm stearin oil as a feed for the catalytic hydrocracking to produce the renewable aviation kerosene and diesel using the hydrocracking catalyst in a continuous flow fixed bed reactor. The efficacy of this method is evaluated using several reaction parameters, including hydrocracking temperature, hydrogen pressure, liquid hourly space velocity (LHSV), hydrogen to feed ratio (H 2 /feed) and time on stream (TOS). Higher temperatures and lower LHSVs are dominant to produce kerosene with maximum selectivity of 55.7%, while lower temperatures and LHSVs favoured the diesel production with maximum of 75.4% selectivity. The isomerization reactions were promoted by higher hydrocracking temperature due to the increase in iso-paraffins. The products consist of paraffins (96.9–99.3%), naphthenes (0.1–1.86%) and aromatics (0.2–1.59%). Aromatization reactions were also taking place in the process which is a considerable benefit of this method as aromatization reactions decrease hydrogen consumption. Moderate hydrogen pressure and H 2 /feed ratio favour the kerosene yield. The reaction mechanistic pathway was also proposed for converting palm stearin to biofuels. Furthermore, product yield, selectivity, heteroatom removal, and double bond saturation were also explored. The stability and activity of the catalyst were studied for 600 h without observable deactivation of the catalyst. [Display omitted] [ABSTRACT FROM AUTHOR]

Non-road sectors, such as agriculture and construction machinery, require high energy densities and flexibility in use, which is why diesel engines are mainly used. The use of climate-neutral fuels, produced from renewable energies, such as Oxymethylene Ether (OME) as a diesel substitute, can significantly reduce CO 2 and pollutant emissions in these sectors. In addition to CO 2 neutrality, OME also offers improved combustion characteristics compared to diesel fuel, eliminating the soot–NO x trade-off and thus enabling new opportunities in engine design and calibration. In this paper, the combustion of pure OME on a close-to-production, single-cylinder non-road diesel engine with a pump–line–nozzle injection system is analyzed. A variation of the center of combustion at constant power output was performed for diesel and OME at different operating points. Two injectors were investigated with OME. A study on ignition delay and a detailed thermodynamic analysis was carried out. In addition, the exhaust emissions CO, NO x , V O C , as well as particulate-matter, -number and -size distributions were measured. With OME, a significantly shorter ignition delay as well as a shortened combustion duration could be observed, despite a longer injection duration. In addition, the maximum injection pressure increases. V O C and CO emissions are reduced. Particulate matter was reduced by more than 99% and particle number (>10 nm) was reduced by multiple orders of magnitude. The median of the particle size distribution shifts from 60 to 85 nm (diesel) into a diameter range of sub 23 nm (OME). A significant reduction of NO x emissions with OME enables new degrees of freedom in engine calibration and an efficiency advantage without hardware adaption. [ABSTRACT FROM AUTHOR]