Low Sulfur Diesel Research Articles

Effects of the Degree of Unsaturation of Fatty Acid Esters on Engine Performance and Emission Characteristics

Biodiesel is considered an environmentally friendly alternative to petro-derived diesel. The cetane number indicates the degree of difficulty in the compression-ignition of liquid fuel-powered engines. The allylic position equivalent (APE), which represents the unsaturated degree of fatty acid esters, was one of the key parameters for the cetane number of biodiesel. Due to the significant attributes of APE for biodiesel properties, the impact of APE on engine performance and emission characteristics was investigated in this study. The engine characteristics could be improved by adjusting the biodiesel fuel structure accordingly. A four-stroke and four-cylinder diesel engine accompanied by an engine dynamometer and a gas analyzer were used to derive the optimum blending ratio of the two biodiesels from soybean oil and waste cooking oil. Three fuel samples composed of various proportions of those two biodiesels and ultra-low sulfur diesel (ULSD) were prepared. The amounts of saturated fatty acids and mono-unsaturated fatty acids of the biodiesel made from waste cooking oil were significantly higher than those of the soybean-oil biodiesel by 9.92 wt. % and 28.54 wt. %, respectively. This caused a higher APE of the soybean-oil biodiesel than that of the biodiesel from waste cooking oil. The APE II biodiesel appeared to have the highest APE value (80.68) among those fuel samples. When the engine speed was increased to 1600 rpm, in comparison with the ULSD sample, the APE II biodiesel sample was observed to have lower CO and O2 emissions and engine thermal efficiency by 15.66%, 0.6%, and 9.3%, while having higher CO2 and NOx emissions, exhaust gas temperature, and brake-specific fuel consumption (BSFC) by 2.56%, 13.8%, 8.9 °C, and 16.67%, respectively. Hence, the engine performance and emission characteristics could be enhanced by adequately adjusting the degree of unsaturation of fatty acid esters represented by the APE of biodiesel.

Biodiesel derived from waste cooking oil in blends with ultra-low sulphur diesel and its spray macroscopic properties under split injection strategy

There is a significant interest to evaluate alternative injection strategies in order to improve the performance of biofuels and its blends in internal combustion engines as a way to decarbonize the transport sector, particularly in high potence demand niche. Biodiesel is the renewable analogue for petroleum diesel but the performance assessment of its blends from related to their spray macroscopical properties is scarce in the literature. This article evaluates the effect of Waste Cooking Oil Biodiesel (WCO) produced at semi-industrial scale in blends (B05, B10, B20) with commercial Ultra Low Sulphur Diesel (ULSD) on the fuel spray macroscopic properties such as penetration, angle, and area when a split injection strategy is used in a constant volume chamber under non-reactive and evaporative conditions using an injection and back pressure of 120 MPa and 5 MPa, respectively. These results were analysed in conjunction with relevant physicochemical properties of the fuels to identify the optimum diesel-WCO biodiesel blend, that could be implemented in a conventional diesel engine. It was observed that the increase of density and viscosity directly influences spray tip penetration, whereas surface tension affects spray angle. The values of spray penetration and spray area of all fuels during the second injection were higher than those of the first injection. Accordingly, the first injection event provokes an improvement mixing process of the second injection event in all cases. The values of spray penetration and area corresponding to B10 and B20 were higher than those of B5 and ULSD in both injection events at all times. Therefore, the split injection could be an effective strategy to improve the mixing process of biodiesel blends as well as the efficiency and emission performance in conventional diesel engines.

Biodiesel feedstock determines exhaust toxicity in 20% biodiesel: 80% mineral diesel blends

To address climate change concerns, and reduce the carbon footprint caused by fossil fuel use, it is likely that blend ratios of renewable biodiesel with commercial mineral diesel fuel will steadily increase, resulting in biodiesel use becoming more widespread. Exhaust toxicity of unblended biodiesels changes depending on feedstock type, however the effect of feedstock on blended fuels is less well known. The aim of this study was to assess the impact of biodiesel feedstock on exhaust toxicity of 20% blended biodiesel fuels (B20). Primary human airway epithelial cells were exposed to exhaust diluted 1/15 with air from an engine running on conventional ultra-low sulfur diesel (ULSD) or 20% blends of soy, canola, waste cooking oil (WCO), tallow, palm or cottonseed biodiesel in diesel. Physico-chemical exhaust properties were compared between fuels and the post-exposure effect of exhaust on cellular viability and media release was assessed 24 h later. Exhaust properties changed significantly between all fuels with cottonseed B20 being the most different to both ULSD and its respective unblended biodiesel. Exposure to palm B20 resulted in significantly decreased cellular viability (96.3 ± 1.7%; p < 0.01) whereas exposure to soy B20 generated the greatest number of changes in mediator release (including IL-6, IL-8 and TNF-α, p < 0.05) when compared to air exposed controls, with palm B20 and tallow B20 closely following. In contrast, canola B20 and WCO B20 were the least toxic with only mediators G-CSF and TNF-α being significantly increased. Therefore, exposure to palm B20, soy B20 and tallow B20 were found to be the most toxic and exposure to canola B20 and WCO B20 the least. The top three most toxic and the bottom three least toxic B20 fuels are consistent with their unblended counterparts, suggesting that feedstock type greatly impacts exhaust toxicity, even when biodiesel only comprises 20% of the fuel.

Implications of the Use of Biodiesel on the Longevity and Operation of Particle Filters

While biodiesel is one of many necessary steps forward in a cleaner transportation future, alkali metal residuals, including Na and K (in the form of oxides, sulfates, hydroxides, and carbonates) originating from fuel production catalysts were found to be detrimental to emissions control components. Na + K and Ca + Mg (also biodiesel production byproducts) are regulated by ASTM-D6751 standards (American Society for Testing and Materials) to be less than 5 ppm for B100; however, the literature gives examples of physical and chemical degradation of automotive emissions catalysts and their substrates with these Na and K residuals. The purpose of this study is to investigate the impacts of ash from Na-doped biodiesel fuel (B20) on a diesel particulate filter (DPF). Investigations found that the Na-ash accumulated in the DPF has several unique properties which help to fundamentally explain some of the interactions and impacts of biodiesel on the particle filter. The biodiesel-related Na-ash was found to (1) have a significantly lower melting temperature than typical ash from inorganic lubricant additives and Ultra Low Sulfur Diesel (ULSD) fuel resulting in ash particles sintered to the DPF catalyst/substrate, (2) have a primary particle size which is about an order of magnitude larger than typical ash, (3) produce a larger amount of ash resulting in significantly thick wall ash layers and (4) penetrate the DPF substrate about 3× deeper than typical ULSD and lubricant-related ash. This study utilizes numerous characterization techniques to investigate the interactions between biodiesel-related ash and a DPF, ranging from visualization to composition to thermal analysis methods. The findings suggest the need for tighter control of the thermal environment in the DPF when using biodiesel, additional/improved DPF cleaning efforts, and avoidance of unregulated biodiesel with high Na/K levels.

The impact of alternative fuel vehicles on health: a systematic review

Background and Aim: Despite the increasing adoption of alternative fuel vehicles such as electric, hybrid, and clean diesel cars, trucks and buses, the health impacts of these vehicles (e.g., through changes in air quality) is largely unexplored. We reviewed the published literature to assess the state of the evidence on use of alternative fuel vehicles and health. Methods: We conducted a systematic literature search of MEDLINE, Embase, Global Health, CINAHL, Scopus, and Environmental Science Collection databases for articles published January 1990 to November 2021. We included articles presenting observed or modeled data on the association between alternative fuel vehicles and health-related outcomes. We abstracted data, categorized studies based on the type of alternative fuel and health outcomes studied, and summarized the results. Results: In our preliminary findings, 23 of 631 screened articles met our inclusion criteria. The most common vehicle types examined were electric or hybrid electric (n=18, 78%), clean diesel (n=5, 22%), and compressed natural gas (n=3, 13%). Overall, 17 articles (74%) assessed death as an outcome and 8 articles (35%) monetized health benefits. Only one study collected longitudinal data to assess the health impact on a population; the other articles all modeled data. All 23 articles observed some evidence of a positive health impact of adopting alternative fuel vehicles, although magnitudes varied. There was a paucity of information on the environmental justice implications of vehicle transitions (e.g., changing of the spatial distribution of air pollution, emphasis on adoption equity). Conclusions: There is limited information, particularly real-world studies, on the health impact of adoption of alternative fuel vehicles. The current rapid transitioning of vehicle fleets to alternative fuels provides a unique opportunity to conduct natural experiments to quantify health impacts and assess environmental justice implications of alternative fuel adoptions. Keywords: alternative fuels, traffic, review

Ultrasound assisted oxidative desulfurization: A comprehensive optimization analysis using untreated diesel oil

In this research, a process system optimization in the ultrasound assisted oxidative desulfurization (UAOD) with the NaPW/H2O2 system was investigated to determine its sustainability to produce clean diesel. The UAOD process was used to identify the effect of sulfur conversion with ultrasound time (6 to 30 min), amplitude (20 to 60%), catalyst dosage (10 to 500 mg), and temperature (30 to 70 °C). Results showed that the variables of amplitude, catalyst dosage, and temperature were extremely significant (p-value < 0.0001). Strong statistical significance (p-value < 0.0001 and F-value = 24.8) has been displayed for the generated model. The optimum sulfur conversion of 99.6% (theoretical) and 95.0% (verified) in diesel was attained at 27.1 min, 39.9% amplitude, 320.9 mg catalyst, and 69.7 °C. Thus, the results of this study indicated the novel applicability of the UAOD as a desulfurization technology in industrial practice.

Combustion characteristics of microalgae-based dioctyl phthalate biofuel during ambient, preheated and hot engine operation

Presented in this article is a comprehensive analysis of combustion behaviour using Di-octyl Phthalate (DOP) – an oxygenated third-generation biofuel, blended with ultra-low sulphur diesel (D100) in proportions of 10 % (DOP10D90) and 20 % (DOP20D80) (%v/v). The experiments were conducted on a heavy-duty diesel engine during ambient, preheated and hot engine operation. A cold-engine custom-designed drive cycle, with frequent engine stop/start was used. D100 was found to warm up faster by 7 % during the first 120 s of ambient operation, compared to DOP blended fuels. The maximum rate of pressure rise was 18 % and 14 % higher using DOP10D90 and DOP20D80, respectively, compared to D100. Peak apparent heat release rates (AHRR) were 11 % and 7 % higher using DOP10D90 and DOP20D80 fuels, respectively, compared to D100 during the first 120 s of ambient operation. Oxygen bound to the fuel molecule caused an increase in the maximum rate of pressure rise and an increase in the peak AHRR during ambient operation. As the DOP quantity increased in the fuel blend, the ignition delay increased, while the combustion duration decreased. Neither of these parameters was affected by engine warm-up. The shortest combustion duration was observed using DOP20D80, leading to a faster burn rate during the premixed combustion stage during ambient start, compared to DOP10D90 and D100.

Efficient Lubricity Improvers Derived from Methyl Oleate for Ultra Low Sulphur Diesel (ULSD)

Efficient Lubricity Improvers Derived from Methyl Oleate for Ultra Low Sulphur Diesel (ULSD)

Construction of 3D TiO2 nanoflower for deep catalytic oxidative desulfurization in diesel: Role of oxygen vacancy and Ti3+

To prevent SOx emission and produce low-sulfur diesel oil, we develop a 3D assembly TiO2 nanoflower catalyst with controllable oxygen vacancies for oxidative desulfurization (ODS) in diesel oil. The roles of oxygen vacancy (OV) and associated Ti3+ in TiO2 are fully discussed: the increased OV and Ti3+ are beneficial for the promoted chemical adsorption of peroxy groups, from − 0.5 eV to − 1.26 eV; also facile to the reduction of the energy barriers of O-O and O-H bonds cleavage, respectively by 1.38 eV and 1.24 eV, thus greatly boosting the generation of hydroxyl radicals·OH and superoxide radicals·O2-. Besides, the ODS reaction undergoes two possible pathways, the mechanism and the kinetics are investigated. Above all, the 100% ODS rate can be obtained in only 30 min under optimal conditions, showing a promising perspective of oxygen vacancy engineering for converting hazardous sulfides into high-value chemicals.

Experimental diesel spray characterization of the medium-duty injector with single- and multi-hole nozzle configurations under non-reacting, non-vaporizing conditions

Characteristics of diesel sprays injected through Cummins medium-duty ISB injectors were studied experimentally in an optically accessible constant-volume combustion vessel. The experiments were performed with ultra-low-sulfur diesel (ULSD) under non-reacting and non-vaporizing conditions, including different ambient gas densities (23–65 kg/m3), injection pressures (500–1,500 bar), and injection duration times (0.5–1.5 ms). The ambient temperature of the vessel was maintained at a room temperature of 313 K for all the tests. A systematic comparison was made between single-hole (SH) and multi-hole (MH) injector configurations. A plume-to-plume variation in spray penetration length was observed for various operating conditions. A substantial deviation was observed for a specific hole against the averaged plume, indicating that arbitrary selection of the plume index may result in inaccurate spray characterization of the MH injector. The penetration length of the MH injector was shorter than that of the SH injector under the same operating conditions, indicating that a spray model calibrated on SH injector data may not accurately predict the transient spray behavior of the MH injector in practical engine simulations. A square-root correlation of the spray penetration length was applied for both the SH and MH injectors. The spray penetration length and dispersion angles of the ISB SH injector were also compared with those of the heavy-duty Cummins ISX SH injector. While the ISX SH injector showed a faster penetration than the ISB SH injector, the dispersion angle was similar. The differences in spray penetration between ISB and ISX injectors followed the expected trend based on their nozzle hole diameters.

Long-term trend analysis of criteria pollutants in megacity of Delhi: Failure or success of control policies

The study aimed to analyze the long-term trend of four criteria pollutants (PM2.5 and NO2 during 2006–2019; SO2 and CO during 2000–2019) and the effect of pollution control measures in Delhi. The hourly data of PM2.5 and NO2 was taken from six air quality monitoring stations while SO2 and CO data was retrieved from MERRA reanalysis (Modern-Era Retrospective Analysis for Research and Applications) products. PM2.5 and NO2 datasets from six monitoring stations were divided into three categories based on their years of data collection. At all the categories of sites, both the pollutants showed three distinct trends including a decreasing trend which was common from 2015 to 2019. The annual average trends of SO2 and CO showed two distinct trends including an increasing trend which was common from 2013 to 2019. The study analyzed various control policies, among them Compressed Natural Gases (CNG) implementation in December 2002, is a historic measure which was followed by 13.5% decrease in particulate matter trend and 20% increase in NO2 trend during 2002–2005 while 7% decrease in CO trend during 2003–2005. The introduction of ultralow sulfur diesel and closure of coal based thermal power plants reduced SO2 levels significantly during 2011–2012.

Simple Method for the Conversion of Light Cracked Naphtha into Efficient Lubricity Improvers for Ultra-Low Sulfur Diesel.

Light cracked naphtha (LCN) is one of the olefin streams obtained from oil refinery in the petrochemical fluidized catalytic cracking unit. In this communication, we report a new method for the conversion of LCN into lubricity improvers for ultra-low sulfur diesel (ULSD) through a feasible two-step synthetic procedure. In the first step, olefins of LCN were subjected to the hydroboration reaction using BH3 to get the hydroxy LCN derivative which was then subjected to the esterification reaction with different organic acids to get the final LCN esters (6a–j). The lubricating property of the LCN esters was studied at two blending concentrations (300 and 150 ppm, wt/vol) with ULSD. Interestingly, ester (6a) derived from stearic acid showed the tiniest wear scar diameter in both dosage levels. The mechanism of lubricity action of LCN esters on metallic surfaces was studied by analyzing the worn surfaces using scanning electron microscopy and energy-dispersive X-ray spectroscopy techniques. The studies reveal that the lubricity additives derived from cracked naphtha through a simple chemical reaction strategy are promising precursors in enhancing the lubricity of ULSD.

Clean fleets, different streets: evaluating the effect of New York City’s clean bus program on changes to estimated ambient air pollution

BackgroundMotor vehicles, including public transit buses, are a major source of air pollution in New York City (NYC) and worldwide. To address this problem, governments and transit agencies have implemented policies to introduce cleaner vehicles into transit fleets. Beginning in 2000, the Metropolitan Transit Agency began deploying compressed natural gas, hybrid electric, and low-sulfur diesel buses to reduce urban air pollution.ObjectiveWe hypothesized that bus fleet changes incorporating cleaner vehicles would have detectable effects on air pollution concentrations between 2009 and 2014, as measured by the New York City Community Air Survey (NYCCAS).MethodsDepot- and route-specific information allowed identification of areas with larger or smaller changes in the proportion of distance traveled by clean buses. Data were assembled for 9670 300 m × 300 m grid cell areas with annual concentration estimates for nitrogen oxide (NO), nitrogen dioxide (NO2), and black carbon (BC) from NYCCAS. Spatial error models adjusted for truck route presence and total traffic volume.ResultsWhile concentrations of all three pollutants declined between 2009 and 2014 even in the 39.7% of cells without bus service, the decline in concentrations of NO and NO2 was greater in areas with more bus service and with higher proportional shifts toward clean buses. Conversely, the decline in BC concentration was slower in areas with more bus service and higher proportional clean bus shifts.SignificanceThese results provide evidence that the NYC clean bus program impacted concentrations of air pollution, particularly in reductions of NO2. Further work can investigate the potential impact of these changes on health outcomes in NYC residents.Impact StatementUrban air pollution from diesel-burning buses is an important health exposure. The New York Metropolitan Transit Agency has worked to deploy cleaner buses into their fleet, but the impact of this policy has not been evaluated. Successful reductions in air pollution are critical for public health.

Ultralow Sulfur Diesel and Rapeseed Methyl Ester Fuel Impact on Performance, Emitted Regulated, Unregulated, and Nanoparticle Pollutants.

The operation of engines using rapeseed methyl ester (RME) and ultralow sulfur diesel (ULSD) was tested for the combustion properties, emitted regulated, unregulated exhaust pollutants, and the size of nanoparticles. The combustion analysis showed higher apparent heat release rate and shorter ignition delay period during RME combustion than during ULSD combustion. The ULSD engine has a combustion chamber maximum pressure relatively higher than that of RME. This study showed that the heat release rate of ULSD is always higher than that of RME while more fuel consumption occurred from the combustion of biodiesel in comparison with diesel. When the engine is running on RME, HC and NOx formation increased at high loads up to 15% and 13%, respectively; meanwhile, CO concentrations reduced by 30.9% for the same conditions. Most of the particulate matter (PM) emitted from a diesel engine has a particle size from 5 to 100 nm, while the particle size from ULSD ranged from 5 to 40 nm. Overloading the engine caused a decrease in the sizes of emitted PM for both fuels. The smoke number for RME was less than that for ULSD by 33.9% at high loads. For high engine load, the cumulative concentration number for the nucleation mode decreased, while it increased for the accumulation mode. Furthermore, measurements of formaldehyde, ethane, methane, acetylene, ethylene, propylene, and isocyanic acid emissions showed the presence of these harmful substances at very low concentrations (8 ppm) for both fuels.

Combustion Performance and Emission Characteristics of Marine Engine Burning with Different Biodiesel

Ship emissions are one of the main sources of air pollution in port cities. The prosperous maritime trade has brought great harm to the air quality of port cities while promoting the development of the world economy. During the berthing process, ship auxiliary machines emit a large amount of air pollutants, which have a great impact on air quality and public health. Alternative marine fuels are being studied and used frequently to reduce ship emissions. This research was carried out to investigate the gaseous and particles emission characteristics of a marine diesel engine during the application of experimental biodiesel fuels. To study the influence of mixed fuels on engine performance, measurements were made at different engine loads and speeds. Different diesel fuels were tested using various ratios between biodiesel and BD0 (ultra-low sulfur diesel) of 0%, 10%, 30%, 50%, 70%, 90%, and 100%. The results indicated the use of biodiesel has little influence on the combustion performance but has a certain impact on exhaust emissions. The octane number and laminar flame speed of biodiesel are higher than those of BD0, so the combustion time of the test diesel engine is shortened under the mixed mode of biodiesel. In addition, a high ratio of biodiesel leads to a decrease of the instantaneous peak heat release rate, causing the crank angle to advance. As the biodiesel blending ratio increased, most of the gaseous pollutants decreased, especially for CO, but it led to an increase of particle numbers. The particle size distribution exhibits a unimodal distribution under various conditions, with the peak value appearing at 30–75 nm. The use of biodiesel has no effect on this phenomenon. The peak positions strongly depend on fuel types and engine conditions. The particulate matter (PM) emitted from the test engine included large amounts of organic carbon (OC), which accounted for between 30% and 40% of PM. Whereas the elemental carbon (EC) accounted for between 10% and 20%, the water-soluble ions components accounted for 6–15%. Elemental components, which accounted for 3–8% of PM emissions, mainly consisted of Si, Fe, Sn, Ba, Al, Zn, V, and Ni. Generally, biodiesel could be a reliable alternative fuel to reduce ship auxiliary engine emissions at berth and improve port air quality.

Investigation of the Effects of Using Low Sulfur and Rural Diesel as Diesel Fuel in Tractors on Engine/emissions

Energy is one of the main factors that ensure the formation of production, development, and economic conditions between countries. Although fossil fuels pose some problems in terms of the environment and human health, they still have great use in meeting the energy demand in the world. Although there are many studies on alternative fuels in today's conditions, diesel engines are more preferred by the countries in heavy-duty vehicles (construction machines, tractors, and combine harvesters) operating in all kinds of commercial and land conditions that are used in transportation. Diesel engines are more preferred in developing countries due to their high torque and low fuel consumption. For this reason, efficiency, operating parameters, and reducing the environmental emissions of diesel engines used in our country are important. Since agriculture is one of the most important fields of activity in our country, in this study, the engine's characteristics and the effects on the exhaust emissions of the rural diesel used in the tractor and the low-sulfur diesel fuel were experimentally investigated. The maximum torque (1400rpm) used during the field plow of the tractor, which is available in Çerkezköy Hattat Tractor Factory R&D Center, and the maximum power (2100rpm) under other driving conditions were tested with both diesel fuels. When the results of the experiments were compared, it was seen that higher torque and power were obtained with the use of low sulfur diesel fuel, while harmful exhaust emissions were lower than rural diesel fuel. However, when the engine's fuel consumption is compared, it has been determined that rural diesel is consumed less than low sulfur diesel

Wear and Friction Effects on Engine Materials of N-Butanol in Ultra-Low Sulfure Diesel Mixtures

The lack of the sulfur beneficial lubricity in ultra-low sulfur diesel (ULSD) may lead to premature wear and failure of diesel-fuel systems. Mixing of small percentages of, for instance, biodiesels and other biofuels is typically used to add lubricity in ULSD. N-butanol has been recently proved to mix in or replace diesel without compromising engine combustion performance. But anti-wear properties of mixing N-Butanol in ULSD have not previously been studied. This paper presents a tribology study on the effects of N-Butanol in ULSD in a steel-on steel sliding contact. The research work employed a pin on disk tribometer for friction-force data acquisition, and wear was measured by specimen weight-change. The wear results and the friction force evolution observed in tests indicate that the dilutions of ULSD with N-Butanol can lead to a reduction of wear and that there is an optimum rate of dilution, of around 25% of N-Butanol in ULSD, that minimizes wear and increases the mixture lubricity as compared to those of both pure ULSD and pure N-Butanol.

Biological toxicity risk assessment of two potential neutral carbon diesel fuel substitutes

We investigated the biological response of soluble organic fraction (SOF) and water-soluble fraction (WSF) extracted from particulate matter (PM) emitted by an automotive diesel engine operating in a representative urban driving condition. The engine was fueled with ultra-low sulfur diesel (ULSD), and its binary blends by volume with 13% of butanol (Bu13), and with hydrotreated vegetable oil (HVO) at 13% (HVO13) and 20% (HVO20). Cytotoxicity, genotoxicity, oxidative DNA damage and ecotoxicity tests were carried out, and 16 polycyclic aromatic hydrocarbons (PAH) expressed as tbenzo(a)pyrene total toxicity equivalent (BaP-TEQ) were also analyzed. The Hepatocarcinoma epithelial cell line (HepG2) was exposed to SOF for 24 h and analyzed using comet assay, with the inclusion of formamidopyrimidine DNA glycosylase (FPG) and endonuclease III (Endo III) to recognize oxidized DNA bases. The WSF was evaluated through acute ecotoxicity tests with the aquatic microcrustacean Daphnia pulex (D. Pulex). Results showed that there was no cytotoxic activity for all tested SOF concentrations. Genotoxic responses by all the SOF samples were at same level, except for the HVO13 which was weaker in the absence of the enzymes. The addition of the FPG and Endo III enzymes resulted in a significant increase in the comet tail, indicating that the DNA damage from SOF for all tested fuel blends involves oxidative damage including a higher level of oxidized purines for ULSD and Bu13 in comparison with HVO blends, but the oxidized pyrimidines for HVO blends were slightly higher compared to Bu13. The WSF did not show acute ecotoxicity for any of the fuels. Unlike other samples, Bu13-derived particles significantly increase the BaP-TEQ. The contribution to the genotoxic activity and oxidative DNA from SOF was not correlated to BaP-TEQ, which means that the biological activity of PM might be affected also by other toxic compounds present in particulate phase.

Response surface methodology (RSM) based experimental and model analysis of diethyl ether-biodiesel-diesel blends with exhaust gas recirculation (EGR) on stationary diesel engine

In compliance with proposed targets of green energy and reduced emissions during the Glasgow summit, the study of blended fuels in internal combustion engines is of great significance. To address this issue, a detailed study of the engine performance and exhaust emissions has been conducted with ternary fuel blends of diethyl ether (DEE), waste soybean cooking oil (WSCO) biodiesel, and ultra-low sulfur diesel (ULSD). Ternary blends were prepared by adding 0–15% v/v DEE with the B35 blend (35% v/v WSCO biodiesel + 65% v/v ULSD), and tests were carried out with 15% EGR. The RSM based modeling and experimental approaches have been used for analysis. With a desirability of 0.961, the ternary blend DEE10B35EGR15 (10% v/v DEE + 90% v/v B35 at 15% EGR) was found to be an optimal blend. The measured responses are 0.272 kg/kWh, 31.47%, 18.94 HSU%, 91 ppm, 0.030%, and 24 ppm for brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), smoke, nitrogen oxides (NOx), carbon monoxide (CO), and hydrocarbon (HC) emissions, respectively. An innovative approach to analysis and quantifying the responses to ternary blends with EGR has been presented in the form of mathematical equations for future use and scope.

Synthesis of 2-Hydroxyethyl Esters from Castor Oil as Lubrication Bio-Additive Candidates for Low-Sulfur Fossil Diesel

The present work aims to study the synthesis of 2-hydroxyethyl esters from castor oil and its lubrication properties, promising as a lubrication bio-additive in low sulfur diesel fuel. This compound has been successfully synthesized from castor oil and ethylene glycol. The oil to ethylene glycol molar ratio was adjusted to 1:10, and the catalyst loading was used at 9% mole oil. Then, the mixture was refluxed for 5 h. The product components were characterized using GC-MS. The standard ASTM method was used to study the kinematic viscosity and lubrication. The product was dominated by 2-hydroxyethyl esters (94.16%), di-ester (1.12%), and cyclic ester (1.92%). The analysis of friction coefficient and wear scar diameter (WSD) using High-Frequency Reciprocating Rig (HFRR) shows the coefficient of friction and WSD of the product better than reference diesel fuel. From the results of this study, the 2-hydroxyethyl ester of castor oil, especially 2-hydroxyethyl ricinoleate, is the main responsible for the lubricating properties. Thus, 2-hydroxyethyl esters of castor oil can be proposed as an alternative bio-additive to improve the lubrication of low-sulfur fossil diesel fuels.