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In the present work, mechanistic pathways and kinetics of catalytic dehydration of ethanol were investigated in a closed batch reactor for the formation of diethyl ether, and ethylene over the synthesized NiO loaded HZSM-5 in the range of 160–240 °C. The effect of the presence of water on reaction performance was also evaluated. No significant negative impact of water over diethyl ether yield was observed up to 1:1 ethanol–water molar ratio. The proposed two-step kinetic model highlights the mechanistically essential comparison between the strong (Brønsted) and weak (Lewis) acid sites of catalyst for ethanol conversion to diethyl ether. Intramolecular dehydration of ethanol over strong acid sites led to ethylene formation. Enhancement of weak acid sites due to NiO loading over HZSM-5 led to interestingly higher yields of diethyl ether by a combination of ethylene and ethanol. Optimal consideration for maximum conversions was observed with high reusability. Graphical abstract for ethanol dehydration on Ni-HZSM-5 catalyst. [ABSTRACT FROM AUTHOR]

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The aim of the present investigation is to examine the characteristics of diesel engine for varying concentrations of diethyl ether (DEE) as an oxygenated additive in repurpose used cooking oil (RUCO) biodiesel and diesel blends. In the beginning, several pilot experimentations are carried out on diesel and B20 blend. Afterward, 0.8%, 1.6%, 2.4%, 3.2%, and 4% of DEE was blended with biodiesel/diesel. The IS standards are followed for investigating the various properties of biodiesel blends. Property investigation results revealed that the increasing concentration of DEE reduces the density, viscosity, calorific value, flash point with increase in cetane number. All the prepared blends are examined on water-cooled diesel engine at six distinct loads and constant engine speed. The investigation revealed that the BTE (brake thermal efficiency) increased by 16.06% while BSFC (brake specific fuel consumption) decreased by 4.12% for 0.8% concentration of DEE in a blend when contrasted with diesel. All tested fuel shows nearly the same trend of BSEC at all loading conditions and compression ratios. Further, the CI engine fueled with biodiesel-DEE-diesel blends has shown 20.41%, 34.69%, and 23.33% a maximum reduction in CO, HC, and NOx emissions as compared to diesel fuel at notable working conditions. The CO2 emission reduced in ternary blends due to lower carbon content in the blend. It can be noted that the minimum 0.8% concentration of DEE at CR15 in the ternary blend provided significant increment in BTE as 16.06%, with a 4.12% reduction in BSFC while CO, HC and NOx emissions minimized by 15.07%, 3.45%, and 14.70% than that of diesel fuel. In minimum concentration of DEE, the A0.8B19.2 blend provided luminous results in both performance and emission characteristics at CR15. [ABSTRACT FROM AUTHOR]

As an alternative fuel for the compression ignition engine, the biodiesel blended with diesel at low ratios is a widespread practice that alleviates exhaust emissions and aids in managing the fossil fuel crisis. However, deterioration in performance and combustion with an upsurge in the NOx emissions restrict the application of a higher ratio or pure biodiesel. Hence, this analysis aims to examine and combine distinctive benefits associated with different additives in a blend with biodiesel for maximum replacement of diesel. Maintaining one-half (50% (v/v) of diesel ratio fixed, various combinations of Bael (Aegle marmelos) seed oil biodiesel (B), and additives: Graphene nanosheets (GN), oxygenated diethyl ether (DEE in % v/v) are prepared and tested. The experimentation carried out in two phases, 1) finding the optimum blend (biodiesel-additives) and 2) investigating the performance and emission characteristics of the engine fueled by blends in comparison to diesel. The new additive GN is synthesized using a facile and greener method at room temperature. Results revealed that the blend comprising of biodiesel with dual additives shows improved performance and emission characteristics compared to without additives, any single additive, and pure diesel. The optimum improvement of CO by 41%, NOx by 13.5%, particulates by 45%, UHC by 39%, peak BTE by 3%, BSFC by 5.5% found with the optimum blend (D50+ B35+ GN100 ppm+DEE15). Hence, half of the diesel replaced by the optimum combination, besides a significant positive effect on the atmosphere. [ABSTRACT FROM AUTHOR]

Background: Marine sponges (phylum Porifera) are sessile filter-feeders from the ocean that are becoming the wealthiest sources of pharmacologically active compounds. Objectives: Our objectives are to identify bioactive compounds from marine sponges (Xestospongia exigua, Xestospongia muta, and Iotrochota baculifera) and to determine their antibacterial activity. Materials and Methods: Methanolic crude extracts were subjected to two-steps fractionation: first, solvent partitioning was conducted using diethyl ether and butanol, followed by column chromatography. The resulting fractions were tested for antibacterial activity against four bacterial strains (Staphylococcus aureus ATCC 25923, Micrococcus luteus ATCC 4698, Escherichia coli ATCC 11775, and Salmonella typhimurium ATCC 14128). The fractions were subsequently profiled using High-Performance Thin Layer Chromatography (HPTLC), and the component of active sub-fractions (SF) was identified using Gas Chromatography- Mass Spectrometry (GC-MS). Results: Although no antibacterial activity was recorded of the methanolic extracts in all marine sponges samples, the response towards diethyl ether extracts of X. exigua was strong. Out of 17 sub-fractions of diethyl ether profiled, three sub-fractions, i.e. 5, 13, and 14 were active. GC-MS identified five compounds in SF 5, four compounds in SF 13, and three compounds in SF 14. Furthermore, SF 13 and SF 14 could inhibit the growth of all bacteria tested, indicating a broad-spectrum activity. On the contrary, SF 5 showed selective inhibition only to E. coli and S. typhimurium, indicating narrow-spectrum activity. Conclusion: Bioactive SF 13 of X. exigua has a high potential as an antibacterial agent but in vitro assessment such as cytotoxicity against mammalian cell lines is needed to determine the toxicity and drug response. [ABSTRACT FROM AUTHOR]

In the present work, the palladium (Pd) modification and supporting effect of W/TiO2 catalysts on catalytic ethanol dehydration to ethylene and diethyl ether were investigated. The Pd modification with different sequence of Pd and W impregnation on the catalysts was prepared by the incipient wetness impregnation technique. The catalyst characterization and activity testing revealed that the different sequence during impregnation influenced the physicochemical properties and ethanol conversion of catalyst. The differences in structure and surface properties were investigated by XRD, BET, SEM, EDX, XPS and NH3-TPD. Upon the reaction temperature between 200 to 400°C, it was found that the conversion increased with increasing of temperature for all catalysts. The Pd incorporated into catalysts enhanced the ethanol conversion depending on the sequence of impregnation. At low temperature (ca. 200 to 300°C), diethyl ether is a major product and the Pd modification over W/TiO2 catalyst resulted in increased diethyl ether yield. This is because an increase of ethanol conversion was obtained with Pd modification, while diethyl ether selectivity did not change. This can be attributed to the higher amount of weak acids sites present after Pd modification into catalyst. Among all catalysts, the PdW/TiO2 catalyst (coimpregnation) achieved the highest diethyl ether yield of 41.4% at 300?. At high temperature (ca. 350 to 400°C), ethylene is the major product. The W/Pd/TiO2 catalyst (with sequential impregnation of Pd on TiO2 followed by W) exhibited the highest ethylene yield of 68.1% at 400°C. It can be concluded that the modification of Pd onto W/TiO2 upon different sequence of Pd and W impregnation can improve the diethyl ether and ethylene yield in catalytic ethanol dehydration. [ABSTRACT FROM AUTHOR]

This study was compiled from the results of various researches performed on using diethyl ether as a fuel or fuel additive in diesel engines. Three different techniques are used, the reduction of the harmful exhaust emissions of diesel engines. The first technique for the reduction of harmful emissions has improved the combustion by modification of engine design and fuel injection system, but this process is expensive and time-consuming. The second technique is the use of various exhaust gas devices like catalytic converter and diesel particulate filter. However, the use of these devices affects negatively diesel engine performance. The final technique to reduce emissions and also improve diesel engine performance is the use of various alternative fuels or fuel additives. The major pollutants of diesel engines are nitrogen oxides and particulate matter. It is very difficult to reduce nitrogen oxides and particulate matter emissions simultaneously in practice. Most researches declare that the best way to reduce these emissions is the use of various alternative fuels i.e. natural gas, biogas, biodiesel, or the use of fuel additives with these alternative fuels or conventional diesel fuel. Therefore, it is very important that the results of various studies on alternative fuels or fuel additives are evaluated together for practice applications. Especially, this study focuses on the use of diethyl ether in diesel engines as fuel or fuel additive in various diesel engine fuels. This review study investigates the effects of diethyl ether on the fuel properties, injection, and combustion characteristics. [ABSTRACT FROM AUTHOR]

In this paper, thermal diffusion states of pure diethyl ether and its mixture with cellulose dinitrate tripolymer were uncovered by LAMMPS-based Molecular Dynamic (MD) simulations. Those MD simulations were generally performed through specified ReaxFF reactive force field to obtain the properties of the chemical system such as molecular energy, density, mean square displacement (MSD) and molecular coordinate. The result of MD simulations presented the clear superheating phenomenon of pure liquid diethyl ether system in the studied environment. The obtained phase transition point was much higher than the reported one. The deviation between two temperatures was about 132.369 K. It was also demonstrated that the transition process was associated with the sharp increment of potential energy, volume, diffusion coefficient and cohesive energy. However, the split of these diethyl ether molecules was not uniform. The cluster-like transition state was observed before the end of the vaporing process (460 K). As for the addition of cellulose dinitrate tripolymer, these molecules were not agglomerated in the simulated organic mixture. However, the diffusion of cellulose dinitrate tripolymer was much weaker than those diethyl ether molecules. While the concentration of cellulose dinitrate tripolymer was higher, molecular interactions of this organic mixture were consequently improved, and this further limited the diffusion behavior of the entire chemical system. It could be concluded that the diffusion behavior of the entire organic system was decreased with more amount of cellulose dinitrate tripolymer molecules. [ABSTRACT FROM AUTHOR]

A novel highly stretchable gas sensor is reported that is based on popup antenna reconfiguration due to the strain induced by the swelling of a polydimethylsiloxane (PDMS) substrate when exposed to diethyl ether. When the swollen substrate is removed from the volatile solvent environment, the PDMS volume increase is reversed leading to compressive stress in an attached antenna transforming a 2D structure to a 3D structure through mechanically induced shaping. This provides a low cost and simple route to tune the antenna resonant frequency and gain in direct response to a chemical stimulus. Our proposed solvent sensor is able to measure 0 to 60% PDMS swelling corresponding to diethyl ether concentrations up to 1620 ppm via a resonant frequency shift from 4 to 2.4 GHz. A fatigue life study indicated 103.5 life cycles which demonstrates the durability of these sensors to accommodate large strain and repeatability of the sensing process. Multiphysics Finite Element Method (FEM) modelling of the mechanical and RF simulations along with analytical results based on an equivalent circuit model were in good agreement with experimental data and demonstrate the potential of these structures as sensors. [ABSTRACT FROM AUTHOR]

Blending biodiesel–diesel blends with alternative fuels such as butanol and diethyl ether becomes an interesting area of research. Butanol is becoming a popular fuel due to its renewable nature and superior properties compared to ethanol. Diethyl ether can be considered as a renewable fuel as it can be produced from bioethanol through easy dehydration process. This paper aims to study the physicochemical properties of biodiesel produced from Hemp (Cannabis sativa L.) and its blends with Euro diesel, butanol and diethyl ether. Furthermore, characterizations such as DSC, FT-IR, UV–Vis and TGA were also analyzed. Most of the properties of biodiesel satisfy EN 14214 and ASTM D6751 standards except iodine value and oxidation stability due to the high degree of unsaturation (128.549). Blending of hemp biodiesel with Euro diesel, butanol and diethyl ether improved the cold flow properties, kinematic viscosity and density. However, flash point decreased dramatically specially when blending with diethyl ether due to its low flash point. Therefore, care should be taken when handling or transporting biodiesel–diesel–diethyl ether blends. This work supports that blending Hemp methyl ester with Euro diesel, butanol and diethyl ether as ternary blends (up to 20%) can be considered as alternatives to fossil diesel in CI diesel engines. Therefore, it is recommended that engine, emissions and combustion characteristics of all blends shall be further investigated. [ABSTRACT FROM AUTHOR]

Some researches in wild mammals require methods that enable to handle the animals living in wild conditions, without affecting negatively the animals, or the researchers. These methods include the chemical immobilization, which has not been enough documented when handling wild rodents of the Sigmodontinae subfamily (Cricetidae). Therefore, this research evaluated the use of diethyl ether when handling Sigmodontinae rodents out in the countryside. It compared the induction time to the anesthesia recovery time between species, genders, and type of environments. A total of 289 animals were caught and anesthetized from six species in the Chingaza National Natural Park. The anesthesia induction times were different between Microryzomys minutus, Neomicroxus bogotensis, Thomasomys laniger y Thomasomys niveipes (F3; 552 = 9.36; p < 0.05). Likewise, the anesthesia recovery times were different between the same species (H = 9.59; p = 0.022). No difference was found in the induction times and the anesthesia recovery times between genders, neither for the types of environment. Total mortality was 4.5%. None mucosal secretions, vomit, or cardiac/respiratory complications were observed in the anesthetized animals. These subjects were caught again and they did not show any alterations in their behavior or physical aspect indicating affection derived either from the anesthesia or the previous handling under captivation. Anesthesia with diethyl ether can be a quick and safe choice when it comes to immobilize and handle Sigmodontinae rodents during short procedures out in the countryside, when carrying out population studies or wildlife monitoring programs. [ABSTRACT FROM AUTHOR]

This study aims to investigate the catalytic behaviors on W/TiO2 catalysts having different phases of TiO2 towards catalytic dehydration of ethanol to higher value products including ethylene, diethyl ether, and acetaldehyde. In fact, TiO2 support with different crystalline phases can result in differences of physico-chemical properties of the catalyst. Therefore, the present work reports on the catalytic behaviors that were altered with different phases of TiO2 in catalytic ethanol dehydration to diethyl ether or ethylene as a major product. To prepare the catalysts, three different phases [anatase (A), rutile (R), and mixed phases (P25)] of TiO2 supports were impregnated with 10 wt% of tungsten (W). It was found that the W/TiO2-P25 catalyst revealed higher activity among other catalysts. At 300 °C, all catalysts can produce the diethyl ether yield of 24.1%, 22.8%, and 10.6% for W/TiO2-P25, W/TiO2-A, and W/TiO2- R catalysts, respectively. However, when the reaction temperature was increased to 400°C, ethylene is the major product. The W/TiO2-P25 and W/TiO2-A catalysts render the ethylene yield of 60.3% and 46.2%, respectively, whereas only 15.9% is obtained from W/TiO2-R catalyst. The most important parameter influencing their catalytic properties appears to be the proper pore structure, acidity, and distribution of W species. [ABSTRACT FROM AUTHOR]

Background and Aims General anaesthetics are compounds that induce loss of responsiveness to environmental stimuli in animals and humans. The primary site of action of general anaesthetics is the nervous system, where anaesthetics inhibit neuronal transmission. Although plants do not have neurons, they generate electrical signals in response to biotic and abiotic stresses. Here, we investigated the effect of the general volatile anaesthetic diethyl ether on the ability to sense potential prey or herbivore attacks in the carnivorous plant Venus flytrap (Dionaea muscipula). Methods We monitored trap movement, electrical signalling, phytohormone accumulation and gene expression in response to the mechanical stimulation of trigger hairs and wounding under diethyl ether treatment. Key Results Diethyl ether completely inhibited the generation of action potentials and trap closing reactions, which were easily and rapidly restored when the anaesthetic was removed. Diethyl ether also inhibited the later response: jasmonic acid (JA) accumulation and expression of JA-responsive genes (cysteine protease dionain and type I chitinase). However, external application of JA bypassed the inhibited action potentials and restored gene expression under diethyl ether anaesthesia, indicating that downstream reactions from JA are not inhibited. Conclusions The Venus flytrap cannot sense prey or a herbivore attack under diethyl ether treatment caused by inhibited action potentials, and the JA signalling pathway as a consequence. [ABSTRACT FROM AUTHOR]

Electronic structure calculations and transition state theory are used to compute rate coefficients for the low-temperature oxidation of diethyl ether. Additional rate coefficients are computed to account for rovibrationally excited species that react with O 2 prior to thermalization in a process known as non-Boltzmann reactions. A detailed, low-temperature kinetic mechanism for DEE combustion is developed. Ignition delay curves are computed using two mechanisms, one that includes only thermal reactions and a second that also includes 8 non-Boltzmann reactions. Simulations suggest that at an initial pressure of 1 atm and temperatures below 800 K, the inclusion of non-Boltzmann reactions decreases the predicted ignition delay by a factor of 2 or more. As the pressure increases, the effective contribution of these reactions diminishes. These results suggest that non-Boltzmann phenomena can have a significant effect on real-world applications. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) is recognized as a carbon-free hydrogen-carrier fuel with a high content of hydrogen atoms per unit volume. Recently, ammonia has received increasing attention as a promising alternative fuel for internal combustion engine and gas turbine applications. However, the viability of ammonia fueling future combustion devices has several barriers to overcome. To overcome the challenge of its low reactivity, it is proposed to blend it with a high-reactivity fuel. In this work, we have investigated the combustion characteristics of ammonia/diethyl ether (NH 3 /DEE) blends using a rapid compression machine (RCM) and a constant volume spherical reactor (CVSR). Ignition delay times (IDTs) of NH 3 /DEE blends were measured using the RCM over a temperature range of 620 to 942 K, pressures near 20 and 40 bar, equivalence ratios (Φ) of 1 and 0.5, and a range of mole fractions of DEE, χ DEE , from 0.05 to 0.2 (DEE/NH 3 = 5 – 20%). Laminar burning velocities of NH 3 /DEE premixed flames were measured using the CVSR at 298 K, 1 bar, Φ of 0.9 to 1.3, and χ DEE from 0.1 to 0.4. Our results indicate that DEE promotes the reactivity of fuel blends resulting in significant shortening of the ignition delay times of ammonia under RCM conditions. IDTs expectedly exhibited strong dependence on pressure and equivalence ratio for a given blend. Laminar burning velocity was found to increase with increasing fraction of DEE. The burnt gas Markstein length increased with equivalence ratio for χ DEE = 0.1 as seen in NH 3 -air flames, while the opposite evolution of Markstein length was observed with Φ for 0.1 < χ DEE ≤ 0.4, as observed in isooctane-air flames. A detailed chemical kinetics model was assembled to analyze and understand the combustion characteristics of NH 3 /DEE blends. [ABSTRACT FROM AUTHOR]

[Display omitted] • Impact of diethyl ether on soot nanostructures studied for two diethyl ether-diesel blends. • Increasing diethyl ether content leads to higher disorder in nanostructures. • TGA curves reveal improved soot reactivity with moderate increase in diethyl ether content. In accordance with the European commission's renewable energy proposal for 2030, advanced biofuels should be blended at a minimum of 3.6 % with conventional fuels used for powering internal combustion engines. Ethers, which may be produced using modern production methods from sustainable sources like biomass, may be crucial in this regard in the future. This study demonstrates the impact of diethyl ether as a blend component (mixed with diesel) on the characteristics of the soot generated from the diethyl ether-atmospheric diesel's combustion. The soot used in this work came from a smoke point lamp that burned a mixture of diesel and diethyl ether as per ASTM D1322 standard. Diethyl ether (DEE) and diesel (D) were combined in the following blends: DEE5D (5 % diethyl ether and 95 % diesel v/v), and DEE20D (20 % diethyl ether and 80 % diesel v/v). The obtained soot was characterized in detail using the following: elemental analyzer, X-Ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), RAMAN spectroscopy, thermogravimetric analysis (TGA), and proton nuclear magnetic resonance (1H NMR) spectroscopy. According to the results from XRD and Raman spectroscopy, the soot nanostructure is influenced by the amount of diethyl ether present in the mixture, which raises the reactivity. The results of the elemental analyzer and 1H NMR matched those of the TGA's soot reactivity (oxidations). The results from the SEM and TEM tests, however, were not enough to support the experimental findings. [ABSTRACT FROM AUTHOR]

• Combined a shock tube with a laser absorption system for the combustion diagnostics. • Temperature, CO, CO 2 , H 2 O, NH 3 , and NO time-histories were simultaneously measured during ammonia/oxygenated hydrocarbons. • Kinetics models are detailly analyzed and improved by updating the rate constants of some reactions. Blending ammonia with highly active fuels (hydrogen, hydrocarbons, oxygenated hydrocarbons, etc.) has been identified as an efficient way to improve the mixture's reactivity. In this study, the temperature, CO, CO 2 , H 2 O, NH 3 , and NO time-histories were measured simultaneously during the oxidation of ammonia/ethanol and ammonia/diethyl ether (DEE) blends (equivalence ratio ϕ ∼ 1.2) using mid-infrared laser absorption spectroscopy behind reflected shock waves. Various models (ten for ammonia/ethanol and three for ammonia/DEE) were selected to perform the simulation and compared with the measurements. The predictions are very different for both mixtures, among which the CRECK model was selected to perform discussion and kinetics analyses for the ammonia/ethanol mixture and the Shrestha 2022 model was selected for the ammonia/DEE mixture. The CRECK model performs well in predicting the temperature rise/plateau, H 2 O formation rate/plateau, CO consumption rate/plateau, and CO 2 formation rate. However, it underpredicts the CO formation rate and slightly overpredicts the CO 2 plateau and NH 3 consumption rate; for the NO time-history, the CRECK model well captures the rapid NO formation but underpredicts the near-equilibrium NO concentration and gives an unnormal initial NO production. The Shrestha 2022 model accurately predicts the plateaus of temperature and H 2 O, but significantly underpredicts the reactivity of the ammonia/DEE mixture and overpredicts the near-equilibrium NO concentration. According to the kinetics analyses, key reactions affecting the species' time-histories were selected. Fourteen reactions in the CRECK model and eight reactions in the Shrestha 2022 model were updated by the reported data or estimations to improve the predictions. However, discrepancies still exist, which are mainly located in the CO formation and NH 3 consumption rates. Further effort should mainly focus on these two aspects, as well as the interactions between oxygenated hydrocarbons and ammonia at high temperatures. [ABSTRACT FROM AUTHOR]

• Combustion characteristics of DEE, WCO biodiesel, and jet A-1 investigated in a LPP system. • DEE addition significantly improves combustion characteristics. • NO x , CO, and UHC levels reduced for W20D20 by 38.4%, 68%, and 69.6%, respectively. This paper is a lab-scale experimental study of the impact of employing diethyl ether (DEE) as an additive to waste cooking oil biodiesel with Jet A-1 on the combustion as well as emission features of a swirl-stabilized premixed flame. First, waste cooking oil biodiesel with a volume fraction of 20% was blended with Jet A-1 and symbolized as W20. Then, diethyl ether with a volume fraction of 20% was blended with 20% biodiesel and 60% Jet A-1, symbolized as W20D20. The three test fuels (W20, W20D20 blend, and pure Jet A-1) were premixed with preheated air and pre-vaporized before being admitted to the vertical cylindrical combustor having an inner diameter of 150 mm and a length of 500 mm via a swirl burner (radial type) of 0.55 swirl number and 8 straight vanes with an angle of 45°. Local flame temperatures and emissions were measured and recorded at 350 °C of preheated air with a constant equivalence ratio (φ) of 0.85. According to the findings, a relatively wide range of flame temperatures was observed in the flame of the W20 blend, while the W20D20 blend had a flame temperature distribution very close to that of the Jet A-1. The W20D20 blend reduced UHC emissions by 69.6%, CO emissions by 61.4%, and NO x emissions by 12.5% relative to Jet A-1 at the combustion chamber outlet. Overall, adding DEE to biodiesel significantly impacts both combustion and emission profiles. [ABSTRACT FROM AUTHOR]

• In-situ IR characterization shows more C x H y * species from cracking of butanol while more unsaturated ketones from diethyl ether (DEE). • Reforming of ethanol generates more O-containing species, making coke more aliphatic and thermally unstable. • Reforming of butanol and DEE forms much more coke than from ethanol, due to aggregation of abundant carbonaceous intermediates. • Carbon-rich intermediates from butanol or DEE forms coke of aromatic nature with high crystallinity. • Coke from DEE is more defective with rough surface, while that from butanol is more graphitic with smooth surface. Molecular structures of organics play key roles in determining the tendency of coking and property of coke through governing reaction intermediates formed. Diethyl ether (DEE) can be produced from etherification of ethanol and has same carbon number with n-butanol (butanol), while they may show distinct coking behaviors in steam reforming (SR). Herein, SR of DEE, ethanol and butanol over Ni/SBA-15 catalyst were performed, aiming to probe impacts of ether functionality and length of carbon chain of the alcohols on coke formation. The results indicated that cracking of DEE formed C x H y * species and unsaturated ketone intermediates, serving as precursors of coke. Dissociative adsorption of butanol formed abundant C x H y * species even from 100 °C, due to its longer carbon chain and lower oxygen content. In comparison, abundant oxygen-containing intermediates were generated from degradation of ethanol and reactions with steam. Abundant C x H y * species from DEE and butanol prompted formation of more coke than that from ethanol (60.6 % of coke in the catalyst for DEE, 66.8 % for butanol and 32.9 % for ethanol). Moreover, the coke from SR of ethanol was thermally less stable than that from DEE or butanol, due to the involvement of more oxygen-containing intermediates, which resulted in more aliphatic coke of amorphous form in ethanol reforming. Additionally, the coke from DEE reforming was more defective with carbon nanotube form of thick walls and little internal cavity. The coke produced from butanol reforming was more graphitic and mainly in carbon nanotube form of smooth surface. Varied abundance of C x H y * and ketone species in reforming of DEE and butanol created such a difference. [Display omitted] [ABSTRACT FROM AUTHOR]

Improving the performance of internal combustion engines and ensuring the reduction of pollution by the application of an advanced technology constitutes one of the main keys for safe guarding nation's economy and health. In this context it is pertinent to note that in terms of brake thermal efficiency and brake specific fuel consumption, a single cylinder four stroke engine acquires a better performance with 15% diethyl ether (DEE) as an additive to diesel. Thus, the present investigation is motivated to compare the performance of the engine when run with diesel alone and when it is run with additives like ferric chloride (FeCl3) and diethyl ether. The experiments in the laboratory establish lowering emissions of CO, HC and smoke (excluding NO) with diesel and DEE additives compared to that with diesel and FeCl3 additives and diesel alone.

Within the Waste2Fuel project, innovative, high-performance, and cost-effective fuel production methods from municipal solid wastes (MSWs) are sought for application as energy carriers or direct drop-in fuels/chemicals in the near-future low-carbon power generation systems and internal combustion engines. Among the studied energy vectors, C1-C2 alcohols and ethers are mainly addressed. This study presents a potential bio-derived ethanol oxidative coupling in the gas phase in multicomponent systems derived from hydrotalcite-containing precursors. The reaction of alcohol coupling to ethers has great importance due to their uses in different fields. The samples have been synthesized by the co-precipitation method via layered double hydroxide (LDH) material synthesis, with a controlled pH, where the M(II)/M(III) ≈ 0.35. The chemical composition and topology of the sample surface play essential roles in catalyst activity and product distribution. The multiple redox couples Ni2+/Ni3+, Cr2+/Cr3+, Mn2+/Mn3+, and the oxygen-vacant sites were considered as the main active sites. The introduction of Cr (Cr3+/Cr4+) and Mn (Mn3+/Mn4+) into the crystal lattice could enhance the number of oxygen vacancies and affect the acid/base properties of derived mixed oxides, which are considered as crucial parameters for process selectivity towards bio-DEE and bio-butanol, preventing long CH chain formation and coke deposition at the same time.

The objective of this work was to compare the effect of diethyl ether (DEE) and methyl tertiary-butyl ether (MTBE) addition to biodiesel and diesel blends on diesel engine. The ethers concentration have been varied in proportion of 5% and 10% on volume basis with biodiesel by keeping the diesel concentration as 50% for all ternary blends preparation. Experimental results revealed that D50-B45-DEE5 ternary blend has shown 5.3% increase in thermal efficiency compared to other ternary blends. On the other hand, D50-B45-MTBE5 and D50-B45-DEE ternary blends have reduced CO emission by 8.1% and 14.8% respectively when compared to high speed diesel fuel. Furthermore, the D50-B40-DEE10 blend and D50-B40-MTBE10 reduce the NOx emission by 32% and 8.8% when compared to HSD at maximum load condition. Significant reduction is noted in HC emission for all ether added ternary blends than that of HSD and biodiesel fuels. However, the smoke emission is decreased marginally for D50-B45-DEE5 than that of HSD fuel. Finally, it is evident that both the DEE and MTBE could be used as viable additive with diesel or biodiesel in binary and ternary forms for diesel engine applications. • 5–10% of diethyl and methyl tertiary butyl ether are used in ternary blends. • 5% of diethyl ether in ternary blend has shown higher brake thermal efficiency. • ➢8–15% of carbon monoxide emission is reduced for 5% of ethers addition. • ➢45% reduction in NOx emission is achieved by 10% diethyl ether addition. • ➢All ternary diesel-biodiesel-ether blends reduced the HC emission. [ABSTRACT FROM AUTHOR]

Abstract Higher-value chemicals can be produced from methane with small exergy losses by partial oxidation if the chemical conversion proceeds in an internal combustion engine (ICE) as a polygeneration process (Gossler and Deutschmann, 2015). Kinetics models are not sufficiently validated for the very fuel-rich and high-pressure conditions relevant for this process. Therefore, ignition delay times of fuel-rich methane/(additive)/air mixtures were measured in a shock tube at about 30 bar and temperatures between 600 and 1650 K. n -heptane and diethylether were used as additives to increase the reactivity of the fuel so that the polygeneration process can be realized in an ICE at HCCI conditions at lower compression temperatures. At ϕ = 2, measured ignition delay times agree well with simulations using different mechanisms from literature. Synthesis gas (CO, H 2) is the main product at these conditions (Sen et al., 2016). For the production of higher hydrocarbons, the equivalence ratio must be increased. Very fuel-rich mixtures (ϕ = 10) were used because the temperature increase during the reaction of these mixtures is quite low (<450 K), so that post-ignition temperatures stay below the lower limit of soot formation. Only for mixtures with n -heptane as additive, good agreement of measured and simulated ignition delay times is found. The other mixtures show strong deviations with all mechanisms. As a further parameter to improve and validate the mechanisms at ϕ = 10, product distributions after ignition were determined by sampling in the cooling phase with a fast-opening valve and GC/MS analysis. Besides H 2 and H 2 O, CO and higher hydrocarbons like C 2 H 2 , C 2 H 4 , C 2 H 6 , and C 6 H 6 were detected as main products. About half of the carbon of the consumed methane is converted to CO, the other half to higher hydrocarbons. The product distributions are well predicted by simulations. [ABSTRACT FROM AUTHOR]

• The synthesis of Co 3 O 4 with a certain amount of CoCO 3 nanorods is described. • The growth of Co 3 O 4 with numerous defects is ascribed to the DMSO-assisted synthesis. • The nanorods had good sensitive/selective sensing toward gaseous diethyl ether at 160 °C. • The superior sensor performance is ascribed to the nanorods with abundant porosity and Co 3 O 4 with numerous defects. Herein, the mesoporous Co 3 O 4 -based nanorods were obtained by heat treatment of dimethyl sulfoxide-assisted hydrothermal-synthesized products at 300 °C and probe the composition, structure and morphology by several instrumental techniques. Additionally, we investigate the ability of the nanorods to sense several gaseous organic compounds, such as diethyl ether, ethanol, and acetone, demonstrating that the sensor based on the nanorods exhibits long-term stability and excellent responsiveness to diethyl ether (detection limit =0.5 ppm) at an operating temperature of 160 °C. The formation of the nanorods and the mechanism of diethyl ether sensing are discussed in detail, and the superior sensor performance is ascribed to the nanorods with abundant porosity and Co 3 O 4 with numerous defects, which facilitates the adsorption of oxygen on the sensor surface. [ABSTRACT FROM AUTHOR]

Abstract More than half of the oil discovered in existing oil reservoirs is left behind after primary and secondary recovery. It is essential to increase oil recovery from existing fields to meet future oil demand. The injection of solvents, an established enhanced oil recovery (EOR) technique, has shown significant improvement in oil recovery over conventional water floods. However, injection of pure solvent slugs is expensive for field operators. To mitigate this problem, recent literature has proposed the use of brines that are saturated with mutual solvents (which dissolve in both oil and water phases). In this paper, we investigate the behavior of two mutual solvents, carbon dioxide (CO 2) and diethyl ether (DEE). We have performed several core-floods in sandstone and carbonate cores. Injecting CO 2 -rich brine (carbonated water) into sandstone cores did not improve oil recovery. However, there was an improvement in oil recovery as a result of carbonated water injection in carbonate cores, which also displayed significant plugging during the experiment. There was also a noticeable improvement in oil recovery in the case of DEE-rich brine, but without any plugging issues. Mutual solvents dissolved in oil, swelled oil, and decreased oil viscosity which mobilized the oil. The experimental work was corroborated with numerical modeling to reproduce the results of both the solvents. Although the simulator is capable of handling rock–fluid interactions, such as mineral dissolution, the exact nature of the grain mobilization and pore-throat plugging was not incorporated in the numerical model. As a result, the simulator was unable to fully mimic the experimental observations of carbonated water floods. In contrast, since there was no apparent nor significant rock-fluid interaction in the DEE-rich brine case, it was successfully matched by the simulator. Highlights • Water floods with dissolved mutual solvents (CO 2 and diethyl ether) are studied. • Injection of CO 2 -rich brine improved oil recovery in carbonates, but not in sandstones. • Injection of diethyl ether (DEE)-rich brine also improved oil recovery in carbonate cores. • There was plugging in CO 2 -rich brine floods, but not in the case of DEE. • Our compositional simulator could match the DEE experiments, but not the CO 2 ones. [ABSTRACT FROM AUTHOR]

Cement hydration occurs according to a sequence of reactions whose products have a direct influence on the working properties of concretes and mortars during their use. The understanding of the evolution of its formation is quite simple and focused on monitoring the identification of resulting hydrate formed and their corresponding quantification by content of bound water after hydration stoppage and drying at certain set periods of time. Among the more common techniques are the methods of direct drying, where free water is eliminated by evaporation or sublimation or by replacing the existing water with organic solvents and then evaporating them. The existing doubts about the effect of these treatments in the change of the hydrate composition make it difficult to obtain an accurate determination. This work aimed to assess the impact of the stoppage of the hydration reaction of CPV (cement Portland type V from Brazilian market) in the results obtained by freeze-drying or immersion in an organic solvent as isopropanol or acetone, followed by substitution for diethyl ether. This last step is aimed at dispensing with the need for elevated temperatures or other aggressive solvent elimination methods such as evaporation under low pressure. The hydration was monitored at the previously set periods, and the hydrated products were analyzed by thermogravimetry and X-ray diffractometry. The results indicate that the technique of immersion on isopropanol and drying with diethyl ether is the most suitable one, as it does not affect the hydrated product composition. [ABSTRACT FROM AUTHOR]

Plants are widely used in traditional medicine from the beginning of mankind because of its significant healing power and least side effects. The extraction and isolation of biologically active components from plants for the designing and synthesis of novel drugs became an emerging research area for years. Plants possess a large spectra of secondary metabolites such as flavonoids, tannins, terpenoids, alkaloids, phenolic acids etc. they are the major contributors of pharmacological activities shown by plants. Present study aimed at the ABTS radical scavenging and antimicrobial testing of flavonoid fractions from the fruit rinds of Terminalia bellirica. The effect of flavonoids from diethyl ether and ethyl acetate extracts against six bacterial strains and two fungal strains are evaluated by the agar well diffusion method. The results revealed that these flavonoid containing fractions possess excellent ABTS radical scavenging activity with very low concentrations and considerable antimicrobial potential when compared with their respective standards. [ABSTRACT FROM AUTHOR]

Abstract Conformations of diethyl ether (DEE) were studied at low temperatures in N 2 and Ar matrixes. Computations performed at B3LYP/aug-cc-pVDZ level of theory yielded three minima corresponding to tt , tg ± and g ± g ± conformers of DEE. Of the three, the tt and tg ± conformers of DEE were experimentally identified in N 2 and Ar matrixes. Furthermore, hydrogen bonded complexes of pyrrole (py) with DEE have been investigated using Density Functional Theory (DFT) and matrix isolation infrared spectroscopy. Computations performed at B3LYP level of theory using aug-cc-pVDZ basis set on pyrrole with tt and tg ± conformers of DEE gave py-DEE- tt and py-DEE- tg ± complexes, both characterized by N H⋯O interaction. Experimental evidence for the formation of py-DEE- tt and py-DEE- tg ± complexes was affirmed from the shifts in the N H stretching, N H bending regions of pyrrole and C O C and C H stretching regions of DEE. NBO analysis was carried out to understand the charge-transfer delocalization interactions in the conformers of DEE and its hydrogen bonded complexes. Graphical abstract Unlabelled Image Highlights • Computations yielded tt , tg ± and g ± g ± conformers of Diethyl ether (DEE). • The tt and tg ± conformers of DEE were experimentally identified. • Py-DEE- tt and Py-DEE- tg ± hydrogen bonded complexes were experimentally identified. • NBO analysis were carried out to understand the delocalization interactions in DEE and its complexes. [ABSTRACT FROM AUTHOR]

The catalytic ethanol dehydration of ethanol over the solvothermal-derived alumina catalysts was investigated in this study. First, alumina catalysts were synthesized by the solvothermal methods to obtain three different phase composition of alumina catalysts including γ-phase (G-Al), χ-phase (C-Al) and equally mixed χ-γ phases (M-Al). Then, all catalysts were modified with boron (G-Al-B, C-Al-B and M-Al-B). It was found that the boron modification increased the amounts of total acid sites and the ratio of weak to strong acid sites (WSR). The catalytic activity and product selectivity of six catalysts via catalytic ethanol dehydration at 200, 300, and 400 °C were measured. For all catalysts, it revealed that ethanol conversion increased with increased temperatures from 200 to 400 °C. At 200-300 °C, the unmodified catalysts tended to exhibit the higher catalytic activity than the boron-modified catalysts. However, at high temperature (400 °C), the boron modification tended to increase the catalytic activity, especially for the M-Al-B catalyst (complete ethanol conversion at 400 °C). Considering ethylene production, the M-Al-B exhibited the highest ethylene yield among other catalysts with 92% at 400 °C. For diethyl ether, it was observed that the M-Al catalyst gave the highest diethyl ether yield of 57% at 300 °C. This is because the boron modification increased the amounts of total acid sites, which can promote the production of ethylene, while this is not preferable for diethyl ether production, which is favored by weak acid sites. [ABSTRACT FROM AUTHOR]

Diesel engines are widely used for their low fuel consumption and better efficiency. An experimental investigation was carried out to establish the performance and emission characteristics of single cylinder diesel engine by using ethanol-ceric oxide blend. During initial first phase a series of experiments have to be done by using ethanol-ceric oxide blend with various ratios in diesel engine the performance characteristics have to be studied. For preparation of ethanol and cerium oxide, continuous magnetic stirring has to be done but the blend should not be diluted completely. So by another method sonication (ultrasonic bath) we used to reduce the separation of fuels. During second phase ethanol-ceric oxide-diethyl ether, prepared by using additive to reduce the separation of fuels, the performance and emission characteristics have to be done. By this investigation the ceric oxide acts as oxygen donating catalyst and provides oxygen for the oxidation of CO or absorbs oxygen for the reduction of NOx. The activation energy of cerium oxide leads to burn off carbon deposits within the engine cylinder at the wall temperature and it prevents the deposition of non-polar compounds on the cylinder wall results in reduction of HC emissions. The diethyl ether is used to improve the cetane number of fuel molecules. [ABSTRACT FROM AUTHOR]

In this work, diethyl ether (DEE) and compressed natural gas (CNG) port fuel injection (PFI) was investigated in direct injection (DI) compression ignition engine to determine the performance, combustion, and emission behaviors. In dual fuel mode, DEE and neat diesel were used as fuel energy, whereas in homogeneous charge compression ignition (HCCI) mode, DEE, and CNG were used as fuel energy. The engine behavior was analyzed for different inlet charge temperatures. Exergy analysis has been carried out for analyzing the various availability shares in the engine. The maximum brake thermal efficiency of the engine increased at peak load from 27.31% in neat diesel to 29.12% for dual fuel mode (D + CNG). Hydrocarbon and carbon monoxide emissions were reduced and oxides of nitrogen increased with the inlet charge heating mode. Maximum exergy efficiency was observed as 57.1% in dual fuel operation. The result of this work proves that CNG in dual and HCCI are effective for engine operation. [ABSTRACT FROM AUTHOR]

In this present work, diethyl ether, which is currently served as promising alternative fuel for diesel engines, was produced via catalytic dehydration of ethanol over H3PO4-modified γ-χ Al2O3 catalysts. The impact of H3PO4 addition on catalytic performance and characteristics of catalysts was investigated. While catalytic dehydration of ethanol was performed in a fixed-bed microreactor at the temperature ranging from 200 °C to 400 °C under atmospheric pressure, catalyst characterization was conducted by inductively coupled plasma (ICP), X-ray diffraction (XRD), N2 physisorption, temperature-programmed desorption of ammonia (NH3-TPD) and thermogravimetric (TG) analysis. The results showed that although the H3PO4 addition tended to decrease surface area of catalyst resulting in the reduction of ethanol conversion, the Al2O3 containing 5 wt% of phosphorus (5P/Al2O3) was the most suitable catalyst for the catalytic dehydration of ethanol to diethyl ether since it exhibited the highest catalytic ability regarding diethyl ether yield and the quantity of coke formation as well as it had similar long-term stability to conventional Al2O3 catalyst. The NH3-TPD profiles of catalysts revealed that catalysts containing more weak acidity sites were preferred for dehydration of ethanol into diethyl ether and the adequate promotion of H3PO4 would lower the amount of medium surface acidity with increasing catalyst weak surface acidity. Nevertheless, when the excessive amount of H3PO4 was introduced, it caused the destruction of catalysts structure, which resulted in the catalyst incapability due to the decrease in active surface area and pore enlargement. [ABSTRACT FROM AUTHOR]

Abstract Diethyl ether (DEE) has been recently suggested as a potential biofuel for compression-ignition engines that are known to be significantly controlled by low-temperature (LT) chemistry. However, the LT oxidation of DEE has not fully been understood in term of the formation of LT fuel-specific products. We have thus studied the oxidation of DEE by examining detailed profiles of its oxidation products under LT conditions (400–1100 K). To this end, we have used a dedicated experimental setup including a nearly-atmospheric jet-stirred reactor (JSR) coupled to online gas chromatography (GC). The experiments were complemented by measurements made with a JSR coupled to tunable synchrotron vacuum ultraviolet (SVUV) photoionization (PI) molecular-beam mass spectrometry (MBMS) for a cross-validation of the identification of important LT species. Experimental results indicate that DEE is very reactive; it starts to react around 425 K. DEE exhibits an unusual oxidation behavior with two negative temperature coefficient (NTC) zones in the JSR study. Because of this two-NTC observation, additional experiments were performed with a plug flow reactor (PFR) combined with electron ionization (EI)-MBMS, confirming this behavior in the two types of reactor. Moreover, about 20 oxidation species in C 1 C 4 range were detected with several intermediates containing 2-3 O-atoms. Acetic acid is found to peak at 525 K with a very large amount, suggesting that it is a key species in the early stage of DEE's LT oxidation. Possible DEE-consumption paths leading to acetic acid formation could play an important role in the oxidation mechanism of DEE. A new model is proposed based on the present experimental observations to include new primary LT reaction paths. The model reproduces the experimental phenomena quite well and enhances the understanding of the two-NTC-zone occurrence and of intermediates containing 2-3 O-atoms during the LT oxidation of DEE. [ABSTRACT FROM AUTHOR]

Physico-chemical properties of diethyl ether/linseed oil (DEE/LO) fuel blends were empirically tested in this article for the first time. In particular, kinematic viscosity (ν), density (ρ), lower heating value (LHV), cold filter plugging point (CFPP) and surface tension (σ) were examined. For this research diethyl ether (DEE) was blended with linseed oil (LO) in volumetric ratios of 10%, 20% and 30%. Obtained results were compared with literature data of diethyl ether/rapeseed oil (DEE/RO) fuel blends get in previous research in such a way looking on differences also between oil types. It was found that DEE impacts significantly on the reduction of plant oil viscosity, density and surface tension and improve low temperature properties of tested oils. In particular, the addition of 10% DEE to LO effectively reduces its kinematic viscosity by 53% and even by 82% for the blend containing 30% DEE. Tested ether reduces density and surface tension of LO up to 6% and 25% respectively for the blends containing 30% DEE. The measurements of the CFPP showed that DEE significantly improves the low temperature properties of LO. In the case of the blend containing 30% DEE the CFPP can be lowered up to −24 °C. For this reason DEE/LO blends seem to be valuable as a fuel for diesel engines in the coldest season of the year. Moreover, DEE/LO blends have been tested in the engine research. Based on results it can be stated that the engine operated with LO results in worse performance compared with regular diesel fuel (DF). However, it was found that these disadvantages could be reduced with DEE as a component of the fuel mixture. Addition of this ether to LO improves the quality of obtained fuel blends. For this reason, the efficiency of DEE/LO blend combustion process is similar for the engine fuelled with regular diesel fuel. In this research it was confirmed that the smoke opacity reaches the highest value for the engine fuelled with plant oils. However, addition of 20% DEE reduces this emission to the value comparable for the engine operated with diesel fuel.

How to achieve a fast and reliable cold start of diesel engines at extremely low temperatures is a significant and longstanding problem. In this study, a precise amount of diethyl ether was premixed in the intake to facilitate the starting at extremely low ambient temperatures down to −40 °C. The study investigated the effects of diesel fuel injection strategies, diethyl ether concentration, and ambient temperature on the cold-start performance. Additionally, an analysis was conducted on energy consumption and heat loss during the cold start period. The test engine could start quickly and steadily when diethyl ether was premixed in the intake. This was achieved by optimizing the diesel injection quantity to 60% of the original quantity and retarding the injection timing from 6 oCA BTDC to 2 oCA BTDC. The engine exhibited reliable starting at −40 °C when 2.0% v/v diethyl ether was premixed. However, excessive direct injection of diesel had an adverse effect on fuel ignition at such extremely low temperatures. Moreover, the electricity consumption was much lower with diethyl ether premixed in the intake than that with an electric intake heater, greatly reducing the requirements for starting batteries during the cold start under extremely low-temperature conditions. • Reduction in starting fuel quantity avoids detonation when DEE is premixed. • Diesel ignites in the first injection cycle with the aid of 2% DEE at −40 °C. • The diesel engine with 2% DEE premixed starts quickly and reliably at −40 °C. • Large starting fuel quantity is adverse to fuel ignition at extremely low temperature. • Premixing DEE reduces the requirement for starting battery at low temperature. [ABSTRACT FROM AUTHOR]

The dehydration of ethanol into diethyl ether over a SO 4 /SiO 2 catalyst was investigated. The SO 4 /SiO 2 catalysts were prepared by the sulfation method using 1, 2, and 3 M of sulfuric acid (SS1, SS2, and SS3) via hydrothermal treatment. This study is focused on the synthesis of a SO 4 /SiO 2 catalyst with high total acidity that can be subsequently utilized to convert ethanol into diethyl ether. The total acidity test revealed that the sulfation process increased the total acidity of SiO 2. The SS2 catalyst (with 2 M sulfuric acid) displayed the highest total acidity of 7.77 mmol/g, whereas the SiO 2 total acidity was only 0.11 mmol/g. Meanwhile, the SS3 catalyst (with 3 M sulfuric acid) has a lower total acidity of 7.09 mmol/g due to the distribution of sulfate groups on the surface having reached its optimum condition. The crystallinity and structure of the SS2 catalyst were not affected by the hydrothermal treatment or the sulfate process on silica. Furthermore, The SS2 catalyst characteristics in the presence of sulfate lead to a flaky surface in the morphology and non-uniform particle size. In addition, the surface area and pore volume of the SS2 catalyst decreased (482.56–172.26 m2/g) and (0.297–0.253 cc/g), respectively, because of the presence of sulfate on the silica surface. The SS2 catalyst's pore shape information explains the formation of non-uniform pore sizes and shapes. Finally, the activity and selectivity of SO 4 /SiO 2 catalysts in the conversion of ethanol to diethyl ether yielded the highest ethanol conversion of 70.01% and diethyl ether product of 9.05% from the SS2 catalyst (the catalyst with the highest total acidity). Variations in temperature reaction conditions (175–225 °C) show an optimum reaction temperature to produce diethyl ether at 200 °C (11.36%). [Display omitted] • The synthesis of SO 4 /SiO 2 from TEOS was carried out using hydrothermal treatment. • Conversion of ethanol into DEE using SO 4 /SiO 2 was higher compared to the SiO 2. • SS2 catalyst produced the highest ethanol conversion and DEE yield at 200 °C. • The synthesis of SS2 catalyst via hydrothermal showed higher activity than sol-gel. [ABSTRACT FROM AUTHOR]

[Display omitted] • Low temperature cracking of n-hexadecane is executed by DBD plasma. • Cracking of n-hexadecane produces more liquid light substances. • Diethyl ether is a better additive to assist in the cracking of n-hexadecane. • Diethyl ether is preferably added by the carrier gas. Innovative technologies for converting heavy oil into more environmentally friendly petroleum products are emerging as a result of growing concerns about climate change. Non-thermal plasma is a promising technology for this purpose due to its ability to use renewable energy sources at ambient temperature and its non-equilibrium nature. This study investigates the cracking of n-hexadecane, a model compound for heavy oil, using dielectric barrier discharge plasma assisted by liquid organic additives to generate light substances. The study compares the effects of three different liquid additives on the products, and diethyl ether is found to be the most favorable for generating light liquid chemicals. The effects of additive concentration, addition method, discharge time, and power on light product selectivity were also discussed. The results demonstrate that the method of bringing in the diethyl ether via the carrier gas can significantly inhibit the cracking of n-hexadecane to produce heavy substances and improve the yield of light substances and light product selectivity. The inlet diethyl ether concentration of 2.8 g/L, the discharge power of 19.2 W, and the discharge time of 15 min ensure a high yields of liquid light substances (287.5 mg) while maintaining the light product selectivity of 86.4% with the gas flow rate of 7.9 mL/min and the n-hexadecane conversion of 5.6%. Finally, the possible reaction pathways for the co-conversion of n-hexadecane and diethyl ether by plasma were discussed. [ABSTRACT FROM AUTHOR]

This article presents results of experimental study of diesel, rapeseed oil and three different blends of 10%, 20% and 30% diethyl ether addition to rapeseed oil, tested on VW Golf vehicle on chassis dynamometer Mustang MD-1750. Fuel consumption and emission tests were conducted at different testing conditions: idling, 50 km/h, 90 km/h, as also IM-240 cycle. The analysis of obtained results have shown reduction of engine power by 6.2%–17.3% and increase of fuel consumption by 0.6%–15.5% (based on testing conditions) for all blends based on DEE addition compared to RO, demonstrating better perspectives for low level blends. Emission tests have shown decrease of hydrocarbons and nitrogen oxides (NOx) for all blends with DEE content in almost all testing conditions and also slight increase of carbon monoxides and carbon dioxides compared to rapeseed oil. Largest decrease of NOx was observed during 90 km/h and cycle IM-240 reaching almost 24% reduction for 20DEE and 30DEE in comparison to neat RO.

Biofuels provide high oxygen content for combustion and do modify properties that influence the engine operation process such as viscosity, enthalpy of vaporization, and cetane number. Some requirements of performance, fuel consumption, efficiency, and exhaust emission are necessary for the validation of these biofuels for application in engines. This work studies the effects of the use of diethyl ether (DEE) in biodiesel-ethanol blends in a DI mechanical diesel engine. The blends used in the tests were B80E20 (biodiesel 80%-ethanol 20%) and B76E19DEE5 (biodiesel 76%-ethanol 19%-DEE 5%). Fossil diesel (D100) and biodiesel (B100) were evaluated as reference fuels. The results revealed similar engine efficiencies among tested fuels at all loads. The use of B100 increased CO and NOx and decreased THC compared to D100 at the three loads tested. B80E20 fuel showed an increase in NOx emission in comparison with all fuels tested, which was attributed to higher oxygen content and lower cetane number. THC and CO were also increased for B80E20 compared to B100 and D100. The use of B76E19DEE5 fuel revealed reductions in NOx and CO emissions, while THC emissions increased. The engine efficiency of B76E19DEE5 was also highlighted at intermediate and more elevated engine load conditions.

In this work, we investigated the role of solid-state dealumination by (NH4)2SiF6 (25% Al removal and 13% Si insertion), the impregnation of niobium (10, 18, and 25 wt. %) on dealuminated *BEA (DB) zeolite and their catalytic properties in ethanol and xylose transformations. Among all the studied catalysts, 18%Nb-DB showed increased mesoporosity and external areas. A leveling effect in the number and strength of the proposed two sites (Brønsted and Lewis) present in the catalyst (n1 = 0.24 mmol g−1, −ΔH1 = 49 kJ mol−1, and n2 = 0.20 mmol g−1, –ΔH2 = 42 kJ mol−1) in the catalyst 18%Nb-DB, might be responsible for its good activity. This catalyst presented the highest selectivity for diethyl ether, DEE (97%) with 61% conversion after 50 ethanol pulses at 230 °C (turnover number, TON DEE = 1.15). These features allowed catalytically fruitful bonding of the ethanol molecules to the neighboring sites on the channels, facilitating bimolecular ether formation through a possible SN2 mechanism. The same catalyst was active and selective for transformation of xylose at 180 °C, showing 64% conversion and 51% selectivity for furfural (TON Furfural = 24.7) using water as a green solvent.

The aim of this work is to analyze the effect of using diethyl ether (DEE) as an oxygenated additive of straight vegetable oils (SVOs) in triple blends with fossil diesel, to be used in current compression ignition (C.I.) engines, in order to implement the current process of replacing fossil fuels with others of a renewable nature. The use of DEE is considered taking into account the favorable properties for blending with SVO and fossil diesel, such as its very low kinematic viscosity, high oxygen content, low autoignition temperature, broad flammability limits (it works as a cold start aid for engines), and very low values of cloud and pour point. Therefore, DEE can be used as a solvent of vegetable oils to reduce the viscosity of the blends and to improve cold flow properties. Besides, DEE is considered renewable, since it can be easily obtained from bioethanol, which is produced from biomass through a dehydration process. The vegetable oils evaluated in the mixtures with DEE were castor oil, which is inedible, and sunflower oil, used as a standard reference for waste cooking oil. In order to meet European petrodiesel standard EN 590, a study of the more relevant rheological properties of biofuels obtained from the DEE/vegetable oil double blends has been performed. The incorporation of fossil diesel to these double blends gives rise to diesel/DEE/vegetable oil triple blends, which exhibited suitable rheological properties to be able to operate in conventional diesel engines. These blends have been tested in a conventional diesel engine, operating as an electricity generator. The efficiency, consumption and smoke emissions in the engine have been measured. The results reveal that a substitution of fossil diesel up to 40% by volume can be achieved, independently of the SVO employed. Moreover, a significant reduction in the emission levels of pollutants and better cold flow properties has been also obtained with all blends tested.

Diesel engine is widely used in the different applications of the modern life. Diesel fuel quality is an important indicator of the engine efficiency and exhaust emissions. However, the low cetane number of the commercial diesel resulting from improper refining processes lead to significant reduction in the engine efficiency. Hence, the aim of this study is to use diethyl ether to improve the fuel quality for better engine performance at lower engine emissions. Diethyl ether has been used at 5% percentage with commercial diesel, and the cetane number of the fuel was measured. Engine test was conducted at increasing speed to evaluate the engine performance and emissions. The study results show an improvement in the fuel cetane number from 49 to 51 with 5% diethyl ether. Furthermore, significant increase in engine power by about 10% has been recorded for the whole engine speed with slightly lower specific fuel consumption at low and medium engine speeds. Moreover, noticeable reduction in NOx emissions and CO emissions has been observed compared to commercial diesel. Therefore, it can be concluded that the utilization of diethyl ether as a fuel additive with commercial diesel can be considered for improving engine efficiency and control exhaust emissions.