Ethanol Fuel Research Articles

The Effect of Saccharin on SnNi Alloy: the Electrodeposition and its Electrocatalytic Activity in Ethanol Oxidation Reaction

The development of Direct Ethanol Fuel Cell (DEFC) has attracted much attention, as alternative energy sources due to its various advantages. However, among its various advantages, DEFC has several problems, such as the kinetics of the ethanol oxidation reaction. Transition metal-based catalysts such as nickel and tin are considered as potential catalysts for DEFC due to their oxophilic properties that can improve catalytic activity. In this study, the effect of saccharin on SnNi bimetallic alloy catalyst synthesized by electrodeposition method on copper wire substrate was investigated. SnNi samples were characterized by several techniques, including X-ray diffraction, Scanning electron microscopy, and energi dispersive X-ray spectrocopy. Saccharin addition had a significant effect on the morphology, crystallite size, and composition of the catalyst. The presence of saccharin causes the formation of more uniform particles and has a smaller size. The sample with the addition of saccharin had a smaller charge transfer resistance value 4.82 Ω, lower tafel slope by 115 mV/dec, and show higher jf/jb ratio by 0.55. Furthermore, as the current density decreases, the SnNi catalyst with saccharin has a slow decrease rate and higher stability than the SnNi catalyst without saccharin.

Outstanding Activity and Durability of Supported NiCo2O4 Nanoparticles for Direct Ethanol Fuel Cells

ABSTRACTThe rational design of noble metal‐free electrocatalysts represents one of the basic stones for fuel cell development. With the exploration of eco‐friendly nanomaterials for the investigated alcohol oxidation process, nickel‐based electrodes have been recognized as the most auspicious anodes with promoted activity and stability. In this work, a series of NiCo2O4 nanoparticles were deposited onto graphite sheets (NiCo2O4/T) introducing varied proportions of cobalt oxide species. Co‐precipitation protocol of the respective metallic hydroxides onto the carbonaceous support was followed with consecutive annealing in an air atmosphere at 400°C. The fabricated mixed metallic oxide nanopowder was physically studied using X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X‐ray analysis (EDX), X‐ray photoelectron spectroscopy (XPS), and selected area electron diffraction (SAED). Uniformly arranged nanoparticles were observed on graphite surface as evidenced by SEM and TEM. The cubic lattice structure of formed NiCo2O4 crystals was also confirmed by XRD through the defined peaks of binary metallic oxides clarifying their successful preparation scheme. The electrocatalytic properties of these NiCo2O4/T nanocatalysts were evaluated for oxidizing ethanol molecules in basic solution. Pronounced oxidation current densities were remarkably measured at NiCo2O4/T electrodes in relation to that at NiO/T. Differing the introduced cobalt oxide content into the synthesized nanocatalyst significantly controlled its catalytic performance. NiCo2O4/T‐20 exhibited the highest activity and stability among the prepared nanomaterials. Much decreased charge transfer resistances were also recorded at this electrode demonstrating its promoted electron transfer characteristics. This work could provide a reasonable route for the simple synthesis of comparable transition metallic oxides with promising attitudes for energy generation purposes.

Electrocombustion Characteristics of Iron Particle-Laden Methanol and Ethanol Droplets in a Direct Current Field

ABSTRACT This study investigates the electrocombustion and atomization behavior of single droplets (2.5 wt.% Fe) of ethanol (EtOH) and methanol (MeOH) fuels at the droplet scale. The experiments utilize a system with two opposing plate electrodes of varying distances (200, 150, and 100 mm) and both negative (↓) and positive (↑) polarizations within a vertical direct current (DC) electric field. The results show that for EtOH and EtOH/Fe droplets, the flame envelope changes to a spherical form at (↓) and (↑) polarizations at 100 mm plate spacing, while for MeOH and MeOH/Fe droplets, the flame envelope changes to a spherical form at (↓) and (↑) polarizations at 200, 150 and 100 mm plate spacing. Increasing electric field strength reduced the micro-explosion tendency of Fe particles in the flame region and the micro-explosion intensity of Fe particles was found to be higher in ethanol droplets than in methanol. No systematic relationship could be established between the electric field effect and the presence of Fe particles. The MeOH/Fe/150(↑) droplet exhibited the lowest extinction time of 1050 ms. The electric field fundamentally alters the secondary atomization process of the fuel droplets. Notably, the diameter regression of all MeOH-based fuel droplets deviates significantly from a linear relationship. The investigation into the combustion behavior of pure EtOH, MeOH, and their Fe-blended counterparts within an electric field environment suggests that MeOH and MeOH/Fe fuels exhibit superior combustion characteristics. However, further research is necessary to fully elucidate these findings.

Adoptability assessment of HCDI and RCCI modes in plug-in parallel hybrid electric vehicles using sustainable fuels and model-based torque structure calibration strategies

In this research, a comparative analysis of plug-in hybrid electric vehicle (PHEV) engine was conducted with two advanced low temperature combustion (LTC) techniques viz. Homogeneous charge with direct injection (HCDI) and reactivity-controlled compression ignition (RCCI), utilizing alternative fuels diethyl ether (DEE) and ethanol. This was attempted to exhibit the promising potential of LTC based PHEV to achieve the highest efficiency and low emissions. The experimental results disclosed that DEE powered HCDI can achieve superior thermal efficiency with an impressive peak torque of 14 Nm. On the other hand, ethanol powered RCCI produced a peak torque of 17.5 Nm with remarkable emission reduction characteristics, especially CO2. It was vindicated that HCDI-PHEV outperformed the RCCI-PHEV in terms of fuel economy despite both HCDI and RCCI being lower than the conventional diesel PHEV. The NOx emissions from HCDI were almost negligible. About 20 % lower nitrogen oxide (NOx) emissions were recorded for RCCI respectively as compared to diesel (36 g/s). HCDI and RCCI showcased about 2 and 1.3 times higher soot emissions than diesel (7.12 g/s). Fuel economy was improved by 15 % and 43 % respectively under HCDI and RCCI modes over the conventional diesel mode of PHEV operation. When the PHEV was operated continuously for about 3.5 h, the battery's SOC dropped from 80 % to 45 % under diesel operation, whereas it only reached 50 % and 60 % under RCCI and HCDI mode operation. Low fuel consumption characteristics, acceptable torque production capabilities and ultralow NOx reduction potential established HCDI as the preferable choice for PHEV over RCCI.

Study on the combustion characteristics and reaction mechanism of aluminum/alcohol-based nanofluid fuel

Enhancing the volumetric energy density of fuels is a crucial approach in the exploration of efficient energy sources. As a commonly used high-energy additive, Aluminum nanoparticles (Al NPs) holds broad application prospects. This study delves into the effects of Al NPs on the combustion characteristics of methanol and ethanol fuels through in-depth analysis of single droplet combustion and spray combustion experiments involving alcohol-based nanofluid fuels. The experiments revealed that adding Al NPs significantly enhances fuel combustion efficiency, shortening both the combustion life and ignition delay time. Spray combustion tests demonstrated that adding 2 wt% Al NPs increased the maximum and average flame propagation speeds of ethanol fuel spray by 48.93 % and 47.94 %, respectively, while the maximum explosion pressure rose from 0.66MPa to 0.83MPa, with a reduced time to reach peak explosion pressure by 106ms. Based on the SEM and XRD characterization results of the combustion residues and the analysis of flame morphology, a physical model of the alcohol-based nanofluid fuel spray combustion flame was established. Numerical simulations of the gas-phase kinetics model showed that the generation rates of radicals such as H, O, and OH were significantly increased with the addition of Al NPs, intensifying the combustion reaction. The findings provide a theoretical basis for future fuel design and combustion performance optimization.

Enhancing the Catalytic Activity of Pd Nanocatalysts for Anion Exchange Membrane Direct Ethanol Fuel Cells by Functionalizing Vulcan XC-72 with Cu Organometallic Compounds.

The most widely used support in low-temperature fuel cell applications is the commercially available Vulcan XC-72. Herein, we report its functionalization with the home-obtained mesityl copper (Cu-mes) and Cu coordinate (Cu(dmpz)L2) organometallic compounds. Pd nanoparticles are anchored on the supports obtaining Pd/CCu-mes, Pd/CCu(dmpz)L2, and Pd/C (on nonfunctionalized support). The polarization curves of the ethanol oxidation reaction (EOR) show that Pd/CCu-mes and Pd/CCu(dmpz)L2 promote the reaction at a more negative onset potential, i.e., E onset = 0.38 V/reversible hydrogen electrode (RHE), compared to 0.41 V/RHE of Pd/C. The mass current density (j m) delivered by Pd/CCu-mes is considerably higher (1231.3 mA mgPd -1), followed by Pd/CCu(dmpz)L2 (1001.8 mA mgPd -1), and Pd/C (808.3 mA mgPd -1). The enhanced performance of Pd/CCu-mes and Pd/CCu(dmpz)L2 for the EOR (and tolerance to CO poisoning) is attributed to a shift of their d-band center toward more negative values, compared to Pd/C, because of the formation of PdCu alloyed phases arising from the functionalization. In addition, laboratory-scale tests of the anion exchange membrane-direct ethanol fuel cell assembled with Pd/CCu-mes show the highest open circuit voltage (OCV = 0.60 V) and cell power density (P cell = 0.14 mW cm-2). As a result of its high catalytic activity, Pd/CCu-mes can find application as an anode nanocatalyst in AEM-DEFCs.

Educating Engineers on the Use of Renewable Ethanol Fuel as a Drop-in Replacement for Gasoline in Small Engines

The use of high-blend ethanol fuels to reduce emissions produced by on-road vehicles has been extensively studied. However, much less research has been done to study the effect of operating small off-road engines on high-blend ethanol fuel as a drop-in replacement for gasoline. Most small engine manufacturers only certify proper operation on low ethanol blends such as E10 (10% ethanol, 90% gasoline by volume). Most engineering students are unaware of the benefits that can be achieved when using high-blend ethanol fuel in small engines without substantial modifications. In this study, students conducted performance testing and analysis of a small engine using a dynamometer and a raw exhaust emissions analyser. The exhaust emissions and performance of the engine were evaluated using the U. S. Environmental Protection Agency (EPA) 6-mode duty cycle for small recreational engines (under 19 kW). Testing and analysis followed the recommendations of the SAE J1088 recommended practice. Students were motivated by the contemporary nature of the project and the use of commercially available equipment for testing. Further, students learned about the use of standardized testing to demonstrate the performance and emissions results.

Impact of agricultural and energy prices on the biofuels market through a VAR-VEC model

This study uses a Vector Autoregression - Error Correction Model to examine the price dynamics of Fatty Acid Methyl Ester (FAME) in the Portuguese market. The importance of this research is that failure to meet the targets of the Renewable Energy Directive jeopardizes Portugal's efforts to improve the sustainability of the transport sector. The results suggest that FAME prices are susceptible to fluctuations in agricultural commodities, ethanol, and fossil fuels, particularly diesel. Specifically for soy, FAME prices did not return to baseline levels by the end of the period, indicating a persistent impact. The volatility of FAME prices in response to ethanol and agricultural commodity prices underscores the need for strategic interventions to optimize these relationships. In the case of ethanol, this correlation could be strengthened, while in the case of agricultural commodities, feedstock diversification is essential to decouple FAME from first-generation biofuel sources and avoid competition with food crops. Moreover, biodiesel FAME, which serves as substitute and a complement to diesel, has a price sensitivity to changes in diesel prices. Policies and incentives to diversify feedstocks and promote advanced biofuels are essential for maintaining FAME's competitiveness and mitigating diesel price impacts.

Technoeconomic feasibility of producing clean fuels from waste plastics: A novel process model

Plastic waste is a problematic issue impacting the environment and human health. A proper recycling of plastics to valuable products is highly needed to meet the increase in energy demand. Plastics have high heating value; therefore, the thermochemical recycling of plastic waste is a valid and feasible approach. Recently, ethanol has attracted wide applications such as the conversion of ethanol to olefins, and hydrocarbons. It burns completely and cleanly, where it reduces the emissions of greenhouses compared to the usual fuels. Hydrogen and other higher hydrocarbons are also crucial in meeting the energy demand. In this study, the plastic waste, mainly polyethylene and polypropylene (due to their availability) were gasified using steam gasification process to produce syngas which then was further processed to hydrogen, ethanol, and other valuable liquid hydrocarbons. An alternative design is constructed integrating steam methane reforming (SMR) with plastic gasification to utilize the heat at the outlet of the gasifier and to enhance the syngas heating value. The two models were compared in terms of syngas heating value, energy analysis and economic analysis. The main parameters that have been evaluated are the production rate of fuel per total feedstock, total required heat, overall process efficiency, and fuel levelized production cost. The results indicated that Case 2 generates syngas with a higher heating value of 55 %, produces four times more H2, and comparable amount of ethanol and other fuels than Case 1. The analysis also revealed that Case 2 has a process efficiency that is 3 % better and a 37.5 % lower fuel production cost than Case 1. Overall, the design of Case 2 was found to be more efficient and cost-effective than the Case 1 design.

The Effect of Avgas and Ethanol Fuel Mixture on Fuel Spray Temperature

This research aims to examine the effect of the avgas-ethanol fuel mixture on the fuel spray temperature. The research was carried out using a pressurized tube which was sprayed into the mock up which was assumed to be an aircraft combustion chamber with a pressure of 2 bar and a distance of 7,73 cm which would later be sprayed using pure avgas, a mixture of avgas and ethanol namely A80E20 and A60E40 then added with a temperature sensor at the end nozzle, center of jet, and impact wall. The spray temperature can result in incomplete combustion and result in higher exhaust emissions and also damage to the engine if it does not match the temperature capacity of the combustion chamber walls. The spray temperature results for the A60E40 fuel mixture are the lowest temperature, namely 25o-18.2oC and knowing that the more fuel is mixed, the lower the temperature of the fuel.

Evaluating Lean Combustion Cycle Stability and Emissions in Spark Ignition Engines with Gasoline, Ethanol, and Methanol Blends

Abstract Fuels for vehicles account for a large portion of the world’s total energy demand, which in turn leads to increased carbon emissions. Ethanol and methanol are a fuel with a simple carbon chain and OH- bonds. It has similar properties to gasoline, and ethanol can be made from the fermentation of plant carbohydrates, called bioethanol. The advantage of using bioethanol is that it contributes to carbon neutrality. This paper will investigate the use of three manually blended gasoline ethanol and methanol (GEM) fuels in a spark ignition engine to address cycle-to-cycle variation (CCV), knock potential, and emissions with lean blend conditions. In the experiments conducted, the air-fuel ratio was conditioned lean by utilizing an electronic control unit to adjust the injector spray duration. This experiment provides results that there is a potential for mild knocking on the use of alcohol fuel with lean fuel mixture conditions at engine speed 4000 RPM, while at engine speed 6000 RPM and 8000 RPM the use of GEM tends to be stable, but in the CCV results the increase in COV (coefficient of variation) value using GEM fuel tends to be more sloping, especially with the addition of more methanol. Emission results from the use of GEM produce top emission CO2 value obtained by the E5M15 mixture at λ=1.2 and an engine speed of 8000 RPM, with a value of 13.75% and then peak CO2 emissions at a value of λ = 1.2 whereas in the use of pure gasoline peak CO2 is at a value of λ = 1.1.

Visualisation Testing of the Vertex Angle of the Spray Formed by Injected Diesel–Ethanol Fuel Blends

The internal combustion engine continues to be the main source of power in various modes of transport and industrial machines. This is due to its numerous advantages, such as easy adaptability, high efficiency, reliability and low fuel consumption. Despite these beneficial qualities of internal combustion engines, growing concerns are related to their negative environmental impacts. As a result, environmental protection has become a major factor determining advancements in the automotive industry in recent years, with the search for alternative fuels being one of the priorities in research and development activities. Among these, fuels of plant origin, mainly alcohols, are attracting a lot of attention due to their high oxygen content (around 35%). These fuels differ from diesel oil, for instance, in kinematic viscosity and density, which can affect the formation of the fuel spray and, consequently, the proper functioning of the compression–ignition engine, as well as the performance and purity of the exhaust gases emitted into the environment. The process of spray formation in direct injection compression–ignition engines is extremely complicated and requires detailed analysis of the fast-changing variables. This explains the need for using complicated research equipment enabling visualisation tests and making it possible to gain a more accurate understanding of the processes that take place. The present article aims to present the methodology for alternative fuel visualisation tests. To achieve this purpose, sprays formed by diesel–ethanol blends were recorded. A visualisation chamber and a high-speed camera were used for this purpose. The acquired video provided the material for the analysis of the changes in the vertex angle of the spray formed by the fuel blends. The test was carried out under reproducible conditions in line with the test methodology. The shape of the fuel spray is impacted by an increase in the proportional content of ethanol in the diesel and dodecanol blend. Based on the present findings, it is possible to note that the values of the vertex angle in the spray produced by the diesel–ethanol blend with the addition of dodecanol are most similar to those produced by diesel oil at an injection pressure of 100 MPa. The proposed methodology enables an analysis of the injection process based on the spray macrostructure parameters, and it can be applied in the testing of alternative fuels.

PtNiRu/SnO2 Nanoframes as Anodic Catalyst for Direct Ethanol Fuel Cells

PtNiRu/SnO₂ Nanoframes as Anodic Catalyst for Direct Ethanol Fuel Cells

Power generation characteristics and optimum alcohol concentration in bio-direct alcohol fuel cell using chitin family electrolyte

Direct alcohol fuel cells (DAFCs) have the potential to become the next-generation portable energy device. However, the development of DAFC requires the explore new electrolytes without fuel crossover. In this study, DAFC with bio-electrolyte have been fabricated and their characteristics have been investigated. Ethanol impermeability measurements revealed that the crossover of ethanol in the chitin and chitosan electrolytes is extremely low. This result indicates that the chitin family electrolyte has the potential of DEFC electrolytes. Furthermore, DAFCs using the chitin electrolyte have been investigated for various alcohol fuels (methanol, ethanol, 1-propanol, and 1-butanol fuels), and the optimum fuel concentrations to achieve the maximum power density in these DAFCs have been determined. In addition, these results and viscosity measurements clarify the optimum alcohol fuel concentration can be obtained by adding the water molecules required for the proton generating reaction to the water molecules required to stabilize alcohol in water.

Innovation trends and evolutionary paths of green fuel technologies in maritime field: A global patent review

As global environmental issues become increasingly prominent, the maritime industry faces an urgent imperative to curtail carbon emissions and mitigate environmental impact. Green marine alternative fuels are actively addressing these challenges. Global patent data are collected, and four sub-technologies of green fuel technologies in the maritime field are extracted based on Natural Language Processing. To evaluate the innovation trends and evolutionary paths of these technologies, the Main Path Analysis is employed to identify the evolution path of technologies and the evolution situation of major innovative entities, while the Social Network Analysis was used to present the results visually. These four sub-technologies (Hydrogen & Fuel Cell, Methanol & Ethanol, Ammonia, and LNG & LPG) have occupied the mainstream of fuel technology in maritime over the past five years, with 34.6% of patents, 38.3% of patent citations, and 93.9% of technological influence, accounting for 27.4%, 20.5%, 16.7% and 44.3%, respectively. Ammonia, and Hydrogen & Fuel Cell are springing up like mushrooms after rain, while the development of LNG & LPG, Methanol & Ethanol is relatively mature. Each of these technologies showcases distinct developmental paradigms. We elaborated on developmental paradigms and future research priorities of each technology in the conclusion. In addition, new technological opportunities are also created through the cross-fertilization of technologies. In particular, integrated systems for hydrogen production, storage, and combustion on LNG ships, and maritime hybrid power systems driven by ammonia and hydrogen have opened a new window for the green development of maritime fuels.

Comprehensive Evaluation of Fuel Ethanol Production from Poplar Wood Fermentation and its Coupled Pathway with Lignin Gasification Based on Energy-Environment-Economy

Comprehensive Evaluation of Fuel Ethanol Production from Poplar Wood Fermentation and its Coupled Pathway with Lignin Gasification Based on Energy-Environment-Economy

Periodic on-off operations of the self-cycling ethanol fermentation process: Stability analysis and optimal operation strategies

Fuel ethanol is highlighted for being renewable and carbon neutral, but a multi-scale challenge exists that hampers its role as a future energy substitute, and with the breakthrough of cellulose pretreatment and enzyme hydrolysis technology, fermentation itself has become one of the main limiting factors for process enhancement. To tackle the problem, this paper studies periodic operation strategies to improve process performance and avoid possible instabilities. Firstly, superiority by periodic operation over the corresponding steady-state operation is verified. Then, to settle the problem of possible instabilities under impulsive control, stability of state-impulsive control is conducted and for the studied case, any self-cycling fermentation starts from batch mode with 50 % discharge-and-refill portion exhibits superior repeatability property, which allows continuous fermentation to operate under very slow overall dilution rate to cope with the extreme slow fermentation rate. Finally, on-off operation problem is formulated that is governed by a multidimensional nonlinear system, affine to the manipulated variable that is under the isoperimetric constraint; with the use of Pontryagin maximum principle, the optimal synthesis of the optimal strategies under integral constraint is computed out, and a practically plausible on-off operation strategy for ethanol fermentation is formulated with guaranteed periodic stability and optimality.

Controlling the Electrode Morphology and Surface Energy to Make Ethanol Fuel Cells Based on Pd-Assisted Etched Porous Silicon

Controlling the Electrode Morphology and Surface Energy to Make Ethanol Fuel Cells Based on Pd-Assisted Etched Porous Silicon

Operational mechanism of valved-pulsejet engines

The study investigates twelve configurations of the self-aspirated valved pulsejet, focusing on its operational mechanism. It begins by characterizing the engine's acoustic field with varied boundary conditions, revealing an extended effective acoustic length beyond the combustion chamber and tailpipe sections when the valve is open. Radial and lateral velocity fluctuations are hypothesized as causes for vortex structure generation. Analysis of reacting pulsejets using gasoline and ethanol fuels shows that the operating frequencies are unaffected by fuel type, with geometric arrangement as the primary frequency factor. Fluctuations in dynamic pressure, microphone readings, and thrust characterize engine stability, impacted by low-frequency modes and higher harmonics. Tailpipe length emerges as the key geometric factor for performance enhancement with the medium size being the optimal option. Pressure field analysis demonstrates shock wave generation during ignition, serving as an excitation mechanism. Notably, different configurations with varied operating frequencies can yield equivalent thrust, indicating that thrust production is not solely dependent on pressure rise during combustion, despite similar pressure rise observed across most cases.

Methanol compared to other fuels for on-board hydrogen production in thermally balanced membrane reactors with internal recycle

New processes for hydrogen production from various sources are required, which will enable decentralized hydrogen utilization. Hydrogen is a challenging energy carrier due to its low volumetric energy density, requiring compression or liquefaction, which are costly steps, reducing the overall energy transformation cycle efficiency. Thus, a hydrogen supply route based on distributed on-demand production is more attractive compared to the traditional centralized production route. In this work we analyze the use of methanol as a hydrogen carrier to be converted to hydrogen in a conceptual autothermal scaled-down system for on-board pure hydrogen production. This system integrates two concentric reactors, membrane separation and heat exchange. The required heat is supplied by catalytic combustion of the reforming effluents which are recycled internally. The temperature profile is controlled by distribution of the combustion feed. A validated mathematical model shows that the thermal efficiency of the hydrogen production process from methanol will be much higher (e.g. 45 % vs 15 % in one case, 60 % vs 30 % in another case) compared to the efficiency obtained when feeding other fuels (methane, ethanol or glycerol). In all cases full conversion of the fuel is obtained. The reason for such a significant intensification is the lack of methane formation in the reforming reactor. This leads to higher driving force for hydrogen transport through the membranes and enables lower operating temperatures, reducing heat losses to the surroundings (which are the main source for efficiency loss). The lack of methane formation is due to the Cu-based catalyst used for methanol reforming, as opposed to the Ni-based catalyst used for reforming of other fuels.