Records with Keyword: Ethanol
Showing records 1 to 25 of 60. [First] Page: 1 2 3 Last
Stability and Performance Analysis of Bioethanol Production with Delay and Growth Inhibition in a Continuous Bioreactor with Recycle
Rubayyi T. Alqahtani, Samir Kumar Bhowmik, Abdelhamid Ajbar, Mourad Boumaza
March 28, 2023 (v1)
Keywords: bioreactor, continuous, delay, Ethanol, model, performance, Saccharomyces bayanus, stability
This paper proposes and analyzes a mathematical model for the production of bioethanol in a continuous bioreactor with recycling. The kinetics correspond to the use of Saccharomyces bayanus for the fermentation of sugars found in wastewater from soft drinks. The proposed model considers product growth latency, which was experimentally found in batch studies of ethanol production. Furthermore, the inhibition effect of ethanol is expressed by a modified version of the classical Andrew’s model for substrate inhibition. The proposed model consists of only three ordinary differential equations containing a minimal number of operating parameters, which include the bioreactor residence time, glucose feed concentration, recycle ratio and the fraction of biomass removed from the reactor by the flow. The positivity and the boundedness of solutions of the model were confirmed under reasonable restrictions of parameters. The stability analysis showed that there is a value of residence time at whic... [more]
Effects of Diethyl Ether Introduction in Emissions and Performance of a Diesel Engine Fueled with Biodiesel-Ethanol Blends
Márcio Carvalho, Felipe Torres, Vitor Ferreira, Júlio Silva, Jorge Martins, Ednildo Torres
March 28, 2023 (v1)
Keywords: Biodiesel, Biofuels, diesel engines, diethyl ether, emissions, Ethanol
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... [more]
Biodiesel Production by Lipase-Catalyzed in Situ Transesterification of Rapeseed Oil Containing a High Free Fatty Acid Content with Ethanol in Diesel Fuel Media
Migle Santaraite, Egle Sendzikiene, Violeta Makareviciene, Kiril Kazancev
March 27, 2023 (v1)
Keywords: biodiesel, Ethanol, in situ transesterification, lipase, mineral diesel, rapeseed oil
In this study, low-quality rapeseed was used as a raw material for biodiesel fuel production. The application of such seeds with an enzyme catalyst is a green approach to producing renewable biodiesel fuel. During the in situ transesterification process, mineral diesel was selected as an extraction solvent for the simultaneous extraction and transesterification of rapeseed oil (RO). This allowed, at the end of the process, for the production of a mixture of mineral diesel and biodiesel fuel. Energy is saved using this process, as the need to extract the oil separately is eliminated and extraction and transesterification take place together in the in situ process. In this study, 11 different lipases were analyzed from which to select the most effective biocatalyst according to the chosen experimental conditions. The most suitable lipase for in situ transesterification was Lipozyme TL IM (Thermomyces lanuginosus). The impact of the temperature and duration of the reaction was investigate... [more]
Ethanol Production from High Solid Loading of Rice Straw by Simultaneous Saccharification and Fermentation in a Non-Conventional Reactor
Inês C. Roberto, Rafael C. A. Castro, João Paulo A. Silva, Solange I. Mussatto
March 24, 2023 (v1)
Keywords: Ethanol, Kluyveromyces marxianus, rice straw, simultaneous saccharification and fermentation, vertical ball mill reactor
Simultaneous saccharification and fermentation (SSF) at high solid loading is a potential approach to improve the economic feasibility of cellulosic ethanol. In this study, SSF using high loading of rice straw was assessed using a vertical ball mill reactor. First, the conditions of temperature and number of glass spheres were optimized at 8% (w/v) initial solids (41.5 °C, 18 spheres). Then, assays were carried out at higher solid loadings (16% and 24% w/v). At 8% or 16% solids, the fermentation efficiency was similar (ηF~75%), but the ethanol volumetric productivity (QP) reduced from 1.50 to 1.14 g/L.h. By increasing the solids to 24%, the process was strongly affected (ηF = 40% and QP = 0.7 g/L.h). To overcome this drawback, three different feeding profiles of 24% pre-treated rice straw were investigated. Gradual feeding of the substrate (initial load of 16% with additions of 4% at 10 and 24 h) and an inoculum level of 3 g/L resulted in a high ethanol titer (52.3 g/L) with QP of 1.1... [more]
Classifying the Level of Energy-Environmental Efficiency Rating of Brazilian Ethanol
Nilsa Duarte da Silva Lima, Irenilza de Alencar Nääs, João Gilberto Mendes dos Reis, Raquel Baracat Tosi Rodrigues da Silva
March 24, 2023 (v1)
Subject: Energy Policy
Keywords: biofuel policy, data mining, efficiency rating, Ethanol
The present study aimed to assess and classify energy-environmental efficiency levels to reduce greenhouse gas emissions in the production, commercialization, and use of biofuels certified by the Brazilian National Biofuel Policy (RenovaBio). The parameters of the level of energy-environmental efficiency were standardized and categorized according to the Energy-Environmental Efficiency Rating (E-EER). The rating scale varied between lower efficiency (D) and high efficiency + (highest efficiency A+). The classification method with the J48 decision tree and naive Bayes algorithms was used to predict the models. The classification of the E-EER scores using a decision tree using the J48 algorithm and Bayesian classifiers using the naive Bayes algorithm produced decision tree models efficient at estimating the efficiency level of Brazilian ethanol producers and importers certified by the RenovaBio. The rules generated by the models can assess the level classes (efficiency scores) according... [more]
Lignocellulosic Ethanol in a Greenhouse Gas Emission Reduction Obligation System—A Case Study of Swedish Sawdust Based-Ethanol Production
Sylvia Haus, Lovisa Björnsson, Pål Börjesson
March 23, 2023 (v1)
Subject: Environment
Keywords: economic performance, Ethanol, GHG emissions, life cycle assessment, lignocellulosic biomass, political incentives
A greenhouse gas (GHG) emission reduction obligation system has been implemented in the Swedish road transport sector to promote the use of biofuels. For transportation fuel suppliers to fulfil this obligation, the volume of biofuel required decreases with decreasing life cycle GHG emission for the biofuel, linking lower GHG emission to higher economic value. The aim of this study was to investigate how the economic competitiveness of a Swedish emerging lignocellulosic-based ethanol production system would be influenced by the reduction obligation. The life cycle GHG emission for sawdust-based ethanol was calculated by applying the method advocated in the EU Renewable Energy Directive (RED II). The saving in GHG emissions, compared with fossil liquid transportation fuels, was 93% for a potential commercial production system in southern Sweden. This, in turn, will increase the competitiveness of sawdust-based ethanol compared to the mainly crop-based ethanol currently used in the Swedis... [more]
Ammonia/Ethanol Mixture for Adsorption Refrigeration
Mauro Luberti, Chiara Di Santis, Giulio Santori
March 23, 2023 (v1)
Keywords: adsorption refrigeration, adsorption thermodynamics, ammonia, chiller, Ethanol, heat pump, ideal adsorbed solution theory, multicomponent potential theory
Adsorption refrigeration has become an attractive technology due to the capability to exploit low-grade thermal energy for cooling power generation and the use of environmentally friendly refrigerants. Traditionally, these systems work with pure fluids such as water, ethanol, methanol, and ammonia. Nevertheless, the operating conditions make their commercialization still unfeasible, especially owing to safety and cost issues as a consequence of the working pressures, which are higher or lower than 1 atm. The present work represents the first thermodynamic insight in the use of mixtures for adsorption refrigeration and aims to assess the performance of a binary system of ammonia and ethanol. According to the Gibbs’ phase rule, the addition of a component introduces an additional degree of freedom, which allows to adjust the pressure of the system varying the composition of the mixture. The refrigeration process was simulated with isothermal- isochoric flash calculations to solve the pha... [more]
A Molecular Dynamics Study of the Generation of Ethanol for Insulating Paper Pyrolysis
Yiyi Zhang, Yi Li, Shizuo Li, Hanbo Zheng, Jiefeng Liu
March 22, 2023 (v1)
Keywords: cellobiose, Ethanol, insulating paper, molecular dynamics, pyrolysis, ReaxFF
Cellulosic insulation paper is usually used in oil-immersed transformer insulation systems. In this study, the molecular dynamics method based on reaction force field (ReaxFF) was used to simulate the pyrolysis process of a cellobiose molecular model. Through a series of ReaxFF- Molecular Dynamics (MD) simulations, the generation path of ethanol at the atomic level was studied. Because the molecular system has hydrogen bonding, force-bias Monte Carlo (fbMC) is mixed into ReaxFF to reduce the cost of calculation by reducing the sampled data. In order to ensure the reliability of the simulation, a model composed of 20 cellobioses and a model composed of 40 cellobioses were respectively established for repeated simulation in the range of 500−3000 K. The results show that insulating paper produced ethanol at extreme thermal fault, and the intermediate product of vinyl alcohol is the key to the aging process. It is also basically consistent with others’ previous experiment results. So it ca... [more]
Assessment of the Effect of Nitrogen Concentration on Fermentation and Selection of a Highly Competitive Saccharomyces cerevisiae Strain for Efficient Ethanol Production
Patricia Portero Barahona, Jesús Martín-Gil, Pablo Martín-Ramos, Ana Briones Pérez, Enrique Javier Carvajal Barriga
March 22, 2023 (v1)
Keywords: Ethanol, Fermentation, nitrogen, Saccharomyces cerevisiae
The optimum nitrogen concentration for media supplementation and strain dominance are aspects of key importance to the industrial production of ethanol with a view to reducing costs and increasing yields. In this work, these two factors were investigated for four ethanologenic Saccharomyces cerevisiae strains (CLQCA-INT-001, CLQCA-INT-005, CLQCA-10-099, and UCLM 325), selected from the screening of 150 isolates, mostly from Ecuadorian yeast biodiversity. The effect of nitrogen concentration was assessed in terms of cellular growth, glucose consumption and ethanol production, and the yeast strains’ dominance was evaluated in continuous co-fermentation with cellular recycling by mitochondrial DNA analyses. Among the four selected yeast strains under study, CLQCA-INT-005 presented the highest glucose consumption at a nitrogen supplement concentration as low as 0.4 g·L−1, attaining an ethanol yield of up to 96.72% in 24 h. The same yeast strain was found to be highly competitive, showing a... [more]
Exploring the Introduction of Plug-In Hybrid Flex-Fuel Vehicles in Ecuador
Danilo Arcentales, Carla Silva
March 21, 2023 (v1)
Subject: Environment
Keywords: Ethanol, final energy, new bus technology, NH3, NOx, PM2.5
In Europe, diesel combustion is being banned due to the NOx and PM2.5 emissions impact on air quality. The bus sector is being electrified and is increasing its use of alternative fuels, such as natural gas (in spark ignition engines) and bioethanol (in compression ignition engines), to reduce such harmful emissions. Even if a diesel bus is equipped with selective catalytic reduction (SCR), its NOx emissions are reduced its but produces more NH3 emissions that are PM2.5 precursors. In developing countries, the air quality is still barely monitored, however, the air quality issue is well known and is being addressed. Moreover, the Ecuadorian sugar cane industry is seeking ways to increase its ethanol production. This is the ideal framework to explore a new technology and energy source in developing economies such as Ecuador. This paper explores the impact of the Ecuadorian diesel bus fleet conversion to hybrid compression ignition ethanol (HEV-ED95), hybrid diesel and plug-in hybrid fle... [more]
Diffusion of Ethanol in Supercritical Carbon Dioxide—Investigation of scCO2-Cosolvent Mixtures Used in Pharmaceutical Applications
Cecília I. A. V. Santos, Marisa C. F. Barros, Ana C. F. Ribeiro
March 20, 2023 (v1)
Subject: Materials
Keywords: diffusion coefficients, Ethanol, supercritical CO2, Taylor dispersion
Diffusion coefficients, D, for ethanol in supercritical carbon dioxide (scCO2) were measured in the temperature range 306.15−331.15 K and along the 10.5 MPa isobar, using the Taylor dispersion technique. The obtained diffusivities ranged from 1.49 × 10−8 to 2.98 × 10−8 m2 s−1, an order of magnitude higher than in usual liquids. The dependence of D on temperature and solvent density was examined. Various correlation models based in the hydrodynamic theory were assessed to estimate the diffusion coefficients, with reasonable results obtained for the Wilke−Chang and Lai−Tan models.
Application of Miller Cycle and Net-Zero Fuel(s) to Diesel Engine: Effect on the Performance and NOx Emissions of a Single-Cylinder Engine
Motong Yang, Yaodong Wang
March 20, 2023 (v1)
Keywords: engine performance, Ethanol, Hydrogen, Miller cycle, NOx emission
Diesel engines play a very significant role in the automotive industry, but the total emissions of diesel engines are more than 1.8 times that of petrol engines. It is therefore important for diesel engines to control emissions. Theoretically, the Miller cycle can be used to achieve NOx reductions by changing the effective compression ratio, while it has become increasingly popular in recent years with the increasing maturity of current turbocharging technology. Based on Ricardo WAVE software, this paper analyses the NOx emissions and engine performance of diesel engines by modelling and simulating their operation under different loads with two types of Miller cycles (EIVC and LIVC) at different degrees. Simulation of engines operating under different loads allows a more comprehensive study of the effects of the Miller cycle on the engine, and a specific analysis in the context of the actual engine operating environment. The result is that both versions of the Miller cycle are most eff... [more]
A Study of the Impact of Methanol, Ethanol and the Miller Cycle on a Gasoline Engine
Luke Oxenham, Yaodong Wang
March 10, 2023 (v1)
Keywords: Ethanol, Methanol, miller cycle, petrol engine, turbocharger
This paper focuses on the investigation and optimisation of the Miller cycle, methanol, ethanol and turbocharging when applied to a high-performance gasoline engine. These technologies have been applied both individually and concurrently to test for potential compounding effects. Improvements have been targeted with regards to both emission output and performance. Also assessed is the capability of the engine to operate when exclusively powered by biofuels. This has been carried out numerically using the 1D gas dynamics tool ‘WAVE’, a 1D Navier−Stokes equation solver. These technologies have been implemented within the McLaren M838T 3.8L twin-turbo engine. The Miller cycle early intake valve close (EIVC) improved peak efficiency by 0.17% and increased power output at low and medium loads by 11%. Reductions of 6% for both NOx and CO were also found at rated speed. The biofuels achieved NOx and CO reductions of 60% and 96% respectively, alongside an efficiency increase of 2.5%. Exclusive... [more]
Value Proposition of Different Methods for Utilisation of Sugarcane Wastes
Ihsan Hamawand, Wilton da Silva, Saman Seneweera, Jochen Bundschuh
March 9, 2023 (v1)
Subject: Environment
Keywords: bioenergy, Ethanol, mill mud, sugarcane wastes, utilisation, value proposition
There are four main waste products produced during the harvesting and milling process of sugarcane: cane trash, molasses, bagasse and mill mud−boiler ash mixture. This study investigates the value proposition of different techniques currently not being adopted by the industry in the utilisation of these wastes. The study addresses the technical challenges and the environmental impact associated with these wastes and comes up with some recommendations based on the recent findings in the literature. All the biomass wastes such as bagasse, trash (tops) and trash (leaves) have shown great potential in generating higher revenue by converting them to renewable energy than burning them (wet or dry). However, the energy content in the products from all the utilisation methods is less than the energy content of the raw product. This study has found that the most profitable and challenging choice is producing ethanol or ethanol/biogas from these wastes. The authors recommend conducting more rese... [more]
An Experimental and Kinetic Modelling Study on Laminar Premixed Flame Characteristics of Ethanol/Acetone Mixtures
Yangxun Liu, Weinan Liu, Huihong Liao, Wenhua Zhou, Cangsu Xu
March 8, 2023 (v1)
Keywords: acetone, Ethanol, laminar burning characteristics, skeletal mechanism, spherically expanding flame
Since both ethanol and acetone are the main components in many alternative fuels, research on the burning characteristics of ethanol-acetone blends is important to understand the combustion phenomena of these alternative fuels. In the present study, the burning characteristics of ethanol-acetone fuel blends are investigated at a temperature of 358 K and pressure of 0.1 MPa with equivalence ratios ranging from 0.7 to 1.4. Ethanol at 100% vol., 25% vol. ethanol/75% vol. acetone, 50% vol. ethanol/50% vol. acetone, 75% vol. ethanol/25% vol. acetone, and 100% vol. acetone are studied by the constant volume combustion chamber (CVCC) method. The results show that the laminar burning velocities of the fuel blends are between that of 100% vol. acetone and 100% vol. ethanol. As the ethanol content increases, the laminar burning velocities of the mixed fuels increase. Furthermore, a detailed chemical kinetic mechanism (AramcoMech 3.0) is used for simulating the burning characteristics of the mixt... [more]
Sugar Beet Pulp in the Context of Developing the Concept of Circular Bioeconomy
Michał Ptak, Agnieszka Skowrońska, Hanna Pińkowska, Małgorzata Krzywonos
March 3, 2023 (v1)
Subject: Environment
Keywords: bioeconomy, biogas, bioproduct, circular economy, Ethanol, sugar beet pulp
The primary objective of this paper is to identify the possibilities of using sugar beet pulp as feedstock to produce a variety of added-value products. Such an application of the sugar production byproducts contributes to implementing circular bio-economy, which is a source of many economic, social, and environmental benefits. Specific objectives of this paper are: (1) Presenting the concept and meaning of circular bio-economy. (2) Characterizing properties of the sugar beet pulp from the perspective of using them as feedstock. (3) Determining the volume of production of the sugar beet pulp and the current methods of using them. (4) Determining the methods of obtaining attractive bioproducts and renewable energy from sugar beet pulp. Special attention was given to the amount of sugar beet pulp produced in Polish sugar refineries. Poland is among the European countries in which the volume of produced sugar is especially high. Therefore, the problem of appropriate waste management in th... [more]
Effect of Zinc-Calcium on Xylose Consumption by Mucor circinelloides (MN128960): Xylitol and Ethanol Yield Optimization
Hector M. Fonseca-Peralta, Karen V. Pineda-Hidalgo, Claudia Castro-Martínez, Ignacio Contreras-Andrade
March 2, 2023 (v1)
Keywords: Biofuels, calcium, Ethanol, Fermentation, Mucor circinelloides, Optimization, xylitol, xylose, zinc
Xylose is the second most abundant monomeric sugar on earth. Nevertheless, metabolizing xylose into ethanol is a complex process due to several biochemical reactions. Some microorganisms of the genus Mucor are suitable for this bioprocess. Using metal ions, such as zinc and calcium, allows some fungal species to increase their ethanol yield. In this work, the wild strain Mucor spp. (C1502) was molecularly identified via internal transcribed spacer (ITS) sequencing. Secondly, an optimization using response surface methodology (RSM) with a central composite experimental design (CCD) was carried out. The independent variables (X) were ZnSO4·7H2O (X1, 0.0−1.5 g/L) and CaCl2 (X2, 0.0−2.5 g/L) concentration in the fermentation broth in order to demonstrate the effect of these ions, xylose was used as the only carbon source. The dependent variables (Y) measured were ethanol yield (Y1, g ethanol/g xylose) and xylitol yield (Y2, g xylitol/g xylose). The identified strain, Mucor circinelloides,... [more]
Life Cycle and Exergoenvironmental Analyses of Ethanol: Performance of a Flex-Fuel Spark-Ignition Engine at Wide-Open Throttle Conditions
Eduardo J. C. Cavalcanti, Daniel R. S. da Silva, Monica Carvalho
March 2, 2023 (v1)
Subject: Environment
Keywords: Ethanol, Ethanol, exergoenvironmental analysis, Gasoline, internal combustion engine, life cycle assessment
The growth in the number of vehicles circulating has led to a proportional increase in polluting gas emissions. Bioenergy can be used to help meet these increasing energy demands and mitigate environmental impacts. This work verified the effect of the content of ethanol on the exergy and exergoenvironmental analyses of a spark-ignition engine. Different gasoline−ethanol mixtures were tested along with hydrous ethanol (4.6% water by volume). The thermodynamic data refer to wide-open throttle conditions and variable engine speeds. The life cycle assessment methodology quantified the environmental impacts associated with equipment and fuel using the Eco-indicator 99 method. Pollutants emitted during combustion were measured and included in the environmental assessment (nitrogen oxides, carbon monoxide, and dioxide). Hydrous ethanol at 1500 rpm presented the highest energy efficiency. The effects of the environmental impact rate of pollutant formation and exergy efficiency were significant... [more]
Life Cycle and Exergoenvironmental Analyses of Ethanol: Performance of a Flex-Fuel Spark-Ignition Engine at Wide-Open Throttle Conditions
Eduardo J. C. Cavalcanti, Daniel R. S. da Silva, Monica Carvalho
March 2, 2023 (v1)
Subject: Environment
Keywords: Ethanol, Ethanol, exergoenvironmental analysis, Gasoline, internal combustion engine, life cycle assessment
The growth in the number of vehicles circulating has led to a proportional increase in polluting gas emissions. Bioenergy can be used to help meet these increasing energy demands and mitigate environmental impacts. This work verified the effect of the content of ethanol on the exergy and exergoenvironmental analyses of a spark-ignition engine. Different gasoline−ethanol mixtures were tested along with hydrous ethanol (4.6% water by volume). The thermodynamic data refer to wide-open throttle conditions and variable engine speeds. The life cycle assessment methodology quantified the environmental impacts associated with equipment and fuel using the Eco-indicator 99 method. Pollutants emitted during combustion were measured and included in the environmental assessment (nitrogen oxides, carbon monoxide, and dioxide). Hydrous ethanol at 1500 rpm presented the highest energy efficiency. The effects of the environmental impact rate of pollutant formation and exergy efficiency were significant... [more]
Measurement of Sub-23 nm Particles Emitted from PFI/DI SI Engine Fueled with Oxygenated Fuels: A Comparison between Conventional and Novel Methodologies
Francesco Catapano, Silvana Di Iorio, Agnese Magno, Paolo Sementa, Bianca Maria Vaglieco
March 1, 2023 (v1)
Keywords: advanced HM-DMA, Ethanol, spark ignition engine, sub-23 nm particles
This study focuses on the measurement of sub-23 nm particles emitted from a small DI/PFI spark ignition engine through conventional techniques and innovative systems. Measurements were performed with well-known systems, such as the EEPS coupled to a PMP-compliant sample conditioning device. Moreover, a novel instrument developed within the European project Sureal-23, the advanced HM-DMA, capable of operating with a simplified conditioning setup was used. The engine was fueled with ethanol, both pure and in blend at 30% v/v. The effects of fuel on the particle emissions were analyzed at different operating conditions. The results highlighted that a larger fraction of emissions consists of particles smaller than 23 nm, and their number changes according to the fuel, injection strategy and operating condition. A significant effect of the sampling system conditions was observed reveling the inception of nucleation mode particles or the condensation of the volatiles onto existing particles... [more]
Experimental and Numerical Study on the Effect of Hydrogen Addition on Laminar Burning Velocity of Ethanol−Air Mixtures
Jianxi Zhou, Chenyu Lu, Cangsu Xu, Zitao Yu
March 1, 2023 (v1)
Keywords: Ethanol, Hydrogen, laminar burning velocity, sensitive analysis
To understand the effect of hydrogen addition on the laminar burning velocity (LBV) of ethanol−air mixtures, experiments were conducted in a constant volume combustion chamber with the high-speed schlieren photography technique. The experiments were carried out under the equivalence ratios (ERs) of 0.7−1.4, an initial temperature of 400 K, an initial pressure of 0.1 MPa, and hydrogen fractions of 30% and 90% by volume, respectively. The effects of ER, initial temperature, initial pressure, and hydrogen fractions on the LBV were investigated. Moreover, adiabatic flame temperature (AFT), heat release rate (HRR), flow rate sensitivity analysis, and ROP (rate of production) analysis were also performed. Results showed that LBV increased with increasing hydrogen addition and temperature but decreased with increasing pressure. The hydrogen addition significantly increased the HRR of ethanol−hydrogen−air flames. The sensitivity analysis showed that R5 (O2 + H = O + OH) significantly influence... [more]
Efficient Conversion of Ethanol to Hydrogen in a Hybrid Plasma-Catalytic Reactor
Bogdan Ulejczyk, Paweł Jóźwik, Łukasz Nogal, Michał Młotek, Krzysztof Krawczyk
March 1, 2023 (v1)
Keywords: Ethanol, Hydrogen, reforming
The present work describes highly efficient hydrogen production from ethanol in a plasma-catalytic reactor depending on the discharge power and catalyst bed temperature. Hydrogen production increased as the power increased from 15 to 25 W. A further power increase to 35 W did not increase hydrogen production. The catalyst was already active at a temperature of 250 °C, and its activity increased with increasing temperature to 450 °C. The further temperature increase did not increase the activity of the cobalt catalyst. The most important advantage of using the catalyst was the increased ethanol conversion to CO2 instead of CO production. As a result, the hydrogen yield was very high and reached 4.1 mol(H2)/mol(C2H5OH). This result was obtained with a stoichiometric molar ratio of water to ethanol of 3.
An Experimental and a Kinetic Modelling Study of Ethanol/Acetone/Ethyl Acetate Mixtures
Yangxun Liu, Weinan Liu, Huihong Liao, Hasier Ashan, Wenhua Zhou, Cangsu Xu
March 1, 2023 (v1)
Keywords: acetone, Ethanol, ethyl acetate, laminar burning velocity, mechanism reduction
With the world’s energy resources decreasing, ethanol/acetone/ethyl acetate mixed fuel has the potential as a fossil fuel alternative or oxygenated fuel additive. In this work, the burning characteristics of ethanol/acetone/ethyl acetate mixed fuels including 3 pure fuels, 9 binary fuels, and 7 ternary fuels were studied at a temperature of 358 K, the pressure of 1 bar, and the equivalence ratios of 0.7 to 1.4 in the constant volume combustion chamber (CVCC). The burning velocities of the ternary fuels were compared at ϕ = 0.8, 1.0, and 1.4. The results show that the laminar burning velocities of the mixed fuels are affected by the contents of ethanol, acetone, and ethyl acetate. The Markstein length, Markstein number, and burning flux were also analyzed in this paper. Furthermore, a detailed chemical mechanism comprising 506 species and 2809 reactions was reduced to a skeletal mechanism including 98 species and 642 reactions, using the directed relation graph with error propagation (D... [more]
Emission and Performance Evaluation of a Diesel Engine Using Addition of Ethanol to Diesel/Biodiesel Fuel Blend
Emmanuelle Soares de Carvalho Freitas, Lílian Lefol Nani Guarieiro, Marcus Vinícius Ivo da Silva, Keize Katiane dos Santos Amparo, Bruna Aparecida Souza Machado, Egidio Teixeira de Almeida Guerreiro, José Fernando Carneiro de Jesus, Ednildo Andrade Torres
March 1, 2023 (v1)
Keywords: diesel engine, Ethanol, fuel blends
Many countries have adopted the addition of biodiesel to diesel as a way of inserting renewable content into mineral fuel and making a contribution to the environment. The addition of ethanol to the diesel/biodiesel blend to increase the renewable content of the added fuel blend and reduce the percentage of biodiesel could be a strategysince the demand for biodiesel production is high, and this fuel has a high production cost when compared to ethanol. Thus, this study evaluated the performance and the content of NOx, CO and CO2 exhaust gases from a diesel engine fueled with blends of diesel/biodiesel/ethanol: pure B7, B7E3 (B7 with 3% ethanol) and B7E10 (B7 with 10% ethanol). Emissions of fuel blends were evaluated using the engine speed variation and tested at a speed of 1500 rpm under constant load (185 Nm). Assays were performed at engine speeds of 1000, 1100, 1250, 1500 and 1750 rpm and with loads of 10, 25, 50, 75 and 100% of the maximum torque. Through the performance curves, the... [more]
High Load Compression Ignition of Wet Ethanol Using a Triple Injection Strategy
Brian Gainey, Ziming Yan, John Gandolfo, Benjamin Lawler
February 28, 2023 (v1)
Keywords: advanced compression ignition, biofuel, compression ignition, Ethanol, wet ethanol
Wet ethanol is a biofuel that can be rapidly integrated into the existing transportation sector infrastructure and have an immediate impact on decarbonization. Compared to conventional hydrocarbon fuels, wet ethanol has unique fuel properties (e.g., short carbon chain, oxygenated, high heat of vaporization, no cool-flame reactivity), which can actually improve the efficiency and engine-out emissions of internal combustion engines while decarbonizing. In this work, wet ethanol 80 (80% ethanol, 20% water by mass) was experimentally studied at high loads under boosted conditions in compression ignition to study the tradeoffs in efficiency and emissions based on boosting and injection strategies. Specifically, this work explores the potential of adding a third, mixing-controlled injection at high loads. The results indicate that adding a third, mixing-controlled injection results in combustion stabilization at high loads, where the peak pressure limit of the engine is a constraint that req... [more]
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