Ethanol Gasoline Research Articles

Quantification of anhydrous ethanol and detection of adulterants in commercial Brazilian gasoline by Raman spectroscopy

Raman spectroscopy can be used to evaluate the quality of fuels in a remote, rapid, and nondestructive manner without the need for reagents. In this study, Raman was used to quantify anhydrous ethanol in commercial gasoline and to detect peaks due to compounds commonly used for the adulteration of commercial gasoline. Samples of commercial gasoline were collected from fuel stations in the region of Santos, SP, Brazil. Samples of naphtha from the refinery, pure ethanol, and ethanol diluted in distilled water at concentrations close to the range used in the gasoline were also obtained and characterized. Raman spectra were collected using a dispersive Raman spectrometer (830 nm, 2 cm−1 resolution in the 400–1800 cm−1 spectral range). As expected, the spectra of commercial gasoline showed pronounced peaks of naphtha and ethanol. By using the peak intensities of the ethanol diluted in water, the ethanol concentration was found to be in the range of 27% ± 1% in most of the samples; some samples presented ethanol concentrations as high as 28.8%, suggesting adulteration. Some samples presented peaks at 766, 798, and 995 cm−1 with higher intensities, suggesting the presence of an adulterant with organic characteristics, such as solvents with aromatic rings. Raman spectroscopy has been shown to be effective in determining the adulteration of commercial gasoline, which may contribute to rapid quality control of fuels at the point of sale.

Investigation of performance and combustion characteristics of a four-valve supercharged two-stroke DI engine fuelled with gasoline and ethanol

Worldwide emission legislations have promoted the development of more efficient internal combustion engines through engine downsizing and advanced lean-burn combustion concepts. However, these measures if solely employed in the next generation vehicles are still not enough to comply with future CO2 limits, so powertrain hybridisation has been already set up. In this circumstance, internal combustion engines play a less important role in the vehicle’s propulsion system serving mostly as a range extender or extra power supply unit. Power density (kW/dm3) and power per unit mass (kW/kg) are as important as fuel consumption, so not only four-stroke engines may serve to this purpose but also two-stroke engines. Therefore, the present research evaluates the performance and combustion characteristics of a two-stroke cycle engine embedded in the architecture of a contemporary four-stroke supercharged engine, with direct fuel injection, intake and exhaust valves, and a wet sump. Commercial gasoline and anhydrous ethanol (E100) were tested at loads from 0.2 MPa to 1.0 MPa indicated mean effective pressure and speeds varying from 800 rpm to 2400 rpm. The results demonstrated that ethanol increased the overall indicated efficiency by about 10% compared to gasoline, while improving the burning process at very light loads thanks to its higher tolerance to diluted combustion. At higher engine loads the calculated supercharger power consumption largely increased, which reduced the corrected indicated efficiency for both fuels tested. The maximum in-cylinder pressure of 6.5 MPa was obtained using ethanol at 160 Nm/dm3 of torque and 800 rpm. The short time available for air-fuel mixing at high loads and excessive combustion dilution at low loads deteriorated the combustion process. The lowest combustion efficiency of 0.80 was obtained at transitioning regions from spark ignition to spark assisted compression ignition combustion with gasoline. The 50% of mass fraction burned was found closer to top dead centre at several operating conditions due to a largely diluted combustion. Finally, the exhaust gas temperature presented a peculiar behaviour due to a competition between combustion rate and exhaust gas dilution by the intake air. This resulted in an exhaust gas temperature as low as 500 K at full load and 800 rpm, while the maximum gas temperature of 740 K was observed at mid-loads.

Effect of Slag on Restoration Mechanical Characteristics of Ethanol Gasoline–Contaminated Clay

AbstractThis study investigates the effect of slag on the mechanical characteristics of clay contaminated with ethanol gasoline (E10) by performing a series of unconfined compressive strength (UCS)...

The evolving Brazilian automotive-energy infrastructure: Entanglements of national developmentalism, sugar and ethanol production, automobility and gasoline

This paper addresses the dynamic sociotechnical construction of automotive-energy infrastructures, based on the case of ethanol fuel in Brazil in the 20th and early 21st centuries. Energy infrastructure projects are afforded but also constrained by technical and institutional “residues” of previous initiatives and achievements. The notion of “knots” is introduced to explore how sociotechnical entanglements interlinking elements from distinct levels of the societal fabric become stabilized and shape subsequent developments. This extension of the sociotechnical approach is shown to be fruitful to better understand the embedding of ethanol fuel in the process of evolution of the automotive-energy infrastructure in Brazil during the 20th century. This then offers building blocks for analysis and design of energy infrastructures in general.

Comparative assessment of ethanol and isobutanol addition in gasoline on engine performance and exhaust emissions

The depletion of fossil fuels is causing great concern and it is important to search for alternatives. Ethanol and isobutanol are suitable for spark ignition engine due to their favorable physicochemical properties that can be blended with pure gasoline to reduce the dependency on petroleum fuels. Six types of fuel blends consisting of ethanol and isobutanol were mixed with gasoline at different volume rates and were tested on a four-cylinder spark ignition engine by varying the engine speeds and engine torques to evaluate their engine performance and exhaust emissions characteristics. The results indicate that the binary blend of E20 gives an increase in torque, brake power and brake thermal efficiency, while the ternary blend of E10iB10 gives an increase in brake specific fuel consumption, compared to that of pure gasoline. In terms of exhaust emissions, E20 and E10iB10 blend show the lowest carbon monoxide and hydrocarbon emissions, respectively, for both conditions. However, all the fuel blends show higher carbon dioxide emissions as compared to pure gasoline. There are no significant differences in nitrogen oxides emissions for all fuel blends with respect to pure gasoline. However, the fuel blends show higher nitrogen oxides emissions at higher engine speeds and torques.

Predicting Octane Number Using Nuclear Magnetic Resonance Spectroscopy and Artificial Neural Networks

Machine learning algorithms are attracting significant interest for predicting complex chemical phenomenon. In this work, a model to predict research octane number (RON) and motor octane number (MON) of pure hydrocarbons, hydrocarbon-ethanol blends, and gasoline–ethanol blends has been developed using artificial neural networks (ANNs) and molecular parameters from 1H nuclear magnetic resonance (NMR) spectroscopy. RON and MON of 128 pure hydrocarbons, 123 hydrocarbon–ethanol blends of known composition, and 30 FACE (fuels for advanced combustion engines) gasoline–ethanol blends were utilized as a data set to develop the ANN model. The effect of weight percent of seven functional groups including paraffinic CH3 groups, paraffinic CH2 groups, paraffinic CH groups, olefinic −CH═CH2 groups, naphthenic CH–CH2 groups, aromatic C–CH groups, and ethanolic OH groups on RON and MON was studied. The effect of branching (i.e., methyl substitution), denoted by a parameter termed as branching index (BI), and molecular w...

Who did the ethanol tax credit benefit? An event analysis of subsidy incidence

At the end of 2011, the Volumetric Ethanol Excise Tax Credit (VEETC), which had subsidized the blending of ethanol in gasoline, was allowed to expire. During its tenure, the subsidy was the subject of intense scrutiny concerning who benefited from its existence. Using commodity price data, we estimate the subsidy incidence accruing to corn farmers, ethanol producers, gasoline blenders, and gasoline consumers around the time of expiration. Our empirical approach contributes methodologically to the event studies literature by analyzing futures contract prices (as opposed to spot prices) when possible. Ultimately, we find compelling evidence that, at the date of VEETC expiration, ethanol producers captured about 25¢ of the 45¢ subsidy per gallon of ethanol blended. We find suggestive, albeit inconclusive, evidence that a portion of this benefit (about 5¢ per gallon) was passed further upstream from ethanol producers to corn farmers. Most of the remainder seems most likely to have been captured by the blenders themselves. On the petroleum side, we find no evidence that oil refiners captured any part of the subsidy. We also find no evidence that the subsidy was passed downstream to gasoline consumers in the form of lower gasoline prices.

Variability in the primary emissions and secondary gas and particle formation from vehicles using bioethanol mixtures

ABSTRACTBioethanol for use in vehicles is becoming a substantial part of global energy infrastructure because it is renewable and some emissions are reduced. Carbon monoxide (CO) emissions and total hydrocarbons (THC) are reduced, but there is still controversy regarding emissions of nitrogen oxides (NOx), aldehydes, and ethanol; this may be a concern because all these compounds are precursors of ozone and secondary organic aerosol (SOA). The amount of emissions depends on the ethanol content, but it also may depend on the engine quality and ethanol origin. Thus, a photochemical chamber was used to study secondary gas and aerosol formation from two flex-fueled vehicles using different ethanol blends in gasoline. One vehicle and the fuel used were made in the United States, and the others were made in Brazil. Primary emissions of THC, CO, carbon dioxide (CO2), and nonmethane hydrocarbons (NMHC) from both vehicles decreased as the amount of ethanol in gasoline increased. NOx emissions in the U.S. and Brazilian cars decreased with ethanol content. However, emissions of THC, CO, and NOx from the Brazilian car were markedly higher than those from the U.S. car, showing high variability between vehicle technologies. In the Brazilian car, formation of secondary nitrogen dioxide (NO2) and ozone (O3) was lower for higher ethanol content in the fuel. In the U.S. car, NO2 and O3 had a small increase. Secondary particle (particulate matter [PM]) formation in the chamber decreased for both vehicles as the fraction of ethanol in fuel increased, consistent with previous studies. Secondary to primary PM ratios for pure gasoline is 11, also consistent with previous studies. In addition, the time required to form secondary PM is longer for higher ethanol blends. These results indicate that using higher ethanol blends may have a positive impact on air quality.Implications: The use of bioethanol can significantly reduce petroleum use and greenhouse gas emissions worldwide. Given the extent of its use, it is important to understand its effect on urban pollution. There is a controversy on whether there is a reduction or increase in PM emission when using ethanol blends. Primary emissions of THC, CO, CO2, NOx, and NMHC for both cars decreased as the fraction of ethanol in gasoline increased. Using a photochemical chamber, the authors have found a decrease in the formation of secondary particles and the time required to form secondary PM is longer when using higher ethanol blends.

Time domain nuclear magnetic resonance (TD-NMR): A new methodology to quantify adulteration of gasoline

The high consumption of gasoline in the Brazilian highway sector (around 32.1%) makes the fuel adulteration a target, especially due to the content of anhydrous ethanol. The excess of ethanol in gasoline beyond the 27% limit (v/v) that is the maximum content allowed by the Brazilian National Agency of Petroleum, Gas and Biofuels (ANP) can cause premature corrosion in the fuel tank, and problems with ignition and engine performance problems. This work proposes the application of a new methodology, time domain nuclear magnetic resonance (TD-NMR) to detect the adulteration of gasoline with ethanol. The results showed that the commercial gasoline has transverse relaxation time (T2) changing between 2.02 and 2.05s, while the ethanol has T2 equal to 1.6s. Samples adulterated with percentage of ethanol between 5% and 50% (v/v) showed T2 ranges between 1.70s and 2.05s. The methodology proposed here showed excellent agreement with infrared in the middle region (MIR) and can used to diverse commercial gasoline. Besides, TD-NMR is simple, the measure are rapid, non-destructiveness and data are easy to be interpreted.

Study of Corrosion Effects of Oxidized Ethanol–Gasoline Blends on Metallic Materials

Bioethanol added into gasolines significantly changes the physical and chemical properties of the resulting fuels and can have a considerable influence on their overall thermo-oxidative stability. During fuel oxidation, different oxidation products such as water, acidic substances, and peroxides are formed and these can have corrosive effects on metallic construction materials of the storage and transportation equipment, engines, and fuel lines of automobiles, etc. In this work, we tested the laboratory prepared ethanol–gasoline blends (EGBs) E10, E25, E40, E60, and E85, which were artificially oxidized depending on their induction period. The oxidized fuels were used to study their corrosion aggressiveness after their thermal load in the presence of oxygen or after the expiry of their shelf life. The corrosion properties of these fuels were tested on steel, copper, aluminum, and brass using electrochemical methods such as electrochemical impedance spectroscopy and Tafel curve analysis. For comparison, st...

From actual ethanol contents in gasoline to mid-blends and E-85 in conventional technology vehicles. Emission control issues and consequences

The study investigated the combustion and emissions of gasoline engines using four ethanol–gasoline blends ranging from 10 to 85 volume percent ethanol, and an E0 control Performance were compared in single cylinder engine and tested in a chassis dynamometer using two Tier I vehicles. The octane sensitivity of the fuels increases with the addition of ethanol from 7.8 for a non-oxygenated fuel to 23 for the 85% ethanol blend. Fuel sensitivity have a direct relationship with the latent heat of vaporization, because charge cooling is one of the way alcohols increases Research Octane Number. For the primary gaseous compounds, an increase in total hydrocarbon emissions and a decrease in aromatic BTEX compounds was detected as the amount of ethanol in the fuel increased. Both vehicles operated without engine fault code display except when the E-85 was used. The engine could be started stably with E10, E20, and E45. However, for E85 the engine idling became unstable because the air–fuel mixture was too lean making impossible the reduction reactions necessary for NOx emission control in the catalytic converter.

Exhaust noise, performance and emission characteristics of spark ignition engine fuelled with pure gasoline and hydrous ethanol gasoline blends

The exhaust noise, performance and emission characteristics of a gasoline engine fuelled by hydrous ethanol gasoline with 10%, 20% hydrous ethanol by volume (E10W and E20W) and pure gasoline (E0) were experimentally investigated. The tests were performed at full load and different engine speeds varying from 1500 rpm to 5000 rpm. The results showed that compared with E0, E10W and E20W had much lower exhaust noise at low engine speeds. With the increase of engine speed, E0 showed an advantage in low exhaust noise. However, engine fuelled with three fuels displayed comparable noise emissions at high speed. In addition, better thermal efficiency, significantly decreased CO and HC emissions were achieved by hydrous ethanol gasoline at all tested operating conditions. However, significant NOx emission and slight BSFC were observed for E10W and E20W. Compared with E20W, E10W showed decreased BSFC, HC and NOx emissions with the increase of engine speed, while CO emission was only slightly increased. Hydrous ethanol gasoline was capable of realizing comparable torque and power with E0 at all operating conditions. From the results above, hydrous ethanol gasoline could be considered as a promising alternative for SI engine. What's more, E10W exhibits enhanced performance.

Lean Burn Performance of a Spark Ignition Engine with an Ethanol–Gasoline Dual Injection System

A spark ignition (SI) engine with an ethanol direct injection (EDI) and gasoline port injection (GPI) system has been studied quite recently. In order to investigate its application, experiments were carried out on a single-cylinder 250 cm3 short stroke motorcycle SI engine, which is supplied with the ethanol–gasoline dual injection system. Experimental findings have revealed that EDI helped increase the lean combustion limit owing to the combination effects of the dual injection and ethanol fuel. At the identical engine speed and load, the lean burn limit in the dual injection model was, on average, 0.2 times higher than that in the corresponding single GPI model. Increasing ethanol energy ratio (EER) gave rise to the increase in the lean burn limit; nevertheless, the increase rate began reducing when the EER was above 48% and 42% at 4000 and 3500 rpm, correspondingly. Subsequently, late ethanol direct injection (LEDI), following the intake valve closing slightly extended the lean burn limit, probably, o...

Carbon footprint and fossil energy consumption of bio-ethanol fuel production from Arundo donax L. crops on marginal lands of Southern Italy

A cradle-to-wheel life cycle analysis evaluated the greenhouse gas (GHG) contribution and fossil energy consumption (FEC) of bio-ethanol (EtOH) from dedicated crops on marginal lands in Campania Region (Southern Italy). The analysis processed experimental agronomic data of giant reed cultivated on hilly areas at high erosion risk and industrial data of feedstock conversion to EtOH, through second generation innovative technologies. Two ethanol–gasoline mixes (E10 and E85) were considered and compared with gasoline vehicle (GV).The E10 GHG and FEC profiles were driven by the gasoline input in the blend and the linked CO2 tailpipe emissions. The EtOH supply chain, especially the crop phase, was the major contributor to E85 impacts. The higher amount of biogenic C in E85 determined a marked reduction over GV of both GHG emissions (−60%) and FEC (−65%). The soil carbon storage would save 25 g CO2 eq per MJ; however, the issue is controversial due to the spatial and temporal variability of the process. Based on land availability, E85 contribution to renewables in the regional transport sector would amount to 4% and the blend wall would be far from saturation. A possible mismatch between future flexi-fuel vehicles density and E85 availability should be considered.

Performance Analysis of an Internal Combustion Engine Using Butanol as an additive in Ethanol Gasoline Blended Fuel

Performance Analysis of an Internal Combustion Engine Using Butanol as an additive in Ethanol Gasoline Blended Fuel

Comparative analysis of the Performance and Emission Characteristics of ethanol-butanol-gasoline blends

Global warming and energy security being the global problems have shifted the focus of researchers on the renewable sources of energy which could replace petroleum products partially or as a whole. Ethanol and butanol are renewable sources of energy which can be produced through fermentation of biomass. A lot of research has already been done to develop suitable ethanol-gasoline blends. In contrast very little literature available on the butanol-gasoline blends. This research focuses on the comparison of ethanol-gasoline fuels with butanol-gasoline fuels with regard to the emission and performance in an SI engine. Experiments were conducted on a variable compression ratio SI engine at 1600 rpm and compression ratio 8. The experiments involved the measurement of carbon monoxide, carbon dioxide, oxides of nitrogen and unburned hydrocarbons emission and among performance parameters brake specific fuel consumption and brake thermal efficiency were recorded at three loads of 2.5kgs (25%), 5kgs (50%) and 7.5kgs (75%). Results show that ethanol and butanol content in gasoline have decreased brake specific fuel consumption, carbon monoxide and unburned hydrocarbon emissions while the brake thermal efficiency and oxides of nitrogen are increased. Results indicate thatbutanol-gasoline blends have improved brake specific fuel consumption, carbon monoxide emissions in an SI engine as compared to ethanol-gasoline blends. The carbon dioxide emissions and brake thermal efficiencies are comparable for ethanol-gasoline blends and butanol-gasoline blends. The butanol content has a more adverse effect on emissions of oxides of nitrogen than ethanol.

Chromogenic Photonic Crystal Sensors Enabled by Multistimuli-Responsive Shape Memory Polymers.

Here novel chromogenic photonic crystal sensors based on smart shape memory polymers (SMPs) comprising polyester/polyether-based urethane acrylates blended with tripropylene glycol diacrylate are reported, which exhibit nontraditional all-room-temperature shape memory (SM) effects. Stepwise recovery of the collapsed macropores with 350 nm diameter created by a "cold" programming process leads to easily perceived color changes that can be correlated with the concentrations of swelling analytes in complex, multicomponent nonswelling mixtures. High sensitivity (as low as 10 ppm) and unprecedented measurement range (from 10 ppm to 30 vol%) for analyzing ethanol in octane and gasoline have been demonstrated by leveraging colorimetric sensing in both liquid and gas phases. Proof-of-concept tests for specifically detecting ethanol in consumer medical and healthcare products have also been demonstrated. These sensors are inexpensive, reusable, durable, and readily deployable with mobile platforms for quantitative analysis. Additionally, theoretical modeling of solvent diffusion in macroporous SMPs provides fundamental insights into the mechanisms of nanoscopic SM recovery, which is a topic that has received little examination. These novel sensors are of great technological importance in a wide spectrum of applications ranging from environmental monitoring and workplace hazard identification to threat detection and process/product control in chemical, petroleum, and pharmaceutical industries.

The Effect of Using Ethanol-Gasoline Blends on the Mechanical, Energy and Environmental Performance of In-Use Vehicles

The use of ethanol in gasoline has become a worldwide tendency as an alternative to reduce net CO2 emissions to the atmosphere, increasing gasoline octane rating and reducing dependence on petroleum products. However, recently environmental authorities in large urban centers have expressed their concerns on the true effect of using ethanol blends of up to 20% v/v in in-use vehicles without any modification in the setup of the engine control unit (ECU), and on the variations of these effects along the years of operation of these vehicles. Their main concern is the potential increase in the emissions of volatile organic compounds with high ozone formation potential. To address these concerns, we developed analytical and experimental work testing engines under steady-conditions. We also tested carbureted and fuel-injected vehicles every 10,000 km during their first 100,000 km of operation. We measured the effect of using ethanol-gasoline blends on the power and torque generated, the fuel consumption and CO2, CO, NOx and unburned hydrocarbon emissions, including volatile organic compounds (VOCs) such as acetaldehyde, formaldehyde, benzene and 1,3-butadiene which are considered important ozone precursors. The obtained results showed statistically no significant differences in these variables when vehicles operate with a blend of 20% v/v ethanol and 80% v/v gasoline (E20) instead of gasoline. Those results remained unchanged during the first 100,000 km of operation of the vehicles. We also observed that when the vehicles operated with E20 at high engine loads, they showed a tendency to operate with greater values of λ (ratio of the actual air-fuel ratio to the stoichiometric air-fuel ratio) when compared to their operation with gasoline. According to the Eco-Indicator-99, these results represent a minor reduction (<1.3%) on the impact to human health, and on the deterioration of the ecosystem. However, it implies a 12.9% deterioration of the natural resources. Thermal equilibrium analysis, at the tailpipe conditions (~100 °C), showed that ethane, formaldehyde, ethylene and ethanol are the most relevant VOCs in terms of the amount of mass emitted. The use of ethanol in the gasoline reduced 20–40% of those emissions. These reductions implied an average reduction of 17% in the ozone formation potential.

Measuring the Regional Availability of Forest Biomass for Biofuels and the Potential of GHG Reduction

Forest biomass is an important resource for producing bioenergy and reducing greenhouse gas (GHG) emissions. The State of Michigan in the United States (U.S.) is one region recognized for its high potential of supplying forest biomass; however, the long-term availability of timber harvests and the associated harvest residues from this area has not been fully explored. In this study time trend analyses was employed for long term timber assessment and developed mathematical models for harvest residue estimation, as well as the implications of use for ethanol. The GHG savings potential of ethanol over gasoline was also modeled. The methods were applied in Michigan under scenarios of different harvest solutions, harvest types, transportation distances, conversion technologies, and higher heating values over a 50-year period. Our results indicate that the study region has the potential to supply 0.75–1.4 Megatonnes (Mt) dry timber annually and less than 0.05 Mt of dry residue produced from these harvests. This amount of forest biomass could generate 0.15–1.01 Mt of ethanol, which contains 0.68–17.32 GJ of energy. The substitution of ethanol for gasoline as transportation fuel has potential to reduce emissions by 0.043–1.09 Mt CO2eq annually. The developed method is generalizable in other similar regions of different countries for bioenergy related analyses.

Effect of petroleum product prices on Thailand's economic growth

Thailand has long been familiar with price control for petroleum products of economic or social importance. This paper applies the model of Garen et al. (2011) to investigate whether increases in petroleum product prices can reduce real gross domestic product (GDP). Time series analysis of data for the 24 quarters from 2009 to 2014 is used to determine real GDP. Two models use an autoregressive conditional heteroskedasticity process with regard to GARCH(1, 1) and EGARCH, and employ lagged variables to incorporate feedback over time. Price increases for both gasoline with 85% ethanol (E85) and unleaded regular gasoline with research octane number of 91 (UGR91) appear to have a positive effect on real GDP. This might be a result of government subsidies and taxes, including the effect of oil companies' income on real GDP. Contrastingly, low sulphur diesel (LSD) price increases appear to have a negative effect on real GDP.