Base Gasoline Research Articles

Physical properties of gasoline, isobutanol and ETBE binary blends in comparison with gasoline ethanol blends

The addition of renewable fuels to gasoline, such as bio-alcohols or bio-ethers is required in order to be in compliance with current environmental directives. Nevertheless, they change fuel properties which could affect standards compliance, engine performance and air emissions. This paper studies the impact of ethanol (EtOH), isobutanol (iBtOH) or ethyl tert-butyl ether (ETBE) on the Reid Vapour Pressure (RVP), distillation curves, density and other related gasoline properties, which belong to the group of relevant specifications that affect engine operation. The main conclusion is that the addition of ETBE or iBtOH has important advantages over EtOH in terms of energy density, air/fuel ratio, vapour pressure, renewable content and other effects; it was also found that the addition of ETBE affects equally and linearly the properties of two kinds of base gasolines as compared with other studies.

Evaluation of the time-resolved nanoparticle emissions and the vehicle performance characteristics for a turbocharged gasoline direct-injection vehicle with a metal-foam gasoline particulate filter

The nanoparticle emissions from gasoline direct-injection engines are of concern because of the high particle number concentrations compared with those from a gasoline port fuel injection engine. A gasoline particulate filter is a potential solution for reducing the particulate matter emissions. In this study, a 2.0 l turbocharged gasoline direct-injection vehicle with a metal-foam-type gasoline particulate filter was tested using the New European Driving Cycle and steady vehicle operating conditions. The particle number concentration, the particle-size distribution and the filtration efficiency were determined using a condensation particle counter and a fast response differential mobility spectrometer (DMS500). The particle number emissions (particle numbers per vehicle travelling distance (particles/km)) over the New European Driving Cycle were 1.95 × 1012 particles/km for a base vehicle equipped with a three-way catalytic converter and 5.68 × 1011 particles/km for the additional installation of a gasoline particulate filter on the base gasoline direct-injection vehicle. The filtration efficiency of the particle number and the particulate matter mass reached approximately 71% and 67% respectively. The nucleation-mode particles in the size range less than 23 nm for the gasoline direct-injection vehicle equipped with a three-way catalytic converter were further reduced on installation of a gasoline particulate filter at the downstream position of the three-way catalytic converter. A sharp pressure drop between the gasoline particulate filter of 21.0 mbar was obtained at a vehicle speed of 120 km/h in the New European Driving Cycle. The exhaust gas temperature before the gasoline particulate filter reached around 380–610 °C at steady vehicle speeds of 60–120 km/h. The installation of the gasoline particulate filter has the potential to satisfy the Euro 6c particle number emissions regulations for light-duty gasoline direct-injection vehicles.

The Effects of Methanol Fraction on the Azeotropic Behaviors of Methanol/Gasoline Mixtures

Methanol is regarded as a potential alternative fuel for spark ignition (SI) engine. It is feasible for SI engines to run on methanol/gasoline mixtures. When methanol is mixed with gasoline, the physicochemical properties of the mixtures are changed different from the properties of both methanol and pure gasoline to some extent. This paper focused on the azeotropic behaviors of saturated vapor pressure (ps) and the distillation curves of methanol/gasoline mixtures. And compositions of the distillates were identified and quantified by a gas chromatography—mass spectrometry (GC–MS) under various Td. Experimental results show that the ps and distillation curves of methanol/gasoline mixtures showed strong positive deviation of Raoult’s law. The maximum deviation occurred around the Td of methanol’s boiling point, i.e., 64.5°C. Increasing the heavy hydrocarbon contents in gasoline could draw the Td of methanol/gasoline mixtures back to that of base gasoline. C4–C8 alkanes, olefins, and benzenes were the main components in distillates of gasoline and its methanol mixture. However, the additive with hetero atom of oxygen, methyl tertiary butyl ether (MTBE) was the leading component with the largest mass percentage in all the distillates, while methanol was another leading component in methanol mixture distillates. Methanol co-boiled with all of the gasoline components rather than with some certain ones; even so, pentane, 2-methyl-2-butene and toluene were the three leading azeotropes with the change ratio of over 4% in mass percentage.

Vapor Pressure and Octane Numbers of Ternary Gasoline–Ethanol–ETBE Blends

The objective of this study was to examine key gasoline properties, such as octane rating and volatility of ternary blends with ethanol and ethyl-tert-butyl-ether (ETBE). Ethanol and ETBE were added in various concentrations in specific refinery gasoline pool components, so a total of 30 gasoline-ethanol-ETBE samples were prepared and tested. Vapor pressure and octane numbers [research octane number (RON) and motor octane number (MON)] were determined for the mixtures containing 0.9-5.5% v/v ethanol and 2.0-9.8% v/v ETBE. Ethanol was always considered a valuable component for refinery gasoline pool due to its good antiknock characteristics. However, its azeotropic behavior in gasoline is considered as a drawback for the vapor pressure of the blend. On the other hand, the use of ETBE in gasoline increases the octane number and lowers the vapor pressure, thus allowing refinery blenders to use a higher vapor pressure base gasoline in the final fuel formulation. Experimental results indicated that ethanol concentration up to 5% v/v in the gasoline formulation increased the vapor pressure of the mixture. The addition of both ethanol and ETBE in the base gasoline resulted in ternary mixtures which smoothed the behavior of the vapor pressure while they acted as excellent octane improvers.

A Study on Global Cooperation Strategy in Oil Industry Based on The Game Theory

Light-duty vehicles consume over 21 million barrels of oil per day. Recent studies, however, have predicted the imminent oil age end. In addition, environmental restrictions point to ethanol as strong candidate to replace gasoline. On the other hand, the expected light-duty vehicles' worldwide growth and limited capacity for ethanol production suggest that total substitution of gasoline is not feasible in the short to medium-term. Nonetheless, 30% ethanol to gasoline blend could increase the performance of internal combustion engines, decrease the emission of greenhouse gases and alters the oil reserves depletion rate. In this study the benefits of using ethanol as a complement to base gasoline and its effects on the world’s conventional oil reserves is analyzed. Finally, based on game theory, the transition process to a biomass age could focus on cooperation and compromise strategies in pursuing optimal results for both oil and ethanol industries.

Effect of oxygenates blending with gasoline to improve fuel properties

The purpose of this paper is to study the effect of oxygenate additives into gasoline for the improvement of physicochemical properties of blends. Methyl Tertiary Butyl Ether (MTBE), Methanol, Tertiary butyl alcohol (TBA), and Tertiary amyl alcohol (TAA) blend into unleaded gasoline with various blended rates of 2.5%, 5%, 7.5%, 10%, 15%, and 20%. Physicochemical properties of blends are analyzed by the standard American Society of Testing and Materials (ASTM) methods. Methanol, TBA, and TAA increase density of the mixtures, but MTBE decreases density. The addition of oxygenates lead to a distortion of the base gasoline’s distillation curves. The Reid vapor pressure (RVP) of gasoline is found to increase with the addition of the oxygenated compounds. All oxygenates improve both motor and research octane numbers. Among these four additives, TBA shows the best fuel properties.

Emissions from Ethers and Organic Carbonate Fuel Additives: A Review

This paper is a review of the available literature on the main features of 11 of the most widely adopted oxygenated additives to base gasoline and diesel, focusing particularly on the emissions from the oxygenates considered as additives. The oxygenated additives studied are methyl tert-butyl ether, ethyl tertiary butyl ether, tert-amyl ethyl ether, tertiary amyl methyl ether, isopropyl ether, dimethyl carbonate, dimethoxymethane, dibutyl ether, diglycol methyl ether, diethyl carbonate, and 2-methoxyethyl acetate.

Octane Numbers of Ethanol− and Methanol−Gasoline Blends Estimated from Molar Concentrations

When expressed using volumetric concentrations (as is industry practice), the addition of relatively small amounts of ethanol or methanol (e.g., 10% by volume) to gasoline appears to result in disproportionately large, nonlinear increases in research octane number (RON) and motor octane number (MON). As a result, volumetric “blending octane numbers” are of limited value for estimating the octane number of alcohol−gasoline blends because they vary with alcohol content and base gasoline composition. We show that RON and MON increases with alcohol content are approximately linear when expressed using molar concentrations. Moreover, molar-based blending octane numbers are effectively equal to the octane numbers of the pure alcohols for most base gasolines. A limited dependence on gasoline composition was observed, namely, greater-than-predicted octane numbers for ethanol−gasoline blends with unusually high isoparaffin content. We suggest that octane numbers of methanol−gasoline and ethanol−gasoline blends can be estimated conveniently and more accurately from their molar composition by linear interpolation between the octane numbers of the base gasoline and the pure alcohol.

Analysis of Organometallic Gasoline Additives with the Composition-Explicit Distillation Curve Method

Problems associated with pre-ignition of fuel in a spark-ignition engine have been documented for many years and include poor performance and structural damage in engines. These problems were addressed in the past by adding organometallic additives, such as tetraethyl lead (TEL), to the fuel. While this additive is banned, others are permitted in some jurisdictions. Two such additives are ferrocene (FC) and methylcyclopentadienyl manganese tricarbonyl (MMT). In this paper, we apply the advanced distillation curve approach to the analysis of these two additives (at concentrations of 20 and 40 mg/L) in a typical gasoline. We observe that neither additive affects the volatility of gasoline until the 55% distillate volume fraction. Subsequent to this fraction, we note temperature departures from the base gasoline that progress from 1 to 7 °C for FC and from approximately 1 to 4 °C for MMT. We further note, with the composition-explicit data channel of the advanced distillation curve (ADC), that the additives are not found in the distillate until after the 55% distillate volume fraction and that the concentration in the distillate increases as the distillation proceeds to completion.

Selective Additives for Improvement of Gasoline Octane Number

High octane blend base gasoline stocks are reformulated from 30% LSRN, 45% Reformate and 25% Powerformate on volume basis. ASTM standard and IROX 2000 analysis are performed to test blend stocks sample. Different additive types are used to improve octane number. These additives are tetraethyl lead, methylcyclopentadienyl manganese tricarbonyl; methyl alcohol, ethyl alcohol, iso-propanol, n-butanol, sec-butanol, tertiary butyl alcohol, tert-amyl alcohol, active amyl alcohol, iso-pentyl alcohol, isobutyl carbinol, benzol ,telone, xylene, amino benzene, N-N-dimethyl aniline, dimethyl ketone, and ethyl methyl ketone. Comparison is made between significant individual RON gains measured by standard CFR test-engine. The results indicated that the combined iso-propanol, oxinol (50/50 blend of methanol and TBA), aniline, and xylene with hydrocarbons fraction content in the gasoline base pool is better to ensure high RON. The results showed that a mixture of 20/54/10/16 of blend aniline/ iso-propanol/ oxinol/ xylene respectively, led to an increase in RON of gasoline blend pool from 84.5 to 96 RON, or 11.5% RON gain.

Selective Additives for Improvement of Gasoline Octane Number

High octane blend base gasoline stocks are reformulated from 30% LSRN, 45% Reformate and 25% Powerformate on volume basis. ASTM standard and IROX 2000 analysis are performed to test blend stocks sample. Different additive types are used to improve octane number. These additives are tetraethyl lead, methylcyclopentadienyl manganese tricarbonyl; methyl alcohol, ethyl alcohol, iso-propanol, n-butanol, sec-butanol, tertiary butyl alcohol, tert-amyl alcohol, active amyl alcohol, iso-pentyl alcohol, isobutyl carbinol, benzol ,telone, xylene, amino benzene, N-N-dimethyl aniline, dimethyl ketone, and ethyl methyl ketone. Comparison is made between significant individual RON gains measured by standard CFR test-engine. The results indicated that the combined iso-propanol, oxinol (50/50 blend of methanol and TBA), aniline, and xylene with hydrocarbons fraction content in the gasoline base pool is better to ensure high RON. The results showed that a mixture of 20/54/10/16 of blend aniline/ iso-propanol/ oxinol/ xylene respectively, led to an increase in RON of gasoline blend pool from 84.5 to 96 RON, or 11.5% RON gain.

Vapor Pressures of Alcohol−Gasoline Blends

Reid vapor pressures (RVPs) were determined for alcohol−gasoline blends containing 5−85% by volume of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, i-butanol (2-methyl-1-propanol), and t-butanol (2-methyl-2-propanol). The results are compared to literature data. Most alcohols form near-azeotropic mixtures with hydrocarbons in gasoline that affect the vapor pressure of the blend in a non-ideal manner. In addition, vapor pressures of dual-alcohol blends with gasoline containing a range of ethanol and 1-butanol volume percentages were determined. We demonstrate a simple method to prepare dual-alcohol−gasoline blends with RVPs indistinguishable from that of the base gasoline. It may be advantageous to use alcohols in addition to ethanol in the form of dual- or multi-alcohol blends as these become available in larger scale in the future.

Distillation Curves for Alcohol−Gasoline Blends

Distillation curves are presented for single-alcohol blends in gasoline, containing 5−85% by volume of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, i-butanol (2-methyl-1-propanol), and t-butanol (2-methyl-2-propanol). Most alcohols are shown to form mixtures with gasoline exhibiting near-azeotropic behavior that significantly affect the shape of the distillation curves. The results are compared to literature data available for some alcohols. In addition, distillation curves for a variety of dual-alcohol blends are presented, containing 10% of each of two alcohols. We show that such dual-alcohol blends have distillation curves closer to that of the base gasoline than single-alcohol blends with 20% of either alcohol individually. At present, ethanol is the only biofuel alcohol available in scale. As other alcohol biofuels become available in the future, it may be advantageous to use them in dual- or multialcohol blends to minimize their impact on fuel volatility.

Realization of Dual Phase High Temperature Heat Release Combustion of Base Gasoline Blends from Oil Refineries and a Study of HCCI Combustion Processes

Realization of Dual Phase High Temperature Heat Release Combustion of Base Gasoline Blends from Oil Refineries and a Study of HCCI Combustion Processes

Aliphatic alcohols as components of fuels for internal combustion engines

International legislation has recently stressed the development and use of environmentally clean automotive fuels. Stiffening of the environmental requirements for auto engines is forcing auto manufacturers all over the world to search for totally new technical solutions to satisfy the approved standards. Since modern machines are becoming increasingly more complicated and their output power is increasing, the composition of the exhaust gases is being increasingly severely regulated. Fuel conservation is now an important goal. The market and environmental protection are the driving force of this process. Of the many ideas, the development of catalytic converters has become the most realistic and effective measure for reducing the toxicity of exhaust gases. Equipping cars with these systems allows “detoxifying” up to 90% of the toxic substances. However, for efficient operation of the catalytic converter, the vehicle must be equipped with a forced fuel injection system, since an ordinary carburetor does not ensure the stable optimum composition of the mixture [1]. Replacing carburetors by injection fuel feed and distribution systems in gasoline engines was an unconditional achievement in automobile manufacture: fuel combustion improved and as a result, the power of the car increased, while fuel consumption and exhaust gas toxicity simultaneously decreased. Autos began to be manufactured with forced fuel injection in 1980. Over 70% of the engines in current foreign automobiles have been equipped with fuel injectors since 1990. The approved Euro-3 and Euro-4 standards for the toxicity of emissions required further improvement in automotive engine designs. Among the other technical innovations, we note the heated converter and the exhaust gas recirculation system. The next step, beginning in 2000, was the mandatory use of onboard diagnostic systems for gasoline engines. They can control vehicle emissions during their entire lifetime. The progress in automotive engine manufacture is constantly imposing new requirements on fuel quality. Environmental protection laws all over the world provide for switching to environmental ly clean vehicles which must run on the corresponding fuels [2]. Ensuring the environmental characteristics of the automobile and preserving them during use are directly dependent on the use of high-quality motor fuels. For this reason, auto manufacturers are turning directly to fuel manufacturers and are instituting joint programs to solve the environmental problems. Base gasoline consisting of equal parts of naphtha from primary distillation and catalytic reforming or cracking with the addition of a high-octane component is usually used for production of standard gasoline [3]. The antiknock effectiveness of the high-octane component is a function of a multitude of factors. The ability of

Effects of Methanol Addition to Gasoline on the Performance and Fuel Cost of a Spark Ignition Engine

This study is concerned with investigating experimentally the effects of methanol blending to base gasoline on the performance and fuel cost of a spark ignition (SI) engine. The fuel blends were prepared by blending 5, 10, 15, and 20 vol % of methanol with a specified amount of base gasoline. These fuel blends were designated as M5, M10, M15, and M20, respectively. Base, leaded, and unleaded gasolines were also used in the study. The experiments were conducted under various engine speeds, spark timings (STs), and compression ratios (CRs). The engine was operated under wide-open-throttle (WOT) conditions. The result of the study showed that the M5 blend yields the best engine performance in terms of the brake mean effective pressure (bmep), while the M20 blend suggests the best performance in terms of brake thermal efficiency (bte). The economical analysis performed in the study is based on both the current blending fuel prices in Turkey and brake-specific fuel consumption (bsfc) of the engine while using base gasoline and gasoline−methanol blends. It was obtained that, in contrast to the improvement of engine performance, methanol blending caused an increase in the consumed fuel cost because of the expensive methanol price in Turkey. The increments in the cost of the fuel blends compared to base gasoline were determined as 18.86, 36.95, 54.20, and 73.01% for M5, M10, M15, and M20, respectively. Uncertainty analysis was also performed in this study, and it was found that the uncertainties in the measurement devices do not have noticeable influences on the variations of engine characteristics.

Effects of Methyl tert-Butyl Ether Addition to Base Gasoline on the Performance and CO Emissions of a Spark Ignition Engine

This study aims at investigating experimentally the effects of methyl tert-butyl ether (MTBE)−gasoline blends on the performance and CO emissions of a spark ignition engine. The blends are prepared by blending 5, 10, 15, and 20 vol % of MTBE with a specified amount of base gasoline. Base, leaded, and unleaded gasolines are also used in the study. The experiments were conducted under various engine speeds, spark timings, and compression ratios. The engine was operated under wide open throttle conditions. The results of the study show that a 10 vol % of MTBE addition to the base gasoline yields the best engine performance and the least CO emissions while the blend containing 15% MTBE and 85% base gasoline suggests the best performance in terms of the brake thermal efficiency.

Desenvolvimento de um equipamento para avaliação do efeito do etanol na pressão de vapor e entalpia de vaporização em gasolinas automotivas

The quality of the gasoline utilized for fueling internal combustion engines with spark ignition is directly affected by the gasoline's properties. Thus, the fuel's properties must be in perfect equilibrium to allow the engine to perform optimally, not only insofar as fuel consumption is concerned, but also in order to reduce the emission of pollutants. Vapor pressure and vaporization enthalpy are important properties of a gasoline determining the fuel's behavior under different operating conditions in internal combustion engines. The study reported here involved the development of a device to determine the vapor pressure and the vaporization enthalpy of formulations containing volumes of 5, 15 and 25% of ethanol in four base gasolines (G1, G2, G3 and G4). The chemical composition of these gasolines was determined using a gas chromatographer equipped with a flame ionization detector (FID).

An Alternative Fuel for Spark Ignition Engines

Alternative fuels have been developed for standard spark ignition engines. The fuels, which contain generic bio-components, maintain all the advantages of ethanol, i.e. the ability to increase considerably the octane number of gasoline and to reduce the amount of harmful pollutants in the exhaust emissions of engines operating on such blends. In contrast with ethanol the new fuel components do not increase the vapour pressure of gasoline-ethanol blends, have a better tolerance to water, and do not increase the fuel consumption. The bio-component-based fuels also compare favourably with mineral-sourced octane boosters such as methyl tert-butyl ether. Additionally reformulation of the base gasoline becomes unnecessary.

Environmental Implications on the Oxygenation of Gasoline with Ethanol in the Metropolitan Area of Mexico City

Motor vehicle emission tests were performed on 12 in-use light duty vehicles, made up of the most representative emission control technologies in Mexico City: no catalyst, oxidative catalyst, and three way catalyst. Exhaust regulated (CO, NOx, and hydrocarbons) and toxic (benzene, formaldehyde, acetaldehyde, and 1,3-butadiene) emissions were evaluated for MTBE (5 vol %)- and ethanol (3, 6, and 10 vol %)-gasoline blends. The most significant overall emissions variations derived from the use of 6 vol % ethanol (relative to a 5% MTBE base gasoline) were 16% decrease in CO, 28% reduction in formaldehyde, and 80% increase in acetaldehyde emissions. A 26% reduction in CO emissions from the oldest fleet (< MY 1991, without catalytic converter), which represents about 44% of the in-use light duty vehicles in Mexico city, can be attained when using 6 vol% ethanol-gasoline, without significant variation in hydrocarbons and NOx emissions, when compared with a 5% vol MTBE-gasoline. On the basis of the emissions results, an estimation of the change in the motor vehicle emissions of the metropolitan area of Mexico city was calculated for the year 2010 if ethanol were to be used instead of MTBE, and the outcome was a considerable decrease in all regulated and toxic emissions, despite the growing motor vehicle population.