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Vicente Gomis - One of the best experts on this subject based on the ideXlab platform.
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isobaric vapor liquid liquid equilibrium and vapor liquid equilibrium for the quaternary system water ethanol cyclohexane Isooctane at 101 3 kpa
Journal of Chemical & Engineering Data, 2010Co-Authors: Ana Pequenin, Juan Carlos Asensi, Vicente GomisAbstract:Experimental isobaric vapor−liquid−liquid and vapor−liquid equilibrium data for the ternary system water (1) −cyclohexane (2) −Isooctane (3) and the quaternary system water (1) −ethanol (2) −cyclohexane (3) −Isooctane (4) were measured at 101.3 kPa. An all-glass, dynamic recirculating still equipped with an ultrasonic homogenizer was used to determine the VLLE. The results obtained show that the system does not present quaternary azeotropes. The point-by-point method by Wisniak for testing the thermodynamic consistency of isobaric measurements was used to test the equilibrium data.
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dehydration of ethanol using azeotropic distillation with Isooctane
Industrial & Engineering Chemistry Research, 2007Co-Authors: Vicente Gomis, R Pedraza, Olga Frances, And Alicia Font, Juan Carlos AsensiAbstract:The viability of an azeotropic distillation process using 2,2,4-trimethylpentane (Isooctane) as an entrainer to dehydrate ethanol and obtain a mixture of ethanol + Isooctane without water is analyzed utilizing both an experimental procedure and an equilibrium-model-based simulation. The direct manufacture of this mixture of ethanol + Isooctane for use as gasoline should avoid the additional cost of dehydrating ethanol in an earlier process. Experimental results indicate that azeotropic distillation allows obtaining mixtures of Isooctane + ethanol with water concentrations lower than 50 ppm. The results indicate that the most critical parameter for this process is the reboiler heat duty. Low values of this parameter ( 3.6 kJ/g of feed ethanol) the azeotropic distillation column does not function properly, as the top stream condenses giving only one liquid phase. Results of the equilib...
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application of Isooctane to the dehydration of ethanol design of a column sequence to obtain absolute ethanol by heterogeneous azeotropic distillation
Industrial & Engineering Chemistry Research, 2003Co-Authors: Alicia Font, Juan Carlos Asensi, Francisco Ruiz, Vicente GomisAbstract:Consistent vapor−liquid (VLE) and vapor−liquid−liquid equilibrium (VLLE) data for the ternary system water + ethanol + Isooctane (2,2,4-trimethylpentane) are reported at 101.3 kPa at temperatures in the range of 341−352 K. An all-glass, dynamic recirculating still equipped with an ultrasonic homogenizer has been used in the determination of the VLLE. The experimental data obtained demonstrates the existence of a ternary heterogeneous azeotrope at 68.7 °C with a composition of 0.198, 0.436, and 0.366 mole fractions of water, ethanol, and Isooctane, respectively. The VLLE data were correlated simultaneously with VLE data by using the UNIQUAC model. The parameters obtained allow the development of suitable distillation sequences to obtain pure ethanol or a mixture of ethanol and Isooctane.
Juan Carlos Asensi - One of the best experts on this subject based on the ideXlab platform.
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isobaric vapor liquid liquid equilibrium and vapor liquid equilibrium for the quaternary system water ethanol cyclohexane Isooctane at 101 3 kpa
Journal of Chemical & Engineering Data, 2010Co-Authors: Ana Pequenin, Juan Carlos Asensi, Vicente GomisAbstract:Experimental isobaric vapor−liquid−liquid and vapor−liquid equilibrium data for the ternary system water (1) −cyclohexane (2) −Isooctane (3) and the quaternary system water (1) −ethanol (2) −cyclohexane (3) −Isooctane (4) were measured at 101.3 kPa. An all-glass, dynamic recirculating still equipped with an ultrasonic homogenizer was used to determine the VLLE. The results obtained show that the system does not present quaternary azeotropes. The point-by-point method by Wisniak for testing the thermodynamic consistency of isobaric measurements was used to test the equilibrium data.
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dehydration of ethanol using azeotropic distillation with Isooctane
Industrial & Engineering Chemistry Research, 2007Co-Authors: Vicente Gomis, R Pedraza, Olga Frances, And Alicia Font, Juan Carlos AsensiAbstract:The viability of an azeotropic distillation process using 2,2,4-trimethylpentane (Isooctane) as an entrainer to dehydrate ethanol and obtain a mixture of ethanol + Isooctane without water is analyzed utilizing both an experimental procedure and an equilibrium-model-based simulation. The direct manufacture of this mixture of ethanol + Isooctane for use as gasoline should avoid the additional cost of dehydrating ethanol in an earlier process. Experimental results indicate that azeotropic distillation allows obtaining mixtures of Isooctane + ethanol with water concentrations lower than 50 ppm. The results indicate that the most critical parameter for this process is the reboiler heat duty. Low values of this parameter ( 3.6 kJ/g of feed ethanol) the azeotropic distillation column does not function properly, as the top stream condenses giving only one liquid phase. Results of the equilib...
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application of Isooctane to the dehydration of ethanol design of a column sequence to obtain absolute ethanol by heterogeneous azeotropic distillation
Industrial & Engineering Chemistry Research, 2003Co-Authors: Alicia Font, Juan Carlos Asensi, Francisco Ruiz, Vicente GomisAbstract:Consistent vapor−liquid (VLE) and vapor−liquid−liquid equilibrium (VLLE) data for the ternary system water + ethanol + Isooctane (2,2,4-trimethylpentane) are reported at 101.3 kPa at temperatures in the range of 341−352 K. An all-glass, dynamic recirculating still equipped with an ultrasonic homogenizer has been used in the determination of the VLLE. The experimental data obtained demonstrates the existence of a ternary heterogeneous azeotrope at 68.7 °C with a composition of 0.198, 0.436, and 0.366 mole fractions of water, ethanol, and Isooctane, respectively. The VLLE data were correlated simultaneously with VLE data by using the UNIQUAC model. The parameters obtained allow the development of suitable distillation sequences to obtain pure ethanol or a mixture of ethanol and Isooctane.
Shijin Shuai - One of the best experts on this subject based on the ideXlab platform.
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ultra high speed imaging and oh lif study of dmf and mf combustion in a disi optical engine
Applied Energy, 2014Co-Authors: Changzhao Jiang, Shijin ShuaiAbstract:Abstract The furan series of chemicals such as 2,5-dimethylfuran (DMF) and 2-methylfuran (MF) are promising alternative fuel candidates for internal combustion engines due to their advantages compared to gasoline. However, no research has been published on the optical diagnostics of their combustion process in the engine cylinder. In this paper, the planar laser-induced fluorescence (PLIF) technique has been used to investigate the OH distribution in the flames of DMF and MF in a direct injection spark ignition (DISI) optical engine. The images of OH-LIF in the combustion process combined with the high-speed imaging and heat release data at two different engine load conditions (4.5 bar and 5.5 bar IMEP) for DMF and MF were studied and compared with Isooctane, the reference fuel representing gasoline. Interesting correlations were found between the heat release rate, flame speed, flame area and PLIF of OH for the tested fuels at the two loads and the proposed correlations have also been confirmed by using the data in previous studies. MF is shown to combust significantly faster than DMF and Isooctane. It is found that at 4.5 bar IMEP, the pressure trace, flame speed and flame area growth rate of DMF are very close to those of Isooctane, but lower than those of MF. The combustion phase of MF is earlier and the duration is shorter than DMF and Isooctane. Normalized LIF signals show that MF always has the maximum values and the higher IMEP will advance the time of the OH peak. The rate of heat release (ROHR) matches the trend of OH development well before the flame goes beyond the visible area. Finally, a correlation between the results of MFB and OH-LIF reveals that the three fuels follow a similar trend, indicating that the OH generation matches the MFB data well, irrespective of the fuel. The correlations between the flame area and OH-LIF signal are also discussed.
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Laminar burning characteristics of 2-methylfuran and Isooctane blend fuels
Fuel, 2014Co-Authors: Changzhao Jiang, Haichun Ding, Shijin ShuaiAbstract:Abstract2-Methylfuran (MF) has become very attractive due to the recent breakthrough in its production method using the process of dehydration and hydrogenolysis of fructose. MF–gasoline blended fuel has been considered as a potential choice of alternative fuel pathway for spark ignition (SI) engines, as have other biofuel blends. Isooctane is used to represent gasoline in fundamental studies of gasoline blended fuels, however, little is known about the laminar burning characteristics of MF–Isooctane blended fuels. In this study, high-speed schlieren photography is used to investigate the laminar burning characteristics of gaseous MF–Isooctane at varying temperatures and equivalence ratios with an initial pressure of 0.1MPa in a constant-volume vessel. The outwardly spherical flame method is used to determine the stretched flame speeds. The un-stretched flame speeds, Markstein lengths, Markstein number, laminar burning velocities and laminar burning flux of MF20 (20% MF and 80% Isooctane) and MF50 (50% MF and 50% Isooctane) under different equivalence ratios and temperatures are then deduced and compared to MF and Isooctane. The results show that the un-stretched flame speeds and laminar burning velocities of MF20 and MF50 are between those of MF and Isooctane under all conditions. The peak un-stretched flame speeds of the blends occur in an equivalence ratio range of 1.1–1.2 at all temperatures, closer to the case of MF at higher temperatures. Both blended fuels have Markstein lengths closer to Isooctane at an equivalence ratio lower than 1.2 at all temperatures. The burning velocities of MF50 are very close to the average values for MF and Isooctane, particularly at 393K. MF in the blended fuel presents larger effects on burning velocities at higher temperatures
Zuohua Huang - One of the best experts on this subject based on the ideXlab platform.
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laminar flame characteristics and kinetic modeling study of methanol Isooctane blends at elevated temperatures
Fuel, 2016Co-Authors: Weijie Zhang, Wu Jin, Yongliang Xie, Zuohua HuangAbstract:Abstract Laminar flame speeds of methanol-Isooctane blends were experimentally determined using the spherically propagating flame in a constant volume chamber at two initial temperatures (363 and 393 K), different blending ratios of methanol in liquid volume (0%, 20%, 40%, 80%, 100%), and over equivalence ratios of 0.7–1.6. Nonlinear methodology was employed to remove the stretch effect in the data processing. Results indicate that laminar flame speeds of methanol flame reach the peak at equivalence ratio around 1.2 and that of Isooctane at equivalence ratio around 1.1. For the mixtures with less than 40% methanol, laminar flame speeds show moderate increase at all equivalence ratios. However, further increasing methanol addition will greatly accelerate laminar flame speeds at rich mixture sides but give slight change at lean mixture sides. Markstein length shows an increase tendency with the methanol addition at the equivalence ratios larger than a critical value while Markstein length gives a decrease tendency at the equivalence ratios smaller than the critical value. The critical equivalence ratio is between 1.2 and 1.3. Among the thermal effect, diffusive effect and kinetic effect, the kinetic effect was found to be the major factor bringing the variation of laminar flame speed with the variation of blending ratio. A kinetic model (IM model) was developed on the basis of the Isooctane model of Chaos et al. (2007). The IM model shows good prediction on measured laminar flame speeds under all conditions. Reaction pathway reveals that the HCO and H productions are promoted while the productions of stable species are inhibited in the case of methanol addition into the Isooctane at rich mixture sides, resulting in the laminar flame speed enhancement. These behaviors are verified from the sensitivity analysis and the concentrations of the reactive radicals.
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laminar flame characteristics of c1 c5 primary alcohol Isooctane blends at elevated temperature
Energies, 2016Co-Authors: Wu Jin, Zuohua HuangAbstract:The laminar combustion characteristics of blends of Isooctane and C1–C5 primary alcohols (i.e., methanol, ethanol, n-propanol, n-butanol and n-pentanol) were investigated using the spherical expanding flame methodology in a constant volume chamber at various equivalence ratios and volume fractions of alcohol. The stretch effect was removed using the nonlinear methodology. The results indicate that the laminar flame speeds of alcohol-Isooctane blends increase monotonously with the increasing volume fraction of alcohol. Among the five alcohols, the addition of methanol is identified to be the most effective in enhancing laminar flame speed. The addition of ethanol results in an approximately equivalent laminar flame speed enhancement rate as those of n-propanol, n-butanol and n-pentanol at ratios of 0.8 and 1.5, and a higher rate at 1.0 and 1.2. An empirical correlation is provided to describe the laminar flame speed variation with the volume fraction of alcohol. Meanwhile, the laminar flame speed increases with the mass content of oxygen in the fuel blends. At the equivalence ratio of 0.8 and fixed oxygen content, similar laminar flame speeds are observed with different alcohols blended into Isooctane. Nevertheless, with the increase of equivalence ratio, heavier alcohol-Isooctane blends tend to exhibit higher values. Markstein lengths of alcohol-Isooctane blends decrease with the addition of alcohol into Isooctane at 0.8, 1.0 and 1.2, however they increase at 1.5. This is consistent with the behavior deduced from the Schlieren images.
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flame front instabilities of outwardly expanding Isooctane n butanol blend air flames at elevated pressures
Energy & Fuels, 2014Co-Authors: Xinyi Zhang, Chenglong Tang, Zuohua HuangAbstract:Experiments were conducted in a constant volume bomb filled with Isooctane/n-butanol blend–air mixtures over a wide range of n-butanol blending ratios, equivalence ratios, and initial pressures. Hi...
Guillaume Broustail - One of the best experts on this subject based on the ideXlab platform.
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experimental determination of laminar burning velocity for butanol iso octane and ethanol iso octane blends for different initial pressures
Fuel, 2013Co-Authors: Guillaume Broustail, Fabien Halter, Patrice Seers, Gladys Moreac, Christine MounaimrousselleAbstract:The comparison of butanol/Isooctane blends with an ethanol/Isooctane blend was characterized with respect to laminar combustion, by using the spherical expanding flame methodology, in a constant volume vessel. This paper presents the results obtained for blends with alcohol concentrations of 0%, 25%, 50%, 75% and 100% (in volume) and an equivalence ratio ranging from 0.7 to 1.4, at different initial pressures (0.1, 0.3, 0.5 and 1.0 MPa) and an initial temperature of 423 K. The addition of alcohol to Isooctane increases the laminar burning velocity, but increasing the initial pressure limits this increase. From burned gas Markstein length estimates, the flame of ethanol/Isooctane and air mixture seems to be less sensitive to the total stretch rate and thermo-diffusive instabilities. From experimental data, a correlation with laminar burning velocity is suggested as a function of initial pressure, equivalence ratio and alcohol concentration.
