Isobaric Vapor–Liquid Equilibrium for the Mixture of Neohexane,Cyclopentane and N,N-Dimethylformamide at 101.3 kPa

The vapor–liquid phase equilibrium (VLE) data for binary systems of neohexane?+?cyclopentane, neohexane?+?N,N-dimethylformamide (DMF), cyclopentane?+?DMF and ternary system of neohexane?+?cyclopentane?+?DMF were determined with a modified Rose still at 101.3 kPa, and all the binary data passed the Wisniak’s test (D?<?5), which accorded with the thermodynamic consistency. Three activity coefficient models namely, Wilson, NRTL and UNIQUAC were used to correlate VLE data and get binary interaction parameters, then the ternary VLE data of neohexane?+?cyclopentane?+?DMF were estimated based on these model parameters using Aspen Plus software. The estimation values of the three models agree well with the experimental data (σ(T)?<?0.5 K). Moreover, the analysis of the effect of DMF on the vapor–liquid phase equilibrium shows that DMF can act as an effective extractant for the system studied.

     

Entrainers Selection and Vapor–Liquid Equilibrium Measurements for Separation of p-Xylene from Ethylbenzene at 101.3 kPa

Journal of Solution Chemistry - In this paper, the separation of the p-xylene and ethylbenzene was explored. The COSMO-SAC-UNIFAC model, σ-profile analysis, solvent power and selectivity were...     

Liquid–Liquid Equilibrium Data for 1-Ethyl-3-methylimidazolium Acetate–Thiophene–Diesel Compound: Experiments and Correlations

Extraction of thiophene from cyclohexane, isooctane and toluene were performed using the ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]) at T=298.15 K. The liquid?Cliquid equilibrium (LLE) experiments were performed on three systems, namely: [EMIM][OAc]?Cthiophene?Ccyclohexane, [EMIM][OAc]?Cthiophene?Cisooctane and [EMIM][OAc]?Cthiophene?Ctoluene. The LLE data showed that [EMIM][OAc] has a higher selectivity at low concentration of thiophene and also showed that the hydrocarbon-rich phase is free of ionic liquid. This implies that there will be no cross contamination and the ionic liquid will be a non-pollutant in fuel after extraction. Further, the amount of hydrocarbon in the ionic-liquid-rich phase is very small. This implies that ionic liquid can be regenerated with negligible loss of fuel. LLE data was then correlated using the NRTL and UNIQUAC models. These showed root mean square deviation (RMSD) values of 0.82?% and 1.46?% for the isooctane system, 1.37?% and 1.57?% for the cyclohexane system and 1.39?% and 1.53?% for the toluene system.     

Experimental Study of Vapor–Liquid Equilibrium Data for Acetone + Methanol + 1-Methyl-3-octylimidazolium Thiocyanate

An experimental study on the isobaric vapor–liquid equilibria for the ternary system of acetone?+?methanol?+?1-methyl-3-octylimidazolium thiocyanate ([Omim][SCN]) as well as the two acetone?+?ionic liquid (IL) and methanol?+?IL binary systems was performed at 100 kPa using a recirculating still (VLE 602 Fischer apparatus). A low IL mole fraction of 0.027 was found to be sufficient break the azeotrope due to the high and specific interactions with acetone and methanol. The nonrandom two-liquid model was used to represent the experimental data. The results are compared with those in the literature for the same mixed solvent system using other ILs.     

Liquid–Liquid Equilibrium of the Quaternary Systems <Emphasis Type="Italic">n</Emphasis>-Octane or Decane + Toluene + Dimethyl Sulfoxide + Methanol or Ethanol at 298.15 K: Experimental Data and Correlation

In this work, the effect of addition of methanol or ethanol to dimethyl sulfoxide to extract toluene from alkanes was studied. Liquid–liquid equilibria data of the four quaternary systems: {methanol (1)?+?DMSO (2)?+?octane (3)?+?toluene (4)}, {ethanol (1)?+?DMSO (2)?+?octane (3)?+?toluene (4)}, {methanol (1)?+?DMSO (2)?+?decane (3)?+?toluene (4)} and {ethanol (1)?+?DMSO (2)?+?decane (3)?+?toluene (4)} were obtained at 298.15 K and 101.3 kPa. The thermodynamic consistency of the experimental data was verified using the Othmer–Tobias and Hand tests. Selectivities and distribution ratios of the four quaternary systems were calculated from experimental data to evaluate the capacity of these two mixed solvents to extract toluene from octane and decane. A comparison of the results obtained was carried out. The NRTL model was used to correlate experimental data and the correlated results are in good agreement with experimental data.     

Solid–Liquid Stable Equilibrium of the Quaternary System LiCl + NaCl + Li2SO4 + Na2SO4 + H2O at 288.15 K

Journal of Solution Chemistry - In this study, the isothermal saturation method was applied to obtain the data for solid–liquid equilibria in a system consisting of four solids...     

Isobaric Binary and Ternary Vapor–Liquid Equilibrium for the Mixture of n-Hexane,Methylcyclopentane and N-Methylpyrrolidone

Journal of Solution Chemistry - The vapor–liquid phase equilibrium (VLE) data for binary systems of: n-hexane?+?methylcyclopentane, n-hexane?+?N-methylpyrrolidone...     

DFT Study on the Structure of Ionic Liquid 1-Ethyl-3-methylimidazolium Hexafluorophosphate

1 INTRODUCTION Ionic compounds generally have high melting points and always exist in solid state since they are main- tained by electrovalent bonds. Ionic Liquids (ILs), which are liquids at or near ambient temperature, have been a class of ionic compounds extensively studied experimentally and theoretically in recent years[1, 2]. ILs consist exclusively of anions and ca- tions and do not contain any neutral molecule. They have many attractive properties, such as low vapor pressure, no…     

Solution Properties of Ternary D-Glucose + 1-Ethyl-3-methylimidazolium Ethyl Sulfate + Water Solutions at 298.15 K

The effect of an ionic liquid, 1-ethyl-3-methylimidazolium ethyl sulfate ([EMIm]ESO₄), on the thermophysical properties of aqueous D-glucose solutions including density, viscosity, and electrical conductivity have been investigated at 298.15 K. Using these properties, the apparent molar volumes, V _φ , the viscosity B-coefficients and the molar conductivities, Λ _m, have been computed for the ternary D-glucose + [EMIm]ESO₄+water solutions. The V _φ values were used to calculate the standard partial molar volumes, V_f⁰V_{phi}^{0}, and transfer volumes, D_trV_f⁰Delta_{mathrm{tr}}V_{phi}^{0}, of D-glucose from water to aqueous ionic liquid solutions. These volumetric parameters, for all the solutions studied, are positive and increase monotonically with increasing the concentration of [EMIm]ESO₄. These observations have been interpreted in terms of the interactions between D-glucose and ionic liquid in the aqueous solution. The viscosity data were analyzed in terms of the Jones-Dole equation to determine the values of the viscosity B-coefficients. The calculated conductometric parameters, the limiting molar conductivities, Λ ₀, the association constants, K _a, and the Walden products, Λ ₀ η, for [EMIm]ESO₄, decrease with increasing concentration of D-glucose. This trend suggests that the ions of an ionic liquid do not have the same hydrodynamic size in the presence of D-glucose molecules (ILs) and consequently provides evidence for the dehydration effect of the ionic liquid in aqueous D-glucose solutions.     

Erratum to: “Fractionation of Wood with Binary Solvent 1-Butyl- 3-methylimidazolium Acetate + Dimethyl Sulfoxide”

Russian Journal of Applied Chemistry - In title section and ACKNOWLEDGMENTS Arktika Center of Collective Use of Scientific Equipment should be replaced by Core Facility Center...     

Isobaric vapor–liquid–liquid equilibrium and vapor–liquid equilibrium for the system water–ethanol-1,4-dimethylbenzene at 101.3 kPa

An all-glass, dynamic recirculating still equipped with an ultrasonic homogenizer has been used to determine vapor–liquid (VLE) and vapor–liquid–liquid (VLLE) equilibria. Consistent data have been obtained for the ternary water + ethanol + p-xylene system at 101.3 kPa for temperatures in the range of 351.16–365.40 K. Experimental results have been used to check the accuracy of the UNIFAC, UNIQUAC and NRTL models in the liquid–liquid region of importance in the dehydration of ethanol by azeotropic distillation.     

Vapor–liquid equilibria of the binary mixtures formed by nitromethane with five alkyl alkanoates at 101.3 kPa

Vapor–liquid equilibria were measured at 101.3 kPa, in a range of temperatures from 350.28 to 374.69 K, for five binary mixtures formed by nitromethane with ethyl acetate, propyl acetate, isopropyl acetate, methyl propionate, and ethyl propionate. Calculations of nonideality of the vapor phase were made with Soave–Redlich–Kwong equation of state. Thermodynamic consistency of data was tested via Herington analysis. Two systems show minimum boiling azeotropes. The experimental VLE data were reduced and binary parameters for four liquid models, such as van Laar, Wilson, NRTL and UNIQUAC, were fitted. A comparison of model performances was made by using the criterion of average absolute deviations in boiling point and in vapor-phase composition.     

Isobaric vapour–liquid equilibrium for the binary systems formed by a cyclic ether and bromocyclohexane at 40.0 and 101.3 kPa

Experimental data of vapour–liquid equilibrium (VLE) for the binary systems tetrahydrofuran, or tetrahydropyran, or 2-methyl-tetrahydrofuran, or 2,5-dimethyl-tetrahydrofuran with bromocyclohexane have been measured in isobaric conditions at two pressures, 40.0 and 101.3?kPa. The equipment used was a dynamic recirculating still. The consistency of the measured VLE data has been tested with the Van Ness’ point-to-point method. The activity coefficients have been correlated with the mole fraction through Wilson, NRTL and UNIQUAC equations.     

Liquid–Liquid Equilibrium of Water + 1-Propanol or 1-Butanol + Dibutyl Ether Ternary Systems: Measurements and Correlation at Three Temperatures

Liquid–liquid equilibrium (LLE) date for the ternary systems of {water?+?1-propanol?+?dibutyl ether (DBE)} and (water?+?1-butanol?+?DBE) were determined at T?=?(293.15, 303.15, 308.15) K under atmospheric pressure. Distribution coefficients and separation factors of 1-propanol in the mixtures were calculated and are discussed. The influence of temperature on the liquid phase regions was analyzed. In addition, the experimental values were correlated well with the modified and extended UNIQUAC models; the modified UNIQUAC model represents the data better than the extended UNIQUAC model.     

Physical properties of the ternary mixture ethanol + water + 1-hexyl-3-methylimidazolium chloride at 298.15 K

In this work, densities and refractive indices of the ternary mixture ethanol?+?water?+?1-hexyl-3-methylimidazolium chloride ([C₆mim][Cl]) and of the binary systems containing the ionic liquids (ILs) have been measured at 298.15?K and atmospheric pressure. Excess molar volumes and changes of refractive indices on mixing were determined from experimental data. The binary data were correlated with the Redlich–Kister equation, while the Cibulka equation was applied for the ternary system.     

Isothermal Vapor–Liquid Equilibria for the Ternary System 2-Propanol + Tetrahydrofuran + 1-Chlorobutane at 25°C

Isothermal vapor–liquid equilibria (VLE) for mixtures containing 2-propanol + tetrahydrofuran + 1-chlorobutane have been measured using a modified version of a Boublik–Benson still at 25°C. A test of thermodynamic consistency, like the McDermott–Ellis method was applied to the activity coefficients. Excess molar Gibbs free energies were calculated over the entire range composition. Different expressions existing in the literature were used to predict activity coefficients.     

Comment on “Isobaric (vapour + liquid) equilibria for the (1-propanol + 1-butanol) binary mixture at (53.3 and 91.3) kPa”

The (vapor + liquid) equilibrium values reported by Mohsen-Nia and Memarzadeh appear to be flawed. In particular, neither the reported experimental activity coefficients are consistent with the reported composition data nor the reported model parameters can be used to adequately represent their experimental data.     

Isobaric vapour–liquid equilibria for the binary systems 4-methyl-2-pentanone + 1-butanol and + 2-butanol at 20 and 101.3 kPa

Isobaric vapour–liquid equilibrium (VLE) measurements for the binary systems 4-methyl-2-pentanone + 1-butanol and 4-methyl-2-pentanone + 2-butanol are reported at 20 and 101.3 kPa. The system 4-methyl-2-pentanone + 1-butanol presents a minimum boiling point azeotrope at both pressures (20 and 101.3 kPa) and the system 4-methyl-2-pentanone + 2-butanol presents only a minimum boiling azeotrope at 20 kPa. In both systems, which deviate positively from ideal behaviour, the azeotropic composition is strongly dependent on pressure. The activity coefficients and boiling points of the solutions were correlated with its composition by the Wilson, UNIQUAC, and NRTL models for which the parameters are reported.