Vapour Pressures Of Binary Mixtures Research Articles

Vapor Pressure Measurements for Binary Mixtures Containing Ionic Liquid and Predictions by the Conductor-like Screening Model for Real Solvents

The vapor pressures for binary systems containing the ionic liquid (IL) 1-ethyl-3-methylimidazoliun tetrafluoroborate ([EMIM][BF4]) and a solute were measured with a modified equilibrium still, and the solutes investigated were benzene, toluene, thiophene, and water. The results indicate that the IL [EMIM][BF4] produces an obvious effect on the vapor pressures of binary systems, and the vapor pressures increase with the temperature. The vapor pressures of binary mixtures (i.e., [EMIM][BF4] + benzene, [EMIM][BF4] + thiophene, and [EMIM][BF4] + toluene) first increase with the increase of mole fraction of the solute, and then almost keep stable. However, the vapor pressures of the mixture of water and [EMIM][BF4] increase linearly with the increase of mole fraction of water. The vapor pressure experimental data for the binary systems were compared with the predicted values by the conductor-like screening model for real solvents (COSMO-RS) model. The results demonstrate that the COSMO-RS model gives quantita...

Vapor Pressures and Activity Coefficients of Methanol in Binary Mixtures with 1-Hexyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide

The vapor pressures of binary mixtures containing methanol and ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [HMIM][NTf2] were investigated at temperatures ranging from 274.15 K to 413.15 K using the two different setups with static method. The activity coefficients γi of methanol in the [HMIM][NTf2] and osmotic coefficients ϕi of the [HMIM][NTf2] have been determined from the vapor–liquid equilibria data and are described using the Clasius−Clapeyron and NRTL equation.

Isothermal vapor–liquid equilibria and excess Gibbs free energies in some binary nitroalkane + chloroalkane mixtures at temperatures from 298.15 K to 318.15 K

The vapor pressures of binary mixtures of cloroalkane (1-chlorobutane, 1-chloropentane)+nitromethane or nitroethane were measured at temperatures between 298.15K and 318.15K. The vapor pressures vs. liquid phase composition data have been used to calculate the activity coefficients of the two components, and the excess molar Gibbs energies GE for the mixtures, using Barker's method. Redlich–Kister, Wilson, NRTL and UNIQUAC equations, taking into account the vapor phase imperfection in terms of the 2-nd virial coefficient, have represented the GE values. No significant difference between GE values obtained with these equations has been observed. The results indicate that all the systems show positive deviations from Raoult's law. The experimental VLE data were analyzed in terms of the modified UNIFAC (Dortmund) model.

Influence of the Structure of the Cation of Ionic Liquids on the Vapor Pressure and Osmotic Coefficients in their Binary Mixtures with 1-Propanol

The osmotic and activity coefficients and vapor pressures of binary mixtures containing the alcohol 1-propanol and the ionic liquids 1-ethyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide, C2MpyNTf2, 1-propyl-3- methylpyridinium bis(trifluoromethylsulfonyl)imide, C3MpyNTf2, 1-butyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide, C4MpyNTf2 and 1-butyl-3-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, C4MpyrNTf2 were determined at T = 323.15 K using the vapor pressure osmometry technique. The experimental osmotic coefficients were correlated using the Extended Pitzer model of Archer obtaining standard deviations lower than 0.060. The mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures were calculated from the parameters of the Extended Pitzer model of Archer. From the experimental determination, the influence of the alkyl-side chain of the cation and of the cation itself on the osmotic and activity coefficients and on the vapor pressures can be analyzed.

Study of the influence of the structure of the alcohol on vapor pressures and osmotic coefficients of binary mixtures alcohol + 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide at T = 323.15 K

The osmotic and activity coefficients and vapor pressures of binary mixtures containing the alcohols 1-propanol, 2-propanol, 1-butanol, 2-butanol and 1-pentanol and the ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, C 6MimNTf 2, were determined at T = 323.15 K using the vapor pressure osmometry technique. The experimental osmotic coefficients were correlated using the Extended Pitzer model of Archer and the MNRTL model, obtaining standard deviations lower than 0.020 and 0.049, respectively. The mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures were calculated from the parameters of the Extended Pitzer model of Archer. Besides the effect of the alkyl-chain of the alcohol and the position of the alcohol group, the effect of the alkyl-side chain of the cation of the ionic liquid can be assessed comparing the experimental results with those previously obtained for imidazolium bis(trifluoromethylsulfonyl)imide ionic liquids with different alkyl-side chain lengths.

Determination and modelling of osmotic coefficients and vapour pressures of binary systems 1- and 2-propanol with C nMimNTf 2 ionic liquids ( n = 2, 3, and 4) at T = 323.15 K

The osmotic and activity coefficients and vapour pressures of binary mixtures containing 1-propanol, or 2-propanol and imidazolium-based ionic liquids with bis(trifluoromethylsulfonyl)imide as anion (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, C 2MimNTf 2, 1-methyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide, C 3MimNTf 2, and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, C 4MimNTf 2) were determined at T = 323.15 K using the vapour pressure osmometry technique. The experimental osmotic coefficients were correlated using the extended Pitzer model modified by Archer and the MNRTL model, obtaining standard deviations lower than 0.033 and 0.064, respectively. The mean molal activity coefficients and the excess Gibbs free energy for the mixtures studied were calculated from the parameters of the extended Pitzer model modified by Archer. Besides the effect of the alkyl-chain of the cation, the effect of the anion can be assessed comparing the experimental results with those previously obtained for imidazolium ionic liquids with sulphate anions.

Isothermal vapour-liquid equilibria in cyclohexanone + dichloroalkane binary mixtures at temperatures from 298.15 to 318.15K

The vapour pressures of binary mixtures of cyclohexanone + dichloroalkane (1,3-dichloropropane and 1,4-dichlorobutane) were measured at temperatures between 298.15 K and 318.15 K. The vapour pressures vs. liquid phase composition data were used to calculate the activity coefficients of the two components and the excess molar Gibbs energies GE for the mixtures, using the Barker method and the Redlich-Kister, Wilson, NRTL and UNIQUAC equations, taking into account the vapour phase imperfection in terms of the 2nd virial coefficient. No significant difference between the GE values obtained with these equations was observed.

Thermodynamics of n-octane+hexynes binary mixtures

The vapor pressures of binary mixtures of n-octane+hex-2-yne, or hex-3-yne and of the three pure components were measured by means of a static device at temperatures between 263 and 343 K. Molar excess Gibbs energies G E were calculated for several constant temperatures, taking into account the vapor phase imperfection in terms of the second molar virial coefficients, and were fitted to the Redlich–Kister equation. Calorimetric excess enthalpy H E measurements for n-octane+hex-2-yne, +hex-3-yne, or +hex-1-yne are also reported at 303.15 K. These data, along with previous vapor–liquid equilibrum data for the n-octane+hex-1-yne mixture, are examined on the basis of DISQUAC, an extended quasichemical group-contribution model. In terms of DISQUAC, the mixtures studied were characterized by only one type of contact: aliphatic/alkyne. The interchange coefficients are not available in the literature, and are estimated in this work. The model consistently describes the excess functions G E and H E of the investigated n-octane+alkynes mixtures.

Vapour pressures of binary mixtures of t-butyl alcohol and water

The total vapour pressures of t-butyl alcohol (TBA) and water mixtures have been measured at 283.15, 288.15, 293.15, 298.15 and 303.15 K, respectively. Maxima and minima were observed in the vapour pressure versus concentration curves at the three lowest temperatures. The anomalous behaviour of the solution can be explained by the existence of a clathrate-like structure, which has been suggested by other authors.

VLE data and UNIFAC-parameters of binary mixtures with methylisocyanate

Vapor pressures of binary mixtures of methylisocyanate with hexane and benzene in the temperature range of −5°C to 200°C have been measured. There was no indication of thermal instability or polymerisation within that range. Based on the experimental VLB data, UNIFAC interaction parameters have been correlated for the new main group of isocyanate. The parameters allow good prediction of VLE from different binary systems composed of molecules with the same functional groups. In addition, literature data of binary mixtures were taken to calculate interaction parameters of chlorine-substituted aliphatic hydrocarbon-groups with the isocyanate group.

Vapor pressures of binary mixtures of carbon dioxide with benzene, n-hexane and cyclohexane up to 7 MPa

The total vapor pressures of three CO 2C 6 hydrocarbon systems; CO 2benzene, CO 2n-hexane, and CO 2cyclohexane systems, have been measured at 273.15, 283.15, 298.15 and 303.15 K over the whole composition range by a bubble point method. For the CO 2n-hexane system, the densities of the liquid mixtures have also been measured. From the data and the calculated results by the Peng—Robinson equation of state, the activity coefficients of CO 2 and the Henry's constants of CO 2 in CO 2C 6 hydrocarbon systems have been obtained. The vapor pressure data have been compared with the results calculated by the Barker's method and by the Peng—Robinson equation of state with the use of four mixing models.

Thermodynamic study of association in t-butylamine, according to a two-constant model

Vapour pressures of binary mixtures of t-butylamine + sooctane, or + benzene, at 20, 30 and 40 °C, have been measured, by a static method. The activity coefficients have been represented by Redlich-Kister, Wilson, and NRTL equations. A two-constant model has been tested to describe amine association.

VAPOUR PRESSURES AND BOILING POINTS OF BINARY MIXTURES OF HYDROGEN PEROXIDE AND WATER

The total vapour pressures of binary mixtures of hydrogen peroxide and water have been measured by means of the static method at 30, 45, and 60 °C. over the entire range of concentration. The vapour-pressure–composition curves have been found to exhibit large negative deviations from Raoult's law, but no minimum. A special apparatus and experimental technique were devised that enabled the composition of the vapour to be determined in each case. These data were used to obtain the partial pressures of both components. The values thus found are in good agreement with those calculated from the total vapour pressures by means of the Duhem Margules equation. The activities of water and hydrogen peroxide in their solutions have been calculated and interpreted on the basis of the polarity of the two pure liquids.The normal boiling point and latent heat of vaporization of the solutions were obtained by extrapolation of the vapour pressure data. The results are important in connection with the distillation of aqueous solutions of hydrogen peroxide.

Societies and Academies

LONDON. Faraday Society, December 15, 1919.—Prof. A. W. Porter, vice-president, in the chair.—A. G. Tarrant: The measurement of physical properties at high temperatures. An account is given of experiments made upon refractory materials with the view of measuring certain physical properties at high temperatures, particular attention being paid to thermal expansion, tensile strength, and thermal conductivity.—Lieut. W. A. Macfadyen: An aspect of electrolytic iron deposition. The experiments detailed were carried out in seeking the best conditions for obtaining thick, hard, adherent deposits of iron on steel-mechanism parts which had been machined too much or worn down in a few places, and thus rendered useless, so as to enable the scrapped parts to be replaced in use after treatment.—J. G. Williams: The electrolytic formation of perchlorate. It is pointed out that present practice in electrolytic preparation of perchlorate uses much higher temperature of liquor and current density than is given in text-books.—Prof. A. W. Porter: The vapour pressure of binary mixtures. In order to remove _ difficulties in connection with the proof of the Duhem-Margules formula for the vapour pressures of binary mixtures, a simplified proof is given which makes clear the extent of the usual approximations in each step of the proof.—Prof. E. D. Campbell: The solution theory of steel and the influence of changes in carbide concentration on the electrical resistivity. Baly's force-field theory is applied to the case of the solid solution of the non-ferrous elements in steel. The experimental portion of the paper describes a research on the influence of the decarburisation by means of hydrogen of a series of alloy steels on the electrical resistivity, when the metal is in both the annealed and hardened condition. —S. Horiba: Some relations between the solubilities of solutes and their molecular volumes.—Dr. E. J. Hartung: (i) An accurate method for the determination of vapour pressure. (2) Some properties of copper ferrocyanide.

Some difficulties in van Laar's theory of the vapour pressures of binary mixtures

Some difficulties in van Laar's theory of the vapour pressures of binary mixtures

A METHOD OF FINDING THE PARTIAL FROM THE TOTAL VAPOR PRESSURES OF BINARY MIXTURES, AND A THEORY OF FRACTIONAL DISTILLATION.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA METHOD OF FINDING THE PARTIAL FROM THE TOTAL VAPOR PRESSURES OF BINARY MIXTURES, AND A THEORY OF FRACTIONAL DISTILLATION.M. A. Rosanoff, C. W. Bacon, and John F. W. SchulzeCite this: J. Am. Chem. Soc. 1914, 36, 10, 1993–2004Publication Date (Print):October 1, 1914Publication History Published online1 May 2002Published inissue 1 October 1914https://doi.org/10.1021/ja02187a002RIGHTS & PERMISSIONSArticle Views239Altmetric-Citations8LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (627 KB) Get e-Alerts Get e-Alerts