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In this work, physical properties (densities and speeds of sound) for the binary systems {1-propanol, or 2-propanol, or 1-butanol, or 2-butanol, or 1-pentanol + 1-butyl-3-methylimidazolium trifluoromethanesulfonate} were experimentally measured from T = (293.15 to 323.15) K and at atmospheric pressure. These data were used to calculate the apparent molar volume and apparent molar isentropic compression which were fitted to a Redlich–Meyer type equation. This fit was used to obtain the corresponding apparent molar properties at infinite dilution. On the other hand, the osmotic and activity coefficients and vapor pressures of these binary mixtures were also determined at T = 323.15 K using the vapor pressure osmometry technique. The Extended Pitzer model of Archer was employed to correlate the experimental osmotic coefficients. From the parameters obtained in the correlation, the mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures were calculated. 相似文献
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Mark B. Shiflett Daniel J. Kasprzak Christopher P. Junk A. Yokozeki 《The Journal of chemical thermodynamics》2008,40(1):25-31
Carbon dioxide solubility {(vapor + liquid) equilibria: VLE} in ionic liquid, 1-butyl-3-methylimidazolium acetate ([bmim][Ac]), has been measured with a gravimetric microbalance at four isotherms about (283, 298, 323, and 348) K up to about 2 MPa. (Vapor + liquid + liquid) equilibria (VLLE: or liquid–liquid separations) have also been investigated with a volumetric method used in our previous works, since the present analysis of the VLE data using our equation-of-state model has predicted the VLLE at CO2-rich side solutions. The prediction for the VLLE has been confirmed experimentally. CO2 solubilities at the ionic liquid-rich side show extremely unusual behaviors; CO2 dissolves in the ionic liquid to a great degree, but there is hardly any vapor pressure above these mixtures up to about 20 mol% of CO2. It indicates that CO2 may have formed a non-volatile or very low vapor pressure molecular complex with the ionic liquid. The thermodynamic excess properties (enthalpy, entropy, and Gibbs free energy) of the present system do support such a complex formation. We have conducted several other experiments to investigate the complex formation (or chemical reactions), and conclude that a minor chemical reaction occurs but the complex formation is reversible without much degradation of the ionic liquid. 相似文献
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Brown RJ Dyson PJ Ellis DJ Welton T 《Chemical communications (Cambridge, England)》2001,(18):1862-1863
An ambient temperature liquid transition metal carbonyl anion has been prepared in a metathesis reaction between [bmim]Cl ([bmim]+ = 1-butyl-3-methylimidazolium cation) and Na[Co(CO)4]; the ionic liquid catalyses the debromination of 2-bromoketones. 相似文献
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Begoa Gonzlez Noelia Calvar Elena Gmez ngeles Domínguez 《The Journal of chemical thermodynamics》2008,40(8):1274-1281
In this paper, we report experimental densities, dynamic viscosities, and refractive indices and their derived properties of the ternary system (1-butyl-3-methylimidazolium methylsulphate + ethanol + water) at T = 298.15 K and of its binary systems 1-butyl-3-methylimidazolium methylsulphate with ethanol and with water at several temperatures T = (298.15, 313.15, 328.15) K. These physical properties have been measured over the whole composition range and at 0.1 MPa. Excess molar volumes, viscosity deviations, and excess free energy of activation for the binary systems at the abovementioned temperatures, were calculated and fitted to the Redlich–Kister equation to determine the fitting parameters and the root-mean-square deviations and for the ternary systems were calculated and fitted to Cibulka, Singh et al., and Nagata and Sakura equations. The ternary excess properties were predicted from binary contributions using geometrical solution models. Refractive indices were measured from T = 298.15 K over the whole composition range for the binary and ternary systems. The results were used to calculate deviations in the refractive index. 相似文献
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The coexistence curves (T, n), (T, Φ), and (T, Ψ) (n, Φ, and Ψ are the refractive index, volume fraction, and effective volume fraction, respectively) for the ionic liquid microemulsion systems of {polyoxyethylene tert-octylphenyl ether (T-X100) + 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) + cyclohexane} with various molar ratio (ω) of [bmim][BF4] to T-X100 have been determined by measuring refractive indices at a constant pressure in the critical region. The critical temperatures (Tc) and critical volume fraction (Φc) were obtained for the ionic liquid microemulsions. The critical exponents were deduced precisely from the coexistence curves within about 1 K below Tc and the values were consistent with the 3D Ising value. 相似文献
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E. P. Grishina T. V. Vladimirova L. M. Ramenskaya K. S. Shilovskii 《Russian Journal of Electrochemistry》2007,43(2):234-237
Electrochemical oxidation of silver in the 1-butyl-3-methylimidazolium bromide ([BMIm]Br) ionic liquid is studied by cyclic voltammetry, chronopotentiometry, chronoammetry, and gravimetry. Two electrode processes irreversibly proceed on the silver electrode in the potential range studied: the formation of compound [BMIm]+[AgBr2]?, which is soluble in [BMIm]Br, and difficultly soluble AgBr. 相似文献
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E. P. Grishina L. M. Ramenskaya A. M. Pimenova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(11):1883-1886
The physicochemical properties of the low-temperature ionic liquid based on 1-butyl-3-methylimidazolium bromide (BMImBr) and
silver bromide were studied. Differential scanning calorimetry, Fourier transform IR spectroscopy, densimetry, viscometry,
and conductometry measurements were performed to determine the dependences of the parameters under study on the concentration
of AgBr. It was shown that the temperature and concentration behavior of the physicochemical properties of BMImBr-AgBr melts
characterized the interaction between the system components with the formation of complex particles. 相似文献
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Silvia García Marcos Larriba Julián García José S. Torrecilla Francisco Rodríguez 《The Journal of chemical thermodynamics》2011,43(11):1641-1645
The (liquid + liquid) equilibrium (LLE) data for two systems containing heptane, toluene, and 1-methyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide ([mpim][Tf2N]) or 1-allyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([amim][Tf2N]) ionic liquids (ILs) were determined at T = 313.2 K and atmospheric pressure. The effect of a double bond in an alkyl side chain in the imidazolium cation was evaluated in terms of selectivity and extractive capacity. The results show a decrease of the amount of toluene and heptane dissolved in the IL with the allyl group. Thus, the distribution ratios of toluene and heptane of [mpim][Tf2N] IL are higher than those of [amim][Tf2N] IL. On the other hand, the separation factor of the [amim][Tf2N] IL increases comparing to [mpim][Tf2N] IL. The NRTL model was used to correlate satisfactorily the experimental LLE data for the two studied ternary systems. 相似文献
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Juan Pablo Gutierrez Wytze Meindersma André B. de Haan 《The Journal of chemical thermodynamics》2011,43(11):1672-1677
This paper focuses on the study of the solubility behaviour of 1-hexyl-3-methylimidazolium tetracyanoborate [HMIM][TCB] and 1-butyl-3-methylimidazolium tetracyanoborate [BMIM][TCB] in combination with methylcyclohexane and toluene as representatives for non-aromatic and aromatic components. Binary and ternary (liquid + liquid) equilibrium data were collected at three different temperatures and at atmospheric pressure (0.1 MPa). The experimental data were well-correlated with the NRTL and UNIQUAC thermodynamic models; however, the UNIQUAC model gave better predictions than the NRTL, with a root mean square error below 0.97%. The non-aromatic/aromatic selectivities of the ionic liquids make them suitable solvents to be used in extractive distillation processes. 相似文献
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L. M. Ramenskaya E. P. Grishina A. M. Pimenova M. S. Gruzdev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(7):1098-1103
A modified synthesis of 1-butyl-3-methylimidazolium bromide (BMImBr) was suggested and performed, and some physicochemical properties of the product containing 0.64–13.6 wt % water were determined. Water increased the electrical conductivity and decreased the viscosity and melting point of the substance but weakly influenced its density. Water in amounts of 5–8 wt % (45–50 mol %) caused structural changes. The BMImBr · 0.5H2O crystal hydrate was found to be stable thermodynamically. 相似文献
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Víctor H. Alvarez Silvana Mattedi Manuel Martin-Pastor Martin Aznar Miguel Iglesias 《The Journal of chemical thermodynamics》2011,43(7):997-1010
In this work, density and speed of sound data of binary mixtures of an ionic liquid consisting of {2-hydroxy ethylammonium acetate (2-HEAA) + (water, methanol, or ethanol)} have been measured throughout the entire concentration range, from the temperature of (288.15 to 323.15) K at atmospheric pressure. The excess molar volumes, variations of the isentropic compressibility, the apparent molar volume, isentropic apparent molar compressibility, and thermal expansion coefficient were calculated from the experimental data. The excess molar volumes were negative throughout the whole composition range. Compressibility data in combination with low angle X-ray scattering and NMR measurements proved that the presence of micelles formed due to ion pair interaction above a critical concentration of the ionic liquid in the mixtures. The Peng–Robinson equation of state coupled with the Wong–Sandler mixing rule and COSMO–SAC model was used to predict densities and the calculated deviations were lower than 3%, for binary mixtures in all composition range. 相似文献
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Densities and viscosities were determined for binary mixtures of 2,2,2-trifluoroethanol (TFE) and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]), 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) or 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([bmim][NTf2]) over the entire range of composition. The experimental measurements were carried out at temperatures ranging from 278.15 K to 333.15 K, at atmospheric pressure. The densities and viscosities of the pure ionic liquids and their mixtures with TFE were described successfully by an empirical third-order polynomial and by the Vogel–Fulcher–Tammann equation, respectively. In addition, excess molar volumes and viscosity deviations were determined from densities and viscosities of mixtures, respectively, and fitted by using the Redlich–Kister equation. 相似文献
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《The Journal of chemical thermodynamics》2006,38(11):1479-1483
Experimental (liquid + liquid) equilibrium (LLE) data were determined for a ternary system (polyvinylpyrrolidone + MgSO4 + water) at various temperatures of (298.15, 303.15, and 308.15) K. The UNIQAC, modified regular solution, modified Wilson and Chen-NRTL models were used to correlate the experimental tie-line data. The results show that at each temperature, the quality of fitting is better with the Chen-NRTL model. 相似文献
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Experimental isothermal (vapour + liquid) equilibrium (VLE) data are reported for the binary mixture containing 1-butyl-3-methylimidazolium iodide ([bmim]I) + 1-butanol at three temperatures: (353.15, 363.15, and 373.15) K, in the range of 0 to 0.22 liquid mole fraction of [bmim]I. Additionally, refractive index measurements have been performed at three temperatures: (293.15, 298.15 and 308.15) K in the whole composition range. Densities, excess molar volumes, surface tensions and surface tension deviations of the binary mixture were predicted by Lorenz–Lorentz (nD-ρ) mixing rule. Dielectric permittivities and their deviations were evaluated by known equations. (Vapour + liquid) equilibrium data were correlated with Wilson thermodynamic model while refractive index data with the 3-parameters Redlich–Kister equation by means of maximum likelihood method. For the VLE data, the real vapour phase behaviour by virial equation of state was considered. The studied mixture presents S-shaped abatement from the ideality. Refractive index deviations, surface tension deviations and dielectric permittivity deviations are positive, while excess molar volumes are negative at all temperatures and on whole composition range. The VLE data may be used in separation processes design, and the thermophysical properties as key parameters in specific applications. 相似文献
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E. P. Grishina A. M. Pimenova L. M. Ramenskaya O. V. Kraeva 《Russian Journal of Electrochemistry》2008,44(11):1257-1262
The effect of a water impurity (1.8–10 wt %) on the conductivity of the ionic liquid-H2O binary system was studied in a wide temperature range. It was shown that the interaction between components is characteristic of this system, and the molar ratio of components 1: 1 is boundary between the structures of solution and melt. The basic kinetic features of electrochemical reduction of water of the BMImBr-H2O binary system were determined by voltammetry with linear potential sweep. The transfer coefficient for the cathodic process (α = 0.46) and H2O molecule diffusivities were determined depending on the water content ( $ D_{H_2 O} The effect of a water impurity (1.8–10 wt %) on the conductivity of the ionic liquid-H2O binary system was studied in a wide temperature range. It was shown that the interaction between components is characteristic
of this system, and the molar ratio of components 1: 1 is boundary between the structures of solution and melt. The basic
kinetic features of electrochemical reduction of water of the BMImBr-H2O binary system were determined by voltammetry with linear potential sweep. The transfer coefficient for the cathodic process
(α = 0.46) and H2O molecule diffusivities were determined depending on the water content ( = (0.2–1.3) × 10−10 cm2s−1).
Original Russian Text ? E.P. Grishina, A.M. Pimenova, L.M. Ramenskaya, O.V. Kraeva, 2008, published in Elektrokhimiya, 2008,
Vol. 44, No. 11, pp. 1352–1358. 相似文献