Binary ionic liquid mixtures

Abstract Understanding the ways in which the constituents of ionic liquids, i.e. the type of cation, its substitution, and the type of anion chosen, interact with reactants is prerequisite to deliberately designing an ionic liquid solvent with optimum performance. Several approaches, including physico-chemical and spectroscopic measurements and computational studies of binary ionic liquid-substrate mixtures have been presented that investigate the strength of interactions. 

An application to one binary mixture of a volatile electrolyte and water will illustrate the choice of parameters H and K, an approach is proposed to represent the vapor-liquid equilibrium in the whole range of concentration. Ternary mixtures with one acid and one base lead to the formation of salts and high ionic strengths can be reached. There, it was found useful to take into account... 

Zafarani-Moattar, M.T. and Shekaari, H. Volumetric and speed of sound of ionic liquid, l-butyl-3-methylimidazolium hexafluorophosphate with acetonitrile and methanol at T = (298.15 to 318.15) K, /. Chem., Eng. Data, 50,1694,2005. Wang, J. et al.. Excess molar volumes and excess logarithm viscosities for binary mixtures of the ionic liquid l-butyl-3-methylimidazolium hexafluorophosphate with some organic solvents, /. Solution Chem., 34, 585, 2005. 

Sirieix-Plenet, ]., Gaillon, L., and Letellier, R, Behaviour of a binary solvent mixture constituted by an amphiphilic ionic liquid, l-decyl-3-methylimidazolium bromide and water. Potentiometric and conductimetric studies, Talanta, 62, 979,... 

Heintz, A., Lehman, J.K., and Wertz, Ch., Thermodynamic properties of mixtures containing ionic liquids. 3. Liquid-liquid equilibria of binary mixtures of l-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide with propan-l-ol, butan-l-ol, and pentan-l-ol, /. Chem. Eng. Data, 48, 472, 2003. 

Verevkin, S.R et al.. Thermodynamic properties of mixtures containing ionic liquids. Vapor pressures and activity coefficients of n-alcohols and benzene in binary mixtures with l-methyl-3-butyl-imidazolium bis(trifluoromethyl-sulfonyl)imide. Fluid Phase Equilib., 236, 222, 2005. 

Binary mixtures of ionic liquids as high-selecfivify... 

Baltazar, Q.Q., Leininger, S.K., and Anderson, J.L., Binary ionic liquid mixtures as gas chromatography stationary phases for improving the separation selectivity of alcohols and aromatics compounds, /. Chromatogr. A., 1182, 119-127, 2008. 

Fletcher, K. A., Baker, S. N., Baker, G. A., and Pandey, S., Probing solute and solvent interactions within binary ionic liquid mixtures. New. Chem., 27,1706-1712, 2003. 

Consider, for instance, the electrical conductance of fused CdClj and KCl mixtures. If the equivalent conductivity of the mixtures (at a fixed temperature) were given by a simple additivity relation, then a linear variation of equivalent conductivity with the mole fraction of KCl should be observed (dashed line in Fig. 5.53). The straight line should run from the equivalent conductivity of pure liquid CdClj at a particular temperature to that of pure liquid KCl at the same temperature. Some binary mixtures of single ionic liquids do indeed exhibit the simple additivity implied by the dashed line of Fig. 5.53. 

Heintz A, Klasen D, Lehmann J K. Excess molar volumes and viscosities of binary mixtures of methanol and the ionic liquid 4-methyl-N-butylpyridinium tetrafluoroborate at 25, 40, and 50 °C. J. Solution Chem. 2002. 31, 467-476. 

In this study we restrict our consideration by a class of ionic liquids that can be properly described based on the classical multicomponent models of charged and neutral particles. The simplest nontrivial example is a binary mixture of positive and negative particles disposed in a medium with dielectric constant e that is widely used for the description of molten salts [4-6], More complicated cases can be related to ionic solutions being neutral multicomponent systems formed by a solute of positive and negative ions immersed in a neutral solvent. This kind of systems widely varies in complexity [7], ranging from electrolyte solutions where cations and anions have a comparable size and charge, to highly asymmetric macromolecular ionic liquids in which macroions (polymers, micelles, proteins, etc) and microscopic counterions coexist. Thus, the importance of this system in many theoretical and applied fields is out of any doubt. 

The overall conclusion from these studies is that, in spite of essential progress in understanding the collective behavior of ionic liquids, many problems are still open for further work. In particular, it is important to perform an additional study of a binary mixture of neutral particles with antiferromagnetic ... 

Heintz, A., Lehmann, K.J., and Wertz, C. Thermodynamic properties of mixtures containing Ionic Liquids 3. Liquid-Liquid Equilibria of Binary Mixtures of lethyl-3-methylimidazolium Bistrifluoromethylsulfonyl)imide with propanol, butanol, and pen-tanol. J. Chem. Eng. Data, 2003, 48, p. 472-4. 

Wagner, M., Stanga, O., and Schroer, W. The liquid-liquid coexistence of binary mixtures of the roomtemperature ionic liquid 1 -methyl-3 -hexylimidazolium tetrafluorid with alcohols. Phys. Chem. Chem. Phys., 2004, 6, p. 4421-31. 

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