Some thermodynamic and transport properties of lithium salts in mixed aprotic solvents and the effect of water on such properties

In a continuing study on the optimization of the electrolyte medium for high-energy lithium batteries, volumes, heat capacities, and specific conductivities of LiClO4 and LiBr were measured in mixtures of γ-butyrolactone (BUTY) and 1,2-dimethoxyethane (DME) and of propylene carbonate (PC) and BUTY. These results are compared with those of the electrolytes in the pure solvents. Phase diagrams are also reported when appropriate. The effect of addition of water to these binary and ternary systems was investigated with the same techniques. The mixtures DME–BUTY, PC–DME, DME–H2O, and BUTY–H2O are typical of mixtures of aprotic solvents and mixtures of aprotic solvents and water. The electrolytes at high concentrations in aprotic solvents of low dielectric constants are largely associated. The medium still conducts electrolytically since the ion pairs are in a state that resembles to a large extent that of a molten salt. With some systems at high concentration, stable solvates persist in the solution medium, as evidenced mostly by heat capacities, and are in equilibrium with either the excess solvent or unsolvated molten salts. In mixed solvents, the properties of electrolytes can largely be predicted from the binary systems and by the coexistence of these solvates. The properties of water in DME, BUTY, or mixtures of the two solvents are modified significantly in the presence of LiBr but only slightly with LiClO4. These specific interactions, which affect the heat capacities much more than the volumes and which are especially large with the system LiBr–DME, could be responsible for the decrease in reactivity of water with lithium metal in an aprotic medium in the presence of certain electrolytes. Key words: LiClO4, LiBr, γ-butyrolactone, dimethoxyethane, propylene carbonate, lithium battery, aprotic solvent, water, association, solvates, solid–liquid phase diagrams, volumes, heat capacities, specific conductivities.

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Dielectric and Excess Dielectric Constants of Acetonitrile + Butyl Amine, + Ethylamine, and + Methylamine at 303, 313, and 323 K

Journal of Chemistry ◽

10.1155/2013/687106 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Ch. V. V. Ramana ◽

A. B. V. Kiran Kumar ◽

M. Ashok Kumar ◽

M. K. Moodley

Keyword(s):

Dielectric Constant ◽

Intermolecular Interactions ◽

Mole Fraction ◽

Entire Range ◽

Binary Systems ◽

Mixed Solvents ◽

Dielectric Constants ◽

Complete Mole ◽

Butyl Amine ◽

Mole Fraction Range

The dielectric constants and excess dielectric constants of the binary systems: acetonitrile + butyl amine, + ethylamine and + methylamine have been studied at 303, 313, and 323 K temperatures and over the complete mole fraction range. The dielectric constants for these mixtures were measured using a microcontroller based system. The results are positive over the entire range of composition. Symmetrical curves were observed for the systems in which the maximum occurs approximately at 0.7-mole fraction of acetonitrile. The results are discussed in terms of intermolecular interactions. The investigation of dielectric constant of mixed solvents bearing amines aims at better comprehension of their biological, chemical, pharmaceutical, technological, and laboratory applications.

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Excess properties of the binary liquid systems dimethylsulfoxide + isopropanol and propylene carbonate + isopropanol

Canadian Journal of Chemistry ◽

10.1139/v89-166 ◽

1989 ◽

Vol 67 (6) ◽

pp. 1105-1108 ◽

Cited By ~ 49

Author(s):

George Ritzoulis

Keyword(s):

Dielectric Constant ◽

Propylene Carbonate ◽

Binary Systems ◽

Correlation Factor ◽

Dielectric Constants ◽

Excess Properties ◽

Binary Solvent ◽

Solvent Mixtures ◽

Liquid Systems ◽

Mole Fraction Range

The dielectric constants, viscosities, densities, and refractive indices of the binary solvent mixtures dimethylsulfoxide–isopropanol and propylene carbonate–isopropanol were measured at 25, 30, and 35 °C over the entire mole fraction range. Excess dielectric constant, excess molar polarization, and excess viscosity were calculated. For both binary systems the variation of the Kirkwood correlation factor has been examined. Keywords: propylene carbonate, acetonitrile, correlation factor, excess properties, dielectric constant.

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Phase diagrams, molar volumes, heat capacities, conductivities and viscosities of some lithium salts in aprotic solvents

Journal of Electroanalytical Chemistry ◽

10.1016/0022-0728(93)80368-r ◽

1993 ◽

Vol 355 (1-2) ◽

pp. 277-296 ◽

Cited By ~ 16

Author(s):

Gérald Perron ◽

Lorraine Couture ◽

Daniel Lambert ◽

Jacques E. Desnoyers

Keyword(s):

Phase Diagrams ◽

Heat Capacities ◽

Lithium Salts ◽

Aprotic Solvents ◽

Molar Volumes

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Calculation of phase diagrams and thermodynamic properties of 14 additive and reciprocal ternary systems containing Li2CO3, Na2CO3, K2CO3, Li2SO4, Na2SO4, K2SO4, LiOH, NaOH, and KOH

Canadian Journal of Chemistry ◽

10.1139/v84-078 ◽

1984 ◽

Vol 62 (3) ◽

pp. 457-474 ◽

Cited By ~ 19

Author(s):

A. D. Pelton ◽

C. W. Bale ◽

P. L. Lin

Keyword(s):

Phase Diagram ◽

Thermodynamic Properties ◽

Molten Salt ◽

Phase Diagrams ◽

Binary Systems ◽

Ternary Phase ◽

Ternary Phase Diagram ◽

Ternary Systems ◽

Maximum Error ◽

Critical Assessment

Phase diagrams and thermodynamic properties of five additive molten salt ternary systems and nine reciprocal molten salt ternary systems containing the ions Li+, Na+, [Formula: see text], OH− are calculated from the thermodynamic properties of their binary subsystems which were obtained previously by a critical assessment of the thermodynamic data and the phase diagrams in these binary systems. Thermodynamic properties of ternary liquid phases are estimated from the binary properties by means of the Conformal Ionic Solution Theory. The ternary phase diagrams are then calculated from these thermodynamic properties by means of computer programs designed for the purpose. It is found that a ternary phase diagram can generally be calculated in this way with a maximum error about twice that of the maximum error in the binary phase diagrams upon which the calculations are based. If, in addition, some reliable ternary phase diagram measurements are available, these can be used to obtain small ternary correction terms. In this way, ternary phase diagram measurements can be smoothed and the isotherms drawn in a thermodynamically correct way. The thermodynamic approach permits experimental data to be critically assessed in the light of thermodynamic principles and accepted solution models. A critical assessment of error limits on all the calculated ternary diagrams is made, and suggestions as to which composition regions merit further experimental study are given.

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Solubilities of the silver halides in propylene carbonate mixtures with bis(trifluoroethyl)sulfite

Canadian Journal of Chemistry ◽

10.1139/v77-343 ◽

1977 ◽

Vol 55 (13) ◽

pp. 2499-2503 ◽

Cited By ~ 1

Author(s):

Mark Salomon

Keyword(s):

Propylene Carbonate ◽

Inductive Effect ◽

Mixed Solvents ◽

Chemical Properties ◽

Silver Ions ◽

Halide Ions ◽

Silver Halides

The complex solubilities of AgCl, AgBr, and AgI have been measured in several mixed solvents containing propylene carbonate and bis(trifluoroethyl)sulfite. The results indicate that a large inductive effect destabilizes the solvation of silver ions whereas the halide ions appear to be stabilized by coordination with the sulfinyl sulfur. Several physio-chemical properties of pure bis(trifluoroethyl)sulfite are reported.

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LIMITING CONDUCTANCE OF LYONIUM AND LYATE IONS

Canadian Journal of Chemistry ◽

10.1139/v59-024 ◽

1959 ◽

Vol 37 (1) ◽

pp. 173-177 ◽

Cited By ~ 2

Author(s):

Martin Kilpatrick

Keyword(s):

Mixed Solvents ◽

Direct Determination ◽

Solvent Mixture ◽

Dielectric Constants ◽

Proton Mobility ◽

Anhydrous Hydrogen Fluoride ◽

Ice Leads ◽

Hydrogen Bonded Systems ◽

High Dielectric ◽

Strong Acids

The problem of proton mobility has been considered in H2O–CH3OH, H2O–D2O, and H2O–H2O2 solvents from the current viewpoint of the mechanism of proton mobility for aqueous solutions. Mixed solvents are more complicated in that one must consider the relative basicity and acidity of the species competing for the protons. It is concluded that for dilute solutions of HClO4, where water is replaced by hydrogen peroxide, the decrease in equivalent conductance relative to that of KCl in the same solvent mixture is due to the partial elimination of the proton transfer process.For highly acidic non-aqueous solvents of high dielectric constants such as HF, HCN, and HCOOH, the problem of the weakness of the usual "strong" acids of aqueous solution makes a direct determination of the limiting equivalent conductances difficult. In the case of anhydrous hydrogen fluoride the available experimental evidence indicates that the limiting conductance of the lyonium ion is approximately the same as that of the potassium ion but the lyate ion has a higher limiting conductance than other stable anions.The higher proton mobility in ice leads one to expect that hydrogen-bonded systems may be found where the conductivity may approach that of electronic semiconductors.

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The behaviour of electrolytes in mixed solvents. Part I.—The free energies and heat contents of hydrogen chloride in water—Ethyl alcohol solutions

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1929.0196 ◽

1929 ◽

Vol 125 (799) ◽

pp. 694-712 ◽

Cited By ~ 9

Keyword(s):

Hydrogen Chloride ◽

Electric Fields ◽

Mixed Solvents ◽

Dielectric Constants ◽

Free Energies ◽

Dissolved Ions ◽

Uniform Medium ◽

The Mean ◽

Solvent Molecules ◽

Water Alcohol

Previous studies on the effect of a change of medium on tire properties of dissolved electrolytes have aimed at correlating the behaviour of the electrolyte with the mean physical properties, e. g ., dielectric constants, of the medium. While this approach may be justified in the case of solvents containing molecules of only one kind, it is not sufficient to regard a mixed solvent as a uniform medium affecting the dissolved ions solely through the effect of its dielectric constant on the electric forces between them. For the electric fields of ions exert a differential attraction on molecules possessing different degrees of polarisability and since tire more polarisable molecules must tend to congregate round the ions, the properties of the latter cannot depend solely on tire mean properties of tire medium. Studies on the behaviour of ions in such cases will throw light on the interaction between ions and solvent molecules. The present paper gives tire results of measurements of the free energies and heat contents of hydrogen chloride in water-alcohol solutions, obtained by determining the electromotive forces of cells of the type:— H 2 ( g ) | HCl ( m ), AgCl ( s ) | Ag water-alcohol

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Electron-transfer reactions in non-aqueous media. VII. Reduction of CoF(NH3)52+ and Co(HCOO)(NH3)52+ by copper(I) in dimethyl sulfoxide-water mixtures

Australian Journal of Chemistry ◽

10.1071/ch9831923 ◽

1983 ◽

Vol 36 (10) ◽

pp. 1923 ◽

Cited By ~ 2

Author(s):

JMB Harrowfield ◽

L Spiccia ◽

DW Watts

Keyword(s):

Electron Transfer ◽

Dimethyl Sulfoxide ◽

Aqueous Media ◽

Mixed Solvents ◽

Transfer Reactions ◽

Aprotic Solvents ◽

Aqueous Mixtures ◽

Electron Transfer Reactions ◽

Dipolar Aprotic Solvents ◽

Sphere Mechanism

Previous work on the reduction of a series of cobalt(III) complexes by iron(II) in dipolar aprotic solvents and in aqueous mixtures has been extended to reduction by copper(I). The greater stability of copper(I) to disproportionation in these media has permitted the study of the reduction of CoF(NH3)52+ and Co(HCOO)(NH3)52+ in range of solvents over a number of temperatures with a precision not possible in previous studies in water. The results are consistent with an inner-sphere mechanism in which the copper(I) reductant is preferentially solvated by dimethyl sulfoxide to the exclusion of water in mixed solvents.

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