V. A. Khokhlov

Specific features of the interaction of α- and γ-modifications of Al2O3 with carbonate and carbonate-chloride melts

Data on reactivities of α- and γ-Al2O3 finely dispersed powders in a melted carbonate eutectic (Li2CO3–Na2CO3–K2CO3)eut and carbonate-chloride mixture 0.72(Li2CO3–Na2CO3–K2CO3)eut–0.28NaCl were obtained. The methods of synchronous thermal and X-ray phase analyses and Raman spectroscopy confirmed that, in contrast to γ-Al2O3, α-Al2O3 does not chemically interact with the melted carbonate eutectic and carbonate-chloride mixture (Li2CO3–Na2CO3–K2CO3)eut–NaCl can be recommended as a thickening agent for a carbonate fuel cell.

Raman spectroscopy study of the phase transitions in rare-earth metal trichlorides

The structures of crystalline (over a wide temperature range) and molten rare-earth metal-LnCl3 (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy) trichlorides are comprehensively studied by Raman spectroscopy.

Thermodynamic characteristics of samarium and europium chlorides in molten alkali metal chlorides

Abstract The formal standard redox potentials of samarium (III)/(II) (E*Sm3+/ Sm2+) and europium (III)/(II) (E*Eu3+ /Eu2+) in molten alkali metal chlorides were measured potentiometrically against a reference chlorine electrode. The Gibbs energy changes and equilibrium constants for the reaction LnCl2(I) + ½ Cl2(g) ⇔ LnCl3(I) were calculated for the salt systems studied. The effect of the cationic composition of the melt-solvent on the above thermodynamic characteristics is also reported.

Anomalous Thermal Conductivity of Crystalline Alkali Halides Close to Their Melting Point

Abstract The thermal conductivity of crystalline alkali halides MX (M = Li, Na, K, Rb, and Cs; X = C1, Br, and I) close to their melting point has been measured by the steady-state coaxial-cylinders method. It was found to change anomalously as the temperature varied. A minimum of the thermal conduc-tivity at a characteristic temperature depends on the ionic composition of the crystal. This effect is ascribed to the formation of cooperating defects in the melting lattice. An expression relating the thermal conductivity of the ionic crystal near the melting point to the concentration of these defects is proposed.

Electrical conductivity of low-temperature NaCl-KCl-ZrCl4 melts

The dependences of the electrical conductivity of NaCl-KCl-ZrCl4 molten mixtures with a molar ratio NaCl : KCl = 8 : 29 on the temperature (temperature range of 300–540°C) and the ZrCl4 concentration (54.3–75.2 mol %) have been measured for the first time using unique cells.

Ultrasound velocity and adiabatic compressibility of molten GdCl3 and its solutions in potassium chloride

The ultrasound velocity in the melts of gadolinium chloride and its mixtures with potassium chloride is measured as a function of the temperature and composition, and their adiabatic compressibilities are calculated. A relation is established between the relative deviations of these properties from their values for hypothetic ideal solutions.

Ultrasound velocity and adiabatic compressibility of LaCl3 + MCl (M = Li, Na, K, Rb, and Cs) melts

The ultrasound velocity in binary LaCl3 + MCl (M = Li, Na, K, Rb, and Cs) melts is measured, and their adiabatic compressibility is calculated as a function of temperature and composition. A relation is established between the relative deviations of these properties from their values for hypothetic ideal salt mixtures, on the one hand, and the ionic potentials of the alkali-metal cations, on the other.

Isothermal compressibility, isochoric heat capacity, and intrinsic pressure of KCl-NdCl3 melts

The temperature dependences of the isothermal compressibility, isochoric heat capacity, intrinsic pressure, expansion work, number of vibrational degrees of freedom, and parameter a of KCl-NdCl3 melts are calculated from experimental data on the ultrasound velocity, density, and heat capacity of these melts.

On the classification of molten salt electrolytes

The physicochemical and electrochemical properties of various types of real molten salt electrolytes are comprehensively studied, and they are classified according to the temperature and concentration dependences of their physical and electrochemical properties, which are determined by the type of chemical bond between particles, complexing, and the contribution of electron charge transfer.

The Molar Volume of Molten Mixtures of MCl-LnCl2 (M = Alkali Metals, Ln = Lanthanoides)

Empirical equations for the density and molar volume of molten binary mixtures of MCl-LnCl2 and MCl-MeCl2 (M = alkali metals; Ln = lanthanoides; Me = Ca, Sr, Ba) based on the density of individual components are suggested. The equations, taking into account the deviations of the molar volumes from their additive values, are applicable to all binary systems involving known rare earth dichlorides.