Ionic liquid mixtures with both different cations and anions (i.e., ternary reciprocal mixtures) are often formally treated as binary mixtures. Mixing laws for binary mixtures are inappropriate for ternary reciprocal mixtures as they do not account for both attractive and repulsive interactions between ions in those liquids. In this work, the viscosity of the [C 2 py], [C 4 py] // Cl, Br ternary reciprocal system (where [C n py] = 1-alkylpyridinium) and all its common-ion binary and unary subsystems was measured over the entire composition range from temperatures close to the liquidus up to about 200 °C. A new viscosity model was proposed to describe the viscosity of ternary reciprocal mixtures more rigorously by accounting for all ion−ion interactions. The robustness of the proposed viscosity model was discussed in comparison with other approaches proposed in the literature. Anomalous discrepancies for the low-temperature viscosity data were observed close to the center of the reciprocal square (consisting of an equimolar mixture of the four pure salts [C 2 py]Cl, [C 2 py]Br, [C 4 py]Cl, and [C 4 py]Br) and could not be accounted for by any of the approaches considered.

Review of principles and limitations of viscosity models for ionic liquids and their mixtures focusing on the use of inappropriate mixing rules for molten salts.

The discovery of new metallic materials is of prime importance for the development of new technologies in many fields such as electronics, aerial and ground transportation as well as construction. These materials require metals which are obtained from various pyrometallurgical processes. Moreover, these materials need to be synthesized under extreme conditions of temperature where liquid solutions are produced and need to be contained. The design and optimization of all these pyrometallurgical processes is a key factor in this development. We present several examples in which computational thermochemistry is used to simulate complex pyrometallurgical processes including the Hall–Heroult process (Al production), the PTVI process (Ni production), and the steel deoxidation from an overall mass balance and energy balance perspective. We also show how computational thermochemistry can assist in the material selection in these extreme operation conditions to select refractory materials in contact with metallic melts. The FactSage thermochemical software and its specialized databases are used to perform these simulations which are proven here to match available data found in the literature.

No abstract

No abstract