Modeling of thermodynamic and physical properties of oxide and sulfide solutions for applications in metallurgy and materials science

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Oxide solutions encompass metallurgical slags, magmas and lavas, many important minerals which make up most of the Earth crust, ceramics, glasses, etc. Sulfide ores and the molten sulfide phase called matte are of primary importance for smelting of many metals. Accurate modeling of various properties of solid and liquid solutions is essential in process simulation for a very wide range of applications including primary metals extraction, glass technology, conventional and functional ceramics, high tech materials, combustion, environmental science, corrosion control, waste management, etc.***     *Most oxides and sulfides that we encounter are multicomponent solutions. We need to know the thermodynamic and physical properties of these solutions as functions of temperature, pressure and composition to understand what is going on in the inaccessible depths of the Earth, how planets and nebulae form, and to develop cost-effective, environmentally-friendly and energy-efficient production processes and novel high-tech materials. However, it is essentially impossible to study experimentally the thermodynamic and physical properties of all important solutions because the necessary amount of work increases exponentially with the number of components. Hence, we need to develop a model for each particular solution that is calibrated based on available data and can then accurately predict the properties of the multicomponent solution.***Modeling of oxide and sulfide solutions is a challenging task. Oxide and particularly silicate solutions are quite extraordinary in their ability to incorporate many different cations by adjusting the structure. Complex oxide solutions often have several sublattices and reveal a strong tendency to inter- and intra-sublattice short-range ordering, which is responsible for specific physical properties. For example, the distribution of cations and defects between different sublattices defines volumetric, electrical and magnetic properties of ceramic phases; short-range ordering strongly affects viscosity and thermodynamic properties of liquid slags and mattes. This structural complexity must be reflected in the models. Unless the mathematical model for a particular property is based upon a realistic physical model, interpolations, extrapolations, and predictions have little chance of success.***     *The project will involve the development and testing of new models for oxide and sulfide solutions that relate microscopic structural features to macroscopic thermodynamic behavior. The goal is to model the major solutions that are important for both the Earth science and a wide range of industries. The correlations between different properties will be established with a view to using the structural information obtained from the modeling of one property (particularly from the modeling of thermodynamic properties) to facilitate modeling of other properties.