Thermodynamic modeling of the Ni–S system

Abstract

Abstract A thorough review and critical evaluation of phase equilibria and thermodynamic data of the nickel – sulfur binary system at 1 bar pressure has been made over the entire composition range for temperatures from 25°C to above the liquidus. The Gibbs energies of nine phases have been modeled, and optimized model parameters have been obtained which reproduce all data simultaneously within experimental error limits. For the liquid phase, the recently extended modified quasichemical model is applied. Two-sublattice models within the framework of the Compound Energy Formalism are used for the high-temperature heazlewoodite and monosulfide pyrrhotite solutions. The Gibbs energies of six stoichiometric compounds are also modeled.