Particle migration behavior between TiO2 and magnetite under high-temperature oxidative roasting: An experimental and molecular dynamics study

In this paper, the effect of TiO2 on the diffusion and migration behavior between TiO2 and magnetite during high-temperature oxidation roasting was investigated, and the effect of TiO2 on pellet shrinkage behavior, consolidation index (CI), particle growth index (GI), pellet porosity, and uniformity index of particles (UI) was quantified by roasting experiments. It was shown that the presence of TiO2 could hinder the growth of Fe2O3 particles, decrease the CI, and increase the porosity during pellet consolidation. Molecular dynamics was used to study the particle diffusion and migration behavior between TiO2 and magnetite in different mineral forms (Fe2O3, FeTiO3, Fe2TiO5). The atomic migration is mainly influenced by the migration of atoms in the interaction reaction interface. Furthermore, the atomic migration on the surface of the nanoclusters is higher than that inside the nanoparticles, so the surface diffusion of crystalline atoms is the basis of the sintering process.