Melt Structure of FeO-SiO₂-V₂O₃-TiO₂-MgO Vanadium Slag

In order to clarify the effect of MgO on the structure of vanadium slag with high MgO content, the melt structure of FeO-SiO₂-V₂O₃-TiO₂-MgO was studied by molecular dynamics simulation and experimental characterization. The results show that the main mineral phases in this slag are (Fe, Mg)V₂O₄, (Fe, Mg)₂TiO₄, (Fe, Mg)₂SiO₄, and (MgSiO₃). The average bond lengths of Mg-O, Si-O, Ti-O, V-O, and Fe-O are 2.01 Å, 1.60 Å, 2.05 Å, 1.95 Å, and 2.05 Å, respectively. The bond angle distribution range of ∠O-Si-O and ∠Si-O-Si increases with the increase of FeO/SiO₂ ratio. With the increase of MgO content, Si-O-Si, Si-O-Ti, and Si-O-V connections decrease obviously, Q³ and Q⁴ structural units with high degree of polymerization decrease, and the Network Degree of Depolymerization (NDD) index of vanadium slag increases, indicating that MgO has the function of network depolymerization in vanadium slag.