The effect of B2O3 on the structure and properties of titanium slag melt by molecular dynamics simulations

Synthetic rutile was prepared from titanium slag melt with a low amount of additive (B2O3) and low energy consumption in our previous work. The mechanism by which B2O3 promotes the precipitation of the rutile phase during the cooling and crystallization of titanium slag melt is not clear and needs further theoretical study. The effects of B2O3 on the structure and properties of titanium slag melt were investigated by molecular dynamics simulations in this study. The B2O3 content has a remarkable effect on the coordination environments of B, Ti and Si atoms, while it has no distinct effect on the position of the central peak in the bond length distributions of BOp, TiOm and SiOn polyhedra. As the B2O3 content increases from 0% to 24%, some of the Ti–O bonds in the oxygen connections are replaced by the B–O bonds and the structural strength of the titanium slag melt is reduced. As the B2O3 content increases from 0% to 24%, the self-diffusion coefficients of all ions increase, and their order remains the same. As the B2O3 content increases from 0% to 24%, the viscosity of the titanium slag melt decreases from 0.079 to 0.032 Pa·s. The addition of B2O3 reduces the overall strength, increases the diffusion coefficients and decreases the viscosity of the titanium slag melt. Such changes are conducive to the oxidation of low-valent titanium and to the precipitation of rutile in titanium slag melt. This work may lay the foundation for the efficient preparation of synthetic rutile by adding B2O3 to the titanium slag melt.