Migration and Enrichment Behaviors of Ca and Mg Elements during Cooling and Crystallization of Boron-Bearing Titanium Slag Melt

Abstract

Synthetic rutile was prepared from titanium slag melt with low energy consumption and a small amount of additive (B2O3) in our previous work. The modification mechanism of titanium slag was not clear enough. The migration and enrichment behaviors of Ca and Mg elements during cooling and crystallization of boron-bearing titanium slag melt were characterized by XRF, FESEM, EMPA, and XPS. Results show that when additive (B2O3) is added, Ti elements are migrated and enriched in the area to generate rutile, while Ca, Mg, and B elements are migrated and enriched in another area to generate borate. With the additive (B2O3) amount increased, Ca and Mg element migration is complete and more thorough. Additive (B2O3) promotes rutile formation and inhibits the formation of anosovite during cooling and crystallization of titanium slag melt. With the additive (B2O3) amount increasing from 0% to 6%, the proportion of Ti3+ in the modified titanium slag reduces from 9.15% to 0%, and the proportion of Ti4+ increases from 90.85% to 100% under the same cooling and crystallization condition. The result will lay the foundation for the efficient preparation of synthetic rutile by adding B2O3 to the titanium slag melt.