Ti₃o₅ and al₂tio₅ crystals flotation characteristics from ti-bearing blast furnace slag: A density functional theory and experimental study

Anosovite crystalline is an ideal mineral for flotation from the Ti-bearing blast furnace (TBBF) slag. Ti₃O₅ crystal and Al₂TiO₅ crystal are two kinds of anosovites, and the Al element significantly affects the electronic structure and flotation performance of anosovite. The floatability of Ti₃O₅ and Al₂TiO₅ crystals were studied by Mulliken populations, energy bands, and density of states (DOS). In addition, the flotation experiment of the two kinds of anosovite crystals (Ti₃O₅ and Al₂TiO₅) was conducted and proved that the density functional theory (DFT) calculation results were accurate. Compared with Ti₃O₅ crystal, the Fermi energy level of Al₂TiO₅ crystal shifts around 2 eV in a negative direction by DOS analysis, which is beneficial to flotation. And Al₂TiO₅ crystal possesses a larger value of bond population, which is 0.41, for Ti-O bonds than Ti₃O₅ crystal and the bond length of Ti-O in Al₂TiO₅ crystal is shorter, therefore Al₂TiO₅ crystal shows a stronger covalency. The changes of the Fermi energy level and the covalency bonds in Al₂TiO₅ crystal both demonstrated that doping the Al component into the Ti₃O₅ crystal was beneficial to improve the flotation effect. Moreover, the Al₂TiO₅ crystal had a higher flotation efficiency compared to the Ti₃O₅ crystal when the dosages of salicylhydroxamic acid (SHA) and sodium oleate were the same. Therefore, both DFT calculation and experiment show that the flotation effect of the Al₂TiO₅ crystal is better than that of the Ti₃O₅ crystal.