Performance of Sulfuric Acid Leaching of Titanium from Titanium-Bearing Electric Furnace Slag

Abstract

<p class="1Body">The sulfuric acid leaching of titanium from titanium-bearing electric furnace slag (TEFS) was investigated under different experimental conditions. In the sulfuric acid leaching process, the M<sub>x</sub>Ti<sub>3-x</sub>O<sub>5</sub>(0≤x≤2) and diopside could react with sulfuric acid. The optimum conditions of sulfuric acid leaching process were particle size at < 0.045mm, sulfuric acid concentration at 90 wt.%, acid/slag mass ratio at 1.6:1, feeding temperature at 120 °C, reaction temperature at 220 °C, reaction time at 120minute, curing at 200°C for 120 minute. The [TiO<sub>2</sub>] concentration of the water leaching was 150 g/L, and leaching temperature at 60℃for 120 minute. Ti extraction could reach 84.29 %. F of titanium-bearing solution was 2.15, and the Ti<sup>3+</sup>/TiO<sub>2</sub> of the titanium-bearing solution was 0.068. The TiO<sub>2</sub> content of the leaching residue was 18.32 wt.%. The main mineral phases of the leaching residue were calcium sulphate, spinel, diopside and little M<sub>x</sub>Ti<sub>3-x</sub>O<sub>5</sub>.</p>