China Nonferrous Metallurgy

Vanadium titanium magnetite produces a large amount of smelting slag in the blast furnace smelting process, and the titanium content of the smelting slag reaches 20%~30%. The resource utilization of vanadium titanium magnetite or titanium resources in the smelting slag has always been an important research topic. In the present work, we referred to the titanium leaching-solvent extraction process. In view of the problems of the existing extraction system, such as long extraction equilibrium time, low titanium extraction rate, equipment corrosion, difficulty in separating aqueous phase and organic phase, the mechanically activated vanadium titanium magnetite blast furnace slag is first leached with hydrochloric acid, then, a synergistic extraction system consisting of tributyl phosphate (TBP) and di (2-ethylhexyl) phosphoric acid (P204) was used (with sulfonated kerosene as the diluent) to extract titanium from the leaching solution. The experiment investigated the effects of the total concentration of extractant, extraction temperature, extraction ratio (O/A), the ratio of extractant TBP to P204, and the concentration of chloride ions on the titanium extraction rate. At the same time, the slope method was employed to preliminarily explore the extraction mechanism. The following conclusions were obtained: under optimal extraction conditions such as chloride ion concentration of 8mol/L, at the ratio of extractants TBP∶P204=1∶4, extraction time 20 minutes, extraction temperature 30℃, extraction ratio (O/A) 1∶1, the titanium extraction rate can reach over 98%. The slope method study on the extraction mechanism shows that the composition of the extract may be [TiOCl₂][HA]₂[HB]₂, and its extraction chemical reaction equation can be rewritten as:TiO²⁺+2HA+2HB+2Cl^-→[TiOCl₂][HA]₂[HB]₂.