PREPARATION OF HIGH-QUALITY TITANIUM-RICH MATERIAL FROM TITANIUM SLAG WITH HIGH Ca AND Mg CONTENT BY ACTIVATION ROASTING PROCESS

摘要

High-quality titanium-rich material is of significance in the development of titanium industry as it is the main raw material to produce sponge titanium and titanium white using chloride process. Activation roasting of titanium slag with high Ca and Mg contents as adding H_3PO_4 followed by acid leaching was investigated to prepare titanium-rich material. The effects of H_3PO_4 dosage, roasting temperature and time, hydrochloric acid quantity, acid leaching temperature and time on TiO_2 grade and removal of impurities were studied. The results show that after the finely ground titanium slag roasted with 8% H_3PO_4 at 1000°C for 2h, most Mg impurities in anosovite solid solution structure were converted into simple acid-soluble compounds. The impurities such as Ca and Mg obviously decreased when the hydrochloric acid concentration was 20%, leaching at 100 °C for 2h, from which a titanium-rich material containing 82.56% TiO_2 and 1.15% (CaO+MgO) was obtained.