Abstract: Titanium-containing slag produced by coal-based DR-EAF smelting was used and enriched by H3PO4 activation roasting and acid leaching, the phase components in the slag included anosovite, pyroxene (glass), Taki stone and spinel. The crystalline transformation of the slag during the roasting process was studied at different roasting temperatures and times, and H3PO4 mass content. The effects of acid leaching temperature, sulfuric acid concentration, mass ratio of liquid to solid and leaching time on the leaching rate of main impurities such as Ca, Mg, Al and Si were examined. The optimal conditions obtained were: roasting temperature 1273 K, roasting time 100 min, H3PO4 content 7.1%, acid leaching temperature 110℃, sulfuric acid concentration 5%, mass ratio of liquid to solid 10:1 and leaching time 120 min. Under the optimal conditions, the content of TiO2 in the slag was raised from 52.54% to 68.31%.

Key words: reduced titanium slag, activation roasting, anosovite, acid leaching, impurity separation

摘要： 以钒钛磁铁矿经煤基直接还原-电炉熔分工艺生产的钛渣为原料，采用磷酸活化焙烧-稀硫酸浸出方法去除杂质提高钛渣品位. 钛渣的物相包括黑钛石、辉石(玻璃相)、塔基洛夫石、镁铝尖晶石等. 考察了磷酸焙烧活化过程中各因素对钛渣晶型转化的影响及稀硫酸浸出过程中各因素对主要杂质(Ca, Mg, Al, Si)浸出的影响，得到优化的工艺条件为：焙烧温度1273 K，焙烧时间100 min，磷酸加入比例7.1%(w)，酸浸温度110℃，硫酸浓度5%(w)，液固质量比10:1，浸出时间120 min，在该条件下钛渣中TiO2含量由52.54%提高至68.31%.

关键词: 还原钛渣, 活化焙烧, 黑钛石, 酸浸, 杂质分离