关键词: 碳热还原, 含钛高炉渣, 三氧化二铁, 形核长大, 富集

Abstract: Titanium is a very kind of important and useful metal, which is widely used in the aerospace and chemical industries. By the beneficiation process of Panzhihua Iron and Steel Co., titanomagnetite concentrates and ilmenite concentrates are produced. The titanomagnetite concentrates are widely used as the raw materials for the blast furnace process now, by which most of the iron and vanadium can be reduced into the hot metal. However, almost all of the titanium remain in the slag to form the high titanium bearing slag, which contains about 21wt%?25wt% of TiO2. In the present study, the carbothermic reduction experiments of titanium-bearing blast furnace slag were carried out in argon atmosphere at high temperature. The main subject was to separate the reduction product TiC from the remaining slag considering the small grain size of the produced TiC during the carbothermic reduction process. The influences of adding Fe2O3 on the reaction process were studied by XRD and SEM?EDS. The results showed that during the carbothermic reduction process, it can be known that the changes of standard Gibbs free energy was negative at 1773 K. Adding a small amount of Fe2O3 into the raw material was beneficial for the dispersion of Fe phase in the liquid slag as well as the growth of TiC particle size. When the content of Fe2O3 was increased to 5wt%, TiC which grows attached to the Fe phase will settle down and concentrate at the bottom of the reduction product to achieve the preliminary enrichment of TiC. This finding may contribute to the seperation and extraction of titanium from titanium bearing blast furnace slag in the form of TiC phase.

Key words: carbothermic reduction, titanium-bearing blast furnace slag, Fe2O3, nucleation and growth, enrichment