真空碳热还原-酸浸含钛高炉渣制备TiC

中国超过50％钛资源在高炉冶炼过程中进入炉渣,渣中TiO2的质量分数高达20％～30％,是一种高附加值二次资源,但在对该资源综合利用过程中,始终未能解决经济提取、硅钛难分,二次污染严重等问题.在热力学理论指导下进行真空碳热还原-酸浸联合工艺处理含钛高炉渣制备TiC研究.研究表明,碳热还原温度越高或相同温度下真空度越高越有利于炉渣中各成分还原;随着真空度增加碳热还原温度要求降低;当温度达到1 573K,真空度为1 Pa,可将SiO2还原得到具有高蒸气压的SiO、MgO被还原为Mg蒸气而离开体系,可实现渣中硅镁与钛彻底分离;真空碳热还原含钛高炉渣制备TiC的最佳条件:还原温度1673 K,炉渣粒度75μm占80％,渣碳质量比100∶38.

Preparation of TiC using the blast furnace slag bearing titanium by carbothermal reduction in vacuum and acid leacing

More than 50％ titanium resource is concentrated in the slag during extracting Fe by blast furnace process.Blast furnace slag,containing 20％-30％ titanium dioxide,is a kind of the valuable secondary resources.However,there are some problems in the process of comprehensive utilization of the titanium resources.Such as high cost,difficult separation of titania and sinica,serious second pollution and so on.Preparation of TiC from the blast furnace slag bearing titanium by carbothermal reduction in vacuum and acid leaching process based on the thermodynamics results was researched.The results show that the higher the carbon thermal reduction temperature or the vacuum at the same temperature,the more helpful it will be to slag reduction.The reduction temperature decreases with increasing of the vacuum degree.SiO2 and MgO can be reduced to SiO and Mg with high vapor pressure at 1 573 K and 1 Pa which can leave from the slag systerm.The optimum conditions for preparation of TiC using the blast furnace slag bearing titanium by carbothermal reduction in vacuum are 80 ％ slag with size of 75μm,temperature of 1 673 K,the mass ratio of the slag and carbon is 100 ∶ 38.