高氯高铁型四氯化钛除钒尾渣焙烧提钒工艺研究

针对氯化法生产钛白粉工艺中除钒固体废弃物难以有效再利用的问题,研究了除钒尾渣钠化焙烧?水浸脱氯提钒工艺中Na2 CO3添加量、焙烧时间及温度对钒浸出率的影响,实现高氯高铁型四氯化钛除钒尾渣资源的二次利用.结果表明,采用液固比10 mL/g的水洗工艺,可大幅降低尾渣中NaCl对沉钒率的影响;水洗后的除钒尾渣在Na2 CO...

Vanadium Extraction by Roasting from High Chlorine-and-Iron Titanium Tetrachloride Tailings After Vanadium Removal

Due to being difficult to be reused effectively during the production of titanium dioxide by chlorination, the solid waste after vanadium removal was treated by the process consisting of sodium roasting and aqueous leaching for dechlorination and vanadium extraction, and the effects of adding amount of Na₂CO₃, roasting time and temperature on vanadium leaching rate were investigated for realizing the secondary utilization of vanadium removal tailings resources of titanium tetrachloride with high contents of chlorine and iron. The results show that the influence of NaCl in tailings on vanadium precipitation rate can be greatly reduced by using water washing process with liquid-solid ratio of 10 mL/g; vanadium removal tailings after water washing are roasted at 850 ℃ for 2 h by adding Na₂CO₃ at an amount of 20%, and then subjected to aqueous leaching, resulting in a vanadium leaching rate reaching 88.19%; by adding (NH4)₂SO₄ into the leaching solution with NH₄⁺/V molar ratio of 2.5∶1, NH₄VO₃ can be generated. And then after drying and roasting, the powdered V₂O₅ can be obtained with the grade over 99.7%. It is shown the recovery rate of vanadium from the whole process is 81.38%.