粗四氯化钛铝粉除钒用TiCl_3浆液制备及应用

Preparation and Application of TiCl_3 Slurry Used in Al-Powder Vanadium Removal of Crude TiCl_4

四氯化钛是生产海绵钛的原料,是钛产业链中的重要中间产品,其中的VOCl_3会影响海绵钛O含量和布氏硬度,因此,粗四氯化钛除钒后方可使用。铝粉除钒是主流除钒工艺,除钒物质是TiCl_3浆液,其质量对精四氯化钛质量影响较大。我国尚未系统掌握TiCl_3浆液制备方法,导致铝粉除钒效果和运行稳定性差。计算了TiCl_3浆液制备过程热力学性质;研究了铝粉悬浮液浓度、氯气通入量、最高温度停留时间、冷凝物处理方式和Cl_2,N_2控制方法等对TiCl_3浆液制备过程及质量的影响,得到了较优工艺参数,开展了稳定试验。结果显示:铝粉先与氯气反应,后与四氯化钛反应生成TiCl_3·0.33AlCl_3;TiCl_3浆液制备较优工艺参数为:铝粉悬浮液浓度1.1%~1.4%(质量分数);氯气加入量按铝粉量控制,Cl_2/Al(质量比)为0.7~1.1;最高温度停留时间6~8 min;氮气压力170~200 kPa,流量为5~7 m^3·h^(-1),氯气压力为120~150 kPa,流量为8~10 m^3·h^(-1)。采用优化工艺参数制备的TiCl_3浆液质量良好,TiCl_3含量8.9%~10.1%,AlCl_3含量3.5%~4.2%,可将粗四氯化钛中VOCl_3含量从0.15%~0.20%降低至0.0003%。

Pure TiCl4 is raw material of titanium sponge production and important intermediate product in titanium industrial chain. VOCl3 has an effect on O content and HB of titanium sponge, so rough TiCl4 must be used after vanadium removal. Removing vanadium by aluminum power was the mainstream technique and vanadium removal material was TiCl3 slurry so its quality had a significant impact on quality of pure TiCI4. TiCl3 slurry preparation method has not been mastered systematically in China, so the effect and operation sta- bility of vanadium removal by aluminum power was poor. Thermodynamic property of preparation process of TICl3 slurry was calculated. Effect of factors （ concentration of aluminum powder suspension, Cl2 amount, maximum temperature retention time, condensate treat- ment and control method of Cl2 and N2 ） on TiCl3 slurry preparation process and quality was researched. The optimum process parame- ters and control method were obtained, and then the stability test was carried out. The result showed that aluminum powder reacted with Cl2 first, then reacted with TICl4, and TiCl3 · 0.33AlCl3 was generated. The optimum process parameters of TiCl3 slurry preparation process were： concentration of aluminum powder suspension was 1.1%- 1.4% （mass fraction） ; amount of Cl2 should be controlled in accordance with aluminum powder amount, Cl2/Al mass ratio was 0.7 - 1.1 ; maximum temperature retention time was 6 - 8 min ; N2 pressure wasl70 -200 kPa, flow rate was 5 -7 m3 ·h-1 , Cl2 pressure was 120 - 150 kPa, flow rate was 8 - 10 m3 ·h-1. TiCl3 slurry quality prepared by optimum process parameters was good, and the TiCl3 content was 8.9%- 10.1% and AlCl3 content was 3.5% 4. 2%. VOCl3 content in crude could be reduced from 0.15%-0.20% to 0. 0003% after vanadium removing operation by TiCl3 slurry.