Clean separation of vanadium from NaVO3 in NaF-KF-AlF3 molten salt by electrochemical reduction
Clean separation of vanadium from NaVO3 in NaF-KF-AlF3 molten salt by electrochemical reduction
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DOI：
10.1016/j.seppur.2023.123389
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发表时间：
2023-02
影响因子：
8.6
通讯作者：
Yifan Zhang;Xianwei Hu;Jiaxin Yang;Liyu Chen;W. Tao;Liu Fengguo;Zhongning Shi;Zhaowen Wang
中科院分区：
文献类型：
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作者：
Yifan Zhang;Xianwei Hu;Jiaxin Yang;Liyu Chen;W. Tao;Liu Fengguo;Zhongning Shi;Zhaowen Wang
铝钒中间合金是制备高性能钛合金的重要原料。采用循环伏安法（CV）和方波伏安法（SWV）系统研究了NaF-KF-AlF 3熔盐体系中NaVO 3在固态钼和液态铝电极上的电化学行为，着重分析了Al-V金属间化合物的形成机理。结果表明，VO 3-在固体钼电极上的电化学还原是一个多步过程，得到低价钒氧化物（V2 O3）。相比之下，VO 3-在铝液电极上的电化学还原为V2 O3是一步完成的，且由于铝液电极的去极化作用，沉积电位比钼电极上的正.此外，通过恒电位电解，在液态铝电极上获得了Al-V金属间化合物。VO 3-在液态铝电极上的还原过程描述为：电化学过程由VO 3-直接电还原为V2 O3开始，在电化学和铝热还原的共同作用下，V2 O3进一步转化为Al-V金属间化合物，其中后者起主导作用。
Aluminum-vanadium intermediate alloy is a significant raw material for the fabrication of high-performance titanium alloys. In the present study, the electrochemical behavior of NaVO3on a solid molybdenum and liquid aluminum electrode is systematically investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV) in the NaF-KF-AlF3molten salt and the formation mechanism of Al-V intermetallic compounds is emphatically analyzed. The results show that the electrochemical reduction of VO3−on the solid molybdenum electrode is a multi-step process and low-valence vanadium oxide (V2O3) is obtained. In contrast, the electrochemical reduction of VO3−to V2O3on liquid aluminum electrode is through one-step process and the deposition potential is more positive than that on molybdenum electrode owing to the depolarization effect of the liquid aluminum electrode. In addition, Al-V intermetallic compounds are obtained on the liquid aluminum electrode by potentiostatic electrolysis. The reduction process of VO3−on the liquid aluminum electrode is described as: the electrochemical process is started by the direct electro-reduction of VO3−to V2O3, which is further converted to Al-V intermetallic compounds under the combined effect of electrochemical and aluminothermic reduction, with the latter playing a dominant role.