Reduction of titanium and other metal oxides using electrodeoxidation
Reduction of titanium and other metal oxides using electrodeoxidation
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DOI：
10.1179/026708304225012242
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发表时间：
2004-03-01
影响因子：
1.8
通讯作者：
Chen, GZ
中科院分区：
文献类型：
--
作者：
Fray, DJ;Chen, GZ
许多反应性和难熔金属目前在工业上通过使用更反应性的金属还原其化合物（包括氧化物）来生产。在某些情况下，在金属中存在大量氧溶解度的情况下，首先通过碳氯化然后通过还原除去氧。钛和锆是由镁还原挥发性的四氯化物制成的。该方法基本上由两个还原步骤组成：将氯化镁还原为镁金属，然后还原金属化合物;这使得整个还原过程相对昂贵。电脱氧非常简单，因为要还原的氧化物在熔融碱土金属氯化物中呈阴极。通过施加低于盐的分解电势的电压，已经发现氧的电离是主要的阴极反应，而不是碱土金属沉积。在实验室中，该技术已被应用于将大量金属氧化物还原为金属，包括钛、锆、铬、铌、钽、铀和镍。此外，当使用混合氧化物作为阴极时，获得均匀组成的合金或金属间化合物。对于那些由于密度或蒸汽压的差异而目前难以制备的合金，这可能提供优于传统技术的优势。
Many reactive and refractory metals are currently produced industrially by reducing their compounds, including oxides, using a more reactive metal. In some cases, where there is substantial oxygen solubility in the metal, the oxygen is first removed by carbochlorination followed by reduction. Titanium and zirconium are made by reduction of the volatile tetrachlorides by magnesium. The processes consist essentially of two reduction steps: reducing magnesium chloride to magnesium metal and then reduction of the metal compound; this makes the overall reduction process relatively expensive. Electrodeoxidation is very simple in that the oxide to be reduced is rendered cathodic in molten alkaline earth chloride. By applying a voltage below the decomposition potential of the salt, it has been found that ionisation of oxygen is the dominant cathode reaction, rather than alkaline earth metal deposition. In the laboratory, this technique has been applied to reduce a large number of metal oxides to the metals, including titanium, zirconium, chromium, niobium, tantalum, uranium and nickel. Furthermore, when mixed oxides are used as the cathode, alloys or intermetallic compounds of uniform composition are obtained. This may offer advantages over conventional technology for those alloys that are difficult to prepare at present, owing to differences in either density or vapour pressure.