(上海大学 材料科学与工程学院，上海 200072)
摘 要: 采用固体透氧膜(SOM)法直接电解还原Nb2O5制备金属Nb。在CaCl2熔盐体系中，电解电压控制为3.2 V，以经过1 200 ℃预烧4 h成型的Nb2O5为阴极，氧化锆管内碳饱和的液态铜合金为阳极。研究电解时间分别为0.5、1、2和4 h以及不同温度下电解的特征规律和不同电解温度对阴极产物微结构的影响。结果表明：随着电解的进行，Nb2O5首先转变为Nb的一系列低价氧化物，进而才被还原成金属Nb；且随着实验温度的升高，电解速度相应加快，金属铌颗粒尺寸增大。与FFC法相比，SOM法具有更高的电解效率，1 150 ℃下的电解效率可达81.7%。
关键字: 固体透氧膜；Nb2O5；Nb；电化学；还原
（School of Materials Science and Engineering, Shanghai University, Shanghai 200072, China）
Abstract:Niobium was produced directly from Nb2O5 using solid oxygen-ion membrane (SOM). In molten flux CaCl2 system, electrolysis voltage is 3.2 V, Nb2O5 pellets preformed and sintered at 1 200 ℃ for 4 h and liquid metal saturated with carbon loaded in zirconia tube act as the cathode and anode, respectively. The electrochemical character of electrolytic process and the micro-structural features of the cathode pellets were studied at different temperatures for 0.5, 1, 2 and 4 h, respectively. The results show that Nb2O5 is transformed to a series of low value oxides firstly, and then proceed to the metal Nb with electrolysis. The electrode reaction rate and the grain of reduced metal increases with temperature increasing. SOM process has higher electrolysis efficiency comparing with FFC process. The electrolysis efficiency can be as high as 81.7%.
Key words: solid membrane; Nb2O5; Nb; electrochemistry; reduction
