电脱氧法由Nb_2O_5直接制备金属铌  

Preparation of niobium by direct electrochemical reduction of solid Nb_2O_5

作　　者：邓丽琴[1] 许茜[1] 李兵[1] 翟玉春[1] 黄振奇[1] 

机构地区：[1]东北大学材料与冶金学院,沈阳110004

出　　处：《中国有色金属学报》2005年第4期541-545,共5页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(50374030)

摘　　要：采用熔盐电脱氧法,在800℃混合熔盐CaCl22NaCl中以烧结的Nb2O5为阴极,石墨坩锅为阳极制备了金属铌。研究了不同温度下烧结阴极形貌及其对电脱氧反应的影响,并考查了电解时间对阴极产物中氧含量的影响。结果表明:1200℃下烧结12h的阴极片具有良好的电化学反应性能;电脱氧过程中阴极片的脱氧速度不均匀;Nb2O5电极的还原由外向内,由高价向低价分步进行;阴极的孔隙大小和颗粒尺寸会影响电极反应的速度。The method of electro-deoxidation was used to reduce solid Nb_2O_5 to niobium in a CaCl_2-NaCl melt at 800℃. The sintered Nb_2O_5 pellets acted as the cathode, while graphite crucible as the anode. It was investigated that the sintering temperature of the oxide cathode and the duration of electrolysis affected the purity of the products. The results show that the electrochemical activation of the cathode can be enhanced after being sintered at (1200)℃ for 12h. The rate of electro-deoxidation for Nb_2O_5 is varied during electrolysis, and the rate at the beginning of electrolysis is much larger than that approaching the end. The electrochemical deoxidation of Nb_2O_5 in the molten salt is conducted step by step from outside of cathode pellets to inside. The speed of electrode reaction is affected by the sizes of hole and grain of cathode.

关 键 词：电脱氧 熔盐 五氧化二铌 铌 电化学 

分 类 号：TG146.4[一般工业技术—材料科学与工程] TF111.52[金属学及工艺—金属材料]