高纯钴的制备

对目前高纯钴的制备方法进行了综述和评价。制备高纯钴的冶金工艺过程主要包括萃取法、膜分离法、离子交换法、电解法、区域熔炼法等，这些方法在除杂方面发挥着不同的作用。溶剂萃取法对大多数金属离子有很好的效果，但对Ni，Cu，Zn等金属离子的分离效果相对较差；膜分离法存在稳定性差、成本高的缺点；离子交换和萃取色层法对分离性质相近的元素有较好的效果，但存在容量低等问题；区域熔炼过程可以去除金属钴中的碱金属、碱土金属和气体杂质，并有利于生成纯度高、RRR值大的完整钴单晶。在总结上述各方法特点的基础上，提出了制备高纯钴的合理工艺。

Preparation of High Purity Cobalt

The various metallurgical processes of preparing high purity cobalt,including solvent extraction, ion-exchange, extraction chromatography, electrolysis refining and vacuum melting, play different roles in the removal of impurities: solvent extraction can remove most of the metallic impurities but with a poor effect for Ni, Cu, Zn; Liquid membrane has the disadvantages of instability and high costs; ion-exchange and extract chromatography are effective for separating the elements with similar properties, but with the disadvantage of low capability; zone refining can remove alkali metal, alkali earth metal and gas impurities easily and produce perfect cobalt crystal with higher RRR. The progresses in this filed was introduced in this paper. On the basis of aforementioned analysis, a practical process for manufacturing high purity cobalt was proposed.