以三亚乙基四胺六乙酸为螯合剂络合返滴定钴的研究  

Study of Complexometric Back Titration of Cobalt with Triethylenetetraminehexaacetic Acid(TTHA)

作　　者：肖本毅[1] 刘锦昌[1] 

机构地区：[1]广州有色金属研究院分析室

出　　处：《分析试验室》1998年第2期33-35,共3页Chinese Journal of Analysis Laboratory

摘　　要：研究了以５－Ｂｒ－ＰＡＤＡＰ或３，５－Ｂｒ２－ＰＡＤＡＰ为指示剂，在ｐＨ６．０～６．５的六次甲基四胺介质中，用ＴＴＨＡ络合返滴定钴。实验表明，采用锌盐为返滴剂，在终点时有着非常敏锐、清晰的颜色变化，钴的检测范围为０．５～５０ｍｇ／５０ｍＬ。方法完全适用于钴合金、氧化钴、钴铁及钴电解液等中钴的测定，相对标准偏差＜１．５０％（ｎ＝５）。A new method of complexometric back titration of cobalt with TTHA using 5BrPADAP or 3,5Br2PADAP as the indicator at pH6.0～6.5 in hexamethylenetetramine medium has been studied.It is shown that the colour change is very sensitive and the analytical results are stable and accurate for cobalt in the range of 0.5～50mg/50mL.The interfering ions were separated using sodium nitritepotassium chloride mixed solution.The recovery of cobalt as potassium cobaltinitrite precipitate is above 99.5%.The method has been applied to determine cobalt in cobalt alloys,cobalt oxide,cobaltiron alloys and cobalt electrolyte.

关 键 词：TTHA 钴 亚硝酸钴钾 配合返滴定 

分 类 号：O614.812[理学—无机化学]