硫氰酸铵树脂相分光光度法测定微量钴（Ⅱ）

TEST OF TRACE Co￣(2+) WITH SULPHURIC-CYANATERESIN-PHASE SPECTROPHOTOMETRY

介绍了硫氰酸根和钴（Ⅱ）在有表面活性剂Ｔｗｅｅｎ—８０存在下生成络阴离子，与强碱性阴离子交换树脂进行交换，有色络合物富集显色于树脂相上，可进行树脂相分光光度测定．λｍａｘ为６３０ｎｍ，表观摩尔吸光系数ε为１．０３×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，钴（Ⅱ）在０～１．０ｍｇ·Ｌ－１范围内服从Ｂｅｅｒ定律．用此法测定ＶＢ１２针剂、无机盐试剂微量钴（Ⅱ），相对标准偏差分别为３．５５％和４．３８％，结果满意．

This paper introduces exchange of complex negative ion (Co(SCN)2-4 formedby sulphuric-cyanate with (Co2+)and strong base negative ion resin at surface activator,Tween-80,colored complex being riching in resin-phase in order to analyze trace Co2+ λmaxis 630 nm, the mola absorption coefficient e is 1.03 × 105L· mol-1·cm-1, Co2+ contentobeyS Beer’s law in scope of 0～1.0 mg. L-1. The relative criterion deviation of analysingtrace Cot2+ in VB12 and inorganic salts’ agent are 3.55% and 4.38%, respectively, using sul phuric-cyanate resin-phase spectrophotometry. So the results are satisfactory.