二溴对甲偶氮羧光度法测定Cu-Co合金中钴

来源期刊：冶金分析2011年第4期

论文作者：钟国秀 杨浩义 晏高华

文章页码：68 - 70

关键词：钴； 二溴对甲偶氮羧； Cu-Co合金； 分光光度法

Key words：cobalt； Dibromomethyl carboxyazo； copper-cobalt alloy； spectrophotometry

摘    要：研究了显色剂二溴对甲偶氮羧与钴的显色反应。pH 10.2的柠檬酸铵-氨水溶液中,钴与二溴对甲偶氮羧反应形成蓝色络合物,最大吸收波长为660 nm,表观摩尔吸光系数为1.77×10⁴ L·mol^-1·cm^-1,钴量在0~3.2 mg/L范围内符合比尔定律。方法用于Cu-Co合金中钴的测定,相对标准偏差小于2%,结果与亚硝基R盐光度法一致。

Abstract: The chromogenic reaction between the reagent Dibromomethyl carboxyazo and cobalt was studied.In ammonium citrate-ammonia solution at pH 10.2,cobalt reacted with Dibromomethyl carboxyazo,forming a blue complex which exhibited an absorption maximum at 660 nm with an apparent molar absorptivity of 1.77×10⁴ L·mol^-1·cm^-1.Beer′s law was obeyed in the range of 0-3.2 mg/L for cobalt.The proposed method has been applied to determine cobalt in copper-cobalt alloy with RSD(n=5) smaller than 2%.The results were consistent with those obtained by nitroso-R salt spectrophotometry.