铜试剂显色树脂相分光光度法测定水中痕量Cu(Ⅱ)

Determination of Trace Cu(Ⅱ) in Water Samples with DDTC Resin-phase Spectrophotometry

提出了在ｐＨ８５０条件下，Ｃｕ（Ⅱ）与铜试剂（ＤＤＴＣ）生成有色配合物，与强碱性阴离子树脂交换吸附，树脂相光度法测定痕量Ｃｕ（Ⅱ）的新方法。结果表明，有色配合物树脂相的最大吸收波长为４２０ｎｍ，Ｃｕ（Ⅱ）含量在０～２０ｍｇ·Ｌ－１范围内符合Ｂｅｅｒ定律，表观摩尔吸光系数为５１×１０４Ｌ·ｍｏｌ－１·ｃｍ１。用于水样中痕量Ｃｕ（Ⅱ）的测定，相对标准偏差小于２３％，加标回收率９７％～１０２％。

A resin-phase spectrophotometric method for the determination of trace Cu(Ⅱ) based on formation of the colored complex with DDTC under the condition of pH 8 50 is described.The maximum absorption wavelength is at 420 nm and the apparent molar absorption coefficient is 5 1×10 4 L·mol 1 ·cm 1 .The Beer's law is obeyed for the concentration of Cu(Ⅱ) within the range 0～2 0 mg·L 1 .The proposed method has been applied to the determination of trace Cu(Ⅱ) in water samples.The recoveries are from 97% to 102% and the relatives standard deviation is less than 2 3%.