痕量锌的在线流动注射阴离子交换富集分离法

The Determination of Zinc in Hair by a Flow-injection System with On-line Anion-exchange Preconcentration Separation and Atomic Absorption Spectrometry

提出以氯离子与金属离子形成络阴离子，然后用强碱性阴离子交换树脂进行流动注射在线富集和分离的方法。实验表明，本法对锌离子有很高的选择性和富集效率，不仅可分离常见干扰离子，而且使火焰原子吸收法测锌的检测限提高到０．１μｇ／Ｌ，已用于头发样品中痕量锌的在线富集、分离和原子吸收法测定。

A flow-injection system with on-line anion-exchange preconcentration and sep-aration on anion-exchange resins was described for the determination of zinc in hair at μg/Llever using flame atomic absorption spectrometry.For preconcentration and separation achloride(chlorhydric acid) was used as complexing agent or eluant. The zinc ions will be ex-changed and preconcentrated with forms of zinc-chloride complexation when the concentra-tion chlorhydric acid is higher than 1.0mol/Land will be eluted and separated with forms ofzinc cation when the concentration chlorhydric acid is lower than0.005 mol/L.The selectivi-ty of this system depends on the concentrat on of chlorhydric acid. When the concentration ofchlorhydric acid used as complexing agent and eluant are1.0 mol/L and 0.005 mol/L,re-spectively,zine can be separated completely from other interferences.The detection limit forzine is 0.1μg/L.