流动注射在线吸附预富集-冷蒸气原子荧光法测定矿泉水中的痕量无机汞  

Determination of Trace Inorganic Mercury in Mineral Water by Flow Injection On-line Sorption Preconcentration-Cold Vapor Atomic Fluorescence Spectrometry

作　　者：訾洪静[1] 淦五二[1] 韩素平[1] 姜宪娟[1] 完玲中[1] 

机构地区：[1]中国科学技术大学化学系,合肥230026

出　　处：《分析化学》2009年第7期1029-1032,共4页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金(No.20675074)资助项目

摘　　要：研究了聚四氟乙烯管编结反应器(KR)在线吸附预富集技术与冷蒸气原子荧光联用测定矿泉水中痕量无机汞的方法。Hg2+与DDTC在线形成Hg2+-DDTC络合物并吸附在KR内壁上,采用电磁感应加热技术,用20%(V/V)HNO3在线加热洗脱并氧化预富集于KR内壁上的Hg2+-DDTC。洗脱液与KBH4溶液反应生成蒸气态汞,直接用冷蒸气原子荧光联用技术检测。20%(V/V)HNO3作为洗脱液的同时也为氢化发生提供了酸性介质。本方法未使用常用的有机洗脱液,具有操作简单和环保等优点。每小时可分析30个样品,最大吸附倍数为35倍,样品分析精密度RSD为2.2%(n=11),检出限(3σ)为2.0ng/L。Flow injection on-line sorption preconcentration and separation in a knotted reactor （KR） was coupled to cold vapor atomic fluorescence spectrometry for the determination of trace mercury in mineral water. Mercury was preconcentrated by on-line formation of mercury diethyldithiocarbamate complex （Hg-DDTC） and absorption of the resulting neutral complex on the inner walls of a knotted reactor. A 20% （V/V） HNOz solution heated by electromagnetic induction heating technique was used as eluent to remove the absorbed Hg-DDTC from the KR, and then the vapor mercury generated by mixing the resulting solution and KBH4 was determined on-line by cold vapor atomic fluorescence spectrometry. The 20% HNO3 was employed as both the efficient eluent and the required acidic medium for subsequent mercury vapor generation in our work. Using 20% HNO3 instead of conventional organic solvent as eluent, the proposed method is simple, easy operational and environmentally friendly. Under the optimal experimental conditions, the sample throughput was approximatively 30/h with an enhancement factor of 35. The detection limit of mercury was 2. 0 ng/L. The precision（RSD, n = 11 ） was 2. 2% at the 0. 1μg/L Hg^2＋ level.

关 键 词：编结反应器 电磁感应加热 冷蒸气原子荧光光谱 无机汞 矿泉水 

分 类 号：TS275[轻工技术与工程—农产品加工及贮藏工程]