铜-铜试剂分离富集-电感耦合等离子体发射光谱法测定地下水中痕量汞

Determination of Trace Hg in Underground Water by Inductively Coupled Plasma-Atomic Emission Spectrometry with Cu-DDTC Separation and Enrichment

利用铜(Ⅱ)与铜试剂反应生成鳌合物沉淀的同时,能将痕量汞(Ⅱ)共同沉淀出来的特性,将汞(Ⅱ)分离富集,电感耦合等离子体发射光谱法测定地下水中汞的含量。在汞标准溶液中,加入不同量的铜和铜试剂测定汞的真实含量,最终确定铜和铜试剂最佳加入量。通过优选分析线、背景恰当扣除处理,水溶液体积由200 mL浓缩至5 mL,富集40倍后汞的检出限可达0.1μg/L。方法用于测定国家标准物质GBW(E)080006和实际样品,测定值与标准值、国家标准方法测定值一致,均在允许误差范围内。方法精密度(RSD,n=12)小于10%,可满足地下水中痕量汞的测定要求。

A method for the determination of Hg in underground water by inductively coupled plasma-optical emission spectrometry（ICP-AES） has been developed.Hg（Ⅱ） was separated and enriched according to the coprecipitation of Hg（Ⅱ） by Cu（Ⅱ） and DDTC chelate compound in water.In order to detect the accurate value of Hg,different amount of Cu and DDTC was loaded into Hg standard solution to optimize the added amounts of Cu and DDTC.The lowest detecting concentration of Hg was 0.1 μg/L after selecting optimal analyzing line,correcting background reasonably,and condensing the volume of water from 200 mL to 5 mL with enrichment factor of 40.Certified Reference Materials and practical samples were analyzed and the results were in good agreement with the certified values obtained following national standard methods.The relative standard deviation（RSD,n=12） is less than 10%.Therefore,the proposed method meets the requirements for determination of trace Hg in underground water.