巯基葡聚糖凝胶分离富集对硝基苯基重氮氨基偶氮苯分光光度法测定微量汞(Ⅱ)  

Spectrophotometric determination of trace mercury(Ⅱ) with p-nitrophenyldiazoaminoazobenzene after separation and enrichment by mercapto-dextran gel

作　　者：陈文宾[1] 陈璧珠 林艳[1] 许兴友[1] 马卫兴[1] 

机构地区：[1]淮海工学院化学工程系,江苏连云港222005

出　　处：《冶金分析》2009年第12期61-65,共5页Metallurgical Analysis

基　　金：淮海工学院海洋生物技术重点建设实验室基金项目(2005HS010;2005HS001);江苏省科技厅自然科学基金(BK2005045);淮海工学院自然科学基金(Z2006)

摘　　要：研究了在吐温-80溶液存在下，对硝基苯基重氮氨基偶氮苯与汞（Ⅱ）发生显色反应的条件，建立了新的测定微量汞（Ⅱ）的高灵敏度分光光度法。实验结果表明，在硼砂-氢氧化钠介质中，对硝基苯基重氮氨基偶氮苯与汞（Ⅱ）发生灵敏的显色反应，生成络合比为4：1的橙红色络合物；络合物的最大吸收峰位于484nm，表观摩尔吸光系数为1．4×10^7L·mol^-1·cm^-1；在10mL溶液中，汞（Ⅱ）量在0．08～0．25μg之间符合比尔定律，检出限为0．002mg／L；巯基葡聚糖凝胶分离富集后显色反应具有较强的抗干扰能力，可用于水、铅锌矿样品中微量汞㈣的测定，结果与原子吸收光谱法相一致，方法的回收率在97．29／6～104．7％之间，测得其相对标准偏差（n=6）≤3．2%。The color reaction of chromogenic agent p-nitrophenyldiazoaminoazobenzene with Hg（Ⅱ） was studied in the presence of Tween-80. A novel spectrophotometric determination of trace Hg（Ⅱ） with high sensitivity was established. The results showed that, in Na2B4O2-NaOH medium, Cadion A reacted with Pig（Ⅱ） to form a orange red stable complex with the molar ratio of reagent ： metal of 4 ： 1. The maximum absorption peak of the complex was located at 484 nm with the apparent molar ab- sorptivity of 1.4 ×10^7 L·mol^-1· cm^-1. In 10 mL of solution , Beer＇s law was obeyed for 0.08- 0. 25 μg of Hg（Ⅱ）, and the detection limit is 0. 002 mg/L. Interference from existence ions could be avaided by separation with mercapto-dextran gel. This method was applied to the determination of Hg （Ⅱ） in water and lead-zinc ore samples. The results was consistent with those obtained by AAS method. Recovery was in the range of 97.2%-104.7%, and the RSD（n=6） was lower than 3.2%.

关 键 词：对硝基苯基重氮氨基偶氮苯 分光光度法 汞(Ⅱ) 巯基葡聚糖凝胶 分离富集 

分 类 号：O657.32[理学—分析化学]