共振光猝灭法测定环境水样中痕量硒  

Determination of Trace Selenium in Environmental Water Samples by Using Resonance Light Quenching Method

作　　者：李人宇[1,2] 李咏梅[2,3] 吴俊杰[1] 王显金[1] 熊情[1] 

机构地区：[1]连云港师范高等专科学校,江苏连云港222006 [2]淮海工学院江苏省海洋资源开发研究院,江苏连云港222005 [3]淮海工学院化学工程学院,江苏连云港222005

出　　处：《岩矿测试》2011年第3期328-332,共5页Rock and Mineral Analysis

基　　金：连云港市科技项目资助(SH0816);江苏省海洋资源开发研究院科技开放基金项目资助(JSIMR09C08);2010年江苏省高等学校大学生实践创新训练计划立项项目资助(680);淮海工学院自然科学基金项目资助(Z2008019)

摘　　要：在阿拉伯树胶（AG）存在下,0.14 mol/L硫酸介质中,硒（Ⅳ）与过量的I-反应生成I3-,加入乙酸钠后I3-与亚甲基蓝反应成离子缔合物,在波长288 nm处共振光猝灭,建立了共振光散射法测定痕量硒的方法。确定了碘化钾、亚甲基蓝、乙酸钠和增溶剂阿拉伯树胶溶液的浓度,在室温（20-30℃）下反应15 min,提高了体系的灵敏度和稳定性。共振光散射猝灭值与硒（Ⅳ）浓度在0-0.24μg/mL范围内线性关系良好,方法检出限为1.01μg/L。Fe^3＋、Pb^2＋、Cu^2＋和Zn^2＋的干扰用EDTA消除。方法用于测定环境水样中痕量硒,相对标准偏差（RSD）为1.3%-3.6%（n=5）,回收率为97.4%-100.8%。A new resonance light quenching method for the quantification of trace selenium has been developed.The method is based on the reaction of Se（Ⅳ） with excess I-in 0.14 mol/L H2SO4 solution to produce I-3 with arabic gum（AG）.After adding NaAc,I-3 reacts with methylene blue（MB） to form an ion-association complex,resulting in resonance light quenching at a wavelength of 288 nm.The optimum concentrations of KI,MB,NaAc and solubilizer AG were decided.In addition,reaction for 15 min at room temperature（20-30℃） was found out.As a result,the sensitivity and stability of the system was improved.Good linear relationship between resonance light quenching intensity and Se（Ⅳ） concentration occurs in the content range of 0-0.24 μg/mL.The detection limit is 1.01 μg/L.The interferences of Fe^3＋,Pb^2＋,Cu^2＋ and Zn^2＋ are eliminated by EDTA.This method was applied to the quantification of trace selenium in environmental water samples with RSD of 1.3%-3.6%（n=5） and recoveries from 97.4% to 100.8%.

关 键 词：硒 环境水样 共振光猝灭法 碘离子 亚甲基蓝 阿拉伯树胶 

分 类 号：O613.52[理学—无机化学]