离线预富集电感耦合等离子体质谱法测定天然水体中溶解态硅  

Determination of Dissolved Silicon in Natural Water by Inductively Coulpled Plasma-Mass Spectrometry after Off-line Preconcentration

作　　者：徐毅[1] 瞿建国[1] 张经[1] 

机构地区：[1]华东师范大学河口海岸科学研究院,上海200062

出　　处：《分析化学》2007年第6期877-879,共3页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金(No.40476036)资助项目

摘　　要：以Mg（OH）2共沉淀和阳离子交换树脂作为离线预富集方法,建立了天然水体中溶解态硅电感耦合等离子体质谱（ICP-MS）测定方法.实验采用NaOH作为Mg（OH）2沉淀引发剂,以共沉淀方式将溶解态硅元素从天然水体中分离富集,再利用阳离子交换树脂将基体Mg^2＋清除,并对洗脱液流速、共沉淀碱度等条件进行优化选择.结果显示：Mg（OH）2共沉淀步骤可定量回收溶解态硅,控制溶液通过阳离子交换树脂的速率可将硅元素与基体Mg^2＋完全分离而不会造成损失.不同基体的水样的加标回收率为99%～105%,方法检出限为4.5 μg/L（3S, n=8）,方法精密度RSD小于3%.A method based on Mg（OH） 2 coprecipitation followed by cation-exchange separation for the determination of dissolved silicon in natural waters by ICP-MS was developed. Studies on the parameters of coprecipitation indicate that dissolved Si could be quantitatively removed from solution by the formation of brucite Mg（ OH）2, initiated by the addition of NaOH. Separation of Si from Mg^2＋ was achieved using cation-exchange resin with 98% yields. The optimized procedure provides Si recoveries of various natural water samples are 99% - 105%. The detection limit（3 s, n = 8 ） of dissolved Si is 4.5 μg/L. The reproducibility （n = 8） of the present study is less than 3%.

关 键 词：电感耦合等离子体质谱法 溶解态硅 共沉淀 阳离子交换 

分 类 号：O657.63[理学—分析化学]