一种高选择性固相萃取剂的合成及对汞(Ⅱ)的分离富集特性

Preparation of a Selective Solid Phase Extractor and Its Application to Separation and Preconcentration of Trace Heavy Metal

制备了二甲酚橙键合硅胶(SGMXO)固相萃取剂,研究了它对常见重金属离子的分离富集行为,发现对水中痕量Hg2+有较好的选择性分离富集效果。系统考察了溶液的pH、过柱流速、洗脱液浓度及流速、柱始漏量及不同金属离子对Hg2+的定量回收的影响。在pH=1.0条件下,可在Cd2+、Pb2+、Cu2+、Mn2+等多种性质相近的金属离子存在时,对Hg2+进行选择性分离富集。所合成的固相萃取剂在使用50次后仍能重复出实验现象。该法用于对实际样品中Hg2+的分离富集,回收率在99%以上。

A novel method was established for the preparation of solid phase extractor by modified xylenol orange onto silica gel. Analytical characteristics of the xylenol orange modified silica gel have been investigated. It was found that this stationary phase has quite good application to selective separation of trace amount of Hg^2＋ from Cd^2＋ , Co^2＋ , Ni^2＋ , Mn^2＋ , Fe^3＋ , Pb^2＋. The influences of analytical parameters including pH of the aqueous solution, flow rates of sample and eluent solutions, sample volume, break through volume etc. on the quantitative recoveries of Hg^2＋ were investigated. The solid phase extractor can be reused at least 50 times. The presented preconcentration procedure was applied to the determination of Hg^2＋ in environmental samples, high recoveries were obtained.