Preconcentration and Determination of Palladium(II) by An Organic Solvent-Soluble Membrane Filtration-Graphite Furnace Atomic Absorption Spectrometry

He Runjuan, Qian Chunyan, Zhu Ruohua^*, Gu Xuexin
(Department of Chemistry, Capital Normal University, Beijing 100037)

Abstract A method for the preconcentration and determination of trace Pd(II) by graphite furnace atomic absorption spectrometry (GFAAS) was described. It was based on the formation of Pd(II)-2-(5-chloro-2-pyridylazo)-5-dimethylaminoaniline (5-Cl-PADAM)-exadecyltrimethylammonium bromide (CTMAB) complex in heavy acid medium. The complex was collected on a soluble membrane filter and the detection of the solution obtained after dissolving and analyzing the membrane in a proper solvent. The conditions for the formation and collection of the complex including pH, effect of surfactants, aperture of the membrane filter, effect of matrix modifiers etc. were optimized. Under the optimized conditions, the linear range was found in the range of 0.2～2.3ng× mL^-1 and 2.3～7ng× mL^-1 with the R=99.95% and R=99.98% respectively. The limit of detection achieved was 0.03ng× mL^-1 after separation. The method was used for the determination of the soil and ore samples with satisfaction.
Key words Palladium, 2-(5-Chloro-2-pyridylazo)-5-dimethylaminoaniline(5-Cl-PADMA), Separation, Graphite furnace atomic absorption spectrometry (GFAAS)

有机溶剂可溶性滤膜预富集-石墨炉原子吸收法测定痕量钯

摘要 强酸性条件下，钯(Ⅱ)与2-[(5-氯-2-吡啶)偶氮]-5-二甲氨基苯胺(5-Cl-PADMA)及溴化十六烷基三甲铵(CTMAB)可生成络合物，络合物经0.22m m孔径的混合纤维素膜富集后，用小体积的混合有机溶剂(乙二醇单甲醚和N,N-二甲基甲酰胺)溶解，加入一定量的混合基体改进剂 (抗坏血酸和氯化铵)后，用石墨炉原子吸收法(GFAAS)测定其中的钯含量。实验结果表明，钯含量在0.2～2.3ng/mL和2.3～7ng/mL范围内线性关系良好，检出限为0.03ng/mL，用于矿石、土壤样品中痕量钯的测定，结果令人满意。
关键词 钯 2-[(5-氯-2-吡啶)偶氮]-5-二甲氨基苯胺(5-Cl-PADMA) 富集 石墨炉原子吸收法(GFAAS)

贺闰娟 女，25岁，硕士生，现从事痕量贵金属元素测定的研究。 ^*联系人，E-mail:zhurh@mail.cnu.edu.cn
2003-12-04收稿，2004-05-28接受

(PDF全文下载c04111)