电感耦合等离子体质谱法测定大气颗粒物中微量元素及铂族元素

大气颗粒物样品采集量较少,一般只有5~10mg左右,其中铂族元素含量很低并且受到Cu、Ni、Cd、Zr、Hf等元素的严重干扰,直接测定误差很大,必须要进行分离富集。因此,同时测定其中的微量元素及铂族元素非常困难。本文利用HF和HNO3在封闭溶样装置中对大气颗粒物样品进行消解,样品完全消解后,分取约1/4的样品溶液,以Ir作为内标元素等离子体质谱法测定微量元素,然后将剩余样品通过Dowex,50W X8阳离子树脂和P507萃淋树脂混合交换柱,分离基体元素及干扰元素,以Ir为内标等离子体质谱法测定Pt、Pd、Rh三个铂族元素以及Re和Au。实现了一次溶样同时测定大气颗粒物中的微量元素、稀有分散元素及铂族元素。国际标样结果稳定可靠。

Determination of Trace Elements and Platinum Group Elements in Airborne Particulate Matter by Using Inductively Coupled Plasma-mass Spectrometry

Determination of trace elements and platinum group elements(PGE)in atmospheric particle is very difficult, because of low sample mass(5~10 milligram)and interference of Cu, Ni, Cd, Zr and Hf to PGE. In this study, HF and HNO₃ were used to digest samples with Teflon-stainless steel pressure bombs. About 1/4 of the digested solution was used for determination of trace elements by ICP-MS using Ir as an internal standard. The remaining solution was passed through an ion exchange column containing 50W-X8 cation exchange resin and P507 extraction chromatograph resin to remove interference elements. The passed solution was used for determination of Pt, Pd, Rh, Re and Au by ICP-MS using Ir as internal standard. The proposed method can be used for measuring trace elements and PGE in a single sample preparation. Results of international certified reference material agree well with the certified(or reported)values.