电感耦合等离子体质谱法测定钢铁中15种痕量元素

来源期刊：冶金分析2011年第5期

论文作者：成勇 黄木辉

文章页码：31 - 35

关键词：电感耦合等离子体质谱法； 钢铁； 痕量元素； 内标校正

Key words：inductively coupled plasma mass spectrometry； steel； trace element； internal standard correction

摘    要：以HNO₃消解样品后,采用电感耦合等离子体质谱法(ICP-MS)测定钢铁中As,Pb,Sn,Sb,Zr,Bi,Zn,Cu,Co,Ni,Cr,Mo,V,Ti,Als共15种痕量元素。考察了待测元素的质谱干扰情况,通过优选高丰度并且受到干扰影响程度较小的分析同位素,克服了基体铁的同量异位素及其与ICP中Ar、O、H等结合所产生的多原子离子的质谱干扰。方法以Rh作为内标元素进行内标校正,明显改善长时间连续测定钢铁样品的稳定性,提高测定结果的精密度,有效消除铁基体等产生的基体效应和对接口锥变化的影响。各元素的检出限在0.03～1.95μg/L范围。方法用于测定钢铁中上述痕量元素的相对标准偏差(RSD),除Zr外,其他元素在2.1%～5.2%(长时测定),对有证参考物质分析,分析值与认定值一致。

Abstract: The sample was digested in HNO₃.Then,fifteen trace elements in steel including As,Pb,Sn,Sb,Zr,Bi,Zn,Cu,Co,Ni,Cr,Mo,V,Ti and Al were determined by inductively coupled plasma mass spectrometry(ICP-MS).The mass spectral interference of testing elements was investigated.By optimizing the isotopes with high abundance and low interference,the mass spectral interference of isobaric elements of matrix iron and their polyatomic ions formed with Ar,O and H in ICP were eliminated.In this method,the Rh was used as internal standard element for correction.It significantly improved the long-term continuous determination stability of steel samples,enhanced the precision of determination results,and effectively eliminated the matrix effect of iron and the influence of interference change.The detection limit of established method was 0.03-1.95 μg/L.The proposed method was applied to the determination of trace elements above(except Zr) in steel,and the relative standard deviation(RSD) for long-term determination was in the range of 2.1%-5.2%.The analytical results were consistent with the certified valules.