四酸消解-电感耦合等离子体质谱法测定土壤中24种稀有元素的含量

Determination of 24 Rare Elements in Soil by Inductively Coupled Plasma Mass Spectrometry with Four Acid Digestion

建立了四酸消解-电感耦合等离子体质谱法测定土壤中铕(153Eu)等24种稀有元素含量的分析方法。讨论了酸消解体系和消解过程对测定稀有元素存在的干扰,通过选择合适的待测同位素以及编辑干扰元素校正方程校正质谱干扰,采用嵌片技术和碰撞模式去除物理干扰和基体干扰;建立"主要干扰权重"概念,对内标元素进行分析筛选,最终确定185 Re、193Ir作为内标元素。24种稀有元素标准曲线的线性相关系数均大于0.999,方法检出限为0.001~2.9mg·kg^-1。用3种土壤标准物质GSS-8、GSS-13、GSS-27进行精密度和准确度试验,相对标准偏差(n=6)为0.80%~19%,加标回收率为75.0%~128%,各元素的测定值均在认定值范围内。该方法适合在国家网土壤环境质量调查及其他相关工作和研究中推广和使用。

An analytical method for the determination of 24 rare elements such as europium(153Eu)in soil by inductively coupled plasma mass spectrometry with four acid digestion was established.The interference of acid digestion system and digestion process on the determination of rare elements was discussed.The mass spectrometry interference was corrected by selecting the appropriate isotope to be measured and the correction equation of the interfering element was edited.The physical interference and matrix interference were removed by using the inlay technique and collision mode.Establish the concept of"main interference weight",analyze and screen the internal standard elements,and finally determine 185Re and 193Ir as internal standard elements.The linear correlation coefficients of the standard curves of 24 rare elements were all greater than 0.999,and the detection limits of the method was 0.001-2.9 mg·kg^-1.The precision and accuracy tests were carried out with 3 kinds of soil reference materials GSS-8,GSS-13,GSS-27.Values of RSDs(n=6)in the range of 0.80%-19%,and the recovery in the range of 75.0%-124%.The measured value of each element was within the range of authorized values.This method is suitable for popularization and use in the national network soil environmental quality survey and other related work and research.