全自动石墨消解-ICP-MS法测定土壤中16种金属元素

Determination of 16 metal elements in soil by automated graphite digestion-ICP-MS

建立全自动石墨消解-电感耦合等离子体质谱(ICP-MS)法同时测定土壤中16种金属元素(Li、Be、V、Cr、Mn、Co、Ni、Cu、Zn、Mo、Cd、Ba、Tl、Pb、Th、U)含量的方法。采用HCl-HNO3-HF-HCl O4消解液对土壤样品进行全自动消解,通过优化ICP-MS仪器参数,选择Rh和Re作为内标元素及碰撞池模式消除干扰,测定土壤中16种金属元素。结果表明,16种金属元素均呈现良好的线性关系,相关系数均大于0.999,检出限在0.002~7.18mg·kg^(-1)之间;使用HCl-HNO3-HF-HCl O4的全自动石墨消解方法,样品消解效果良好,对有证土壤成分分析标准物质GBW 07404(GSS4)和GBW 07405(GSS5)的测定值与标准值相符,相对标准偏差为0.72%~5.20%,相对误差为0.27%~8.33%;按所建立的实验方法对实际样品测定并进行加标回收实验,加标回收率在94.7%~101.2%之间。该方法精密度与准确度高,测试结果稳定,自动化程度高,满足对土壤中金属元素的分析测定要求。

A method for simultaneous determination of 16 metal elements(Li,Be,V,Cr,Mn,Co,Ni,Cu,Zn,Mo,Cd,Ba,Tl,Pb,Th,U)in soil by automatic graphite digestion-inductively coupled plasma mass spectrometry(ICP-MS)was established.The soil samples were digested by hydrochloric acid-nitric acid-hydrofluoric acid-perchloric acid digestion solution.By optimizing the ICP-MS instrument parameters,Rh and Re were selected as internal standard elements and collision cell mode to eliminate interference,and 16 metal elements in soil were determined.The results showed that the 16 metal elements showed a good linear relationship,the correlation coefficients were greater than 0.999,and the detection limits were 0.002~7.18mg·kg^(-1).The sample digestion effect was good.using the automatic graphite digestion method of hydrochloric acid-nitric acid-hydrofluoric acid-perchloric acid.The measured values of certified soil component analysis reference materials GBW07404(GSS4)and GBW07405(GSS5)were consistent with the standard values.The relative standard deviation was 0.72%~5.20%,and the relative error was 0.27%~8.33%.The actual samples were determined according to the established experimental method and the spiked recovery experiment was carried out.The spiked recovery rate was in the range of 94.7%~101.2%.The method has high precision and accuracy,stable test results and high degree of automation,which meets the requirements for the analysis and determination of metal elements in soil.