电感耦合等离子体质谱法测定环境评价性土壤中铬铜镉铅

Determination of Cr,Cu,Cd and Pb in environmental evaluation soils by inductively coupled plasma-mass spectrometry

针对环境评价性土壤,采用HNO_3-HClO_4-HF消解样品、HNO_3提取技术,以52Cr、65Cu、114Cd、208Pb作为测定同位素,采用间接经验公式校正质谱干扰,最终实现了电感耦合等离子体质谱法(ICP-MS)同时对Cr、Cu、Cd、Pb等4种重金属的测定。详细对比分析了HCl-HNO_3-HClO_4-HF、HCl-HNO_3-H_2SO_4-HF、HNO_3-HClO_4-HF消解法等3种试样处理方法对土壤成分分析标准物质的分析数据,结果表明:HNO_3-HClO_4-HF消解法测定值与认定值相符。Cr、Cu、Cd、Pb的校准曲线相关系数均达0.9999以上,方法测定限(μg·L^(-1))分别为:Cr1.54,Cu 0.83,Cd 0.024,Pb 0.29。将方法应用于土壤4种重金属元素的测定,结果与认定值基本一致,相对标准偏差(RSD,n=12)均小于8%,加标回收率在96.7%~102.3%。方法应用于实际环境评价性土壤样品分析,结果与X射线荧光光谱法(XRF)相吻合。

The environmental evaluation soils were decomposed by mixed acid of HN03-HF-HC104 and extracted by HN03. 52Cr,65 Cu,114Cd and 208Pb were chosen as determining isotopes and the mass spectral interference were calibrated by the indirect experi-ence formula. Four trace elements of Cr,Cu,Cd and Pb were successfully determined by inductively coupled plasma-mass spectrom- etry（ ICP-MS）. The experimental data were contrasted in details with the other three digestion methods such as HC1-HN03-HC104- HF,HC1-HN03-H2S04-HF and HN03-HC104-HF. The results show that the correlation coefficients of calibration curves were both up to 0. 999 9. The detection limits（ 10SD, （μg· L^-1 ） arel. 54 for Cr,0. 83 for Cu,0. 024 for Cd and 0. 29 for Pb. The measured val-ues with the proposed method were in consistent with the certified values, the relative standard deviations（ RSD,n= 12） were less than 8%,and the recoveries were between 96. 7% ？102. 3%. In the analysis of the actual environmental evaluation soil s a m p l e s, the results were consistent with those obtained by XRF.