电感耦合等离子体质谱法测定灌溉水中7种重金属及其定性分析

实验用ICP—MS同时测定农田灌溉水中铬、镍、铜、锌、砷、镉、铅等7种重金属元素,在优化的仪器条件下,各元素的标准曲线相关系数全部达到0.9999以上;样品测定精密度为1.52%～4.10%;各元素检出限在0.000246μg.L-1～0.260μg.L-1之间;样品加标回收率在91.6%～112.5%之间。测定国家标准物质铜铅锌镉镍铬和砷环境标准样品,各元素的准确度达到97.1%～106.4%,结果令人满意。实验证明采用该方法对灌溉水中多元素同时进行测定,具有线性范围宽、精密度高、灵敏度高、准确性好、简单快速的优点。同时采用半定量分析方法对灌溉水进行定性分析,对于含量在0.1mg.L-1数量级以上的元素其半定量结果准确度较高;若元素含量在0.01mg.L-1数量级以下,则半定量结果准确度较差。

The Determination and Qualitative Analysis of Heavy Metals in Irrigation Water by ICP-MS

ICP-MS was used to determinate chromium,nickel,copper,zinc,arsenic,cadmium and lead in irrigation water.In the optimized instrument conditions,the correlation coefficient of calibration curves was as high as 0.9999,the precision of determination were 1.52%～4.10%,the detection limit of each element was between 0.000246μg·L-1 and 0.260μg·L-1 and the recovery rates were 91.6%～112.5%.Determinating national standard substances,the accuracy of the elements reached 97.1%～106.4%.The results are satisfactory.Experiments proved that the method of determination irrigation water is simple,sensitive,accurate,rapid and wide linear range.At the same time,semi-quantitative analysis method for qualitative analysis of irrigation water has better accuracy if the element content is greater than 0.1mg·L-1.If the element content is lower than 0.01mg·L-1,semi-quantitative analysis method has baddish accuracy.