便携式X射线荧光光谱法在土壤重金属快速检测中的应用

摘要

考察了仪器检测时间、土壤粒径、紧实度和含水量对 Olympus Delta Professional 型便携式 X 射线荧光光谱仪（PXRF）检测土壤中常见重金属元素（Cr、Ni、Cu、Zn、As 和 Pb）的影响。结果显示，仪器检测时间和土壤含水量是影响检测结果的两个主要因素，土壤粒径和紧实度对结果的影响并不明显。对标准土壤 GSS-4、GSS-5和 GSS-27进行5次重复测定的准确度为79％～105％，精密度为0．45％～11．75％，表明该仪器对土壤中重金属检测的准确度和精密度良好。实验室条件下检测结果与 ICP-OES 检测结果的相关性较好，除了 Cr 和 As 元素的决定系数 R2在0．7～0．8外，其他元素的 R2均＞0．9，表明对样品进行简单的前处理后，该仪器可用于土壤中重金属元素的快速测定。%The effects of measurement time,soil partial size,compaction and moisture content on determi-nation of heavy metals (Cr,Ni,Cu,Zn,As and Pb)in soil by Olympus Delta Professional portable X-ray fluorescence spectrometry were studied.The results showed that measurement time and soil moisture con-tent were two main factors affecting the measurements,whereas soil partial size and compaction had no ob-vious effect on the measurements.The accuracy range of 5 replicate determinations of soil reference mate-rials GSS-4,GSS-5 and GSS-27 was 79% ~105%,and the relative standard deviations (RSD)range was 0.45% ~11.75%,which showed that PXRF can be used for the detection of heavy metals in soil.The re-sult showed that the data measured in the laboratory had better relationship with data measured by ICP-OES.The correlation coefficients of all elements were above 0.9,except Cr and As,whose R2 were be-tween 0.7 and 0.8,which showed that PXRF can be used for rapid determination of heavy metals in soil, if the sample was pre-treated.