离子色谱-柱后衍生-紫外可见检测法测定地下水中痕量六价铬

摘要

The method was proved to be effective in Cr(Ⅵ)determination,and the analysis was ac-complished in 8 minutes with a favorable peak profile. The correlation coefficient was >0.9999 for Cr(Ⅵ) in the range of 0.05-5 μg/L,and the detection limit was as low as 0.008 μg/L. The high accuracy and precision were proved by the satisfactory recovery rates (94%-106%)and RSDs (0.6%-4.0%)for 3 different kinds of actual groundwater samples. The high concentration of sulfate had no influence in Cr (Ⅵ)detection while the high concentration of chloride could compromise the chromatography.This meth-od can be used for Cr(Ⅵ)determination in groundwater.%建立了离子色谱-柱后衍生-紫外可见检测法直接测定地下水中痕量六价铬的方法,确定了方法的性能指标,开展了干扰实验的研究。研究发现,本方法可在8分钟内完成分析,六价铬峰型尖锐,方法标准曲线线性范围0.05~5.00μg/L,相关系数≥0.9999。方法检出限较低(0.008μg/L),精密度和准确度较高,3种地下水实际样品的加标回收率为94%~106%,RSD 为0.6%~4.0%(n=8)。高浓度 SO42-(500~3000 mg/L)对六价铬测定无干扰,而 Cl-(>500 mg/L)可在一定程度上干扰六价铬峰形。本方法耗时短、选择性强、灵敏度高、前处理简单、干扰较少,相对常规方法能够更好地满足地下水中六价铬测定的实际需要。