碱消解-火焰原子吸收光谱法检测土壤中的六价铬方法改进

Determination of Cr(VI)in Soil by Alkali Digestion-modified Flame Atomic Absorption Spectrometry

针对国家环境保护标准《HJ 1082—2019》实验过程中出现的问题进行了分析和改进,研究了改进方法的线性关系、检出限、准确度和精密度等关键指标。结果表明改进方法在0.0~2.0 mg/L质量浓度范围内,六价铬的线性方程为y=0.0102x+0.00005,相关系数r=0.9999,线性良好,检出限为0.017 mg/L,在12.5~50μg添加范围内,平均加标回收率为88%~97%。检出限、准确度、精密度符合国标要求,且改进后的方法简单、易操作、易控,实现了样品的大批量检测,提高了检测人员的工作效率,为高效准确检测土壤和沉积物样品中的六价铬提供技术支撑。

In view of the problems in the experimental process of the national environmental protection standard"HJ 1082—2019",it analyzed and improved the key indicators such as linear relationship,detection limit,accuracy and precision of the improved method.The results show that the improved method is within the concentration range of 0.0 mg/L to 2.0 mg/L,the linear equation of hexavalent chromium is y=0.0102x+0.00005,the correlation coefficient r=0.9999,the linearity is good,and the detection limit is 0.3 mg/kg.In the range of 12.5~50μg,the average recovery rate of standard addition was 88%~97%.The detection limit,accuracy,and precision meet the requirements of the national standard,and the improved method is simple,easy to operate,and easy to control,which realizes the mass detection of samples,improves the production efficiency of the inspectors,and provides efficient and accurate detection of soil and sediment.The hexavalent chromium in the sample provides technical support.