全自动石墨消解-原子荧光法测定土壤总汞

Determination of the Total Mercury in Soil by Atomic Fluorescence Spectrometry Coupled with Fully-Automatic Graphite Digestion

采用全自动石墨消解-原子荧光光度法对土壤总汞进行测定,确定最佳消解时间为1 h,消解液最佳用量为8.0 mL。方法在总汞质量浓度为0.2～2.0μg/L范围内具有良好的线性,相关系数为0.999 9,当取样量为0.500 0 g时,检出限为0.002 mg/kg;测定不同标准土壤样品总汞的结果均在保证值范围内,精密度为4.0%～7.0%,加标回收率为95.0%～108.5%;对甘肃省实际土壤及沉积物样品测定进一步验证了方法的适用性。该法适合大批量样品分析,对于提高工作效率有重要意义。

Fully-automatic graphite digestion method was developed and used in the determination of total mercury in soil by atomic fluorescence spectrometry （AFS）. The optimum digestion time was 1 h using 8.0 mL digestion solution. Good linear relationship with coefficient value of 0. 999 9 was obtained when the total mercury concentration was in the range of 0.2 - 2.0 μg/L. The detection limit was 0. 002 mg/kg when the sampling amount was 0. 500 0 g. For different standard soil samples,the results of total mercury were all within the guaranteed range. The precision was in the range of 4.0% -7.0% , and the recoveries were from 95.0% to 108.5% using the standard addition method. This method was further tested on the soil and sediment samples from Gansu Province. It is particularly suitable for rapid determination of large amount of soil samples to ensure high precision and high accuracy measurement.