微波消解-MPT-AES法测定电池污染土壤中铅和汞

研究了用微波消解-MPT-AES法测定电池污染土壤中铅、汞含量的方法。考察了分析谱线、微波前向功率、载气流量、工作气流量和氧屏蔽气压力对铅、汞发射强度的影响,得出最佳实验条件。分析介质酸及共存离子对铅、汞测定的影响。实验结果表明,铅、汞的检出限分别为25.2,420.5 ng/mL,RSD(n=11)分别为1.8%和4.9%,并且测得它们的线性范围分别为0.1~100,5~100μg/mL。采用正交实验设计考察最佳土壤微波消解条件,采用工作曲线法测定其中铅、汞的含量,加标回收率分别为99.57%~100.03%和97.32%~98.24%。微波消解-MPT-AES法可成为测定电池污染土壤中铅、汞含量的行之有效的分析方法。

Determination of Pb and Hg in Cell Polluted Soil by Microwave Digestion- Microwave Plasma Torch- Atomic Emission Spectrometry

The determination of Pb and Hg in cell polluted soil by microwave digestion-microwave plasma torch atomic emission spectrometry(MPT-AES) was studied. The experimental conditions(analytical line,microwave forward power,flow rate of carrier gas,flow rate of support gas,and oxygen shielding pressure) were chosen and optimized.The effects of acid concentration and coexistent ions on determination of Pb and Hg were studied.The results show that the detection limits of Pb and Hg are 25.2 and 420.5 ng/mL,the relative standard deviations(n=11) are 1.8% and 4.9%,the linear ranges are 0.1～100 and 5～100μg/mL,respectively.The optimum experimental condition of soil microwave digestion was studied with orthogonal test.the contents of Pb and Hg were determined by the method of working curve,the rate of addition recovery are 99.57%～100.03% and 97.32%～98.24%.The combination of microwave digestion and MPT-AES is an effective method to determinate content of Pb and Hg in the cell polluted soil.