原子吸收法测定羰基铁中的铅和汞

Determination of the amount of lead and mercury in carbonyl iron with atomic absorbance spectrometry

目的：建立羰基铁中铅和汞的含量测定方法。方法：羰基铁经硝酸消解后，以硝酸镍为基体改进剂，在283．3nm波长处用石墨炉原子吸收法洲定铅含量。羰基铁经硝酸-硫酸消解后，以酸性氯化亚锡为还原剂，在253．7mn波长处用冷原子吸收法测定汞含量。结果：铅在0～80ng/mL的范围内线性良好，r=0．9992（n=6），平均回收率89．9％；汞在0～20ng／mL的范围内线性良好．r=0．9993（n=6）。平均回收率90．2％；同时测定的杨树叶标准物质中铅和汞的含量在标准参考值范围内。结论：该方法线性理想，回收率良好。适用于羰基铁中铅和汞含量的测定。

Objective：To develop a method for determination of lead and mercury in carbonyl iron. Methods： The sample being digested with HNO3, with nickel nitrate as interference suppressing agent, under 283.3 nm, the lead was determined with Graphite Furnace Atomic Absorbance Spectrometry. The sample being digested with HNO3-H2SO4, with Tin （Ⅱ） Chloride Dihydrate as reducing agent, under 253.7 nm, mercury was determined by cold vapor absorption. Results： Lead is linear in the range of 0～80 ng/mL, r = 0.9992 （n= 6）, average recovery is 89.9% ; mercury is linear in the range of 0 ～ 20 ng/mL, r = 0.9993 （n = 6 ）, average recovery is 90.2 % ; and the result of standard substance （poplar leaves ） is within the limits of reference. Conclusions： This method has a good linearity and a favorable recovery, and can be used to determine the amount of lead and mercury in carbonyl iron.