饮用水中镁的火焰原子发射光谱测定法

Determination of Magnesium in Drinking Water by Flame Atomic Emission Spectrometry

目的 探讨乙炔-空气火焰原子发射法测定饮用水中镁。方法 以盐酸为介质,镧盐为掩蔽剂,直接采用乙炔-空气原子发射法测定饮用水中镁。结果 镁浓度在5～200μg/ml范围内与火焰发射光谱强度呈线性相关,回归方程A=0.000 87C+0.001,r=0.992 2。最低检测浓度为5.0μg/ml,样品加标回收率为101.8％～107.5％,相对标准偏差（RSD）≤3.3％。常见共存离子K、Na、Ca、Zn、Fe、Mn、Cd、Ph、Cu在一定浓度内不干扰测定。结论 乙炔-空气火焰原子发射光谱法可用于测定饮用水中镁。

ve To explore a method for determination of magnesium in drinking water by air-acetylene flame atomic emission spectrometry. Methods The content of magnesium in drinking water was directly determined by air-acetylene flame atomic emission spectrometry using hydrochloric acid as media and lanthanum solution as masking agent. Results The concentrations of magnesium in drinking water were possitively correlated with the intensities of flame atomic emission spectrum in the range of 5~200μg/ml with a regression equation of A = 0.000 87C+0.0019(r=0.992 2). The detection limit was 5.0μg/ml. The recovery rates of a standard material added-water samples were 101.8% ~ 107.5% . The relative standard deviation was not more than 3.3% . The com-monly coexisting ions with a certain concentrations, such as K, Na, Ca, Zn, Fe, Mn, Cd,Pb and Cu, didn't interfere the determination of magnesium in water sample. Conclusion This method could be applied to determination of magne-sium in drinking water.