无火焰原子吸收光谱法测定水中铝含量的不确定度评定

Evaluation of Uncertainty in Determination of Aluminum Content in Water by Flameless Atomic Absorption Spectrometry

目的:建立无火焰原子吸收法测定水中铝含量的不确定度评定方法。方法:根据《测量不确定度的评定与表示》(JJF 1059.1—2012)和《生活饮用水标准检验方法 金属指标》(GB/T 5750.6—2006)铝第三法无火焰原子吸收光谱法,水样经酸化后注入原子化器测定铝含量,并建立无火焰原子吸收法测定水中铝含量不确定度评定的数学模型,分析检测过程中不确定度的主要来源。结果:水中铝含量为(0.031±0.002) mg·L(k=2)。结论:影响水中铝含量测定的不确定度来源主要是样品的重复性测定和标准溶液的配制过程。

Objective: To establish an uncertainty evaluation method for the determination of aluminum in water by flameless atomic absorption spectrometry. Method: According to JJF 1059.1—2012 and GB/T 5750.6—2006, the water sample was acidified and then injected into the atomizer to determine the aluminum content, and a mathematical model for the uncertainty evaluation of the determination of aluminum content in water by flameless atomic absorption was established.And the main sources of uncertainty in the detection process were analyzed. Result: The aluminum content in water was(0.031 ± 0.002) mg·L(k=2). Conclusion: The main sources of uncertainty affecting the determination of aluminum content in water are the repeatability of sample determination and the preparation process of standard solution.