连续光源火焰原子吸收光谱法测定氧化镍中钴铜锌铁钙镁

采用盐酸溶解样品,选择Co 240.72nm、Cu 324.75nm、Zn 213.86nm、Fe 248.33nm、Ca 422.67nm、Mg 202.58nm作为分析谱线,钴、铜、锌、铁选择3个像素点,钙、镁选择9个像素点,建立了连续光源原子吸收光谱法(CS-AAS)同时测定氧化镍中的钴、铜、锌、铁、钙、镁的方法。实验表明:在100mL测定液中加入2mL 200g/L氯化锶溶液,可消除测定介质(体积分数为2%的盐酸)对待测元素的影响;基体镍对测定的干扰可忽略。在优化的实验条件下,钴、铜、锌、铁、钙、镁的校准曲线相关系数均不低于0.999 0,且其方法检出限在0.002~0.092μg/mL之间。按照实验方法对氧化镍样品中钴、铜、锌、铁、钙、镁分别平行测定11次,钙和镁的测定值在0.1%~0.4%之间,其对应的相对标准偏差(RSD)不大于2%;钴、铜、锌、铁的测定值在0.003%~0.04%之间,其对应的相对标准偏差均小于10%。将实验方法应用于电真空镍光谱标准样品(该标样为氧化镍状态)中上述各元素的测定,结果与认定值基本一致。

Determination of cobalt,copper,zinc,iron,calcium and magnesium in nickel oxide by continuum source flame atomic absorption spectrometry

The nickel oxide sample was dissolved with hydrochloric acid. Co 240.72 nm, Cu 324.75 nm, Zn 213.86 nm, Fe 248.33 nm, Ca 422.67 nm and Mg 202.58 nm were used as the analytical lines. Three pixels were selected for cobalt, copper, zinc and iron, while nine were selected for calcium and magnesium. Consequently, a simultaneous determination method of cobalt, copper, zinc, iron, calcium and magnesium in nickel oxide was established by continuum source flame atomic absorption spectrometry(CS-AAS). The results showed that the influence of determination medium (hydrochloric acid with volume fraction of 2%) on test elements could be eliminated by adding 2 mL of 200 g/L strontium chloride solution into 100 mL of test solution. The interference of matrix nickel could be ignored. Under the optimized experimental conditions, the correlation coefficients of calibration curves for cobalt, copper, zinc, iron, calcium and magnesium were all not less than 0.999 0. The detection limits of method were between 0.002 μg/mL and 0.092 μg/mL. The content of cobalt, copper, zinc, iron, calcium and magnesium in nickel oxide sample was determined parallelly according to the experimental method for 11 times. The determination results of calcium and magnesium were between 0.1% and 0.4%, and the corresponding relative standard deviations (RSDs, n=11) were not more than 2%. The determination results of cobalt, copper, zinc and iron were between 0.003% and 0.04%, and the corresponding RSDs were less than 10%. The proposed method was applied for the determination of the above elements in nickel alloy certified reference materials of electron tube for spectral analysis (exist in nickel oxide state). The results were consistent with the certified values.