火焰原子吸收光谱法测定铜磁铁矿中铜

采用15mL盐酸、5mL硝酸、3mL氢氟酸和5mL高氯酸分解试样,以5%(V/V)的高氯酸为测定介质,建立了火焰原子吸收光谱法(FAAS)测定铜磁铁矿中0.1%~2%铜的方法。干扰试验表明,铜磁铁矿中杂质元素在最大量存在的条件下不干扰铜的测定。在选定的实验条件下,铜校准曲线的相关系数为0.999 1,方法检出限为0.017μg/mL。将实验方法应用于5个铜磁铁矿样品中铜的测定,测得结果与电感耦合等离子体原子发射光谱法(ICPAES)基本一致,相对标准偏差(RSD,n=11)在1.2%~3.7%之间,加标回收率在96%~104%之间。分别在7家实验室采用实验方法进行测定,结果显示,实验方法的再现性限(R)在0.020%~0.118%之间。

Determination of copper in copper magnetite by flame atomic absorption spectrometry

After copper magnetite sample was decomposed with 15 mL of hydrochloric acid, 5 mL of nitric acid, 3 mL of hydrofluoric acid and 5 mL of perchloric acid,a determination method of copper (0.1%-2%) in copper magnetite by flame atomic absorption spectrometry(FAAS) was established with 5%(V/V) perchloric acid as determination medium. The interference tests indicated that the maximum contents of impurities in copper magnetite had no interference with the determination of copper. Under the selected experimental conditions, the correlation coefficient of calibration curve for copper was 0.999 1. The detection limit of method was 0.017 μg/mL. The proposed method was applied for the determination of copper in five copper magnetite samples, and the results were basically consistent with those obtained by inductively coupled plasma atomic emission spectrometry (ICP-AES). The relative standard deviations (RSD, n=11) were between 1.2% and 3.7%. The recoveries were between 96% and 104%. The proposed method was tested in seven laboratories, and the reproducibility limit (R) was in range of 0.020%-0.118%.