电感耦合等离子体原子发射光谱法测定保护渣中氧化钾和氧化钠

保护渣试样经盐酸、硝酸、氢氟酸酸化溶解,高氯酸冒烟后的残渣用盐酸溶解,选择766.485 nm和589.586 nm的光谱线分别作为钾和钠的分析线,在体积分数5%盐酸介质中用电感耦合等离子体原子发射光谱法(ICP-AES)测定试液中氧化钾和氧化钠含量。方法的检出限,对于钾为0.001 μg/mL,对于钠为0.005 μg/mL。基体对钾、钠测定的干扰程度较小,元素间基本无干扰,可以直接用氧化钾、氧化钠标准溶液绘制校准曲线。方法用于氧化钾和氧化钠含量不同的保护渣样品分析,氧化钾和氧化钠测定结果与化学法测定结果相符,无显著性差异,相对标准偏差(RSD)小于2.0%,可以满足保护渣试样成分的测定要求。

Determination of potassium oxide and sodium oxide in mold flux by inductively coupled plasma atomic emission spectrometry

The mold flux sample was dissolved in hydrochloric acid, nitric acid and hydrofluoric acid. After fumes of perchloric acid were evoluved, the residue was dissolved with hydrochloric acid. The spectral lines of 766.485 nm and 589.586 nm were selected to analyze potassium and sodium, respectively. The content of potassium oxide and sodium oxide in testing solution was determined in 5 % hydrochloric acid medium by inductively coupled plasma atomic emission spectrometry (ICP-AES). The detection limit was 0.001 μg/mL and 0.005 μg/mL for potassium and sodium, respectively. The matrix had little interference in the determination of potassium and sodium. There was no interference among elements. Therefore, the calibration curve could be directly plotted using the standard solution of potassium oxide and sodium oxide. The proposed method was applied to the analysis of mold flux samples with various contents of potassium oxide and sodium oxide. The found results of potassium oxide and sodium oxide were consistent with those obtained by chemical method without significant difference. The relative standard deviation (RSD) was less than 2.0%, which could meet the determination requirements of components in mold flux sample.