电感耦合等离子体质谱法测定钢铁及合金中镧、铈、镨、钕、钐

摘要

A method was developed for simultaneous determination of La, Ce, Pr, Nd, Sm in iron, steel and alloy by inductively coupled plasma mass spectrometry (ICP-MS) after sample dissolution with diluent aqua regia. The optimized operation parameters were obtained. The spectral interference was eliminated by selecting appropriate analytical isotopes. Standard addition method was used for calibration curve. The results showed that the matrix effect was negligible when the concentration of Fe matrix was not higher than 1 mg/mL. Therefore, the matrix effect could be eliminated by controlling its concentration as 1 mg/mL. The long-term shift of analytical signals was compensated by selecting In as internal standard element. The detection limits were 0. 023 ng/mL for La, 0. 021 ng/mL for Ce, 0. 025 ng/mL for Pr, 0. 075 ng/mL for Nd, and 0. 057 ng/mL for Sm, respectively. The proposed method has been applied in the determination of actual samples. The results were accordance with those obtained by inductively coupled plasma atomic emission spectrometry(ICP-AES), and the relative standard deviations were no more than 11. 8%.%采用稀王水溶样,建立了电感耦合等离子体质谱法(ICP-MS)同时测定钢铁及合金中镧、铈、镨、钕、钐含量的分析方法.确定了最佳仪器工作条件,选择适合的同位素消除了质谱干扰,选用标准加入法建立了校准曲线.实验表明,铁基体浓度不大于1 mg/mL时,基体效应不太显著,因此通过控制基体浓度为1 mg/mL消除了基体效应.选择In为内标元素补偿了长期分析信号的漂移.各元素检出限分别为La 0.023 ng/mL,Ce 0.021 ng/mL,Pr 0.025ng/mL,Nd 0.075 ng/mL,Sm 0.057 ng/mL.将方法应用于实际样品分析,测定值与电感耦合等离子体原子发射光谱法(ICP-AES)结果一致,相对标准偏差不大于11.8％.