摘要
针对四极杆ICP-MS法无法测定高纯稀土中的痕量杂质铁元素的问题,建立了电感耦合等离子体串联质谱(ICP-MS/MS)分析方法。采用氧气反应池的串联质谱技术,经优化仪器参数,确定O_2流量为2.0 mL/min,基体进样浓度为3.00 g/L,以内标In校正;同时,选择丰度为91.68%的同位素^(56)Fe^+离子为分析目标,并计算出八级杆偏置负压V_(oct)=-10 eV时产生的质心碰撞能量E_(cm)高于^(56)Fe^(16)O^+反应焓ΔHr的3倍,提供的动能可确保利用O_2碰撞反应与^(56)Fe^+生成目标产物^(56)Fe^(16)O^+;再设置Q_1=56/Q_2=72,有效克服^(40)Ar^(16)O^+、^(40)Ca^(16)O^+、^(37)Cl^(18)OH^+等多原子离子的质谱干扰,并准确测定了15种高纯稀土氧化物以及Ce、Nd、Y、Pr-Nd 4种高纯稀土中痕量杂质Fe的含量。在选定的分析条件下,校准曲线的线性相关系数大于0.9999,方法检出限(L_0)为68μg/g,精密度(RSD,n=11)为2.1%～4.3%,回收率为95%～105%。本方法操作简便、环保,适合高纯稀土及其氧化物中痕量铁的快速测定。
Because inductively coupled plasma mass spectrometry(ICP-MS)could not be used for determination of trace Fe in high purity rare earths,an inductively coupled plasma-tandem mass spectrometry(ICP-MS/MS)method was proposed.The mass spectral technique based on the oxygen reaction cell was used to optimize the instrument parameters,the flow rate of O2 was adjusted to 2.0mL/min,and the matrix injection concentration was determined to be 3.00g/L,as well as the internal standard In was used for the calibration.Then,the isotope 56Fe^+ ion with abundance of 91.68%was selected as the analysis target.With Q1=56/Q2=72,the collision reaction of O2 with 56Fe^+ was carried out to generate the target product of 56Fe16O^+,which performed effectively to eliminate the mass spectrum interference of polyatomic ion of 40Ar16O^+,40Ca16O^+ and 37Cl18OH^+.So that it could accurately determine the trace impurities of Fe content in 15 kinds of high purity rare earth oxide and 4 kinds of high purity rare earth metals of cerium,neodymium,yttrium,and praseodymium-neodymium.According to the selected analysis conditions,the linear correlation coefficient of the calibration curve was greater than 0.9999,the detection limit was 68μg/g,the relative standard deviations(RSD,n=11)were 2.1%-4.3%,and the recoveries were 95%-105%.This method is simple and environmentally friendly,and suitable for the rapid determination of trace of Fe in high purity rare earth metals and their oxides.
作者
陈文
樊小伟
郭才女
宋旭东
刘宜强
徐娜
CHEN Wen;FAN Xiao-Wei;GUO Cai-Nv;SONG Xu-Dong;LIU Yi-Qiang;XU Na(National Tungsten & Rare-earth Product Quality Supervision Testing Center,Ganzhou 341000,China;Faculty of Materials Science and Engineering,Jiangxi University of Science and Technique,Ganzhou 341000,China;Jiangxi South Rare Earth Hi-Tech Co.,Ltd,Ganzhou 341000,China)
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2019年第3期403-409,共7页
Chinese Journal of Analytical Chemistry
基金
国家自然科学基金项目(No.21471070)资助~~
关键词
电感耦合等离子体串联质谱
高纯稀土
铁
多原子离子干扰
Inductively coupled plasma-tandem mass spectrometry
High purity rare earths
Iron
Polyatomic ion interference
