电感耦合等离子体串联质谱法测定高纯稀土中铁的含量  

Determination of Iron Content in High Purity Rare Earth by Inductively Coupled Plasma-Tandem Mass Spectrometry

作　　者：陈文 樊小伟 郭才女[3] 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)

机构地区：[1]国家钨与稀土产品质量监督检验中心,赣州341000 [2]江西理工大学材料与工程学院,赣州341000 [3]江西南方稀土高技术股份有限公司,赣州341000

出　　处：《分析化学》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~~

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.

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 

分 类 号：O657.63[理学—分析化学]