辉光放电质谱法测定稀土氧化物中35种杂质元素  

Determination of 35 impurity elements in rare earth oxide by glow discharge mass spectrometry

作　　者：汤云腾 张其凯 袁晓红 宋立军 TANG Yunteng;ZHANG Qikai;YUAN Xiaohong;SONG Lijun(Xiamen Institute of Rare Earth Materials,Haixi Institutes,Chinese Academy of Sciences,Xiamen 361021,China)

机构地区：[1]中国科学院海西研究院厦门稀土材料研究中心,福建厦门361021

出　　处：《冶金分析》2023年第6期38-46,共9页Metallurgical Analysis

摘　　要：稀土元素是重要的战略资源,对稀土氧化物中杂质元素含量的分析日益受到重视。用高纯金属铟做导电介质,将稀土氧化物样品压制在铟片上,选择合适的同位素及分辨率,建立了辉光放电质谱法(GDMS)测定稀土氧化物中35种杂质元素的方法。以氧化镧样品为试验对象对仪器工作参数进行了优化,确定条件如下所示:放电电流40 mA;气体流量330 mL/min;先对铟片进行20 min的预溅射以去除其表面污染,然后添加稀土氧化物样品进行12 min预溅射后再进行测定。其他稀土氧化物的测试参数可参考氧化镧的条件进行微调。对制样条件进行了优化,确定取样量为10 mg,及全覆盖制样方式。各元素的方法检出限小于0.05μg/g,定量限小于0.1μg/g。将实验方法应用于氧化镧、氧化铈、氧化镨、氧化钕4种稀土氧化物样品中35种杂质元素含量的测定,测定结果的相对标准偏差(RSD,n=6)均小于25%。采用其他方法进行比对,结果表明,实验方法测定氧化镧样品中稀土元素的结果与铜粉混合压片-辉光放电质谱法基本一致;实验方法测定氧化镧样品中各杂质元素的结果与电感耦合等离子体质谱法(ICP-MS)基本一致。方法弥补了高纯铜粉较难获得和ICP-MS前处理繁琐的不足。Rare earth elements are important strategic resources,thus the determination of impurity elements in rare earth oxide has been paid more and more attention.The rare earth oxide sample was pressed on indium sheet with high purity metal indium as conductive medium,and a new method for determination of 35 impurity elements in rare earth oxides was established by glow discharge mass spectrometry(GDMS)with appropriate isotopes and resolution.The lanthanum oxide sample was used as the test object to optimize the instrument working parameters,and the conditions were obtained as follows:the discharge current was 40 mA,the gas flow rate was 330 mL/min,the indium sheet was presputtered for 20 min to remove its surface contamination,the rare earth oxide sample was added and presputtered for 12 min before determination.The test parameters of other rare earth oxides could be fine-tuned by referring to lanthanum oxide conditions.The sample preparation conditions were optimized.The sample mass of 10 mg was selected,and the sample preparation method was full coverage.The limits of detection for elements were all less than 0.05μg/g,and the limits of quantification were all less than 0.1μg/g.The proposed method was applied to determination of 35 impurity elements in samples of lanthanum oxide,cerium oxide,praseodymium oxide and neodymium oxide.The relative standard deviations(RSD,n=6)of determination result were all less than 25%.Method comparison test was conducted.The determination results of rare earth elements in lanthanum oxide sample by proposed method were basically consistent with those obtained by copper powder pellet-glow discharge mass spectrometry.The determination results of impurity elements in lanthanum oxide sample were all in good agreement with those obtained by inductively coupled plasma mass spectrometry(ICP-MS).This method makes up the shortcomings of difficult to obtain high purity copper powder and complicated pretreatment by ICP-MS.

关 键 词：稀土氧化物 辉光放电质谱法(GDMS) 杂质元素 铟片 氧化镧 氧化铈 氧化镨 氧化钕 

分 类 号：O657.31[理学—分析化学] TF031[理学—化学]