动能歧视(KED)-电感耦合等离子体质谱(ICP-MS)法测定贵州沉积型稀土矿中16种稀土元素  

Determination of 16 Rare Earth Elements in Sedimentary Rare Earth Ores in Guizhou Province by Inductively Coupled Plasma Mass Spectrometry with Kinetic Energy Discrimination(KED)

作　　者：张安丰 杨博为 王永鑫[1,2] 庞文品 毛珂 金修齐 ZHANG Anfeng;YANG Bowei;WANG Yongxin;PANG Wenpin;MAO Ke;JIN Xiuqi(Guizhou Central Laboratory of Geology and Mineral Resources,Guiyang,Guizhou 550018,China;Engineering Technology Innovation Center of Mineral Resources Explorations in Bedrock Zones,Ministry of Natural Resources,Guiyang,Guizhou 550081,China)

机构地区：[1]贵州省地质矿产中心实验室,贵阳550018 [2]自然资源部基岩区矿产资源勘查工程技术创新中心,贵阳550081

出　　处：《中国无机分析化学》2024年第5期575-585,共11页Chinese Journal of Inorganic Analytical Chemistry

基　　金：贵州省地质勘查专项资金项目(黔地矿函[2023]29号)。

摘　　要：贵州沉积型稀土矿主要含有高岭土-锐钛矿石等矿物,存在高含量Si、Al、Fe、Ti、Zr等难溶基体元素,采用高压密闭微波消解法处理难以将其完全溶解,易使测定结果偏低,需再次消解或进一步电热板敞开酸溶处理,方法耗时长,不利于大批量样品检测需求。同时电感耦合等离子体质谱(ICP-MS)法在测定稀土元素时存在基体和质谱干扰,影响了检测数据的准确性。采用过氧化钠熔融分解样品,熔融物冷却后引入三乙醇胺溶液,在碱性溶液中,大量基体元素与三乙醇胺形成稳定配合物,并与大量溶剂钠盐存于溶液中,稀土元素与Ca、Mg、Sr、Ba等留存于沉淀,经过滤,实现稀土元素与大量基体元素分离,随后沉淀用硝酸(1+1)复溶,并以^(103)Rh和^(185)Re为在线注入内标协同降低基体干扰;启用动能歧视(KED)模式以降低测定过程中潜在的质谱干扰。实验结果表明:高压密闭微波消解法消解液浑浊有残渣,溶矿耗时长,测试结果偏低,碱熔法酸化后溶液清亮透明,稀土元素测定值准确性高;采用10%三乙醇胺溶液提取能较大地降低基体干扰;启用KED模式可降低测定过程中的质谱干扰,且准确度优于STD模式;碱熔法检出限为0.008~0.049μg/g,测定下限为0.034~0.2μg/g,相对标准偏差RSD在0.78%~10.2%,相对误差RE在0.022%~13.5%。经实际样品验证,碱熔法较适用于贵州沉积性稀土矿中16种稀土元素的测定。Mineral in sedimentary rare earth ores in Guizhou province is mainly contain kaolin,anatase and other minerals,which containing high-content refractory matrix elements such as silicon,aluminum,ion,titanium and zirconium.It is hard to be completely dissolved with high-pressure microwave digestion method,which can easily lead to low measurement results.It is necessary to dissolved with the method again or digested with the open acid solution digestion method of electrothermal plate,which is time-consuming and unfavorable for the determination of a large batch of samples.At the same time,matrix effect and spectrometry interference are common in the determination of rare earth elements by inductively coupled plasma mass spectrometry(ICP-MS),affecting the accuracy of the determination result.The sample was molten and separated by sodium peroxide.The cooled melt was implanted into triethanolamine solution.In alkaline solution,plenty of matrix elements formed stable complexes with triethanolamine and were stored in the solution with a large amount of solvent sodium salts.Rare earth elements were coordinated with calcium,magnesium,strontium,barium and other elements and generated precipitation.After filtration,rare earth elements and matrix elements were separated from a large amount of matrix elements.Subsequently,the precipitation was redissolved in nitric acid(1+1)and internal standards of ^(103)Rh and ^(185)Re to were injected online to synergistically reduce matrix interference.Kinetic energy discrimination(KED)mode was performed to reduce potential mass spectrometry interference during the measurement process.The experimental results revealed that the digestion solution of high-pressure microwave digestion method was cloudy and full of debris;the process was time-consuming;the accuracy of determination result was lower.The digestion solution of alkaline dissolving method was clear and the accuracy of the rare earth elements determination result was high.Extracting elements with 10% triethanolamine solution could gr

关 键 词：稀土元素 三乙醇胺 动能歧视(KED)模式 碱熔法 高压密闭微波消解 电感耦合等离子体质谱 

分 类 号：O657.63[理学—分析化学]