氟化氢铵焙烧分离-碱熔-电感耦合等离子体质谱(ICP-MS)法测定高硅矿物中稀土元素及铌、钽  

Determination of Niobium,Tantalum and Rare Earth Elements in High-silicon Minerals by ICP-MS with Ammonium Bifluoride Roasting Separation-Alkali Fusion

作　　者：韩亚军 王啸 甘黎明 冯博鑫 李荣华 王佳明 宋永涛 HAN Yajun;WANG Xiao;GAN Liming;FENG Boxin;LI Ronghua;WANG Jiaming;SONG Yongtao(Xi'an Center of Mineral Resources Survey Center,China Geological Survey,Xi'an,Shaanxi 710100,China;Technology Innovation Center for Gold Ore Exploration,China Geological Survey,Xi'an,Shaanxi 710100,China)

机构地区：[1]中国地质调查局西安矿产资源调查中心,西安710100 [2]中国地质调查局金矿勘察技术创新中心,西安710100

出　　处：《中国无机分析化学》2025年第4期500-505,共6页Chinese Journal of Inorganic Analytical Chemistry

基　　金：战略性矿产勘查岩矿测试技术支撑项目(DD20243334)。

摘　　要：稀土元素及铌、钽矿常分布在花岗岩矿床,该矿床主要成分为二氧化硅和硅酸盐,酸溶很难溶解完全,利用碱熔可有效将样品打开,但在过滤分离时,由于硅含量高,溶液黏度大,很难将硅分离干净,易形成硅胶沉淀吸附铌、钽及稀土元素,分析结果难以控制。针对花岗岩硅含量高的特性,建立了氟化氢铵焙烧分离-碱熔-电感耦合等离子体质谱(ICP-MS)法测定矿物中的稀土元素及铌、钽的方法,样品加入5.0 g氟化氢铵焙烧1.5 h,碱熔浸取后过滤,用稀盐酸冲洗溶解待测元素,加入酒石酸防止铌、钽的水解,定容后上机测试,消除了高硅对分析结果的影响,并用国家一级标准物岩石、土壤、水系沉积物质对方法进行验证,方法检出限在0.001~0.003μg/g,均小于DZ/T 0258-2014《多目标区域地球化学调查规范(1∶250000)》中对分析方法检出限的要求,测定结果与标准值一致,相对标准偏差(RSD)≤3%。较不分离硅测定结果的准确度、精密度均有大幅提升,适用于花岗岩等高硅矿床中稀土元素及铌、钽的分析,方法操作较为简便,结果准确可靠,值得推广。Rare earth elements,niobium and tantalum ores are often distributed in granite deposits.The main components of this deposit are silica and silicates,which are difficult to completely dissolve in acid.Alkali fusion can effectively open the sample.However,during filtration and separation,due to the high silicon content and high solution viscosity,it is difficult to separate silicon completely,and it is easy to form silica gel precipitation to adsorb niobium,tantalum and rare earth elements.The analysis results are difficult to control.In response to the high silicon content in granite,the method consisting of ammonium hydrogen fluoride roasting separation,alkali fusion and inductively coupled plasma mass spectrometry(ICP-MS)was established to determine rare earth elements,niobium and tantalum in minerals.The sample was roasted for 1.5 hours after adding 5.0 g of ammonium bifluoride.Through alkali fusion leaching,the sample was filtered and washed with dilute hydrochloric acid to dissolve the elements to be tested.Tartaric acid was added to prevent the hydrolysis of niobium and tantalum.Machine testing at a fixed volume was conducted to eliminate the influence of high silicon on the analysis results.The method was validated using national first-class standard materials for rocks,soil,and water sedimentary materials,with a relative standard deviation(RSD)of less than or equal to 3%.The detection limits of the method were all lower than the requirements of the detection limits of the analysis method in the DZ/T 0258-2014 Multi target Regional Geochemical Survey Specification(1∶250000),and the measurement results were consistent with the standard values.Compared to the non-separation of silicon,the accuracy and precision of this method have been greatly improved,making it suitable for the analysis of rare earth elements and niobium and tantalum in high silicon deposits such as granite.The method is easy to operate,with accurate and reliable results,and is worth promoting.

关 键 词：ICP-MS 氟化氢铵 碱熔 二氧化硅 稀土元素 

分 类 号：O657.63[理学—分析化学]