扫描电镜-能谱分析在四川西部某锂矿石铌钽元素赋存状态研究上的应用  

Application of SEM and EDS to Study the Occurrence of Niobium and Tantalum from Lithium Ore in West Sichuan

作　　者：朱汇派 费光春[2] 谭华 蔡云华 陈宵杰 陈金香 ZHU Huipai;FEI Guangchun;TAN Hua;CAI Yunhua;CHEN Xiaojie;CHEN Jinxiang(Geochemistry Exploration Team of the Sichuan Bureau of Geology and Mineral Resources,Deyang 618000,Sichuan,China;College of Earth Science,Key Laboratory of Tectonic Controls on Mineralization and Hydrocarbon Accumulation,Ministry of Natural Resources,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]四川省地质矿产勘查开发局化探队,四川德阳618000 [2]成都理工大学地球科学学院,自然资源部构造成矿成藏重点实验室,成都610059

出　　处：《有色金属（选矿部分）》2023年第5期16-21,41,共7页Nonferrous Metals（Mineral Processing Section）

基　　金：四川省科技厅应用基础研究项目(2021yj0309);四川省地质矿产勘查开发局化探队科研项目(HTKYD2022005)。

摘　　要：花岗伟晶岩中的铌钽作为一种重要的战略资源,具有重要的开发利用价值。以四川西部某花岗伟晶岩型锂矿石为研究对象,在矿石多元素化学分析和显微镜下观察的基础上,开展扫描电镜背散射图像、能谱点和面扫描分析,对矿石中的铌钽赋存状态开展了研究。结果表明,矿石中Nb_(2)O_(5)含量为0.009%,Ta_(2)O_(5)含量为0.004%。铌钽矿物背散射图像(BSE)为灰黑色时Nb含量高,为灰白色时Ta成分较高。铌和钽元素以独立矿物的形式富集在铌钽矿物中,少量以类质同象的形式赋存在锡石和白云母中。铌钽矿物主要包括铌锰矿和钽锰矿,主要以粒间分布以及包裹体分布两种嵌布形式分布于矿石中。上述研究结果表明,扫描电镜背散射图像和能谱面扫描能有效的指示成分不均一的铌钽矿物铌和钽元素的赋存状态,以类质同象形式赋存在矿物中的微量铌和钽元素的分析需要借助高精度的LA-ICP-MS方法。As an important strategic resource,niobium and tantalum resources in granite pegmatite are of great value for development and utilization.Taking a rare metal pegmatite type lithium ore in western Sichuan as a case study,on the basis of chemical analysis and microscope observation,scanning electron microscope and energy spectrum analysis,the occurrence state of niobium and tantalum in the ore are studied.The results show that the content of Nb_(2)O_(5)in the ore is 0.009%,and the content of Ta2O5is 0.004%.Niobium and tantalum mainly occurs in niobium-tantalum minerals as independent minerals,and a small amount occurs in cassiterite and muscovite in the form of isomorphism.The BSE image of niobium and tantalum minerals from the ore is gray and black with high Nb content,while the BSE image is gray and white with high Ta composition.Niobium-tantalum minerals mainly include columbite-Mn and tantalum-Mn,intergranular distribution and inclusion distribution are two main distribution types.BSE and EDS can effectively explore the occurrence state of niobium and tantalum elements of niobium and tantalum minerals with heterogeneous composition.The analysis of trace elements of niobium and tantalum contents in the form of homogeneous in-phase in minerals requires the high-precision LA-ICP-MS method.

关 键 词：赋存状态 锂矿石 铌钽矿物 能谱扫面 背散射图像 

分 类 号：TD91[矿业工程—选矿]