醋酸预处理-熔融制样-X射线荧光光谱法测定重晶石中主要组分  

Determination of main components in barite by X-ray fluorescence spectrometry with fusion sample preparation after acetic acid pretreatment

作　　者：李大勇[1] 王士魁 王亮[1] 张周位 LI Dayong;WANG Shikui;WANG Liang;ZHANG Zhouwei(Guizhou Central Laboratory of Geology and Mineral Resources,Guiyang 550018,China;No.113 Geological Party,Guizhou Bureau of Geology and Mineral Exploration&Development,Liupanshui 553001,China)

机构地区：[1]贵州省地质矿产中心实验室,贵州贵阳550018 [2]贵州省地矿局一一三地质大队,贵州六盘水553001

出　　处：《冶金分析》2023年第3期27-33,共7页Metallurgical Analysis

基　　金：贵州省地质矿产勘查开发局地质科研项目(黔地矿科合[2020]33号)。

摘　　要：准确测定重晶石的主要组分对重晶石资源后续的开发与利用具有重要意义。由于X射线荧光光谱法(XRF)测定BaSO_(4)、SrSO_(4)的结果是通过测定Ba、Sr分析谱线后换算得到的,故样品中的BaCO_(3)、SrCO_(3)会干扰BaSO_(4)和SrSO_(4)的测定。实验先采用醋酸预处理分离样品中的碳酸盐类成分,再采用XRF测定,成功避免了BaCO_(3)、SrCO_(3)对BaSO_(4)和SrSO_(4)测定的干扰。同时,将经过醋酸预处理后的滤渣灼烧后称重,计算样品损失量,通过补加与样品损失相等质量的混合熔剂的方法来补正因醋酸预处理及灼烧带来的样品质量损失,采用四硼酸锂-偏硼酸锂混合熔剂熔融制样,实现了XRF对重晶石中BaSO_(4)、Al_(2)O_(3)、SiO_(2)、Fe、SrSO_(4)共5种组分的同时测定。选用各组分含量呈一定阶梯的重晶石国家标准物质及贵州省级标准物质绘制校准曲线,校准曲线的决定系数不小于0.9998,BaSO_(4)方法检出限为0.128%,其余组分的检出限范围为0.004%~0.029%。将实验方法应用于重晶石样品分析,结果表明,各组分测定值大于5%时,相对标准偏差RSD≤0.2%;各组分测定值不大于5%时,RSD≤2.0%。相对误差(RE)均小于地质矿产实验室测试质量管理规范DZ/T 0130—2006要求的允许限。It is of great significance to determine accurately the main components in barite for the subsequent development and utilization of barite resources.As the determination results of BaSO_(4) and SrSO_(4) by X-ray fluorescence spectrometry(XRF)are converted from the determination results of the analysis spectral lines of Ba and Sr,BaCO_(3) and SrCO_(3) in the sample will interfere with the determination of BaSO_(4) and BaSO_(4).After the carbonate components in the sample were separated by acetic acid pretreatment,the sample was determined by XRF,which successfully avoided the interference of BaCO_(3) and SrCO_(3) with BaSO_(4) and SrSO_(4).At the same time,the filter slag after acetic acid pretreatment was burned and weighed to calculate the sample loss.The sample mass loss caused by acetic acid pretreatment and burning was compensated by adding mixed flux with the same mass as the sample loss.The sample pellet was prepared by fusion sample preparation with mixed flux of lithium tetraborate and lithium metaborate.Consequently,a method for simultaneous determination of 5 components including BaSO_(4),Al_(2)O_(3),SiO_(2),Fe and BaSO_(4) in barite was realized by XRF.The national reference material and Guizhou Provincial reference material of barite with a certain level of component content were selected to prepare the calibration curve.The determination coefficients of calibration curves were all not less than 0.9998.The detection limit of BaSO_(4) was 0.128%,and detection limits for other components were in range of 0.004%-0.029%.The proposed method was applied to the analysis of barite samples.The results showed that the relative standard deviations(RSD)were not more than 0.2%when the determination results were greater than 5%.The relative standard deviations were not more than 2.0%when the determination results were not more than 5%.The relative errors(RE)were all less than the allowable limits specified in DZ/T 0130-2006 of the specification of testing quality management for geological laboratories.

关 键 词：醋酸预处理 熔融制样 X射线荧光光谱法(XRF) 重晶石 硫酸钡 硫酸锶 

分 类 号：O657.34[理学—分析化学]