碱熔-电感耦合等离子体质谱法测定铍矿石中的铍和锡

Determination of Beryllium and Tin in Beryllium Ore by Inductively Coupled Plasma-Mass Spectrometry with Alkali Fusion

稀有金属矿物组成复杂,且矿物成分多样化,现有质谱方法对铍的测定以地质样品中或矿石样品中的低含量铍分析为主,也很少应用于分析铍矿石中伴生的难溶锡元素。本文以新疆大红柳滩高品位铍矿石并伴生较高含量锡元素的样品为研究对象,建立了铍矿石中难溶元素铍和锡同时测定的方法。利用高温熔融态过氧化钠强的复分解能力,将矿物中的坚固晶格破坏,使目标物转换为易溶盐被提取,通过10倍稀释降低样品基体盐分含量,保证长期测量的稳定性RSD低于5%,并对校准曲线进行基体匹配,以电感耦合等离子体质谱(ICP-MS)测定,铍和锡在5~2000ng/mL浓度范围内线性关系良好,相关系数均大于0.999,检出限为铍0.20μg/g、锡0.17μg/g;测量精密度高(RSD≤5%),测量上限为氧化铍5.6%,锡2%。本文方法线性范围宽,适合各种高品位铍矿石中铍和锡的分析。将建立的方法应用于分析新疆大红柳滩高品位铍矿等多金属稀有金属矿,氧化铍含量达到0.85%、锡含量达到0.078%的样品测量精密度良好;还适用于分析铍矿石中其他稀有元素锂铷铯铌钽和稀土元素。

Due to the complex composition of rare metal minerals and the diversity of mineral components,the existing mass spectrometry methods for the determination of beryllium mainly focus on the analysis of low content beryllium in geological samples or ore samples,and rarely study and analyze the associated insoluble tin element in beryllium ores.A method for simultaneous determination of insoluble elements beryllium and tin in beryllium ores with high grade beryllium ore and associated high tin content in Dahongliutan,Xinjiang was established.The strong complex decomposition ability of molten sodium peroxide at high temperature was used to destroy the solid crystal lattice in the mineral,so that the target object was converted into soluble salt and extracted.The salt content of the sample matrix was reduced by 10 times dilution to ensure the long-term measurement stability of RSD below 5%.The matrix matching of the calibration curve was performed and determined by inductively coupled plasma-mass spectrometry.The linear relationship between beryllium and tin was good in the concentration range of 5−2000ng/mL,and the correlation coefficients were greater than 0.999.The detection limits of beryllium and tin were 0.20μg/g and 0.17μg/g respectively.High measurement stability(RSD)≤5%,the upper limit of measurement of beryllium oxide was 5.6%,tin was 2%.Compared with the existing methods,this method has a wide linear range and is suitable for the analysis of beryllium and tin in various high grade beryllium ores.The established method was applied to polymetallic rare metals such as high-grade beryllium ore in Dahongliutan,Xinjiang,and it was found that the precision of the samples with beryllium oxide content above 0.85%and tin content above 0.078%was good.This method is also suitable for the determination of other rare elements such as lithium,rubidium,cesium,niobium,tantalum and rare earth in beryllium ores.