敞口酸熔-电感耦合等离子体发射光谱法测定稀有多金属矿选矿样品中的铌钽和伴生元素

摘要

稀有多金属矿各类选矿样品中同一元素的含量相差较大,且同一样品中各元素的含量也有较大差异,如铌钽锂铍在尾矿和原矿中的含量只有几十至几百μg/g,而在精矿中的含量达到百分之几至百分之几十,伴生元素如钾、钠在不同样品中也有较大差异.应用敞口酸熔-电感耦合等离子体发射光谱法(ICP-OES)测定铌钽锂铍等元素通常采用三酸或四酸分解样品,多是测定尾矿、原矿及部分中矿样品中较低含量的铌钽锂铍,且同一测定体系中只测定了一种或两种元素.本文采用氢氟酸-硝酸-盐酸-高氯酸-硫酸分解样品,以3~4滴氢氟酸+5%硫酸+5%过氧化氢提取体系替代常规的有机酸(酒石酸等)提取体系,实现了应用ICP-OES同时测定稀有金属矿选矿试验各阶段产品中不同含量的铌钽锂铍钾钠铷铁钛等元素.各元素的谱线强度在0~500μg/mL浓度范围内呈良好的线性关系,相对标准偏差为0.37%~4.77%(n=6).该方法提高了选矿全流程样品中各类元素的分析效率,已在选冶试验流程样品分析中得到了应用.%The content of the same element in separate rare polymetallic ore processing samples is different,and the content of each element in the same sample is also different.For example,the content of niobium,tantalum, lithium,and beryllium in tailings and ore is only a few tens to several hundred μg/g,but in the concentrate these elements have contents of several percent to several percent and associated elements such as potassium and sodium in different samples are also quite different.Determination of niobium,tantalum,lithium,and beryllium by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES)commonly involves three acid or four acid decomposition of samples.This method was mostly used to determine the lower content of niobium,tantalum, lithium,and beryllium in tailings,ore and some of ore samples,and the same determination system only analyzes one or two elements.The niobium-tantalum polymetallic ore was dissolved with HF-HCl-HNO3-HClO3-H2 SO4 and extracted by 3 -4 drops of mixed hydrofluoric acid,5% sulfuric acid,and 5% hydrogen peroxide,instead of conventional organic acids (tartaric acid,etc ) extraction system,which makes it possible that simultaneous ICP-OES determination of niobium,tantalum,lithium,beryllium,potassium,sodium,rubidium,iron,titanium and other elements in different stages of rare metal ore beneficiation test products is possible.The spectral line intensity shows a good linear relationship when the concentration of elements is 0 -500 μg/mL.The relative standard deviation is 0.37% -4.77% (n =6).The method has improved the efficiency of the analysis of various elements in the whole process sample and has been applied in the sample analysis of the smelting process.