熔融制样X射线荧光光谱法快速测定铌精矿中10种元素

Rapid determination of 10 elements in niobium concentrate by X-Ray fluorescence spectrometry with fusion sample preparation

采用高温熔融制样方式将铌精矿制备成均匀稳定的玻璃片,利用X射线荧光光谱法测定铌精矿中铌、硅、钙、镁、钛、磷、锶、锰、钡、钍10种元素的含量。将样品与四硼酸锂-偏硼酸锂混合溶剂(质量比67∶33)按照1∶14的质量比混合,加入30 g/L溴化锂溶液0.2 mL,在全自动熔样机上于1050℃熔融8 min,摇摆6 min,静置冷却脱模后得到测定玻璃样片。采用人工配制标准样品的方法建立标准工作曲线,以经验系数法校正谱线重叠效应,用理论α系数法校正基体效应,两个不同含量水平铌精矿样品测定结果的相对标准偏差为0.23%~3.91%(n=9),该方法与化学法测定值基本一致。该方法可实现实际铌精矿样品中10种主次量元素的快速批量日常检测。

High-temperature melting sample preparation was used to prepare uniform and stable glass sheets,and the contents major and minor elements in niobium concentrate such as niobium,silicon,calcium,magnesium,titanium,phosphorus,strontium,manganese,barium and thorium in niobium concentrate were determined by X-ray fluorescence spectrometry.The sample was mixed with lithium tetraborate-lithium metaborate mixed solvent(mass ratio was 67:33)according to the mass ratio of 1:14,and 0.2 mL of 30 g/L lithium bromide solution was added.The sample was melted at 1050℃for 8 minutes in a fully automatic melting machine,shaken for 6 minutes,and then stood for cooling and demolding to obtain the glass sample.The working curve was established by manually preparing standard samples.Spectral line overlap was corrected by empirical coefficient method.Matrix effect was corrected by theoreticalαcoefficient method.Repeatability experiments and accuracy experiments were carried out on the established working curve.For the precision experiments of two niobium concentrate samples with different content levels,the relative standard deviation of the detection results were 0.23%-3.91%(n=9),and the results determined by this method were basically consistent with those detected by chemical methods.The method can quickly and accurately determine 10 elements in niobium concentrate,and realize the rapid batch and accurate determination of multi-elements in niobium concentrate in daily practical samples.