粉末压片制样-X射线荧光光谱法测定锂云母中铷、铯及主量组分

锂云母中铷、铯及主量元素的分析一般采用化学湿法,前处理过程复杂。实验采用粉末压片制样-X射线荧光光谱法(XRF)对锂云母中铷、铯及主量组分(二氧化硅、三氧化二铝、全铁、氧化钙、氧化钾、氧化钠)进行了测定。采用锂矿石标准物质和人工合成校准样品制作校准曲线,各组分的均方根为0.0042~0.49。校准曲线采用经验系数和康普顿散射线内标法校正组分间的吸收-增强效应,方法的检出限为3.1~188μg/g。按照实验方法测定锂矿石标准物质GBW 07152中铷、铯及主量组分,结果的相对标准偏差(RSD,n=10)在0.31%~5.0%之间。实验方法用于测定人工合成校准样品(未参与校准曲线的绘制)中铷、铯及主量组分,测定值与理论值吻合良好;测定2个锂云母实际样品中铷、铯及主量组分,测定结果与电感耦合等离子体原子发射光谱法(ICP-AES)的测定值相符。

Determination of rubidium,cesium and major components in lithium mica by X-ray fluorescence spectrometry with pressed powder pellet

The contents of rubidium, cesium and major components in lithium mica are generally analyzed by wet chemical methods, but the pretreatment process is complicated. The contents of rubidium, cesium and major components (including silicon dioxide, aluminum oxide, total iron, calcium oxide, potassium oxide and sodium oxide) in lithium mica were determined by X-ray fluorescence spectrometry (XRF) with pressed powder pellet. The calibration curves were prepared using lithium ore reference materials and artificially synthesized calibration samples. The root mean square of each component was in range of 0.0042-0.49. The calibration curve was treated by the empirical coefficient method and the Compton scattering line internal standard method to correct the absorption-enhancement effect among components. The detection limit was 3.1-188μg/g. The proposed method was applied for the determination of rubidium, cesium and major components in certified reference materials of lithium ore (GBW 07152). The relative standard deviations (RSD, n=10) were between 0.31% and 5.0%. The contents of rubidium, cesium and major components in artificially synthesized calibration samples (which were not participated in the preparation of calibration curves), and the found results were in good agreement with the theoretical values. The experimental method was applied for the determination of rubidium, cesium and major components in actual samples of lithium mica, and the found results were consistent with those obtained by inductively coupled plasma atomic emission spectrometry (ICP-AES).