高灵敏度单波长激发能量色散X射线荧光光谱法测定铜精矿中16种组分

铜精矿技术条件中要求的组分覆盖范围从主量、常量、微量到痕量,要使用一种检测技术同时测定这些组分是铜精矿测定的难题。单波长激发能量色散X射线荧光光谱仪,采用双曲弯晶全聚焦技术,将X射线连续谱单色化,降低了连续谱背景,改善检出限,提高灵敏度,对组分的检测范围可覆盖主量到痕量。实验基于高灵敏度单波长激发能量色散X射线荧光光谱法(HS-EDXRF)结合快速基本参数法建立了铜精矿中主量组分Cu、S、Fe、SiO₂,常量组分CaO、MgO、Al₂O₃,微量和痕量组分Zn、Ni、Cr、Pb、Sb、Cl、Ag、As、Bi等16种组分的分析方法。采用实验方法测定铜精矿样品,结果与标准方法或经典分析方法结果对比,无显著性差异(t_0.05,82值均小于1.98)。此外,主量组分Cu、S、Fe、SiO₂测定结果的相对标准偏差(RSD,n=7)不大于0.70%,常量组分CaO、MgO、Al₂O₃的RSD小于1.6%,微量组分Zn、Ni、Cr、Pb、Sb、Cl的RSD不大于3.3%,痕量组分Ag、As、Bi等的RSD均小于10%。方法可满足铜冶炼工艺对铜精矿中16种组分的检测需求。

Determination of sixteen components in copper concentrate by high sensitivity monochromatic excitation energy dispersive X-ray fluorescence spectrometry

The coverage of the components required in the technical conditions of copper concentrate ranges from main, macro, micro to trace. Therefore, it is difficult to determine these components in copper concentrate simultaneously using one instrument technology. The monochromatic excitation energy dispersive X-ray fluorescence spectrometer uses hyperboloid bent crystal confocal technique for the monochromatization of X-ray continuous spectrum, thus reducing the interference of continuum background, decreasing the limit of detection, and enhancing the sensitivity. The detection range of the components can cover the main to trace. In experiments, a method for the analysis of 16 components including main components (Cu, S, Fe, SiO₂), macro-components (CaO, MgO, Al₂O₃), micro and trace components (Zn, Ni, Cr, Pb, Sb, Cl, Ag, As, Bi) in copper concentrate was established based on high sensitivity monochromatic excitation energy dispersive X-ray fluorescence spectrometer (HS-EDXRF) and fast fundamental parameter (FP) method. The copper concentrate samples were determined according to the experimental method. The found results were compared with those obtained by the standard methods or classical analysis methods, and there was no significant difference (All t_0.05,82 values were less than 1.98). In addition, the relative standard deviations (RSD, n=7) of determination results for main components (Cu, S, Fe, SiO₂), macro-components (CaO, MgO, Al₂O₃), micro components (Zn, Ni, Cr, Pb, Sb, Cl), and trace components (Ag, As, Bi) were not more than 0.70%, 1.6%, 3.3% and 10%, respectively. The proposed method could meet the detection requirements of 16 elements in copper concentrate in copper smelting process.