高倍稀释熔融制样-X射线荧光光谱法测定铅锌矿中主次组分

将110 ℃烘干的样品在700 ℃高温焙烧后, 采用混合熔剂(m_LiB2O4∶ m_LiBO2∶ m_LiF=4.5∶1∶0.4)和样品以30∶1的质量比进行稀释, 加入2 g 硝酸铵为氧化剂, 加入溴化锂溶液为脱模剂熔融制样, 使用康普顿散射线内标法结合经验系数法对基体效应进行校正, 建立了测定铅锌矿石中铅、锌、铜、二氧化硅、三氧化二铝、全铁、二氧化钛、氧化锰、氧化钙、氧化镁、氧化钾、氧化钠、锑、铋、银15种组分的X射线荧光光谱分析方法。对国家铅锌标准物质GBW07163进行分析, 各组分的相对标准偏差(RSD)为0.29%～7.1%;分析不参加回归的国家铅锌矿石标准物质GBW07165、GBW07173, 结果与认定值相符, 完全满足日常生产的需要。

Determination of major and minor components in lead-zinc ores by X-ray fluorescence spectrometry with high dilution fusion sample preparation

After sample was dried at 110 ℃, calcined at 700 ℃, mixed flux (m_LiB2O4∶ m_LiBO2∶ m_LiF = 4.5∶1∶0.4) and sample were diluted to 30∶1, before 2 g of NH₄NO₃ was added as the oxidant, and lithium bromide solution was added as the release agent. The resulting mixture was fused for sample preparation. The matrix effect was corrected with Compton scattering internal standard method together with the experiential coefficient method, and thus the quantitative analytical method for the determination of 15 components including Pb, Zn, Cu, SiO₂, Al₂O₃, TFe₂O₃, TiO₂, MnO, CaO, MgO, K₂O, Na₂O, Sb, Bi and Ag in lead-zinc ore by X-ray fluorescence spectrometry was established. The method was applied to the analysis of the national lead-zinc certified reference material GBW07163, with the relative standard deviation for each component of 0.29%-7.1 %. And the analysis of national lead-zinc ore certified reference materials GBW07165 and GBW07173 that did not participate in regression testing rendered results consistent with the certified values, so it could fully meet the require of daily production.