X射线荧光光谱法测定锆矿中10种主次成分

采用四硼酸锂和偏硼酸锂混合熔剂熔融制样,利用X射线荧光光谱仪(XRF)测定锆矿中的ZrO₂、HfO₂、MgO、Al₂O₃、SiO₂、P₂O₅、CaO、TiO₂、Fe₂O₃、BaO等10种主次成分含量。利用锆矿标准物质及锆矿标准物质与基准试剂SiO₂、Al₂O₃、TiO₂、Fe₂O₃、CaCO₃、KH₂PO₄、MgO、BaO、HfO₂按一定比例混合配制的系列校准样品绘制校准曲线,满足各成分的含量梯度。选择0.450 0 g样品加入9.000 g混合熔剂(m_四硼酸锂∶m_偏硼酸锂=12∶22)、熔样时间为15 min、熔融温度为1 050 ℃、无需加脱模剂进行熔融,熔样效果好。选择ZrL_α线避免了ZrK_α线以及ZrK_β线穿透样片的问题;采用变异α系数校正基体效应。对锆矿石标准样品及自制校准样品进行分析,各成分的测定值与认定值或参考值相吻合;精密度考察结果表明各成分测定结果的相对标准偏差在0.29%～7.9%之间。

Determination of ten major and minor components in zirconium ore by X-ray fluorescence spectrometry

Ten major and minor components in zirconium ores such as ZrO₂, HfO₂, MgO, Al₂O₃, SiO₂, P₂O₅, CaO, TiO₂, Fe₂O₃, BaO were determined by X-ray fluorescence spectrometry (XRF) with fusion sample preparation (lithium tetraborate-lithium metaborate as flux). The calibration curve was established with zirconium ore reference materials and calibration sample series prepared by mixing zirconium ore reference materials with SiO₂, Al₂O₃, TiO₂, Fe₂O₃, CaCO₃, KH₂PO₄, MgO, BaO, HfO₂ standard reagent at certain proportion, which could satisfy the content gradient of each component. When 0.450 0 g of sample was fused with 9.000 g of mixed flux (m_Li2B4O7∶m_LiBO2=12∶22) for 15 min at 1 050 ℃ without adding release reagent, the sample fusion effect was satisfactory. ZrL_α was selected instead of ZrK_α and ZrK_β to avoid sample penetrating problem. Variable α coefficient was adopted to correct matrix effect. The zirconium ore reference materials and self-made calibration sample were analyzed. The results were consistent with the certified values or reference values. The precision test showed that the relative standard deviation (RSD) of each component was 0.29%-7.9%.