用于X射线荧光光谱法测定镁质耐火材料的变质镁砂标样认定值的修正与再利用

镁砂标样易吸潮变质,为了探讨变质镁砂标样继续使用的可能性,对9种烧失量已经发生变化的镁砂标准样品进行了条件试验,对变质镁砂标样的推荐值进行了校正。将样品进行高温灼烧处理,再通过定性半定量程序确定其未知元素的种类和含量,采用熔融制样法,建立了基于变质镁砂标样的高硅质镁基耐火材料中MgO、SiO₂、CaO、Al₂O₃、Fe₂O₃、K₂O、MnO、P₂O₅的X射线荧光光谱(XRF)分析方法。实验方法用于测定1个变质镁砂标样镁砂425中MgO、SiO₂、CaO、Al₂O₃、Fe₂O₃、MnO、P₂O₅,其中K₂O测定结果的相对标准偏差(RSD,n=11)为11%,其他组分的RSD(n=11)均在3%以下;按照实验方法测定2个变质镁砂标样和2个人工合成样品中MgO、SiO₂、CaO、Al₂O₃、Fe₂O₃、MnO、P₂O₅,测定值与认定值/理论值相符,允许差满足国家标准分析方法的分析要求,使变质镁砂标准样品能够回收再利用。

Correction of certified values and reuse of metamorphic magnesia standard sample for the determination of magnesium-based refractories by X-ray fluorescence spectrometry

The standard sample of magnesia is easily metamorphic due to moisture absorption. In order to discuss the possibility of continuing to use the metamorphic standard sample of magnesia, nine metamorphic standard sample of magnesia (the loss on ignition had been changed) were used for condition experiments. The recommended values of metamorphic standard sample of magnesia were corrected. The sample was firstly treated by high temperature burning. Then the type and content of unknown elements were obtained by qualitative and semi-quantitative procedures. Finally, the analysis method of MgO, SiO₂, CaO, Al₂O₃, Fe₂O₃, K₂O, MnO and P₂O₅ in high-silicon magnesium-based refractories by X-ray fluorescence spectrometry (XRF) based on metamorphic standard sample of magnesia was established after fusion sample preparation. The proposed method was applied for the determination of MgO, SiO₂, CaO, Al₂O₃, Fe₂O₃, K₂O, MnO and P₂O₅ in one metamorphic standard sample of magnesia 425. The relative standard deviation (RSD, n=11) of determination results of K₂O was 11%, and the RSDs (n=11) of other components were all less than 3%. The contents of MgO, SiO₂, CaO, Al₂O₃, Fe₂O₃, MnO and P₂O₅ in two metamorphic standard sample of magnesia and two synthetic samples were determined according to the experimental method. The found results were consistent with the certified values or theoretical values. The allowable error could meet the analytical requirements of national standard analysis method. The metamorphic standard samples of magnesia could be recycled.