熔融制样-X射线荧光光谱法测定金红石中主次组分

评价金红石品位时,常需要知道金红石的主次组分含量。金红石样品中二氧化钛含量很高,属于难熔化合物,在采用熔融制样-X射线荧光光谱法测定时熔融片容易破碎和炸裂。实验在对稀释比和熔融温度进行优化的基础上,通过加入合适质量的玻璃成型剂二氧化硅,成功地制备了金红石熔融片,实现了X射线荧光光谱法(XRF)对金红石样品中Fe₂O₃、TiO₂、MnO、SiO₂、Al₂O₃、CaO、MgO、K₂O等主次组分的测定。采用钛铁矿标准样品、辉长岩标准物质及高纯试剂二氧化钛按一定比例研磨后混合均匀,配制成具有一定含量梯度的10个金红石合成样品绘制校准曲线,采用数学校正公式进行基体效应和谱线重叠校正,各主次组分校准曲线的相关系数均大于0.997 9。按照实验方法对由钛铁矿标准样品和高纯试剂二氧化钛按比例混合配制得到的金红石合成样品中的主次组分进行测定,计算测定结果的相对标准偏差(RSD)为0.22%～1.6%。采用实验方法测定由钛铁矿标准样品和高纯试剂二氧化钛按...

Determination of major and minor components in rutile by X-ray fluorescence spectrometry with fusion sample preparation

During the evaluation of rutile grade, the contents of major and minor components in rutile should be determined. The content of titanium dioxide in rutile sample was usually very high. Moreover, it belonged to refractory compound. Thus, the fused bead was easily broken and burst during the determination of rutile by X-ray fluorescence spectrometry (XRF) with fusion sample preparation. The dilution ratio and fusion temperature were optimized in experiments. The rutile fused bead was successfully prepared by adding suitable amount of glass molding agent SiO₂. Then, the determination of major and minor components (including Fe₂O₃, TiO₂, MnO, SiO₂, Al₂O₃, CaO, MgO, K₂O) in rutile by XRF was realized. The standard sample of ilmenite, the certified reference material of gabbro and titanium dioxide of high purity reagent were ground and uniformly mixed in a certain proportion to prepare 10 rutile synthetic samples with certain content gradients. Then the calibration curves were drown. The correction of matrix effect and spectral overlapping were carried out with mathematical correction formula. The correlation coefficients of calibration curves of major and minor components were all greater than 0.9979. The contents of major and minor components in rutile synthetic sample (which was prepared by proportional mixing of ilmenite standard sample and titanium dioxide of high purity reagent) were determined according to the experimental method. The relative standard deviations (RSD) of determination results were between 0.22% and 1.6%. Two rutile synthetic samples (which were prepared by proportional mixing of ilmenite standard sample and titanium dioxide of high purity reagent) were determined according to the experimental method. The determination results for the major and minor components were in good agreement with the theoretical values (calculated based on the certified values of standard samples).