熔融制样-X射线荧光光谱法测定钛铁矿中主次组分

使用Li₂B₄O₇和LiBO₂混合熔剂(质量比为67∶33),NH₄NO₃作氧化剂,饱和LiBr溶液作脱模剂,在电加热熔样机上制备玻璃熔片,建立了波长色散X射线荧光光谱法(WD-XRF)测定钛铁矿物中TiO₂、TFe、SiO₂、A1₂O₃、V₂O₅、MgO、CaO、S、P、Na₂O的分析方法。实验表明,在熔样比例(质量比)为15∶1、熔样温度为1 100 ℃、熔样时间为15 min时熔样效果最佳。在最佳实验条件下,在自制钛铁矿标准样品的含量范围内,各组分的含量与其荧光强度呈线性关系,相关系数在0.995 6~0.999 7之间。采用基本参数法对基体效应进行校正后,平行测定样品10次,所得结果的相对标准偏差除P为9.8%外,其它各组分均不大于1.3%。采用实验方法对钛铁矿样品中各组分进行测定,所得结果和湿法测得值一致。

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

The glass fusion piece of sample was prepared on electrical heating fusion machine with Li₂B₄O₇-LiBO₂ (mass ratio of 67∶33) as mixed flux, NH₄NO₃ as oxidant and saturated LiBr solution as releasing agent. Consequently, a method for determination of TiO₂, TFe, SiO₂, A1₂O₃, V₂O₅, MgO, CaO, S, P and Na₂O in ilmenite was established by wavelength dispersion X-ray fluorescence spectrometry. The results showed that the optimal sample fusion conditions were as follows: sample-flux ratio (mass ratio) of 15∶1, sample fusion temperature of 1 100 ℃ and fusion time of 15 min. Under the optical experiments conditions, component content was linear to the fluorescence intensity within the content range of self-made lmenite reference samples, and correlation coefficients were between 0.995 6 and 0.999 7. After matrix effect was corrected by fundamental parameter method, the relative standard deviations (RSD, n=10) were not more than 1.3 % except for P (9.8 %). The proposed method was applied to the determination of components in ilmenite actual samples, and the results were consistent with those obtained by wet method.