摘要
文章采用一种新的熔融钒钛磁铁矿样方法,利用X射线荧光光谱法(X-ray fluorescence,XRF)测定钒钛磁铁矿中的铁、钛、钒组分。以Li_2B_2O_7+LiBO_2+LiF(配料比45∶10∶5)为主熔剂,Li_2CO_3为助熔剂,试样稀释比为1∶25,熔融温度为1 150℃,熔融时间为10min,发现熔融后样品消除了粒度效应和矿物效应,使得荧光强度基本接近最高强度,实现了基体效应及谱线重叠干扰的校正。通过加入钴内标,提高铁的测定精度;选用LiF220晶体测定钒,大大降低钛的干扰。该方法用于钒钛磁铁矿国家一级标准物质的测定,其结果与标准值吻合,与传统经典方法相比,矿样处理更为简单,消除了系统偏差。实验表明,铁、钛、钒各组分的精密度(RSDn=12)为0.75%~3.03%。
A new method to quantify the amount of Fe,Ti and V in the vanadium titanium magnetite(V-Ti-Mag)by X-ray fluorescence(XRF)was applied.In this method,the V-Ti-Mag was melted by using reagents of Li_2B_2O_7+LiBO_2+LiF at a mass ratio of 45∶10∶5.The Li_2CO_3 was employed as co-assistant melting reagents to get easier transfer from the platinum crucible.The mass ratio of minerals samples and co-agents was set at 1∶25,the calcination temperature was 1 150℃,and the calcination time was 10 min.The XRF spectrometry was used to analyze the melted samples.The results show that the effects of the grain size and external minerals can be readily avoided,and the intensity of the fluorescence reaches the maximum.By using Co as the internal standard,the accuracy of Fe measurements is improved.Crystals of LiF220 were utilized to remove the disturbance of Ti when the content of V was determined.This strategy can achieve the facile adjustment of the matrix effects and better correction of spectral overlapping interferences.The results of the percentages of Fe,Ti and V in V-Ti-Mag obtained via this method were demonstrated to be consistent with the standard values of the known minerals.Compared with the traditional ones,this method simplifies the sample treatments without obvious systematic error.The precision(RSDn=12)of the measurements of Fe,Ti and V is evaluated to be within 0.75%-3.03%,which is the best results up to date.
引文
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