粉末压片-能量色散X射线荧光光谱法测定钛精矿中6种组分

采用化学湿法分析时,钛精矿中钛极易水解并形成难溶的偏钛酸析出,给分析带来极大的阻碍,同时分析周期长,方法繁杂。实验采用粉末压片法制样,能量色散X射线荧光光谱法(EDXRF)同时测定钛精矿中硫、磷、氧化锰、五氧化二钒、氧化钙、氧化镁。选取钛精矿粒度为40μm,以硼酸为粘连剂,压片压力为25MPa,保压时间为60s压制光滑、无裂痕的样片。选用4~5个钛精矿标准样品制作校准曲线,同时采用基本参数法进行基体效应的校正,各待测组分校准曲线的线性相关系数均不小于0.997,各组分检出限为0.00049%~0.076%。按照实验方法测定钛精矿样品中硫、磷、氧化锰、五氧化二钒、氧化钙、氧化镁,测定结果的相对标准偏差(RSD,n=8)为0.71%~7.9%;方法用于测定两个钛精矿标准样品中硫、磷、氧化锰、五氧化二钒、氧化钙、氧化镁,测定值与认定值结果一致。

Determination of six components in titanium concentrate byenergy dispersive X-ray fluorescence spectrometrywith pressed powder pellet

In chemical wet analysis, titanium in titanium concentrate was easily hydrolyzed to form insoluble metatitanic acid precipitation, which brought greatly hinderance to the analysis. Meanwhile, the analysis period was long and the process was complex. The sample was prepared by pressed powder pellet. The contents of sulfur, phosphorus, manganese oxide, vanadium pentoxide, calcium oxide and magnesium oxide in titanium concentrate were simultaneously determined by energy dispersive X-ray fluorescence spectrometry. The particle size of titanium concentrate sample in experiments was 40μm. The boric acid was selected as the adhesive. The pressure for pressed powder pellet was 25MPa and the holding time was 60 seconds. The prepared sample was smooth without cracking. 4-5 certified reference materials were used to prepare the calibration curves. The matrix effect was corrected with the fundamental parameter (FP) method. The linear correlation coefficients of calibration curves for all components were not less than 0.997. The detection limits were between 0.00049% and 0.076%. The contents of sulfur, phosphorus, manganese oxide, vanadium pentoxide, calcium oxide and magnesium oxide in titanium concentrate sample were determined according to the experimental method. The relative standard deviations (RSDs, n=8) of the results were between 0.71% and 7.9%. The proposed method was applied for the determination of sulfur, phosphorus, manganese oxide, vanadium pentoxide, calcium oxide and magnesium oxide in two titanium concentrate certified reference materials, and the results were consistent with the certified values.