压片制样-X射线荧光光谱法测定不锈钢渣中10种组分

由于不锈钢标渣在市场上很难购买,且熔融制样-X射线荧光光谱(XRF)无法满足炉前不锈钢渣样的快速分析要求,实验利用转炉渣、高炉渣、平炉渣等标准样品和文献方法定值的不锈钢渣生产样品,建立熔融制样-X射线荧光光谱的校准曲线,并用于不锈钢渣样的定值分析,将此定值分析结果用于压片制样-X射线荧光光谱校准曲线的绘制,从而实现不锈钢渣中CaO、SiO₂、Al₂O₃、MnO、MgO、TFe、P₂O₅、TiO₂、Cr₂O₃和NiO的炉前快速分析。对熔融制样的条件及方法的精密度和准确度均进行了考察,保证了绘制校准曲线用不锈钢渣测定结果的准确性。通过试验确定压片制样-X射线荧光光谱的分析条件为:研磨时间50 s;40 g试样中添加5粒粘合剂;100 kN压力,保压时间15 s进行压片。各组分校准曲线的相关系数均大于0.999。对同一不锈钢渣进行压片制样-XRF的精密度考察,各组分测定结果的相对标准偏差为0.43%～4.6%;准确度验证结果表明,压片制样的测定结果同熔融制样的测定结果一致,但压片制样XRF满足炉前不锈钢渣分析量大、分析速度快的要求。

Determination of ten components in stainless steel slag by X-ray fluorescence spectrometry with pressed powder pellet

The standard sample of stainless steel slag was hardly purchased in market. The determination of stainless steel slag sample by X-ray fluorescence spectrometry (XRF) with fusion sample preparation could not meet the requirements of rapid ladle analysis. Consequently, the certified reference materials of converter slag, blast furnace slag and open hearth slag as well as the production sample of stainless steel slag (which was certified using the reference method) were used to establish the calibration curve for XRF with fusion sample preparation, which was applied to the constant value analysis of stainless steel slag samples. The found results were used in the preparation of calibration curves for XRF determination with pressed powder pellet, realizing the rapid ladle analysis of CaO, SiO₂, Al₂O₃, MnO, MgO, TFe, P₂O₅, TiO₂, Cr₂O₃ and NiO in stainless steel slag. The sample preparation conditions, the precision and accuracy of method were investigated to guarantee the determination accuracy of stainless steel slag for the preparation of calibration curves. The analysis conditions of XRF with pressed powder pellet were obtained by experiments: the grinding time was 50 s; five granules of binding agent were added into 40 g of sample; tabletting pressure was 100 kN and the holding time was 15 s. The correlation coefficient of calibration curve of each component was higher than 0.999. The determination precision of one stainless steel slag sample by XRF with pressed powder pellet was investigated. The relative standard deviations (RSD) of components were between 0.43% and 4.6%. The accuracy test results indicated that the results of proposed method were consistent with those obtained by fusion sample preparation. However, the XRF with pressed powder pellet could meet the requirements of large amount and rapid analysis of stainless steel slag in ladle analysis.