经验系数-X射线荧光光谱法测定镁质耐火材料中10种组分

摘要

为了适应各类镁质耐火材料的测定要求,实验以样品与混合熔剂(Li2B4O7-LiBO2-LiBr)稀释比为1∶10、1 050 ℃熔融20 min制备玻璃片,应用X射线荧光光谱法(XRF)测定镁质耐火材料中MgO、CaO、SiO2、Al2O3、Fe2O3、MnO、P2O5、TiO2、Cr2O3、K2O等10种组分.以光谱纯物质、标准样品、纯物质与标准溶液合成样品、化学定值样品联合制作校准曲线.通过经验系数法判据对基体项的计算值间的比较以选择校正项参与各组分的基体效应校正,各组分校准曲线拟合准确,有效克服了镁质耐火材料中各组分测定时基体效应的影响.对样品进行精密度试验考察,相对标准偏差(RSD,n=7)在0.053%~3.1%之间.对标准样品及未知样品进行准确度考察,测定值与认定值或湿法值一致.%In order to meet the testing requirements of various magnesia refractory materials, a fusion sample preparation technique was developed with mixed flux (Li2B4O7-LiBO2-LiBr) under the following conditions: dilution ratio of 1∶10, temperature of 1 050 ℃ and fusion time of 20 min.The contents of ten components in magnesia refractory materials (including MgO, CaO, SiO2, Al2O3, Fe2O3, MnO, P2O5, TiO2, Cr2O3 and K2O) were determined by X-ray fluorescence spectrometry (XRF).The calibration curves were prepared using spectral pure reagents, certified reference materials, synthetic samples by pure reagents and standard solution, and chemically certified materials.The correction was selected to correct the inter-element effects according to the comparison of value of the criteria of empirical calibration method.The calibration curves of each component were fitted well, and the matrix effect in magnesia refractory materials was effectively corrected.The precision tests were performed with magnesia refractory materials.The relative standard deviations (RSD, n=7) were between 0.053% and 3.1%.The accuracy tests were also conducted with standard and unknown samples.The found results were consistent with the certified values and those obtained by wet method.