采用混合氧化剂氧化熔融制样,建立了X射线荧光光谱分析铝碳质耐火材料中的Al2O3、SiO2、CaO、MgO、Fe2 O3、Cr2O3、TiO2等组分的方法,讨论了混合氧化剂配比、氧化时间、熔剂及稀释比、脱模剂、灼烧减量等因素对制样及分析结果的影响.通过正交试验确定预氧化条件为:Na2O2加入量与试样量比为4∶1、NaNO3加入量与试样量比为2∶1,预氧化时间为90 min;使用四硼酸锂偏硼酸锂混合熔剂(质量比67∶33)做熔剂,稀释比30∶1,碘化铵做脱模剂,熔制出的熔片效果最理想；对于存在较大灼烧减量的样品,可先灼烧后测定,并通过灼烧减量值和测定值计算得出较为理想的结果.经验证,该法分析精密度较好,各组分相对标准偏差(n=9)在0.29％～2.9％之间,分析结果与化学值能够很好的吻合.%The sample was prepared by fusion using mixed oxidizing agents. The determination method of A12O3, SiO2, CaO, MgO, Fe2O3, Cr2O3 and TiO2 in alumina carbon refractory materials by X-ray fluorescence spectrometry was established. The effect of mixed oxidizing agent ratio, oxidization time, flux and dilution ratio, release agent and loss on ignition on the sample preparation and analytical results were discussed. The pre-oxidization conditions were determined by orthogonal experiments: the ratio of Na2 O2 and sample was 4 : 1, the ratio of NaNO3 and sample was 2 : 1, and the pre-oxidization time was 90 min; when lithium tet-raborate-lithium metaborate mixed flux (mass ratio of 67 : 33) was used with dilution ratio of 30 : 1 and ammonium iodide was used as the release agent, the sample reparation results were best; for the samples with large loss on ignition, they could be determined after ignition, and the ideal results could be obtained based on the loss on ignition and the measured results. It was verified that, the analytical precision of this method was good. The relative standard deviations (RSDs, n=9) of components were 0. 29%-2. 92%. The analytical results were in good agreement with those obtained by chemical method.
展开▼
