熔融制样-X射线荧光光谱法测定微晶铸石中6种组分

利用工业废渣(高炉矿渣、钢渣、铜渣、铬渣、铁合金渣等)为主要原料生产微晶铸石效益巨大,而目前对微晶铸石中主要组分(SiO₂、Al₂O₃、CaO、MgO、TFe、TiO₂)的分析一般采用化学湿法,操作相对繁琐、流程长。实验采用Li₂B₄O₇-LiBO₂混合熔剂(m∶m=67∶33)按质量比为1∶12.5的比例进行熔融制样,无需采用氧化剂预氧化,加入0.15g NH₄I做脱模剂,消除了样品的矿物结构效应,降低了基体效应的影响,实现了熔融制样-X 射线荧光光谱法对微晶铸石中SiO₂、Al₂O₃、CaO、MgO、TFe和TiO₂含量的同时测定。实验选择与微晶铸石基体相似的国家级和行业级转炉渣、高炉渣、古冶熟料、矾土等标准物质人工合成校准样品绘制校准曲线,解决了微晶铸石标准物质缺失的问题,以数学回归法、基本参数法和理论影响系数法消除基体效应和谱线干扰,校准曲线的相关系数均大于0.999。对同一个微晶铸石样品进行精密度考察,6种组分测定结果的相对标准偏差(RSD,n=10)均小于5.0%;正确度验证结果表明,实验方法的测定值与其他方法的测定值吻合较好。

Determination of six components in microcrystalline cast stone by X-ray fluorescence spectrometry with fusion sample preparation

The production of microcrystalline cast stone from industrial residues (blast furnace slag, steel slag, copper slag, chromium slag, ferroalloy slag, etc) as main raw materials has great benefits. At present, the major components in microcrystalline cast stone (SiO₂, Al₂O₃, CaO, MgO, TFe and TiO₂) are usually analyzed by chemical wet method, which has some disadvantages such as relatively complicated operation and long analysis procedures. The sample was prepared by fusion method using Li₂B₄O₇-LiBO₂ mixed flux (m∶m=67∶33). The mass ratio between the sample and flux was 1∶12.5. The pre-oxidation by oxidant was not required. 0.15g of NH₄I was added as the release agent. The mineral structure effect of sample was eliminated and the influence of matrix effect was reduced. Thus the simultaneous determination of SiO₂, Al₂O₃, CaO, MgO, TFe and TiO₂ contents in microcrystalline cast iron by X-ray fluorescence spectrometry (XRF) with fusion sample preparation was realized. The calibration sample was artificially synthesized using the national-grade and industry-grade certified reference materials of converter slag, blast furnace slag, Guye chamotte and bauxite, which had similar matrix to microcrystalline cast stone, to prepare the calibration curve. The problem that there was no standard material of microcrystalline cast stone was solved. The matrix effect and spectral interference were eliminated by the mathematical regression method, the fundamental parameter method and the theoretical influence coefficient method. The correlation coefficients of calibration curves were all higher than 0.999. One microcrystalline cast stone sample was determined for the precision test. The relative standard deviation (RSD, n=10) of determination results of six components were all less than 5.0%. The correctness verification results indicated that the determination results of proposed method were in good agreement with those obtained by other methods.