熔融制样-X射线荧光光谱法测定炮泥中氧化铁、氧化铝和氧化钙  

Determination of iron oxide,aluminum oxide and calcium oxide in taphole clay by X-ray fluorescence spectrometry with fusion sample preparation

作　　者：蒋政 罗旻延 杨正平 雷坚 黄义伟 钟楚阳 JIANG Zheng;LUO Minyan;YANG Zhengping;LEI Jian;HUANG Yiwei;ZHONG Chuyang(Liuzhou Steel Co.,Ltd.Quality Control Department,Liuzhou 545002,China;Liuzhou Steel Co.,Ltd.Mechanical Engineering Department,Liuzhou 545002,China)

机构地区：[1]柳州钢铁股份有限公司质量管理部,广西柳州545002 [2]柳州钢铁股份有限公司机动工程部,广西柳州545002

出　　处：《冶金分析》2023年第11期30-38,共9页Metallurgical Analysis

摘　　要：炮泥是一种不定型功能性耐火材料。测定其中的氧化铁、氧化铝和氧化钙有助于把控炮泥的产品质量。炮泥的杂质组分较多,其中氮化硅和碳化硅的存在导致了熔片制备困难,限制了X射线荧光光谱法(XRF)在此类物料中的应用。试验采用先分解杂质组分后熔融制片的方法,以氢氧化锂分解样品中氮化硅,以硝酸钠和过氧化钡分解碳化硅,再以四硼酸锂-偏硼酸锂混合熔剂作为反应基底隔绝反应物并中和过量的强碱,最后熔融制备玻璃熔片,建立了熔融制样-X射线荧光光谱法测定炮泥中氧化铁、氧化铝和氧化钙的分析方法。用氧氮分析仪对热碱反应产物进行分析,确定了炮泥与氢氧化锂最佳比例。通过空白实验、对比实验并以扫描电子显微镜(SEM)、X射线衍射(XRD)表征和图像分析(Mapping)对实验样品进行表征,结果表明:高温熔融后四硼酸锂能将氢氧化锂完全中和,产物以偏硼酸锂为主有利于X射线荧光光谱分析。氢氧化锂能有效分解氮化硅,避免了由氮化硅微粒造成的组分聚集现象,使熔片表面光洁、平整。按照实验方法测定炮泥生产样品中氧化铁、氧化铝和氧化钙,结果的相对标准偏差(RSD,n=10)为0.28%~4.6%;并与氟盐置换EDTA滴定法和电感耦合等离子体原子发射光谱法的差值均在GB/T 6900—2016允差范围内。Taphole clay is a kind of amorphous functional refractory material.The determination of Fe2O3,Al2O3 and CaO contents is helpful to control the product quality.There are many impurity components in the taphole clay,and the presence of silicon nitride and silicon carbide leads to the difficulty of fusion sample preparation,which limits the application of X-ray fluorescence spectrometry in the analysis of taphole clay materials.In this study,the impurity components were firstly decomposed followed by fusion sample preparation.Lithium hydroxide was used to decompose silicon nitride,while sodium nitrate and barium peroxide were used to decompose silicon carbide.Then lithium tetraborate-lithium metaborate mixed flux was used as the reaction base to isolate reactants and neutralize the excessive strong bases.Finally,the sample was fused to prepare the pieces.A method for the analysis of iron oxide,aluminum oxide and calcium oxide in taphole clay by X-ray fluorescence spectrometry with fusion sample preparation was established.The product of hot alkali reaction was analyzed by oxygen-nitrogen analyzer,and the optimum ratio of taphole clay to lithium hydroxide was determined.The test samples were characterized by blank experiments,contrast experiment,scanning electron microscopy(SEM),X-ray diffraction(XRD)and image Mapping.The results showed that lithium tetraborate could neutralize lithium hydroxide completely after melting at high temperature,and the main product of lithium metaborate was conducive to the analysis by X-ray fluorescence spectrometry.Lithium hydroxide could effectively decompose silicon nitride,avoiding the phenomenon of component aggregation caused by silicon nitride particles.So that the surface of the melt piece was clean and smooth.The contents of iron oxide,aluminum oxide and calcium oxide in taphole clay product samples were determined according to the experimental method,and the relative standard deviations(RSD,n=10)of determination results were between 0.28%and 4.6%.The differences between fluorid

关 键 词：炮泥 氧化铁 氧化铝 氧化钙 氮化硅 碳化硅 X射线荧光光谱法(XRF) 耐火材料 预氧化 熔融制样 氢氧化锂 

分 类 号：O657.34[理学—分析化学] TF03[理学—化学]