熔融制样-X射线荧光光谱法测定铝矿、铁矿、钙矿、镁矿和锰矿中主要组分

熔融制样-X射线荧光光谱法(XRF)被应用到很多种类矿物样品中的主次组分的测试,但地矿实验室需要测试的矿物种类较多,单一的矿物种类测试很难满足测试需求。实验采用熔融制样法,以多种矿物标样及其混合标样为基础,建立了一种可用于多种类型矿物主要组分的X射线荧光光谱分析方法。实验确定熔融条件为样品量0.400 0 g,助熔剂为7.000 0 g四硼酸锂,加入4滴150 g/L溴化锂溶液为脱模剂,0.500 0 g硝酸锂氧化剂和0.400 0 g氟化锂流化剂。结果表明样品基体效应对测试结果影响不大。精密度考察发现:铝矿中主成分Al₂O₃、铁矿中主成分Fe、钙矿中主成分CaO、镁矿中主成分MgO、锰矿中主成分Mn的相对标准偏差(RSD,n=6)分别为0.49%、0.37%、0.64%、0.38%、0.85%。正确度考察发现:5种矿物样品中SiO₂、Al₂O₃、Ca、MgO、Mn、Fe的测定值与其他方法测定值相吻合。方法采用一套标准样品可测试多种矿物样品中主要组分,适用于地矿实验室矿物样品分析。

Determination of major components in aluminum ore,iron ore,calcium ore,magnesium ore and manganese ore by X-ray fluorescence spectrometry with fusion sample preparation

X-ray fluorescence spectrometry (XRF) with fusion sample preparation has been applied for the determination of major and minor components in various ore samples. However, many types of minerals should be tested in geological laboratory, and the test for single ore can hardly meet the requirements. The fusion sample preparation method was adopted in experiments. A method for the analysis of major components in various ores by XRF was established based on the standard samples and mixed standard samples of different ores. The following fusion conditions were obtained in experiments: 0.400 0 g of sample was added into 7.000 0 g of lithium tetraborate as the flux; 4 drops of 150 g/L lithium bromide solution were used as release agent; 0.500 0 g of lithium nitrate was used as oxidizing agent and 0.400 0 g of lithium fluoride was used as fluidizing agent. The result showed that the influence of matrix effect on determination results was not significant. The presicion test was conducted,and the relative standard deviation (RSD, n=6) of major component,such as the Al₂O₃ in aluminum ore, the Fe in iron ore, the CaO in calcium ore,the MgO in magnesium ore, and the Mn in manganese ore was 0.49%, 0.37%, 0.64%, 0.38% and 0.85%, respectively.Trueness test showed that the found results of SiO₂, Al₂O₃, Ca, MgO, Mn and Fe in 5 mineral samples were consistent with those obtained by other methods. The proposed method used a set of standard samples for the analysis of major components in various ores sample, and it could be used for the testing in geological laboratory.