电感耦合等离子体原子发射光谱法测定蛭石中4种氧化物

采用碳酸钠-硼酸混合熔剂在950 ℃熔融样品6～8 min、然后使用盐酸(1+4)浸取后,选择Si 288.158 nm、Ca 315.887 nm、Fe 238.204 nm、Al 308.215 nm为分析线,使用电感耦合等离子体原子发射光谱法(ICP-AES)同时测定蛭石中SiO₂、CaO、Fe₂O₃及Al₂O₃。各组分的质量分数在一定范围内与其发射强度呈线性,校准曲线的线性相关系数r均不小于0.999 5。实验方法用于测定玄武岩标准物质GBW07105和实际蛭石样品SiO₂、CaO、Fe₂O₃及Al₂O₃,结果的相对标准偏差(RSD,n=6)为0.61%～1.8%;各组分的测定结果与认定值或者其他化学方法的测定值相吻合。

Determination of four oxides in vermiculite by inductively coupled plasma atomic emission spectrometry

The sample was fused with sodium carbonate-boric acid mixed flux at 950 ℃ for 6-8 min followed by leaching with hydrochloric acid (1+4). The content of SiO₂, CaO, Fe₂O₃ and Al₂O₃ in vermiculite was simultaneously determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) using Si 288.158 nm, Ca 315.887 nm, Fe 238.204 nm and Al 308.215 nm as analytical lines. The mass fraction of each component in certain range showed linearity to emission intensity. The linear correlation coefficients of calibration curves were higher than 0.999 5. The proposed method was applied to the determination of SiO₂, CaO, Fe₂O₃ and Al₂O₃ in certified reference materials and actual samples of basalt. The relative standard deviations (RSD, n=6) were between 0.61% and 1.8%. The found results of each component were consistent with the certified values or those obtained by other chemical methods.