地下水及矿泉水中二氧化硅的传统分析方法过程皆比较繁冗,采用电感耦合等离子体-原子发射光谱法(ICP-AES)测定地下水及矿泉水中的二氧化硅.在选定了较灵敏的硅分析线后,探讨了ICP光谱仪工作条件对分析结果的影响,同时研究并消除共存离子对SiO2测定结果的影响.通过条件实验,选择仪器的发射功率为1 350 W,观测高度为12 mm,雾化器压力为0.20 MPa,泵速为75 r·min-1.在光谱仪最佳分析条件下,利用该方法测定地下水及矿泉水中二氧化硅的含量,其检出限为0.017 mg·L-1,加标回收率在94.10%～103.8%之间,相对标准偏差(RSD)≤3.06%,同时与硅钼黄分光光度法进行对比实验,结果基本吻合,相对偏差≤3.00%,本方法简便快捷,精密度和准确度较高,可以用于科研及日常生产中。

The concentration of silica in groundwater and mineral water was determined by inductively coupled plasma-atomic emission spectrometry(ICP-AES).After a more sensitive analytical line of silicon was chosen,the effects of operating conditions of the ICP spectrometer on the analysis results were investigated,at the same time,the impact of coexisting ions on determination results of SiO2 was also considered and eliminated.The transmit power of 1 350 W,observation height of 12 mm,the nebulizer pressure of 0.20 MPa and the pump speed of analysis of 75 r·min-1 were selected by experimental conditions.Under the optimum analytical conditions of spectrometer,the method was used for the determination of SiO2 in groundwater and mineral water with the detection limit of 0.017 mg·L-1,recoveries between 94.10% and 103.8%,and relative standard deviation(RSD)≤3.06%.Compared with the results of silicon molybdenum yellow spectrophotometry,the results were basically consistent with the relative deviation ≤3.00%.In conclusion,the method is simple and efficient with high precision and accuracy,and can be used for research and routine production.