液相色谱-离子色谱联用法同时测定工业废水中的苯胺和5种无机金属离子

Simultaneous determination of aniline and five inorganic metal ions in waste water by liquid chromatography coupled with ion chromatography

目的建立液相色谱-离子色谱联用法同时测定工业废水中苯胺和5种无机金属离子(锂、钠、钾、钙、镁)。方法废水样品经0.22μm过滤头过滤除去固体杂质后,注入色谱系统,经在线固相萃取分离以及阀的切换,将无机金属离子切换到离子色谱系统进行分析,将苯胺切换到液相色谱系统进行分析;以保留时间定性,外标法定量。本方法包括系统平衡、样品装载至定量环、富集无机组分、分析无机组分和富集有机组分、分析有机组分和在线固相萃取柱的净化5个步骤。结果优化了阀切换的时间以及色谱测定条件。在最佳条件下,方法相关系数均>0.999,检出限在1.6 mg/L^8.0 mg/L,相对标准偏差<3.0%,回收率为94.0%~106.0%。结论本法能够实现工业废水中的苯胺和锂、钠、钾、钙和镁的同时测定,弥补了传统方法的不足,操作简便、快速,可应用于实际样品的分析。

Objective To establish a liquid chromatography coupled with ion chromatography method for the simultaneous determination of aniline and five inorganic metal ions（ Li＋,Na＋,K＋,Mg2 ＋and Ca2 ＋） in waste water. Methods Waste water sample was filtered through a 0. 22 μm filter to remove solid impurities,and then injected into the chromatographic system. The sample was separated by an on- line SPE column,and inorganic metal ions and aniline were switched to the LC system for analysis. Retention time and external standard method were respectively used for qualitativeness and quantification. The method was divided into five steps： system balance,sample loading to the quantitative loop,enrichment of the inorganic components,analysis of inorganic components and enrichment of organic components,analysis of the organic components and on- line solid phase extraction column purification. Results The time of valve switching and the condition of chromatographic determination were optimized. Under the optimized conditions,the correlative coefficients（ r） of the method was greater than 0. 999. Detection limits were within 1. 6 mg / L- 8. 0 mg / L,with relative standard deviations（ RSDs） less than 3. 0%. The recovery rates were within94. 0%- 106. 0%. Conclusion This method could be applied for the simultaneous determination of aniline,Li＋,Na＋,K＋,Mg2 ＋and Ca2 ＋in waste water,which made up for the deficiency of the traditional method. It is simple and rapid,and can be applied to the analysis of actual samples.