Study On The Novel Sample Pretreatment Methods In Ion Chromatography

In this work, the technology of sample pretreatment prior to ion chromatographic detection was investigated systematically. A novel method for the determination of organic compounds in solid samples had been developed using ionic liquid aqueous solution as extractant coupled with ion chromatography. A simplified column-switching technique for the determination of trace inorganic anions in the presence of high concentration of sample matrix is established as well, Compared to traditional column-switching method, only one pump was used in this system, so it was called single-pump-column-switching. The major content was composed of four chapters.Chapter one comprised a brief intriduction of sample pretreatment prior to ion chromatographic detection. It mainly focuses on analysis and determining method of ionic liquid aqueous solution as extractant and column-switching method to eliminate high concentration of sample matrix.In chapter two, ionic liquid aqueous solution was used for the extraction of organic compounds in solid samples. Extraction parameters including concentration of ionic liquid, extraction time, and the volume ratio of extraction solvent to aqueous phase were optimized. Chromatographic conditions were also examined.In chapter three, a simplified ion-exclusion and ion-exchange single-pump column-switching method was set up. Ion chromatography (IC) has been proposed for the determination of three common inorganic anions (chloride, nitrate and sulfate) in weak acids using this system. Parameters such as switching time and chromatographic conditions were optimized.In chapter four, make full use of IC suppressor. Change the salts into acids before inject into ion chromatography. Single-pump column-switching method has been successfully applied to determination of common ionorganic anions in weak acid salts.