Binary Stationary Phase Of Mix IL For Gas Chromatography

Ionic liquid capillary gas chromatography columns have been the focus of gas chromatography column development in recent years and are also one of the emerging commercial column types.Most of the stationary phases of existing ionic liquid capillary gas chromatography columns are single-component ionic liquids.The nature of the ionic liquid itself has a major influence on its separation ability,and the separation performance is quite different.Therefore,by mixing a variety of ionic liquids with different functional groups,by adjusting the type of functional groups,the selectivity of the stationary phase is adjusted within a certain range,the separation ability of the stationary phase is improved,and a partially controlled capillary gas chromatography column is developed.,Is one of the development directions of capillary gas chromatography column stationary phase field.The research content mainly includes the following parts:1.Synthesis of ionic liquids used in stationary phases of commercial ionic liquid chromatography columns and ionic liquids of similar structure.By analogy with its synthesis method,a double cationic ionic liquid containing a benzene ring functional group in the middle connecting bridge and 1-methylimidazole on both sides is synthesized.The thermal stability of the three ionic liquids was measured separately.The 5%thermal weight loss temperature of the three ionic liquids reached 380 ~oC or more.2.The chromatographic column of pure ionic liquid was prepared by static coating method.The performance of synthetic ionic liquid and commercial ionic liquid stationary phase was compared.The performance of the three chromatographic columns prepared under the common carrier gas flow rate is guaranteed to be in the range of 2000-4000 plates/meter,And the polarities of the Mc Reynolds constant are in the range of 3700-4100,belongs to ultra-high polarity chromatography column.The synthesized ionic liquids have similar separation performance as commercial chromatographic columns and can meet the standards of commercial chromatographic columns.Two kinds of dicationic ionic liquids with a middle connecting bridge as heptane and benzene ring functional groups were selected,and three different ratios of mixed ionic liquid stationary phase capillary gas chromatographic columns were prepared by static coating method.The prepared chromatographic column can guarantee a column efficiency of 2000-4000trays/meter under the commonly used carrier gas flow rate,and its Mie's constant polarity is in the range of the polarity value of 4000-5000,and the highest polarity value reaches 4793.the Abraham solvation parameters of capillary chromatography columns with different ratios of stationary phases were evaluated,and the separation ability of ionic liquid capillary chromatography columns with different ratios to Grob reagent was compared and analyzed.It is found that the hydrogen bonding acidity of the mixed ionic liquid is inversely proportional to the mixing ratio of the ionic liquid with a benzene ring in the middle,and part of the acting force also shows a correlation with the mixing ratio,which can achieve a certain degree of separation ability adjustment.