Study On The Large Scale Synthesis Of Alkylimidazolium Based Ionic Liquids

The main job of green chemistry is to find some effective catalysts and additives, especially a kind of green medium with no pollution and volatility, which could be used as the succedaneum of organic solvents in traditional chemical reactions. Ionic liquids(ILs), a special class of organic salts, have attracted considerable attentions in academic and industrial field due to their greenness features, such as low melting point, wide range of liquid state, negligible vapor pressure, high ionic conductivity and unique dissolubility.At the present time, there are three kinds of Ionic liquids based on alkylimidazolium have been studied extensively: 1-butyl-3-methylimidazolium chloride(BMImCl), 1-butyl-2,3-dimethylimidazolium chloride(BMMImCl), and 1-butyl-3-methylimidazolium tetrafluoroborate(BMImBF4), which are promising in industrial application. The main work in this dissertation focus on the following content: The studies on synthesis pathway, the synthesis exploitation of large scale quantity, purity analysis and scheme of quality control. The key points of the paper including:(1) The methods of the synthesis about the three Ionic liquids were researched and compared, the optimum pathway and conditions to synthesize the ionic liquids have been screened. The factors as synthesis pathway, solvent species, and reaction condition were confirmed finally.(2) The works of kilogram, 10-kilogram model methods for synthesizing the three ionic liquids have been developed based on the optimum scheme. Exploration of the transfer of heat and mass during the scale process, researching the condition of the crystal producing, determination of the controlling conditions and postprocessing methods of the medium scale synthesis for the three Ionic liquids have been finished. After that, ton-model synthesis technology of the three Ionic liquids have been developed and the apparatus and workshop also been set up.(3) The purity of the ionic liquids have been analyzed and characterized, and a detection method was established. Additionally, the effective quality control have achieved in the synthesizing process of the ionic liquids.