Exploring the influence of the type of anion in imidazolium ionic liquids on its thermal stability

In this research, three kinds of imidazole ionic liquids were selected as the research objects. Among them, 1-butyl-3-methyl-imidazole bis(trifluoromethylsulfonyl)imine ([BMIM][Tf 2 N]) was used for gas adsorption, while 1-butyl-3-methyl-imidazole acetate ([BMIM][Ac]) and 1-butyl-3-methyl-imidazole tetrafluoroborate ([BMIM][BF 4 ]) were used as extractants to replace traditional organic extractants. The thermal stability of three selected ionic liquids was studied, and their decomposition pathway and thermal stability were compared to explore the correlation between them. Thermal decomposition characteristic of [BMIM][Ac], [BMIM][BF 4 ], and [BMIM][Tf 2 N] was analyzed by thermogravimetric analysis. For these three ILs, dynamic thermogravimetric analyses under nitrogen atmosphere were performed using thermal gravimetric analyzer. The TG curve shows that the order of short-term thermal stability of three ionic liquids is [BMIM][Ac]