Abstract:
In this paper, in order to study the potential impact of supported ionic liquids on CO
2 adsorption, the specific ionic liquids (NH
2p-mimX:X= Br
-,PF
6-,BF
4-,NTf
2-) were immobilized in different supports, such as active carbon (AC), silica(SiO
2) and alumina(Al
2O
3) via an impregnation-vaporization method. The supported ionic liquids were characterized by flourier transform infrared(FT-IR) spectrometry,elemental analysis(EA),thermogravimetry-differential thermal analysis(TG-DTA) and so on. The performance of supported ionic liquids for CO
2 adsorption were investigated,and the The effects of using supports with different chemical structures and different anions on the CO
2 adsorption capacity of supported ionic liquids have been studied. The results show that the supported ionic liquids prepared with Al
2O
3 exhibits a high affinity for CO
2 compared with those on SiO
2 and AC. FT-IR analysis indicates that this behavior is due to the excellent dispersing effect of supports on the ionic liquids and the weak interaction between ionic liquids and supports, the latter increases the active sites of ionic liquids for CO
2 adsorption after being loaded. The supported ionic liquids prepared with Al
2O
3 have a relatively large electron density of atomic N of amino, which is favourable to the reaction of CO
2 with –NH
2 of NH
2p-mimBr/Al
2O
3. The CO
2 adsorption performance of supported ionic liquids increases with the increase of the viscosity of ionic liquids and reduces with the increase of volume of ionic liquids.