To discover the SO2 adsorption laws of ionic liquids in simulating flue gas, the SO2 adsorbents 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), 1-butyl-3-methylimidazolium nitrate ([Bmim]NO3), 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) and 1-amyl-3-methylimidazolium chloride [C5mim]Cl ionic liquids were synthesized. The performances were studied under different conditions and the general rules of regeneration were explored. And the diversification of [Bmim]Cl chemical structures, which were pre-desulfated, post-desulfated and post-regenerated, were characterized by Fourier Transform Infrared Spectroscopy. The results illustrated that these ionic liquids all had the ability of SO2 adsorption, and the order of SO2 adsorption performances was [C5mim]Cl>[Bmim]Cl>[Bmim]NO3>[Bmim]BF4. The total SO2 adsorption amount of [C5mim]Cl was 200.8 mg/g, and the optimal adsorption temperature of [Bmim]Cl was 40℃. The order of anions impacting adsorption performances of ionic liquids was Cl->NO-3>BF-4.The sulfur capacity of ionic liquids decreased to 26.5 mg/g from 65.9 mg/g after desorption under the condition of heating(90℃), vacuum(0.09 MPa) and 4.0 h. In addition, the chemical structures of ionic liquid had changed, and the forms of SO2 adsorbed by [Bmim]Cl were physico-chemical processes. |