title: Reversible capture of SO2 through functionalized ionic liquids.
abstract: Emission of SO2 in flue gas from the combustion of fossil fuels leads to severe environmental problems. Exploration of green and efficient methods to capture SO2 is an interesting topic, especially at lower SO2 partial pressures. In this work, ionic liquids (ILs) 1-(2-diethylaminoethyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Et2 NEMim][Tf2 N]) and 1-(2-diethylaminoethyl)-3-methylimidazolium tetrazolate ([Et2 NEMim][Tetz]) were synthesized. The performances of the two ILs to capture SO2 were studied under different conditions. It was demonstrated that the ILs were very efficient for SO2 absorption. The [Et2 NEMim][Tetz] IL designed in this work could absorb 0.47 g(SO2)g(IL)(-1) at 0.0101 MPa SO2 partial pressure, which is the highest capacity reported to date under the same conditions. The main reason for the large capacity was that both the cation and the anion could capture SO2 chemically. In addition, the IL could easily be regenerated, and the very high absorption capacity and rapid absorption/desorption rates were not changed over five repeated cycles.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing, PR China.
authors.forename: Dezhong
authors.initials: D
authors.lastname: Yang
authors.forename: Minqiang
authors.initials: M
authors.lastname: Hou
authors.forename: Hui
authors.initials: H
authors.lastname: Ning
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.forename: Xinchen
authors.initials: X
authors.lastname: Kang
authors.forename: Jianling
authors.initials: J
authors.lastname: Zhang
authors.forename: Buxing
authors.initials: B
authors.lastname: Han
mesh_terms: D000042:Absorption; D002245:Carbon Dioxide / Q000737:chemistry / Q000302:isolation & purification; D007093:Imidazoles / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry*; D011312:Pressure; D013458:Sulfur Dioxide / Q000737:chemistry* / Q000302:isolation & purification*; D013696:Temperature; D013997:Time Factors
chemical_list: D007093:Imidazoles; D052578:Ionic Liquids; D013458:Sulfur Dioxide; D002245:Carbon Dioxide
keywords: absorption; green chemistry; ionic liquids; reversibility; sulfur dioxide