title: Efficient capture of SO2 by a binary mixture of caprolactam tetrabutyl ammonium bromide ionic liquid and water.
abstract: The solubility of SO(2) in a binary mixture of water and caprolactam tetrabutyl ammonium bromide ionic liquid (CPL-TBAB IL) was investigated. Though the ionic liquid and water were fully miscible, a phase separation occurred when SO(2) was introduced into the mixture. The SO(2) concentrated in the lower layer, and it could be released by heating the solution under reduced pressure (382.2K, 10.1 kPa). After desorption, the mixture could be reused to absorb SO(2). It was found that SO(2) acts as a switch to cause the water and CPL-TBAB IL to phase separate, and the mechanics of this phase separation process was studied by gas chromatography-mass spectrometry, fourier transform-infrared spectroscopy and Karl-Fisher titration. The absorption and desorption of SO(2) in the CPL-TBAB/water mixtures were reversible.
authors.affiliation: School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei 050018, People's Republic of China.
authors.forename: Erhong
authors.initials: E
authors.lastname: Duan
authors.forename: Bin
authors.initials: B
authors.lastname: Guo
authors.forename: Miaomiao
authors.initials: M
authors.lastname: Zhang
authors.forename: Yanan
authors.initials: Y
authors.lastname: Guan
authors.forename: Hua
authors.initials: H
authors.lastname: Sun
authors.forename: Jing
authors.initials: J
authors.lastname: Han
mesh_terms: D001965:Bromides / Q000737:chemistry*; D002209:Caprolactam / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013458:Sulfur Dioxide / Q000737:chemistry*
chemical_list: D001965:Bromides; D052578:Ionic Liquids; D000644:Quaternary Ammonium Compounds; D013458:Sulfur Dioxide; D002209:Caprolactam; C051470:ammonium bromide