title: Absorption of NO and NO2in caprolactam tetrabutyl ammonium halide ionic liquids.
abstract: To explore environmentally benign solvents for the absorption of NO and NO2, a series of caprolactam tetrabutyl ammonium halide ionic liquids were synthesized. The solubility of NO and NO2 was measured at temperatures ranging from 298.2 to 363.2 K and atmospheric pressure, and the following trend in the solubility of NO and NO2 in ionic liquids with various halide anions was observed, respectively: F > Br > Cl and Br > Cl > F. Moreover, as the temperature increased from 308.15 to 363.15 K and the mole ratio of caprolactam increased from 2:1 to 6:1, the solubility of NO increased. Alternatively, the solubility of NO2 decreased as the temperature increased from 298.15 to 363.15 K, and the mole ratio of caprolactam increased from 2:1 to 6:1. The absorption and desorption of NO and NO2 was practically reversible in the ionic liquids, which was characterized by nuclear magnetic resonance. The method, which is at least partially reversible, offers interesting possibilities for the removal of NO and NO2.
authors.affiliation: School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, 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: Dandan
authors.initials: D
authors.lastname: Zhang
authors.forename: Long
authors.initials: L
authors.lastname: Shi
authors.forename: Hua
authors.initials: H
authors.lastname: Sun
authors.forename: Yanan
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000393:Air Pollutants / Q000737:chemistry*; D000397:Air Pollution / Q000517:prevention & control; D002209:Caprolactam / Q000737:chemistry; D003902:Detergents / Q000737:chemistry; D006801:Humans; D009569:Nitric Oxide / Q000737:chemistry*; D009585:Nitrogen Dioxide / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012995:Solubility; D012997:Solvents / Q000737:chemistry
chemical_list: D000393:Air Pollutants; D003902:Detergents; D000644:Quaternary Ammonium Compounds; D012997:Solvents; D009569:Nitric Oxide; D002209:Caprolactam; C009405:tetrabutylammonium; D009585:Nitrogen Dioxide