title: CO2 absorption and desorption in an aqueous solution of heavily hindered alkanolamine: structural elucidation of CO2-containing species.
abstract: The pathways for the CO2 absorption and desorption in an aqueous solution of a heavily hindered alkanolamine, 2-(t-butylamino)ethanol (TBAE) were elucidated by X-ray crystallographic and (13)C NMR spectroscopic analysis. In the early stage of the CO2 absorption, the formation of carbonate species ([TBAEH]2CO3) was predominant, along with the generation of small amounts of zwitterionic species. With the progress of the absorption, the carbonate species was rapidly transformed into bicarbonate species ([TBAEH]HCO3), and the amounts of the zwitterionic species increased gradually. During desorption at elevated temperature in the absence of CO2, [TBAEH]HCO3 was found to transform into [TBAEH]2CO3, where CO3(2-) strongly interacts with two [TBAEH](+) via hydrogen bondings.
authors.affiliation: Department of Chemistry and Research Institute of Basic Sciences, Kyung Hee University , 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701, Republic of Korea.
authors.forename: Young-Seop
authors.initials: YS
authors.lastname: Choi
authors.forename: Jinkyu
authors.initials: J
authors.lastname: Im
authors.forename: Jun Kyo
authors.initials: JK
authors.lastname: Jeong
authors.forename: Sung Yun
authors.initials: SY
authors.lastname: Hong
authors.forename: Ho Gyeom
authors.initials: HG
authors.lastname: Jang
authors.forename: Minserk
authors.initials: M
authors.lastname: Cheong
authors.forename: Je Seung
authors.initials: JS
authors.lastname: Lee
authors.forename: Hoon Sik
authors.initials: HS
authors.lastname: Kim
mesh_terms: D000042:Absorption; D000588:Amines / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D018360:Crystallography, X-Ray; D000431:Ethanol / Q000737:chemistry; D007477:Ions; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D012996:Solutions; D014867:Water / Q000737:chemistry*
chemical_list: D000588:Amines; D007477:Ions; D012996:Solutions; D014867:Water; D002245:Carbon Dioxide; D000431:Ethanol