Reaction of aqueous 2-(N-methylamino)ethanol solutions with carbon dioxide. Chemical species and their conformation studied by vibrational spectroscopy and ab initio theories

Journal Article · Thu May 27 04:00:00 EDT 1999 · Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory

DOI:https://doi.org/10.1021/jp984821q· OSTI ID:351565

Ohno, Keiichi; Inoue, Yutaka; Yoshida, Hiroshi; Matsuura, Hiroatsu ^[1]

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1. Hiroshima Univ., Kagamiyama, Higashi-Hiroshima (Japan). Dept. of Chemistry

The recovery and removal of carbon dioxide from flue gases by using CO{sub 2}-amine-H{sub 2}O systems have been of fundamental interest and industrial importance in the problem of preventing global warming. The reaction systems of aqueous 2-(N-methylamino)ethanol (MAE) solutions with dissolved CO{sub 2} (CO{sub 2}-MAE-H{sub 2}O system) and of liquid MAE with dissolved CO{sub 2} (CO{sub 2}-MAE system) have been studied by vibrational spectroscopy and ab initio theories. The chemical species, molecular conformations, and intramolecular and intermolecular hydrogen bonding in these systems have been elucidated. The species produced in the CO{sub 2}-MAE-H{sub 2}O system are the carbamate anion (MAECO{sub 2}{sup {minus}}), the protonated cation (MAEH{sup +}), hydrogencarbonate ion (HCO{sub 3}{sup {minus}}), and carbonate ion (CO{sub 3}{sup 2{minus}}) while the species produced in the CO{sub 2}-MAE system are MAECO{sub 2}{sup {minus}} and MAEH{sup +}. In the CO{sub 2}-MAE-H{sub 2}O system, MAE (secondary amine) reacts with CO{sub 2} to form MAECO{sub 2}{sup {minus}} and MAEH{sup +}, and MAECO{sub 2}{sup {minus}} subsequently reacts with H{sub 2}O and CO{sub 2} to form MAEH{sup +} and HCO{sub 3}{sup {minus}}. This reaction mechanism is contrasted with the mechanism for 2-(N,N-dimethylamino)ethanol (DMAE, tertiary amine), which reacts with CO{sub 2} and H{sub 2}O to form directly DMAEH{sup +} and HCO{sub 3}{sup {minus}}.

• OSTI ID: 351565
• Journal Information: Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory, Journal Name: Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory Journal Issue: 21 Vol. 103; ISSN 1089-5639; ISSN JPCAFH
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
54 ENVIRONMENTAL SCIENCES
AIR POLLUTION CONTROL
AMINES
AQUEOUS SOLUTIONS
CARBON DIOXIDE
CHEMICAL REACTIONS
ETHANOL
INFRARED SPECTRA
QUANTUM MECHANICS
RAMAN SPECTROSCOPY