Quantitative Spectroscopic Study of Equilibrium in CO2-Loaded Aqueous 2-(Ethylamino)ethanol Solutions

详细信息    查看全文

• 作者：Hidetaka Yamada ; Yoichi Matsuzaki ; Kazuya Goto
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2014
• 出版时间：January 29, 2014
• 年：2014
• 卷：53
• 期：4
• 页码：1617-1623
• 全文大小：341K
• ISSN：1520-5045

文摘

The chemical absorption of CO₂ in aqueous solutions of 2-(ethylamino)ethanol at 313 K was investigated by nuclear magnetic resonance (NMR) spectroscopy. Accurate ¹³C NMR quantitation by inverse-gated decoupling was achieved on the basis of ¹³C spin鈥搇attice relaxation time measurements for all species in the system. The concentration of carbonate species (HCO₃^{鈥?/sup>/CO₃2鈥?/sup>) monotonically increased with increasing CO₂ loading, whereas that of carbamate anion [CH₃CH₂N(CH₂CH₂OH)COO鈥?/sup>] showed a peak around 0.5 mol of CO₂/mol of amine. Furthermore, we found that alkyl carbonate species (CH₃CH₂NHCH₂CH₂OCOO鈥?/sup>) formed in the high-CO₂ loading range, which was confirmed by 2D NMR spectroscopy and density functional theory calculations with a dielectric continuum solvation model at the B3LYP/aug-cc-pVDZ//B3LYP/6-311++G(d,p) level.}