NMR Speciation of Aqueous MAPA, Tertiary Amines, and Their Blends in the Presence of CO2: Influence of pKa and Reaction Mechanisms
| Autor: | Klaus-Joachim Jens, Diego Di Domenico Pinto, Ida Mortensen Bernhardsen, Hanna K. Knuutila, Cristina Perinu |
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| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Reaction mechanism
Aqueous solution Tertiary amine General Chemical Engineering Propylamine 02 engineering and technology General Chemistry Carbon-13 NMR 021001 nanoscience & nanotechnology Industrial and Manufacturing Engineering chemistry.chemical_compound 020401 chemical engineering chemistry Diamine Desorption Amine gas treating 0204 chemical engineering 0210 nano-technology Nuclear chemistry |
| Zdroj: | Industrial & Engineering Chemistry Research |
| Popis: | The diamine 3-(methylamino)propylamine (MAPA) and eight tertiary amines were studied as single and blended aqueous CO2 absorbents at different concentrations and ratios to investigate their reaction mechanisms. After absorption (40 °C) and desorption (80 °C) experiments, quantitative 13C NMR experiments were performed on each liquid sample. After absorption, the following CO2-derived species were identified and quantified: (bi)carbonate in each amine system, primary and secondary MAPA carbamate and MAPA dicarbamate in MAPA systems, and tertiary amine carbonate in tertiary amine systems. Concerning desorption, the main CO2 species removed was (bi)carbonate, followed in the blends by MAPA dicarbamate. Since, after CO2 absorption, the concentration of MAPA dicarbamate was negligible in single MAPA and, in the blends, mainly increased at increasing pKa of the tertiary amines, it is concluded that the tertiary amines increase the availability of MAPA species to react further with CO2. MAPA and tertiary amines appear to influence each other also for the CO2 release. © American Chemical Society 2018. This is the authors accepted and refereed manuscript to the article. |
| Databáze: | OpenAIRE |
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