13C-NMR Study of Acid Dissociation Constant (pKa) Effects on the CO2 Absorption and Regeneration of Aqueous Alkanolpiperidine. (July 2017)

• Record Type: Journal Article
• Authors: Furukawa, Yukio; Koriki, Hirotaka; Shuto, Daiki; Sato, Hiroshi; Yamanaka, Yasuro
• Is Part Of: Energy procedia. Volume 114(2017)
• Page Start: 1765
• Page End: 1771
• Publication Date: 2017-07
• Subjects: 13C-NMR -- alkanolpiperidine -- acid dissociation constant -- CO2 capture -- CO2 regeneration; Power resources -- Congresses; Power resources -- Periodicals; Power resources; Conference proceedings; Periodicals; 333.7905
• DOI: 10.1016/j.egypro.2017.03.1304
• Languages: English
• ISSNs: 1876-6102

Abstract

Abstract: We have studied the formation rates of HCO3 – /CO3 2–, amine/protonated amine, carbamate/protonated carbamate, and carbonate/protonated carbonate in the course of CO2 absorption at room temperature, and composition changes and CO2 release upon heating at 93 °C for 30 min for aqueous solutions of 9 kinds of alkanolpiperidines using 13 C-NMR spectroscopy. The p K a values of these alkanolpiperidines were measured. The initial CO2 capture rates of alkanolpiperidines do not depend on their p K a values, which is quite different from general trends of aqueous amine absorbents. The CO2 release amount of each alkanolpiperidine increased with decreasing p K a, as a general trend. The CO2 release amounts of 1-HE-PD, 2-HM-1-M-PD, 3-HM-1-M-PD, and 4-HM-1-M-PD increased with increasing concentrations.