Carbon dioxide uptake from natural gas by binary ionic liquid–water mixtures

Abstract

Carbon dioxide solubility in a set of carboxylate ionic liquids formulated with stoicheiometric amounts of water is found to be significantly higher than for other ionic liquids previously reported. This is due to synergistic chemical and physical absorption. The formulated ionic liquid/water mixtures show greatly enhanced carbon dioxide solubility relative to both anhydrous ionic liquids and aqueous ionic liquid solutions, and are competitive with commercial chemical absorbers, such as activated N-methyldiethanolamine or monoethanolamine. † CCDC 1055905 and 1055906. For crystallographic data in CIF or other electronic format see

Tuning the Carbon Dioxide Absorption in Amino Acid Ionic Liquids

“…[19-21, 41, 43, 44] The high viscosities of AAILs before CO 2 absorption and their dramatic increase after CO 2 absorption have led to the investigation of methods to reduce the viscosity, prevent its increase, or both. Mixtures of AAILs with water [27,45,46] or low-viscosity ILs, [47,48] the immobilization of AAILs into porous materials, [16,40,42,49] and AAILs with the possibilities to form intramolecular hydrogen bonds [50] have been considered. However, the available theoretical work deals with density functional theory calculations of several aminefunctionalized anions and cations [51,52] to explain the 1:2 or 1:1 absorption capacity owing to the stabilization or destabilization effect of the cation or anion on the carbamic acid.…”

CO<sub>2</sub> Absorption Performance of “Dry Matter” Prepared with Amino Acid-Based Ionic Liquids

“…82% of aq. MEA solution which was regenerated at 120˚C [10]. As for the reason for the miserably bad results, it may be appropriate to refer to the study by Nagai et al again [17].…”

“…In the case of CO 2 capture by aq. MEA [10] [21], the regeneration of the absorbent has been performed by stripping with water vapor at 100˚C -120˚C. In the present study, CO 2 PAlA maq.…”

“…In the alanine-IL systems, the highest A.A. (mol/mol) was obtained in the absence of water, which is contrastive to the other two systems which showed significant CO 2 absorption in the presence of large amounts of water. As for the alanine system, some literature data are available in addition to that by Anderson et al [10]; according to Jiang et al [3], the mol-base A. to evaluate the recyclability of the DM. Figure 3 and Table 3 show only a typical In order to figure out what caused the higher performance, we first examine the A.A. values of the respective bulk systems.…”

“…However, this conventional procedure has some serious drawbacks, e.g., inevitable loss and emission of those corrosive amines and thermal degradation during the energy-demanding regeneration process of the absorbents [1]. As a promising candidate for CO 2 -absorbing materials, amine-functionalized ionic liquids have recently attracted much attention [1]- [10]. Since ionic liquids (ILs) have favorable properties such as negligible volatility and excellent thermal stability, they are free from some of the above drawbacks.…”