Diamino protic ionic liquids for CO2 capture

Abstract

A series of multifunctional protic ionic liquids (PILs), some of which are based on a combination of primary and tertiary amines in the same moiety coupled with a carboxylic acid, have been synthesised and employed for CO2 capture, yielding absorption capacities comparable to standard absorbents. In contrast to traditional amine absorbers, CO2 was found to desorb at lower temperatures and hence could result in a significant reduction in both the energy required to strip the absorber of CO2 and the thermally activated degradation mechanisms, which in traditional absorbers result in the loss of absorber and the production of toxic compounds. The lower basicity of the amine sites resultant from PIL formation decreases the binding energy of the CO2 to the absorber. The weaker basicity is also evidenced by lower pH of the PIL CO2 absorbers, which reduces common corrosion problems associated with traditional amine absorbers.

Insights into Carbon Dioxide Electroreduction in Ionic Liquids: Carbon Dioxide Activation and Selectivity Tailored by Ionic Microhabitat

“…Hence, tremendous energy is required to restructure the linear molecule into the nonlinear [CCO 2 ] À radical anion, which occurs at av ery negative potential, that is, À1.9 V versus an ormalhydrogen electrode (NHE). [4] As an ovel type of liquid salt, ionic liquids( ILs), solely consistingo fc ations and anions, exhibit excellent CO 2 solubility, [5] especially functionalized ILs, such as amino-, [6] acetate-, [7] azolate-, [8] pyridine-, [9] and amino acid based ILs. [10] In addition to reports on ILs for CO 2 capture, ILs have also been used as electrolytes for CO 2 electroreduction in recent years.…”

Novel SCS-IL-MP2 and SOS-IL-MP2 Methods for Accurate Energetics of Large-Scale Ionic Liquid Clusters

“…12 In some ionic liquids the delocalised nature of anions may further induce specific dispersion-driven interactions such as π-π stacking as was observed in crystal structures of methanide-based ionic liquids and confirmed by quantum chemical calculations. 13 Large contributions of dispersion to total interaction energy further emphasize that the issue of basis set superposition error (BSSE) in wavefunction-based methods can no longer be ignored in these systems.…”

Properties of ionic liquid mixtures of [NH2e‐mim][BF4] and [bmim][BF4] as absorbents for CO2 capture

“…In order to enhance the performance of conventional imidazolium ILs to capture CO 2 , researchers functionalize them by introducing functional groups into the imidazole ring . Functionalized ILs can chemically react with CO 2 and they can absorb a large amount of CO 2 more quickly than other ILs . For example, in 2002, Davis's group reported the first CO 2 chemisorption by an amine‐functionalized IL ([NH 2 p‐bmim][BF 4 ]), in which 0.5 mol CO 2 per mol of IL could be absorbed.…”

“…10,11 Functionalized ILs can chemically react with CO 2 and they can absorb a large amount of CO 2 more quickly than other ILs. 12,13 For example, in 2002, Davis's group 14 reported the first CO 2 chemisorption by an amine-functionalized IL ([NH 2 p-bmim][BF 4 ]), in which 0.5 mol CO 2 per mol of IL could be absorbed. However, the viscosity of the ILs will be greatly increased after functionalization.…”