Pyridine-containing ionic liquids lowly loaded in large mesoporous silica and their rapid CO2 gas adsorption at low partial pressure

Porous Polymer Supported Amino Functionalized Ionic Liquid for Effective CO2 Capture

A decrease in CO₂ emissions is urgently required in the present situation due to the fast growth of carbon dioxide (CO₂) in the atmosphere, which has caused a series of global climate issues. This study used an impregnation-evaporation method to immobilize an amino functionalized ionic liquid [C₂OHmim][Lys] on a chromatographic column filler GDX-103 and create a novel supported ionic liquid. The results showed that the supported ionic liquid with 60 wt % ionic liquid content had the best adsorption performance at 40 °C, and the CO₂ adsorption isotherm showed that the adsorption capacity at 0.1 MPa was 1.29 mmol CO₂/g sorbent, which was 6 times greater than the adsorption capacity of the pure carrier. The sample with 60% ionic liquid content has an adsorption capacity of 1.02 mmol CO₂/g sorbent under the condition of CO₂/N₂ mixed gas with 10% CO₂ content. This is 43 times greater than the adsorption capacity of the pure carrier, and its adsorption performance is stable after three adsorption and desorption cycles. Through the rich porous structure of GDX-103, the ionic liquid is effectively supported and dispersed, which expands the contact area between CO₂ and ionic liquid and enhances the mass transfer of CO₂. At the same time, CO₂ can be chemically bound to the groups on the anion of ionic liquid and be immobilized, so it has a high selective adsorption capacity of CO₂, which makes it a great alternative to traditional CO₂ adsorbents.

Tuning Functionalized Ionic Liquids for CO2 Capture

The increasing concentration of CO₂ in the atmosphere is related to global climate change. Carbon capture, utilization, and storage (CCUS) is an important technology to reduce CO₂ emissions and to deal with global climate change. The development of new materials and technologies for efficient CO₂ capture has received increasing attention among global researchers. Ionic liquids (ILs), especially functionalized ILs, with such unique properties as almost no vapor pressure, thermal- and chemical-stability, non-flammability, and tunable properties, have been used in CCUS with great interest. This paper focuses on the development of functionalized ILs for CO₂ capture in the past decade (2012~2022). Functionalized ILs, or task-specific ILs, are ILs with active sites on cations or/and anions. The main contents include three parts: cation-functionalized ILs, anion-functionalized ILs, and cation-anion dual-functionalized ILs for CO₂ capture. In addition, classification, structures, and synthesis of functionalized ILs are also summarized. Finally, future directions, concerns, and prospects for functionalized ILs in CCUS are discussed. This review is beneficial for researchers to obtain an overall understanding of CO₂-philic ILs. This work will open a door to develop novel IL-based solvents and materials for the capture and separation of other gases, such as SO₂, H₂S, NOx, NH₃, and so on.

Rational design of efficient deep eutectic solvents for HCl absorption through their competitive H-bonding interactions

The high reversible solubility of HCl in BmimCl-TAA depends on its competitive hydrogen bond interactions and dynamic structural changes.

Choline-Based Ionic Liquids-Incorporated IRMOF-1 for H2S/CH4 Capture: Insight from Molecular Dynamics Simulation

The removal of H2S and CH4 from natural gas is crucial as H2S causes environmental contamination, corrodes the gas stream pipelines, and decreases the feedstock for industrial productions. Many scientific researches have shown that the metal-organic framework (MOF)/ionic liquids (ILs) have great potential as alternative adsorbents to capture H2S. In this work, molecular dynamics (MD) simulation was carried out to determine the stability of ILs/IRMOF-1 as well as to study the solubility of H2S and CH4 gases in this ILs/IRMOF-1 hybrid material. Three choline-based ILs were incorporated into IRMOF-1 with different ratios of 0.4, 0.8, and 1.2% w/w, respectively, in which the most stable choline-based ILs/IRMOF-1 composite was analysed for H2S/CH4 solubility selectivity. Among the three choline-based ILs/IRMOF-1, [Chl] [SCN]/IRMOF-1 shows the most stable incorporation. However, the increment of ILs loaded in the IRMOF-1 significantly reduced the stability of the hybrid due to the crowding effect. Solvation free energy was then computed to determine the solubility of H2S and CH4 in the [Chl] [SCN]/IRMOF-1. H2S showed higher solubility compared to CH4, where its solubility declined with the increase of choline-based IL loading.