Chitosan Containing Supported Ionic Liquid Phase Materials for CO₂ Absorption

Abstract

Here we present novel CO2 sorbents based on chitosan ionogels. The powder sorbents called inverse supported ionic liquid phase (SILP) materials were prepared by dissolving chitosan in various ionic liquids (ILs) followed by encapsulation of the ionogel droplets with nanoporous fumed silica. CO2 absorption was determined at 40 °C in the range of 200 to 5500 mbar. At 1 bar, absorption capacities of these materials were 0.1–0.8 mol kg–1; at 5 bar, values of 0.2–1.5 mol kg–1 were reached. A comparison of inverse SILP materials with and without chitosan dissolved in the applied IL indicated that the presence of chitosan increased the CO2 absorption efficiency of the materials. The aim of the study was also to compare the CO2 absorption in pure chitosan and chitosan dissolved in ILs. It was found that dissolution increases the absorption capacity of chitosan about 10 times.

Carbohydrate-supramolecular gels: Adsorbents for chromium(VI) removal from wastewater

“…In addition to the absence of volatility and flammability of the IL, ionogels can be more conductive and thermally stable. [26][27][28] Similarly, the structural versatility of ionogels allows their application in various fields, including biomedicine, [29] as anti-oxidants, [30] in environmental remediation [31][32][33] and in catalysis. [34] Herein we propose the use of easily synthesisable organic salts as gelators.…”

Access to cross-linked chitosans by exploiting CO2 and the double solvent-catalytic effect of ionic liquids

“…18,19 While ILs have been under investigation for quite some time as CO 2 capture systems, 20 only a few recent reports studied CO 2 , ILs, and chitosan, at the same time. In particular, in one case CO 2 was used as antisolvent to regenerate chitosan from ILs-chitosan solutions, 21 while in other works, ILs-chitosan systems were studied either as reversible CO 2 sorbents, in solutions 22,23 or after immobilization on silica gel, 24 or as a catalytic system for the conversion of CO 2 and MeOH in dimethylcarbonates. 25 A slightly different approach instead employed a hybrid chitosan functionalized IL as a supported catalyst for cycloaddition of CO 2 .…”

Highly Efficient and Convenient Supported Ionic Liquid TiCl5-DMIL@SiO2@Fe3O4-Catalyzed Cycloaddition of CO2 and Epoxides to Cyclic Carbonates

“…Figure 5 showed the diffuse reflectance UV-Vis spectra of the supported ILs. All the supported ILs exhibit a peak around 215 nm, which are assigned to the O-Si transition [38,41]. In addition to this peak, another peaks appeared at around 413, 492, 556 nm in Fig.…”

“…Immobilized ILs have the attractive features of ILs and heterogeneous catalysis, such as easy catalyst recovery, high efficiency, high stability and recyclability. Thus, this problem can be overcome by immobilizing the traditional IL on solid supports [38][39][40][41][42][43][44][45][46]. Various methods have been developed for immobilization of ILs on solid supports such as alumina, titania, silica, etc, and among these solid supports, silica was found to be one of the most effective one [41].…”