Highly efficient SO2 absorption/activation and subsequent utilization by polyethylene glycol-functionalized Lewis basic ionic liquids

Abstract

Up to now, flue-gas desulfurization (FGD) is one of the most effective techniques to control SO(2) emission from the combustion of fossil fuels. The conventional technology for FGD poses serious inherent drawbacks such as formation of byproducts and volatilization of solvents. In this work, polyethylene glycol (PEG)-functionalized Lewis basic ionic liquids (ILs) derived from DABCO were proved to be highly efficient absorbents for FGD due to its specific features such as high thermal stability, negligible vapor pressure, high loading capacity. Notably, PEG(150)MeDABCONTf(2) gave an extremely high SO(2) capacity (4.38 mol mol(-1) IL), even under 0.1 bar SO(2) partial pressure (1.01 mol mol(-1) IL), presumably owing to the strong SO(2)-philic characterization of the PEG chain. Furthermore, the absorbed SO(2) could be easy to release by just bubbling N(2) at room temperature, greatly reducing energy requirement for SO(2) desorption. In addition, SO(2)/CO(2) selectivity (110) of PEG(150)MeDABCONTf(2) is two times larger than the non-functionalized imidazolium IL (45). On the other hand, through activation of SO(2) with the tertiary nitrogen in the cation, Lewis basic ILs such as PEG(150)MeDABCOBr proved to be efficient catalysts for the conversion of SO(2) to some value-added chemicals such as cyclic sulfites without utilization of any organic solvent or additive. Thus, this protocol would pave the way for the development of technological innovation towards efficient and low energy demanded practical process for SO(2) absorption and subsequent transformation.

Amine-Functionalized Covalent Organic Framework for Efficient SO2 Capture with High Reversibility

“…In particular, the ILs functionalized by amine groups have exhibited a very high SO 2 adsorption capacity 14–17 . The chemical interaction between SO 2 and amine groups in the ILs constructs a charge-transfer complex 18, 19 , which forms relatively unstable ionic structure that can reduce the energy requirement for SO 2 desorption 20 .…”

“…In this respect, guanidinium 21–23 , alkanol amine 24 , 1,4-Diazobicyclo[2,2,2]octane (DABCO) 20 , and azole-based ILs 2, 16, 25, 26 have been developed as chemical adsorbents for SO 2 . Even though a number of functional groups have been reported in the IL fields, practical applications have not yet been realized, because there has been a huge drawback which is relatively slow SO 2 absorption rate due to the high viscosity of the ILs 27 .…”

Visible‐Light‐Mediated Addition of α‐Aminoalkyl Radicals to [60]Fullerene by Using Photoredox Catalysts

“…On the other hand, PEG‐functionalized DABCO150 presents a highly reversible SO 2 absorption capability (4.38 mol per mol IL, even under 0.1 bar SO 2 ) and allows the possibility of trapping SO 2 as cyclic sulfites through the addition of a suitable epoxide and activation of this latter by a Lewis base IL (i.e., [PEG 150 Medabco]Br; Scheme ).…”

π-Hole interaction: a theoretical insight into the mechanism of SO2 captured by [Et2NEMim][Tetz] ionic liquids

“…In recent years, more Electronic supplementary material The online version of this article (doi:10.1007/s00894-015-2747-5) contains supplementary material, which is available to authorized users. and more researchers have reported the use of ILs to reversibly capture SO 2 and CO 2 by utilizing both physical and chemical interactions [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. Very recently, Yang and Han et al [26] reported that two functionalized ILs, 1-(2-diethylaminoethyl)-3-methylimidazoliu bis (trifluoromethylsulfonyl)-imide ( A specific intermolecular interaction involving pnicogen, chalcogen and halogen atoms as acceptors of electron density, has been studied extensively in recent years [27][28][29][30][31].…”