Ionic Liquids as Liquid and Solid Sorbents for Post...
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Ionic Liquids as Liquid and Solid Sorbents for Post- Combustion CO 2 Capture Summary The limitations associated with amine solutions for post-combustion CO 2 capture have motivated researchers to find their possible replacement. Ionic liquids (ILs) are considered to be attractive alternatives for post-combustion CO 2 capture because of their many unique properties. ILs possess high thermal stability, wide liquid range, negligible vapour pressure and tunable physicochemical properties making robust materials for CO 2 capture technologies [1]. We have developed functionalized ILs that are potential greener alternative to amine solutions for post-combustion CO 2 capture. Physicochemical properties of the novel selected ILs including density, viscosity, thermal analysis etc. were evaluated. CO 2 capture performance of the ILs was evaluated both as (i) neat liquid sorbents [2] and (ii) solid sorbents by immobilizing ILs on porous materials [3]. These novel ILs have shown CO 2 capture performance of more than 1 mol of CO 2 /mol of IL, up to 25 wt % of CO 2 at atmospheric pressure. NMR and IR spectroscopic techniques have confirmed the chemisorption of CO 2 by these ILs. NMR self-diffusion study revealed a significant change in the diffusion behaviour of IL upon CO 2 capture. The immobilized ILs into porous materials revealed promising CO 2 capture capacity. ILs supported on porous materials were characterized by various techniques including powder XRD, solid-state NMR spectroscopy and thermal analysis. Solid-state NMR spectroscopy confirmed strong interactions between ILs and the porous materials. ILs behaved like a solid on the surface of the porous materials. This study suggests that the film formation between IL and surface of porous material is a complex process involving various chemical reactions at the interfaces. These findings can be important for understanding the mechanisms of immobilization of ILs on the surfaces of porous materials. Acknowledgment The Norrbotten Research Council (NoFo) and the Swedish Research Council are gratefully acknowledged for the financial support of this project. Faiz Ullah Shah a , Shubhankar Bhattacharyya a , Andrei Filippov a and Farid Akhtar b a Chemistry of Interfaces, Luleå University of Technology, SE-97187 Luleå, Sweden b Division of Material Science, Luleå University of Technology, SE-97187 Luleå, Sweden 1. Z. Lei, C. Dai, B. Chen. Gas solubility in ionic liquids. Chem. Rev. 2014, 114, 1289−1326. 2. S. Bhattacharyya, A. Filippov, F. U. Shah. Functionalized ionic liquids for CO 2 capture (to be submitted). 3. F. U. Shah, F. Akhtar. Ionic liquids supported on porous materials for post-combustion CO 2 capture (to be submitted). To investigate new ionic liquids as neat liquid sorbents and as solid sorbents supported on porous materials. To study the interactions between ionic liquids and solid porous materials using solid-state MAS NMR spectroscopy and other characterization techniques. In addition, to further understand the mechanism of CO 2 molecule interaction with various ionic liquids. Aims of the study References N OH CH 3 CH 3 P H 3 C CH 3 H 3 C H 3 C H 3 C NH 2 OH O O O CH 3 O NH 2 OH N N [N 1,1,6,2OH ] + [P 6,6,6,14 ] + [4-AmSc] - [Threo] - [Imi] - Figure 3. Powder diffraction XRD of zeolite and [P 6,6,6,14 ][4- AmSc] supported on zeolite. Figure 1. Single-pulse 31 P MAS NMR spectra of [P 6,6,6,14 ][4-AmSc] supported on zeolite. The MAS frequency was 8 kHz and the number of signal transients was 10000. Figure 2. 31 P CP/MAS NMR spectra of [P 6,6,6,14 ][4-AmSc] supported on zeolite. The MAS frequency was 8 kHz and the number of signal transients was 10000. Scheme 1. Structural illustration of the ionic components of ionic liquids. Figure 5. CO 2 adsorption kinetics for [P 6,6,6,14 ][4-AmSc] supported on zeolite. Figure 4. TG curves of [P 6,6,6,14 ][4-AmSc] supported on zeolite. Figure 6. Change of viscosity as a function of temperature for choline based ILs. Figure 7. Change of density as a function of temperature for choline based ILs. Figure 8. CO 2 absorption kinetics of choline based ILs at 20°C (green), 40°C (blue) and 60°C (red).
Transcript of Ionic Liquids as Liquid and Solid Sorbents for Post...
Ionic Liquids as Liquid and Solid Sorbents for Post-Combustion CO2 Capture
Summary The limitations associated with amine solutions for post-combustion CO2 capture have motivated researchers to find their possible replacement. Ionic liquids (ILs) are considered to be attractive alternatives for post-combustion CO2 capture because of their many unique properties. ILs possess high thermal stability, wide liquid range, negligible vapour pressure and tunable physicochemical properties making robust materials for CO2 capture technologies [1]. We have developed functionalized ILs that are potential greener alternative to amine solutions for post-combustion CO2 capture. Physicochemical properties of the novel selected ILs including density, viscosity, thermal analysis etc. were evaluated. CO2 capture performance of the ILs was evaluated both as (i) neat liquid sorbents [2] and (ii) solid sorbents by immobilizing ILs on porous materials [3]. These novel ILs have shown CO2 capture performance of more than 1 mol of CO2/mol of IL, up to 25 wt % of CO2 at atmospheric pressure. NMR and IR spectroscopic techniques have confirmed the chemisorption of CO2 by these ILs. NMR self-diffusion study revealed a significant change in the diffusion behaviour of IL upon CO2 capture. The immobilized ILs into porous materials revealed promising CO2 capture capacity. ILs supported on porous materials were characterized by various techniques including powder XRD, solid-state NMR spectroscopy and thermal analysis. Solid-state NMR spectroscopy confirmed strong interactions between ILs and the porous materials. ILs behaved like a solid on the surface of the porous materials. This study suggests that the film formation between IL and surface of porous material is a complex process involving various chemical reactions at the interfaces. These findings can be important for understanding the mechanisms of immobilization of ILs on the surfaces of porous materials.
Acknowledgment The Norrbotten Research Council (NoFo) and the Swedish Research Council are gratefully acknowledged for the financial support of this project.
Faiz Ullah Shaha, Shubhankar Bhattacharyyaa, Andrei Filippova and Farid Akhtarb aChemistry of Interfaces, Luleå University of Technology, SE-97187 Luleå, Sweden
bDivision of Material Science, Luleå University of Technology, SE-97187 Luleå, Sweden
1. Z. Lei, C. Dai, B. Chen. Gas solubility in ionic liquids. Chem. Rev. 2014, 114, 1289−1326. 2. S. Bhattacharyya, A. Filippov, F. U. Shah. Functionalized ionic liquids for CO2 capture (to be submitted). 3. F. U. Shah, F. Akhtar. Ionic liquids supported on porous materials for post-combustion CO2 capture (to be submitted).
To investigate new ionic liquids as neat liquid sorbents and as solid sorbents supported on porous materials. To study the interactions between ionic liquids and solid porous materials using solid-state MAS NMR spectroscopy and other characterization techniques. In addition, to further understand the mechanism of CO2 molecule interaction with various ionic liquids.
Aims of the study
References
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NOH
CH3
CH3
P
H3C
CH3H3C
H3C
H3C
NH2
OH
OO
O CH3
O
NH2
OH
N N
[N1,1,6,2OH]+
[P6,6,6,14]+
[4-AmSc]- [Threo]- [ Im i ]-
Figure 3. Powder diffraction XRD of zeolite and [P6,6,6,14][4-AmSc] supported on zeolite.
Figure 1. Single-pulse 31P MAS NMR spectra of [P6,6,6,14][4-AmSc] supported on zeolite. The MAS frequency was 8 kHz and the number of signal transients was 10000.
Figure 2. 31P CP/MAS NMR spectra of [P6,6,6,14][4-AmSc] supported on zeolite. The MAS frequency was 8 kHz and the number of signal transients was 10000.
Scheme 1. Structural illustration of the ionic components of ionic liquids.
Figure 5. CO2 adsorption kinetics for [P6,6,6,14][4-AmSc] supported on zeolite.
Figure 4. TG curves of [P6,6,6,14][4-AmSc] supported on zeolite.
Figure 6. Change of viscosity as a function of temperature for choline based ILs.
Figure 7. Change of density as a function of temperature for choline based ILs.
Figure 8. CO2 absorption kinetics of choline based ILs at 20°C (green), 40°C (blue) and 60°C (red).
