1. Beijing Key Laboratory of Ionic Liquids Clean Process, CAS Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China 2. College of Mathematics and Physics, Bohai University, Jinzhou 121013, China 3. School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China 4. Zhengzhou Institute of Emerging Industrial Technology, Zhengzhou 450001, China
Ionic liquid (IL)/polyimide (PI) composite membranes demonstrate promise for use in CO2 separation applications. However, few studies have focused on the microscopic mechanism of CO2 in these composite systems, which is important information for designing new membranes. In this work, a series of systems of CO2 in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide composited with 4,4-(hexafluoroisopropylidene) diphthalic anhydride (6FDA)-based PI, 6FDA-2,3,5,6-tetramethyl-1,4-phenylene-diamine, at different IL concentrations were investigated by all-atom molecular dynamics simulation. The formation of IL regions in PI was found, and the IL regions gradually became continuous channels with increasing IL concentrations. The analysis of the radial distribution functions and hydrogen bond numbers demonstrated that PI had a stronger interaction with cations than anions. However, the hydrogen bonds among PI chains were destroyed by the addition of IL, which was favorable for transporting CO2. Furthermore, the self-diffusion coefficient and free energy barrier suggested that the diffusion coefficient of CO2 decreased with increasing IL concentrations up to 35 wt-% due to the decrease of the fractional free volume of the composite membrane. However, the CO2 self-diffusion coefficients increased when the IL contents were higher than 35 wt-%, which was attributed to the formation of continuous IL domain that benefitted the transportation of CO2.
S Quale, V Rohling. The European carbon dioxide capture and storage laboratory infrastructure (ECCSEL). Green Energy & Environment, 2016, 1(3): 180–194 https://doi.org/10.1016/j.gee.2016.11.007
3
M E Boothandford, J C Abanades, E J Anthony, M J Blunt, S Brandani, N M Dowell, J R Fernandez, M Ferrari, R Gross, J P Hallett. Carbon capture and storage update. Energy & Environmental Science, 2014, 7(1): 130–189 https://doi.org/10.1039/C3EE42350F
M Li, X Jiang, G He. Application of membrane separation technology in postcombustion carbon dioxide capture process. Frontiers of Chemical Science and Engineering, 2014, 8(2): 233–239 https://doi.org/10.1007/s11705-014-1408-z
6
S Kanehashi, C A Scholes. Perspective of mixed matrix membranes for carbon capture. Frontiers of Chemical Science and Engineering, 2020, 14(3): 1–10 https://doi.org/10.1007/s11705-019-1881-5
7
S Pandiyan, D Brown, S Neyertz, N F A van der Vegt. Carbon dioxide solubility in three fluorinated polyimides studied by molecular dynamics simulations. Macromolecules, 2010, 43(5): 2605–2621 https://doi.org/10.1021/ma902507d
8
H Tong, C Hu, S Yang, Y Ma, H Guo, L Fan. Preparation of fluorinated polyimides with bulky structure and their gas separation performance correlated with microstructure. Polymer, 2015, 69: 138–147 https://doi.org/10.1016/j.polymer.2015.05.045
9
K E O’Harra, I Kammakakam, E M Devriese, D M Noll, J E Bara, E M Jackson. Synthesis and performance of 6FDA-based polyimide-ionenes and composites with ionic liquids as gas separation membranes. Membranes, 2019, 9(7): 79–96 https://doi.org/10.3390/membranes9070079
10
S Kanehashi, M Kishida, T Kidesaki, R Shindo, S Sato, T Miyakoshi, K Nagai. CO2 separation properties of a glassy aromatic polyimide composite membranes containing high-content 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid. Journal of Membrane Science, 2013, 430: 211–222 https://doi.org/10.1016/j.memsci.2012.12.003
11
F Weigelt, S Escorihuela, A Descalzo, A Tena, S Escolastico, S Shishatskiy, J M Serra, T Brinkmann. Novel polymeric thin-film composite membranes for high-temperature gas separations. Membranes, 2019, 9(4): 51–64 https://doi.org/10.3390/membranes9040051
12
X Zhang, H Feng, Z Liu, W Wang, E J Maginn. Absorption of CO2 in the ionic liquid 1-n-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate ([Hmim][FEP]): a molecular view by computer simulations. Journal of Physical Chemistry B, 2009, 113(21): 7591–7598 https://doi.org/10.1021/jp900403q
13
X Zhang, Z Liu, W Wang. Screening of ionic liquids to capture CO2 by COSMO-RS and experiments. AIChE Journal. American Institute of Chemical Engineers, 2008, 54(10): 2717–2728 https://doi.org/10.1002/aic.11573
14
A Haghtalab, A Shojaeian. High pressure measurement and thermodynamic modelling of the solubility of carbon dioxide in N-methyldiethanolamine and 1-butyl-3-methylimidazolium acetate mixture. Journal of Chemical Thermodynamics, 2015, 81: 237–244 https://doi.org/10.1016/j.jct.2014.10.011
15
A H Jalili, A Mehdizadeh, M Shokouhi, H Sakhaeinia, V Taghikhani. Solubility of CO2 in 1-(2-hydroxyethyl)-3-methylimidazolium ionic liquids with different anions. Journal of Chemical Thermodynamics, 2010, 42(6): 787–791 https://doi.org/10.1016/j.jct.2010.02.002
16
X Lei, Y Xu, L Zhu, X Wang. Highly efficient and reversible CO2 capture through 1,1,3,3-tetramethylguanidinium imidazole ionic liquid. RSC Advances, 2014, 4(14): 7052–7054 https://doi.org/10.1039/c3ra47524g
17
J Wang, S Zeng, F Huo, D Shang, H He, L Bai, X Zhang, J Li. Metal chloride anion-based ionic liquids for efficient separation of NH3. Journal of Cleaner Production, 2019, 206: 661–669 https://doi.org/10.1016/j.jclepro.2018.09.192
18
P Li, M R Coleman. Synthesis of room temperature ionic liquids based random copolyimides for gas separation applications. European Polymer Journal, 2013, 49(2): 482–491 https://doi.org/10.1016/j.eurpolymj.2012.11.016
19
M S Mittenthal, B S Flowers, J E Bara, J W Whitley, S K Spear, J D Roveda, D A Wallace, M S Shannon, R Holler, R Martens, D T Daly. Ionic polyimides: hybrid polymer architectures and composites with ionic liquids for advanced gas separation membranes. Industrial & Engineering Chemistry Research, 2017, 56(17): 5055–5069 https://doi.org/10.1021/acs.iecr.7b00462
20
A Ito, T Yasuda, X Ma, M Watanabe. Sulfonated polyimide/ionic liquid composite membranes for carbon dioxide separation. Polymer Journal, 2017, 49(9): 671–676 https://doi.org/10.1038/pj.2017.31
21
B Monteiro, A R Nabais, F A Almeida Paz, L Cabrita, L C Branco, I M Marrucho, L A Neves, C C L Pereira. Membranes with a low loading of metal-organic framework-supported ionic liquids for CO2/N2 separation in CO2 capture. Energy Technology (Weinheim), 2017, 5(12): 2158–2162 https://doi.org/10.1002/ente.201700228
22
M Balçık, M G Ahunbay. Prediction of CO2-induced plasticization pressure in polyimides via atomistic simulations. Journal of Membrane Science, 2018, 547: 146–155 https://doi.org/10.1016/j.memsci.2017.10.038
23
X Zhang, Z Liu, X Liu. Understanding the interactions between tris(pentafluoroethyl)-trifluorophosphate-based ionic liquid and small molecules from molecular dynamics simulation. Science China. Chemistry, 2012, 55(8): 1557–1565 https://doi.org/10.1007/s11426-012-4647-1
24
T C Lourenco, M F Coelho, T C Ramalho, D Van Der Spoel, L T Costa. Insights on the solubility of CO2 in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide from the microscopic point of view. Environmental Science & Technology, 2013, 47(13): 7421–7429 https://doi.org/10.1021/es4020986
25
A Abedini, E Crabtree, J E Bara, C H Turner. Molecular simulation of ionic polyimides and composites with ionic liquids as gas-separation membranes. Langmuir, 2017, 33(42): 11377–11389 https://doi.org/10.1021/acs.langmuir.7b01977
26
D V D Spoel, E Lindahl, B Hess, G Groenhof, H J C Berendsen. GROMACS: fast, flexible, and free. Journal of Computational Chemistry, 2005, 26(16): 1701–1718 https://doi.org/10.1002/jcc.20291
27
B Hess, C Kutzner, D Van Der Spoel, E Lindahl. GROMACS 4: algorithms for highly efficient, load-balanced, and scalable molecular simulation. Journal of Chemical Theory and Computation, 2008, 4(3): 435–447 https://doi.org/10.1021/ct700301q
28
Z P Liu, S P Huang, W C Wang. A refined force field for molecular simulation of imidazolium-based ionic liquids. Journal of Physical Chemistry B, 2004, 108(34): 12978–12989 https://doi.org/10.1021/jp048369o
29
J N C Lopes, A A H Pádua. Molecular force field for ionic liquids composed of triflate or bistriflylimide anions. Journal of Physical Chemistry B, 2004, 108(43): 16893–16898 https://doi.org/10.1021/jp0476545
30
I Tanis, D Brown, S J Neyertz, R Heck, R Mercier. A comparison of homopolymer and block copolymer structure in 6FDA-based polyimides. Physical Chemistry Chemical Physics, 2014, 16(42): 23044–23055 https://doi.org/10.1039/C4CP03039G
31
J Wang, R M Wolf, J W Caldwell, P A Kollman, D A Case. Development and testing of a general amber force field. Journal of Computational Chemistry, 2004, 25(9): 1157–1174 https://doi.org/10.1002/jcc.20035
32
L Martínez, R Andrade, E G Birgin, J M Martínez. PACKMOL: a package for building initial configurations for molecular dynamics simulations. Journal of Computational Chemistry, 2009, 30(13): 2157–2164 https://doi.org/10.1002/jcc.21224
33
U Essmann, L Perera, M L Berkowitz, T Darden, H Lee, L G Pedersen. A smooth particle mesh Ewald method. Journal of Chemical Physics, 1995, 103(19): 8577–8593 https://doi.org/10.1063/1.470117
34
B Hess, H Bekker, H J C Berendsen, J G E M Fraaije. LINCS: a linear constraint solver for molecular simulations. Journal of Chemical Theory and Computation, 1997, 18(12): 1463–1472
35
M Parrinello, A Rahman. Polymorphic transitions in single crystals: a new molecular dynamics method. Journal of Applied Physics, 1981, 52(12): 7182–7190 https://doi.org/10.1063/1.328693
36
C Braga, K P Travis. A configurational temperature Nosé-Hoover thermostat. Journal of Computational Physics, 2005, 123(13): 134101–134116
37
W Shi, E J Maginn. Atomistic simulation of the absorption of carbon dioxide and water in the ionic liquid 1-n-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [hmim] [Tf2N]. Journal of Physical Chemistry B, 2008, 112(7): 2045–2055 https://doi.org/10.1021/jp077223x
38
G M Torrie, J P Valleau. Nonphysical sampling distributions in Monte Carlo free-energy estimation: umbrella sampling. Journal of Computational Physics, 1977, 23(2): 187–199 https://doi.org/10.1016/0021-9991(77)90121-8
39
S Kumar, J M Rosenberg, D Bouzida, R H Swendsen, P A Kollman. The weighted histogram analysis method for free-energy calculations on biomolecules. I. The method. Journal of Computational Chemistry, 1992, 13(8): 1011–1021 https://doi.org/10.1002/jcc.540130812
40
Y Wang, C Wang, Y Zhang, F Huo, H He, S Zhang. Molecular insights into the regulatable interfacial property and flow behavior of confined ionic liquids in graphene nanochannels. Small, 2019, 15(29): 1804508–1804518 https://doi.org/10.1002/smll.201804508
41
D L Sun, J Zhou. Ionic liquid confined in nafion: toward molecular-level understanding. AIChE Journal. American Institute of Chemical Engineers, 2013, 59(7): 2630–2639 https://doi.org/10.1002/aic.14009
42
T Song, X Zhang, Y Li, K Jiang, S Zhang, X Cui, L Bai. Separation efficiency of CO2 in ionic liquids/poly(vinylidene fluoride) composite membrane: a molecular dynamics study. Industrial & Engineering Chemistry Research, 2019, 58(16): 6887–6898 https://doi.org/10.1021/acs.iecr.8b06100
43
X Zhang, F Huo, X Liu, K Dong, H He, X Yao, S Zhang. Influence of microstructure and interaction on viscosity of ionic liquids. Industrial & Engineering Chemistry Research, 2015, 54(13): 3505–3514 https://doi.org/10.1021/acs.iecr.5b00415
W M Lee. Selection of barrier materials from molecular-structure. Polymer Engineering and Science, 1980, 20(1): 65–69 https://doi.org/10.1002/pen.760200111
47
K Tanaka, H Kita, M Okano, K Okamoto. Permeability and permselectivity of gases in fluorinated and non-fluorinated polyimides. Polymer, 1992, 33(3): 585–592 https://doi.org/10.1016/0032-3861(92)90736-G
48
H Cheng, J Zhang, Z Qi. Effects of interaction with sulphur compounds and free volume in imidazolium-based ionic liquid on desulphurisation: a molecular dynamics study. Molecular Simulation, 2018, 44(1): 55–62 https://doi.org/10.1080/08927022.2017.1337273
49
L Cantley, J L Swett, D Lloyd, D A Cullen, K Zhou, P V Bedworth, S Heise, A J Rondinone, Z P Xu, S Sinton, J S Bunch. Voltage gated inter-cation selective ion channels from graphene nanopores. Nanoscale, 2019, 11(20): 9856–9861 https://doi.org/10.1039/C8NR10360G
50
K Zhou, Z P Xu. Ion permeability and selectivity in composite nanochannels: engineering through the end effects. Journal of Physical Chemistry C, 2020, 124(8): 4890–4898 https://doi.org/10.1021/acs.jpcc.9b11750
