1
|
Tanis I, Brown D, Neyertz S, Vaidya M, Ballaguet JP, Duval S, Bahamdan A. A Molecular Dynamics Study of Single-Gas and Mixed-Gas N 2 and CH 4 Transport in Triptycene-Based Polyimide Membranes. Polymers (Basel) 2023; 15:3811. [PMID: 37765665 PMCID: PMC10535442 DOI: 10.3390/polym15183811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/04/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
Fluorinated polyimides incorporated with triptycene units have gained growing attention over the last decade since they present potentially interesting selectivities and a higher free volume with respect to their triptycene-free counterparts. This work examines the transport of single-gas and mixed-gas N2 and CH4 in the triptycene-based 6FDA-BAPT homopolyimide and in a block 15,000 g mol-1/15,000 g mol-1 6FDA-mPDA/BAPT copolyimide by using molecular dynamics (MD) simulations. The void-space analyses reveal that, while the free volume consists of small-to-medium holes in the 6FDA-BAPT homopolyimide, there are more medium-to-large holes in the 6FDA-mPDA/BAPT copolyimide. The single-gas sorption isotherms for N2 and CH4 over the 0-70 bar range at 338.5 K show that both gases are more soluble in the block copolyimide, with a higher affinity for methane. CH4 favours sites with the most favourable energetic interactions, while N2 probes more sites in the matrices. The volume swellings remain limited since neither N2 nor CH4 plasticise penetrants. The transport of a binary-gas 2:1 CH4/N2 mixture is also examined in both polyimides under operating conditions similar to those used in current natural gas processing, i.e., at 65.5 bar and 338.5 K. In the mixed-gas simulations, the solubility selectivities in favour of CH4 are enhanced similarly in both matrices. Although diffusion is higher in 6FDA-BAPT/6FDA-mPDA, the diffusion selectivities are also close. Both triptycene-based polyimides under study favour, to a similar extent, the transport of methane over that of nitrogen under the conditions studied.
Collapse
Affiliation(s)
- Ioannis Tanis
- Univ. Savoie Mont Blanc, Univ. Grenoble Alpes, CNRS, Grenoble INP, LEPMI, 38000 Grenoble, France; (D.B.); (S.N.)
| | - David Brown
- Univ. Savoie Mont Blanc, Univ. Grenoble Alpes, CNRS, Grenoble INP, LEPMI, 38000 Grenoble, France; (D.B.); (S.N.)
| | - Sylvie Neyertz
- Univ. Savoie Mont Blanc, Univ. Grenoble Alpes, CNRS, Grenoble INP, LEPMI, 38000 Grenoble, France; (D.B.); (S.N.)
| | - Milind Vaidya
- Saudi Aramco, Research & Development Center, P.O. Box 62, Dhahran 31311, Saudi Arabia; (M.V.); (J.-P.B.); (S.D.); (A.B.)
| | - Jean-Pierre Ballaguet
- Saudi Aramco, Research & Development Center, P.O. Box 62, Dhahran 31311, Saudi Arabia; (M.V.); (J.-P.B.); (S.D.); (A.B.)
| | - Sebastien Duval
- Saudi Aramco, Research & Development Center, P.O. Box 62, Dhahran 31311, Saudi Arabia; (M.V.); (J.-P.B.); (S.D.); (A.B.)
| | - Ahmad Bahamdan
- Saudi Aramco, Research & Development Center, P.O. Box 62, Dhahran 31311, Saudi Arabia; (M.V.); (J.-P.B.); (S.D.); (A.B.)
| |
Collapse
|
2
|
Polymer Membranes of Zeolitic Imidazole Framework-8 with Sodium Alginate Synthesized from ZIF-8 and Their Application in Light Gas Separation. Polymers (Basel) 2023; 15:polym15041011. [PMID: 36850293 PMCID: PMC9964549 DOI: 10.3390/polym15041011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 01/29/2023] [Accepted: 02/09/2023] [Indexed: 02/22/2023] Open
Abstract
The potential of nanocomposite membranes (NCMs) prepared by the sodium alginate polymer and embedded with synthesized zeolitic imidazole framework-8 (ZIF-8) as fillers having microporous structure in the application of separation of gaseous mixture generated by the process of methane reforming was assessed. ZIF-8 crystals were created through hydrothermal synthesis, with sizes varying from 50 to 70 nm. NCMs were prepared with a 15% filler loading, i.e., synthesized ZIF-8. NCMs (ZIF-8) having H2 permeability of 28 Barrer and H2/CH4 selectivity of 125 outperformed neat polymer membranes in terms of separation performance at ambient temperature and 4 kg/cm2 pressure. The purity of H2 increased to as high as 95% among the measured values. The NCMs did not, however, outperform a neat polymer membrane in terms of their ability to separate mixtures of gases. Moreover, the combination of ZIF-8 as a filler with sodium alginate was new and had not been reported previously. As a result, it is worthwhile to investigate.
Collapse
|
3
|
Tanvidkar P, Jonnalagedda A, Kuncharam BVR. Fabrication and testing of mixed matrix membranes of
UiO‐66‐NH
2
in cellulose acetate for
CO
2
separation from model biogas. J Appl Polym Sci 2022. [DOI: 10.1002/app.53264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Priya Tanvidkar
- Department of Chemical Engineering Birla Institute of Technology and Science Pilani India
| | - Aditya Jonnalagedda
- Department of Chemical Engineering Birla Institute of Technology and Science Pilani India
| | | |
Collapse
|