Gas Permeation Unit Research Articles

Expanding interfacial polymerization for gas separation beyond water purification

Extending interfacial polymerization (IP) to gas separation is challenging due to microdefects in dry conditions, despite its attractive and straightforward processability. This study presents a systematic defect-tailoring approach for highly reproducible polyamide (PA) thin film composite (TFC) membranes with precise size-sieving ability. The approach combines highly porous polyethylene support, extended IP reaction time (60 min), and post-thermal/solvent treatments, resulting in a homogeneous PA selective layer. Particularly, isopropanol treatment removes less-reacted amine-rich monomers/oligomers and promotes PA network chain relaxation, enhancing molecular-sieving capability. The resulting PA TFC membrane exhibits a remarkable H2/CO2 selectivity of 24.8 (±3.1) and an H2 permeance of 13.6 (±1.8) gas permeation unit, surpassing the polymeric upper bound. It also ensures mechanical stability under high feed pressure and resistance to physical aging, highlighting its robustness. Additionally, universality is validated using different amine monomers. This systematic method provides a valuable framework for producing reproducible PA TFC membranes with exceptional gas separation performance, enabling practical implementation across industrial sectors.

One-pot in situ synthesis of ZIF particles to prepare thin-film nanocomposite membranes for CO2 separation

Mixed matrix membranes (MMMs) are more likely to break the Robeson upper bound because they combine the pros of both organic and inorganic membranes. However, in the conventional MMM preparation processes, multi-steps are normally needed and, in many cases, the particle agglomeration and consequent non-selective voids are unavoidable, resulting in poor carbon dioxide (CO2) separation performances. In addition, the agglomeration makes it challenging to fabricate thin-film nanocomposite (TFN) membranes. In this study, zeolitic imidazolate framework (ZIF)-8- and ZIF-67-based TFN membranes were fabricated via a facile one-pot in situ synthesis protocol. The ZIF particles were synthesized in the polymeric solution, then the TFN membranes were fabricated by a dip coating method. With a casting solution concentration of 1.5 wt.%, a selective layer with a thickness of ∼300 nm can be prepared on the porous polyacrylonitrile (PAN) support. The results of thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), Fourier Transform Infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD) showed that ZIFs were successfully synthesized in the casting solution. At 35 °C and 2 bar, the membrane containing 5 wt.% ZIF-67 had a CO2 permeance of 223.35 gas permeation unit (GPU), which was 16.55 % higher than that of pure Pebax.

Wrinkled metal-organic framework thin films with tunable Turing patterns for pliable integration.

Flexible integration spurs diverse applications in metal-organic frameworks (MOFs). However, current configurations suffer from the trade-off between MOF loadings and mechanical compliance. We report a wrinkled configuration of MOF thin films. We established an interfacial synthesis confined and controlled by a polymer topcoat and achieved multiple Turing motifs in the wrinkled thin films. These films have complete MOF surface coverage and exhibit strain tolerance up to 53.2%. The enhanced mechanical properties allow film transfer onto various substrates. We obtained membranes with large H2/CO2 selectivity (41.2) and high H2 permeance (8.46 × 103 gas permeation units), showcasing negligible defects after transfer. We also achieved soft humidity sensors on delicate electrodes by avoiding exposure to harsh MOF synthesis conditions. These results highlight the potential of wrinkled MOF thin films for plug-and-play integration.

Enhanced interaction of CO2 with TCNQ-modified CuO nanoparticle-infused PEO matrix: A novel approach in gas transport technology

We developed a composite membrane based on polyethylene oxide (PEO), achieving high CO2 selectivity, by incorporating 7,7,8,8-tetracyanoquinodimethane (TCNQ)-modified CuO nanoparticles into the PEO matrix. The addition of TCNQ helps in evenly distributing the CuO nanoparticles throughout the membrane, preventing them from clumping together. This treatment not only enhances the dispersion of CuO particles but also imparts a positive charge to their surface, which is beneficial for increasing the selectivity for CO2 over N2. The extent of this surface charge modification on the CuO nanoparticles was evaluated using X-ray photoelectron spectroscopy (XPS), while the synergy between the polymer and the additives was verified through Fourier-transform infrared (FT-IR) spectroscopy studies. The combination of CuO nanoparticles in the membrane contributes to both barrier and carrier effects, enhancing the gas selectivity. This is further aided by the intrinsic properties of PEO, a rubber-like polymer known for its good gas permeance. As a result of these combined effects, the PEO/CuO/TCNQ membrane exhibited a remarkable CO2 selectivity of 393 and a CO2 permeance of 3.9 gas permeation unit (GPU). The superior separation performance of this membrane can be ascribed to three main factors: enhanced solubility due to the oxide layer on the particle surfaces and in the polymer matrix, improved transport efficiency via reversible interactions thanks to the positively charged surface, and the effective barrier provided by the nanoparticles against N2 transport. These findings are expected to contribute significantly to future studies on the surface modification of metal nanoparticles and in the field of gas separation membranes.

Insights into micro-structure and separation mechanism of benzimidazole-linked polymer membrane for H2/CO2 separation

Separation of hydrogen from carbon dioxide for sustainable H2 production and CO2 capture still faces great challenges due to the smaller size of H2 and higher condensability of CO2. Herein, a high-performance benzimidazole-linked polymer (BILP) membrane for hydrogen separation was directly prepared on α-Al2O3 substrate through a facile interfacial polymerization approach at room temperature. The separation performance of the BILP membrane were regulated by controlling the reaction time and the microstructure was systematically characterized. Molecular simulations were performed to deep understand the separation mechanism in the BILP membrane. The best performance membrane displays an extraordinary mixed gas selectivity of 40 for H2/CO2 together with outstanding H2 permeance of 250 gas permeation units (GPU) at 473 K, far exceeding the Robeson’s upper bound. Besides, the membrane can withstand high temperature and pressure, and also shows good H2/N2 and H2/CH4 selectivity. The excellent separation performance, coupled with high temperature and pressure resistance and easy preparation, render BILP membranes great potential for economic H2 purification, H2 recovery, and natural gas treatment.

The effect of different solvents on the formation of large‐area MOF membranes

AbstractMetal–organic framework (MOF) membranes are widely used in gas separation processes. However, the effect of solvents on the formation of large‐area MOF membranes, which directly influences separation performance, has rarely been investigated. In this study, three solvents (methanol, ethanol, and water) were selected to systematically investigate their effects on the zeolite imidazolium frameworks (ZIF) membrane formation via experimental validation and simulations. The results indicated that the solvent selection influenced crystallization rate, crystal size, and ZIF‐8 membrane formation ability. Particularly, when water was used as a solvent, slow nucleation and crystallization of the ZIF‐8 crystals were observed, resulting in a more complete crystal structure and a thinner ZIF‐8 membrane. Therefore, the ZIF‐8 membrane exhibited a gas permeance of 10,000 gas permeation unit and enhanced CO2/N2 selectivity. Furthermore, ZIF‐8 membrane with a surface area of 2400 cm2 and spiral‐wound membrane modules were developed, paving the way for large‐scale industrial production.

Understanding the performance of RHO type zeolite membrane for CH4/N2 separation based on molecular dynamics and deep neural network methods

This study shows a molecular dynamics (MD) simulation study on the performance of the RHO zeolite membrane for separating nitrogen from methane/nitrogen gas mixtures. The contamination of natural gas, predominantly composed of methane, with nitrogen diminishes its value. Zeolite membranes offer promising prospects for gas separation due to their stability, rigid pore structure, and molecular sieving properties. The study investigates the impact of pressure difference (up to 30 MPa), feed composition, and membrane thickness on the separation rate at a system temperature of 298 K. Results demonstrate that the RHO zeolite membrane exhibits high permeability and selectivity for N2 separation, surpassing the upper limit defined by Robson with a maximum permeability of 2.14 × 105 GPU (Gas Permeation Units). Exceptional selectivity of N2 over CH4 molecules is observed. Additionally, altering the feed composition and membrane thickness positively influences the membrane's separation performance, thereby enhancing its efficiency. The findings contribute to the advancement of separation technologies, providing valuable insights into the potential application of zeolite membranes for efficient N2 separation from CH4/N2 gas mixtures in natural gas processing. Furthermore, the study explores the use of Deep Neural Network (DNN) models to predict the membrane's performance under diverse operating conditions. The DNN models, trained using simulation data from MD simulations, exhibit high accuracy with a coefficient of determination (R2) exceeding 0.9, ensuring reliable predictions. The integration of DNN models facilitates the optimization of zeolite membrane-based gas separation systems, improving their design and operation.

Modular Customization and Regulation of Metal-Organic Frameworks for Efficient Membrane Separations.

Metal-organic frameworks (MOFs) are considered ideal membrane candidates for energy-efficient separations. However, the MOF membrane amount to date is only a drop in the bucket compared to the material collections. The fabrication of an arbitrary MOF membrane exhibiting inherent separation capacity of the material remains a long-standing challenge. Herein, we report a MOF modular customization strategy by employing four MOFs with diverse structures and physicochemical properties and achieving innovative defect-free membranes for efficient separation validation. Each membrane fully displays the separation potential according to the MOF pore/channel microenvironment, and consequently, an intriguing H2 /CO2 separation performance sequence is achieved (separation factor of 1656-5.4, H2 permeance of 964-2745 gas permeation unit). Taking advantage of this strategy, separation performance can be manipulated by a non-destructive modification separately towards the MOF module. This work establishes a universal full-chain demonstration for membrane fabrication-separation validation-microstructure modification and opens an avenue for exclusive customization of membranes for important separations.

Metal-Organic Framework Crystal-Glass Composite Membranes with Preferential Permeation of Ethane.

Metal-organic framework (MOF) glass is an easy to process and self-supported amorphous material that is suitable for fabricating gas separation membranes. However, MOF glasses, such as ZIF-62 and ZIF-4 have low porosity, which makes it difficult to obtain membranes with high permeance. Here, a self-supported MOF crystal-glass composite (CGC) membrane was prepared by melt quenching a mixture of ZIF-62 as the membrane matrix and ZIF-8 as the filler. The conversion of ZIF-62 from crystal to glass and the simultaneous partial melting of ZIF-8 facilitated by the melt state of ZIF-62 make the CGC membrane monolithic, eliminating non-selective grain boundaries and improving selectivity. The thickness of CGC membrane can be adjusted to fabricate a membrane without the need of a support substrate. CGC membranes exhibit a C2H6 permeance of 41,569 gas permeation units (GPU) and a C2H6/C2H4 selectivity of 7.16. The CGC membrane has abundant pores from the glassy state of ZIF-62 and the crystalline ZIF-8, which enables high gas permeance. ZIF-8 has preferential adsorption for C2H6 and promotes C2H6 transport in the membrane, and thus the GCG membrane exhibits ultrahigh C2H6 permeance and good C2H6/C2H4 selectivity.

Metal–Organic Framework Crystal–Glass Composite Membranes with Preferential Permeation of Ethane

AbstractMetal–organic framework (MOF) glass is an easy to process and self‐supported amorphous material that is suitable for fabricating gas separation membranes. However, MOF glasses, such as ZIF‐62 and ZIF‐4 have low porosity, which makes it difficult to obtain membranes with high permeance. Here, a self‐supported MOF crystal–glass composite (CGC) membrane was prepared by melt quenching a mixture of ZIF‐62 as the membrane matrix and ZIF‐8 as the filler. The conversion of ZIF‐62 from crystal to glass and the simultaneous partial melting of ZIF‐8 facilitated by the melt state of ZIF‐62 make the CGC membrane monolithic, eliminating non‐selective grain boundaries and improving selectivity. The thickness of CGC membrane can be adjusted to fabricate a membrane without the need of a support substrate. CGC membranes exhibit a C2H6 permeance of 41 569 gas permeation units (GPU) and a C2H6/C2H4 selectivity of 7.16. The CGC membrane has abundant pores from the glassy state of ZIF‐62 and the crystalline ZIF‐8, which enables high gas permeance. ZIF‐8 has preferential adsorption for C2H6 and promotes C2H6 transport in the membrane, and thus the GCG membrane exhibits ultrahigh C2H6 permeance and good C2H6/C2H4 selectivity.

Structure Regulation of MOF Nanosheet Membrane for Accurate H2/CO2 Separation

AbstractHigh‐purity H2 production accompanied with a precise decarbonization opens an avenue to approach a carbon‐neutral society. Metal–organic framework nanosheet membranes provide great opportunities for an accurate and fast H2/CO2 separation, CO2 leakage through the membrane interlayer galleries decided the ultimate separation accuracy. Here we introduce low dose amino side groups into the Zn2(benzimidazolate)4 conformation. Physisorbed CO2 served as interlayer linkers, gently regulated and stabilized the interlayer spacing. These evoked a synergistic effect of CO2 adsorption‐assisted molecular sieving and steric hinderance, whilst exquisitely preserving apertures for high‐speed H2 transport. The optimized amino membranes set a new record for ultrathin nanosheet membranes in H2/CO2 separation (mixture separation factor: 1158, H2 permeance: 1417 gas permeation unit). This strategy provides an effective way to customize ultrathin nanosheet membranes with desirable molecular sieving ability.

Structure Regulation of MOF Nanosheet Membrane for Accurate H2 /CO2 Separation.

High-purity H2 production accompanied with a precise decarbonization opens an avenue to approach a carbon-neutral society. Metal-organic framework nanosheet membranes provide great opportunities for an accurate and fast H2 /CO2 separation, CO2 leakage through the membrane interlayer galleries decided the ultimate separation accuracy. Here we introduce low dose amino side groups into the Zn2 (benzimidazolate)4 conformation. Physisorbed CO2 served as interlayer linkers, gently regulated and stabilized the interlayer spacing. These evoked a synergistic effect of CO2 adsorption-assisted molecular sieving and steric hinderance, whilst exquisitely preserving apertures for high-speed H2 transport. The optimized amino membranes set a new record for ultrathin nanosheet membranes in H2 /CO2 separation (mixture separation factor: 1158, H2 permeance: 1417 gas permeation unit). This strategy provides an effective way to customize ultrathin nanosheet membranes with desirable molecular sieving ability.

Highly selective and permeable SSZ-13 zeolite membranes synthesized by a facile in-situ approach for CO2/CH4 separation

High-quality tubular SSZ-13 zeolite membranes were fabricated by a facile in-situ approach for the first time. The in-situ approach requires only a single hydrothermal step for membrane growth, which is much simpler than the normal multi-step secondary-growth approach with seed preparation and seeding steps. The proper aging time and relatively high synthesis temperature provide sufficient nuclei for SSZ-13 growth, which further facilitates the in-situ formation of continuous membranes on the substrates. Three SSZ-13 zeolite membranes fabricated by the simple in-situ approach displayed ultrahigh average selectivity of (233 ± 46) and high average carbon dioxide permeance of (1220 ± 100) × 10−9 mol (m2 s Pa)−1 [∼3660 ± 300 Gas Permeation Unit (GPU), 1 GPU = 3.348 × 10−10 mol/(m2 s Pa)] at 298 K in the CO2/CH4 (50/50 in mol) mixture. The overall separation performance of the current membranes exceeded that of most reported zeolite membranes in the CO2/CH4 mixture. It indicated that the current in-situ synthesis approach had good reproducibility. The typical membrane also showed excellent separation performance in the CO2/N2 mixture toward the carbon capture from flue gas. The long-term stability of this membrane was investigated in the humidified CO2/CH4 mixture with a relative humidity close to 100%. This simple in-situ approach is suitable to prepare other zeolite membranes for gas separation after improving the gel nucleation.

Zirconia-supported all-silica zeolite CHA membrane with unprecedentedly high selectivity in humidified CO2/CH4 mixture

Continuous and thin all-silica zeolite CHA membranes were prepared successfully on the tubular zirconia/alumina supports by a novel fluoride-free synthesis approach using lithium hydroxide as mineralizer. Membrane synthesis using the uniform and low-viscosity gel displayed good reproductivity. The influences of pressure and temperature on separation data of the membrane in the dry and wet mixtures were comprehensively investigated. The typical membrane had CO2/CH4 and CO2/N2 selectivities of 170 and 33 and carbon dioxide permeances of 950 × 10−9 and 1200 × 10−9 mol/(m2 s Pa) [∼3600 GPU, Gas Permeation Unit: 1GPU = 3.348 × 10−10 mol/(m2 s Pa)] at 298 K in dry CO2/CH4 and CO2/N2 (50/50 in mol) mixtures, respectively. The unprecedentedly high CO2/CH4 selectivity of 430 was obtained for the zeolite membrane at 298 K in wet CO2/CH4 mixture with saturated water vapor. The long-term stability of this membrane was also investigated in humidified mixture with relative humidity of close to 100%. The possible water-gated molecular sieve mechanism in the presence of moisture was proposed.

Fast Blood Oxygenation through Hemocompatible Asymmetric Polymer of Intrinsic Microporosity Membranes.

Membrane technology has attracted considerable attention for chemical and medical applications, among others. Artificial organs play important roles in medical science. A membrane oxygenator, also known as artificial lung, can replenish O2 and remove CO2 of blood to maintain the metabolism of patients with cardiopulmonary failure. However, the membrane, a key component, is subjected to inferior gas transport property, leakage propensity, and insufficient hemocompatibility. In this study, we report efficient blood oxygenation by using an asymmetric nanoporous membrane that is fabricated using the classic nonsolvent-induced phase separation method for polymer of intrinsic microporosity-1. The intrinsic superhydrophobic nanopores and asymmetric configuration endow the membrane with water impermeability and gas ultrapermeability, up to 3,500 and 1,100 gas permeation units for CO2 and O2, respectively. Moreover, the rational hydrophobic-hydrophilic nature, electronegativity, and smoothness of the surface enable the substantially restricted protein adsorption, platelet adhesion and activation, hemolysis, and thrombosis for the membrane. Importantly, during blood oxygenation, the asymmetric nanoporous membrane shows no thrombus formation and plasma leakage and exhibits fast O2 and CO2 transport processes with exchange rates of 20 to 60 and 100 to 350 ml m-2 min-1, respectively, which are 2 to 6 times higher than those of conventional membranes. The concepts reported here offer an alternative route to fabricate high-performance membranes and expand the possibilities of nanoporous materials for membrane-based artificial organs.

Ultra-selective membrane composed of charge-stabilized fixed carrier and amino acid-based ionic liquid mobile carrier for highly efficient carbon capture

Membrane technology has been extensively studied for CO2 capture applications, especially for flue gas sources. In the past decades, facilitated transport membranes (FTMs) have made breakthroughs overcoming the permeance-selectivity trade-off upper bound restricting traditional CO2 separation membranes, but are still facing challenges towards practical applications, including limited performance, such as insufficient CO2/N2 selectivity to achieve 95 % CO2 dry-base purity by one step separation, and long-term stability. Herein, we designed and fabricated a novel FTM structure containing an ionic liquid (1-ethyl-3-methylimidazolium aminoacetate, [Emim][Gly]) as mobile CO2-carrier and a polymeric amine (polyethyleneimine, PEI) as fixed CO2-carrier. The fixed carrier is confined within a carbon nanotube (CNT) framework of 230 nm thickness via electrostatic forces adjusted by a polyelectrolyte (polystyrene sulfonate, PSS), while the mobile carrier diffuses freely within the CNT framework. After optimization of the membrane recipe and spray-coating fabrication procedure, following our previous work, the resulting CNT-PSS-PEI ∼ IL membranes demonstrated an ultra-high CO2/N2 selectivity up to 1,000 with CO2 permeance up to 2,400 GPU (Gas Permeation Unit, 1 GPU = 3.348 × 10−10 mol·s−1·m−2·Pa−1) under vacuum operation condition. Furthermore, one 100-cm2 flat sheet membrane sample was prepared and exhibited one-stage CO2 enrichment from 15 % to 95 % purity (dry-base) for the first time amongst all reported CO2 separation membranes. The membrane retained a stable performance over 50-h operation period under vacuum condition. The extraordinary CO2 separation performance illustrates the great potential of the CNT-PSS-PEI ∼ IL membranes for flue gas carbon capture application.

Size-reduced low-crystallinity ZIF-62 for the preparation of mixed-matrix membranes for CH4/N2 separation

CH4/N2 separation is of great significance for the utilization of unconventional natural gas, however facing great difficulty due to the similarity of physical and chemical properties between components. In this work, a liquid-assisted mechanochemical route was developed for the synthesis of low-crystallinity ZIF-62 with reduced particle size and abundant open metal sites (denoted as ZIF-62-L), and dual-zinc sources (Zn(OH)2 and Zn(OAc)2·2H2O) was found to be crucial for the acquisition of pure phase ZIF-62. The small particle size ensured good compatibility between ZIF-62-L and polymer matrix (polyethyleneimine, PEI), while the abundant open metal sites enhanced the interaction between ZIF-62-L and CH4 molecules. As a result, defect-free ZIF-62-L/PEI mixed-matrix membranes (MMMs) with high filler loadings and largely improved CH4/N2 separation performance were successfully prepared on modified polysulfone (MPSf) ultrafiltration substrate. Specifically, at the ZIF-62-L loading of 50 wt%, the composite membrane exhibit CH4 permeance of 2726.6 gas permeation unit (GPU) and a CH4/N2 selectivity of 3.96, which are 505% and 230% higher than that of the pure PEI/MPSf composite membrane, respectively. These results indicate the great potential of constructing low-crystallinity metal-organic frameworks with increased open metal sites to develop high-performance membranes for CH4/N2 separation.

Enrichment of spent SF6 gas by zeolite membranes for direct reuse in gas-insulated switchgear units

Zeolite membranes have attracted considerable attention in the separation industry owing to their high separation selectivity and permeance. However, their industrial applications have been hindered owing to a lack of case studies focusing on their commercialization. Herein, MFI and SAPO-34 zeolite membranes were employed to purify spent SF6 gas taken from a gas-insulated switchgear (GIS). This study demonstrated that separation by a single zeolite membrane produced ultrapure SF6 gas (>99.7 %) satisfying the reuse guidelines for GIS units. This level of purity is difficult to achieve using polymeric membranes due to the plasticization effect. The synthesized MFI membrane exhibited high N2 permeance with ∼ 2,000 gas permeation units (GPU) at 2 bar and low N2/SF6 selectivity (<50), whereas the SAPO-34 membranes exhibited the opposite trends, i.e., high N2/SF6 selectivity (>500) and relatively low permeance (<600 GPU at 2 bar). Interestingly, the MFI membrane system effectively enriched the SF6 gas, while lower feed pressures achieved by decreasing the feed flows were required for the SAPO-34 membranes to achieve the same purity. Changes in the feed pressure led to corresponding changes in the membrane separation performance, and the concentration polarization increased at high feed pressures. A MFI membrane area of ∼ 0.088 m2 was sufficient to purify the entire spent SF6 gas produced by GIS units at 145 kV in 6 h; this indicates an opportunity to realize compact SF6 enrichment systems. Thus, considering the high separation performance and the small size of the separation system, MFI membranes represent a promising option for the industrial purification of spent SF6 gas from GIS units.

Facile synthesis of porphyrin-based PAF membrane for hydrogen purification

Available online Hydrogen (H2) is a promising clean energy source and its separation and purification from fossil fuels and natural gas is of great significance. Microporous continuous membrane separation is an efficient and energy-saving separation method, in which membranes with a pore size less than 1 nm can better achieve size-dependent sieving of H2. Porous aromatic framework (PAF) continuous membranes are expected to exhibit high-efficiency gas separation due to their highly connected channels as well as structural stability and channel design. Synthesis of continuous PAF membranes using facile methods remains a challenge. Here, we synthesized ultrathin continuous porphyrin-based PAF (ppPAF) membrane using an interfacial polymerization approach. The design introduced rigid porphyrin groups, resulting in a pore size of 0.7 nm for the ppPAF membrane. The ppPAF membrane showed a H2 permeance of 709.2 gas permeation units (GPU), with a H2/CO2 selectivity of 78.8. The ppPAF membrane showed a H2/CH4 selectivity of 93.3, with a H2 permeance of 624.8GPU. Our results provide new ideas for the synthesis of continuous PAF films.

Covalent organic frameworks-incorporated thin film composite membranes prepared by interfacial polymerization for efficient CO2 separation

Thin film composite (TFC) membranes with nanofillers additives for CO2 separation show promising applications in energy and environment-related fields. However, the poor compatibility between nanofillers and polymers in TFC membranes is the main problem. In this work, covalent organic frameworks (COFs, TpPa-1) with rich NH groups were incorporated into polyamide (PA) segment via in situ interfacial polymerization to prepare defect-free TFC membranes for CO2/N2 separation. The formed covalent bonds between TpPa-1 and PA strengthen the interaction between nanofillers and polymers, thereby enhancing compatibility. Besides, the incorporated COFs disturb the rigid structure of the PA layer, and provide fast CO2 transfer channels. The incorporated COFs also increase the content of effective carriers, which enhances the CO2 facilitated transport. Consequently, in CO2/N2 mixed gas separation test, the optimal TFC (TpPa0.025-PIP-TMC/mPSf) membrane exhibits high CO2 permeance of 854 GPU and high CO2/N2 selectivity of 148 at 0.15 MPa, CO2 permeance of 456 GPU (gas permeation unit) and CO2/N2 selectivity of 92 at 0.5 MPa. In addition, the TpPa0.025-PIP-TMC/mPSf membrane also achieves high permselectivty in CO2/CH4 mixed gas separation test. Finally, the optimal TFC membrane showes good stability in the simulated flue gas test, revealing the application potential for CO2 capture from flue gas.