Related Experiment Video
Updated: Jul 1, 2025
07:45
Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes
Published on: August 16, 2018
10.0K
Unexpectedly High Propylene/Propane Separation Performance of Asymmetric Mixed-Matrix Membranes through
Yinying Hua, Amro M O Mohamed1, Gyeong Min Choi2
1Chemical Engineering Program, Texas A&M University at Qatar, PO Box 23874, Doha 23874, Qatar.
ACS Applied Materials & Interfaces
|March 14, 2024
Summary
This study introduces additives to enhance zeolitic-imidazolate framework-8 (ZIF-8) mixed-matrix membranes (MMMs) for superior propylene/propane separation. Sodium formate additive significantly boosts selectivity, achieving a record separation factor for ZIF-8 MMMs.
Area of Science:
- Materials Science
- Chemical Engineering
- Separation Technology
Background:
- Zeolitic-imidazolate framework-8 (ZIF-8) is a key filler for selective mixed-matrix membranes (MMMs) in gas separations.
- Existing MMM fabrication methods face challenges in scalability and performance optimization.
- The PIMOF (phase-inversion in sync with in situ MOF formation) approach offers a scalable route for MMM fabrication.
Purpose of the Study:
- To investigate the impact of additives (sodium formate, 1,4-butanediol) on ZIF-8 formation within polymer matrices.
- To enhance the separation performance of asymmetric MMMs produced via the PIMOF method.
- To correlate computational findings on ZIF-8 nanoparticle size with experimental separation results.
Main Methods:
- Fabrication of mixed-matrix membranes (MMMs) using the PIMOF approach.
- Inclusion of sodium formate and 1,4-butanediol as additives in the coagulation bath.
- Experimental characterization of gas separation performance (propylene/propane).
- Computational modeling to study ZIF-8 nanoparticle size effects on interaction energy and aperture.
Main Results:
- MMMs with sodium formate additive achieved a C3H6/C3H8 separation factor of 222.5 ± 1.8, a significant improvement over non-additive MMMs (57.7 ± 11.2).
- The enhanced performance is attributed to the formation of extremely small, amorphous or poorly crystalline ZIF-8-like particles.
- Computational results confirmed that smaller ZIF-8 nanoparticles lead to stronger polymer-ZIF interactions, reducing effective aperture size and enhancing selectivity.
Conclusions:
- Sodium formate additive dramatically improves the propylene/propane separation performance of PIMOF-fabricated MMMs.
- The study demonstrates a novel method for optimizing ZIF-8 MMMs through controlled filler formation.
- The achieved separation performance surpasses previously reported ZIF-8 MMMs and polycrystalline ZIF-8 membranes.
