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Updated: Jul 25, 2025
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A Uniaxial Compression Experiment with CO2-Bearing Coal Using a Visualized and Constant-Volume Gas-Solid Coupling Test System
Published on: June 12, 2019
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Relationship between Permeability and Structure of CO2-Assisted Polymer Compression Products.
1Research Institute for Chemical Process Technology, National Institute of Advanced Industrial Science and Technology, 4-2-1 Nigatake, Miyagino-ku, Sendai 983-8551, Japan.
Membranes
|June 27, 2023
Summary
This study developed new membrane filters using a CO2-assisted polymer compression method. The filters demonstrated high open-pore ratios, making them suitable for various filtration applications.
Area of Science:
- Materials Science
- Chemical Engineering
Background:
- Membrane filters are crucial in various industrial and scientific applications.
- Optimizing filter performance requires understanding pore structure and fluid dynamics.
Purpose of the Study:
- To fabricate membrane filters using a novel CO2-assisted polymer compression method.
- To characterize the structural properties and liquid permeability of the fabricated filters.
Main Methods:
- Polyethylene terephthalate nonwoven fabrics were used to create filters via CO2-assisted polymer compression.
- Liquid permeability tests and X-ray computed tomography were employed for structural analysis.
- Tortuosity, pore size distribution, and open pore percentage were evaluated.
Main Results:
- Filter tortuosity was found to correlate with porosity.
- Pore size estimations from permeability tests and X-ray computed tomography showed good agreement.
- A high open-pore ratio (98.5%) was achieved even at a porosity of 0.21.
Conclusions:
- The CO2-assisted polymer compression method is effective for producing high-performance porous filter materials.
- The high open-pore ratio achieved is advantageous for fluid flow in filter applications.
- The developed filters show promise for effective filtration processes.
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