The Polymer Built for Pre-Combustion CO₂ Capture
Capturing carbon dioxide efficiently is one of the defining engineering challenges of modern energy systems. From fossil-fueled power plants to hydrogen production units, separating CO₂ from gas streams is becoming increasingly critical.
Traditional approaches, such as amine solvents and cryogenic separation, are effective but come with high energy requirements, large system footprints, and high operational costs.
Membrane-based separation offers a more efficient alternative, using selective polymer films to separate CO₂ under pressure without chemical regeneration.
And in both post-combustion and pre-combustion environments, one material stands out: Celazole® PBI.
Why Carbon Capture Is So Challenging
Separating CO₂ from industrial gas streams is difficult due to temperature, pressure, and chemical complexity.
- High temperatures in syngas streams
- Presence of steam, CO₂, hydrogen, and contaminants
- Pressure conditions exceeding 30 bar
- Need for high selectivity and durability
Traditional systems often require cooling, chemical regeneration, or large-scale infrastructure to operate effectively.
A Material Built for Harsh Conditions
Most polymer membranes struggle under extreme heat and pressure. Materials like PAN, PES, and PSU can compact, degrade, or lose performance.
Celazole® PBI, with a glass transition temperature of 427°C, offers exceptional thermal and chemical stability.
Its fully aromatic structure resists swelling, hydrolysis, and mechanical degradation.
This makes PBI ideal for syngas environments where hydrogen, CO₂, moisture, and acidic gases coexist.
Hydrogen Purification and Pre-Combustion Capture
PBI membranes perform exceptionally in high-temperature, high-pressure hydrogen separation systems.
- Stable at 225°C in steam, hydrogen, and CO₂ environments
- Pressure tolerance up to 200 psig
- Hydrogen recovery >99% with CO₂ rejection above 90%
- Long-term durability with no performance degradation
Unlike traditional membranes, PBI eliminates the need for gas cooling, improving overall process efficiency.
Selectivity Engineered at the Molecular Level
PBI membranes achieve separation through molecular-level selectivity.
Hydrogen molecules permeate quickly, while larger gases like CO₂ and CH₄ are rejected.
- Controlled porosity for optimized separation
- Thermal annealing improves selectivity
- Chemical crosslinking enhances stability and flexibility
Meeting the Challenges of Flue Gas
Post-combustion capture presents different challenges due to low CO₂ concentration and large gas volumes.
PBI-based thin-film composite membranes show strong potential by delivering high permeance while maintaining selectivity.
PBI vs Conventional Gas Separation Membranes
| Property | PBI | PAN / PES | PSU |
|---|---|---|---|
| Thermal Stability | Excellent | Moderate | Moderate |
| Chemical Resistance | High | Moderate | Moderate |
| Pressure Stability | High | Lower | Moderate |
| Best Use Case | High-temp CO₂ capture | Low-temp separation | General membranes |
Raising the Bar in Carbon Capture
Celazole® PBI enables membrane systems that operate reliably in extreme environments where conventional materials fail.
PBI Performance provides high-performance polymer solutions for advanced membrane development in CO₂ capture and gas purification.
Reach out to PBI Performance Products to request a sample or discuss your application.
Frequently Asked Questions
What is pre-combustion CO₂ capture?
It is the process of removing CO₂ from gas streams before combustion, typically during hydrogen production.
Why are membranes used for carbon capture?
Membranes provide energy-efficient separation without chemicals or large equipment.
Why is PBI effective for gas separation?
PBI offers high thermal stability, chemical resistance, and selectivity under extreme conditions.
Can PBI membranes operate at high temperatures?
Yes, PBI membranes perform at temperatures exceeding 200°C with strong durability.