Highly Selective Oxygen/Nitrogen Separation Membrane Engineered Using a Porphyrin-Based Oxygen Carrier

Area of Science:

• Materials Science
• Chemical Engineering
• Membrane Technology

Background:

• Air separation is crucial for economic and environmental benefits.
• Facilitated transport membranes offer a promising route for efficient gas separation.

Purpose of the Study:

• To fabricate and characterize defect-free facilitated transport membranes for O2/N2 separation.
• To investigate the effect of tetra(p-methoxylphenyl)porphyrin cobalt chloride (T(p-OCH3)PPCoCl) as a carrier in poly(amide-12-b-ethylene oxide) (Pebax-2533) membranes.

Main Methods:

• Fabrication of thin film composite (TFC) membranes with varying compositions of Pebax-2533 and T(p-OCH3)PPCoCl.
• Characterization of membrane structure and compatibility.
• Evaluation of O2/N2 separation performance, including O2 permeability and selectivity.

Main Results:

• T(p-OCH3)PPCoCl demonstrated good compatibility with Pebax-2533, forming uniform selective layers.
• The addition of T(p-OCH3)PPCoCl significantly improved O2/N2 separation performance.
• At 0.035 MPa, the 0.6 wt% T(p-OCH3)PPCoCl/Pebax-2533 membrane achieved performance exceeding the 2008 Robeson upper bound.

Conclusions:

• The developed TFC membranes are effective for efficient O2/N2 separation.
• These membranes show potential for practical air separation applications under moderate conditions.