Novel ZIF-300 Mixed-Matrix Membranes for Efficient CO₂ Capture

Area of Science:

• Materials Science
• Chemical Engineering
• Membrane Technology

Background:

• Mixed-matrix membranes (MMMs) offer high separation performance.
• Metal-organic frameworks (MOFs) are promising components for MMMs.
• Zeolite imidazolate framework (ZIF-300) and polyether block amide (PEBA) are key materials.

Purpose of the Study:

• To develop a novel ZIF-300/PEBA MMM for enhanced CO2 capture.
• To optimize ZIF-300 crystal size for improved membrane performance.
• To evaluate the CO2/N2 separation capabilities of the developed MMM.

Main Methods:

• Optimizing hydrothermal synthesis to reduce ZIF-300 crystal size to ~1 μm.
• Fabricating ZIF-300/PEBA MMMs with varying ZIF-300 loadings.
• Characterizing membrane morphology, physicochemical properties, and sorption behavior.
• Measuring CO2 permeability and CO2/N2 selectivity.

Main Results:

• Reduced ZIF-300 crystal size (~1 μm) maintained preferential CO2 sorption without structural degradation.
• Uniformly incorporated ZIF-300 crystals significantly enhanced CO2 permeability and CO2/N2 selectivity in PEBA membranes.
• Optimized MMMs (30 wt% ZIF-300) achieved 83 Barrer CO2 permeability and 84 CO2/N2 selectivity.
• Performance exceeded the upper bound of state-of-the-art membranes for CO2/N2 separation.

Conclusions:

• The novel ZIF-300/PEBA MMM demonstrates superior CO2/N2 separation performance.
• Optimized ZIF-300 crystal size and loading are crucial for high membrane efficiency.
• This ZIF-300/PEBA MMM is a promising candidate for efficient CO2 capture processes.