One-Dimensional Channel with Side Pockets for Rapid Diffusion and Efficient C₂H₂ Purification.

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Science

Background:

• Separating acetylene (C₂H₂) from carbon dioxide (CO₂) is difficult due to similar molecular properties.
• Existing separation methods often face challenges with efficiency and energy consumption.

Purpose of the Study:

• To design and synthesize novel metal-organic frameworks (MOFs) for selective acetylene capture.
• To investigate the performance of these MOFs in separating acetylene from carbon dioxide mixtures.

Main Methods:

• Synthesis of a series of isostructural pillar-layered MOFs (JNU-13, JNU-13-CH₃, JNU-13-(CH₃)₂).
• Characterization of MOF structures and pore environments.
• Gas adsorption and breakthrough experiments to evaluate separation performance.

Main Results:

• JNU-13-CH₃ exhibits a high C₂H₂ packing density (360 g L^-1) and low adsorption enthalpy (31.61 kJ mol^-1).
• Achieved high C₂H₂ capture capacity (3.46 mmol g^-1) from C₂H₂/CO₂ mixtures, even under humid conditions.
• Demonstrated scale-up synthesis and collection of high-purity acetylene (>99.9%).

Conclusions:

• The developed MOFs, particularly JNU-13-CH₃, show excellent potential for energy-efficient acetylene purification.
• The unique pore structure with orthogonal side pockets effectively balances dense packing and rapid mass transport.
• This strategy offers a promising approach for industrial-scale gas separation challenges.