Achieving Record C₂H₂ Packing Density for Highly Efficient C₂H₂/C₂H₄ Separation with a Metal-Organic Framework...

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Science

Background:

• Adsorptive separation of acetylene (C2H2) from ethylene (C2H4) is crucial for purifying ethylene.
• Metal-organic frameworks (MOFs) show promise for C2H2/C2H4 separation, but require optimized performance and scalable, green production.

Purpose of the Study:

• To report an efficient MOF, Cu(OH)INA, for C2H2/C2H4 separation.
• To investigate the separation mechanism and develop a scalable, green synthesis protocol.
• To assess the material's regeneration and long-term stability.

Main Methods:

• Synthesis of Cu(OH)INA MOF.
• Acetylene/ethylene separation performance testing.
• Density Functional Theory (DFT) calculations for mechanism elucidation.
• Evaluation of regeneration and stability under various conditions.

Main Results:

• Cu(OH)INA achieved a record C2H2 packing density of 351 mg/cm³ at 0.01 bar.
• DFT revealed a synergistic binding mechanism involving pore confinement and oxygen sites.
• A scalable, green synthesis protocol yielded a space-time yield of 544 kg/m³ day⁻¹.
• The material exhibited a low heat of adsorption (~36 kJ/mol) and stable performance over multiple cycles, even after exposure to water or air.

Conclusions:

• Cu(OH)INA is a highly effective MOF for C2H2/C2H4 separation.
• The material's properties are beneficial for regeneration and thermal management.
• The developed synthesis protocol is scalable and environmentally friendly.
• Cu(OH)INA demonstrates robust and enduring separation performance for practical applications.