Ultra-High Purity and Productivity Separation of CO₂ and C₂H₂ from CH₄ in Rigid Layered Ultramicroporous Material

Area of Science:

• Materials Science
• Chemical Engineering
• Adsorption Science

Background:

• Efficient gas separation is crucial for natural gas purification and chemical production.
• Current adsorbents face challenges in achieving high selectivity, uptake, and diffusion rates simultaneously.
• Developing advanced materials for selective gas adsorption remains a key research area.

Purpose of the Study:

• To report a novel 2D layered ultramicroporous framework (ZUL-100) for gas separation.
• To demonstrate the material's capability for high-purity carbon dioxide and acetylene production.
• To investigate the underlying mechanisms for the observed separation performance.

Main Methods:

• Synthesis and characterization of the ZUL-100 framework.
• Gas adsorption isotherms and kinetic uptake measurements.
• In situ FTIR, single-crystal XRD, and DFT-D modeling for mechanism elucidation.

Main Results:

• ZUL-100 exhibits record IAST selectivities for CO2/CH4 (3.2 × 10^5) and C2H2/CH4 (1.7 × 10^10).
• Achieved record uptakes for CO2 (3.10 mmol/g) and C2H2 (4.79 mmol/g).
• High-purity gas separation (≥99.999% CH4, CO2, C2H2) in a single adsorption-desorption cycle.

Conclusions:

• The synergistic ligand/anion binding and multiple diffusion pathways in ZUL-100 enable superior gas separation.
• ZUL-100 offers a promising solution for efficient natural gas purification and acetylene production.
• The material demonstrates high productivity and yield in separating target gases.