C₂H₂/CO₂ Separation by a Carborane Hybrid 2D Metal-Organic Framework

Area of Science:

• Materials Science
• Chemical Engineering
• Nanotechnology

Background:

• Separating acetylene (C2H2) from carbon dioxide (CO2) is industrially crucial but difficult due to similar physical properties.
• Developing advanced materials for selective gas adsorption remains a key challenge.

Purpose of the Study:

• To synthesize and characterize a novel boron-rich 2D metal-organic framework, ZNU-14, for acetylene/carbon dioxide separation.
• To evaluate the gas adsorption properties and separation performance of ZNU-14.

Main Methods:

• Supramolecular assembly of Zn2+, p-C2B10H10-(COOH)2, and di(pyridin-4-yl)amine to form ZNU-14.
• Gas adsorption isotherm measurements and breakthrough experiments.
• Ideal Adsorbed Solution Theory (IAST) calculations and theoretical binding studies.

Main Results:

• ZNU-14 possesses a 1D channel (7.6 × 12.5 Å2) with an electronegative pore surface.
• Exhibits high C2H2 adsorption capacity (43.6 cm3 g-1) and selectivity (IAST: 6.3-9.7) over CO2.
• Demonstrates excellent dynamic selectivity and recyclability in practical breakthrough separation experiments.

Conclusions:

• ZNU-14 is a promising material for efficient acetylene/carbon dioxide separation.
• Its moderate adsorption heat facilitates easy regeneration.
• The material shows strong potential for industrial gas separation applications.