Wet flue gas CO₂ capture and utilization using one-dimensional metal-organic chains

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Metal-organic frameworks (MOFs) offer tunable porosity for gas adsorption.
• Selective carbon dioxide (CO2) capture from industrial flue gas is crucial for mitigating climate change.
• Efficient conversion of CO2 into value-added products is a key goal in sustainable chemistry.

Purpose of the Study:

• To synthesize and characterize a novel ultramicroporous MOF for selective CO2 capture.
• To investigate the MOF's capacity for CO2 conversion into cyclic carbonates.
• To evaluate the MOF's performance in the presence of water and nitrogen.

Main Methods:

• Synthesis of a Ni(II)-based MOF with pyrazole dicarboxylate and adenine ligands.
• Characterization using UV/vis spectroscopy, nitrogen adsorption isotherms, and CO2 isotherms.
• Breakthrough experiments for CO2 capture from dry and wet flue gas.
• Catalytic evaluation for CO2 fixation into epoxides.

Main Results:

• The synthesized MOF exhibits ultramicroporous structure with a pore volume of 0.130 cm3 g-1.
• High CO2 affinity (35.5–41.9 kJ mol-1) and CO2/N2 selectivity (28.5–31.5) were observed.
• Effective CO2 capture from both dry (1.48 mmol g-1) and wet (1.14 mmol g-1) flue gas was achieved.
• The MOF demonstrated catalytic activity for cyclic carbonate formation with a turnover frequency of 21.95 h-1.

Conclusions:

• The novel MOF is effective for selective CO2 capture from flue gas, even in the presence of water.
• The material can be regenerated and reused multiple times with consistent performance.
• The MOF serves as a bifunctional material for both CO2 capture and catalytic conversion into valuable products.