Thiadiazole-Functionalized Th/Zr-UiO-66 for Efficient C₂H₂/CO₂ Separation

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Science

Background:

• Adsorptive separation is crucial for purifying gases with similar properties, like acetylene from carbon dioxide.
• Metal-organic frameworks (MOFs) offer tunable properties ideal for designing advanced adsorbents.
• Separating acetylene (C2H2) from carbon dioxide (CO2) presents a significant challenge due to their similar physicochemical properties.

Purpose of the Study:

• To develop a highly efficient adsorbent for acetylene (C2H2) and carbon dioxide (CO2) separation.
• To fine-tune the pore environment of Zr- and Th-based UiO-66 MOFs using isoreticular functionalization.
• To investigate the impact of ligand functionalization on adsorbent performance for challenging gas separations.

Main Methods:

• Employed an isoreticular functionalization strategy to immobilize benzothiadiazole groups onto Zr- and Th-based UiO-66 via bottom-up synthesis.
• Synthesized and characterized the functionalized adsorbent, designated UPC-120.
• Evaluated C2H2/CO2 separation performance using adsorption isotherms, dynamic breakthrough experiments, and theoretical simulations.

Main Results:

• The functionalized UPC-120 adsorbent demonstrated enhanced C2H2/CO2 separation performance compared to unmodified counterparts.
• Adsorption isotherms and breakthrough curves confirmed the superior separation capabilities of UPC-120.
• Theoretical simulations provided insights into the mechanisms underlying the enhanced separation.

Conclusions:

• Ligand functionalization of MOFs, guided by isoreticular chemistry, is an effective strategy for improving challenging gas separations.
• The developed UPC-120 adsorbent shows promise for efficient acetylene purification from carbon dioxide.
• This approach offers a new perspective for designing advanced adsorbents for industrial gas separation processes.