Construction of indium–organic frameworks with flu-topology for efficient acetylene separation

Abstract

Development of efficient acetylene (C₂H₂) adsorbents is extremely important for industrial gas purification. In this study, a novel indium–organic framework (In–MOF) with flu-topology was constructed for efficient C₂H₂ separation from gas mixtures. Structural characterization revealed a high specific surface area of 749.9 m² g⁻¹ and a uniform pore size of 6.1 Å of the obtained SNNU-400. Stability studies suggested that SNNU-400 exhibited excellent chemical stability over a wide pH range of 2–11 and superior thermal stability up to 400 °C. Gas adsorption studies at 298 K and 1 atm revealed excellent adsorption capacity for C₂H₂ (105.6 cm³ g⁻¹) compared to CO₂ (61.4 cm³ g⁻¹) and C₂H₄ (74.6 cm³ g⁻¹). Benefitting from the relatively strong C–H_C2H2⋯π_PTO, SNNU-400 showed promising separation potential for equimolar C₂H₂/CO₂ and C₂H₂/C₂H₄ mixtures, as evidenced by high selectivity values (7.4 for C₂H₂/CO₂ and 5.1 for C₂H₂/C₂H₄). This study offers a promising solution for practical industrial applications in the field of clean energy and sustainable chemistry.