Optimization of functional groups in CAU-10(Al) for enhanced acetylene (C₂H₂) storage and effective C₂H₂/CO₂ separation

Title : Optimization of functional groups in CAU-10(Al) for enhanced acetylene (C₂H₂) storage and effective C₂H₂/CO₂ separation

Abstract:

The adsorptive separation of acetylene (C₂H₂) from C₂H₂/CO₂ mixtures has emerged as a promising alternative to cryogenic distillation, enabling the production of high-purity C₂H₂ via safer and more energy-efficient processes. Aluminum-based metal-organic frameworks (MOFs), including MIL-160 and CAU-10-NH₂, have demonstrated exceptional acetylene adsorption capacities, exhibiting high selectivity and acetylene packing densities. Recent studies indicate that incorporating heteroatoms into the pore walls of MOFs can significantly enhance C₂H₂ capture performance. However, a systematic and comparative investigation regarding the influence of various functional groups within an identical MOF structure on their C₂H₂ sorption behavior remains lacking. In the present work, a series of CAU-10 derivatives were synthesized utilizing Al(III) metal centers and a range of functionalized organic linkers, including unmodified terephthalate (-H) and its substituted analogues (-OH, -F, -NO₂, -NH₂, and -CH₃), to probe their C₂H₂ and CO₂ adsorption characteristics systematically. The C₂H₂/CO₂ separation efficacy was evaluated through single-component adsorption isotherms, ideal adsorbed solution theory (IAST) calculations, and dynamic breakthrough experiments under both dry and humid conditions. Remarkably, CAU-10-CH3 exhibited a record acetylene packing density of 543 g L?¹ at 25?°C, which is 2.8-fold higher than the corresponding CO₂ uptake at 1 bar. Comparative dynamic breakthrough experiments involving CAU-10-CH₃ and CAU-10-NH₂ further validated CAU-10-CH₃ as a leading candidate for selective acetylene adsorption under variable humidity conditions^1.

Biography:

Maftun Salimov is currently pursuing a PhD in the Department of Advanced Materials and Chemical Engineering at Korea National University of Science and Technology. His research focuses on the development and characterization of metal–organic frameworks (MOFs) for the selective separation and purification of C2 hydrocarbons. He is working under the guidance of Dr. U-Hwang Lee and Dr. Su-Kyung Lee, our group investigates novel and efficient synthetic methodologies, elucidates the structure–property relationships of porous materials, and explores their potential applications in gas storage and separation. His particular emphasis is placed on optimizing pore architecture—specifically, aperture size and the incorporation of functional groups—to enhance adsorption selectivity.