Separation of High-Purity C 2 H 2 from Binary C 2 H 2 /CO 2 Using Robust Al-Based MOFs Comprising Nitrogen-Containing Heterocyclic Dicarboxylate

• Published in: ACS applied materials & interfaces 2024-01, Vol.16 (1), p.1342-1350
• Main Authors: Jeong, Se-Min, Kim, Donghyun, Park, Ju Yeon, Yoon, Ji Woong, Lee, Su-Kyung, Lee, Jong Suk, Jo, Donghui, Cho, Kyung Ho, Lee, U-Hwang
• Format: Article
• Language: English
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.3c16849

In this study, three nitrogen-containing aluminum-based metal-organic frameworks (Al-MOFs), namely, CAU-10pydc, MOF-303, and KMF-1, were investigated for the efficient separation of a C H /CO gas mixture. Among these three Al-MOFs, KMF-1 demonstrated the highest selectivity for C H /CO separation (6.31), primarily owing to its superior C H uptake (7.90 mmol g ) and lower CO uptake (2.82 mmol g ) compared to that of the other two Al-MOFs. Dynamic breakthrough experiments, using an equimolar binary C H /CO gas mixture, demonstrated that KMF-1 achieved the highest separation performance. It yielded 3.42 mmol g of high-purity C H (>99.95%) through a straightforward desorption process under He purging at 298 K and 1 bar. To gain insights into the distinctive characteristics of the pore surfaces of structurally similar CAU-10pydc and KMF-1, we conducted computational simulations using canonical Monte Carlo and dispersion-corrected density functional theory methods. These simulations revealed that the secondary amine (C N-H) groups in KMF-1 played a more significant role in differentiating between C H and CO compared to that of the N atoms in CAU-10pydc and MOF-303. Consequently, KMF-1 emerged as a promising adsorbent for the separation of high-purity C H from binary C H /CO gas mixtures.