Fine‐Tuned Ultra‐Microporous Metal–Organic Framework in Mixed‐Matrix Membrane: Pore‐Tailoring Optimization for C2H2/C2H4 Separation. Issue 13 (19th February 2023)

• Record Type: Journal Article
• Authors: Xu, Tong; Zhang, Panpan; Cui, Fengchao; Li, Jiantang; Kan, Liang; Tang, Baobing; Zou, Xiaoqin; Liu, Yunling; Zhu, Guangshan
• Is Part Of: Advanced materials. Volume 35:Issue 13(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-02-19
• Subjects: C 2H 2 separation -- mixed‐matrix membranes -- reticular chemistry -- ultra‐microporous MOFs; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202204553
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Effective separation of ethyne from ethyne/ethylene (C2 H2 /C2 H4 ) mixtures is a challenging and crucial industrial process. Herein, an ultra‐microporous metal–organic framework (MOF) platform, Cd(dicarboxylate)2 (ditriazole), with triangular channels is proposed for high‐efficiency separation of C2 H2 from C2 H4 . The targeted structures are constructed via a mixed‐ligand strategy by selecting different‐sized ligands, allowing for tunable pore sizes and volumes. The pore properties can be further optimized by additional modification via pore environment tailoring. This concept leads to the successful synthesis of three ultra‐microporous Cd‐MOFs (JLU‐MOF87–89). As intended, C2 H2 uptake and C2 H2 /C2 H4 selectivity gradually increase with progressively optimizing the pore structure by adjusting ligand length and substituents. JLU‐MOF89, functionalized with methyl groups, features the most optimal pore chemistry and shows selective recognition of C2 H2 over C2 H4, owing to the framework–C2 H2 host–guest interactions. Furthermore, JLU‐MOFs are fabricated into mixed‐matrix membranes for C2 H2 /C2 H4 separation. C2 H2 permeability and C2 H2 /C2 H4 permselectivity are substantially enhanced by ≥400% and ≥200%, respectively, after hybridization of JLU‐MOF88 and JLU‐MOF89 with a polyimide polymer (6FDA–ODA). These membranes can work efficiently and are stable under different conditions, demonstrating their potential in actual ethyne separation. Abstract : A series of ultra‐microporous metal–organic frameworks (MOFs) (JLU‐MOF87–89) with triangular channels is successfully blueprinted and constructed via mixed‐ligand strategy. By selecting different‐sized ligands and applying linker modification, the channel is fine‐tuned and precisely tailored into the optimized zone, realizing high C2 H2 /C2 H4 selectivity. Moreover, the excellent performances of JLU‐MOF mixed‐matrix membranes have validated the application potential for C2 H2 /C2 H4 separation.