A new TIFSIX anion pillared metal organic framework with abundant electronegative sites for efficient C₂H₂/CO₂separation

Abstract

Separation of acetylene (C2H2) from carbon dioxide (CO2) is important in industry to produce high purity C2H2 but challenged by the close physical properties. Herein, a novel microporous TIFSIX anion...

An ultramicroporous multi-walled metal–organic framework for efficient C2H2/CO2 separation under humid conditions

“…With the increase in uptake, the Q st of both of them decreased rst and then increased. The Q st value of C 2 H 2 is comparable to or much higher than that of many reported MOFs, such as SNNU-45 (39.9 kJ mol −1 ), 36 NUM-15 (37.4 kJ mol −1 ), 49 JCM-1 (36.9 kJ mol −1 ), 50 ZNU-7 (35.3 kJ mol −1 ), 43 DZU-1 (31.7 kJ mol −1 ), 44 UTSA-74 (31 kJ mol −1 ), 38 BSF-1 (30.7 kJ mol −1 ), 48 UTSA-220 (29 kJ mol −1 ), 46 CuZn 3 (PDDA) 3 (OH) (28.9 kJ mol −1 ), 51 etc. (Table S1 †).…”

“…2d, the selectivity of equimolar C 2 H 2 /CO 2 was calculated to be 13.6 to 11.8 under 0–1 bar. The IAST selectivity of In-TATB at 298 K and 1 bar (11.8) is superior to those of many well-performing materials such as UTSA-74 (9), 38 ZNU-7 (6.7), 43 DZU-1 (6.1), 44 TCuI (5.3), 45 SNNU-45 (4.5), 36 UTSA-220 (4.4), 46 FJU-90 (4.3), 37 JNU-1 (6.6), 47 BSF-1 (3.4), 48 NUM-15 (2.8) 49 and some other benchmark materials shown in Table S1† and Fig. 2f.…”

“…The breakthrough interval for In-TATB (7.3 and 16.9 min g −1 ) can be comparable to those of other MOF materials with good performance in C 2 H 2 /CO 2 separation under similar conditions. 43,49,52 Strikingly, the breakthrough curve for CO 2 exhibited a typical but strong rolling-up at the breakthrough point, with a C/C 0 value beyond 1.0, indicating that some of the CO 2 was desorbed and replaced by C 2 H 2 until breakthrough equilibrium, which can be attributed to their large affinity difference. 53 As shown in Fig.…”

A microporous bismuth-based MOF for efficient separation of acetylene from carbon dioxide

“…In dynamic breakthrough testing with the binary mixture, CO 2 was detected first at the outlet of the column; breakthrough occurred first at the initial stage and later a high pure grade was achieved without detectable C 2 H 2 , then after a period C 2 H 2 was detected. The C 2 H 2 /CO 2 separation performance is higher than or comparable to that of MUF-17, 48 ZNU-7, 56 or FJU-6–TATB, 57 while it is lower than that of CAU-10–H 52 or JXNU-12 (F). 58 To further achieve the target of practical applications, we also investigated the C 2 H 2 /CO 2 separation performance with a different gas flow rate (2.0 mL min −1 ).…”

Metal–Organic Framework with Space-Partition Pores by Fluorinated Anions for Benchmark C2H2/CO2 Separation

“…To resolve this trade-off predicament, one may either enhance the C 2 H 2 uptake in narrow-pore MOFs or improve the selectivity in moderate-pore MOFs. Extensive previous works demonstrate that anion hybrid MOFs (e.g., SIFSIX family, ZNU-1) commonly exhibit a high C 2 H 2 /CO 2 selectivity owing to their specific anionic binding sites and ultramicropores. − However, the exclusive presence of ultramicropores results in inadequate pore volumes for C 2 H 2 accommodation, leading to a low C 2 H 2 storage capacity in general. In this context, we hypothesized that the use of fluorinated anions as pore space partitioning agents could separate the large-volume pores in MOFs into ultramicropores (<7 Å) and micropores (7–20 Å), potentially enhancing the discriminative adsorption of C 2 H 2 relative to CO 2 without diminishing the considerable C 2 H 2 uptake capacity (Scheme c).…”