A microporous metal–organic framework with triangular channels for C2H6/C2H4 adsorption separation

Abstract

• Fe 2 BDP 3 exhibits preferential adsorption of C 2 H 6 over C 2 H 4. • C 2 H 6 /C 2 H 4 selectivity of Fe 2 BDP 3 can be as high as 2.1 at ambient condition. • The shape-matching strategy is effective for construction of C 2 H 6 -selective MOFs. For separation of ethylene (C 2 H 4 ) and ethane (C 2 H 6 ), pressure swing adsorption (PSA) with C 2 H 6 -selective porous materials is considered as an ideal alternative to traditional energy-intensity cryogenic distillation. Inspired by the geometry complement feature between molecular lock and target in molecular imprinting recognition system, herein, we select the microporous metal–organic framework Fe 2 (BDP) 3 with triangular channels as study object and investigate its adsorption separation performance for C 2 H 6 /C 2 H 4 . The experiment results indicate that Fe 2 (BDP) 3 exhibits the higher C 2 H 6 uptake than C 2 H 4 and a considerable C 2 H 6 /C 2 H 4 selectivity (2.1). Theoretical calculations reveal the better geometry complementarity between triangle channels and configuration-variable trifurcate C 2 H 6 than rigid plane-like C 2 H 4 play a key role for reversed adsorption relationship. The breakthrough experiments demonstrate the effectiveness of Fe 2 (BDP) 3 for C 2 H 6 /C 2 H 4 adsorption separation under ambient conditions.