Cage-based metal-organic framework with two-fold interpenetration for Propyne/propylene adsorptive separation

A two-fold interpenetrated cage-based Fe 2 Co-MOF was synthesized. • Fe 2 Co-MOF exhibits permanent microporosity with cage-confined cavities. • Fe 2 Co-MOF exhibits high C 3 H 4 uptake and moderate C 3 H 4 /C 3 H 6 selectivity. • GCMC simulations reveal that cage-confined cavities and multiple weak host-guest interactions account for the preferential adsorption of C 3 H 4 . The removal of propyne (C 3 H 4 ) from propylene (C 3 H 6 ) is essential for polymer-grade C 3 H 6 but remains challenging due to their similar physicochemical properties. Herein, we report a cage-based metal-organic framework, [Fe 2 Co(μ 3 -O)(BTB) 4/3 (BPDC)(H 2 O) 3 ] n (Fe 2 Co-MOF), featuring a two-fold interpenetrated framework and permanent porosity for preferential C 3 H 4 over C 3 H 6 . At 298 K, Fe 2 Co-MOF exhibits a higher uptake of C 3 H 4 than C 3 H 6 , reaching 91.5 cm 3  g −1 at 0.1 bar and 207.4 cm 3  g −1 at 1 bar. Experimental results and GCMC simulations indicate stronger host-guest interactions with C 3 H 4 , highlighting Fe 2 Co-MOF as a promising adsorbent for preferential adsorption of C 3 H 4 over C 3 H 6 . A two-fold interpenetrated cage-based Fe 2 Co-MOF with permanent microporosity and cage-confined pores exhibits high C 3 H 4 uptake and moderate C 3 H 4 /C 3 H 6 selectivity. GCMC simulations reveal that cage-confined cavities and multiple weak host-guest interactions account for the preferential adsorption of C 3 H 4 . Download: Download high-res image (92KB) Download: Download full-size image