Immobilization of Amino‐site into a Pore‐Partitioned Metal–Organic Framework for Highly Efficient Separation of Propyne/Propylene

Abstract

AbstractAdsorptive separation of propyne/propylene (C3H4/C3H6) is a crucial yet complex process, however, it remains a great difficulty in developing porous materials that can meet the requirements for practical applications, particularly with an exceptional ability to bind and store trace amounts of C3H4. Functionalization of pore‐partitioned metal–organic frameworks (ppMOFs) is methodically suited for this challenge owing to the possibility of dramatically increasing binding sites on highly porous and confined domains. We here immobilized Lewis‐basic (−NH2) and Lewis‐acidic (−NO2) sites on this platform. Along with an integrated nature of high uptake of C3H4 at 1 kPa, high uptake difference of C3H4−C3H6, moderated binding strength, promoted kinetic selectivity, trapping effect and high stability, the NH2‐decorated ppMOF (NTU‐100‐NH2) can efficiently produce polymer‐grade C3H6 (99.95 %, 8.3 mmol ⋅ g−1) at room temperature, which is six times more than the NO2‐decorated crystal (NTU‐100‐NO2). The in situ infrared spectroscopy, crystallographic analysis, and sequential blowing tests showed that the densely packed amino group in this highly porous system has a unique ability to recognize and stabilize C3H4 molecules. Moving forward, the strategy of organic functionalization can be extended to other porous systems, making it a powerful tool to customize advanced materials for challenging tasks.