Mixed Matrix Membranes for C₂H₄/C₂H₆ Separation Using a Phosphate Anion-Pillared Microporous Material

Abstract

The development of efficient membranes for ethylene/ethane (C 2 H 4 /C 2 H 6 ) separation is highly important. Here, we report the development of a series of new mixed matrix membranes (ZnAtzPO 4 /6FDA-DAM MMMs) based on a microporous material with phosphate anion pillar ZnAtzPO 4 (Atz = 3-amino-1, 2, 4-triazole) and 6FDA-DAM polymer matrix. Compared with the pure 6FDA-DAM membranes, the C 2 H 4 permeability and the C 2 H 4 /C 2 H 6 selectivity of 10 wt % ZnAtzPO 4 /6FDA-DAM MMMs were simultaneously increased by 46 and 6%, breaking the trade-off between permeability and selectivity. Interestingly, the separation performance of ZnAtzPO 4 /6FDA-DAM MMMs at 10 wt % for the equimolar C 2 H 4 /C 2 H 6 gas mixture was 105.0 Barrer and 3.90, which surpassed the 2013 upper bound of C 2 H 4 /C 2 H 6 . For ZnAtzPO 4 /6FDA-DAM MMMs with 10 wt % filler loading, both the solubility selectivity and the diffusion selectivity continued to rise concurrently, enhancing the C 2 H 4 /C 2 H 6 separation performance of ZnAtzPO 4 /6FDA-DAM MMMs. This work generates a useful concept for the design and fabrication of highperformance MMMs.