Ultrafast Semi-Solid Processing of Highly Durable ZIF-8 Membranes for Propylene/Propane Separation

ZIF-8 membranes have emerged as the most promising candidate for propylene/propane (C₃H₆/C₃H₈) separation through its precise molecular sieving characteristics. The poor reproducibility and durability, and high cost, thus far hinder the scalable synthesis and industrial application of ZIF-8 membranes. Herein, we report a semi-solid process featuring ultrafast and high-yield synthesis, and outstanding scalability for reproducible fabrication of ZIF-8 membranes. The membranes show excellent C₃H₆/C₃H₈ separation performance in a wide temperature and pressure range, and remarkable stability over 6 months. The ZIF-8 membrane features dimethylacetamide entrapped ZIF-8 crystals retaining the same diffusion characteristics but offering enhanced adsorptive selectivity for C₃H₆/C₃H₈. The ZIF-8 membrane was prepared on a commercial flat-sheet ceramic substrate. A prototypical plate-and-frame membrane module with an effective membrane area of about 300 cm² was used for efficient C₃H₆/C₃H₈ separation.