Rapid microwave-assisted seeding and secondary growth synthesis of ZIF-8 membrane for propylene/propane separation

Abstract

Owing to their permanent porosity, diverse topology structures, and coordination factors combined with chemical tunability, the zeolitic imidazolate framework (ZIF) has shown great potential for the effective separation of hydrocarbon mixtures. In this work, the authors presented a simple microwave-assisted seeding strategy to rapidly prepare a seed layer for the synthesis of high-quality ZIF-8 membranes for propylene/propane separation. The resulted membranes grown on planar alumina support displayed excellent separation performances for a wide range of propylene/propane mixtures. The membrane displayed a propylene/propane separation factor of 70 and propylene permeance of 105×10-10 mol.m-2s-1Pa-1. Long-term stability test also showed stable gas permeance and separation performance of the ZIF-8 membranes in both atmospheric conditions and propylene/propane mixture stream.