Modified SUZ-4 zeolite with hierarchical stacked structures used as interlayer improving thin-film composite membrane performance for the IPA pervaporation dehydration

Abstract

SUZ-4 zeolite is a needle-like material with an oriented pore structure that has potential for separation. It is desired to prepare high-performance thin film composite (TFC) membranes via the interfacial polymerization (IP) process after incorporating SUZ-4 zeolite interlayers on macroporous ceramic hollow fibers to compensate for the surface defects. However, the incomplete coverage of the needle-like zeolite for the surface seriously affects the performance of the formed membranes. The spatial confinement property of graphene oxide (GO) was used to modify the SUZ-4 zeolite to the SUZ-4(G) zeolite with hierarchical stacked structures and larger size. SUZ-4(G) zeolite achieved sufficient coverage of the alumina substrate and obtained TFC membranes with good performance for isopropanol (IPA) dehydration under the one-pass IP process with ethylenediamine (EDA) and trimesoyl chloride (TMC). The TFC membrane after further optimization displayed a flux of 3.18 ± 0.1 kg/(m2·h) with a separation factor of 3034 ± 98 (the water concentration in permeate was about 99.7 wt%) applied to pervaporation (PV) dehydration of 90 wt% IPA aqueous solution at 60 °C. Additionally, the novel TFC membrane developed has the potential for further applications due to its good stability.