Mixed Matrix Membranes Based on Nanoparticle, Nanorod, and Nanosheet MFI-Type Zeolites for Gas Separation

Membranes have been considered as promising alternatives for natural gas sweetening. Mixed matrix membranes (MMMs) possess superior gas separation performance and the potential to combine varieties of polymers and filler materials. In the current work, MMMs have been fabricated via employing Tröger's base (TB) polymer and zeolites with three different morphologies. Simultaneously, CO2/CH4 and H2/CH4 separation performances of the obtained MMMs were comprehensively investigated. It is found out that the presence of the MFI-type zeolites significantly improved the gas permeability, but the selectivity was somehow reduced. Among the three different nanofillers, nanosheet zeolite-based MMMs presented the highest gas permeability; with 20 wt % nanosheet zeolites, both CO2 and H2 permeabilities were increased to 348.6 and 441.5 Barrer, which were improved by 522.0 and 256.2%, respectively. In addition, SEM, XRD, FTIR, and TGA were also employed to characterize the obtained MMMs.