Mixed Matrix Membranes\nBased on MFI Zeolite Nanosheets\nwith Tunable Thickness for CO₂/CH₄ and H₂/CH₄ Separation

Abstract

Mixed matrix membranes (MMMs) combine the advantages\nof polymers\nand nanofillers. In this work, MFI zeolite nanosheets with different\nthicknesses (i.e., 40, 80, and 200 nm) were synthesized hydrothermally.\nMMMs were fabricated by incorporating MFI zeolite nanosheets into\nTröger’s base polymer (TB). Gas separation performance\nof the obtained MMMs was systematically investigated under different\noperation conditions (e.g., feed pressure and test temperature). Meanwhile,\nMMMs were also characterized using various techniques including SEM,\nFTIR, TGA, and XRD. Even though the presence of all three different\nMFI zeolite nanosheets significantly improved the gas permeability.\nIt was found out the MMMs with MFI nanosheets in the lowest thickness\n(i.e., 40 nm) showed the highest improvement in both CO₂ and H₂ permeability (7.2 and 4.9 times, respectively),\ndenoting developing zeolite nanosheet materials with small thickness\ncould be a promising strategy to promote gas separation performances\nof MMMs.