Synthesis of high-performance zeolite t membrane in fluoride media

Oriented zeolite T membranes with high pervaporation performance were synthesized on seeded porous mullite supports in fluoride media. Zeolite powders and membranes were characterized by means of XRD, SEM and MAS NMR. The influences of synthesis conditions such as additive, n_NaF/n_KF ratio, synthesis temperature and time on membrane growth and separation properties were investigated. Fast crystallization mechanism of zeolite T layers in fluoride media was also suggested. The addition of alkali metal fluorides promoted the crystallization of supported zeolite T layers and affected the morphology of crystals. Fluoride-derived zeolite T membranes under optimized synthesis conditions had an average flux of (4.91 ±0.18) kg · m⁻² · h⁻¹ and an average separation factor of 7 060±1 130 for a 10:90 (w/w) of water/i-propanol mixture at 348 K.