Continuous and high silica SSZ-13 zeolite membranes were prepared on porous mullite supports from high SiO2/Al2O3 ratio or aluminum-free precursor synthesis gel. Single gas permeance (CO2 and CH4) of the high silica SSZ-13 zeolite membrane was decreased with the SiO2/Al2O3 ratio in the precursor synthesis gel, while the ideal CO2/CH4 selectivity of the membrane was gradually increased. Moreover, effects of synthesis conditions (such as H2O/SiO2 and RNOH/SiO2 ratios of precursor synthesis gel, crystallization time) on the single gas permeance performance of high silica SSZ-13 zeolite membranes were studied in detail. Medium H2O/SiO2 and RNOH/SiO2 ratios in the initial synthesis gel were crucial to prepare the good CO2 perm-selective SSZ-13 zeolite membrane. When the molar composition of precursor synthesis gel, crystallization temperature and time were 1.0 SiO2: 0.1 Na2O: 0.1 TMAdaOH: 80 H2O, 160 °C and 48 h, CO2 permeance and ideal CO2/CH4 selectivity of the SSZ-13 zeolite membrane were 0.98 × 10−7 mol/(m2·s·Pa) and 47 at 25 °C and 0.4 MPa. In addition, the SiO2/Al2O3 ratio of the corresponding SSZ-13 zeolite was 410 by X-ray fluorescence spectroscopy.

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A high performance ZSM-5 zeolite membrane is applied to remove H 2 O from the esteri cation of acetic acid and isopentanol by pervaporation. The in uences of reaction conditions on the isoamyl acetate yield are studied in detail. Compared with the traditional esteri cation of acetic acid and isopentanol, the esteri cation with "membrane extractor" has a well isoamyl acetate yield at low reaction temperature. With the reaction temperature, acetic acid/isopentanol molar ratio and e ective membrane surface area to esteri cation mixture ratio volume of 100°C, 3.0/1.0, 2.0 wt% NaHSO 4 , and 0.26 cm 2 /cm 3 , respectively, the isoamyl acetate yields was 98.39%, the membrane ux and separation factor (H 2 O to organic) were 0.21 kg·m 2 ·h 1 and 1040, respectively. Further, the ZSM-5 zeolite membrane shows good long-term stability and reproducibility for the pervaporation-esteri cation, the isoamyl acetate yields of the esteri cation-pervaporation for intermittent 8 times or continuous 160 h still remained at 97.73% and 98.30%, respectively. In addition, the ZSM-5 zeolite membrane still retained the typical MFI di raction peaks and morphology by XRD and SEM characterization after long-term PV-esteri cation .