Synthesis and characterization of NaA zeolite membranes

NaA molecular sieve membrane;  hydrothermal method;  microwave synthesis;  Permeation gasification

A series of NaA-type zeolite membranes were synthesized on the outer surface of tubular α-Al2O3 ceramic tubes by in-situ hydrothermal secondary synthesis and microwave closed synthesis methods, and the effects of four raw material ratios and four crystallization methods on the synthesis of zeolite membranes were investigated, and the synthesis conditions were optimized. The synthesized membranes were characterized by pervaporation experiments of XRD, SEM, and ethanol aqueous solutions (purging the permeable side with nitrogen as osmotic thrust). The results showed that when the ratio of raw materials was Na2O∶Al2O3∶SiO2∶H2O=1∶1:3.6∶100, the molecular sieve membrane synthesized by the clear liquid coating crystal seed and microwave sealing had good selectivity for water and ethanol, and the separation factor was much greater than that of the blank tube, and 95% (wt) of ethanol aqueous solution passed through the membrane