The invention discloses a method for synthesizing a PHI-type
molecular sieve membrane on the surface of an α-Al2O3 support body. In the method, the support body pretreatment and the preparation of a
seed crystal synthesis solution are carried out first, and then the
crystal seed is introduced, and then the membrane is synthesized and washed and dried. The PHI type
molecular sieve membrane is obtained; the preparation of the
seed crystal synthesis solution is to configure alkali,
silicon source, aluminum source and deionized water according to the
molar ratio of Na2O, K2O, SiO2, Al2O3 and H2O, a1, b1, c1, 1 and d1, The source of alkali is Na2O and K2O, a1=1.5-2.5, b1=0.2-0.5, c1=4-8, d1=80-108; the
molecular sieve membrane synthesized by the present invention has
perfect crystal form, compact structure and good permeability, The synthesis process has high
repeatability, the membrane has a long service life, and is suitable for
industrial scale-up.