The invention relates to a ZSM-5 /
mordenite /
zeolite Y intergrowth
molecular sieve and a synthetic method thereof, which mainly solves the problems of singular aperture, rather weak acidity and
low activity of porous materials synthesized by the prior art. The invention adopts the technical proposal that the
nucleation and process of growth of the
molecular sieve are controlled properly by adding
crystal seeds containing
zeolite Y precursors in the synthetic process of the intergrowth
molecular sieve for producing the ZSM-5 /
mordenite /
zeolite Y intergrowth molecular
sieve, wherein the proportion of intergrowth phases is adjustable, and the synthesized ZSM-5 /
mordenite / zeolite Y intergrowth molecular
sieve adopts the compositions including the following mole relation: nSiO2:Al2O3, where n is between 4 and 400 in the formula, and the method is characterized in that the ZSM-5 / mordenite / zeolite Y intergrowth molecular
sieve has more than two phases and an XRD
diffraction pattern thereof has the d-space maximum value at the lengths of 14.3+-0.1, 13.58+-0.1, 11.21+-0.1, 10.04+-0.1, 9.47+-0.1, 9.09+-0.1, 6.6+-0.1, 5.7 +-0.1, 4.5+-0.1, 3.98+-0.05, 3.76+-0.04, 3.64+-0.04, 3.53+-0.04, 3.38+-0.02, 3.19+- 0.05 and 2.88+-0.1 angstroms, thereby solving the problems properly. The ZSM-5 / mordenite / zeolite Y intergrowth molecular sieve can be used for preparing
ethylene and propylene by catalytic-
cracking naphtha in the industrial production.