The invention provides a method for preparing a catalyst used for
methanol /
dimethyl ether high selectivity propylene preparation, and specifically provides a method for preparing nanometer layer structured ZSM-5
molecular sieve by employing an asymmetric gemini
quaternary ammonium surfactant as a template. The method comprises specific steps as follows: (1) preparing solution A by adding the template to a
mixed solution comprising water and
ethanol, and preparing solution B by adding aluminum sources to
sulfur solution; (2) slowly adding the B solution to the A solution, uniformly stirring the
mixed solution comprising the A solution and the B solution, and then adding the aluminum sources to form initial gel; and (3) moving the gel to a
crystallization kettle for
crystallization under 100-200 DEG C for 1-10 days. A ZSM-5
molecular sieve prepared according to the invention is in a nanometer layer structure with the thickness being 20-100 nm, the silica-
alumina ratio of the
molecular sieve can be adjusted, and the specific surface area and the pore volume of the molecular
sieve are quite large. In a
methanol /
dimethyl ether high selectivity propylene preparation reaction, the propylene selectivity and P / E ratio of the nanometer layer structured ZSM-5 molecular
sieve are higher than that of a conventional ZSM-5 molecular
sieve, and the service lifetime of the catalyst is longer.