The invention provides a catalytic
promoter for catalytic
cracking and a preparation method thereof.The catalytic
promoter comprises a modified ZSM-5
molecular sieve, a
phosphorus-containing compound and a binder, the preparation method of the modified ZSM-5
molecular sieve comprises the steps that 1, the ZSM-5
molecular sieve, an alkaline compound and water are mixed, stirred and filtered, and an alkali-modified ZSM-5 molecular
sieve is obtained; step 2, mixing the alkali modified ZSM-5 molecular
sieve, an acidic solution and a
zinc-containing compound, and stirring; step 3, mixing the
slurry obtained in the step 2 with a
phosphorus-containing compound, and stirring; and step 4, filtering,
drying and
roasting the
slurry obtained in the step 3 to obtain the modified ZSM-5 molecular
sieve. The modified ZSM-5 molecular sieve prepared by the method has rich mesopore and
macropore structures and good thermal and hydrothermal stability. The modified ZSM-5 molecular sieve prepared by the method can effectively promote the shape-selective
cracking reaction of
gasoline components in the catalytic
cracking process, improve the yield of liquefied gas and propylene, and improve the content of propylene in the liquefied gas at the same time.