| CPC C01B 39/38 (2013.01) [B01J 20/165 (2013.01); B01J 20/3021 (2013.01); B01J 20/3071 (2013.01); B01J 2220/46 (2013.01)] | 4 Claims |
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1. A method for preparing an organic-inorganic hierarchical ZSM-5, comprising the following steps:
S1, mixing a silicon source, an aluminum source, NaOH, and a first water to obtain a first mixture, stirring the first mixture until uniformly dispersed, and drying and grinding the first mixture after uniformly dispersed to obtain a hierarchical ZSM-5 precursor, wherein a ratio of a part by amount (in mol) of a substance of silicon in the silicon source to a part by amount (in mol) of a substance of aluminum in the aluminum source, to a part by amount (in mol) of a substance of the NaOH, to a part by volume (in mL) of the first water is (20-80):(1-4):(0.5-2):(35-55);
S2, mixing the hierarchical ZSM-5 precursor, sodium silicate, a seed, ethanol, and a second water to obtain a second mixture, and uniformly dispersing the second mixture to obtain a crystallized solution, wherein in parts by mass, a ratio of the hierarchical ZSM-5 precursor to the sodium silicate to the seed to the ethanol and to the second water in the S2 is (1.5-3):(0.3-0.6):(0.06-0.12):(10-20):(30-60), wherein the seed is a ZSM-5 molecular sieve; and
S3, mixing the crystallized solution with a hydrolyzed organosilane to obtain a resulting solution, subjecting the resulting solution to a hydrothermal crystallization at 160-180° C. for 48-72 h to obtain a product, and washing and drying the product to obtain the organic-inorganic hierarchical ZSM-5, wherein in parts by mass, a ratio of the hydrolyzed organosilane to the hierarchical ZSM-5 precursor in the crystallized solution is (1-10):(1-7); and an organosilane is hexamethyldisilazane and/or methyltriethoxysilane, the hydrolyzed organosilane is obtained by hydrolyzing the organosilane for 2-4 h, and a method for obtaining the hydrolyzed organosilane comprises: mixing 0.5-3 parts by mass of the organosilane with 8-15 parts by volume of a third water to obtain a third mixture, and stirring the third mixture at 20-30° C. for 2-4 h, wherein a unit of the parts by mass is g, and a unit of the parts by volume is mL.
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