Patent ID: 11884632
Assignee: ZHEJIANG HENGYI PETROCHEMICAL RESEARCH INSTITUTE CO., LTD.
Field: Chemical engineering (Chemistry)
Classification: CPC C  B  Y | IPC B  C

Claim 9:
10. The method of claim 4, wherein the preparation method of the catalyst comprises the following steps:
(b-1) mixing ethyl orthosilicate, ethanol, a metal source, tetrapropylammonium hydroxide and water to obtain a colloid mixture; wherein the molar ratio of ethyl orthosilicate calculated by SiO2, ethanol, tetrapropylammonium hydroxide and water is 1: (4-25): (0.06-0.45): (6-100); the weight ratio of the ethyl orthosilicate calculated by SiO2 relative to the metal source calculated by the metal element is (10,000-200,000): 1;
(b-2) subjecting the colloid mixture to a two-stage crystallization with an ethanol-hydrothermal system under variable temperatures, wherein the conditions of the two-stage crystallization with an ethanol-hydrothermal system under variable temperatures comprise: crystallizing at 40-80° C. for 0.5-5 days, and crystallizing at 80-130° C. for 0.5-5 days;
(b-3) sequentially filtering and drying the crystallization mother liquor obtained in step (b-2) to obtain a molecular sieve raw powder;
(b-4) crushing the molecular sieve raw powder, blending the crushed molecular sieve raw powder with a binder, and then carrying out rotary molding to obtain spherical particles; and
(b-5) roasting the spherical particles, contacting the roasted spherical particles with an alkaline buffer solution containing a nitrogen compound, and subsequently carrying out drying.