METHOD FOR PRODUCING NANO-SIZED ZEOLITE ZSM-5 STRUCTURAL TYPE WITH ADDITIONAL POROSITY INSIDE AND BETWEEN PARTICLES Russian patent published in 2023 - IPC C01B39/38 C01B39/04 

FIELD: inorganic chemistry; chemical engineering.

SUBSTANCE: methods for obtaining hierarchically structured micro-meso-macroporous materials with the properties of molecular sieves and solid acids, which can be used in various petrochemical and oil refining processes. A method is presented for obtaining a nano-sized zeolite of the ZSM-5 structural type in proton form with additional porosity inside the zeolite particles and between zeolite particles by treating the ZSM-5 structural type zeolite with an ammonium fluoride solution, characterized in that the method includes obtaining an initial synthesis mixture by mixing all the initial components: silicon source - tetraethyl orthosilicate, aluminum source - aluminum isopropoxide, template - tetra-n-propylammonium hydroxide in water, when mixing the template and the silicon source in a water bath at 70-80° C for 6 hours in one stage at a molar ratio of components in the synthesis mixture of tetraethyl orthosilicate: water: tetrapropylammonium hydroxide: aluminum isopropoxide equal to 1:4.2-4.4:0.2-0.3:0.006, crystallization at increased temperature and pressure in a Teflon autoclave under the conditions of hydrothermal-microwave synthesis, characterized by a radiation power of 900 W and a radiation frequency of 2.45 GHz, and providing a reaction mass temperature of 200-210° C, for 60 minutes, filtering the obtained product with separation of a solid precipitate, washing it with distilled water, drying at a temperature of 190° C for 2 hours and calcination at a temperature of 550-600° C to remove the template to obtain a zeolite, impregnate the resulting zeolite with an aqueous solution of ammonium fluoride by the method of complete moisture absorption, isolate the resulting solid precipitate, wash it with distilled water, dry for 24 hours and calcinate at 550° C within 2 hours to obtain the target product.

EFFECT: obtaining a nano-sized zeolite of the ZSM-5 structural type with a high silica modulus (more than 140), characterized by the presence of a developed system of mesopores both inside the zeolite particles and between the zeolite particles; carrying out treatment with a 30% aqueous solution of ammonium fluoride of nano-sized zeolite structural type ZSM-5 with a high silica modulus without destroying the structure of the zeolite; obtaining an additional amount of macro-pores in the zeolite; increase in specific surface area up to 406-425 m²/g.

2 cl, 3 dwg, 2 tbl, 13 ex