Zeolite molecular sieve with multi-stage pore structure and preparation method and application of zeolite molecular sieve

Abstract

The present invention discloses a zeolite molecular sieve with a multi-stage pore structure and a preparation method and an application of the zeolite molecular sieve. The zeolite molecular sieve withthe multi-stage pore structure is prepared by adding a small amount of a cationic polymer structure directing agent in a one-step manner. Compared with conventional molecular sieves, the zeolite molecular sieve has a relatively high specific surface area and pore volume, and a rich pore structure, solves problems of cumbersome post-processing operations or use of expensive organic templates whenthe conventional preparation of the molecular sieve with the multi-stage pore structure is conducted. At the same time, after active metal components are loaded, carbon holding capacity of a catalystis enhanced, reaction stability of the molecular sieve is effectively improved, and the molecular sieve shows good reaction performance when applied in anaerobic aromatization reaction of methane.

Description

technical field [0001] The invention belongs to the technical field of energy and chemical catalysts, and in particular relates to a multi-stage pore structure zeolite molecular sieve and its preparation method and application. Background technique [0002] Since the discovery of zeolite molecular sieve, it has been widely used in petrochemical industry due to its rich specific surface area and pore structure. The characteristics of zeolites have also been discovered more and more thoroughly. Although some zeolite molecular sieves have been industrialized, with the conditions of various experimental reaction conditions, there are more stringent requirements for molecular sieves, such as modification by different methods to improve catalytic activity. Researchers have been exploring new techniques and methods for the synthesis of zeolite molecular sieves by modifying the molecular sieve itself to improve catalytic stability, and have prepared various forms of molecular sieves...

AI Technical Summary

Problems solved by technology

[0004] In order to prepare molecular sieves with mesoporous and macroporous structures, the existing technical methods often use acid-base treatment, recrystallization and other modifications and secondary synthesis to increase the specific surface area and pore volume of zeolite molecular sieves. However, the above processes are often cumbersome and need to be repeated. The modification of molecular sieves destroys the crystallinity and strength of molecular sieves to a certain extent, which is time-consuming and laborious; and the synthesis of hollow type HZSM-5, nano-sized HZSM-5, and core-shell type MCM-22 also requires the addition of expensive soft and hard templates. Pore ​​formation, not only harsh conditions, but also reduces the wear resistance of the catalyst in the fluidized bed

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