Small grain NaY molecular sieve with high Si/Al ratio as well as preparation method of small grain NaY molecular sieve

Abstract

The invention provides a small grain NaY molecular sieve with high Si / Al ratio as well as a preparation method of the small grain NaY molecular sieve. The preparation method comprises following steps:a solid silicon source is mixed with a polymer, and the obtained mixture is subjected to high-temperature treatment under nitrogen protection to obtain a high-activity silicon source; the silicon source, an aluminum source, alkali liquor and water are mixed and aged to obtain a guidance agent; the high-activity silicon source, the guidance agent and water are mixed and stirred to obtain reactiongel; the reaction gel is crystallized, filtered, washed and dried to obtain the small grain NaY molecular sieve with high Si / Al ratio. The preparation method of the small grain NaY molecular sieve with the high Si / Al ratio can directly prepare a Y type molecular sieve with high Si / Al ratio in a short time. Compared with conventional methods, in the same feed molar ratio, the preparation method cansignificantly shorten the crystallization time, improve the Si / Al ratio of products and, the silicon source utilization and the solid content of the silicon source and aluminum source in the reactiongel is high. Furthermore, the yield of single kettle is doubled or more than the yield of the industrial sodium silicate at present.

Description

technical field [0001] The invention belongs to the technical field of catalysts, and relates to a high-silicon-aluminum-ratio small-grain NaY molecular sieve and a preparation method thereof. Background technique [0002] Y-type molecular sieve has a faujasite crystal structure, and as the main active component of the catalyst, it is widely used in catalytic cracking, hydrocracking, alkylation and other oil refining processes. [0003] The silicon-aluminum ratio of the Y-type molecular sieve has a great influence on the performance of the FCC catalyst. Increasing the skeleton silicon-aluminum ratio of Y-type molecular sieve helps to prolong the service life of the catalyst, and also directly affects the production of the catalyst and the distribution and economic benefits of catalytic cracking products. [0004] Y-type molecular sieves with a high silicon-aluminum ratio are basically realized through the process of post-treatment. The main methods of post-treatment include...

AI Technical Summary

Problems solved by technology

[0008] In order to solve the shortcomings of the existing technology for preparing NaY molecular sieves with high silicon-aluminum ratio and small crystal grains, the silicon-aluminum ratio is not greatly improved, the process operation is complicated, the crystallization time is long, the single-pot yield is low, and the silicon source utilization rate is low. The object of the present invention is to provide a NaY molecular sieve with high silicon-aluminum ratio and small crystal particles and its preparation method. The preparation method does not need to use any organic amine template agent, and utilizes the silicon source precursor processed by the polymer to synthesize high-silicon-aluminum in a short time and efficiently It is better than NaY molecular sieve and solves the mass transfer and heat transfer effect in the system during the scale-up process

Images