Hydrocracking catalyst and preparation method thereof

Abstract

The invention discloses a hydrocracking catalyst and a preparation method thereof. The catalyst comprises a hydrogenation active metal component and a carrier prepared from a small grain Y type molecular sieve, amorphous silicon aluminum and alumina. According to the preparation method, the small grain Y type molecular sieve with the characteristics of great dealumination depth, good crystallinity retentivity and well-developed secondary pores is used as an acid component and cooperates with the amorphous silicon aluminum and the hydrogenation active metal component to form the hydrocracking catalyst. The hydrocracking catalyst has the advantages of better activity and stability, higher product selectivity and superior product quality.

Description

technical field [0001] The invention relates to a hydrocracking catalyst and a preparation method thereof, more specifically to a medium-oil type hydrocracking catalyst containing small grain Y-type molecular sieves and a preparation method thereof. Background technique [0002] With the increasing demand for middle distillates in the international oil market, more middle distillates need to be obtained from heavy oil, and the hydrocracking process is one of the important means of lightening heavy oil. Because the process has the characteristics of strong raw material adaptability, good product quality, flexible adjustment operation, high yield of middle distillate products, and flexible product structure, the status of hydrocracking process has become more and more important, especially for the current problems faced by our country. Due to the shortage of petroleum resources, increasingly stringent environmental protection requirements, and the structure of petroleum produc...

AI Technical Summary

Problems solved by technology

CN1382632A discloses a super-stabilizing method of small-grain Y-type zeolite, which is obtained by contacting the dry gas of silicon tetrachloride with small-grain NaY zeolite and washing it. The stability is poor, and the method is to deal with molecular sieves by gas-phase dealumination and silicon supplementation, which makes the thermal and hydrothermal stability of the product worse and the activity low

In this method, the raw material needs to be treated with ammonium hexafluorosilicate for dealumination of silicon first, and then undergo hydrothermal treatment and other treatments, so as to reduce the collapse of the molecular sieve skeleton structure and improve the crystallization retention of the molecular sieve. After treatment with ammonium hexafluorosilicate for dealumination and silicon supplementation, due to the isomorphic substitution of silicon and aluminum, the molecular sieve silicon oxide aluminum structure is relatively complete, and then hydrothermal treatment will form less secondary pores, and the proportion of secondary pores is low. Catalyst molecular sieve component, medium oil yield is low

[0008] In the preparation process of the existing method, small-grain NaY molecular sieves, silicon and aluminum are easily lost, the utilization rate of silicon is low, and the distribution of silicon and aluminum is not uniform, and it is easy to appear agglomeration, so the existing methods still cannot prepare small-grain NaY molecular sieves with high silicon-aluminum ratio and good thermal stability and hydrothermal stability

After subsequent modification, small-grain Y-type molecular sieves with complete structure, high crystallinity and more secondary pores cannot be obtained. As the cracking component of the catalyst, the yield of medium oil is low