Catalytic cracking catalyst

Abstract

The invention relates to a catalytic cracking catalyst, which contains a modified Y-type molecular sieve, an alumina binder and clay, wherein the modified Y-type molecular sieve contains 5-12 wt% of oxidized rare earth and 0.1-0.7 wt% of sodium oxide, and has the total pore volume of 0.33-0.39 mL / g, the pore volume of the secondary pores with the pore size of 2-100 nm in the modified Y-type molecular sieve accounts for 10-25% of the total pore volume, the unit cell constant is 2.440-2.455 nm, the non-framework aluminum content in the modified Y-type molecular sieve is not more than 20% of thetotal aluminum content, the lattice collapse temperature is not below 1050 DEG C, and a ratio of the amount of B acid to the amount of L acid is not less than 2.50. According to the present invention,the catalytic cracking catalyst has advantages of high heavy oil conversion activity, low coke selectivity, high diesel yield, high liquefied gas yield, high light-oil yield and high total liquid recovery.

Description

technical field [0001] The invention relates to a heavy oil catalytic cracking catalyst and a preparation method thereof. Background technique [0002] At present, the industrial production of high-silicon Y-type zeolite mainly adopts the hydrothermal method. Rare earth-containing high-silicon Y-type zeolite can be prepared by performing multiple rare-earth ion exchanges and multiple high-temperature roasting on NaY zeolite. Zeolite has the following disadvantages: the structure of zeolite can be destroyed due to too harsh hydrothermal treatment conditions, and Y-type zeolite with a high silicon-aluminum ratio cannot be obtained; although the production of aluminum outside the framework is beneficial to improving the stability of zeolite and forming new acid centers, However, too much aluminum outside the framework reduces the selectivity of zeolite; in addition, many dealuminated holes in zeolite cannot be filled by silicon migrated from the framework in time, which often ...

AI Technical Summary

Problems solved by technology

Rare earth-containing high-silicon Y-type zeolite can be prepared by performing multiple rare-earth ion exchanges and multiple high-temperature roasting on NaY zeolite. Zeolite has the following disadvantages: the structure of zeolite can be destroyed due to too harsh hydrothermal treatment conditions, and Y-type zeolite with a high silicon-aluminum ratio cannot be obtained; although the production of aluminum outside the framework is beneficial to improving the stability of zeolite and forming new acid centers, However, too much aluminum outside the framework reduces the selectivity of zeolite; in addition, many dealuminated holes in zeolite cannot be filled by silicon migrated from the framework in time, which often causes lattice defects of zeolite, and the crystallization retention of zeolite is relatively low. Therefore, the thermal and hydrothermal stability of the rare earth-containing high-silicon Y-type zeolite prepared by the hydrothermal method is relatively poor, which is manifested in its low lattice collapse temperature, and its crystallinity retention rate and specific surface area retention after hydrothermal aging low rate

However, gas-phase ultrastable molecular sieves have no secondary pores

However, gas-phase ultrastable molecular sieves have no secondary pores

[0006] The performance of ultra-stable molecular sieves prepared by hydrothermal method or gas phase method in the prior art cannot well meet the current needs of processing heavy oil and inferior oil

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