A catalytic cracking catalyst

Abstract

A catalytic cracking catalyst containing modified Y-type molecular sieve, alumina binder and clay; the CaO content of the modified Y-type molecular sieve is 0.3 to 4% by weight, RE 2 O 3 The content is 2-7% by weight, the sodium oxide content is 0.1-0.5% by weight, the total pore volume is 0.33mL / g-0.39mL / g, and the pore diameter of the modified Y-type molecular sieve is secondary pores of 2nm-100nm. The pore volume accounts for 10% to 25% of the total pore volume, the unit cell constant is 2.440nm to 2.455nm, the non-framework aluminum content in the modified Y-type molecular sieve accounts for no more than 20% of the total aluminum content, and the crystalline The grid collapse temperature should not be lower than 1050°C, and the ratio of B acid content to L acid content should not be lower than 2.30. The catalytic cracking catalyst has higher heavy oil conversion activity and lower coke selectivity, higher gasoline yield, isomeric C4 yield, and higher isomeric hydrocarbon content in gasoline.

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. Low

However, the Y molecular sieve prepared by this method has poor thermal and hydrothermal stability, and under certain conditions, it can only increase the content of isobutane, but cannot effectively increase the content of isomeric hydrocarbons in gasoline.

[0007] The performance of the ultra-stable molecular sieves prepared by the hydrothermal method or the gas phase method in the prior art cannot well meet the current needs of processing heavy oil and inferior oil and improving the quality of gasoline

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