Compound type cracking catalyst and preparation method thereof

Abstract

The invention discloses a compound type cracking catalyst which contains the following materials according to dry basis mass: 20-70% of in-situ crystallization Y-shaped molecular sieve / matrix composite material, 0.3-12% of MFI structural molecular sieve, and 30-75% of clay and inorganic oxide bonding agent. The in-situ crystallization Y-shaped molecular sieve / matrix composite material is the matrix formed after the in-situ crystallization is conducted on kaolin, and is one or a mixture of REY, REHY, HY, REUSY and USY formed by modification of Nay combined by surface in-situ crystallization. The catalyst has excellent capability of resisting heavy metal pollution and heavy oil cracking, and good coking selection.

Description

technical field [0001] The invention relates to a catalytic cracking catalyst and a preparation method thereof, in particular to a composite catalytic cracking catalyst containing an in-situ crystallized Y-type molecular sieve / matrix composite material and an MFI structure shape-selective molecular sieve and a preparation method thereof. Background technique [0002] Catalytic cracking is one of the most important processes in petroleum refining, and catalytic cracking catalyst is the core of the process. The main active component of catalytic cracking catalyst is Y-type molecular sieve. Its main auxiliary active component is a shape-selective molecular sieve with MFI structure, which is used to increase the yield of liquefied gas and propylene and to increase the octane number of catalytic gasoline. These two types of active components can be in the same granule or different granules, and the former has a better cracking synergistic effect. As far as the Y-type molecular ...

AI Technical Summary

Problems solved by technology

Its main disadvantage is that the in-situ crystallization type catalyst active component and matrix modulation are poor, and it is difficult to assemble a variety of functional molecular sieves, especially different types of Y-type molecular sieves and MFI structure shape-selective molecular sieves in the same particle, so the application effect and scope have more limitations

[0003] CN1334142A uses kaolin as a raw material, roasts kaolin at high temperature to obtain high-temperature roasted soil and metakaolin respectively, and mixes the two roasted soils, and in-situ hydrothermal crystallization under hydrothermal conditions to obtain a crystal with a NaY molecular sieve content of 40-90%. The product is then modified by ammonium, rare earth exchange and roasting to obtain different types of modified Y-type molecular sieves, but there is no oxidized rare earth deposition

[0006] CN1743422A adopts a nest body REY or REHY type zeolite composite material obtained by in-situ crystallization of kaolin as the active component of FCC catalyst, but there is no report on the in-situ crystallization of Y-type zeolite matrix composite material and MFI structure shape-selective molecular sieve binary compound

[0007] CN1533982A disclosed in its example 9-13 that the rare earth exchange process of its nest body Y-type zeolite composite material is exchanged with rare earth chloride at pH=4.5 for 2 hours after the exchange of ammonium salt, and then roasted after washing and filtering, and there is no Oxidized rare earth deposition, its ability to resist heavy metal pollution needs to be improved