CN107970987B

CN107970987B - Catalytic cracking catalyst and preparation method thereof

Info

Publication number: CN107970987B
Application number: CN201610921799.7A
Authority: CN
Inventors: 王丽霞; 刘宇键; 田辉平; 周翔; 袁帅; 欧阳颖; 庄立
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petrochemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petrochemical Corp
Priority date: 2016-10-21
Filing date: 2016-10-21
Publication date: 2019-12-27
Anticipated expiration: 2036-10-21
Also published as: CN107970987A

Abstract

A catalytic cracking catalyst and a preparation method thereof, wherein the catalyst comprises 5-65% of natural mineral substances, 10-60% of oxide binder, 24-75% of MFI structure molecular sieve and 0.1-15% of phosphorus additive; the proportion of the mesoporous protonic acid amount of the catalyst in the total acid amount is 20-70%. The preparation method of the catalyst comprises the steps of forming slurry containing the MFI structure molecular sieve, natural minerals and inorganic oxide binders, spray drying, treating with alkali and composite acid and introducing phosphorus additives. The catalytic cracking catalyst is used for catalytic cracking of petroleum hydrocarbon and has higher propylene yield and BTX yield.

Description

Catalytic cracking catalyst and preparation method thereof

Technical Field

The invention relates to a catalytic cracking catalyst, a preparation method and application thereof.

Background

The low-carbon olefin such as ethylene, propylene, butylene and the like is an essential chemical raw material and can be used for synthesizing resin, fiber, rubber and the like. Propylene is an important raw material for manufacturing petrochemical products, which is second only to ethylene, and is mainly used for producing chemical products such as polypropylene, acrylonitrile, propylene oxide and the like. At present, propylene is mainly derived from the by-product of ethylene production by thermal cracking at home and abroad, and the second largest source of propylene is the FCC unit, which provides about 30% of the demand, and in the united states, the FCC unit provides half of the demand of propylene for petrochemical products.

In recent years, the demand for propylene has increased rapidly, and by the prediction of HIS, the global propylene consumption has increased by 2016 at an average rate of about 5% which is greater than the rate of ethylene increase by 3.4%. However, the steam cracking propylene/ethylene ratio cannot be flexibly adjusted. And the reaction temperature is up to 840-860 ℃, and the energy consumption accounts for about 40% of the energy consumption of the petrochemical industry. Thus, the large production of propylene by FCC is an effective and efficient way to meet the growing demand.

Since the 80 s of the last century, catalysts containing shape selective molecular sieves ZSM-5 began to be put into industrial use on FCC units to increase the production of C₃ ^＝。

The ZSM-5 molecular sieve synthesized by Mobil corporation firstly has a three-dimensional pore channel structure, and is formed by intersecting Z-shaped ten-membered ring pore channels and straight-tube-shaped ten-membered ring pore channels, and the pore diameters are respectivelyAndthe unique pore channel structure of the composite material enables the composite material to show excellent performance in reactions such as isomerization and shape-selective cracking. But also because the pore channel structure is narrow, larger reactant molecules are difficult to enter the crystal pore channel for reaction, so that the conversion rate of larger hydrocarbon molecules is very low in the catalytic cracking reaction; in addition, the generated larger product molecules are difficult to diffuse out of the molecular sieve pore channels, so that secondary reaction is easy to occur, and the activity of the catalyst and the selectivity of a target product are reduced. The problem is even more pronounced when the reactant is heavy oil.

CN103357429B proposes a preparation method of a catalytic cracking catalyst for increasing propylene yield, which comprises mixing mesoporous H-ZSM-5 molecular sieve, USY molecular sieve, natural clay and binder, pulping, drying and roasting to obtain the catalyst.

However, the prior art does not disclose how to further increase the propylene yield of a catalyst comprising a molecular sieve of MFI structure.

Disclosure of Invention

The invention aims to solve the technical problem of providing a fluidized bed catalytic cracking catalyst, wherein the catalyst contains an MFI structure molecular sieve, and has higher propylene yield when being used for converting hydrocarbon oil.

The invention provides a catalytic cracking catalyst, which comprises (a) 5-65% of natural mineral substances in dry basis by taking the weight of the catalyst as a reference; (b) 10% -60% of oxide; and (c) 24% to 75% on a dry basis of a first molecular sieve, the first molecular sieve being a MFI structure molecular sieve; and D) with P₂O₅0.1 to 15 percent of phosphorus additive; the proportion of the mesoporous protonic acid amount of the catalytic cracking catalyst in the total acid amount is 20-70%, for example 25-65%. The total specific surface area of the catalyst is preferably greater than 240m²/g。

Preferably, the proportion of the mesopore volume of the catalytic cracking catalyst to the total pore volume is 35% to 60%, for example 40% to 60% or 45% to 58%. The mesoporous volume of the catalyst is 0.14-0.35 ml/g, such as 0.15-0.30 ml/g. The mesoporous is a pore with the pore diameter of 2-100 nm.

Preferably, the total specific surface area (also called specific surface area) of the catalytic cracking catalyst is 240-350 m²A/g, for example, of 250 to 320m²/g。

The catalytic cracking catalyst provided by the invention has more mesoporous protonic acid, and the proportion of the mesoporous protonic acid in the total acid amount is 20-70%, such as 25-65%, preferably, such as 25-50% or 30-55%.

The mesoporous pore volume and the total pore volume of the catalytic cracking catalyst are measured by adopting a nitrogen adsorption BET specific surface area method; the total specific surface area of the catalyst is measured by adopting a nitrogen adsorption BET specific surface area method; the mesoporous protonic acid of the catalyst has a kinetic diameter ofThe 2, 6-di-tert-butylpyridine molecule can contact with protonic acid. Mesoporous protonMeasuring the acid amount by adopting a 2, 6-di-tert-butylpyridine adsorption infrared acid method; total acid content adopts NH₃The TPD method is used for the measurement.

Preferably, the phosphorus additive content in the catalytic cracking catalyst is P₂O₅From 0.1 to 15% by weight, for example from 1 to 13% by weight or from 1.5 to 8% by weight or from 0.5 to 6.5% by weight or from 2 to 5% by weight.

The catalytic cracking catalyst provided by the invention contains natural minerals, wherein the natural minerals are one or more of kaolin, halloysite, montmorillonite, diatomite, attapulgite, sepiolite, halloysite, hydrotalcite, bentonite and rectorite; the oxide binder is one or more of silicon oxide, aluminum oxide, zirconium oxide, titanium oxide and amorphous silica-alumina binder.

The catalytic cracking catalyst provided by the invention contains a molecular sieve with an MFI structure, wherein the molecular sieve with the MFI structure can be a sodium type molecular sieve with the MFI structure, and can also be a modified molecular sieve with the MFI structure obtained by modifying the sodium type molecular sieve with the MFI structure, such as a hydrogen type molecular sieve with the MFI structure, an ammonium type molecular sieve with the MFI structure, and an MFI structure molecular sieve containing phosphorus and/or transition metals, wherein the transition metals are one or more of RE, Fe, Ni, Co, Cu, Mn, Zn, Sn, Bi and Ga. The MFI structure molecular sieve is one or more of a ZSM-5 molecular sieve, a ZSP molecular sieve and a ZRP molecular sieve, wherein the ZSM-5 molecular sieve can be NaZSM-5 or a molecular sieve obtained by modifying a NaZSM-5 molecular sieve, such as HZSM-5, ammonium ZSM-5, ZSM-5 containing phosphorus and/or transition metals, wherein the transition metals are one or more of RE, Fe, Ni, Co, Cu, Mn, Zn, Sn, Bi and Ga.

The invention also provides a preparation method of the catalytic cracking catalyst, which comprises the steps of preparing a microspherical composition comprising a first molecular sieve, natural minerals and an oxide binder, namely the microspherical composition of the first composition, and modifying the microspherical composition of the first composition; the microsphere modification treatment of the first composition comprises the following steps:

a. putting the first composition microspheres into an alkaline solution for treatment, filtering and washing to obtain alkali-treated first composition microspheres;

b. and c, treating the alkali-treated first composition microspheres obtained in the step a in a composite acid solution consisting of fluosilicic acid, organic acid and inorganic acid, filtering and washing, optionally carrying out ammonium exchange sodium washing treatment, optionally filtering and optionally washing, and optionally drying to obtain the composition microspheres rich in mesopores.

c. Introducing a phosphorus additive and a metal additive into the composition microspheres rich in mesopores;

d. roasting at 400-800 deg.c for at least 0.5 hr.

In the preparation method of the catalytic cracking catalyst provided by the invention, the alkaline solution in step a comprises an alkaline compound, preferably, the alkaline compound is a strongly alkaline inorganic compound, for example, the alkaline compound is one or more of sodium hydroxide, potassium hydroxide, lithium hydroxide, ammonium hydroxide and high-alkali sodium metaaluminate. The alkaline solution used in step a is at least one selected from the group consisting of sodium hydroxide solution, potassium hydroxide solution, lithium hydroxide solution, ammonium hydroxide solution and high-alkali sodium metaaluminate solution. The alkaline solution is an aqueous solution of an alkaline compound.

According to the method for preparing the catalytic cracking catalyst provided by the invention, in one embodiment, the alkaline solution used in the step a preferably comprises high-alkali sodium metaaluminate, preferably high-alkali sodium metaaluminate solution. Preferably, in the high-alkali sodium metaaluminate solution, Na₂O content of 270-310 g/L, Al₂O₃The content is 30-50 g/L, and the solution density is 1.25-1.45 g/mL.

According to the preparation method of the catalytic cracking catalyst provided by the invention, the treatment in the step a comprises the following steps: comprises contacting the microspheres of the first composition with an alkaline solution, wherein the alkaline solution comprises an alkaline compound, and the microspheres of the first composition are mixed with an alkali metal oxide (ammonium hydroxide as NH) based on the weight of the alkali metal oxide₃The weight ratio of the basic compound is 1 (0.01-0.35). Preferably, the microspheres of the first composition are mixed with the alkali metal oxide (oxyhydrogen) on a dry basisBy conversion of ammonium to NH₃In terms of the weight ratio of the basic compounds) is 1: (0.05-0.25) or 1: (0.01-0.15).

The preparation method of the catalytic cracking catalyst provided by the invention comprises the following steps: the weight ratio of the first composition microspheres to water on a dry basis is 1: (5-20).

The preparation method of the catalytic cracking catalyst provided by the invention comprises the following steps: the temperature of the treatment is 25 ℃ to 100 ℃, preferably 40 ℃ to 75 ℃ or 45 ℃ to 65 ℃, and the treatment time is 10 minutes or more, for example, 0.2 to 6 hours, or 0.2 to 4 hours, or 0.3 to 3 hours.

In the preparation method of the catalytic cracking catalyst, in the step b, the alkali-treated first composition microspheres obtained in the step a are treated in a solution of a composite acid consisting of fluosilicic acid, organic acid and inorganic acid, wherein the treatment is to contact the alkali-treated first composition microspheres with a composite acid aqueous solution consisting of fluosilicic acid, organic acid and inorganic acid for 10 minutes or more, such as 0.2-10 hours or 0.5-6 hours, filter and optionally wash. The filter cake obtained by filtration or the filter cake after washing can also be contacted with an ammonium salt solution to carry out an ammonium exchange sodium washing treatment so that the sodium oxide in the obtained catalyst is not more than 0.2 wt%, preferably not more than 0.15 wt%. The ammonium salt may be a commonly used ammonium salt, for example, at least one selected from the group consisting of ammonium chloride, ammonium sulfate, ammonium carbonate, ammonium bicarbonate, ammonium acetate, and ammonium nitrate.

In the step b, the treatment temperature is 25-100 ℃, for example, 30-75 ℃ or 45-65 ℃.

According to the preparation method of the catalytic cracking catalyst, at least one of the organic acid selected from ethylenediamine tetraacetic acid, oxalic acid, acetic acid, citric acid and sulfosalicylic acid in the step b is preferably oxalic acid, and at least one of the inorganic acid selected from hydrochloric acid, sulfuric acid and nitric acid is preferably hydrochloric acid. Preferably, the organic acid in step b is oxalic acid, and the inorganic acid is hydrochloric acid.

In the preparation method of the catalytic cracking catalyst provided by the invention, the treatment conditions in the step b are as follows: the weight ratio of the first composition microspheres, the fluosilicic acid, the inorganic acid and the organic acid is 1 (0.003-0.3) to 0.01-0.45 to 0.01-0.55 on a dry basis.

Preferably, in the preparation method of the catalytic cracking catalyst provided by the invention, the treatment conditions in the step b are as follows: the weight ratio of the first composition microspheres, the fluosilicic acid, the organic acid and the inorganic acid is 1 (0.005-0.3): (0.02-0.3): or 1 (0.005-0.17): 0.015-0.15): 0.02-0.15): or 1 (0.005-0.1): 0.02-0.2): 0.02-0.15. The weight ratio of the fluosilicic acid to the first composition microspheres is preferably (0.005-0.3): 1 or (0.005-02): 1 or (0.005-0.17): 1 or (0.005-0.1): 1; the weight ratio of the organic acid to the first composition microspheres is preferably (0.02-0.3): 1 or (0.015 to 0.15): 1 or (0.02-0.2): 1; the weight ratio of the inorganic acid to the first composition microspheres is preferably (0.01-0.2): 1 (or 0.02-0.3): 1, or (0.02-0.15): 1 or (0.02-0.15): 1.

in the preparation method of the catalytic cracking catalyst provided by the invention, in the step b, the weight ratio of water to the first composition microspheres calculated on a dry basis is 3-20: 1 is, for example, 4 to 15: 1 or 5-10: 1.

the preparation method of the catalytic cracking catalyst according to the present invention, wherein the ammonium exchange sodium wash exchange process of step b contacts the composition obtained by the complex acid treatment with an ammonium salt solution, wherein the ammonium salt may be a commonly used ammonium salt, for example, at least one selected from the group consisting of ammonium chloride, ammonium sulfate, ammonium carbonate, ammonium bicarbonate, sodium acetate and ammonium nitrate. Ammonium salt exchange sodium wash treatment followed by filtration, optionally washing, to wash out exchanged sodium and non-exchanged ammonium salts in the catalyst. For example, in ammonium exchange sodium washing, the weight ratio of an ammonium salt solution to the composition obtained by the complex acid treatment is 5-20: 1, the concentration of the ammonium salt solution is 1-10 wt%, the contact temperature is 30-80 ℃, and the contact time is 0.5-2 hours.

In the preparation method of the catalytic cracking catalyst provided by the invention, the washing in the step b is a conventional method, for example, according to a weight ratio of the first composition microspheres to water of 1: and leaching with water in a weight ratio of 5-10. In the washing, the washing liquid after washing is generally neutral, for example, the pH value is 6 to 8.

In the preparation method of the catalytic cracking catalyst provided by the invention, the step c of introducing the phosphorus additive comprises the step of contacting the composition microspheres rich in mesopores with a phosphorus-containing compound. The contacting is performed to effect impregnation and/or ion exchange to introduce the phosphorus additive and the phosphorus into the catalyst. The phosphorus additive may be introduced into the mesopore-rich composition microspheres by one or more contacts with the composition. The phosphorus-containing compound may be selected from one or more of phosphoric acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate and ammonium phosphate.

According to the preparation method of the catalytic cracking catalyst, the roasting treatment conditions in the step d comprise the following steps: the atmosphere of the roasting treatment is air atmosphere, nitrogen atmosphere or water vapor atmosphere or the mixture atmosphere of the above atmospheres; the roasting temperature is 400-800 ℃, and the roasting time is 0.5-8 hours. Preferably, the roasting treatment is carried out at 500-600 ℃ for 0.5-8 hours.

According to the method of the present invention, the baking process in step d may be wet baking, and the wet baking is performed in an atmosphere of 1 to 100 vol% of water vapor (i.e., the atmosphere contains 1 to 100 vol% of water vapor), more preferably 100 vol% of water vapor.

The catalytic cracking catalyst provided by the invention can be used for producing low-carbon olefin by catalytic cracking of hydrocarbon oil, and the method for producing low-carbon olefin by catalytic cracking of hydrocarbon oil comprises the step of contact reaction of hydrocarbon oil and the catalytic cracking catalyst provided by the invention. The reaction conditions can refer to the existing conditions for producing the low-carbon olefin by catalytic cracking. The hydrocarbon oil is petroleum hydrocarbon, and can be partial fraction petroleum hydrocarbon or full fraction petroleum hydrocarbon. The catalytic cracking catalyst is suitable for producing low-carbon olefin by cracking heavy oil, such as one or more of vacuum residue, atmospheric residue, catalytic cracking light cycle oil, catalytic cracking heavy cycle oil, solvent deasphalted oil, lubricating oil refined oil and hydrotreated oil obtained by hydrotreating the above oil products.

The catalytic cracking catalyst provided by the invention has rich mesoporous structure, proper mesoporous acidity and higher hydrothermal stability, is used for heavy oil catalytic cracking reaction, and has the advantages of higher conversion rate, high propylene yield, high BTX yield and particularly good propylene selectivity. Compared with the existing cracking catalyst, the catalytic cracking catalyst provided by the invention has higher hydrocarbon oil cracking activity, higher conversion rate and higher propylene yield and BTX yield. According to the preparation method of the catalytic cracking catalyst, the MFI structure molecular sieve, the natural mineral substances and the binder component are prepared into the microsphere composition, then the pore structure and the acidity of the catalyst are further modulated by the alkali-acid coupling treatment method, and phosphorus and metal modification is performed after the catalyst is prepared, so that the performance of the whole catalyst can be improved, the stability of the catalyst and the selectivity of low-carbon olefin and BTX are improved, and the efficiency of phosphorus and metal modification on the catalyst can be improved.

Detailed Description

The catalytic cracking catalyst provided by the invention contains natural minerals, wherein the natural minerals comprise one or more of kaolin, halloysite, montmorillonite, diatomite, attapulgite, sepiolite, halloysite, hydrotalcite, bentonite, rectorite and the like. The content of the natural mineral in the catalyst provided by the invention is 5 wt% to 65 wt%, preferably 8 wt% to 60 wt%, for example 10 wt% to 50 wt%, or 8 wt% to 45 wt%, or 10 wt% to 55 wt%, based on the total amount of the catalyst, in terms of weight percentage, on a dry basis.

The catalytic cracking catalyst provided by the invention contains an oxide binder component, wherein the oxide is one or a mixture of more than two of silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, amorphous silica-alumina and aluminum phosphate material, and the oxide binder is derived from sol-state substances of corresponding oxide precursors such as oxides, such as one or more of silica sol, alumina sol, pepto-pseudo-boehmite, silicon-alumina sol and phosphorus-containing alumina sol. The oxide binder is present in an amount of 10 to 60 wt.%, preferably 15 to 55 wt.%, for example 10 to 30 wt.%, or 25 to 50 wt.%, or 20 to 50 wt.%, calculated as the weight percentage of oxide based on the total amount of catalyst. .

The catalytic cracking catalyst provided by the invention contains a first molecular sieve, wherein the first molecular sieve is an MFI structure molecular sieve. The MFI structure molecular sieve can be a sodium type MFI structure molecular sieve, and can also be an MFI structure molecular sieve obtained by subjecting a sodium type MFI structure molecular sieve to various modification methods, such as an ammonium type MFI structure molecular sieve obtained by ammonium exchange, a hydrogen type MFI structure molecular sieve, and a modified MFI structure molecular sieve containing one or more of phosphorus and transition metals; MFI structure molecular sieves such as ZSM-5, which may be NaZSM-5, or molecular sieves modified from NaZSM-5 molecular sieves such as HZSM-5, ZSM-5 containing phosphorus and transition metals; wherein the transition metal is one or more of RE, Fe, Ni, Co, Cu, Mn, Zn, Sn, Bi and Ga. The content of the first molecular sieve is 24 to 75 wt%, preferably 30 to 65 wt%, for example 30 to 55 wt% or 35 to 50 wt%.

The cracking catalyst provided by the invention can also contain an auxiliary component. The content of the auxiliary component is not more than 30% by weight, for example 0 to 30% by weight or 0.5 to 25% by weight, based on the dry basis. The additive component is at least one of a desulfurization additive component, a denitration additive component and a combustion improver component.

The cracking catalyst provided by the invention also can contain a second molecular sieve, wherein the second molecular sieve is other molecular sieves except the first molecular sieve, and the molecular sieves are often combined with an active component of a catalytic cracking catalyst. The second molecular sieve is contained in an amount of 0 to 25 wt%, for example, 0.5 to 20 wt%. Such as one or more of IMF structure molecular sieves, SAPO molecular sieves, MCM molecular sieves, BEA structure molecular sieves, ferrierite. The molecular sieve with BEA structure can be a sodium type BEA structure molecular sieve, and can also be a modified BEA structure molecular sieve obtained by modifying the sodium type BEA structure molecular sieve, such as a hydrogen type BEA structure molecular sieve, an ammonium type BEA structure molecular sieve, a BEA structure molecular sieve containing phosphorus and transition metals, wherein the transition metals are RE, Fe, Ni and CoThe BEA structure molecular sieve is beta molecular sieve, can be sodium type beta molecular sieve, and can also be modified beta molecular sieve obtained by modifying sodium type beta molecular sieve, such as H beta, NH₄Beta molecular sieve, phosphorus, and one or more transition metals such as one or more of RE, Fe, Ni, Co, Cu, Mn, Zn, Sn, Bi, and Ga. The ferrierite such as Fer molecular sieve can be sodium type Fer molecular sieve, also can be modified Fer molecular sieve obtained by modifying sodium type Fer molecular sieve, such as HFer, NH₄A Fer molecular sieve modified with one or more of a Fer molecular sieve, phosphorus and a transition metal, such as one or more of RE, Fe, Ni, Co, Cu, Mn, Zn, Sn, Bi and Ga.

In the preparation method of the catalytic cracking catalyst provided by the invention, a microspherical composition comprising an MFI structure molecular sieve, natural minerals and an oxide binder is prepared, and then modified. A microspheroidal composition comprising an MFI structure molecular sieve, a natural mineral, an oxide binder may be prepared by: the microsphere composition is prepared by pulping, spray drying and optionally roasting the MFI structure molecular sieve, natural minerals, an oxide binder component precursor, an optional second molecular sieve, an optional auxiliary agent component and water, and is called as a first composition microsphere. The spray drying and roasting are the prior art, and the invention has no special requirements. For example, the temperature of the calcination may be 300 to 650 ℃ or 350 to 500 ℃, and the calcination time may be 0.5 to 10 hours. The firing may be carried out in an air atmosphere, a nitrogen atmosphere, or an atmosphere containing water vapor.

The preparation method of the catalytic cracking catalyst provided by the invention comprises the steps of mixing and pulping the natural minerals, the first molecular sieve, the oxide binder such as oxide sol and/or oxide gel and water. The components are used in such amounts that the final catalyst contains, based on the total weight of the catalyst, 5 to 65 wt% of natural minerals, 10 to 60 wt% of oxides and 24 to 75 wt% of a first molecular sieve. More preferably, the components are used in amounts such that the final catalyst comprises: the natural mineral content is 5 to 50 wt%, for example 8 to 45 wt%, on a dry basis, the first molecular sieve content is 30 to 65 wt%, for example 30 to 50 wt%, on a dry basis, and the oxide binder content is 15 to 55 wt%, for example 20 to 50 wt%, on an oxide basis.

According to the preparation method of the catalytic cracking catalyst provided by the invention, the natural mineral substances comprise one or more of kaolin, halloysite, montmorillonite, diatomite, attapulgite, sepiolite, halloysite, hydrotalcite, bentonite, rectorite and the like. The natural mineral is used in an amount of 5 wt% to 65 wt%, preferably 5 wt% to 50 wt%, more preferably 8 wt% to 45 wt%, based on the total amount of the catalyst.

The invention provides a preparation method of the catalytic cracking catalyst, wherein the oxide binder precursor is selected from one or more of silica, alumina, zirconia, titania, amorphous silica-alumina and aluminum phosphate material sol or gel, and the oxide binder precursor is selected from one or more of silica sol, alumina sol, peptized pseudo-boehmite, silica-alumina sol and phosphorus-containing alumina sol. The oxide binder precursor is used in an amount such that the oxide binder content in the resulting catalytic cracking catalyst is from 10 wt% to 60 wt%, for example from 15 wt% to 55 wt%, preferably from 20 wt% to 50 wt%, for example from 25 wt% to 50 wt%, in terms of the weight percent of oxide based on the total catalyst.

According to the preparation method of the catalytic cracking catalyst provided by the invention, the MFI structure molecular sieve can be a sodium type MFI structure molecular sieve, and can also be an MFI structure molecular sieve obtained by subjecting a sodium type MFI structure molecular sieve to various modification methods, such as an ammonium type MFI structure molecular sieve obtained by ammonium exchange, a hydrogen type MFI structure molecular sieve, and a modified MFI structure molecular sieve containing one or more of phosphorus and transition metals. The MFI structure molecular sieve, such as ZSM-5, may be NaZSM-5, or a molecular sieve modified with NaZSM-5 molecular sieve, such as HZSM-5, ZSM-5 containing phosphorus and/or transition metal. Wherein the transition metal is one or more of RE, Fe, Ni, Co, Cu, Mn, Zn, Sn, Bi and Ga. The amount of the first molecular sieve is such that the catalyst obtained contains 24 to 75 wt%, preferably 30 to 65 wt%, for example 30 to 55 wt%, or 30 to 50 wt%, or 35 to 50 wt% of the first molecular sieve based on the total amount of the catalyst on a dry basis.

According to the preparation method of the catalyst provided by the invention, preferably, the weight ratio of the natural mineral substance in terms of dry basis, the first molecular sieve in terms of dry basis and the oxide binder in terms of oxide in the first composition microspheres is 5-65: 24-75: 10-60, preferably 5-55: 25-55: 15-55, more preferably 8-45: 30-50: 20 to 50. The first composition microspheres comprise 5-65 wt% of natural mineral substance, 10-60 wt% of oxide binder and 24-75 wt% of first molecular sieve on a dry basis, wherein the natural mineral substance, the oxide binder and the first molecular sieve are respectively in a dry basis, and preferably, the first composition microspheres comprise 5-55 wt% of natural mineral substance, 15-55 wt% of oxide binder and 25-55 wt% of first molecular sieve on a dry basis. More preferably, the first composition microspheres contain 8 wt% to 45 wt% of a natural mineral on a dry basis, 20 wt% to 50 wt% of an oxide binder on an oxide basis, and 30 wt% to 50 wt% of a first molecular sieve on a dry basis.

The preparation method of the catalyst provided by the invention comprises the following steps of mixing a precursor of an inorganic oxide binder, such as pseudo-boehmite, alumina sol, silica-alumina gel or a mixture of two or more of the pseudo-boehmite, the alumina sol, the silica-alumina sol and the silica-alumina gel, with a natural mineral such as kaolin and water (such as decationized water and/or deionized water) to prepare a slurry with a solid content of 10-50 wt%, uniformly stirring, optionally adjusting the pH of the slurry to 1-4, such as 2-3, with an inorganic acid such as hydrochloric acid, nitric acid, phosphoric acid or sulfuric acid, uniformly stirring, optionally standing at 20-80 ℃ for 0-2 hours, such as 0.3-2 hours, then adding a first molecular sieve, wherein the first molecular sieve is an MFI structure molecular sieve, uniformly stirring to form a first composition slurry, and the solid content of the first composition slurry is 20-45 wt%, for example, spray drying to obtain microspherical composition. And then roasting the microspherical composition for 0.5 to 6 hours at 300 to 650, preferably 350 to 550 ℃, for example, to obtain the first composition microsphere. If the catalytic cracking catalyst includes a promoter component and/or a second molecular sieve, the first composition slurry also contains the promoter component and the second molecular sieve, which are introduced into the first composition slurry at any step prior to spray drying.

The washing according to the present invention is well known to those skilled in the art and, without particular reference thereto, generally refers to water washing, for example, the molecular sieve may be rinsed with 5 to 10 times the weight of the molecular sieve.

According to the method provided by the invention, in the step c, a phosphorus additive is introduced into the composition microspheres rich in mesopores obtained in the step b. Preferably, the introduction is such that the phosphorus additive content in the resulting catalytic cracking catalyst is as P₂O₅From 0.1 to 15% by weight, for example from 1 to 13% by weight or from 1.5 to 8% by weight or from 0.5 to 6.5% by weight or from 2 to 5% by weight.

The catalytic cracking catalyst prepared by the preparation method provided by the invention has more mesoporous protonic acid, and the proportion of the mesoporous protonic acid in the total acid amount is 20-70%, such as 25-65%, preferably, such as 25-50% or 30-55%.

The total specific surface area of the catalytic cracking catalyst prepared by the method is more than 240m²A total specific surface area (also referred to as specific surface area) of 240 to 350m²A/g, for example, of 250 to 320m²/g。

According to the preparation method of the catalytic cracking catalyst provided by the invention, the proportion of the mesoporous volume of the prepared catalytic cracking catalyst in the total pore volume is 35-60%, such as 40-60%, 45-58% or 35-45%. The mesoporous volume of the catalytic cracking catalyst is 0.14-0.35 ml/g, such as 0.15-0.30 ml/g.

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation. The instruments and reagents used in the examples of the present invention are those commonly used by those skilled in the art unless otherwise specified.

The influence of the catalytic cracking catalyst on the propylene yield and the BTX yield in the catalytic cracking of petroleum hydrocarbon is evaluated by using raw oil ACE. The catalyst is aged for 14 hours at 800 ℃ under 100 percent water vapor, and is evaluated on fixed fluidized bed micro-reaction ACE, wherein the raw oil is hydrotreated oil (the composition and physical properties are shown in Table 3), the evaluation conditions are that the reaction temperature is 535 ℃, the regeneration temperature is 650 ℃, and the agent-oil ratio is 5 weight percent.

The specific surface area of the present invention was measured by the standard method of GBT 5816-1995.

The pore volume of the present invention was determined using standard methods of GB/T5816-1995.

The total acid content of the invention adopts NH₃TPD method see research methods for solid catalysts, petrochemical, 30(12), 2001: 952.

the mesoporous protonic acid of the method is determined by adopting a 2, 6-di-tert-butylpyridine adsorption infrared acidity method. The specific method comprises the following steps: the catalyst was pressed to 10mg/cm²Into a band of CaF₂In the infrared bath of the window. Vacuumizing at 400 ℃, then reducing the temperature to 150 ℃, adsorbing the 2, 6-di-tert-butylpyridine for 15 minutes, and then vacuumizing for 1 hour. And cooling to room temperature to collect a spectrogram, and calculating the amount of the protonic acid. See Applied Catalysis A, General, 294, 2005: 92.

na of the invention₂O、P₂O₅And the content of the metal additive is determined by adopting a GB/T30905-2014 standard method.

The RIPP standard method can be found in petrochemical analysis, Yangcui and other editions, 1990 edition.

The following examples illustrate the catalysts and the process for their preparation according to the invention, in which the raw materials used have the following properties: kaolin (Kaolin, China Suzhou, with a solid content of 75 wt.%), montmorillonite (Red Stone Bentonite, Kogyo, Liaoning, with a solid content of 75 wt.%), alumina sol (Qilu division, a limited Chinese petrochemical catalyst, with an alumina content of 22.5 wt.%), silica sol (Qingdao limited maritime chemical, with a silica content of 25.5 wt.%, a pH of 3.0), ZSM-5 molecular sieve (Qilu division, a limited Chinese petrochemical catalyst, with a NaZSM-5, a silica to alumina ratio (Si/Al molar ratio, the same applies hereinafter) of 22, and a sodium oxide content of 2.5 wt.%). The ZRP-1 molecular sieve is produced by Qilu Branch of China petrochemical catalyst Co., Ltd, and has a silicon-aluminum ratio of 20.

The solid content is the weight ratio of the solid product obtained by roasting the material at 800 ℃ for 1 hour to the material.

Example 1

333.3g of alumina sol and 160g of kaolin are mixed, and are prepared into slurry with the solid content of 28 weight percent by using decationized water, after stirring for 2 hours, slurry containing 105g (calculated by dry basis) of ZSM-5 molecular sieve is added, the mixture is uniformly stirred to form composition slurry (the solid content is 30 weight percent), spray drying is carried out to prepare composition microspheres, and then the composition microspheres are roasted for 1 hour at 500 ℃ to prepare the first composition microspheres A1.

200g of the first composition microspheres A1 (dry basis weight, the same applies hereinafter) prepared above were taken, water was added and slurried to obtain a slurry having a solid content of 10% by weight, and 15.1g of a high-alkali sodium metaaluminate solution (Na) was added₂O is 290g/L, Al₂O₃40g/L, the solution density is 1.353g/mL), heating to 50 ℃, stirring at constant temperature for 0.5h, filtering, and washing to neutrality (the washing to neutrality means that the washing liquid after washing is neutral, and the pH is 6-8); adding water into the filter cake, pulping to obtain slurry with the solid content of 10 wt%, adding 6.2g of oxalic acid while stirring, then adding 54g of hydrochloric acid (the mass fraction is 10%) and 653.3g of fluosilicic acid (the concentration is 3 wt%), heating to 50 ℃, stirring for 1h at constant temperature, filtering, washing to be neutral to obtain a filter cake; adding water into the filter cake and pulping to obtain the composite microsphere slurry which has the solid content of 40 weight percent and is rich in mesopores and the content of the composite microsphere slurry is 19.5gH₃PO₄(85 wt%) 60g of water is added, and the obtained mixture is mixed with the composite microsphere rich in mesoporesMixing and dipping the slurry, and drying; roasting the obtained sample at 550 ℃ for 2 hours to obtain the catalytic cracking catalyst A provided by the invention. The physicochemical properties of catalyst sample A are shown in Table 1, and the results of ACE evaluation of the feedstock after 100% steam aging at 800 ℃ for 14 hours are shown in Table 2, and the properties of the feedstock for evaluation are shown in Table 3.

Example 2

529.4g of silica sol and 44g of montmorillonite are mixed, decationized water is used for preparing slurry with the solid content of 24 g, the slurry is stirred for 0.5 hour, 132g (calculated by dry basis) of ZRP-1 molecular sieve is added, the mixture is uniformly stirred to form first composition slurry (the solid content is 35 weight percent), spray drying is carried out to prepare composition microspheres, and then the composition microspheres are roasted for 2 hours at 350 ℃ to obtain first composition microspheres B1.

Taking 200g of the prepared first composition microspheres B1 (dry basis weight), adding water to prepare first composition microsphere slurry with the solid content of 10 weight percent, adding 20.5g of NaOH (with the purity of 96 percent), heating to 70 ℃, stirring at constant temperature for 0.3h, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain slurry with the solid content of 10 weight percent, adding 25.1g of oxalic acid while stirring, then adding 120g of hydrochloric acid (HCl with the mass fraction of 10%) and 98g of fluosilicic acid solution (the concentration of fluosilicic acid is 3 weight percent), heating to 80 ℃, stirring at constant temperature for 0.8h, filtering, and washing to obtain a filter cake; adding water into the filter cake and pulping to obtain slurry JY2 with the solid content of 40 wt%; at 1.95gH₃PO₄Adding 90g of water (with the concentration of 85 weight percent), mixing and soaking with the slurry JY2, drying, and roasting at 550 ℃ for 2 hours; namely the catalytic cracking catalyst B provided by the invention. The physicochemical properties of catalyst sample B are shown in Table 1, and the results of the ACE evaluation of the feedstock oil at 14 hours after aging at 800 ℃ in a 100% steam atmosphere are shown in Table 3 for the feedstock oil.

Example 3

Taking 200g of the prepared first composition microspheres B1 (dry basis weight), adding water to prepare first composition microsphere slurry with the solid content of 10 weight percent, adding 33.1g of KOH (purity of 96 percent), heating to 60 ℃, stirring for 1 hour at constant temperature, filtering, and washing to be neutral; adding water into the filter cake, pulping to obtain slurry with solid content of 10 wt%, adding 34 while stirring2g of oxalic acid, slowly adding 235g of hydrochloric acid (HCl mass fraction is 10%) and 97g of fluorosilicic acid solution (concentration is 3 wt%), heating to 70 ℃, stirring for 2 hours at constant temperature, filtering, washing and drying to obtain a dried filter cake; adding water into the dried filter cake and pulping to obtain slurry JY3 with the solid content of 40 wt%; 9.3g (NH)₄)₂HPO₄Dissolving in 180g of water, mixing and soaking with the slurry JY3, and drying; the obtained sample is roasted for 2 hours at 550 ℃, and the catalyst C provided by the invention is obtained. Physicochemical properties of catalyst sample C; after aging at 800 ℃ for 14 hours with 100% steam, stock oils were subjected to ACE evaluation as shown in Table 3, and the evaluation results are shown in Table 2.

Example 4

Taking 200g of the prepared catalyst B1 (dry basis weight), adding water to prepare slurry with the solid content of 10 weight percent, adding 21.2g of NaOH (with the purity of 96 percent), heating to 90 ℃, stirring for 2 hours at constant temperature, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain slurry with the solid content of 10 wt%, adding 5.6g of citric acid while stirring, then adding 247g of hydrochloric acid (the mass fraction of HCl is 10 wt%) and 966.7g of fluorosilicic acid solution (the concentration of fluosilicic acid is 3 wt%), heating to 30 ℃, stirring at constant temperature for 5.5h, filtering, washing and drying to obtain a composition DJ4 rich in mesopores; at 12.8gH₃PO₄(concentration 85%) adding 160g of water, mixing with the composition DJ4 rich in mesopores, soaking, and drying; and roasting the obtained sample at 550 ℃ for 2 hours in an atmosphere of 100% water vapor to obtain the catalytic cracking catalyst D provided by the invention. Physicochemical properties of catalyst sample D; after aging at 800 ℃ and 100% steam for 14 hours, the stock oil ACE evaluation was performed according to the method of example 1, and the evaluation results are shown in Table 2.

Comparative example 1

The basic procedure in this comparative example is as in example 1, except that the sodium is washed by ammonium sulfate solution without alkali and acid treatment, without phosphorus modification, and by ammonium exchange, the sample obtained is comparative sample I. The physicochemical properties are shown in Table 1, and the results of ACE evaluation of the raw oil by the method of example 1 are shown in Table 2.

Comparative example 2

A catalyst was prepared by following the procedure of example 1 except that, in the acid treatment, only an organic acid and an inorganic acid were used without conducting the alkali treatment, and the fluorosilicic acid was replaced with an equimolar amount of hydrochloric acid. The physicochemical properties are shown in Table 1, and the results of ACE evaluation of the raw oil by the method of example 1 are shown in Table 2.

Comparative example 3

The basic procedure in this comparative example follows the procedure of example 1 except that prior to phosphorus modification no treatment with complex acid was used and sodium was washed with ammonium nitrate exchange and the resulting sample was comparative sample III. The physicochemical properties are shown in Table 1, and the results of ACE evaluation of the raw oil by the method of example 1 are shown in Table 2.

Comparative example 4

A catalytic cracking catalyst was prepared by following the procedure of example 1 except that the complex acid treatment was not conducted, the treatment was conducted with fluorosilicic acid and oxalic acid, and the inorganic acid was replaced with an equimolar amount of oxalic acid, to obtain catalyst sample IV. The physicochemical properties are shown in Table 1, and the results of ACE evaluation of the raw oil by the method of example 1 are shown in Table 2.

Comparative example 5

A catalytic cracking catalyst was prepared by following the procedure of example 1 except that the treatment with the complex acid was not conducted and the treatment with hydrochloric acid was conducted. The molar amount of hydrochloric acid (HCl) was equal to the molar amount of the complex acid, and the resulting sample was comparative sample V. The physicochemical properties and the ACE evaluation results of the raw oil are shown in Table 2.

TABLE 1

TABLE 2

TABLE 3

Item	Raw oil
		Density (20 ℃ C.), g/cm³	0.9334
Dioptric light (70 degree)	1.5061
		Four components, m%
Saturated hydrocarbons	55.6
		Aromatic hydrocarbons	30
Glue	14.4
		Asphaltenes	<0.1
Freezing point, DEG C	34
		Metal content, ppm
Ca	3.9
		Fe	1.1
Mg	<0.1
		Na	0.9
Ni	3.1
		Pb	<0.1
V	0.5
		C m％	86.88
H m％	11.94
		S m％	0.7
M% of carbon residue	1.77

As can be seen from Table 2, compared with the contrast agent, the catalyst provided by the invention is used for cracking hydrocarbon oil, the conversion rate is high, and the yield of propylene and BTX (benzene, toluene and xylene) is high.

Claims

1. A catalytic cracking catalyst comprising the following components in weight percent:

A) 5% ~ 65% natural minerals on a dry basis;

B) 10% ~ 60% oxide binder calculated as oxide;

C) 24% ~ 75% on a dry basis of a first molecular sieve which is a MFI structure molecular sieve, and

D) with P₂O₅~ 15% by weight of a phosphorus additive;

the proportion of the mesoporous protonic acid amount of the catalytic cracking catalyst in the total acid amount is 20% ~ 70%.

2. The catalytic cracking catalyst of claim 1, wherein the phosphorus additive is present in an amount of 0.5-6.5 wt% or 2 ~ 5 wt%.

3. The catalytic cracking catalyst of claim 1, having a total specific surface area of 240 ~ 350m²The proportion of mesoporous protonic acid accounting for the total acid amount is 25 percent ~ 50 percent.

4. The catalytic cracking catalyst of claim 1, wherein the catalyst has a mesopore volume of 0.14 ~ 0.35.35 ml/g and a ratio of mesopore volume to total pore volume of 35% ~ 60%.

5. The catalytic cracking catalyst of claim 1, wherein the natural minerals are one or more of kaolin, halloysite, montmorillonite, diatomaceous earth, attapulgite, sepiolite, hydrotalcite, bentonite, and rectorite; the oxide is one or more of silicon oxide, aluminum oxide, zirconium oxide, titanium oxide and amorphous silica-alumina.

6. A method for preparing the catalytic cracking catalyst of claim 1 ~ 5, comprising:

forming first composition microspheres comprising the first molecular sieve, natural minerals and oxide binders, and modifying the first composition microspheres; the modification treatment of the microspheres of the first composition comprises the following steps:

b. b, treating the alkali-treated first composition microspheres obtained in the step a in a composite acid solution consisting of fluosilicic acid, organic acid and inorganic acid, filtering, washing and optionally drying to obtain composition microspheres rich in mesopores; or treating the alkali-treated first composition microspheres obtained in the step a in a composite acid solution consisting of fluosilicic acid, organic acid and inorganic acid, filtering, optionally washing, performing ammonium exchange sodium washing treatment, filtering, optionally washing, and optionally drying to obtain composition microspheres rich in mesopores;

c. introducing a phosphorus additive into the composition microspheres rich in mesopores;

d. roasting at 400-800 deg.c for at least 0.5 hr.

7. The method of claim 6, wherein the catalytic cracking catalyst optionally comprises a second molecular sieve, optionally comprises a promoter component, and the step of forming microspheres of the first composition comprising the first molecular sieve, the natural mineral, and the oxide binder comprises:

mixing the first molecular sieve, the natural mineral substance, the precursor sol of the oxide, the optional second molecular sieve, the optional auxiliary agent component and water, pulping, spray drying and optional roasting.

8. The method for preparing a catalytic cracking catalyst according to claim 6, wherein the alkaline solution in step a comprises alkaline compounds, and the alkaline compounds are one or more of sodium hydroxide, potassium hydroxide, lithium hydroxide, ammonium hydroxide and high-alkali sodium metaaluminate.

9. The method for preparing a catalyst for catalytic cracking of a hydrocarbon according to claim 6, wherein the step a comprises contacting the microspheres of the first composition with an alkaline solution, wherein the alkaline solution comprises an alkaline compound, the weight ratio of the microspheres of the first composition to the alkaline compound is 1 (0.01 ~ 0.35.35) based on the dry weight, and the weight ratio of the microspheres of the first composition to the alkaline compound is (0.01-8978.35)The basic compound is calculated as alkali metal oxide, the basic compound of ammonium hydroxide is calculated as NH₃And (6) counting.

10. The catalytic cracking catalyst production method according to claim 6, wherein in the treatment in step a: the weight ratio of the microspheres of the first composition to water on a dry basis is 1: (5-20), wherein the treatment temperature is between room temperature and 100 ℃, and the treatment time is 0.2-4 hours.

11. The process for preparing a catalytic cracking catalyst according to claim 6, wherein the treating in step a is carried out under conditions such that the weight ratio of the microspheres of the first composition to the basic compound is 1 (0.05 ~ 0.25.25) on a dry basis, the alkali metal basic compound is an alkali metal oxide, and the ammonium hydroxide basic compound is NH₃And (6) counting.

12. The catalytic cracking catalyst preparation method of claim 6, wherein the organic acid in step b is at least one of ethylenediaminetetraacetic acid, oxalic acid, acetic acid, citric acid, and sulfosalicylic acid, and the inorganic acid is at least one of hydrochloric acid, sulfuric acid, and nitric acid.

13. The method for preparing a catalyst for catalytic cracking according to claim 6, wherein the treating in the step b is carried out under conditions such that the weight ratio of the microspheres of the first composition, the fluorosilicic acid, the organic acid and the inorganic acid is 1 (0.003 ~ 0.3.3) to (0.01 ~ 0.55.55) to (0.01 ~ 0.45.45) on a dry basis.

14. The method for preparing a catalyst for catalytic cracking according to claim 6, wherein the treating in the step b is carried out under conditions such that the weight ratio of the microspheres of the first composition, the fluorosilicic acid, the organic acid and the inorganic acid is 1 (0.005 ~ 0.3) to (0.02 ~ 0.3.3) to (0.02 ~ 0.3.3) on a dry basis.

15. The method for preparing a catalytic cracking catalyst according to claim 6, wherein the temperature of the treatment in the step b is 25 to 100 ℃ and the time is 0.5 to 6 hours.

16. The catalytic cracking catalyst preparing method of claim 6, wherein the ammonium exchange sodium wash treatment process of step b includes a step of contacting an ammonium salt solution with the acid-treated first composition microspheres, wherein the ammonium salt is at least one selected from the group consisting of ammonium chloride, ammonium sulfate, ammonium carbonate, ammonium bicarbonate, ammonium acetate and ammonium nitrate.

17. The method for preparing a catalytic cracking catalyst according to claim 6, wherein the step c of introducing the phosphorus additive comprises a step of contacting the mesoporous-rich composition microspheres with a phosphorus-containing compound for impregnation and/or ion exchange.

18. The catalytic cracking catalyst preparation method of claim 17, wherein the phosphorus-containing compound is at least one selected from phosphoric acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate, and ammonium phosphate.

19. The catalytic cracking catalyst preparation method of claim 6, wherein the conditions for the calcination treatment in step d include: the atmosphere of the roasting treatment is air atmosphere, nitrogen atmosphere or water vapor atmosphere or the mixture atmosphere of the above atmospheres; the roasting temperature is 400-800 ℃, and the roasting time is 0.5-8 hours.

20. The process for preparing a catalytic cracking catalyst according to claim 6, wherein the oxide binder precursor is one or more of silica sol, alumina sol, peptized pseudo-boehmite, silica-alumina sol and phosphorus-containing alumina sol.

21. The method for preparing a catalyst for catalytic cracking according to claim 6, wherein the microspheres of the first composition comprise, on a dry basis, 5% ~ 65% of natural mineral content based on the weight of the microspheres of the first composition10 percent ~ percent of oxide binder calculated by oxide and 24 percent ~ percent of first molecular sieve calculated by dry basis, wherein the catalytic cracking catalyst contains P by weight₂O₅0.1% ~ 15% phosphorus additive.

22. The catalytic cracking catalyst preparation method of claim 8, wherein the alkaline solution is at least one selected from the group consisting of a sodium hydroxide solution, a potassium hydroxide solution, a lithium hydroxide solution, an ammonium hydroxide solution, and a high alkali sodium metaaluminate solution.

23. The process for preparing a catalytic cracking catalyst according to claim 11, wherein the treating in the step a is carried out under conditions such that the weight ratio of the microspheres of the first composition to the basic compound is 1 (0.01 ~ 0.15) on a dry weight basis.

24. The method for preparing a catalyst for catalytic cracking according to claim 14, wherein the treating in the step b is carried out under conditions such that the weight ratio of the microspheres of the first composition, the fluorosilicic acid, the organic acid and the inorganic acid is 1 (0.005 ~ 0.17) to (0.015 ~ 0.15) to (0.02 ~ 0.15.15) on a dry basis.

25. The method for preparing a catalyst for catalytic cracking according to claim 14, wherein the treating in the step b is carried out under conditions such that the weight ratio of the microspheres of the first composition, the fluorosilicic acid, the organic acid and the inorganic acid is 1 (0.005 ~ 0.1.1) to (0.02 ~ 0.2.2) to (0.02 ~ 0.15.15) on a dry basis.

26. The process for preparing a catalytic cracking catalyst according to claim 16, wherein the ammonium exchange sodium wash treatment is carried out so that the content of sodium oxide in the resulting catalytic cracking catalyst is not more than 0.2% by weight.

27. The process for producing a catalytic cracking catalyst according to claim 6, wherein the catalytic cracking catalyst contains P₂O₅0.5 ~ 6.5.5 wt% phosphorus additive.

28. The process for producing a catalytic cracking catalyst according to claim 6, wherein the catalytic cracking catalyst contains P₂O₅2 ~ 5 wt% phosphorus additive.

29. A method for producing lower olefins by catalytic cracking of hydrocarbons, comprising the step of bringing a hydrocarbon oil into contact with the catalytic cracking catalyst of claim 1 ~ 5.