CN107971002A

CN107971002A - It is a kind of containing rich in mesoporous assistant for calalytic cracking of Beta molecular sieves and preparation method thereof

Info

Publication number: CN107971002A
Application number: CN201610921659.XA
Authority: CN
Inventors: 陈振宇; 朱玉霞; 周灵萍; 张蔚琳; 田辉平; 刘建强; 罗斌; 罗一斌
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2016-10-21
Filing date: 2016-10-21
Publication date: 2018-05-01
Anticipated expiration: 2036-10-21
Also published as: CN107971002B

Abstract

The invention discloses a kind of containing rich in mesoporous assistant for calalytic cracking of Beta molecular sieves and preparation method thereof, by weight and on the basis of the butt weight of the auxiliary agent, what the auxiliary agent contained the 10 75 weight % in terms of butt is rich in mesoporous Beta molecular sieves, with Al₂O₃、P₂O₅And first 3 30 weight % of the sum of clay butt weight meter the phosphorus aluminium inorganic binder containing the first clay, VIII race's metallic addition of other inorganic binders of in terms of oxide 3 30 weight %, the second clay of the 0 60 weight % in terms of butt and the 0 15 weight % in terms of oxide.The auxiliary agent of the present invention can be improved to the yield of isobutene and propylene applied to catalytic cracking, improve octane number.

Description

Catalytic cracking auxiliary agent containing Beta molecular sieve rich in mesopores and preparation method thereof

Technical Field

The invention relates to a catalytic cracking auxiliary agent containing a Beta molecular sieve rich in mesopores and a preparation method thereof.

Background

The low carbon olefin is an important organic chemical raw material, the worldwide demand for the low carbon olefin is increased year by year, the fluidized catalytic cracking is one of the important processes for producing the low carbon olefin, and for most catalytic cracking devices, the addition of an auxiliary agent is an effective technical way for increasing the yield of the low carbon olefin.

Early patents disclose cracking catalysts or promoters containing β zeolite to increase gasoline octane number and to increase the production of lower olefins and liquefied gases, such as U.S. Pat. Nos. 4,4740292, 4,98846, 4911823 and WO95026533, the β zeolite used in these patents is emphasized by the low sodium hydrogen type zeolite and by the high silica to alumina ratio zeolite β can be synthesized directly or by hydrothermal or acid treatment.

U.S. Pat. No. 4,483,7396 discloses a catalyst comprising β zeolite and Y zeolite and containing a metal ionic compound as a stabilizer to improve the hydrothermal stability and mechanical strength of the catalyst₂(OH)₅Cl]_xOr is Al₃Zr(OH)₉Cl₄The stabilizer may be directly reacted with β zeolite or may be added during the preparation of the catalyst.

US6355591 discloses a catalytic cracking aid comprising 4-20% aluminum phosphate, 1-40% ZSM-5, β and mixtures thereof, 40-90% clay for increasing LPG yield, the aluminum phosphate is prepared by diluting concentrated phosphoric acid in deionized water, adding aluminum powder for dissolution, wherein Al and PO are dissolved₄The molar ratio of aluminum phosphate to kaolin is 1:3, the pH is less than 2.0, the prepared aluminum phosphate and kaolin are mixed uniformly, then mixed into molecular sieve slurry, and finally spray-formed, and the assistant does not contain other binders and other inorganic oxides besides aluminum phosphate from the patent claims.

A process for modifying β molecular sieve includes calcining Na β molecular sieve, removing part of skeleton aluminium by acid, potassium exchange to make the content of zeolite K be 0.5-2.5 wt%, drying, calcining, immersing in the buffer solution of near-neutral P salt including K hydrogen phosphate-K dihydrogen phosphate, P hypophosphite-K hypophosphite and P phosphite-K at ordinary temp for 4-10 hr, washing or not washing to make the content of P on zeolite be 0.01-0.5 wt%, drying and calcining, and features high catalytic activity, high catalytic activity and catalytic activity, and low cost.

Chinese patent CN 1179994A proposes a modification method of β molecular sieve, which uses ammonium ion to exchange Na β molecular sieve on zeolite₂O content less than 0.1 wt%, acid treatment of β molecular sieve to eliminate partial skeleton aluminum and to make its Si/Al ratio greater than 50, mixing the dealuminized β molecular sieve with phosphoric acid or phosphate and stoving to form P on the zeolite₂O₅The amount of the modified β molecular sieve is 2-5 wt%, and finally the modified β molecular sieve is hydrothermally calcined at 650 ℃ for 0.5-4 hours under the steam atmosphere, so that the modified β molecular sieve can obtain higher olefin yield, especially the yield of isoolefin and lower coke yield when used for cracking hydrocarbon.

Chinese patent CN1205249A discloses a modification method of β zeolite, which comprises the steps of mixing synthesized β zeolite raw powder with Al-containing zeolite₂O₃Source, P₂O₅Source, SiO₂Source, H₂O₂And water according to β Zeolite Al₂O₃:P₂O₅:SiO₂:H₂O₂:H₂Mixing O1 (0.001-0.02): (0.01-0.30): (0-0.05): (0-0.10): 1.0-3.0) uniformly, drying, heating to 400-650 deg.C, calcining for 1-5 hr, and exchanging with ammonium ion to Na₂The O content is less than 0.1 wt%, and the method can improve the activity stability of β zeolite and raise its crystallization retention.

Chinese patent CN1616351 discloses a process for preparing phosphorus-containing β zeolite, which comprises preparing a working solution from an aluminum source, an alkali source and a tetraethylammonium cation solution in water, using silica gel with a particle size of 20-300 meshes as a silicon source, mixing the silica gel with the working solution to wet the surface of the silica gel particles with the working solution, maintaining the mixture at 80-140 ℃ for 20-80 hours to obtain a seed crystal gel, adding aluminum phosphate with a weight of 5-30% of the seed crystal gel charge into the prepared seed crystal gel, uniformly mixing, crystallizing at 140-170 ℃ for 50-100 hours, separating out a solid product, washing until Na is obtained₂The content of O is less than 0.1 wt%, and the obtained product can be dried, and the β zeolite with phosphorus content as high as 5 wt% can be prepared by said method, and when it is used in alkylation reaction, it has higher catalytic selectivity.

Chinese patent CN1872685A discloses a modified β molecular sieve, which is characterized in that the anhydrous chemical expression of the β molecular sieve is (0-0.3) Na in terms of the mass of oxides₂O·(0.5-10)Al₂O₃·(1.3-10)P₂O₅·(0.7-15)M_xO_y·(70-97)SiO₂Wherein M is selected from one of Fe, Co, Ni, Cu, Mn, Zn and Sn. The zeolite can be used as an active component of a catalyst or an auxiliary agent in catalytic cracking.

Chinese patent CN101434401A discloses a β molecular sieve containing phosphorus, which is characterized in that the phosphorus content of the β molecular sieve is P₂O₅The weight loss is 0.01-10 wt%, and a weight loss peak appears at 220 +/-25 ℃ in a thermogravimetric characterization map, wherein the molecular sieve is obtained by roasting β molecular sieve in an air atmosphere to remove an organic template agent and then treating with a phosphorus compound aqueous solution at 100-250 ℃.

Chinese patent CN101450318A discloses a modification method of β molecular sieve, which is characterized in that a sodium type β molecular sieve is prepared according to the following steps of preparing the molecular sieve from ammonium salt H₂Exchanging the components (0.1-1) and (5-10) at room temperature to 100 ℃ for 0.3-1 h, filtering, impregnating the molecular sieve with a phosphorus compound-containing solution and a metal compound-containing solution, adjusting the pH of the impregnating solution to 6-8, drying, roasting, and modifying。

Chinese patents CN102971065A and CN105312081A disclose a method for NO_xReduced novel metal-containing zeolite β the preparation of which does not require an organic Structure Directing Agent (SDA) the metal may comprise from 1 to 10 wt% Fe or Cu. also discloses a method of selective catalytic reduction of nitrogen oxides in exhaust gases using the disclosed zeolite.

Chinese patent CN103447068A discloses a catalytic cracking catalyst promoter containing β zeolite and application thereof, and relates to a β zeolite catalyst promoter which is suitable for catalytic cracking reaction and can increase liquid yield, reduce coke and increase propylene yield, the catalyst promoter is prepared by modifying, demoulding and aging kaolin microsphere in-situ crystallized β zeolite, and is applied to catalytic cracking reaction, the in-situ crystallized microspheric β zeolite catalyst promoter replaces 2-50 wt% of base catalyst, and compared with β zeolite catalyst promoter prepared by a binder method, the β zeolite promoter prepared by the in-situ crystallization method has stronger propylene yield increase, coking resistance and liquid yield increase capability.

Chinese patent CN103771437A discloses a modified β molecular sieve containing phosphorus, which is characterized in that P is used as a P-containing material₂O₅The content of phosphorus is 3-10 wt%, and the molecular sieve is prepared by²⁷In the Al MAS NMR, the ratio of the area of the resonance signal peak at a chemical shift of 40. + -.3 ppm to the area of the resonance signal peak at a chemical shift of 54 ppm. + -.3 ppm is 1 or more. The molecular sieve has the advantages that the coordination of phosphorus and framework aluminum is sufficient, the framework aluminum is sufficiently protected, and the molecular sieve has excellent hydrothermal stability and better product selectivity.

Chinese patent CN103785455A discloses a cracking assistant for increasing the concentration of catalytically cracked low-carbon olefins, which comprises 10-75 wt% of phosphorus and transition metal modified β molecular sieve, 0-60 wt% of clay, 15-60 wt% of inorganic oxide binder, 0.5-15 wt% of VIII group metal additive and 2-25 wt% of phosphorus additive, wherein the transition metal is selected from one or more of Fe, Co, Ni, Cu, Mn, Zn, Sn and Bi, and the phosphorus and transition metal containing β molecular sieve is prepared by mixing P with P₂O₅The content of phosphorus is calculated as 1-10% by weight of a metal content, calculated as metal oxide, of 0.5 to 10% by weight, of the molecular sieve²⁷In Al MASNMR, the ratio of the resonance signal peak area with a chemical shift of 40 + -3 ppm to the resonance signal peak area with a chemical shift of 54ppm + -3 ppm is greater than 1, and the percentage of the total peak area occupied by the sum of the resonance signal peak areas with a chemical shift of 0 + -3 ppm and a chemical shift of-12 ppm + -3 ppm is less than 10%. The cracking catalyst composition is applied to the catalytic cracking of petroleum hydrocarbon, can increase the yield of catalytic cracking liquefied gas, improve the concentration of low-carbon olefin in the liquefied gas, particularly the concentration of isobutene, and simultaneously improve the ratio of ethylene to dry gas and the octane number of gasoline.

Chinese patent CN103785456A discloses a cracking assistant for increasing the concentration of low-carbon olefin, which contains modified β molecular sieve, phosphor-aluminum inorganic binder containing first clay, other inorganic binders and VIII-group metal additive, with or without second clay, wherein the phosphor-aluminum inorganic binder containing first clay comprises aluminum component, phosphorus component and first clay, the phosphorus and transition metal modified β molecular sieve is P₂O₅The phosphorus content is 1-10 wt%, the metal content is 0.5-10 wt%, calculated by metal oxide, the molecular sieve is prepared by²⁷In the Al MAS NMR, the ratio of the area of a resonance signal peak having a chemical shift of 40. + -.3 ppm to the area of a resonance signal peak having a chemical shift of 54. + -.3 ppm is 1 or more, and the percentage of the total area of the areas of resonance signal peaks having a chemical shift of 0. + -.3 ppm and a chemical shift of-12. + -.3 ppm is 10% or less. The cracking catalyst composition is applied to the catalytic cracking of petroleum hydrocarbon, can increase the yield of catalytic cracking liquefied gas, improve the concentration of low-carbon olefin in the liquefied gas, especially the concentration of isobutene, simultaneously improve the ratio of ethylene to dry gas, improve the octane number of gasoline, and does not influence the heavy oil conversion capability of a main catalyst when being mixed with an auxiliary agent in a large proportion.

Chinese patent CN103785457A discloses a cracking assistant for increasing the concentration of low-carbon olefin, which comprises 10-75 wt% of β molecular sieve containing phosphorus and transition metal, 0-60 wt% of clay and 15-60 wt% of inorganic oxide binder, wherein P is used as the raw material in the β molecular sieve containing phosphorus and transition metal₂O₅Phosphorus content of 1-10 wt%, metal content of 0.5-10 wt%, calculated as metal oxide, of β molecular sieve containing phosphorus and transition metal²⁷In the Al MAS NMR, the ratio of the area of the resonance signal peak with a chemical shift of 40. + -.3 ppm to the area of the resonance signal peak with a chemical shift of 54. + -.3 ppm is more than 1, and the percentage of the sum of the areas of the resonance signal peaks with a chemical shift of 0. + -.3 ppm and a chemical shift of-12. + -.3 ppm in the total peak area is less than 10%. The assistant is applied to catalytic cracking, and can improve the concentration of ethylene in catalytic cracking dry gas and the concentration of propylene and isobutene in liquefied gas.

Chinese patent CN103785458A discloses a cracking assistant for increasing the concentration of low-carbon olefin, which contains a phosphorus-aluminum inorganic binder containing phosphorus and transition metal and containing first clay, other inorganic binders and second clay; wherein the first clay-containing phosphorus-aluminum inorganic binder comprises Al₂O₃15 to 40 wt.% of an aluminum component in terms of P₂O₅45-80 wt% of phosphorus component and 1-40 wt% of first clay calculated by dry basis, wherein the weight ratio of P/Al is 1-6, and the β molecular sieve containing phosphorus and transition metal is calculated as P₂O₅The content of phosphorus is 1-10 wt%, the content of metal is 0.5-10 wt%, and the molecular sieve is prepared from phosphorus, metal oxide and inorganic salt²⁷In the Al MAS NMR, the ratio of the area of the resonance signal peak with a chemical shift of 40. + -.3 ppm to the area of the resonance signal peak with a chemical shift of 54. + -.3 ppm is more than 1, and the percentage of the sum of the areas of the resonance signal peaks with a chemical shift of 0. + -.3 ppm and a chemical shift of-12. + -.3 ppm in the total peak area is less than 10%. The auxiliary agent is applied to catalytic cracking, and can improve the ethylene concentration in catalytic cracking dry gas and the propylene and isobutene concentrations in liquefied gas.

Chinese patent CN103787357A discloses a modified β molecular sieve which is P₂O₅The phosphorus content is 1-10 wt.%, the metal content is 0.5-10 wt.% in terms of metal oxide, characterized in that the molecular sieve has²⁷In Al MAS NMR, the ratio of the area of the resonance signal peak with a chemical shift of 40. + -.3 ppm to the area of the resonance signal peak with a chemical shift of 54. + -.3 ppm is 1 or more, and the chemical shift is 0. + -.3 ppm and the chemical shift is-12. + -.3 ppmThe percentage of the sum of the resonance signal peak areas in the total peak area is 10% or less. The molecular sieve has excellent hydrothermal stability, and has better product selectivity when being used as an active component of a catalyst or an auxiliary agent in a catalytic cracking or catalytic cracking process.

Chinese patent CN103787358A discloses a β molecular sieve containing phosphorus and metal, which is characterized in that P is used as a P-containing zeolite₂O₅The phosphorus content is 1-10 wt%, the metal content is 0.5-10 wt%, calculated by metal oxide, the molecular sieve is prepared by²⁷In the Al MAS NMR, the ratio of the area of the resonance signal peak at a chemical shift of 40. + -.3 ppm to the area of the resonance signal peak at a chemical shift of 54 ppm. + -.3 ppm is 1 or more.

Chinese patent CN103787359A discloses a phosphorus-containing silicon-rich β molecular sieve, which is characterized in that P is used as a P-containing silicon-rich molecular sieve₂O₅The phosphorus content is 1-10 wt%, and the molecular sieve has²⁷In Al MAS NMR, the ratio of the resonance signal peak area with a chemical shift of 40 plus or minus 3ppm to the resonance signal peak area with a chemical shift of 54ppm plus or minus 3ppm is greater than or equal to 1, and the percentage of the sum of the resonance signal peak areas with a chemical shift of 0 plus or minus 3ppm to the total peak area is less than or equal to 10%.

β molecular sieve has unique channel structure, high acidity and excellent hydrothermal stability, and has wide industrial application foreground, and it has been used in isomerization, catalytic cracking, arene alkylation and other petrochemical fields.

Chinese patents CN104418345A, CN104418346A, CN104418347A, CN104418348A, CN104418349A, CN104418350A, CN104418351A, CN104418352A and CN104418353A disclose a group of molecular sieves with a multistage pore structure β and a preparation method thereof, wherein high molecular polymers such as polyquaternium-6, polyquaternium-7, polyquaternium-10, polyquaternium-11, polyquaternium-22, polyquaternium-32, polyquaternium-37, polyquaternium-39, polyquaternium-44 and the like are adopted as guiding agents of micropores and mesopores in the synthesis process, and the synthesized β molecular sieve has mesopores of 8-20 nm and macropores of 50-200 nm at the same time.

Chinese patent CN105692644A discloses a method for preparing hierarchical pore zeolite, namely, various alkali vapors are used as mineralizers for zeolitization, amorphous mesoporous/macroporous materials are used as precursors, and the hierarchical pore zeolite materials are prepared by an alkali vapor heat treatment method.

The methods for preparing the hierarchical pores β all have the problems that organic ammonium salt sewage is not easy to treat, the preparation process is long, the molecular sieve pore structure is damaged, the surface aluminum distribution is not modulated, and the like.

Disclosure of Invention

The invention aims to provide a catalytic cracking auxiliary agent containing a Beta molecular sieve rich in mesopores and a preparation method thereof.

In order to achieve the above object, the present invention provides a catalytic cracking aid containing a mesoporous-rich Beta molecular sieve, wherein the catalytic cracking aid is used in combination of weightThe auxiliary agent contains 10-75 wt% of Beta molecular sieve rich in mesopores on a dry basis, based on the dry basis weight of the agent, and the Beta molecular sieve is Al₂O₃、P₂O₅And 3-30 wt% of a first clay-containing aluminophosphate inorganic binder, based on the sum of the dry weights of the first clays, 3-30 wt% of other inorganic binders, based on oxides, 0-60 wt% of a second clay, based on dry weights, and 0-15 wt% of a group VIII metal additive, based on oxides; wherein the first clay-containing phosphorus aluminum inorganic binder comprises Al based on the dry weight of the first clay-containing phosphorus aluminum inorganic binder₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and 1-40 wt% of first clay calculated by dry weight, wherein the weight ratio of P/Al is 1.0-6.0, the pH value is 1-3.5, and the solid content is 15-60 wt%; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.4 and less than or equal to 0.8, wherein D is Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the inward H distance of the crystal face edge of the molecular sieve crystal grain measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the outward H distance of the geometric center of the crystal face of the molecular sieve crystal grain measured by the TEM-EDS method, wherein H is 10 percent of the distance from a certain point of the crystal face edge to the geometric center of the crystal face; the specific surface area of the micropores of the molecular sieve is 350-500 m²The proportion of the mesoporous volume of the molecular sieve in the total pore volume is 30-70% by volume.

Preferably, the molecular sieve has an Al distribution parameter D that satisfies: d is more than or equal to 0.55 and less than or equal to 0.75; the specific surface area of the micropores of the molecular sieve is 370-450 m²And/g, the proportion of the mesoporous volume of the molecular sieve in the total pore volume is 35-60% by volume.

Preferably, the first clay is at least one selected from kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomite; the second clay is at least one selected from kaolin, metakaolin, diatomite, sepiolite, attapulgite, montmorillonite and rectorite; the inorganic oxide binder includes at least one selected from the group consisting of pseudoboehmite, alumina sol, silica-alumina sol, and water glass.

Preferably, the auxiliary agent also contains P based on the dry weight of the auxiliary agent₂O₅Up to 25 wt% of a phosphorus additive.

Preferably, the auxiliary agent contains 20-60 wt% of Beta molecular sieve rich in mesopores on a dry basis, calculated by weight and based on the dry basis weight of the auxiliary agent, and calculated by Al₂O₃、P₂O₅And 8-25 wt% of a phosphorus-aluminum inorganic binder containing the first clay calculated by the sum of the dry weight of the first clay, 5-25 wt% of other inorganic binders calculated by oxides, 10-45 wt% of a second clay calculated by the dry weight, and P₂O₅0-10% by weight of a phosphorus additive and 1-10% by weight of a group VIII metal additive, calculated as the oxide.

Preferably, the phosphorus additive is introduced to the adjuvant in the form of a phosphorus-containing compound comprising at least one selected from the group consisting of oxides, phosphates, phosphites, basic phosphates and acid phosphates of phosphorus; the group VIII metal comprises at least one selected from Fe, Co and Ni, and the group VIII metal additive is introduced to the promoter in the form of a metal-containing compound comprising at least one selected from the group consisting of oxides, hydroxides, chlorides, nitrates, sulfates, phosphates and organic compounds.

Preferably, the preparation step of the first clay-containing aluminophosphate inorganic binder comprises: (1) pulping and dispersing an alumina source, first clay and water into slurry with the solid content of 8-45 wt%; the alumina source is aluminum hydroxide and/or aluminum oxide which can be peptized by acid, first clay and Al which are calculated by dry weight₂O₃The weight ratio of the alumina source is (1-40) to (15-40); (2) adding concentrated phosphoric acid into the slurry obtained in the step (1) according to the weight ratio of P/Al to 1-6 under stirring; (3) and (3) reacting the slurry obtained in the step (2) at the temperature of 50-99 ℃ for 15-90 minutes.

The invention also providesA preparation method of a catalytic cracking assistant is provided, which comprises the following steps: mixing the Beta molecular sieve rich in mesopores, the phosphorus-aluminum inorganic binder containing the first clay and water, adding or not adding the second clay, pulping, and spray-drying; wherein, a phosphorus additive is introduced or not introduced, and a group VIII metal additive is introduced or not introduced; based on the weight and the dry basis weight of the preparation raw materials of the auxiliary agent, the preparation raw materials of the auxiliary agent contain 10-75 wt% of Beta molecular sieve rich in mesopores on the dry basis, and the Beta molecular sieve is calculated by Al₂O₃、P₂O₅And 3-30 wt% of a phosphorus-aluminum inorganic binder containing the first clay calculated by the sum of the dry weight of the first clay, 3-30 wt% of other inorganic binders calculated by oxides, 0-60 wt% of a second clay calculated by the dry weight, and P₂O₅Up to 25 wt.% of a phosphorus additive and 0-15 wt.% of a group VIII metal additive, calculated as the oxide; the first clay-containing phosphorus aluminum inorganic binder comprises Al based on the dry weight of the first clay-containing phosphorus aluminum inorganic binder₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and 1-40 wt% of first clay calculated by dry weight, wherein the weight ratio of P/Al is 1.0-6.0, the pH value is 1-3.5, and the solid content is 15-60 wt%; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.4 and less than or equal to 0.8, wherein D is Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the inward H distance of the crystal face edge of the molecular sieve crystal grain measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the outward H distance of the geometric center of the crystal face of the molecular sieve crystal grain measured by the TEM-EDS method, wherein H is 10 percent of the distance from a certain point of the crystal face edge to the geometric center of the crystal face; the specific surface area of the micropores of the molecular sieve is 350-500 m²The proportion of the mesoporous volume of the molecular sieve in the total pore volume is 30-70% by volume.

Preferably, the preparation step of the mesoporous-rich Beta molecular sieve comprises the following steps: a. carrying out alkali treatment on the sodium type Beta molecular sieve in an alkaline solution, and filtering and washing to obtain an alkali-treated molecular sieve; b. and (b) dealuminizing the alkali-treated molecular sieve obtained in the step a in a composite acid dealuminating agent solution consisting of fluosilicic acid, organic acid and inorganic acid, and filtering and washing to obtain the Beta molecular sieve rich in mesopores.

Preferably, 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, ammonia water and an overbased sodium metaaluminate solution; the sodium content of the high-alkali sodium metaaluminate solution is 270-310 g/L, the aluminum content is 30-50 g/L and the density of the high-alkali sodium metaaluminate solution is 1.25-1.45 g/mL.

Preferably, the conditions of the alkali treatment in step a include: the weight ratio of the molecular sieve to the alkali in the alkaline solution on a dry basis is 1: (0.02-0.3); wherein the weight of the alkali in the sodium hydroxide solution is based on the weight of sodium hydroxide, the weight of the alkali in the potassium hydroxide solution is based on the weight of potassium hydroxide, the weight of the alkali in the lithium hydroxide solution is based on the weight of lithium hydroxide, the weight of the alkali in the ammonia water is based on the weight of ammonia monohydrate, and the weight of the alkali in the high-alkali sodium metaaluminate solution is based on the weight of sodium oxide.

Preferably, the conditions of the alkali treatment in step a include: the temperature of alkali treatment is 25-100 ℃, and the time of alkali treatment is 0.5-6 hours.

Preferably, the organic acid in step b is at least one selected from the group consisting of ethylenediaminetetraacetic acid, oxalic acid, citric acid and sulfosalicylic acid, and the inorganic acid is at least one selected from the group consisting of hydrochloric acid, sulfuric acid and nitric acid.

Preferably, the dealumination treatment conditions in step b include: the weight ratio of the molecular sieve, the fluosilicic acid, the organic acid and the inorganic acid is 1: (0.03-0.5): (0.05-0.4): 0.05-0.5); the treatment temperature is 25-100 ℃, and the treatment time is 0.5-6 hours.

Preferably, the dealumination treatment conditions in step b include: the weight ratio of the molecular sieve, the fluosilicic acid, the organic acid and the inorganic acid is 1: (0.05-0.3):(0.1-0.3):(0.1-0.3).

The cracking assistant provided by the invention adopts β molecular sieve rich in mesopores as an active component, and can also introduce a proper amount of phosphorus additive and VIII metal additive, thereby improving the yield and selectivity of isobutene, propylene and ethylene, improving the octane number of catalytic cracking gasoline, and increasing the liquid yield of catalytic cracking reaction.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Detailed Description

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 invention provides a catalytic cracking auxiliary agent containing a Beta molecular sieve rich in mesopores, which comprises the Beta molecular sieve rich in mesopores in an amount of 10-75 wt% on a dry basis by weight based on the dry weight of the auxiliary agent, wherein Al is used₂O₃、P₂O₅And 3-30 wt% of a first clay-containing aluminophosphate inorganic binder, based on the sum of the dry weights of the first clays, 3-30 wt% of other inorganic binders, based on oxides, 0-60 wt% of a second clay, based on dry weights, and 0-15 wt% of a group VIII metal additive, based on oxides; wherein the first clay-containing phosphorus aluminum inorganic binder comprises Al based on the dry weight of the first clay-containing phosphorus aluminum inorganic binder₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and 1-40 wt% of first clay calculated by dry weight, wherein the weight ratio of P/Al is 1.0-6.0, the pH value is 1-3.5, and the solid content is 15-60 wt%; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.4 and less than or equal to 0.8, wherein D is Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the inward H distance of the crystal face edge of the molecular sieve crystal grain measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the outward H distance of the geometric center of the crystal face of the molecular sieve crystal grain measured by the TEM-EDS method, wherein H is 10 percent of the distance from a certain point of the crystal face edge to the geometric center of the crystal face; the specific surface area of the micropores of the molecular sieve is 350-500 m²The proportion of the mesoporous volume of the molecular sieve in the total pore volume is 30-70% by volume. Preferably, the divisionThe Al distribution parameter D of the sub-sieve meets the following requirements: d is more than or equal to 0.55 and less than or equal to 0.75; the specific surface area of the micropores of the molecular sieve is 370-450 m²And/g, the proportion of the mesoporous volume of the molecular sieve in the total pore volume is 35-60% by volume.

According to the present invention, the clay is well known to those skilled in the art, and the first clay may be at least one selected from kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomite, preferably comprises rectorite, more preferably rectorite; the second clay may be at least one selected from kaolin, metakaolin, sepiolite, attapulgite, montmorillonite, rectorite, diatomaceous earth, halloysite, saponite, bentonite and hydrotalcite, preferably at least one selected from kaolin, metakaolin, diatomaceous earth, sepiolite, attapulgite, montmorillonite and rectorite; the additional inorganic binder may be selected from one or more of the inorganic oxide binders conventionally used in catalytic cracking promoters or catalyst binder components other than the first clay-containing aluminophosphate inorganic binder, preferably from at least one of pseudoboehmite, alumina sol, silica alumina sol, and water glass, more preferably from at least one of pseudoboehmite and alumina sol.

According to the invention, the first clay-containing aluminophosphate inorganic binder preferably contains Al₂O₃15-35% by weight, calculated as P, of an aluminium component₂O₅A phosphorus component in an amount of 50 to 75 wt% and a first clay in an amount of 8 to 35 wt% on a dry basis, preferably having a P/Al weight ratio of 1.2 to 6.0, more preferably 2.0 to 5.0, and a pH value of 1.0 to 3.5.

According to the invention, the auxiliary agent may also contain P based on the dry weight of the auxiliary agent₂O₅Up to 25 wt% of a phosphorus additive. The phosphorus additive may be introduced into the adjuvant in the form of a phosphorus compound, such as one or more of inorganic and organic compounds including phosphorus, which may be readily soluble in water, or a poorly water-soluble or water-insoluble phosphorus compound, such as an oxide of phosphorus, phosphoric acid, orthophosphate, phosphite, hypophosphite, or a combination thereofOne or more of a basic phosphate, an acid phosphate, and a phosphorus-containing organic compound. Preferred phosphorus compounds are one or more of phosphoric acid, ammonium phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate and aluminum phosphate. The resulting adjuvant has a phosphorus additive in the form of a phosphorus compound such as phosphorus oxide, orthophosphate, phosphite, basic phosphate and acid phosphate. The phosphorus additive may be present in any location where a promoter may be present, such as inside the channels of the zeolite, on the surface of the zeolite, in the matrix material (i.e., a material other than the molecular sieve in the promoter), and also both inside the channels of the zeolite, on the surface of the zeolite, and in the matrix material. The phosphorus additive is not included in the content of phosphorus in the molecular sieve, nor is the phosphorus introduced by the phosphorus-aluminum inorganic binder included.

According to the invention, the metal additive may be added during the beating process, which may be introduced in the form of the metal compound in the preparation of the shaped aid, for example in the form of at least one selected from the group consisting of oxides, hydroxides, chlorides, nitrates, sulfates, phosphates and organic compounds, preferably in the form of one or more from the group consisting of oxides, orthophosphates, phosphites, basic phosphates and acid phosphates.

According to the present invention, it is well known to those skilled in the art to determine the aluminum content of the molecular sieve by using the TEM-EDS method, wherein the geometric center is also well known to those skilled in the art, and can be calculated according to a formula, which is not repeated in the present invention, and the geometric center of the general symmetric figure is the intersection point of the connection lines of the relative vertexes, for example, the geometric center of the square crystal face of the conventional cubic Beta molecular sieve is at the intersection point of the connection lines of the relative vertexes. The crystal plane is a plane of regular crystal grains, and the inward and outward directions are both inward and outward directions on the crystal plane.

According to the invention, the proportion of the micropore specific surface area and the mesopore volume of the molecular sieve in the total pore volume is measured by a nitrogen adsorption BET specific surface area method, and the mesopore volume refers to the pore volume with the pore diameter of more than 2 nanometers and less than 100 nanometers.

The invention also provides a preparation method of the catalytic cracking assistant, which comprises the following steps: mixing the Beta molecular sieve rich in mesopores, the phosphorus-aluminum inorganic binder containing the first clay and water, adding or not adding the second clay, pulping, and spray-drying; wherein, a phosphorus additive is introduced or not introduced, and a group VIII metal additive is introduced or not introduced; based on the weight and the dry basis weight of the preparation raw materials of the auxiliary agent, the preparation raw materials of the auxiliary agent contain 10-75 wt% of Beta molecular sieve rich in mesopores on the dry basis, and the Beta molecular sieve is calculated by Al₂O₃、P₂O₅And 3-30 wt% of a phosphorus-aluminum inorganic binder containing the first clay calculated by the sum of the dry weight of the first clay, 3-30 wt% of other inorganic binders calculated by oxides, 0-60 wt% of a second clay calculated by the dry weight, and P₂O₅Up to 25 wt.% of a phosphorus additive and 0-15 wt.% of a group VIII metal additive, calculated as the oxide; the first clay-containing phosphorus aluminum inorganic binder comprises Al based on the dry weight of the first clay-containing phosphorus aluminum inorganic binder₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and 1-40 wt% of first clay calculated by dry weight, wherein the weight ratio of P/Al is 1.0-6.0, the pH value is 1-3.5, and the solid content is 15-60 wt%; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.4 and less than or equal to 0.8, wherein D is Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the inward H distance of the crystal face edge of the molecular sieve crystal grain measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the outward H distance of the geometric center of the crystal face of the molecular sieve crystal grain measured by the TEM-EDS method, wherein H is 10 percent of the distance from a certain point of the crystal face edge to the geometric center of the crystal face; the specific surface area of the micropores of the molecular sieve is 350-500 m²The proportion of the mesoporous volume of the molecular sieve in the total pore volume is 30-70% by volume.

According to the present invention, the preparation steps of the mesoporous enriched Beta molecular sieve may include: a. carrying out alkali treatment on the sodium type Beta molecular sieve in an alkaline solution, and filtering and washing to obtain an alkali-treated molecular sieve; b. and (b) dealuminizing the alkali-treated molecular sieve obtained in the step a in a composite acid dealuminating agent solution consisting of fluosilicic acid, organic acid and inorganic acid, and filtering and washing to obtain the Beta molecular sieve rich in mesopores.

According to the present invention, the sodium type Beta molecular sieve is well known to those skilled in the art, and can be obtained by amine-free crystallization or calcination of a molecular sieve prepared by a template method, specifically, see U.S. Pat. No. 3,308,069 and chinese patent CN 00107486.5, and the sodium content in the sodium type Beta molecular sieve can be 4-6 wt% calculated as sodium oxide.

According to the invention, the alkali treatment is used for removing part of framework silicon atoms of the molecular sieve to generate more secondary pores, and the alkaline solution can be at least one selected from sodium hydroxide solution, potassium hydroxide solution, lithium hydroxide solution, ammonia water and high-alkali sodium metaaluminate solution, and is preferably high-alkali sodium metaaluminate solution; the sodium content of the high-alkali sodium metaaluminate solution can be 270-310 g/L, the aluminum content can be 30-50 g/L and the density of the high-alkali sodium metaaluminate solution can be 1.25-1.45 g/mL calculated by oxide; the conditions of the alkali treatment in step a may include: the weight ratio of the molecular sieve to the base in the alkaline solution on a dry weight basis may be 1: (0.02-0.3), preferably 1: (0.03-0.25); wherein the weight of the alkali in the sodium hydroxide solution is based on the weight of sodium hydroxide, the weight of the alkali in the potassium hydroxide solution is based on the weight of potassium hydroxide, the weight of the alkali in the lithium hydroxide solution is based on the weight of lithium hydroxide, the weight of the alkali in the ammonia water is based on the weight of ammonia monohydrate, and the weight of the alkali in the high-alkali sodium metaaluminate solution is based on the weight of sodium oxide; the temperature of the alkali treatment can be 25-100 ℃, and the time of the alkali treatment can be 0.5-6 hours.

The dealumination treatment according to the present invention is well known to those skilled in the art, but the use of an inorganic acid, an organic acid and a fluosilicic acid together for the dealumination treatment has not been reported. The dealumination treatment can be carried out once or for multiple times, organic acid can be firstly mixed with the alkali treatment molecular sieve, and then fluosilicic acid and inorganic acid are mixed with the alkali treatment molecular sieve, namely, the organic acid is firstly added into the alkali treatment molecular sieve, and then the fluosilicic acid and the inorganic acid are slowly and concurrently added, or the fluosilicic acid is firstly added and then the inorganic acid is added, preferably the fluosilicic acid and the inorganic acid are slowly and concurrently added. The organic acid in step b may be at least one selected from ethylenediaminetetraacetic acid, oxalic acid, citric acid and sulfosalicylic acid, preferably oxalic acid or citric acid, and more preferably oxalic acid; the inorganic acid may be at least one selected from hydrochloric acid, sulfuric acid and nitric acid, preferably hydrochloric acid or sulfuric acid, and more preferably hydrochloric acid; the dealumination treatment conditions in step b may include: the weight ratio of the molecular sieve, the fluosilicic acid, the organic acid and the inorganic acid on a dry basis weight basis may be 1: (0.03-0.5): (0.05-0.4): 0.05-0.5), preferably 1: (0.05-0.3): (0.1-0.3): 0.1-0.3); the treatment temperature may be 25-100 deg.C and the treatment time may be 0.5-6 hr.

The washing according to the invention is well known to the person skilled in the art and is generally referred to as water washing, for example, the molecular sieve may be rinsed with water at 30-60 ℃ in an amount of 5-10 times the weight of the molecular sieve.

According to the present invention, the preparation step of the first clay-containing aluminophosphate inorganic binder may include: (1) pulping and dispersing an alumina source, first clay and water into slurry with the solid content of 8-45 wt%; the alumina source is aluminum hydroxide and/or aluminum oxide which can be peptized by acid, first clay and Al which are calculated by dry weight₂O₃The weight ratio of the alumina source is (1-40) to (15-40); (2) adding concentrated phosphoric acid into the slurry obtained in the step (1) according to the weight ratio of P/Al to 1-6 under stirring; wherein P in the P/Al is the weight of phosphorus in the phosphoric acid by simple substance, and Al is the weight of aluminum in the alumina source by simple substance; (3) and (3) reacting the slurry obtained in the step (2) at the temperature of 50-99 ℃ for 15-90 minutes.

According to the present invention, the alumina source may be at least one selected from the group consisting of rho-alumina, chi-alumina, η -alumina, gamma-alumina, kappa-alumina, delta-alumina, theta-alumina, gibbsite, surge, nordstrandite, diaspore, boehmite, and pseudoboehmite, the aluminum component of the first clay-containing aluminophosphate inorganic binder is derived from the alumina source, the first clay may be one or more selected from the group consisting of kaolin, sepiolite, attapulgite, rectorite, montmorillonite, and diatomaceous earth, preferably rectorite, the concentrated phosphoric acid may have a concentration of 60 to 98 wt%, more preferably 75 to 90 wt%, the feeding rate of phosphoric acid is preferably 0.01 to 0.10Kg of phosphoric acid per minute per Kg of alumina source, more preferably 0.03 to 0.07Kg of phosphoric acid per minute per Kg of alumina source.

According to the invention, due to the introduction of the clay, the phosphorus-aluminum inorganic binder containing the first clay not only improves mass transfer and heat transfer among materials in the preparation process, but also avoids the binder solidification caused by nonuniform local instant violent reaction, heat release and overtemperature, and the bonding performance of the obtained binder is equivalent to that of the phosphorus-aluminum binder prepared by a method without introducing the clay; in addition, the method introduces clay, especially rectorite with a layered structure, improves the heavy oil conversion capability of the catalyst composition, and enables the obtained auxiliary agent to have better selectivity.

The preparation method of the catalytic cracking assistant provided by the invention mixes and pulps the Beta molecular sieve, the phosphorus-aluminum inorganic binder containing the first clay and other inorganic binders, and the feeding sequence of the Beta molecular sieve, the phosphorus-aluminum inorganic binder containing the first clay, other inorganic binders, the molecular sieve and the second clay are not particularly required, for example, the phosphorus-aluminum inorganic binder containing the first clay, other inorganic binders, the molecular sieve and the second clay can be mixed and pulped (when the second clay is not contained, the relevant feeding step can be omitted), preferably, the phosphorus-aluminum inorganic binder is added after the second clay, the molecular sieve and other inorganic binders are mixed and pulped, which is favorable for improving the activity and selectivity of the assistant.

The preparation method of the catalytic cracking assistant also comprises the step of spray drying the slurry obtained by pulping. Spray drying methods are well known to those skilled in the art and there is no particular requirement for the present invention.

In the preparation method of the catalytic cracking assistant provided by the invention, the metal additive can be introduced in the form of a metal compound, and the metal additive can be introduced by adding the metal compound into slurry in any step before spray drying and forming in the preparation process of the assistant; or the promoter can be introduced by impregnating or chemically adsorbing the metal compound and then roasting after spray drying and molding, including the steps of impregnating or chemically adsorbing the promoter by using the aqueous solution of the metal-containing compound, and then carrying out solid-liquid separation (if needed), drying and roasting, wherein the drying temperature can be between room temperature and 400 ℃, preferably 100-300 ℃, the roasting temperature can be between 400-700 ℃, preferably 450-650 ℃, and the roasting time can be between 0.5 and 100 hours, preferably between 0.5 and 10 hours. The metal compound is selected from one or more of inorganic compounds and organic compounds thereof, and can be easily soluble in water, or can be hardly soluble in water or insoluble in water. Examples of the metal compound include oxides, hydroxides, chlorides, nitrates, sulfates, phosphates, organic compounds of metals, and the like of metals. Preferred metal compounds are selected from one or more of their chlorides, nitrates, sulfates and phosphates.

In the catalytic cracking assistant provided by the invention, the metal additive can be present in any possible position of the assistant, such as the inside of the pore channel of the zeolite, the surface of the zeolite, the matrix material, or both the inside of the pore channel of the zeolite, the surface of the zeolite and the matrix material, preferably in the matrix material. The metal additives may be present in the form of their oxides, orthophosphates, phosphites, basic phosphates and acid phosphates.

When the catalytic cracking assistant provided by the invention contains a phosphorus additive, the phosphorus additive can be introduced by one of the following methods or a combination of several methods, but is not limited to the methods for introducing the phosphorus additive into the assistant:

1. adding a phosphorus compound to the slurry before the spray drying and forming of the auxiliary agent;

2. after the spray drying and forming of the auxiliary agent, the phosphorus compound is impregnated or chemically adsorbed, and the phosphorus compound is introduced through solid-liquid separation (if needed), drying and roasting processes, wherein the drying temperature can be between room temperature and 400 ℃, preferably 100-300 ℃, the roasting temperature can be between 400-700 ℃, preferably 450-650 ℃, and the roasting time can be between 0.5 and 100 hours, preferably between 0.5 and 10 hours. The phosphorus compound may be selected from one or more of various inorganic and organic compounds of phosphorus. The phosphorus compound may be either readily water-soluble or poorly water-soluble or water-insoluble. Examples of the phosphorus compound include oxides of phosphorus, phosphoric acid, orthophosphates, phosphites, hypophosphites, phosphorus-containing organic compounds, and the like. Preferred phosphorus compounds are selected from one or more of phosphoric acid, ammonium phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate and aluminum phosphate.

Thus, the phosphorus additive may be present in any location where an adjunct may be present, such as may be present inside the pores of the zeolite, on the surface of the zeolite, in the matrix material, or both. The phosphorus additive is present in the form of a phosphorus compound (e.g., an oxide of phosphorus, an orthophosphate, a phosphite, a basic phosphate, an acid phosphate).

The catalytic cracking assistant provided by the invention is suitable for catalytic cracking of various hydrocarbon oils. When the catalyst is used in the catalytic cracking process, the catalyst can be added into a catalytic cracking reactor independently or can be mixed with a catalytic cracking catalyst for use. In general, the promoter provided by the present invention is not more than 30 wt%, preferably 1 to 25 wt%, and more preferably 3 to 15 wt% of the total amount of the FCC catalyst and the promoter mixture provided by the present invention, and the hydrocarbon oil is selected from one or more of various petroleum fractions, such as crude oil, atmospheric residue, vacuum residue, atmospheric wax oil, vacuum wax oil, straight-run wax oil, propane light/heavy deoiling, coker wax oil, and coal liquefaction product. The hydrocarbon oil may contain heavy metal impurities such as nickel and vanadium, and sulfur and nitrogen impurities, for example, the content of sulfur may be as high as 3.0 wt%, the content of nitrogen may be as high as 2.0 wt%, and the content of metal impurities such as vanadium and nickel may be as high as 3000 ppm.

The catalytic cracking auxiliary agent provided by the invention is used in the catalytic cracking process, and the catalytic cracking condition of the hydrocarbon oil is the conventional catalytic cracking condition. Generally, the hydrocarbon oil catalytic cracking conditions include a reaction temperature of 400-600 ℃, preferably 450-550 ℃, and a weight hourly space velocity of 8-120 hours^-1Preferably 8 to 80 hours^-1The ratio of the solvent to the oil (weight ratio) is 1-20, preferably 3-15. The catalytic cracking auxiliary agent provided by the invention can be used for various existing catalytic cracking reactors, such as a fixed bed reactor, a fluidized bed reactor, a riser reactor, a multi-reaction-zone reactor and the like.

The present invention will be further illustrated by the following examples, but the present invention is not limited thereto, and 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 properties of some of the raw materials used in the examples and comparative examples of the present invention are as follows: the pseudoboehmite is an industrial product produced by Shandong aluminum industry company, and has the solid content of 61 percent by weight; the aluminum sol is an industrial product, Al, produced by the Qilu division of the medium petrochemical catalyst₂O₃The content was 21.5 wt%; the water glass is an industrial product, SiO, produced by the middle petrochemical catalyst Qilu division₂Content 28.9 wt.%, Na₂The O content is 8.9 percent; the kaolin is kaolin specially used for a cracking catalyst produced by Suzhou kaolin company, and has the solid content of 78 weight percent; the rectorite is produced by Taixiang famous-class rectorite development Co., Ltd in Hubei province, and the quartz sand<3.5 wt.% of Al₂O₃39.0 wt.%, Fe₂O₃2.0 wt.%, Na₂0.03 wt% of O, and 77 wt% of solid content; SB aluminum hydroxide powder produced by Condex, Germany, Al₂O₃Content 75 wt.%; the gamma-alumina powder is produced by Condex company of Germany, Al₂O₃Content 95 wt%; the hydrochloric acid is produced in Beijing chemical plant, and has chemical purity and concentration of 36-38 wt%.

The TEM-EDS determination method of the invention is described in the research methods of solid catalysts, petrochemical industry, 29(3), 2000: 227.

the measuring method of the micropore specific surface area, the mesopore pore volume and the total pore volume is as follows:

the measurement was carried out by using AS-3, AS-6 static nitrogen adsorption apparatus manufactured by Quantachrome instruments.

The instrument parameters are as follows: the sample was placed in a sample handling system and evacuated to 1.33X 10 at 300 deg.C^-2Pa, keeping the temperature and the pressure for 4h, and purifying the sample. Testing the purified samples at different specific pressures P/P at a liquid nitrogen temperature of-196 DEG C₀The adsorption quantity and the desorption quantity of the nitrogen under the condition are obtained to obtain N₂Adsorption-desorption isotherm curve. Then, the total specific surface area, the micropore specific surface area and the mesopore specific surface area are calculated by utilizing a two-parameter BET formula, and the specific pressure P/P is taken₀The adsorption capacity below 0.98 is the total pore volume of the sample, the pore size distribution of the mesoporous part is calculated by using BJH formula, and the mesoporous pore volume (2-100 nm) and the mesoporous pore volume of 2-20 nm are calculated by adopting an integration method.

The D value is calculated as follows: selecting a crystal grain and a certain crystal face of the crystal grain in a transmission electron mirror to form a polygon, wherein the polygon has a geometric center, an edge and a 10% distance H (different edge points and different H values) from the geometric center to a certain point of the edge, any one of regions in the inward H distance of the edge of the crystal face which is larger than 100 square nanometers and any one of regions in the outward H distance of the geometric center of the crystal face which is larger than 100 square nanometers are respectively selected, measuring the aluminum content, namely Al (S1) and Al (C1), calculating D1 to Al (S1)/Al (C1), respectively selecting different crystal grains to measure for 5 times, and calculating the average value to be D.

Examples 1-6 molecular sieves provided by the present invention were prepared; comparative examples 1-8 comparative molecular sieves were prepared.

Example 1

100g of beta molecular sieve (SiO, produced by catalyst Qilu division)₂/Al₂O₃25, sodium oxide content 4.5 wt%, the same applies below; dry basis weight) was added with water and slurried to obtain a molecular sieve slurry having a solid content of 10% by weight, and 11.4g of a high-alkali sodium metaaluminate solution (Na) was added₂O is 290g/L, Al₂O₃40g/L, the solution density is 1.353g/mL), the temperature is increased to 50 ℃, the constant temperature is kept, the stirring is carried out for 0.5h, and the solution is filtered and washed to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 5.3g of oxalic acid while stirring, then slowly dropwise adding 51g of hydrochloric acid (the mass fraction is 10%) and 17g of fluosilicic acid (the concentration is 20%), heating to 50 ℃, stirring for 1h at constant temperature, filtering, washing and drying to obtain a molecular sieve sample A, wherein the physicochemical properties of the molecular sieve sample A are listed in Table 1.

Comparative example 1

Adding water into 100g of beta molecular sieve (dry mass basis) and pulping to obtain molecular sieve pulp with the solid content of 10 weight percent, and adding 22.4g of high-alkali sodium metaaluminate solution (Na)₂O is 290g/L, Al₂O₃40g/L, the solution density is 1.353g/mL), the temperature is increased to 50 ℃, the constant temperature is kept, the stirring is carried out for 0.5h, and the solution is filtered and washed to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, slowly dropwise adding 240g of fluosilicic acid (the concentration is 20%), heating to 50 ℃, stirring for 1 hour at constant temperature, filtering, washing and drying to obtain a molecular sieve sample DB1, wherein the physicochemical properties of the molecular sieve sample DB1 are shown in Table 1.

Comparative example 2

100g of beta molecular sieve (dry basis mass) was added with water to prepare a molecular sieve slurry having a solid content of 10% by weight, and 25g of a high-alkali sodium metaaluminate solution (Na) was added₂O is 280g/L, Al₂O₃40g/L, the solution density is 1.25g/mL), the temperature is raised to 50 ℃, the constant temperature is kept, the stirring is carried out for 0.5h, the filtration and the washing are carried out until the solution is neutral, the molecular sieve sample DB2 is obtained after the drying, and the physicochemical properties of the molecular sieve sample DB2 are shown in Table 1.

Comparative example 3

100g of beta molecular sieve (dry basis weight) is added with water to prepare molecular sieve slurry with the solid content of 10 weight percent, 5.3g of oxalic acid is added during stirring, 51g of hydrochloric acid (the mass fraction is 10 percent) and 17g of fluosilicic acid (the concentration is 20 percent) are slowly added dropwise, the temperature is increased to 50 ℃, the constant temperature stirring is carried out for 1h, the molecular sieve sample DB3 is obtained after filtration, washing and drying, and the physicochemical properties of the molecular sieve sample DB3 are listed in Table 1.

Comparative example 4

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 16.42g of NaOH (with the purity of 96 percent), heating to 50 ℃, stirring at constant temperature for 0.5h, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 12g of oxalic acid while stirring, then adding 280g of hydrochloric acid (the mass fraction is 10%), heating to 50 ℃, stirring for 1 hour at constant temperature, filtering, washing and drying to obtain a molecular sieve sample DB4, wherein the physicochemical properties of the molecular sieve sample DB4 are shown in Table 1.

Comparative example 5

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 10.42g of NaOH (with the purity of 96 percent), heating to 50 ℃, stirring for 0.5h at constant temperature, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 40g of oxalic acid while stirring, heating to 50 ℃, stirring for 1h at constant temperature, filtering, washing and drying to obtain a molecular sieve sample DB5, wherein the physicochemical properties of the molecular sieve sample DB5 are shown in Table 1.

Comparative example 6

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 10.42g of NaOH (with the purity of 96 percent), heating to 50 ℃, and stirring at constant temperature for 0.5 h; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 300g of hydrochloric acid (mass fraction of 10%) while stirring, heating to 50 ℃, stirring for 1h at constant temperature, filtering, washing and drying to obtain a molecular sieve sample DB6, wherein the physicochemical properties of the molecular sieve sample DB6 are shown in Table 1.

Comparative example 7

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 10.42g of LiOH (the purity is 96 percent), heating to 50 ℃, and stirring at constant temperature for 0.5 h; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 30g of oxalic acid while stirring, slowly dropwise adding 100g of fluosilicic acid (the concentration is 20%), heating to 50 ℃, stirring for 1 hour at constant temperature, filtering, washing and drying to obtain a molecular sieve sample DB7, wherein the physicochemical properties of the molecular sieve sample DB7 are shown in Table 1.

Comparative example 8

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 10.42g of NaOH (with the purity of 96 percent), heating to 50 ℃, and stirring at constant temperature for 0.5 h; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 180g of hydrochloric acid (mass fraction of 10%) while stirring, slowly dropwise adding 100g of fluosilicic acid (concentration of 20%), heating to 50 ℃, stirring for 1h at constant temperature, filtering, washing and drying to obtain a molecular sieve sample DB8, wherein the physicochemical properties of the molecular sieve sample DB8 are listed in Table 1.

Example 2

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 16g of NaOH (with the purity of 96 percent), heating to 50 ℃, stirring at constant temperature for 0.5h, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 16g of oxalic acid while stirring, then slowly dropwise adding 108g of hydrochloric acid (the mass fraction is 10%) and 26g of fluosilicic acid (the concentration is 20%), heating to 50 ℃, stirring at constant temperature for 1h, filtering, washing and drying to obtain a molecular sieve sample B, wherein the physicochemical properties of the molecular sieve sample B are listed in Table 2.

Example 3

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 19g of NaOH (with the purity of 96 percent), heating to 50 ℃, stirring at constant temperature for 0.5h, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 26g of oxalic acid while stirring, slowly dropwise adding 250g of sulfuric acid (with the mass fraction of 10%) and 95g of fluosilicic acid (with the concentration of 20%), heating to 50 ℃, stirring at constant temperature for 1h, filtering, washing and drying to obtain a molecular sieve sample C, wherein the physicochemical properties of the molecular sieve sample C are shown in Table 2.

Example 4

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 30g of NaOH (with the purity of 96 percent), heating to 50 ℃, stirring at constant temperature for 0.5h, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 33g of oxalic acid while stirring, then slowly dropwise adding 240g of hydrochloric acid (the mass fraction is 10%) and 95g of fluosilicic acid (the concentration is 20%), heating to 50 ℃, stirring at constant temperature for 1h, filtering, washing and drying to obtain a molecular sieve sample D, wherein the physicochemical properties of the molecular sieve sample D are listed in Table 2.

Example 5

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 22g of NaOH (with the purity of 96 percent), heating to 50 ℃, stirring at constant temperature for 0.5h, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 5g of citric acid while stirring, then slowly dropwise adding 250g of hydrochloric acid (the mass fraction is 10%) and 130g of fluosilicic acid (the concentration is 20%), heating to 50 ℃, stirring at constant temperature for 1h, filtering, washing and drying to obtain a molecular sieve sample E, wherein the physicochemical properties of the molecular sieve sample E are listed in Table 2.

Example 6

Adding water into 100g of beta molecular sieve (dry basis mass) to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 25g of KOH (with the purity of 96 percent), heating to 50 ℃, stirring at constant temperature for 0.5h, filtering and washing to be neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with the solid content of 20 wt%, adding 35g of oxalic acid while stirring, slowly dropwise adding 190g of nitric acid (the mass fraction is 10%) and 90g of fluosilicic acid (the concentration is 20%), heating to 50 ℃, stirring at constant temperature for 1h, filtering, washing and drying to obtain a molecular sieve sample F, wherein the physicochemical properties of the molecular sieve sample F are shown in Table 2.

As can be seen from the data in Table 1, the conventional alkali treatment (DB2) can enrich the aluminum on the surface of the Beta molecular sieve, and the dealumination by using a single organic acid oxalic acid (DB5) or a single inorganic acid hydrochloric acid dealumination (DB6) and the composite acid of the organic acid oxalic acid and the inorganic acid hydrochloric acid (DB4) can not effectively remove the Al in the molecular sieve, so that the molecular sieve is still enriched with the aluminum on the surface, and a good dealumination effect can be obtained only after the fluosilicic acid is used, and the aluminum distribution of the molecular sieve is improved. When using fluorosilicic acid alone for dealumination (DB1), the aluminum distribution of the molecular sieve was improved, but the mesopores were relatively few. The fluosilicic acid complex organic acid oxalic acid dealumination (DB7) can not obtain higher mesopore proportion. Fluosilicic acid complex mineral acid salt dealumination (DB8), although the mesopore volume was increased, neither the ethyl cyclohexane conversion nor the olefin yield were as high as the molecular sieves provided by the present invention. The invention adopts the steps of firstly carrying out desiliconization treatment on the molecular sieve and then carrying out dealuminization treatment under the synergistic action of three acids by using a composite acid system, so that the aluminum distribution and the acid distribution can be improved on the premise of ensuring the integrity of a molecular sieve crystal structure and a mesoporous pore structure.

Examples 7-10 preparation of a Clay-containing aluminophosphate inorganic binder for use in the invention; comparative example 9a clay-free aluminophosphate inorganic binder, i.e., a aluminophosphate gel, was prepared.

Example 7

0.74 kg of pseudoboehmite (containing Al)₂O₃0.45 Kg), 0.39 Kg kaolin (0.30 Kg dry basis) and 1.6 Kg decationized water, beating for 30 minutes, adding 2.03 Kg concentrated phosphoric acid (chemical purity, 85 wt% phosphoric acid) into the slurry under stirring at a rate of 0.04Kg phosphoric acid/min.kg alumina source, heating to 70 deg.C, and reacting at the temperature for 45 minutes to obtain the final product containing the first clayInorganic Binder, code Binder 1. The material ratios are shown in Table 3.

Examples 8 to 10

Examples 8-10A first clay-containing aluminophosphate inorganic Binder useful in the present invention was prepared according to the same procedure as in example 7, code Binder 2-4. The material ratios are shown in Table 3.

Comparative example 9

Preparing phosphor aluminum glue: 0.66 kg of pseudo-boehmite (0.40 kg on a dry basis) and 1.74 kg of decationized water were slurried for 30 minutes, 2.6 kg of concentrated phosphoric acid (chemical purity, 85 wt% phosphoric acid) was added to the slurry with stirring, the temperature was raised to 70 ℃ and then the reaction was carried out at this temperature for 45 minutes to obtain a phosphoalumina gel (phosphoalumina inorganic Binder), number Binder 5. The material ratios are shown in Table 3.

Examples 11-17 preparation of cracking aids provided by the present invention; comparative examples 10-19 comparative adjuvants were prepared.

Example 11

Taking molecular sieve A, kaolin and pseudo-boehmite, adding decationized water and aluminum sol, pulping for 120 minutes, adding FeCl under stirring₃·6H₂Aqueous solution of O (FeCl)₃Concentration 30 wt.%) to obtain a slurry with a solid content of 30 wt.%, adding hydrochloric acid to adjust the pH of the slurry to 3.0, continuing beating for 45 minutes, then adding the clay-containing phosphorus-aluminum inorganic binder 2 prepared in example 8, stirring for 30 minutes, and spray-drying the obtained slurry to obtain microspheres. And (3) roasting the microspheres at 500 ℃ for 1 hour to obtain the auxiliary C1. The adjuvant formulation is shown in Table 4.

Comparative example 10

Comparative example 10 was prepared by following the same procedure as in example 11 except that the binder 2 was replaced with the aluminophosphate gel binder 5 prepared in comparative example 9 to prepare comparative additive D1. The comparative adjuvant formulation is shown in table 4.

Comparative examples 11 to 18

Comparative examples 11-18 were prepared according to the same procedure as in example 11 except that molecular sieves DB1-DB8 were used instead of A1 to give comparative aids D2-D9. The comparative adjuvant formulation is shown in table 4.

Comparative example 19

Comparative example 19 was prepared in the same manner as in example 11 except that a conventional β molecular sieve (available from catalyst Zihle Ltd., SiO)₂/Al₂O₃Ammonium exchanged to below 0.1 wt% sodium oxide, dry basis mass) substituted a to yield comparative aid D10. The comparative adjuvant formulation is shown in table 4.

Example 12

Taking molecular sieve B, kaolin and pseudo-boehmite, adding decationized water and aluminum sol, pulping for 120 minutes to obtain slurry with the solid content of 30 weight percent, adding hydrochloric acid to adjust the pH value of the slurry to be 3.0, continuing pulping for 45 minutes, then adding the clay-containing phosphorus-aluminum inorganic binder 2 prepared in example 8, stirring for 30 minutes, and spray-drying the obtained slurry to obtain the microspheres. And (3) roasting the microspheres at 500 ℃ for 1 hour to obtain the auxiliary C2. The adjuvant formulation is shown in Table 5.

Example 13

Adding decationized water and alumina sol into molecular sieve C, pulping for 120 min, adding FeCl under stirring₃·6H₂Aqueous solution of O (FeCl)₃Concentration 30 wt.%) to give a slurry having a solid content of 30 wt.%, and then the clay-containing aluminophosphate inorganic binder 1 prepared in example 7 was added thereto, stirred for 30 minutes, and the obtained slurry was spray-dried to obtain microspheres. And (3) roasting the microspheres at 400 ℃ for 1 hour to obtain the auxiliary C3. The adjuvant formulation is shown in Table 5.

Example 14

Adding decationized water and water glass into molecular sieve A and diatomite, pulping for 120 min, adding FeCl while stirring₃·6H₂Aqueous solution of O (FeCl)₃Concentration 30 wt%) to obtain a slurry with a solid content of 30 wt%, adding hydrochloric acid to adjust the pH value of the slurry to 2.0, continuing to pulp for 45 minutes, then adding the clay-containing phosphorus-aluminum inorganic Binder Binder 3 prepared in example 9, stirring for 30 minutes, spray-drying the obtained slurry to obtain microspheres, and roasting the microspheres at 500 ℃ for 1 hour to obtain the auxiliary C4. The adjuvant formulation is shown in Table 5.

Example 15

Adding decationized water into molecular sieve D, pseudoboehmite and kaolin, pulping for 120 min, adding Co (NO) under stirring₃)₂·6H₂Aqueous solution of O (Co (NO)₃)₂Concentration 20 wt%) to obtain a slurry having a solid content of 30 wt%, adding hydrochloric acid to adjust the pH of the slurry to 3.0, continuing to pulp for 45 minutes, then adding the clay-containing phosphorus-aluminum inorganic Binder 4 prepared in example 10, stirring for 30 minutes, and spray-drying the obtained slurry to obtain microspheres.

And roasting the obtained microspheres at 500 ℃ for 1 hour, adding diammonium hydrogen phosphate aqueous solution, heating to 60 ℃ under stirring, reacting at the temperature for 20 minutes, carrying out vacuum filtration and drying on the slurry, and roasting at 500 ℃ for 1 hour to obtain the auxiliary C5. The adjuvant formulation is shown in Table 5.

Example 16

Adding decationized water and water glass into molecular sieve E, kaolin and diatomite, pulping for 120 min, adding Ni (NO) under stirring₃)₂·6H₂Aqueous solution of O (Ni (NO)₃)₂Concentration of 20 wt.%), obtaining a slurry with a solid content of 30 wt.%, adding hydrochloric acid to adjust the pH value of the slurry to 2.0, and continuously beatingPulping for 30 minutes, adding the clay-containing phosphorus-aluminum inorganic binder 2 prepared in example 8 and the phosphorus-aluminum adhesive binder 5 prepared in comparative example 9, pulping for 30 minutes, spray-drying the obtained pulp to obtain microspheres, and roasting the microspheres at 500 ℃ for 1 hour to obtain the auxiliary C6. The adjuvant formulation is shown in Table 5.

Example 17

Adding decationized water and alumina sol into molecular sieve F, pseudo-boehmite and kaolin, pulping for 120 minutes to obtain slurry with the solid content of 30 weight percent, adding hydrochloric acid to adjust the pH value of the slurry to 3.0, continuing pulping for 45 minutes, then adding the clay-containing phosphorus-aluminum inorganic Binder Binder 3 prepared in example 9, then adding diammonium hydrogen phosphate solid, stirring for 30 minutes, and then spray-drying the obtained slurry to obtain the microspheres.

Roasting the obtained microspheres at 500 ℃ for 1 hour, and mixing with FeCl₃·6H₂Aqueous solution of O (FeCl)₃Concentration 4 wt%) according to a weight ratio of 1:1, drying at 120 ℃, and then roasting at 500 ℃ for 1 hour to obtain the assistant C7. The adjuvant formulation is shown in Table 5.

Examples 18 to 24

The following examples illustrate the cracking reaction effect of the cracking aid provided by the present invention in terms of a fixed fluidized bed reactor.

30g of auxiliaries C1-C7 were respectively aged at 800 ℃ for 12 hours in an atmosphere of 100% water vapor. The aging-treated assistants C1-C7 of different weights were mixed with industrial FCC equilibrium catalysts (the industrial FCC equilibrium catalyst with the trade name DVR-3, the main properties are shown in Table 6) of different weights respectively. The catalyst mixture was charged into a reactor of a small-sized fixed fluidized bed reactor, and the raw oil shown in Table 7 was subjected to catalytic cracking. The composition by weight of the catalyst mixture used, the reaction conditions and the reaction results are given in tables 8 and 9.

Comparative examples 20 to 30

The following comparative examples illustrate the use of the comparative additive in a fixed fluidized bed reactor.

The same feed oil was catalytically cracked by the method of example 18, except that the catalysts used were 100% commercial FCC equilibrium catalyst, comparative promoters D1-D10 aged by the method of example 18, and a mixture of commercial FCC equilibrium catalyst, respectively. The composition of the catalyst mixture used, the reaction conditions and the reaction results are given in Table 8.

It can be seen from tables 8 and 9 that, compared with the comparative assistant, the catalytic assistant provided by the present invention can effectively increase the yield of catalytic cracking liquefied gas, especially the yield of isobutene and propylene, significantly increase the concentration of propylene and isobutene in the catalytic cracking liquefied gas, increase the ethylene concentration in the dry gas, and simultaneously increase the octane number of gasoline, increase the yield of catalytic cracking liquid and the conversion rate, and improve the coke selectivity.

TABLE 1

TABLE 2

TABLE 3

TABLE 4

TABLE 5

TABLE 6

Item	Industrial equilibrium catalyst DVR-3
		Metal content, ppm
Ni/V	8762/1387
		Fe/Sb	5214/2512
Ca	1516
		Micro activity index	60

TABLE 7

Raw oil name	Residual oil mixed with wax oil for pipeline transportation
		Density (20 deg.C), g/cm³	0.9070
Viscosity (100 ℃ C.), mm²Second/second	10.41
		Freezing point, DEG C	40
Carbon residue, by weight%	3.1
		The element composition by weight percent
C/H	86.39/12.53
		S/N	0.8/0.29
Four components, by weight%
		Saturated hydrocarbons	56.8
Aromatic hydrocarbons	24.2
		Glue	18.2
Asphaltenes	0.8
		Metal content, ppm
V/Ni	0.8/7.0
		Fe/Cu	7.8/0.1
Na	2.6
		Distillation range, deg.C
Initial boiling point/5%	241/309
		10％/20％	343/387
30％/40％	413/432
		50％/60％	450/466
70％/80％	493/535

TABLE 8

TABLE 9

Claims

1. The catalytic cracking assistant containing the Beta molecular sieve rich in the mesopores is characterized by comprising the Beta molecular sieve rich in the mesopores in an amount of 10-75 wt% on a dry basis by taking the weight of the assistant on a dry basis as a reference, and taking Al as the reference₂O₃、P₂O₅And 3-30 wt% of a first clay-containing aluminophosphate inorganic binder, based on the sum of the dry weights of the first clays, 3-30 wt% of other inorganic binders, based on oxides, 0-60 wt% of a second clay, based on dry weights, and 0-15 wt% of a group VIII metal additive, based on oxides; wherein,

the first clay-containing phosphorus aluminum inorganic binder comprises Al based on the dry weight of the first clay-containing phosphorus aluminum inorganic binder₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and 1-40 wt% of first clay calculated by dry weight, wherein the weight ratio of P/Al is 1.0-6.0, the pH value is 1-3.5, and the solid content is 15-60 wt%;

the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.4 and less than or equal to 0.8, wherein D is Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the inward H distance of the crystal face edge of the molecular sieve crystal grain measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the outward H distance of the geometric center of the crystal face of the molecular sieve crystal grain measured by the TEM-EDS method, wherein H is 10 percent of the distance from a certain point of the crystal face edge to the geometric center of the crystal face; the specific surface area of the micropores of the molecular sieve is 350-500 m²The proportion of the mesoporous volume of the molecular sieve in the total pore volume is 30-70% by volume.

2. The adjuvant according to claim 1, wherein the molecular sieve has an Al distribution parameter D satisfying: d is more than or equal to 0.55 and less than or equal to 0.75; the specific surface area of the micropores of the molecular sieve is 370-450 m²And/g, the proportion of the mesoporous volume of the molecular sieve in the total pore volume is 35-60% by volume.

3. The adjuvant according to claim 1, wherein the first clay is at least one selected from kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomaceous earth; the second clay is at least one selected from kaolin, metakaolin, diatomite, sepiolite, attapulgite, montmorillonite and rectorite; the inorganic oxide binder includes at least one selected from the group consisting of pseudoboehmite, alumina sol, silica-alumina sol, and water glass.

4. A method according to any one of claims 1 to 3The auxiliary agent of (1), wherein the auxiliary agent further contains P based on the dry weight of the auxiliary agent₂O₅Up to 25 wt% of a phosphorus additive.

5. The adjuvant according to claim 4, wherein the adjuvant comprises 20-60 wt% of mesoporous enriched Beta molecular sieve on a dry basis, calculated as Al, based on the weight of the adjuvant on a dry basis₂O₃、P₂O₅And 8-25 wt% of a phosphorus-aluminum inorganic binder containing the first clay calculated by the sum of the dry weight of the first clay, 5-25 wt% of other inorganic binders calculated by oxides, 10-45 wt% of a second clay calculated by the dry weight, and P₂O₅0-10% by weight of a phosphorus additive and 1-10% by weight of a group VIII metal additive, calculated as the oxide.

6. The adjuvant of claim 4, wherein the phosphorus additive is introduced to the adjuvant in the form of a phosphorus-containing compound comprising at least one selected from the group consisting of oxides, phosphates, phosphites, basic phosphates, and acid phosphates of phosphorus;

the group VIII metal comprises at least one selected from Fe, Co and Ni, and the group VIII metal additive is introduced to the promoter in the form of a metal-containing compound comprising at least one selected from the group consisting of oxides, hydroxides, chlorides, nitrates, sulfates, phosphates and organic compounds.

7. The adjuvant according to claim 1, wherein the preparation of the first clay-containing aluminophosphate inorganic binder comprises:

(1) pulping and dispersing an alumina source, first clay and water into slurry with the solid content of 8-45 wt%; the alumina source is aluminum hydroxide and/or aluminum oxide which can be peptized by acid, first clay and Al which are calculated by dry weight₂O₃The weight ratio of the alumina source is (1-40) to (15-40);

(2) adding concentrated phosphoric acid into the slurry obtained in the step (1) according to the weight ratio of P/Al to 1-6 under stirring;

(3) and (3) reacting the slurry obtained in the step (2) at the temperature of 50-99 ℃ for 15-90 minutes.

8. A preparation method of a catalytic cracking assistant comprises the following steps:

mixing the Beta molecular sieve rich in mesopores, the phosphorus-aluminum inorganic binder containing the first clay and water, adding or not adding the second clay, pulping, and spray-drying; wherein, a phosphorus additive is introduced or not introduced, and a group VIII metal additive is introduced or not introduced;

based on the weight and the dry basis weight of the preparation raw materials of the auxiliary agent, the preparation raw materials of the auxiliary agent contain 10-75 wt% of Beta molecular sieve rich in mesopores on the dry basis, and the Beta molecular sieve is calculated by Al₂O₃、P₂O₅And 3-30 wt% of a phosphorus-aluminum inorganic binder containing the first clay calculated by the sum of the dry weight of the first clay, 3-30 wt% of other inorganic binders calculated by oxides, 0-60 wt% of a second clay calculated by the dry weight, and P₂O₅Up to 25 wt.% of a phosphorus additive and 0-15 wt.% of a group VIII metal additive, calculated as the oxide;

the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.4 and less than or equal to 0.8, wherein D is Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the distance H from the edge of the crystal face of the molecular sieve crystal grain to the inside measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the distance H from the geometric center of the crystal face of the molecular sieve crystal grain to the outside measured by the TEM-EDS method, wherein H is the aluminum content from a certain point on the edge of the crystal face to a certain point on the edge of the crystal face10% of the geometrical center distance of the crystal face; the specific surface area of the micropores of the molecular sieve is 350-500 m²The proportion of the mesoporous volume of the molecular sieve in the total pore volume is 30-70% by volume.

9. The preparation method of claim 8, wherein the preparation step of the mesoporous enriched Beta molecular sieve comprises:

a. carrying out alkali treatment on the sodium type Beta molecular sieve in an alkaline solution, and filtering and washing to obtain an alkali-treated molecular sieve;

b. and (b) dealuminizing the alkali-treated molecular sieve obtained in the step a in a composite acid dealuminating agent solution consisting of fluosilicic acid, organic acid and inorganic acid, and filtering and washing to obtain the Beta molecular sieve rich in mesopores.

10. The production method according to claim 9, 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, aqueous ammonia and an overbased sodium metaaluminate solution; the sodium content of the high-alkali sodium metaaluminate solution is 270-310 g/L, the aluminum content is 30-50 g/L and the density of the high-alkali sodium metaaluminate solution is 1.25-1.45 g/mL.

11. The preparation method according to claim 10, wherein the conditions of the alkali treatment in step a include: the weight ratio of the molecular sieve to the alkali in the alkaline solution on a dry basis is 1: (0.02-0.3); wherein the weight of the alkali in the sodium hydroxide solution is based on the weight of sodium hydroxide, the weight of the alkali in the potassium hydroxide solution is based on the weight of potassium hydroxide, the weight of the alkali in the lithium hydroxide solution is based on the weight of lithium hydroxide, the weight of the alkali in the ammonia water is based on the weight of ammonia monohydrate, and the weight of the alkali in the high-alkali sodium metaaluminate solution is based on the weight of sodium oxide.

12. The preparation method according to claim 9, wherein the conditions of the alkali treatment in step a include: the temperature of alkali treatment is 25-100 ℃, and the time of alkali treatment is 0.5-6 hours.

13. The production method according to claim 9, wherein the organic acid in step b is at least one selected from the group consisting of ethylenediaminetetraacetic acid, oxalic acid, citric acid and sulfosalicylic acid, and the inorganic acid is at least one selected from the group consisting of hydrochloric acid, sulfuric acid and nitric acid.

14. The production method according to claim 9, wherein the conditions of the dealumination treatment in step b include: the weight ratio of the molecular sieve, the fluosilicic acid, the organic acid and the inorganic acid is 1: (0.03-0.5): (0.05-0.4): 0.05-0.5); the treatment temperature is 25-100 ℃, and the treatment time is 0.5-6 hours.

15. The production method according to claim 9, wherein the conditions of the dealumination treatment in step b include: the weight ratio of the molecular sieve, the fluosilicic acid, the organic acid and the inorganic acid is 1: (0.05-0.3):(0.1-0.3):(0.1-0.3).

16. The preparation method according to claim 8, wherein the first clay is at least one selected from kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomaceous earth; the second clay is at least one selected from kaolin, metakaolin, diatomite, sepiolite, attapulgite, montmorillonite and rectorite; the inorganic oxide binder includes at least one selected from the group consisting of pseudoboehmite, alumina sol, silica-alumina sol, and water glass.

17. The production method according to claim 8, wherein the phosphorus additive is introduced into the auxiliary in the form of a phosphorus-containing compound including at least one selected from an oxide of phosphorus, a phosphate, a phosphite, a basic phosphate, and an acid phosphate;

18. The method of claim 8, wherein the first clay-containing aluminophosphate inorganic binder is prepared by a method comprising: