CN114425429A

CN114425429A - Wear-resistant high-yield low-carbon olefin catalyst and preparation method thereof

Info

Publication number: CN114425429A
Application number: CN202011103672.7A
Authority: CN
Inventors: 孙敏; 杨雪; 宋海涛; 沈宁元; 黄志青
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: 2020-10-15
Filing date: 2020-10-15
Publication date: 2022-05-03

Abstract

The invention belongs to the field of catalyst preparation, and relates to an abrasion-resistant high-yield low-carbon olefin catalyst and a preparation method thereof, wherein the catalyst comprises the following components in parts by weight: 10-60% by weight on a dry basis of cracking active components, 20-60% by weight on a dry basis of binders, 0-70% by weight on a dry basis of second clays; wherein the binder comprises 1-50 wt% of zirconium sol, 50-99 wt% of phosphorus-aluminum inorganic binder and 0-45 wt% of third binder on a dry basis based on the dry basis weight of the binder. The preparation method of the catalytic cracking catalyst comprises the following steps: the cracking reactive component, binder, water and optionally clay are slurried and spray dried. The catalyst has better abrasion resistance, and can be used for producing low-carbon olefin by catalytic cracking of hydrocarbon oil.

Description

Wear-resistant high-yield low-carbon olefin catalyst and preparation method thereof

Technical Field

The present invention relates to a catalytic cracking catalyst, and more particularly to a catalytic cracking catalyst having excellent wear resistance and a method for preparing the same.

Background

In recent years, the demand for propylene has increased rapidly, and the global propylene consumption will increase by about 5% on average, more than 3.5% for ethylene. However, the ratio of propylene to ethylene in steam cracking cannot be flexibly adjusted, the reaction temperature is as high as 800 ℃, and the energy consumption accounts for about 40 percent of the energy consumption of petrochemical industry. Thus, the large production of propylene by FCC is an effective and efficient way to meet the growing demand.

Microporous zeolite catalytic materials are widely used in the petroleum refining and chemical processing industries due to their excellent shape selective catalytic properties and high cracking activity. At present, most of catalytic cracking catalysts adopt alumina sol and peptized pseudo-boehmite as binders, and the matrix has low activity, poor selectivity and poor strength. In recent years, aluminophosphates have begun to be introduced as binders for the preparation of catalytic cracking catalysts.

CN1076714A discloses a phosphorus-containing hydrocarbon cracking catalyst prepared by using phosphorus-containing aluminum sol as a binder. The phosphorus-containing aluminium sols used were prepared according to the methods disclosed in CN170384A and CN 170385A. However, the performance of the phosphorus-containing alumina sol catalyst still needs to be improved.

CN102847547A discloses an inorganic binder containing a phosphorus-aluminum compound and a preparation method thereof, wherein the binder contains 15-40 wt% of Al₂O₃45-80% by weight of P₂O₅And 1-40 wt% of clay, wherein the weight ratio of P/Al is 1-6, the pH value is 1-3.5, and the solid content is 15-60 wt%. The preparation method comprises the following steps: aluminium hydroxide and/or aluminium oxide which can be peptized by acid and clay are beaten with de-cationic water to be dispersed into slurry with the solid content of 15-45 wt%, concentrated phosphoric acid is added into the slurry according to the weight ratio of P/Al to 1-6 under stirring, and then the reaction is carried out for 15-90 minutes at 50-99 ℃. The preparation method provided by the publication can avoid the solidification of the adhesive caused by the heat release and overtemperature of the nonuniform local instant violent reaction of the materials, and the obtained adhesiveThe agglomeration agent can improve the attrition resistance, activity and selectivity of the FCC catalyst. However, the binder has poor performance in some cases.

CN102211039B provides a catalytic cracking catalyst and a preparation method thereof, which comprises the steps of mixing and pulping a molecular sieve, zirconia powder and an aluminum binder, adding the zirconia powder into slurry for pulping, adjusting the pH value of the slurry to 2-5 by using inorganic acid, and then carrying out spray drying, wherein the zirconia powder is prepared by mixing an aqueous solution of a zirconium salt and ammonia water. The catalyst prepared by the method has strong calcium pollution resistance, is used for cracking hydrocarbon oil containing calcium, and has high propylene yield. However, the method introduces zirconium in the form of oxide, which is difficult to peptize again, and can affect the strength improvement of the catalyst. This method has limited effectiveness in the case of using an alumino-phosphate binder.

Disclosure of Invention

The invention aims to solve the technical problem that the catalytic cracking catalyst using a phosphor-alumina gel binder as a matrix in the prior art is poor in performance, and provides a catalytic cracking catalyst which is good in strength, high in conversion rate and high in low-carbon olefin selectivity.

The invention provides a catalytic cracking catalyst for producing light olefins in high yield, which comprises the following components: 10-60% by weight on a dry basis of cracking active components, 20-60% by weight on a dry basis of binders, 0-70% by weight on a dry basis of second clays; wherein the binder comprises 1-50 wt% of zirconium sol, 50-99 wt% of phosphorus-aluminum inorganic binder and 0-45 wt% of third binder on a dry basis, based on the dry basis weight of the binder;

the cracking active component comprises a first molecular sieve and an optional second molecular sieve, wherein the first molecular sieve is a five-membered ring structure molecular sieve; the first molecular sieve in the cracking active component accounts for more than 70 percent on a dry basis; preferably, the cracking active component comprises 70-100 wt% of the first molecular sieve and 0-30 wt% of the second molecular sieve;

the zirconium sol: including 0.5 to 20 mass% of ZrO₂A stabilizer, an alkali cation and water,wherein the mol ratio of the stabilizer to Zr is 1-6, and the pH value of the zirconium sol is 1-7;

the phosphor-aluminum inorganic binder contains Al₂O₃15-40 wt.% calculated as P of an alumina source component₂O₅45-80% by weight of a phosphorus component and 0-40% by weight, on a dry basis, of a first clay, the P/Al weight ratio being 1-6, the pH value being 1-3.5 and the solids content being 15-60% by weight.

The catalytic cracking catalyst according to the above technical solution, wherein the third binder is selected from one or more of silica sol, alumina sol, silica-alumina gel, acidified aluminum oxide, and metal-modified aluminum oxide.

The catalytic cracking catalyst according to any of the above technical solutions, wherein the preparation method of the phosphorus-aluminum inorganic binder comprises:

(1) pulping an alumina source, first clay and water to disperse into slurry with 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 in dry basis₂O₃The weight ratio of the alumina source is 0-40: 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 the concentration of the concentrated phosphoric acid is, for example, 50 to 98% by weight.

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

The catalytic cracking catalyst according to any of the above technical solutions, preferably, the phosphorus-aluminum inorganic binder comprises 15-35 wt% of Al derived from the alumina source based on the dry weight of the phosphorus-aluminum inorganic binder₂O₃50-75% by weight of P₂O₅And 0-35 wt% first clay, e.g., 5-30 wt% first clay, on a dry basis.

The catalytic cracking catalyst according to any of the preceding claims, wherein the P/Al weight ratio is preferably 2-5.

The catalytic cracking catalyst according to any of the above claims, wherein the alumina source may be one or more of rho-alumina, chi-alumina, eta-alumina, gamma-alumina, kappa-alumina, delta-alumina, theta-alumina, gibbsite, surge flash, nordstrandite, diaspore, boehmite and pseudo-boehmite.

The catalytic cracking catalyst according to any one of the preceding technical schemes, wherein the first clay is one or more of kaolin, montmorillonite, diatomaceous earth, halloysite, pseudohalloysite, saponite, rectorite, sepiolite, attapulgite, hydrotalcite and bentonite, and preferably one or more of kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomaceous earth.

The catalytic cracking catalyst according to any one of the preceding claims, wherein the second clay may be one or more of kaolin, montmorillonite, diatomaceous earth, halloysite, pseudohalloysite, saponite, rectorite, sepiolite, attapulgite, hydrotalcite, and bentonite.

According to the catalytic cracking catalyst of any one of the above technical schemes, preferably, the size of the zirconium sol gel particles is between 5nm and 15nm, the average particle size is about 10nm, and the concentration is more than 90%. The about 10nm refers to 10 +/-2 nm. The concentration ratio is the proportion of the number of colloidal particles with the size of about 10nm in the measured colloidal particles in the zirconium sol sample to the total number of the measured colloidal particles, and a zirconium sol sample image can be obtained through a TEM and obtained through computer image analysis. The size of the colloidal particles refers to the diameter of the largest circumscribed circle in a colloidal particle projection drawing, and the average particle size is the arithmetic average of the sizes of the sample colloidal particles.

According to the catalytic cracking catalyst of any one of the above technical schemes, preferably, the zirconium sol is dried at 100 ℃ for 6 hours, and is roasted at 600 ℃ for 2-6 hours for heat treatment, so that a monoclinic phase and a tetragonal phase of the obtained product coexist, and the ratio of the monoclinic phase to the tetragonal phase is preferably 0.05-0.6: 1; and/or drying the zirconium sol at 100 ℃ for 6h, roasting at 800 ℃ for 2-6 h, and carrying out heat treatment on the zirconium sol to obtain a product containing ZrO₂Are present in the tetragonal phase.

In the catalytic cracking catalyst according to any of the above technical solutions, the stabilizer in the zirconium sol is an organic acid, and in one embodiment, the stabilizer is preferably at least one of glycolic acid, oxalic acid, acetic acid, malonic acid, malic acid, tartaric acid, succinic acid, adipic acid, maleic acid, itaconic acid, citric acid, and the like, and more preferably one or more of acetic acid, oxalic acid, or citric acid.

In the catalytic cracking catalyst according to any of the above embodiments, in the zirconium sol, the alkali cation (also referred to as basic cation) is preferably a nitrogen-containing cation, such as ammonium ion or a nitrogen-containing cation formed by hydrolysis of a water-soluble organic base, such as one or more of methylamine, dimethylamine, trimethylamine, triethylamine, ethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, monomethyltriethylammonium hydroxide, monomethyltriethanolamine hydroxide, monomethyltributylammonium hydroxide, and the like.

In the catalytic cracking catalyst according to any of the above technical solutions, the molar ratio of the alkali cation to Zr in the zirconium sol is preferably 1 to 8.

In the catalytic cracking catalyst according to any of the above technical solutions, preferably, the zirconium sol further contains an inorganic acid group and/or an alcohol, and the molar ratio of the inorganic acid group and/or the alcohol to Zr is preferably 1 to 6, for example, 1 to 4: 1. inorganic acid radical such as one or more of sulfate radical, chloride ion and nitrate radical, and alcohol such as one or more of methanol, ethanol, propanol and butanol.

The catalytic cracking catalyst according to any of the preceding claims, wherein the zirconium sol has a pH of preferably 1.5 to 5, more preferably 2 to 4, and even more preferably 2 to 3.

According to any one of the above technical solutions, the preparation method of the zirconium sol comprises the following steps:

(1) preparing a zirconium source solution from ZrO₂The concentration of the zirconium source solution is 0.5 to 20 mass%, for example, 1 to 18 mass% or 5 to 15 mass%; fitting for mixingThe zirconium source preparation solution can be carried out at room temperature; the room temperature can be 15-40 ℃;

(2) adding a stabilizer into the zirconium source solution to obtain a first mixed solution, preferably, stirring for 0.5-3 hours at room temperature to 90 ℃ to fully react to obtain a first mixed solution; wherein the molar ratio of the stabilizer to zirconium is 1-6:

(3) and adding alkali liquor into the first mixed solution at the room temperature of 50 ℃ below zero to obtain zirconium sol, wherein the alkali liquor is used in an amount that the pH value of the zirconium sol is 1-7.

According to the technical scheme, in the zirconium sol preparation method, alkali liquor is slowly added into the first mixed solution to obtain clear and transparent zirconium sol. The slow addition may be, for example, dropwise, or a certain addition rate may be controlled, for example, the addition rate is 0.05ml to 50 ml/min/L of the first mixed solution, for example, 0.1ml to 30ml of alkali solution/min/L of the first mixed solution or 1ml to 35ml of alkali solution/min/L of the first mixed solution or 0.05ml to 10 ml/min/L of the first mixed solution or 0.1ml to 5 ml/min/L of the first mixed solution. In one embodiment, the lye is added slowly to the first mixed solution by means of a pump, for example a peristaltic pump. Preferably, the amount of lye added is such that the pH of the zirconium sol is from 1.5 to 5, such as from 2 to 4, more preferably from 2 to 3.

According to any one of the above aspects, in the method for preparing a zirconium sol, the zirconium source is one or more of an inorganic zirconium salt such as one or more of zirconium tetrachloride, zirconium oxychloride, zirconium acetate, zirconium nitrate, zirconyl sulfate and zirconyl carbonate or an organic zirconium salt; the organic zirconium salt is one or more of zirconium n-propoxide, zirconium isopropoxide, zirconium ethoxide and zirconium butoxide.

In any one of the above embodiments, in the method for preparing a zirconium sol, the stabilizer is an organic acid capable of forming a coordination polymer with zirconium, and the stabilizer is preferably at least one of glycolic acid, acetic acid, oxalic acid, malonic acid, malic acid, tartaric acid, succinic acid, adipic acid, maleic acid, itaconic acid, citric acid, and the like, and more preferably one or more of acetic acid, oxalic acid, and citric acid.

In any one of the above embodiments, in the method for preparing zirconium sol, the alkali solution is selected from aqueous ammonia or an aqueous solution of a water-soluble organic base, such as one or more of methylamine, dimethylamine, trimethylamine, methylamine, dimethylamine, triethanolamine, triethylamine, ethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, monomethyltriethylammonium hydroxide, monomethyltriethanolamine hydroxide, monomethyltributylammonium hydroxide.

The invention also provides a preparation method of the catalytic cracking catalyst, which comprises the following steps: the cracking reactive component, binder, water and optionally clay are slurried and spray dried.

The invention provides a catalytic cracking method, which comprises the step of carrying out contact reaction on heavy oil and the catalytic cracking catalyst in any technical scheme or the catalyst obtained by the preparation method of the catalytic cracking catalyst in any technical scheme.

The catalytic cracking catalyst provided by the invention has at least one of the following beneficial effects, preferably a plurality of or all of the following beneficial effects:

(1) the catalyst provided by the invention is used for catalytic cracking of hydrocarbon oil, and has high hydrocarbon oil conversion activity.

(2) The catalyst provided by the invention is used for catalytic cracking conversion, and the selectivity of low-carbon olefin is high.

(3) The catalyst provided by the invention is used for catalytic cracking conversion of hydrocarbon oil, the propylene yield is higher, and the propylene concentration in liquefied gas is higher.

(4) The catalyst provided by the invention is used for catalytic cracking conversion of hydrocarbon oil, and the concentration of ethylene in dry gas is higher.

(5) The catalyst provided by the invention has good strength and low abrasion index.

(6) In the case of using the modified NSY molecular sieve, the coke selectivity of the catalyst is better.

The preparation method of the catalyst provided by the invention has one or more of the following advantages:

(1) the phosphorus-aluminum adhesive has good stabilizing effect on the five-membered ring molecular sieve.

(2) The invention uses the newly developed zirconia sol, and can further improve the abrasion strength of the catalyst under the condition of containing the phosphor-alumina gel.

(3) The zirconium element and the P element are introduced in the form of sol, the zirconium sol and the phosphorus-aluminum-containing inorganic binder synergistically act to make up the problem of weak adhesion of the P-Al adhesive, and the propylene selectivity of ZSM-5 can be improved, so that the heavy oil conversion rate and the low-carbon olefin selectivity are improved.

(4) According to the preparation method of the catalytic cracking catalyst, the zirconium element and the P element are introduced in a sol form, and the catalyst contains the newly developed modified NSY molecular sieve active component, so that the catalyst has higher activity, and the heavy oil conversion rate and the low-carbon olefin selectivity are improved.

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.

According to the catalytic cracking catalyst of the invention, the first molecular sieve is a molecular sieve with five-membered rings, the molecular sieve with five-membered rings is one or more of MFI structure molecular sieve (or MFI type molecular sieve), BEA structure molecular sieve, mordenite and the like, and preferably one or more of BEA structure molecular sieve and MFI structure molecular sieve. The MFI structure molecular sieve comprises at least one of a rare earth-containing MFI molecular sieve, a phosphorus-containing MFI molecular sieve and a transition metal-containing MFI molecular sieve, wherein the phosphorus-containing MFI molecular sieve can further contain a transition metal, and the transition metal is preferably one or more of Fe, Co, Ni, Cu, Mn, Zn, Sn and Bi, and more preferably one or more of Fe, Co, Ni, Zn and Cu; the BEA structure molecular sieve such as Beta molecular sieve can be a BEA structure molecular sieve obtained by amine-free crystallization, and can also be a BEA structure molecular sieve obtained by roasting a molecular sieve prepared by a template method; the mordenite can include at least one of a high-silicon mordenite or a low-silicon mordenite. Preferably, the first molecular sieve comprises an MFI structure molecular sieve.

The catalytic cracking catalyst according to the invention, optionally containing a second molecular sieve, preferably in an amount of 0-18 wt.%, 1-15 wt.%, or 2-10 wt.%, or 5-10 wt.%.

According to any of the above technical solutions, in the catalytic cracking catalyst provided by the present invention, the second molecular sieve is preferably a large pore molecular sieve, the second molecular sieve is preferably a Y-type molecular sieve, which may or may not contain a rare earth element, and the rare earth content in the Y-type molecular sieve is RE₂O₃Calculated as 0-20 wt%. The unit cell constant of the Y-type molecular sieve can be 2.430nm-2.480 nm.

According to the catalytic cracking catalyst provided by the invention, the Y-type molecular sieve is preferably one or more of a DASY molecular sieve, a DASY molecular sieve containing rare earth, a USY molecular sieve containing rare earth, a REY molecular sieve, a HY molecular sieve, a REHY molecular sieve and a Y-type molecular sieve synthesized by modified kaolin through in-situ crystallization.

According to one embodiment of the catalytic cracking catalyst provided by the invention, the Y-type molecular sieve is an ultra-stable Y-type molecular sieve, and the content of rare earth in the ultra-stable Y-type molecular sieve is RE₂O₃Calculated as 0-12 wt%, e.g. 1-12 wt%. The content of sodium oxide is not more than 2 wt%, and the unit cell constant of X-ray diffraction measurement is 2.435-2.460 nm.

According to an embodiment of the preparation method of the catalytic cracking catalyst, the catalyst provided by the invention contains a second molecular sieve, the second molecular sieve includes a Y-type molecular sieve synthesized by in-situ crystallization of modified kaolin, the content of sodium oxide in the Y-type molecular sieve synthesized by in-situ crystallization of modified kaolin is preferably less than 2 wt%, and preferably, the Y-type molecular sieve synthesized by in-situ crystallization of modified kaolin is a modified NSY-type molecular sieve. NSY molecular sieve synthesized by kaolin in-situ crystallization is modified to obtain modified NSY type molecular sieve, wherein the modification comprises ultra-stableChemical treatment and/or ion exchange treatment. The modified NSY-type molecular sieve has a sodium oxide content of less than 2 wt%. The rare earth content in the modified NSY molecular sieve is RE₂O₃Calculated as 0-20 wt%.

In one embodiment, the modified NSY molecular sieve is an ion-modified ultrastable NSY molecular sieve, and the rare earth content of the molecular sieve is RE₂O₃Calculated as 0-12 wt%, and the unit cell constant is 2.435-2.460 nm.

In one embodiment, the modified NSY-type molecular sieve is an ionically-modified ultrastable NSY molecular sieve, and the amount of ionically-modified ultrastable NSY molecular sieve in the catalytic cracking catalyst is, for example, 1 to 10 wt.% or 5 to 10 wt.% on a dry basis. Such as ammonium exchange and/or rare earth exchange.

According to a preferred embodiment of the catalytic cracking catalyst of the present invention, the Y molecular sieve is a modified NSY molecular sieve, and the modified NSY molecular sieve is obtained by modifying a NSY molecular sieve synthesized by kaolin in situ crystallization (referred to as a NSY molecular sieve synthesized by in situ crystallization). Such as ion exchange and/or ultra-stabilization. The modification treatment reduces the content of sodium oxide in the NSY molecular sieve synthesized by kaolin in-situ crystallization to below 2 weight percent. The NSY molecular sieve synthesized by kaolin in-situ crystallization is measured by an X-ray diffraction method, the crystallinity of the molecular sieve is more than or equal to 60 percent by a peak height method, and the ratio of the crystallinity to the crystallinity of the molecular sieve by the peak area method is K1, and K1 is 0.76-0.89; by unit cell constant a₀The measured silicon-aluminium ratio is 5.0-5.5, and the ratio of the measured silicon-aluminium ratio to the chemically measured silicon-aluminium ratio is K2, and K2 is 0.87-0.93, wherein the silicon-aluminium ratios are mole ratios of silicon oxide to aluminum oxide.

According to the crystal crystallization common knowledge, the difference between the crystallinity measured by the peak height method and the crystallinity measured by the peak area method is related to the size of the crystal grains. The Y-type molecular sieve composite material (the composite material for short) is set with a crystal grain coefficient K1, and K1 is S_{Peak height}/S_{Peak area}I.e. the ratio of the crystallinity of the peak height method to the crystallinity of the peak area method. The size of the K1 value indicates the size of the crystal grains, and the K1 value is large and the grain size is large.

From the unit cell constant a₀The calculated mole ratio of silica to alumina is the framework silica to alumina ratio of the molecular sieve, and the mole ratio of silica to alumina determined by chemical methods is the overall silica to alumina ratio of the composite material. The NSY molecular sieve synthesized by kaolin in-situ crystallization has unit cell constant a₀The framework silicon to aluminum ratio determined is calculated to be 5.0 to 5.5, preferably 5.2 to 5.5, while the overall silicon to aluminum ratio determined by chemical means is the macroscopic silicon to aluminum ratio of the entire material. The two values of the framework silicon-aluminum ratio and the integral silicon-aluminum ratio are related to the framework integrity and the purity of the molecular sieve in the composite material, the NSY molecular sieve synthesized by kaolin in-situ crystallization is obtained by transforming the metakaolin into crystals, wherein a part of the metakaolin is in an intermediate body transformed into the Y-type molecular sieve, and therefore, the intermediate body coefficient K2 is set, namely K2 is the framework silicon-aluminum ratio/the integral silicon-aluminum ratio. The magnitude of the K2 value indicates the compounding degree of the composite material, and the smaller the K2 value is, the more intermediates are contained. Preferred K2 is 0.87-0.92, more preferably 0.88-0.90.

The kaolin clay synthesized by in-situ crystallization of NSY molecular sieve (also called Y-type molecular sieve composite material) preferably has K1 ═ 0.77-0.88, such as K1 ═ 0.81-0.88 or K1 ═ 0.86-0.88 and K2 ═ 0.87-0.91.

The catalytic cracking catalyst of the invention is characterized in that preferably, the NSY molecular sieve synthesized by kaolin in situ crystallization has a sphere-like shape of 5-20 microns, wherein the crystallinity of the peak height method is more than or equal to 60 percent, namely the mass percentage of the NaY molecular sieve is at least 60 percent. Preferably, the degree of crystallinity by peak height method is greater than 75%, more preferably greater than or equal to 80%.

The catalytic cracking catalyst of the present invention, wherein K1 is 0.80-0.89.

The catalytic cracking catalyst of the present invention, wherein K1 is 0.80-0.85.

The catalytic cracking catalyst of the present invention, wherein K2 is 0.87-0.92.

The catalytic cracking catalyst of the present invention, wherein K2 is 0.88-0.90.

The catalytic cracking catalyst according to any one of the preceding claims, wherein K1-0.77-0.88 and K2-0.87-0.91.

In the present invention, the mesopores having a pore diameter of more than 0.8nm are defined as mesopores and macropores. The NSY molecular sieve synthesized by kaolin in-situ crystallization has proper medium and large porosity, wherein the large porosity is 10-20%.

The catalytic cracking catalyst provided by the invention is characterized in that the preparation method of the NSY molecular sieve synthesized by kaolin in-situ crystallization comprises the following steps:

(1) roasting and dehydrating kaolin at 500-900 deg.C to convert into metakaolin, and pulverizing to obtain metakaolin powder with particle size less than 10 μm;

(2) adding a directing agent, sodium silicate, a sodium hydroxide solution and water into the metakaolin powder to prepare a reaction raw material A, wherein the mass ratio of the directing agent to the metakaolin is 0.01-1.0, and the proportion of the reaction raw material A is (1-2.5) Na₂O：Al₂O₃：(4-9)SiO₂：(40-100)H₂O molar ratio;

(3) crystallizing the reaction raw material A for 1-70h under stirring at 88-98 ℃, and then supplementing a second silicon source to obtain a reaction raw material B, wherein the second silicon source accounts for 0.1-10 wt% of the total silicon charge, calculated by silicon oxide;

(4) crystallizing the reaction material B at 88-98 deg.c while stirring and recovering the product.

According to the preparation method of the catalytic cracking catalyst provided by the invention, the modified NSY molecular sieve can be obtained by treating the NSY molecular sieve which is synthesized by kaolin in-situ crystallization by any method capable of reducing the sodium content in the molecular sieve so that the sodium oxide content in the molecular sieve does not exceed 2 weight percent, for example, by ion exchange. The ion exchange can be carried out by adopting ammonium salt and/or rare earth salt solution, and the invention has no special requirement. In one embodiment, the ion exchange is performed such that the rare earth content of the resulting modified NSY molecular sieve is as RE₂O₃In an amount of 10 wt% to 20 wt%, for example 10 wt% to 20 wt% or 1 to 15 wt% or 4 to 12 wt%, the sodium oxide content being less than 2 wt%. One embodiment, the kaolin is synthesized by in-situ crystallizationThe NSY molecular sieve is mixed with the exchange solution, and stirred for 10-120 minutes at 20-90 ℃, the above process can be carried out once or more times, and the exchange solution of each exchange can contain ammonium ions, rare earth ions or both ammonium ions and rare earth ions. Preferably, the exchange solution has an ammonium salt concentration of 5-700g/L, e.g. 5-100g/L and/or a rare earth salt concentration as RE₂O₃In the range of 2 to 450g/L, for example 5 to 200g/L or 5 to 400 g/L. Such as one or more of ammonium chloride, ammonium nitrate, ammonium sulfate. The rare earth salt is one or more of rare earth chloride and rare earth nitrate. The rare earth can comprise one or more of lanthanide rare earth and actinide rare earth, for example, one or more of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, TB, Dy, Ho, Er, Tm, Yb and Lu.

According to the preparation method of the catalytic cracking catalyst provided by the invention, the NSY molecular sieve synthesized by kaolin in situ crystallization can further comprise one or more steps of filtering, washing, drying and roasting after ion exchange, and the steps can refer to the filtering, washing, drying and roasting methods well known to those skilled in the art.

According to the preparation method of the catalytic cracking catalyst, the preparation method of the modified NSY molecular sieve comprises the following steps:

(1) roasting and dehydrating kaolin at 500-900 ℃ to convert the kaolin into metakaolin, and crushing the metakaolin to prepare metakaolin powder with the particle size of less than 10 microns;

(2) adding sodium silicate, guiding agent, sodium hydroxide solution and water into metakaolin powder to prepare Na with the mixture ratio of (1-2.5)₂O：Al₂O₃：(4-9)SiO₂：(40-100)H₂O, wherein the mass ratio of the directing agent to the metakaolin is 0.01-1.0;

(3) crystallizing the reaction raw material A under stirring at 88-98 ℃, supplementing a second silicon source after the crystallization time reaches 1-70h to obtain a reaction raw material B, wherein the second silicon source accounts for 0.1-10 wt% of the total fed silicon amount in terms of silicon oxide;

(4) crystallizing the reaction raw material B under stirring at 88-98 ℃ and recovering a product to obtain NSY molecular sieve synthesized by kaolin in-situ crystallization;

(5) the recovered product is subjected to ion exchange and/or ultra-stabilization treatment.

According to the preparation method of the catalytic cracking catalyst, in the preparation method of the modified NSY molecular sieve, the directing agent can be synthesized according to a conventional method, such as the preparation methods of USP3574538, USP3639099, USP3671191, USP4166099 and EUP 0435625. The molar composition of the directing agent is as follows: (10-17) SiO₂：(0.7-1.3)Al₂O₃：(11-18)Na₂O：(200-350)H₂And O. During synthesis, raw materials are aged at 4-35 ℃, preferably 4-20 ℃ to obtain the directing agent.

The preparation method of the catalytic cracking catalyst comprises the step of preparing the modified NSY molecular sieve, wherein the sodium content of the second silicon source is Na₂From 0.01% to 10% by weight, preferably < 1% by weight, calculated as O. The second silicon source may be a solid silicon source and/or a liquid silicon source. The preferred second silicon source is solid silica gel for cost control reasons. The solid silica gel is counted in the total synthesis proportion, and the adopted solid silica gel can be solid silica gel with different pore diameters. The silica gel is divided by pore size and comprises fine-pore silica gel, coarse-pore silica gel and intermediate-pore silica gel between the fine-pore silica gel and the coarse-pore silica gel. Conventionally, silica gel having an average pore diameter of 1.5 to 2.0nm or less is called fine pore silica gel (e.g., type a solid silica gel of special silica gel factory of Qingdao ocean chemical group), and silica gel having an average pore diameter of 4.0 to 5.0nm or more is called coarse pore silica gel (e.g., type C solid silica gel of special silica gel factory of Qingdao ocean chemical group); silica gel having an average pore diameter of 10.0nm or more is called extra-coarse silica gel, and silica gel having an average pore diameter of 0.8nm or less is called extra-fine silica gel (for example, type B solid silica gel of Qingdao Seawa Seikagaku Seika Seikagaku Seiki Seikagaku Seika Seiki Seikagaku Seika Seikagaku Seika Seikagaku Seika). The second silicon source may also be liquid silica gel, and when liquid silica gel is used as the second silicon source, it is preferable that SiO therein₂The mass content is at least 30 percent.

According to the preparation method of the catalytic cracking catalyst, the second silicon source accounts for 4-10 wt% of the total fed silicon amount in terms of silicon oxide in the preparation method of the modified NSY molecular sieve.

According to the preparation method of the catalytic cracking catalyst provided by the invention, in the preparation method of the modified NSY molecular sieve, sodium silicate and a second silicon source are supplemented into a synthesis preparation system in different processes, and particularly, the second silicon source is added in the crystal growth period. The method combines a method of adding different silicon sources in different stages of a crystallization process to control a synthesis ratio technology and a kaolin in-situ crystallization synthesis technology (natural minerals are used as main aluminum sources and silicon sources), changes a crystal growth environment through the silicon sources, and adopts two completely different material ratios in two stages of a crystal nucleation period and a crystal growth period. The method adopts a larger sodium-silicon ratio (Na) in the material in the crystal nucleation period₂O/SiO₂) Is favorable for the rapid nucleation of the Y-type molecular sieve, and a low-sodium or sodium-free silicon source is added in the crystal growth period to improve the silicon-aluminum ratio (SiO) in the synthetic material₂/A1₂O₃) Simultaneously, the sodium-silicon ratio (Na) in the material is reduced₂O/SiO₂) On the premise of shortening the crystallization time, the method is favorable for improving the silicon-aluminum ratio of the product, and the silicon-aluminum ratio of the framework is improved to 5.0-5.5.

According to the preparation method of the catalytic cracking catalyst provided by the invention, in the preparation method of the modified NSY molecular sieve, the Y-type molecular sieve composite material product with a certain mesopore and macropore is obtained by crystallization under stirring, wherein the crystallization stirring speed can be, but is not limited to, 50-1000 rpm, preferably 300-500 rpm, and the time is 16-48 hours, preferably 24-32 hours. The drying temperature of the crystallized zeolite is 100-120 ℃.

According to the preparation method of the catalytic cracking catalyst provided by the invention, in the step (4) of the preparation method of the modified NSY molecular sieve, a product is recovered after crystallization is finished, and the NSY molecular sieve synthesized by kaolin in-situ crystallization is obtained. The recovery typically includes a filtration step, and optionally may include one or more of washing, drying, and calcining.

The preparation method of the catalytic cracking catalyst, disclosed by the invention, can be used for preparing the modified NSY molecular sieve, wherein the ion exchange in the preparation step (5) can be ammonium ion exchange and/or rare earth ion exchange.

The preparation method of the catalytic cracking catalyst comprises the step of ion exchange of rare earth, wherein the content of rare earth in the modified NSY molecular sieve obtained in the step (5) is RE₂O₃Calculated as 0-20 wt%, and the content of sodium oxide is less than 2 wt%.

In one embodiment, the modified NSY molecular sieve is obtained by subjecting NSY molecular sieve synthesized by kaolin in-situ crystallization to ultra-stabilization treatment and ion exchange treatment, and is called an ion-modified ultra-stable NSY molecular sieve.

The NSY molecular sieve synthesized by kaolin in-situ crystallization is subjected to ultra-stabilization treatment and ion exchange treatment to obtain the ion-modified ultra-stable NSY molecular sieve. The ultra-stabilization treatment such as hydrothermal ultra-stabilization and gas phase ultra-stabilization; the ion exchange is one or more of ammonium ion exchange and rare earth ion exchange. The order of the ultra-stabilization treatment and the ion exchange is not required, and for example, the ultra-stabilization treatment may be performed first and then the ion exchange may be performed, the ion exchange may be performed first and then the ultra-stabilization treatment may be performed, or the ultra-stabilization treatment and the ion exchange may be performed alternately one or more times.

The hydrothermal superstabilization process may be carried out according to the prior art, and in one embodiment, the NSY molecular sieve synthesized by kaolin in situ crystallization may or may not be subjected to ion exchange, and then treated by contacting with water vapor at a temperature of 550-750 ℃ for a contact time of 0.5-20 hours, for example. For example, hydrothermal superstabilization treatment can be performed by a method disclosed in patent documents CN108928833A and CN 108927211A.

The gas phase ultra-stable method can refer to the existing gas phase ultra-stable method, and in one embodiment, NSY molecular sieve which is synthesized by ion exchange or ion exchange-free in-situ crystallization is contacted with silicon tetrachloride gas at 200-600 ℃ for treatment, and the contact time can be 0.5-20 hours, for example. For example, the gas phase ultra-stable treatment can be carried out by the methods disclosed in patent documents CN1382525A, CN1194941A, CN1683244A and CN 111013328A.

Said is separated fromThe ion exchange can be carried out by adopting ammonium salt and/or rare earth salt solution, and the ion exchange can be carried out by referring to the existing ion exchange method, and the invention has no special requirement. In one embodiment, the ion exchange step includes mixing the NSY molecular sieve synthesized by kaolin in-situ crystallization or the NSY molecular sieve synthesized by kaolin in-situ crystallization after hyperstabilization treatment with an exchange solution, and stirring at 20-90 ℃ for 10-120 minutes, wherein the above process may be performed one or more times, and the exchange solution for each exchange may contain ammonium ions, rare earth ions or both ammonium ions and rare earth ions. Preferably, the exchange solution contains ammonium salt and/or rare earth salt, the concentration of ammonium salt in the exchange solution is 5-700g/L, such as 5-100g/L and/or the concentration of rare earth salt is RE₂O₃In the range of 2 to 450g/L, for example 5 to 400g/L or 5 to 200 g/L.

Such as one or more of ammonium chloride, ammonium nitrate, ammonium sulfate.

The rare earth salt is one or more of rare earth chloride and rare earth nitrate.

The rare earth can comprise one or more of lanthanide rare earth and actinide rare earth, for example, one or more of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, TB, Dy, Ho, Er, Tm, Yb and Lu.

Step (5) may further comprise a washing step, wherein the washing step may be carried out by washing with water or ammonium salt to wash out the exchanged sodium ions.

Preferably, the rare earth content of the ion-modified ultrastable NSY molecular sieve obtained in the step (5) is RE₂O₃Calculated as 0-12 wt%, sodium oxide content less than 2 wt%, and unit cell constant of 2.435-2.460 nm. The unit cell constants can be measured by X-ray diffraction.

According to the preparation method of the catalytic cracking catalyst, the ion exchange product obtained in the step (5) of preparing the modified NSY molecular sieve is also roasted.

According to an embodiment of the present invention, the method for preparing the catalytic cracking catalyst includes the steps of:

(S1) obtaining a molecular sieve slurry,

(S2) obtaining a second clay slurry,

(S3) obtaining a zirconium sol,

(S4) obtaining a phosphor-aluminum inorganic binder,

(S5) mixing the molecular sieve slurry, the second clay slurry, the zirconium sol, the aluminophosphate inorganic binder, and optionally the third binder;

(S6) spray-drying the slurry obtained in the step (S5).

The preparation method of the catalytic cracking catalyst comprises the steps of mixing a molecular sieve slurry, a second clay slurry, a zirconium sol, a phosphorus-aluminum inorganic binder and an optional third binder to form a slurry, wherein the solid content of the slurry can be 15-45 wt%, preferably 20-40 wt%; the slurry is then spray dried. The spray drying method may be an existing method.

According to the preparation method of the catalytic cracking catalyst provided by the invention, the catalyst microspheres obtained by spray drying can be washed and/or roasted. There is no particular requirement for the order of washing and calcination. Reference may be made to the washing and calcination methods of the existing catalyst cracking catalysts.

The present invention will be described in detail below by way of examples.

The element content in the catalyst is determined by XRF, and the specific surface area and the pore volume are determined by adopting a low-temperature nitrogen adsorption-desorption method. The abrasion index of the catalyst was measured by RIPP29-90 method in "analytical methods for petrochemicals, RIPP test methods" (edited by Yangchi, scientific Press, 1990).

The specifications of the raw materials used in the preparation of the zirconium sol, the preparation of the molecular sieve and the preparation of the catalyst are as follows:

pseudo-boehmite: commercially available from Shandong aluminum industries, at 75 wt% solids;

zirconium oxychloride: commercially available from Aldrich, analytically pure, at 98.5 wt%;

kaolin: a solid content of 75% by weight, produced by Kaolin corporation of China (Suzhou);

DASY molecular sieve: chinese petrochemical catalyst, Qilu division, Na₂O content 1.02 wt%, rare earth content (in terms of RE)₂O₃Calculated by weight) of 2.3 percent, and the silicon-aluminum ratio (SiO)₂/Al₂O₃Molar ratio) was 10.4.

ZSP-3 molecular sieve: chinese petrochemical catalyst, Qilu division, P₂O₅Is contained in an amount of 3.02 wt.% (SiO)₂/Al₂O₃) Is 45 of Na₂The O content was 0.02% by weight.

Aluminum sol: produced by Shandong aluminum works, and has the solid content of 25 weight percent.

Glacial acetic acid: the analysis of the national medicine group is pure, and the weight percentage is 99 percent.

Ammonia water: the group of traditional Chinese medicines, analytically pure, 28 wt%.

Oxalic acid: the national drug group, analytically pure, 99% by weight

Zirconium isopropoxide: the national drug group, analytically pure, 99% by weight

Triethanolamine: the national drug group, analytically pure, 99% by weight

Sodium hydroxide, national drug group, analytically pure, 99% by weight

Hydrochloric acid: the group of Chinese medicines, analytically pure, 36% by weight

In the examples, the content of NaY zeolite in the composite material was measured by the RIPP146-90 standard method (the RIPP standard method is described in "analytical methods in petrochemical industry (RIPP test method)", Yanggui et al, ed. scientific Press, 1990, the same shall apply hereinafter).

Unit cell constant a₀Determined according to the RIPP145-90 standard method. The framework Si/Al ratio is determined by the unit cell constant a₀Calculated according to the following formula: SiO 2₂/Al₂O₃(molar ratio) 2 × (25.858-a)₀)/(a₀-24.191)。

Nitrogen adsorption method (GB/T58)16-1995) measuring the specific surface area; measuring the pore volume by a nitrogen adsorption method (RIPP151-90), wherein the pores larger than 0.8nm in the nitrogen adsorption method are defined as medium and large pores, and the calculation formula of the medium and large pore ratio is (V)_{General hole}-V_Micro-pores)/V_{General hole}×100％。

In the molecular sieve preparation examples and comparative examples, the preparation of directing agent: 250 kg of sodium silicate solution (containing 20.05% by weight of SiO) are taken₂6.41% by weight of Na₂O), slowly adding 120 kg of sodium metaaluminate solution (containing 3.15 wt% of Al) at 30 ℃ under rapid stirring₂O₃21.1% by weight of Na₂O), stirring for 1 hour, and aging for 48 hours at 20 ℃ to obtain the guiding agent. The guiding agent has the composition of 16Na₂O：Al₂O₃：15SiO₂：320H₂O。

Zirconium Sol preparation example 1

Adding 130g of deionized water into a beaker, then adding 125g of zirconium oxychloride, stirring for 10min, adding 93 acetic acid, and stirring for 30min to obtain a mixed solution; then ammonia water is slowly added into the solution by a peristaltic pump, the pump speed (namely the feeding speed of the ammonia water) is controlled at 5ml/min, the pH value is controlled at 2.5, and clear and transparent zirconium sol A1 is obtained.

Zirconium Sol preparation example 2

Adding 130g of deionized water into a beaker, then adding 125g of zirconium oxychloride, stirring for 10min, adding 70g of oxalic acid, and stirring for 30min to obtain a mixed solution; then slowly adding ammonia water into the solution by using a peristaltic pump, controlling the pump speed at 5ml ammonia water/min and the pH value at 2.5 to obtain clear and transparent zirconium sol A2.

Zirconium Sol preparation example 3

Adding 170g of deionized water into a beaker, then adding 176g of zirconium isopropoxide, stirring for 10min, adding 70g of oxalic acid, and stirring for 30min to obtain a mixed solution; then slowly adding triethanolamine into the solution by a slow pump, controlling the pump speed at 5ml/min and the pH at 2.5 to obtain clear and transparent zirconium sol A3.

Comparative example 1 zirconium Sol preparation

130g of deionized water and 125g of zirconium oxychloride were added to the beaker, the mixture was stirred for 10min, and then ammonia was slowly added to the solution by means of a peristaltic pump at a pump speed of 5ml/min, resulting in a suspension of precipitate having a pH of 1.2 and recorded as D1.

Comparative example 2 zirconium Sol preparation

Adding ZrOCl into the beaker₂·8H₂O35.38 g, 9.77g of 45 wt% sodium hydroxide solution is added according to the molar ratio of Zr to sodium hydroxide of 1:1, then the mixture is stirred for 60min at the temperature of 60 ℃ to obtain a first contact after reaction, and then the first contact is subjected to Zr: H at the temperature of 40 DEG C⁺Adding 19.41g hydrochloric acid with the concentration of 31 weight percent according to the proportion of 1:1.5, stirring for 60min at the temperature of 40 ℃ to obtain a second contact material, and then adding Zr to H at the temperature of 40℃ according to the ratio of Zr to H⁺To the second contact, 19.41g of hydrochloric acid having a concentration of 31 wt% (wt% means wt%) was added at a ratio of 1:1.5, and the mixture was stirred at a temperature of 40 ℃ for 60min to obtain a zirconium sol D2.

Comparative example 3 zirconium Sol preparation

The zirconium sol D1 was prepared according to the preparation method of zirconium sol preparation comparative example 1, dried at 120 ℃/12h, and then calcined at 600 ℃ for 4h to obtain zirconium oxide powder D3.

Zirconium Sol preparation examples 1-3 and zirconium Sol preparation comparative examples 1-3 the properties of the zirconium sols prepared are shown in Table 1.

TABLE 1

Zirconium Sol preparation example No	1	2	3	Comparative example 1	Comparative example 2
						Zirconium Sol numbering	A1	A2	A3	D1	D2
ZrO₂Mass%	10.8	11.9	11.3	13.4	16.3
						pH value	2.5	2.5	2.5	1.2	2.5
Molar ratio of alkali cation to Zr	2	1.67	1.74	0.6	1
						Stabilizer to Zr molar ratio	4	4	4	0	0
Average particle diameter, nm	10	9.8	9.7
						Colloidal particle size range, nm	8-10	8-10	8-10
Concentration degree of%	95	93	92
						Ratio of monoclinic phase to tetragonal phase	0.4:1	0.35:1	0.3:1

Dry at 100 ℃ for 6h and bake the sample at 600 ℃ for 4 h.

Catalyst preparation examples 1 to 3

The catalysts were prepared according to the following procedure, the catalyst formulation being shown in table 2:

(1) preparing phosphor aluminum glue: pulping pseudo-boehmite, kaolin and water to disperse into slurry with solid content of 15 wt% (clay and Al calculated on dry basis)₂O₃The calculated weight ratio of the pseudoboehmite is 1: 1); concentrated phosphoric acid (H) was added to the slurry in a weight ratio of P/Al to 3 with stirring₃PO₄85 wt.%), at 70 ℃ for 30 minutes, to obtain a phospho-alumino-sol.

(2) Firstly, pulping kaolin to obtain kaolin slurry with the solid content of 20 weight percent, taking a DASY molecular sieve and a ZSP-3 molecular sieve, separately adding water for pulping, and dispersing by using a homogenizer to respectively obtain DASY molecular sieve slurry with the solid content of 35 weight percent and ZSP-3 molecular sieve slurry with the solid content of 35 weight percent; mixing kaolin slurry, DASY molecular sieve slurry, molecular sieve slurry and molecular sieve slurry, stirring, and adding acidified aluminum oxide (HCl and Al) with solid content of 10 wt%₂O₃The calculated molar ratio (acid-aluminum ratio) of the pseudo-boehmite is 0.2), stirring for 10min to obtain first catalyst mixed slurry; mixing zirconium sol and phosphorus-aluminum sol, then adding the mixture into the first catalyst mixed slurry, and stirring for 30min to obtain second catalyst slurry; and (3) carrying out spray drying on the second catalyst slurry to obtain catalyst microspheres, roasting the obtained catalyst microspheres for 2 hours at 500 ℃, and washing the catalyst microspheres once by using ammonium sulfate with the catalyst dry basis weight of 6% to obtain the catalytic cracking catalyst.

Catalyst preparation examples 4 to 6 were prepared according to the following methods,

the catalyst formulation is shown in table 2:

(1) preparing phosphor aluminum glue: pulping pseudo-boehmite, kaolin and water to disperse into slurry with solid content of 15 wt% (clay and Al calculated on dry basis)₂O₃Calculated weight ratio of the pseudo-boehmite is 1:1), and concentrated phosphoric acid (concentration is 85 weight percent) is added into the slurry according to the weight ratio of P/Al to 4 under stirring, and the reaction is carried out for 20 minutes at the temperature of 80 ℃ to obtain the phosphor-alumina gel.

(2) Firstly, pulping kaolin to prepare slurry with the solid content of 20 weight percent, taking a DASY molecular sieve and a ZSP-3 molecular sieve, respectively adding water for pulping, and dispersing by using a homogenizer to obtain DASY molecular sieve slurry and ZSP-3 molecular sieve slurry with the solid contents of 35 weight percent; mixing kaolin slurry, DASY molecular sieve slurry and ZSP-3 molecular sieve slurry, stirring, adding acidified aluminum oxide with solid content of 10 wt% (acidified by hydrochloric acid and acid-aluminum ratio of 0.2), and stirring for 10min to obtain slurry containing molecular sieve and kaolin; and mixing the zirconium sol and the phosphorus-aluminum sol, adding the mixture into the slurry containing the molecular sieve and the kaolin, and stirring for 30min to obtain catalyst slurry. And (3) carrying out spray drying on the catalyst slurry, roasting the obtained catalyst microspheres for 2 hours at 500 ℃, and washing the catalyst microspheres once by using ammonium sulfate with the catalyst dry basis weight of 6% to obtain the catalytic cracking catalyst.

TABLE 2

Catalyst numbering	C1	C2	C3	C4	C5	C6	DB1	DB2	DB3	DB4	DB5	DB6
													Kaolin clay	30	30	30	30	40	20	40	40	40	40	40	40
DASY	1	5	9	5	5	5	5	5	5	5	5	5
													ZSP-3	29	25	21	25	20	35	20	20	20	20	20	20
Acidified alundum	5	10	8	10	15	8	30	25	20	15	15	15
													Zirconium Sol numbering	A1	A2	A3	A2	A1	A3		A1		D1	D2	D3
Zirconium sol	5	5	10	20	5	12		5		5	5	5
													Phosphor-aluminum paste	25	17	18	5	10	10			10	10	10	10
Aluminium sol	5	8	4	5	5	10	5	5	5	5	5	5

The formulations in Table 2 are in parts by weight, where the zirconium sol is ZrO₂Acidifying the aluminum and aluminum sols to Al₂O₃The other components are on a dry basis.

Catalyst preparation comparative examples 1 to 6

The catalysts were prepared according to the methods of catalyst preparation examples 4 to 6, and the formulations and the physicochemical properties and the evaluation results of the catalysts are shown in Table 2 and Table 3, respectively.

Evaluation of catalyst:

the catalyst is aged and deactivated for 12 hours at 800 ℃ by 100 percent of water vapor. Evaluation is carried out on fixed fluidized bed micro-reaction ACE, the raw oil is Wu-MI-Sanyuan oil (the composition and physical properties are shown in Table 3), and the evaluation conditions are as follows: the reaction temperature is 550 ℃, the agent-oil ratio (weight) is 6, and the WHSV is 16h^-1. The results are shown in Table 4.

Wherein, the conversion rate is gasoline yield, liquefied gas yield, dry gas yield and coke yield

Selectivity of low carbon olefin (ethylene yield + propylene yield)/conversion

Ethylene concentration ═ ethylene yield/dry gas yield

Propylene concentration ═ propylene yield/liquefied gas yield

TABLE 3

The results in table 4 show that the catalyst for catalytic cracking provided by the present invention has significantly lower wear index, i.e., better wear strength, and further improves the conversion rate, increases the selectivity of low carbon olefins, and increases the concentrations of ethylene and propylene in the catalytic cracking reaction.

Molecular sieves preparation example 1

100 kg of pulverized metakaolin powder, 400 kg of sodium silicate solution (containing 20.05% by weight of SiO) was added with stirring₂6.41% by weight of Na₂O), 60 kg of directing agent and 100 kg of 5% strength by weight sodium hydroxide solution. Heating to 95 ℃, stirring at constant temperature, adding 10 kg of solid silica gel (Qingdao ocean chemical group special silica gel factory, type A) after 8 hours, and crystallizing for 12 hours, wherein the stirring speed is 400 r/min during feeding and crystallizing. After crystallization, the crystallization tank is quenched, filtered and washed by water until the pH value of the washing liquor is less than 10. Drying at 120 deg.C for 2 hr to obtain zeolite material Y-1. Measuring Y-1 by X-ray diffraction method, crystallinity by peak height method, K1 value of ratio of crystallinity by peak height method to crystallinity by peak area method, Si/Al ratio value determined by unit cell constant a0, unit cell constant a₀The K2 value and the mesopore ratio of the measured Si/Al ratio to the chemically measured Si/Al ratio are shown in Table B1.

Molecular sieve preparation example 2

Preparation of molecular sieves example 1, 100 kg of a pulverized metakaolin powder were added with stirring 380 kg of a sodium silicate solution (containing 20.05% by weight of SiO)₂6.41% by weight of Na₂O), 60 kg of directing agent, 100 kg of 5% strength by weight sodium hydroxide solution. Heating to 93 ℃, stirring at constant temperature, adding 15 kg of solid silica gel (Qingdao ocean chemical group special silica gel factory, type A) after 8 hours, and crystallizing for 14 hours, wherein the stirring speed is 400 r/min during feeding and crystallizing. After crystallization, the crystallization tank is quenched, filtered and washed by water until the pH value of the washing liquor is less than 10. Drying at 120 deg.C for 2 hr to obtain zeolite material Y-2. Measuring Y-2 by X-ray diffraction method, crystallinity by peak height method, K1 value of ratio of crystallinity by peak height method to crystallinity by peak area method, Si/Al ratio value determined by unit cell constant a0, and crystalCell constant a₀The K2 value and the mesopore ratio of the measured Si/Al ratio to the chemically measured Si/Al ratio are shown in Table B1.

Molecular sieve preparation example 3

Preparation of molecular sieves example 1, 100 kg of a pulverized metakaolin powder are stirred with 360 kg of a sodium silicate solution (containing 20.05% by weight of SiO)₂6.41% by weight of Na₂O), 60 kg of directing agent, 100 kg of 5% strength by weight sodium hydroxide solution. Heating to 95 ℃, stirring at constant temperature, adding 20 kg of solid silica gel (Qingdao ocean chemical group special silica gel factory, type A) after 8 hours, and crystallizing for 16 hours, wherein the stirring speed is 400 r/min during feeding and crystallizing. After crystallization, the crystallization tank is quenched, filtered and washed by water until the pH value of the washing liquor is less than 10. Drying at 120 deg.C for 2 hr to obtain zeolite material Y-3. Measuring Y-3 by X-ray diffraction method, crystallinity by peak height method, K1 value of ratio of crystallinity by peak height method to crystallinity by peak area method, Si/Al ratio value determined by unit cell constant a0, unit cell constant a₀The K2 value and the mesopore ratio of the measured Si/Al ratio to the chemically measured Si/Al ratio are shown in Table B1.

Molecular sieve preparation comparative example 1

This comparative example illustrates the case where two silicon sources were added to the reaction system at once.

Preparation of molecular sieves example 1, 100 kg of a pulverized metakaolin powder are stirred with 400 kg of a sodium silicate solution (containing 20.05% by weight of SiO)₂6.41% by weight of Na₂O), 60 kg of directing agent, 105 kg of 5% strength by weight sodium hydroxide solution, 10 kg of solid silica gel (Qingdao ocean chemical group special silica gel factory, type a). Heating to 94 ℃, stirring at constant temperature, crystallizing for 24 hours, and stirring at the rotating speed of 400 r/min during feeding and crystallizing. After crystallization, the crystallization tank is quenched, filtered and washed by water until the pH value of the washing liquor is less than 10. Drying at 120 deg.c for 2 hr to obtain zeolite DY-1. DY-1, crystallinity by peak height method, K1 value of ratio of crystallinity by peak height method to crystallinity by peak area method, Si/Al ratio value determined by unit cell constant a0, Si/Al ratio value determined by unit cell constant a0, and chemical methodThe K2 value and the medium-large pore ratio of the determined silicon-aluminum ratio are shown in a table B1. DY-1 has low crystallinity and has mixed crystals.

Molecular sieve preparation comparative example 2

This comparative example illustrates the case where no second silicon source was added.

Preparation of molecular sieves example 1, 100 kg of a pulverized metakaolin powder are stirred with 400 kg of a sodium silicate solution (containing 20.05% by weight of SiO)₂6.41% by weight of Na₂O), 60 kg of directing agent, 100 kg of 5% strength by weight sodium hydroxide solution. Heating to 94 ℃, stirring at constant temperature, crystallizing for 24 hours, and stirring at the rotating speed of 400 r/min during feeding and crystallizing. After crystallization, the crystallization tank is quenched, filtered and washed by water until the pH value of the washing liquor is less than 10. Drying at 120 deg.C for 2 hr to obtain zeolite DY-2. DY-2 measured by an X-ray diffraction method, crystallinity by a peak height method, K1 value of a ratio of crystallinity by the peak height method to crystallinity by a peak area method, Si/Al ratio value measured by a unit cell constant a0, K2 value of a ratio of Si/Al ratio value measured by a unit cell constant a0 to Si/Al ratio value measured by a chemical method, and mesoporosity are shown in Table B1. DY-2 has a poor crystallinity but a low Si/Al ratio.

TABLE B1

Catalyst preparation example B1

(1) Preparation of ion-modified ultrastable NSY molecular sieve:

according to SiCl₄: y-1 molecular sieve 0.4 on a dry basis: 1, carrying out contact reaction on the Y-1 molecular sieve prepared in the molecular sieve preparation example 1 and silicon tetrachloride gas at the reaction temperature of 450 ℃ for 2 hours, washing and filtering to obtain a gas-phase ultra-stable NSY type molecular sieve CY-1 with a unit cell constant of 2.456; adding deionized water into the CY-1 molecular sieve for pulping to form CY-1 molecular sieve slurry with the solid content of 10 weight percent; adding water into lanthanum chloride for pulping to form La₂O₃A 5% by weight lanthanum chloride solution; adding lanthanum chloride solution into CY-1 molecular sieve slurry, and adding lanthanum chloride (in La form)₂O₃Calculated) and the molecular sieve (calculated on a dry basis) in a weight ratio of 1:20, stirring for 1h at 70 ℃, filtering, washing, drying for 8h at 150 ℃, and roasting for 4h at 500 ℃; and washing with an ammonium sulfate solution, wherein the weight ratio of ammonium sulfate to the molecular sieve dry basis is 1:20, marking the obtained molecular sieve as UNSY-1;

(2) preparing phosphor aluminum glue: pulping pseudo-boehmite, kaolin and water to prepare slurry with the solid content of 15 wt%, adding concentrated phosphoric acid (the concentration is 85 wt%) into the slurry according to the weight ratio of P/Al to 3 under stirring, and reacting at the temperature of 70 ℃ for 30 minutes to obtain the phosphor-aluminum glue;

(3) preparing a catalyst: according to the catalyst formulation in table B2, kaolin was slurried to produce a kaolin slurry having a solids content of 20 wt%; taking rare earth modified ultrastable NSY molecular sieves UNSY-1 and ZSP-3 molecular sieves, separately adding water, pulping, and dispersing by using a homogenizer to obtain UNSY-1 molecular sieve slurry with the solid content of 35 weight percent and ZSP-3 molecular sieve slurry with the solid content of 35 weight percent; mixing kaolin slurry, UNSY-1 molecular sieve slurry and ZSP-3 molecular sieve slurry, stirring, adding acidified aluminum oxide with the solid content of 10 wt% (the acid-aluminum ratio is 0.2 mol ratio), stirring for 10min, adding zirconium sol A1 and the above-mentioned phosphorus-aluminum adhesive, stirring for 30min, spray drying to obtain catalyst microspheres, and roasting the obtained catalyst microspheres at 500 ℃ for 2 hours to obtain the catalytic cracking catalyst BC 1.

Catalyst preparation examples B2-B3

Prepared according to the method of catalyst example 1, and the catalyst formulation is shown in table B2.

Catalyst example B4

(1) Preparation of ion-modified ultrastable NSY molecular sieve example 4:

the molecular sieve prepared in NSY molecular sieve preparation example 1 is calcined for 12 hours at 650 ℃ under 100 volume percent of water vapor to obtain the ultra-stable NSY type molecular sieve which is recorded as CY-4 and has a unit cell constant of 2.455 nm; adding deionized water into a CY-4 molecular sieve for pulping to obtain slurry with the solid content of 10 weight percent, adding water into lanthanum chloride for pulping to form La₂O₃Adding 5 wt% lanthanum chloride solution into CY-4 molecular sieve slurry, and adding lanthanum chloride (as La) into the slurry₂O₃Calculated) and the molecular sieve (calculated on a dry basis) in a weight ratio of 1:20, stirring for 1h at 70 ℃, filtering, washing, drying for 8h at 150 ℃, and roasting for 4h at 500 ℃. Obtaining the rare earth modified ultrastable NSY molecular sieve, adding an ammonium sulfate solution, and washing, wherein the weight ratio of ammonium sulfate to the molecular sieve dry basis is 1:20, the molecular sieve obtained is designated U-NSY 4.

(2) Preparing phosphor aluminum glue: pulping pseudo-boehmite, kaolin and water to disperse into slurry with solid content of 15 wt% (clay and Al calculated on dry basis)₂O₃The weight ratio of the alumina source is 1:1), adding concentrated phosphoric acid according to the weight ratio of P/Al to 4 into the slurry under stirring, and stirring for 20 minutes at the temperature of 80 ℃ to react to obtain the phosphorus-aluminum sol.

(3) Preparing a catalyst: according to the formula of the catalyst in the table 1, firstly pulping kaolin, wherein the solid content of the obtained kaolin slurry is 40 weight percent, and adding alumina sol for pulping; respectively adding water into a rare earth modified NSY molecular sieve and a ZSP-3 molecular sieve for pulping, and dispersing by using a homogenizer to obtain NSY molecular sieve slurry and ZSP-3 molecular sieve slurry with the solid contents of the slurries being 35 weight percent respectively; mixing and stirring kaolin slurry, NSY molecular sieve slurry and a ZSP-3 molecular sieve, then adding the phosphorus-aluminum sol obtained in the step (2), and stirring for 10 min. And finally, adding the alumina sol into the catalyst mixed slurry, stirring for 30min, spray drying, and roasting the obtained catalyst microspheres at 500 ℃ for 2 hours to obtain the catalytic cracking catalyst BC 4.

Catalyst preparation examples B5-B6

Catalysts were prepared according to the method of catalyst preparation example B4, with the formulation shown in table B2, wherein a modified NSY molecular sieve was prepared, according to the method of example B4, except that the rare earth content was varied.

Catalyst preparation comparative examples B1, B2

Prepared according to the method of catalyst preparation example B4, the catalyst formulation is shown in table B2. Wherein the modified NSY molecular sieve is corresponding to the modified molecular sieve obtained by modifying the molecular sieve of the comparative example for preparing the molecular sieve.

Evaluation of catalyst:

the catalyst is aged by 100% water vapor at 800 DEG CThe inactivation treatment was carried out for 12 hours. Evaluation is carried out on fixed fluidized bed micro-reaction ACE, the raw oil is Wu-MI-Sanyuan oil (the composition and physical properties are shown in Table 3), and the evaluation conditions are as follows: the reaction temperature is 550 ℃, the agent-oil ratio (weight) is 6, and WHSV is 16h^-1. The results are set forth in Table B3.

Low carbon olefin selectivity (propylene + ethylene) yield/conversion × 100%

TABLE B3

Catalyst and process for preparing same	BC1	BC2	BC3	BC4	BC5	BC6	BDB5	BDB6
									Abrasion index, m%/h	0.8	0.6	0.7	0.6	0.9	1	3.9	4.8
Product distribution/weight%
									Dry gas	4.93	4.79	4.48	4.35	4.55	5.28	4.25	4.58
Liquefied gas	35.97	36.85	35.66	34.44	34.51	36.41	32.55	33.27
									Ethylene	2.29	2.25	2.02	1.91	1.73	2.45	1.55	1.62
Propylene (PA)	19.58	19.52	18.83	18.16	17.92	22.35	14.63	14.27
									C₅ ⁺Gasoline (gasoline)	31.46	35.03	34.67	33.94	32.93	32.42	29.67	28.71
Circulating oil	12.35	9.02	9.81	10.99	11.33	10.24	14.21	14.13
									Oil slurry	10.11	8.13	9.15	9.85	10.86	9.04	11.87	11.77
Coke	5.18	6.18	6.23	6.43	5.82	6.61	7.45	7.54
									Conversion rate	77.54	82.85	81.04	79.16	77.81	80.72	73.92	74.1
Selectivity of low carbon olefin	28.20	26.28	25.73	25.35	25.25	30.72	21.89	21.44
									Propylene concentration	54.43	52.97	52.80	52.73	51.93	61.38	44.95	42.89
Ethylene concentration	46.45	46.97	45.09	43.91	38.02	46.40	36.47	35.37
									Coke selectivity	6.68	7.46	7.69	8.12	7.48	8.19	10.08	10.18

									Factor of coke	1.50	1.28	1.46	1.69	1.66	1.58	2.63	2.64

Coke factor (coke formation factor) ═ coke yield x (1-conversion)/conversion x 100.

As can be seen from Table B3, the catalytic cracking catalyst provided by the invention has a significantly smaller wear index, i.e., high strength, and when used in catalytic cracking reactions, the conversion rate is improved, the selectivity of low-carbon olefins is increased, the concentrations of propylene and ethylene are increased, the selectivity of coke is improved, and the coke factor is reduced.

As can be seen from tables 4 and B3, the use of the modified NSY molecular sieve has lower coke selectivity than the use of other Y molecular sieves, with other compositions being close. The catalyst has higher activity and the concentration of propylene in liquefied gas is higher.

Claims

1. A catalytic cracking catalyst for increasing the yield of light olefins, comprising: 10-60% by weight on a dry basis of cracking active components, 20-60% by weight on a dry basis of binders, 0-70% by weight on a dry basis of second clays; wherein the binder comprises 1-50 wt% of zirconium sol, 50-99 wt% of phosphorus-aluminum inorganic binder and 0-45 wt% of third binder on a dry basis, based on the dry basis weight of the binder;

the zirconium sol: including 0.5 to 20 mass% of ZrO₂The zirconium sol comprises a stabilizer, alkali cations and water, wherein the molar ratio of the stabilizer to Zr is 1-6, and the pH value of the zirconium sol is 1-7;

2. The catalytic cracking catalyst of claim 1, wherein the third binder is one or more selected from the group consisting of silica sol, alumina sol, silica-alumina gel, acidified aluminum oxide, and metal-modified aluminum oxide.

3. The catalytic cracking catalyst of claim 1, wherein the first molecular sieve is one or more of an MFI structure molecular sieve, a BEA structure molecular sieve, and a mordenite.

4. The catalytic cracking catalyst of claim 1, wherein the second molecular sieve is a Y-type molecular sieve, and the Y-type molecular sieve has a rare earth content of 0 to 20 wt%, preferably 0 to 12 wt%.

5. The catalytic cracking catalyst of claim 1 or 4, wherein the Y-type molecular sieve is one or more of DASY molecular sieve, rare earth-containing DASY molecular sieve, USY molecular sieve, rare earth-containing USY molecular sieve, REY molecular sieve, HY molecular sieve, REHY molecular sieve and modified kaolin in-situ crystallization synthesized Y-type molecular sieve.

6. The catalytic cracking catalyst of claim 1 or 5, wherein the second molecular sieve is an ionically-modified ultrastable NSY molecular sieve; the content of the ion-modified ultrastable NSY molecular sieve in the catalytic cracking catalyst is preferably 1-10 wt% based on the weight of the catalytic cracking catalyst.

7. The catalytic cracking catalyst of claim 1, wherein the second clay is one or more of kaolin, montmorillonite, diatomaceous earth, halloysite, pseudohalloysite, saponite, rectorite, sepiolite, attapulgite, hydrotalcite, and bentonite; the first clay is one or more of kaolin, montmorillonite, diatomite, halloysite, pseudohalloysite, saponite, rectorite, sepiolite, attapulgite, hydrotalcite and bentonite, and the first clay is preferably one or more of kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomite.

8. The catalytic cracking catalyst of claim 1, wherein the preparation method of the phosphorus-aluminum inorganic binder comprises:

9. The catalytic cracking catalyst of claim 8, wherein the phosphorus-aluminum inorganic binder comprises 15 to 35 wt% of Al derived from the alumina source₂O₃50-75% by weight of P₂O₅And 0-35 wt% first clay, e.g., 5-30 wt% first clay, on a dry basis.

10. A catalytic cracking catalyst according to claim 1 or 8, wherein the P/Al weight ratio is 2 to 5.

11. The catalytic cracking catalyst of claim 8, wherein the alumina source is one or more of rho-alumina, chi-alumina, eta-alumina, gamma-alumina, kappa-alumina, delta-alumina, theta-alumina, gibbsite, surge flash, nordstrandite, diaspore, boehmite and pseudo-boehmite.

12. The catalytic cracking catalyst according to claim 1, wherein the zirconium sol has a particle size of 5nm to 15nm, an average particle diameter of 10 ± 2nm, and a concentration of 90% or more.

13. Zirconium sol according to claim 1 or 12, characterized in that it is dried at 100 ℃ for 6h and calcined at 600 ℃ for 2-6 hours for a heat treatment, the product obtained coexisting monoclinic and tetragonal phases, the ratio of monoclinic to tetragonal phases preferably being 0.05-0.6: 1; and/or drying the zirconium sol at 100 ℃ for 6h, roasting at 800 ℃ for 2-6 h, and carrying out heat treatment on the zirconium sol to obtain a product containing ZrO₂Exist in tetragonal phase.

14. The catalytic cracking catalyst of claim 1, wherein the stabilizer is one or more of glycolic acid, oxalic acid, acetic acid, malonic acid, malic acid, tartaric acid, succinic acid, adipic acid, maleic acid, itaconic acid, and citric acid.

15. The catalytic cracking catalyst according to claim 1, wherein the alkali cation is an ammonium ion or a nitrogen-containing cation formed by hydrolysis of a water-soluble organic base such as one or more of methylamine, dimethylamine, trimethylamine, triethylamine, ethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, monomethyl triethylammonium hydroxide, monomethyl triethanolammonium hydroxide, monomethyl tributylammonium hydroxide, etc.

16. The catalytic cracking catalyst of claim 1, wherein the molar ratio of alkali cation to Zr is 1 to 8.

17. The catalytic cracking catalyst according to claim 1, wherein the zirconium sol further contains an inorganic acid group and/or an alcohol, and the molar ratio of the inorganic acid group and/or the alcohol to Zr is 1 to 6: 1; preferably, the inorganic acid radical is one or more of sulfate radical, chloride ion and nitrate radical, and the alcohol is one or more of methanol, ethanol, propanol and butanol.

18. The zirconium sol of claim 1, wherein the zirconium sol has a pH of 2 to 4.

19. The catalytic cracking catalyst according to claim 1, wherein the zirconium sol is prepared by a preparation method comprising the steps of:

(1) preparing a zirconium source solution from ZrO₂The concentration of the zirconium source solution is 0.5-20 mass%;

(2) adding a stabilizer into the zirconium source solution to obtain a first mixed solution; wherein the molar ratio of the stabilizer to zirconium is 1-6:

20. The catalytic cracking catalyst of claim 1, wherein the modified NSY molecular sieve is prepared by a method comprising the steps of:

(5) the NSY molecular sieve synthesized by kaolin in-situ crystallization is subjected to ion exchange and/or ultra-stabilization treatment.

21. A process for preparing a catalytic cracking catalyst according to any one of claims 1 to 20, which comprises: the cracking reactive component, binder, water and optionally clay are slurried and spray dried.

22. A process for preparing a catalytic cracking catalyst according to claim 21, comprising the steps of:

(S1) obtaining a molecular sieve slurry,

(S2) obtaining a second clay slurry,

(S3) obtaining a zirconium sol,

(S4) obtaining a phosphor-aluminum inorganic binder,

(S6) spray-drying the slurry obtained in the step (S5).

23. A catalytic cracking process comprising the step of contacting heavy oil with the catalytic cracking catalyst of any one of claims 13 to 20 for reaction.