Composite material, catalytic cracking catalyst and preparation method thereof

Abstract

The present invention relates to the field of catalysts and discloses a composite material, a catalytic cracking catalyst, and a preparation method thereof. The composite material comprises zirconium sol and a silicon-aluminum material. Based on the total amount of the composite material, on a dry basis, the zirconium sol content is 30-80% by weight, and the silicon-aluminum content is 20-70% by weight. The catalytic cracking catalyst prepared by the present invention using a Y-type molecular sieve and / or a Y-type molecular sieve modified with a rare earth element, the composite material, an aluminum-based binder, and clay has improved catalytic activity. When the catalyst is used in a catalytic cracking reaction, the catalyst has improved wear resistance, lower coke selectivity, higher heavy oil conversion rate and total liquid yield, and stronger resistance to metal contamination.

Description

Technical Field

[0001] The present invention relates to the field of catalysts, and in particular to a composite material, a catalytic cracking catalyst and a preparation method thereof. Background Art

[0002] Catalytic cracking (FCC) is an important secondary crude oil processing process that plays a pivotal role in the oil refining industry. In the FCC process, heavy fractions such as vacuum distillate or even heavier residual oil react in the presence of a catalyst to convert them into high-value-added products such as liquefied petroleum gas, gasoline, and diesel. This process typically requires a catalyst with high cracking activity.

[0003] CN102211039A discloses a catalytic cracking catalyst and its preparation method. The method comprises mixing a molecular sieve, zirconium oxide powder, and an aluminum binder, adding the zirconium oxide powder to the slurry, adjusting the pH of the slurry to 2-5 with an inorganic acid, and then spray drying. The zirconium oxide powder is prepared by mixing an aqueous solution of a zirconium salt with aqueous ammonia. However, this method introduces zirconium in the form of an oxide, which affects the strength of the catalyst. The resulting catalyst also has high coke selectivity, low heavy oil conversion, and poor metal resistance.

[0004] CN103506154A discloses a catalytic cracking catalyst comprising 10-50 wt% (on a dry basis) of a modified Y-type molecular sieve, 0-30 wt% (on a dry basis) of another molecular sieve, 10-70 wt% (on a dry basis) of clay, and 10-40 wt% (on a dry basis) of an inorganic oxide binder. The modified Y-type molecular sieve has a unit cell constant of 2.420-2.440 nm, and, by weight percentage, P is 0.05-6 wt%, RE2O3 is 0.03-10 wt%, alumina is less than 22 wt%, and the specific hydroxyl density is less than 0.35 mmol / g. However, the catalyst produced by this method also has a relatively high coke selectivity, poor heavy oil conversion, and poor metal resistance. Summary of the Invention

[0005] The purpose of the present invention is to overcome the problems of low strength, high coke selectivity, low heavy oil conversion rate and poor metal resistance of existing catalytic cracking catalysts, and to provide a composite material, a catalytic cracking catalyst and a preparation method thereof. The catalyst has better anti-wear performance, lower coke selectivity, higher heavy oil conversion rate and better resistance to metal pollution.

[0006] Currently, most catalytic cracking catalysts are prepared using alumina sol and pseudo-boehmite as binders. However, the binding properties of alumina sol and pseudo-boehmite are poor, which affects the strength and catalytic activity of the catalysts. To address this issue, the inventors of the present invention have discovered that a catalytic cracking catalyst prepared using Y-type molecular sieves and / or Y-type molecular sieves modified with rare earth elements, zirconium sol, silica-alumina materials, aluminum-based binders, and clay exhibits improved wear resistance, lower coke selectivity, higher heavy oil conversion, and greater resistance to metal contamination.

[0007] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides a composite material, which includes zirconium sol and silicon-aluminum material. Based on the total amount of the composite material, on a dry basis, the content of zirconium sol is 30-80 weight%, and the content of silicon-aluminum material is 20-70 weight%.

[0008] A second aspect of the present invention provides a catalytic cracking catalyst comprising a molecular sieve, an aluminum-based binder, clay, and the composite material according to the first aspect of the present invention, wherein, based on the total amount of the catalyst, the molecular sieve content is 10-70% by weight, the aluminum-based binder content is 5-30% by weight, the clay content is 10-70% by weight, and the composite material content is 6-50% by weight;

[0009] The molecular sieve comprises a first molecular sieve and an optional second molecular sieve, wherein the content of the first molecular sieve is 70-100% by weight and the content of the second molecular sieve is 0-30% by weight based on the total amount of the molecular sieve;

[0010] The first molecular sieve is a Y-type molecular sieve, wherein the content of rare earth elements in the Y-type molecular sieve is 0-20% by weight; the second molecular sieve is a molecular sieve with a five-membered ring structure.

[0011] A third aspect of the present invention provides a method for preparing a catalytic cracking catalyst, comprising: mixing a molecular sieve, the composite material according to the first aspect of the present invention or a zirconium sol and a silica-alumina material forming the composite material, an aluminum-based binder, and clay, and then sequentially drying and calcining the mixture to obtain a catalytic cracking catalyst;

[0012] The molecular sieve, composite material, aluminum-based binder and clay are used in such amounts that, based on the total amount of the catalyst, the molecular sieve content is 10-70% by weight, the composite material content is 6-50% by weight, the aluminum-based binder content is 5-30% by weight, and the clay content is 10-70% by weight;

[0013] The molecular sieve comprises a first molecular sieve and an optional second molecular sieve, wherein the content of the first molecular sieve is 70-100% by weight and the content of the second molecular sieve is 0-30% by weight based on the total amount of the molecular sieve;

[0014] The first molecular sieve is a Y-type molecular sieve, wherein the content of rare earth elements in the Y-type molecular sieve is 0-20% by weight; the second molecular sieve is a molecular sieve with a five-membered ring structure.

[0015] Through the above technical solution, the catalytic cracking catalyst prepared by the present invention using Y-type molecular sieve and / or Y-type molecular sieve modified with rare earth elements, composite materials (including zirconium sol and silicon-aluminum materials), aluminum-based binders and clay has better catalytic activity. When the catalyst is used in a catalytic cracking reaction, the catalyst has better anti-wear performance, lower coke selectivity, higher heavy oil conversion rate and total liquid yield, and stronger resistance to metal pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the TEM image of the zirconium sol A1 prepared in Preparation Example I-1 of the present invention. DETAILED DESCRIPTION

[0017] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0018] As mentioned above, the first aspect of the present invention provides a composite material, which includes zirconium sol and silicon-aluminum material. The weight ratio of zirconium sol to silicon-aluminum material is 30-80:20-70 on a dry basis.

[0019] According to the present invention, preferably, on a dry basis, the weight ratio of the zirconium sol to the silicon-aluminum material is 30-75:25-70. In this preferred embodiment, the catalytic activity of the catalyst is more improved.

[0020] According to the present invention, preferably, the particle size of the zirconium sol is between 5-15nm, the average particle size is 8-12nm, and the concentration is above 90%. The particle size described in the present invention refers to the diameter of the largest circumscribed circle in the particle projection diagram, and the average particle size is the arithmetic mean of the sample particle size. In the present invention, the concentration refers to the ratio of the number of particles with a particle size of about 10nm in the measured particles in the zirconium sol sample to the total number of measured particles, which can be obtained by obtaining the zirconium sol sample image through TEM and then by computer image analysis. The about 10nm described in the present invention refers to 10±2nm.

[0021] According to the present invention, preferably, the method for preparing the zirconium sol comprises:

[0022] (a) mixing a solution containing a zirconium source with an acid to obtain a first mixed solution;

[0023] (b) adding an alkaline solution to the first mixed solution to obtain a zirconium sol.

[0024] In the present invention, there are no particular limitations on the method for mixing the zirconium source and the solvent to prepare the solution containing the zirconium source in step (a), as long as a uniform and stable solution can be obtained. Preferably, the mixing is performed at room temperature, such as 20°C, under stirring. The present invention does not particularly limit the equipment used to achieve the stirring conditions, and those skilled in the art can select the appropriate one based on actual needs. The present invention allows for a wide range of solvents to be selected; to save costs, water is preferred, and deionized water is more preferred.

[0025] According to the present invention, preferably, in step (a), the concentration of the solution containing the zirconium source is 0.5-20 wt % calculated as ZrO 2 .

[0026] According to the present invention, since the zirconium source readily undergoes hydrolysis in aqueous solution, a low pH value of the solution limits the reaction and makes it difficult to form a zirconium sol. While adding an alkaline solution can adjust the pH of the solution, directly adding the alkaline solution can easily cause sol particle precipitation. To suppress the reaction rate, an acid is added to control the precipitation rate, thereby generating a stable zirconium sol. Preferably, in step (a), the molar ratio of the zirconium source solution to the acid, calculated as Zr element, is 1:1-6.

[0027] The present invention does not particularly limit the mixing conditions of step (a), and those skilled in the art can select as needed according to actual conditions. The mixing of the present invention is carried out under stirring conditions, and the present invention does not particularly limit the stirring conditions, and those skilled in the art can select as needed according to actual conditions.

[0028] According to the present invention, the acid selected in step (a) has a wide range of options. Preferably, the acid is an organic acid, more preferably at least one of a monobasic acid, a dibasic acid, and a tribasic acid, more 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, and citric acid, with acetic acid and / or citric acid being most preferred. In the present invention, the acid radical ions in the organic acid act as ligands, thereby generating a polymer containing a coordinating group. This polymer then undergoes a hydrolysis reaction to form a three-dimensional spatial network structure, which is connected and thereby slows down hydrolysis and polycondensation. When Zr-O-Zr bonds are formed, a zirconium sol with improved bonding properties is formed.

[0029] According to the present invention, the selection range of the zirconium source in step (a) is relatively wide. Preferably, the zirconium source is an inorganic zirconium salt and / or an organic zirconium salt.

[0030] The present invention has a wide range of selection for the inorganic zirconium salt. Preferably, the inorganic zirconium source is selected from at least one of zirconium tetrachloride, zirconium oxychloride, zirconium acetate, zirconium nitrate, zirconyl nitrate, zirconyl sulfate and zirconyl carbonate.

[0031] The present invention has a wide range of selection for the organic zirconium salt. Preferably, the organic zirconium salt is selected from at least one of zirconium n-propoxide, zirconium isopropoxide, zirconium ethoxide and zirconium butoxide.

[0032] According to the present invention, preferably, the amount of alkali solution added in step (b) is such that the pH value of the zirconium sol is 1-7, preferably 1.5-5, and more preferably 2-3.

[0033] The present invention does not particularly limit the method for adding the alkali solution to the first mixed liquid, as long as the pH value of the zirconium sol satisfies the aforementioned conditions. Preferably, the alkali solution is added to the first mixed liquid using a pump. In the present invention, the alkali solution can be added to the first mixed liquid by controlling the pump speed, i.e., the alkali solution addition rate. The present invention does not particularly limit the pump speed, and those skilled in the art can select the desired pump speed based on actual conditions.

[0034] In the present invention, the alkali solution of step (b) can be selected from a wide range. Preferably, the alkali solution is aqueous ammonia and / or a water-soluble organic base. Further preferably, the water-soluble organic base is an organic amine and / or an organic alcoholamine, more preferably at least one selected from methylamine, dimethylamine, trimethylamine, methanolamine, dimethanolamine, trimethanolamine, triethylamine, ethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, monomethyltriethylammonium hydroxide, monomethyltriethanolammonium hydroxide, and monomethyltributylammonium hydroxide.

[0035] The preparation method of the zirconium sol of the present invention can be summarized as first mixing a solution containing a zirconium source with an acid and then mixing it with an alkaline solution. The zirconium sol prepared by the present invention using the above-mentioned specific preparation method has the characteristics of small colloid particles, concentrated distribution, many surface hydroxyl groups, and good bonding performance.

[0036] According to the present invention, preferably, the expression of the silicon-aluminum material is (0-1)Na2O·(15-50)Al2O3·(85-50)SiO2 in terms of the weight ratio of the oxides.

[0037] According to the present invention, preferably, the average pore size of the silicon-aluminum material is 10-100 nm, and the specific surface area is 150-600 m 2 / g, pore volume of 0.5-1.5cm 3 In the present invention, the average pore size, specific surface area and pore volume of the silicon-aluminum material are measured by low-temperature nitrogen adsorption-desorption method.

[0038] According to the present invention, preferably, the method for preparing the silicon-aluminum material comprises:

[0039] (i) mixing a silicon source with an aluminum source to obtain a mixture containing the silicon source and the aluminum source;

[0040] (ii) adding an alkaline solution to the mixture containing the silicon source and the aluminum source to obtain a slurry, and then aging the slurry to obtain a solid precipitate;

[0041] (iii) contacting the solid precipitate with an ammonium salt or an acid to obtain a silica-alumina material.

[0042] The present invention has no particular limitation on the manner of mixing the silicon source and the aluminum source in step (i). Preferably, the silicon source is added to the aluminum source.

[0043] According to the present invention, preferably, in step (i), the molar ratio of the silicon source calculated as SiO2 to the aluminum source calculated as Al2O3 is 50-85:50-15.

[0044] According to the present invention, preferably, the mixing conditions in step (i) include: a temperature of 20-95°C.

[0045] The present invention allows for a wide range of choices for the silicon source. Preferably, the silicon source is an alkaline silicon source, more preferably one or more of alkaline silica sol, water glass, sodium silicate, and an alkaline hydrolysis product of a silicon metal alkoxide. In the present invention, the alkaline hydrolysis product of a silicon metal alkoxide refers to a hydrolysis product of a silicon metal alkoxide under alkaline conditions, such as methyl orthosilicate, tetraethyl silicate, isopropyl orthosilicate, and butyl orthosilicate.

[0046] The present invention allows for a wide range of choices for the aluminum source. Preferably, the aluminum source is an acidic aluminum source, more preferably one or more of aluminum sulfate, aluminum chloride, aluminum sol, and an acidic hydrolysis product of an aluminum metal alkoxide. In the present invention, the acidic hydrolysis product of an aluminum metal alkoxide refers to a hydrolysis product of an aluminum metal alkoxide under acidic conditions, such as aluminum isopropoxide, aluminum sec-butoxide, and aluminum triethoxide.

[0047] According to the present invention, preferably, the amount of alkali solution added in step (ii) is such that the pH value of the slurry is 8-10.5.

[0048] According to the present invention, preferably, the aging conditions in step (ii) include: a temperature of 50-95° C. and a time of 1-10 h.

[0049] The present invention has a wide range of selection for the alkali solution in step (ii). Preferably, the alkali solution is selected from at least one of ammonia water, sodium hydroxide solution, potassium hydroxide solution and sodium metaaluminate solution.

[0050] It should be noted that when the alkaline solution in step (ii) is a sodium metaaluminate solution, it is necessary to deduct the aluminum in the sodium metaaluminate when the silicon source is added to the aluminum source according to a specific molar ratio in step (i).

[0051] According to a preferred embodiment of the present invention, in step (iii), the solid precipitate is contacted with the ammonium salt by mixing the solid precipitate with the ammonium salt and water to perform ammonium exchange.

[0052] In the present invention, preferably, the weight ratio of the solid precipitate to the ammonium salt and water on a dry basis is 1:0.05-0.1:5-30.

[0053] According to the present invention, preferably, the ammonium exchange conditions are such that the sodium content of the silicon-aluminum material is less than 1 wt%.

[0054] Further preferably, the conditions for the ammonium exchange include: a temperature of 20-100° C., 1-3 exchanges, and a time of 0.5-1 h for each exchange.

[0055] The present invention has a wide range of choices for the ammonium salt. Preferably, the ammonium salt is selected from at least one of ammonium chloride, ammonium sulfate, ammonium nitrate, ammonium carbonate and ammonium bicarbonate.

[0056] According to another preferred embodiment of the present invention, in step (iii), the solid precipitate is contacted with the acid by mixing the solid precipitate with the acid and water for acid treatment.

[0057] In the present invention, preferably, the weight ratio of the solid precipitate to the acid and water on a dry basis is 1:0.03-0.3:5-30.

[0058] According to the present invention, preferably, the acid treatment conditions are such that the sodium content of the silicon-aluminum material is less than 1 wt%.

[0059] Further preferably, the acid treatment conditions include: a temperature of 20-100° C., a time of at least 0.5 h, more preferably 1-3 h;

[0060] The present invention has a wide range of choices for the acid. Preferably, the acid is selected from at least one of sulfuric acid, hydrochloric acid and nitric acid.

[0061] In the present invention, before the solid precipitate is contacted with the ammonium salt or acid in step (iii), the solid precipitate may be dried or not. The present invention has no particular limitation on the drying method, which may be a conventional choice in the art.

[0062] A second aspect of the present invention provides a catalytic cracking catalyst comprising a molecular sieve, an aluminum-based binder, clay, and the composite material according to the first aspect of the present invention, wherein, based on the total amount of the catalyst, the molecular sieve content is 10-70% by weight, the aluminum-based binder content is 5-30% by weight, the clay content is 10-70% by weight, and the composite material content is 6-50% by weight;

[0063] The molecular sieve comprises a first molecular sieve and an optional second molecular sieve, wherein the content of the first molecular sieve is 70-100% by weight and the content of the second molecular sieve is 0-30% by weight based on the total amount of the molecular sieve;

[0064] The first molecular sieve is a Y-type molecular sieve, wherein the content of rare earth elements in the Y-type molecular sieve is 0-20% by weight; the second molecular sieve is a molecular sieve with a five-membered ring structure.

[0065] In the present invention, the physicochemical properties and preparation method of the zirconium sol involved in the composite material, and the physicochemical properties and preparation method of the silicon-aluminum material are as described above and will not be repeated here.

[0066] According to the present invention, preferably, the Y-type molecular sieve is at least one of HY molecular sieve, REY molecular sieve, NSY molecular sieve, REHY molecular sieve, USY molecular sieve, REUSY molecular sieve, DASY molecular sieve and REDASY molecular sieve.

[0067] More preferably, the first molecular sieve is a REY molecular sieve and / or a rare earth element-modified NSY molecular sieve. In this preferred embodiment, the catalytic cracking activity of the catalyst can be further enhanced, thereby further improving the catalyst strength, heavy oil conversion rate, and metal contamination resistance, while reducing coke selectivity.

[0068] According to the present invention, preferably, the content of the rare earth element in the NSY molecular sieve is 10-20% by weight.

[0069] The present invention has a wide range of selection for the rare earth elements. Preferably, the rare earth elements may include one or more of lanthanides and actinides, and further preferably at least one of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, and more preferably La.

[0070] According to the present invention, preferably, the rare earth element modified NSY molecular sieve is prepared by a two-crosslinking and two-calcining method, specifically: mixing a solution containing the NSY molecular sieve with a solution containing the rare earth element, and then drying and calcining the obtained mixed solution in sequence; repeating the above steps to obtain the rare earth element modified NSY molecular sieve.

[0071] In the present invention, the solution containing NSY molecular sieves and the solution containing rare earth elements are mixed by adding the solution containing rare earth elements to the solution containing NSY molecular sieves. The present invention does not particularly limit the method for forming the solution containing NSY molecular sieves or the solution containing rare earth elements, as long as a uniform and stable mixed solution can be obtained. The mixing is performed under stirring conditions.

[0072] The present invention has no particular limitation on the mixing conditions, as long as the rare earth element content in the NSY molecular sieve is 10-20 wt%. Preferably, the mixing conditions include: a temperature of 50-90° C. and a time of 0.5-5 h.

[0073] In the present invention, preferably, the drying conditions include: a temperature of 100-150° C. and a time of 1-20 h.

[0074] In the present invention, preferably, the calcination conditions include: a temperature of 300-600° C. and a time of 2-10 h.

[0075] In the present invention, before drying the obtained mixed solution, the method further comprises filtering and washing the mixed solution, and then drying and calcining the mixed solution. The present invention has no particular limitation on the filtering and washing methods, and existing filtering and washing methods can be used.

[0076] In the present invention, preferably, in the preparation of the rare earth element modified NSY molecular sieve by the double cross-calcination method, the method further comprises: washing the above molecular sieve with an ammonium sulfate solution (wherein the ammonium sulfate accounts for 10-15 weight % of the dry weight of the molecular sieve) so that the content of sodium oxide in the finally obtained rare earth element modified NSY molecular sieve is less than 2 weight %.

[0077] According to the present invention, preferably, in the NSY molecular sieve, the ratio of the crystallinity measured by the peak height method to the crystallinity measured by the peak area method is 0.76-0.89. According to common knowledge of crystal crystallization, 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 crystallites. The NSY molecular sieve described in the present invention sets a ratio of the crystallinity measured by the peak height method to the crystallinity measured by the peak area method. The size of the ratio indicates the size of the crystallites. A larger ratio indicates a larger crystallite size.

[0078] According to the present invention, preferably, in the NSY molecular sieve, the ratio of the silicon-to-aluminum ratio calculated using the unit cell constant to the silicon-to-aluminum ratio determined by a chemical method is 0.87-0.93. In the present invention, the silicon-to-aluminum ratio calculated using the unit cell constant is calculated using the formula: 2×(25.858-unit cell constant) / (unit cell constant-24.191), wherein the unit cell constant is determined according to the RIPP145-90 standard method.

[0079] According to the present invention, preferably, the macro-porosity of the NSY molecular sieve is 10-20%. In the present invention, the macro-porosity refers to pores with a pore diameter greater than 0.8 nm. The macro-porosity of the present invention is calculated by the formula: (V 总孔 -V 微孔 ) / V 总孔 × 100%, where the total pore volume and micropore volume were determined by nitrogen adsorption method (RIPP151-90).

[0080] According to the present invention, preferably, the NSY molecular sieve refers to an NSY molecular sieve synthesized by in-situ crystallization of kaolin, and the specific preparation method includes:

[0081] (1) calcining kaolin to obtain metakaolin, and then mixing the metakaolin with a sodium silicate solution, a directing agent, and an alkali solution to obtain a mixed slurry;

[0082] (2) The mixed slurry is subjected to a first crystallization and then mixed with solid silica gel, and then subjected to a second crystallization and drying to obtain NSY molecular sieve.

[0083] According to the present invention, preferably, in step (1), the calcination conditions include: a temperature of 500-900° C. and a time of 1-10 h.

[0084] According to the present invention, preferably, the mass ratio of the directing agent to the metakaolin in step (1) is 0.01-1. In the present invention, the molar composition of the directing agent is: 16Na2O:Al2O3:15SiO2:320H2O, and the directing agent can be prepared according to the existing technology.

[0085] The present invention has a wide range of selection for the amount of sodium silicate and alkali solution added in step (1). Preferably, the mass ratio of the sodium silicate solution to the metakaolin is 3-4. Preferably, the mass ratio of the alkali solution to the metakaolin is 1-1.5. The present invention has a wide range of selection for the concentration of the alkali solution in step (1). Preferably, the concentration of the alkali solution is 2-10% by weight. The present invention has a wide range of selection for the alkali solution in step (1). Preferably, the alkali solution is sodium hydroxide solution and / or potassium hydroxide solution.

[0086] In the present invention, in order to fully mix the metakaolin with the sodium silicate solution, the directing agent, and the alkali solution, the metakaolin can be pulverized to obtain a powder with a smaller particle size, which is then mixed with the sodium silicate solution, the directing agent, and the alkali solution. The present invention does not particularly limit the pulverization, and any conventional method in the art can be used.

[0087] According to the present invention, preferably, in step (2), the conditions for the first crystallization include: temperature of 88-98° C., and time of 1-70 h.

[0088] According to the present invention, preferably, the mass ratio of the solid silica gel to the metakaolin in step (2) is 0.01-1.

[0089] According to the present invention, preferably, the conditions for the second crystallization in step (2) include: temperature of 88-98° C. and time of 1-20 h.

[0090] In the present invention, the mixing in step (1), the first crystallization in step (2), the second crystallization, and the mixing in step (2) are all performed under stirring conditions. The present invention does not particularly limit the stirring. Those skilled in the art can select the stirring rate of the stirring device according to actual needs. Preferably, the stirring rate is 300-500 r / min.

[0091] The present invention has no specific limitation on the drying in step (2), which can be a conventional choice in the art. Preferably, the drying conditions in step (2) include: a temperature of 120-150° C. and a time of 6-10 h.

[0092] In the present invention, prior to the drying step (2), the product after the second crystallization is further cooled, filtered, and washed in sequence. The present invention does not particularly limit the methods of cooling, filtering, and washing, and these methods may be conventionally selected in the art. Preferably, the washing conditions are such that the pH value of the washing solution obtained after washing is less than 10.

[0093] The preparation method of the NSY molecular sieve of the present invention can be summarized as follows: first, metakaolin is mixed with a sodium silicate solution and other additives, then a first crystallization is performed and the mixture is mixed with solid silica gel, and then a second crystallization is performed, i.e., two silicon sources (sodium silicate and solid silica gel) are added, and the two silicon sources are added step by step, and a total of two crystallizations are performed simultaneously.

[0094] The present invention offers a wide range of options for the five-membered ring molecular sieve. Preferably, the five-membered ring molecular sieve is selected from at least one of a BEA molecular sieve, an MFI molecular sieve, and a mordenite molecular sieve, more preferably a BEA molecular sieve and / or an MFI molecular sieve. The BEA molecular sieve can be obtained by amine-free crystallization or by calcining a molecular sieve prepared by a template method, such as a β-type molecular sieve. The present invention offers a wide range of options for the MFI molecular sieve. Preferably, the MFI molecular sieve is selected from at least one of a rare earth-containing MFI molecular sieve, a phosphorus-containing MFI molecular sieve, and an iron-containing MFI molecular sieve.

[0095] The present invention has a wide selection range for the mordenite type molecular sieve. Preferably, the mordenite type molecular sieve is a high-silicon mordenite type molecular sieve and / or a low-silicon mordenite type molecular sieve.

[0096] According to the present invention, the aluminum-based binder has a wide selection range. Preferably, the aluminum-based binder is selected from at least one of aluminum sol, acidified aluminum stone and metal-modified aluminum stone (pseudo-boehmite, also known as aluminum stone).

[0097] According to the present invention, the clay can be selected from a wide range. Preferably, the clay is one or more of kaolin, halloysite, montmorillonite, diatomite, halloysite, saponite, rectorite, sepiolite, attapulgite, hydrotalcite and bentonite.

[0098] A third aspect of the present invention provides a method for preparing a catalytic cracking catalyst, comprising: mixing a molecular sieve, the composite material according to the first aspect of the present invention or a zirconium sol and a silica-alumina material forming the composite material, an aluminum-based binder, and clay, and then sequentially drying and calcining the mixture to obtain a catalytic cracking catalyst;

[0099] The molecular sieve, composite material, aluminum-based binder and clay are used in such amounts that, based on the total amount of the catalyst, the molecular sieve content is 10-70% by weight, the composite material content is 6-50% by weight, the aluminum-based binder content is 5-30% by weight, and the clay content is 10-70% by weight;

[0100] The molecular sieve comprises a first molecular sieve and an optional second molecular sieve, wherein the content of the first molecular sieve is 70-100% by weight and the content of the second molecular sieve is 0-30% by weight based on the total amount of the molecular sieve;

[0101] The first molecular sieve is a Y-type molecular sieve, wherein the content of rare earth elements in the Y-type molecular sieve is 0-20% by weight; the second molecular sieve is a molecular sieve with a five-membered ring structure.

[0102] According to the present invention, preferably, the molecular sieve is mixed with the composite material, the aluminum-based binder and the clay in the following manner: clay slurry and molecular sieve slurry are prepared separately, the zirconium sol and the silicon-aluminum material can be mixed to form a composite material, and then mixed with the other components (including clay slurry, molecular sieve slurry and aluminum-based binder), or the zirconium sol and the silicon-aluminum material can be added separately during the mixing, and the other components (including clay slurry, molecular sieve slurry and aluminum-based binder) can be added in the middle of the mixing of the two materials. The mixing of the various materials described in the present invention is carried out under stirring conditions.

[0103] The present invention has no particular limitation on the method for forming the clay slurry. Preferably, clay is mixed with water and then slurried to obtain the clay slurry.

[0104] The present invention does not particularly limit the method for forming the molecular sieve slurry. Preferably, the molecular sieve is mixed with water and then slurried to obtain the molecular sieve slurry. When the molecular sieve includes both a first molecular sieve and a second molecular sieve, the first molecular sieve slurry and the second molecular sieve slurry can be prepared separately, and then the first molecular sieve slurry and the second molecular sieve slurry are mixed and dispersed using a homogenizer to obtain the molecular sieve slurry.

[0105] In the present invention, during the mixing process of various materials, aluminum oxide can be further added thereto.

[0106] It should be noted that when acidified boehmite is further added thereto, the total content of the aluminum-based binder in the prepared catalyst is the sum of the aluminum-based binder content and the acidified boehmite (abbreviation for acidified pseudo-boehmite) content.

[0107] The present invention has no particular limitation on the drying method, which may be a conventional method in the art, and is preferably spray drying.

[0108] According to the present invention, preferably, the calcination conditions include: a temperature of 350-600° C. and a time of 2-6 hours.

[0109] In the present invention, after calcining the mixture and before obtaining the catalytic cracking catalyst, the method further includes washing the calcined product with an ammonium sulfate solution (wherein the ammonium sulfate accounts for 3-10% by weight of the dry weight of the calcined product), and then drying to obtain the catalytic cracking catalyst. The present invention does not particularly limit the number of washings and can be selected conventionally in the art, preferably 1-2 times. The present invention does not particularly limit the drying conditions and can be selected conventionally in the art.

[0110] In the present invention, a catalytic cracking catalyst is prepared using a molecular sieve, a composite material (including zirconium sol and silica-alumina material), an aluminum-based binder, and clay. The zirconium sol particles in the composite material are relatively small, concentrated, have numerous surface hydroxyl groups, and exhibit excellent bonding properties. Introducing the zirconium element in the form of a sol further enhances the catalyst's wear resistance. Furthermore, the combination of zirconium sol and silica-alumina material can further enhance the catalyst's activity, stability, and heavy oil conversion rate. Preferably, when the molecular sieve is a rare earth element (10-20 wt%)-modified NSY molecular sieve, the catalyst's activity can be further enhanced while reducing coke selectivity.

[0111] Therefore, when the catalytic cracking catalyst provided above in the present invention or the catalyst prepared by the preparation method of the catalytic cracking catalyst provided above is used in a catalytic cracking reaction, the strength, heavy oil conversion rate, total liquid yield and metal pollution resistance of the catalyst can be significantly improved, while reducing the coke selectivity.

[0112] The present invention will be described in detail below through examples. In the following examples, unless otherwise specified, all raw materials used can be obtained from commercial channels.

[0113] Zirconium oxychloride octahydrate: purchased from Aldrich, analytical grade, 98.5%;

[0114] Kaolin: solid content 75% by weight, produced by China Kaolin Co., Ltd. (Suzhou);

[0115] REY molecular sieve: Qilu Catalyst Branch, rare earth content is 16% by weight;

[0116] ZSP-3 molecular sieve: Qilu Catalyst Branch, P2O5 content is 3.02 wt%;

[0117] β-type molecular sieve: Qilu Catalyst Branch;

[0118] Aluminum sol: produced by Shandong Aluminum Plant, solid content 25%;

[0119] Acetic acid: Sinopharm Group, analytical grade, 99%;

[0120] Ammonia: Sinopharm Group, analytical grade, 28%;

[0121] Oxalic acid: Sinopharm Group, analytical grade, 99%;

[0122] Zirconium isopropoxide: Sinopharm Group, analytical grade, 99%

[0123] Triethanolamine: Sinopharm Group, analytical grade, 99%;

[0124] Water glass: Qilu Catalyst Branch, SiO2 250g / L;

[0125] Aluminum sulfate: Sinopharm Group, analytical grade, 99%;

[0126] In the NSY molecular sieve, the silicon-aluminum ratio calculated based on the unit cell constant is calculated by the formula: 2×(25.858-unit cell constant) / (unit cell constant-24.191), wherein the unit cell constant is determined according to the RIPP145-90 standard method;

[0127] The medium and large porosity of the NSY molecular sieve is calculated by the formula: (V 总孔 -V 微孔 ) / V 总孔 × 100%, where the total pore volume and micropore volume were determined by nitrogen adsorption method (RIPP151-90);

[0128] The attrition index of the catalyst is measured using the standard methods RIPP28-90 and RIPP29-90 in "Petrochemical Analysis Methods, RIPP Test Method" (edited by Yang Cuiding, Science Press, published in 1990).

[0129] Preparation of zirconium sol

[0130] Preparation Example I-1

[0131] (a) mixing 130 g of deionized water and 125 g of zirconium oxychloride octahydrate with stirring for 10 min to obtain a solution containing zirconium oxychloride, and mixing the solution containing zirconium oxychloride with 93 g of acetic acid with stirring for 30 min to obtain a first mixed solution;

[0132] (b) adding aqueous ammonia to the first mixed solution using a pump at a pump speed (i.e., a feeding speed) of 5 mL / min, so that the pH value of the resulting clear and transparent zirconium sol A1 is 2.5.

[0133] Figure 1 This is the TEM image of the zirconium sol A1 prepared in Preparation Example I-1 of the present invention. Figure 1 It can be seen that the particle size of the obtained zirconium sol is between 5-15 nm, the average particle size is about 10 nm, and the concentration is above 90%.

[0134] Preparation Example I-2

[0135] (a) mixing 130 g of deionized water and 125 g of zirconium oxychloride octahydrate with stirring for 10 min to obtain a solution containing zirconium oxychloride, and mixing the solution containing zirconium oxychloride with 70 g of oxalic acid with stirring for 30 min to obtain a first mixed solution;

[0136] (b) adding aqueous ammonia to the first mixed solution using a pump at a pump speed (i.e., a feeding rate) of 5 mL / min, so that the pH value of the resulting clear and transparent zirconium sol A2 is 2.5.

[0137] Example I-3

[0138] (a) mixing 170 g of deionized water and 176 g of zirconium isopropoxide for 10 min to obtain a solution containing zirconium isopropoxide, and mixing the solution containing zirconium isopropoxide with 70 g of oxalic acid for 30 min to obtain a first mixed solution;

[0139] (b) triethanolamine was added to the first mixed solution by using a pump, with the pump speed (i.e., the addition rate) being controlled at 5 mL / min, so that the pH value of the obtained clear and transparent zirconium sol A3 was 2.5.

[0140] Preparation of silicon-aluminum materials

[0141] Preparation Example II-1

[0142] (i) gradually adding water glass to aluminum sulfate at 20° C. to obtain a mixture containing water glass and aluminum sulfate, wherein the molar ratio of water glass calculated as SiO 2 to aluminum sulfate calculated as Al 2 O 3 is 75:25;

[0143] (ii) adding a sodium hydroxide solution to the mixture containing water glass and aluminum sulfate, wherein the amount of the sodium hydroxide solution added is such that the pH value of the resulting slurry is 10, and then aging the slurry at 50° C. for 6 hours to obtain a solid precipitate;

[0144] (iii) The solid precipitate was dried at 120° C. for 6 h, and then the solid precipitate on a dry basis was mixed with ammonium chloride and water in a weight ratio of 1:0.075:15 at 50° C. for ammonium exchange. The number of exchanges was 2, and the time of each exchange was 1 h. Then, the silicon-aluminum material B1 with a sodium content of 0.2 wt% was obtained by filtration. The expression and physicochemical properties of the silicon-aluminum material B1 are listed in Table 1.

[0145] Preparation Example II-2

[0146] (i) gradually adding water glass to aluminum sulfate at 50° C. to obtain a mixture containing water glass and aluminum sulfate, wherein the molar ratio of water glass calculated as SiO 2 to aluminum sulfate calculated as Al 2 O 3 is 60:30;

[0147] (ii) adding a sodium hydroxide solution to the mixture containing water glass and aluminum sulfate, wherein the amount of the sodium hydroxide solution added is such that the pH value of the resulting slurry is 9.5, and then aging the slurry at 70° C. for 8 hours to obtain a solid precipitate;

[0148] (iii) The solid precipitate was dried at 120° C. for 6 h, and then the solid precipitate on a dry basis was mixed with ammonium chloride and water in a weight ratio of 1:0.05:10 at 40° C. for ammonium exchange. The number of exchanges was 3, and the time of each exchange was 0.5 h. Then, the silicon-aluminum material B2 with a sodium content of 0.1 wt% was obtained by filtration. The expression and physicochemical properties of the silicon-aluminum material B2 are listed in Table 1.

[0149] Comparative Preparation Example II-1

[0150] (1) Using Al2(SO4)3 solution with a concentration of 90gAl2O3 / L and NaAlO2 solution with a concentration of 102gAl2O3 / L and a caustic ratio of 2.5 as the reaction raw materials, the gelling was carried out in a co-current gelling method under vigorous stirring. The system temperature was controlled at 40°C and the system pH value was 9.0. The gelling slurry was collected and measured.

[0151] (2) adding 60 g SiO2 / L water glass to the slurry at a weight ratio of SiO2:Al2O3=1:2 under stirring, heating to 60°C and aging for 3 hours to obtain a first solid precipitate;

[0152] (3) adding NH4Cl and deionized water to the first solid precipitate in a weight ratio of precipitate dry basis: ammonium salt: H2O = 1:0.5:12, and performing ion exchange on the precipitate at 60°C to remove sodium ions. The exchange is repeated once for 0.5 hours each time until the sodium oxide content is less than 0.3%, thereby obtaining a second solid precipitate;

[0153] (4) The obtained second solid precipitate was then mixed with water in a weight ratio of precipitate dry basis: H2O = 1:8, and phosphoric acid and magnesium nitrate were added in a weight ratio of P2O5:MgO: material dry basis = 0.033:0.022:1. The mixture was then reacted at 80°C for 1 hour, filtered, washed with water, and dried at 120°C for 10 hours to obtain a silicon-aluminum material DB1, whose expression and physicochemical properties are listed in Table 1.

[0154] Comparative Preparation Example II-2

[0155] (1) Using an Al2(SO4)3 solution with a concentration of 90 gAl2O3 / L and ammonia water with a concentration of 25 wt% as the reaction raw materials, the Al2(SO4)3 solution and ammonia water were mixed into a gel under vigorous stirring using a co-current gelling method. The system temperature was controlled at 40°C and the system pH value was 9.5. The gel slurry was collected and measured.

[0156] (2) adding 102 g SiO2 / L of water glass to the slurry at a weight ratio of SiO2:Al2O3=1:2.6 under stirring conditions, heating to 70°C and aging for 2 hours to obtain a first solid precipitate;

[0157] (3) subjecting the first solid precipitate to ion exchange at 60° C. in a weight ratio of dry precipitate: ammonium salt: H 2 O = 1:0.8:15 to remove sodium ions, and washing the sodium oxide to 0.3% to obtain a second solid precipitate;

[0158] (4) The precipitate (filter cake) of the second solid precipitate was re-slurried with water, and then mixed with phosphoric acid in a weight ratio of P2O5: dry basis of the precipitate of the second solid precipitate = 0.05:1, heated to 60°C and stirred for 1 hour, filtered, and dried at 120°C for 10 hours to obtain a silicon-aluminum material DB2, the expression and physicochemical properties of which are listed in Table 1.

[0159] Table 1

[0160]

[0161] It can be seen from the results in Table 1 that the expressions of the silicon-aluminum materials prepared by the preparation method provided by the present invention all satisfy (0-1)Na2O·(15-50)Al2O3·(85-50)SiO2 in terms of the weight ratio of the oxides, and the performance of the silicon-aluminum materials is better; while the expressions of the silicon-aluminum materials prepared by the preparation method provided by the comparative example are not within the scope specified in this application, and the performance of the silicon-aluminum materials is poor.

[0162] Preparation of NSY molecular sieve

[0163] Preparation of the directing agent: Take 250 grams of sodium silicate solution (containing 20.05 weight percent SiO2 and 6.41 weight percent Na2O), slowly add 120 grams of sodium aluminate solution (containing 3.15 weight percent Al2O3 and 21.1 weight percent Na2O) under rapid stirring at 30°C, then stir for 1 hour and age at 20°C for 48 hours to obtain a directing agent with a chemical molar composition of 16Na2O:Al2O3:15SiO2:320H2O.

[0164] Preparation Example III-1

[0165] (1) calcining kaolin at 700° C. for 6 h to obtain metakaolin, then crushing the metakaolin to obtain metakaolin powder, taking 100 kg of the crushed metakaolin powder, adding 400 kg of sodium silicate solution (containing 20.05 wt % SiO2 and 6.41 wt % Na2O), 60 kg of a directing agent, and 100 kg of a 5 wt % sodium hydroxide solution under stirring to obtain a mixed slurry;

[0166] (2) The mixed slurry was subjected to a first crystallization at 95°C and a stirring speed of 400 r / min for 8 hours, and then 10 kg of solid silica gel was added and a second crystallization was carried out for 12 hours. After the crystallization was completed, the obtained product was cooled, filtered and washed (washed with water until the pH value of the washing liquid was less than 10), and then dried at 120°C for 6 hours to obtain NSY molecular sieve Y1, whose physicochemical properties are listed in Table 2.

[0167] Preparation Example III-2

[0168] (1) calcining kaolin at 600° C. for 8 h to obtain metakaolin, then crushing the metakaolin to obtain metakaolin powder, taking 100 kg of the crushed metakaolin powder, adding 380 kg of sodium silicate solution (containing 20.05 wt % SiO2 and 6.41 wt % Na2O), 60 kg of a directing agent, and 100 kg of a 5 wt % sodium hydroxide solution under stirring to obtain a mixed slurry;

[0169] (2) The mixed slurry was subjected to a first crystallization at 93°C and a stirring speed of 400 r / min for 8 hours, and then 15 kg of solid silica gel was added and a second crystallization was carried out for 14 hours. After the crystallization was completed, the obtained product was cooled, filtered and washed (washed with water until the pH value of the washing liquid was less than 10), and then dried at 120°C for 6 hours to obtain NSY molecular sieve Y2, whose physicochemical properties are listed in Table 2.

[0170] Preparation Example III-3

[0171] (1) calcining kaolin at 800° C. for 4 h to obtain metakaolin, then crushing the metakaolin to obtain metakaolin powder, taking 100 kg of the crushed metakaolin powder, adding 360 kg of sodium silicate solution (containing 20.05 wt % SiO2 and 6.41 wt % Na2O), 60 kg of a directing agent, and 100 kg of a 5 wt % sodium hydroxide solution under stirring to obtain a mixed slurry;

[0172] (2) The mixed slurry was subjected to a first crystallization at 95°C and a stirring speed of 400 r / min for 8 hours, and then 20 kg of solid silica gel was added and a second crystallization was carried out for 16 hours. After the crystallization, the obtained product was cooled, filtered and washed (washed with water until the pH value of the washing liquid was less than 10), and then dried at 120°C for 6 hours to obtain NSY molecular sieve Y3, whose physicochemical properties are listed in Table 2.

[0173] Comparative Preparation Example III-1

[0174] calcining kaolin at 700° C. for 6 hours to obtain metakaolin, then crushing the metakaolin to obtain metakaolin powder, adding 400 kg of sodium silicate solution (containing 20.05 wt % SiO2 and 6.41 wt % Na2O), 60 kg of a directing agent, 100 kg of a 5 wt % sodium hydroxide solution, and 10 kg of solid silica gel to 100 kg of the crushed metakaolin powder under stirring to obtain a mixed slurry;

[0175] The mixed slurry was crystallized at 95°C with a stirring speed of 400 r / min for 24 hours. After the crystallization, the obtained product was cooled, filtered and washed (washed with water until the pH value of the washing liquid was less than 10), and then dried at 120°C for 6 hours to obtain NSY molecular sieve DY1, whose physicochemical properties are listed in Table 2.

[0176] Comparative Preparation Example III-2

[0177] calcining kaolin at 700° C. for 6 hours to obtain metakaolin, then crushing the metakaolin to obtain metakaolin powder, adding 400 kg of sodium silicate solution (containing 20.05 wt % SiO2 and 6.41 wt % Na2O), 60 kg of a directing agent, and 105 kg of a 5 wt % sodium hydroxide solution to 100 kg of the crushed metakaolin powder under stirring to obtain a mixed slurry;

[0178] The mixed slurry was crystallized at 95°C with stirring at a speed of 400 r / min for 24 hours. After the crystallization, the obtained product was cooled, filtered and washed (washed with water until the pH value of the washing liquid was less than 10), and then dried at 120°C for 6 hours to obtain NSY molecular sieve DY2, whose physicochemical properties are listed in Table 2.

[0179] Table 2

[0180]

[0181] Note: The framework silicon-aluminum ratio refers to the silicon-aluminum ratio calculated based on the unit cell constant. The specific calculation formula is 2×(25.858-unit cell constant) / (unit cell constant-24.191);

[0182] K1 represents the ratio of the crystallinity determined by the peak height method to the crystallinity determined by the peak area method;

[0183] K2 represents the ratio of the silicon-to-aluminum ratio calculated using the unit cell constant to the silicon-to-aluminum ratio determined by chemical methods.

[0184] It can be seen from the results in Table 2 that compared with the NSY molecular sieve prepared by the preparation method provided by the present invention, the NSY molecular sieve prepared in Comparative Preparation Example III-1 by adding sodium silicate and solid silica gel at one time and performing only one crystallization has a lower crystallinity and contains impurity crystals, which affects the performance of the NSY molecular sieve; the NSY molecular sieve prepared in Comparative Preparation Example III-2 by not adding solid silica gel and performing only one crystallization has a good crystallinity, but the silicon-aluminum ratio is low, which affects the performance of the NSY molecular sieve.

[0185] Preparation of rare earth element modified NSY molecular sieve

[0186] The NSY molecular sieves Y1-Y3 prepared in the above preparation example were mixed and slurried with deionized water to obtain molecular sieve slurry; lanthanum chloride was mixed and slurried with deionized water to obtain a lanthanum chloride solution; the lanthanum chloride solution was then added to the above molecular sieve slurry, stirred at 70°C for 1 hour, filtered, washed, and then dried at 150°C for 8 hours and calcined at 500°C for 4 hours; the above steps were repeated to obtain a lanthanum content in the lanthanum-modified NSY molecular sieve as shown in Table 3, and then the molecular sieve was washed with ammonium sulfate solution (wherein ammonium sulfate accounts for 10 weight% of the dry basis weight of the molecular sieve) so that the sodium oxide content in the final lanthanum-modified NSY molecular sieve is less than 2 weight%.

[0187] Table 3

[0188] Product Number Content of lanthanum in NSY molecular sieve (weight %) Y1-1* 12 Y1-2* 10 Y2* 15 Y3* 18

[0189] Note: “*” indicates NSY molecular sieve modified with rare earth elements.

[0190] Example 1

[0191] The catalyst formulations are listed in Table 4.

[0192] First, kaolin is mixed with deionized water and beaten to obtain a kaolin slurry with a solid content of 20% by weight; molecular sieve is mixed with deionized water and beaten to obtain a molecular sieve slurry with a solid content of 35% by weight; a silicon aluminum material is mixed with zirconium sol to obtain a composite material; pseudo-boehmite is mixed with deionized water and beaten, and hydrochloric acid is added for acidification (the molar ratio of hydrochloric acid to pseudo-boehmite calculated as Al2O3 is 0.2) to obtain an acidified boehmite slurry with a solid content of 10% by weight; then the kaolin slurry and molecular sieve slurry are mixed and stirred, and then the composite material and the acidified boehmite slurry are added and stirred for 10 minutes, and then an aluminum-based binder is added to the above mixed slurry and stirred for 30 minutes. Finally, the obtained mixed slurry is spray-dried and calcined at 500°C for 2 hours. The calcined product is washed once with an ammonium sulfate solution (wherein the ammonium sulfate accounts for 5% by weight of the dry basis weight of the calcined product), and then dried to obtain a catalytic cracking catalyst C1.

[0193] The catalyst formulations of other examples and comparative examples are listed in Table 4.

[0194] Table 4

[0195]

[0196]

[0197] Table 4 (Continued)

[0198]

[0199] Table 4 (Continued)

[0200]

[0201] Note: “-” means that the component is not contained.

[0202] Test Example 1

[0203] This test example is used to evaluate the catalytic cracking performance of the catalytic cracking catalysts prepared in the above examples and comparative examples:

[0204] Before the catalytic cracking reaction, the catalytic cracking catalysts prepared in the above examples and comparative examples were subjected to an aging deactivation treatment at 800° C. with 100% water vapor for 15 hours, and then the catalytic cracking reaction was carried out.

[0205] The catalytic cracking catalysts prepared in the above examples and comparative examples were evaluated in a fixed fluidized bed microreactor using hydrotreated reformed oil as feedstock. The composition and physicochemical properties of the hydrotreated reformed oil are listed in Table 5. The reaction temperature was 500°C, and the catalyst-to-oil ratio (by weight) was 6. The evaluation results are listed in Table 6.

[0206] Table 5

[0207] project Hydrogenated modified oil <![CDATA[Density (20 °C), g / cm 3 > 0.9334 Refractive index (70℃) 1.5061 Four components, m% saturated hydrocarbons 55.6 Aromatics 30 colloid 14.4 Asphaltene ＜0.1 Freezing point, ℃ 34 Metal content, ppm Ca 3.9 Fe 1.1 Mg ＜0.1 Na 0.9 Ni 3.1 Pb ＜0.1 V 0.5 C, m% 86.88 H, m% 11.94 S, m% 0.7 Carbon residue, m% 1.77 H, m% 11.94

[0208] Table 6

[0209]

[0210] Table 6 (Continued)

[0211]

[0212] Note: Conversion rate = gasoline yield + liquefied gas yield + dry gas yield + coke yield;

[0213] Total liquid yield = liquefied gas yield + C5 + Gasoline yield + cycle oil yield;

[0214] Coke factor = coke yield × (1 - conversion rate) / conversion rate × 100.

[0215] From the results in Table 6, it can be seen that compared with the catalysts provided by the prior art, the catalytic cracking catalyst provided by the present invention has better micro-reaction activity and higher strength. When the catalyst is used in a catalytic cracking reaction, the conversion rate and total liquid yield can be further improved, and the coke selectivity and coke factor can be reduced.

[0216] Test Example 2

[0217] Catalysts C1-C6 and DC1-DC3 prepared in the above Examples and Preparation Examples were impregnated with metal contaminants of 1000 μg / g nickel and 3000 μg / g vanadium using the Michael method. The contaminated catalysts were aged at 780°C with 100% steam for 4 hours and then subjected to catalytic cracking reactions under the same conditions as described above. The results are listed in Table 7.

[0218] Table 7

[0219]

[0220]

[0221] Table 7 (Continued)

[0222]

[0223] Note: Conversion rate = gasoline yield + liquefied gas yield + dry gas yield + coke yield.

[0224] From the results in Table 7, it can be seen that compared with the catalysts provided by the prior art, the catalytic cracking catalyst provided by the present invention still has high micro-reaction activity and conversion rate after being contaminated by metals, indicating that the catalytic cracking catalyst provided by the present invention has strong resistance to metal contamination.

[0225] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A composite material, characterized in that The composite material comprises zirconium sol and silicon-aluminum material. Based on the total amount of the composite material, the content of zirconium sol is 30-80% by weight and the content of silicon-aluminum material is 20-70% by weight on a dry basis. The particle size of the zirconium sol is between 5-15 nm, the average particle size is 8-12 nm, and the concentration is above 90%. The average pore size of the silicon-aluminum material is 10-100 nm, and the specific surface area is 150-600 m 2 / g, pore volume of 0.5-1.5cm 3 / g; The expression of the silicon-aluminum material is (0.2-1)Na2O·(25-50)Al2O3·(74.8-50)SiO2 in terms of the weight ratio of the oxides; The preparation method of the silicon-aluminum material comprises: (i) mixing a silicon source with an aluminum source to obtain a mixture containing the silicon source and the aluminum source; (ii) adding an alkaline solution to the mixture containing the silicon source and the aluminum source to obtain a slurry, and then aging the slurry to obtain a solid precipitate; (iii) contacting the solid precipitate with an ammonium salt or an acid to obtain a silica-alumina material.

2. The composite material according to claim 1, wherein The preparation method of the zirconium sol comprises: (a) mixing a solution containing a zirconium source with an acid to obtain a first mixed solution; (b) adding an alkaline solution to the first mixed solution to obtain a zirconium sol.

3. The composite material according to claim 2, wherein In step (a), the concentration of the solution containing the zirconium source is 0.5-20 wt % calculated as ZrO 2 .

4. The composite material according to claim 2, wherein In step (a), the molar ratio of the solution containing the zirconium source to the acid, calculated as Zr element, is 1:1-6.

5. The composite material according to claim 2, wherein The mixing conditions in step (a) include: temperature of 20-90° C. and time of 0.5-3 h.

6. The composite material according to claim 2, wherein The acid in step (a) is an organic acid.

7. The composite material according to claim 6, wherein The acid in step (a) is at least one of glycolic acid, acetic acid, oxalic acid, malonic acid, malic acid, tartaric acid, succinic acid, adipic acid, maleic acid, itaconic acid and citric acid.

8. The composite material according to claim 7, wherein The acid in step (a) is acetic acid and / or citric acid.

9. The composite material according to claim 2, wherein The zirconium source in step (a) is an inorganic zirconium salt and / or an organic zirconium salt.

10. The composite material according to claim 9, wherein The inorganic zirconium salt is selected from at least one of zirconium tetrachloride, zirconium oxychloride, zirconium acetate, zirconium nitrate, zirconyl nitrate, zirconyl sulfate and zirconyl carbonate.

11. The composite material according to claim 9, wherein The organic zirconium salt is selected from at least one of zirconium n-propoxide, zirconium isopropoxide, zirconium ethoxide and zirconium butoxide.

12. The composite material according to claim 2, wherein The amount of alkali solution added in step (b) is such that the pH value of the zirconium sol is 1-7.

13. The composite material according to claim 12, wherein The amount of alkali solution added in step (b) is such that the pH value of the zirconium sol is 1.5-5.

14. The composite material according to claim 13, wherein The amount of alkali solution added in step (b) is such that the pH value of the zirconium sol is 2-3.

15. The composite material according to claim 2, wherein The alkali solution in step (b) is aqueous ammonia and / or a water-soluble organic base.

16. The composite material according to claim 15, wherein The water-soluble organic base is selected from at least one of methylamine, dimethylamine, trimethylamine, methanolamine, dimethanolamine, trimethanolamine, triethylamine, ethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, monomethyltriethylammonium hydroxide, monomethyltriethanolammonium hydroxide and monomethyltributylammonium hydroxide.

17. The composite material according to claim 1 or 2, wherein: In step (i), the molar ratio of the silicon source calculated as SiO2 to the aluminum source calculated as Al2O3 is 50-85:50-15.

18. The composite material according to claim 1 or 2, wherein The mixing conditions in step (i) include: a temperature of 20-95°C.

19. The composite material according to claim 1 or 2, wherein: The silicon source in step (i) is an alkaline silicon source.

20. The composite material according to claim 19, wherein The silicon source in step (i) is one or more of alkaline silica sol, water glass, sodium silicate, and alkaline hydrolysis products of metal alkoxides of silicon.

21. The composite material according to claim 1 or 2, wherein The aluminum source in step (i) is an acidic aluminum source.

22. The composite material according to claim 21, wherein The aluminum source in step (i) is one or more of aluminum sulfate, aluminum chloride, aluminum sol, and an acidic hydrolysis product of aluminum metal alkoxide.

23. The composite material according to claim 1 or 2, wherein The amount of alkali solution added in step (ii) is such that the pH value of the slurry is 8-10.

5.

24. The composite material according to claim 1 or 2, wherein the aging conditions in step (ii) include: The temperature is 50-95℃ and the time is 1-10h. 25 . The composite material according to claim 1 , wherein the alkaline solution in step (ii) is at least one selected from the group consisting of aqueous ammonia, sodium hydroxide solution, potassium hydroxide solution, and sodium metaaluminate solution.

26. The composite material according to claim 1 or 2, wherein In step (iii), the solid precipitate is contacted with the ammonium salt by mixing the solid precipitate with the ammonium salt and water to perform ammonium exchange.

27. The composite material according to claim 26, wherein In step (iii), the weight ratio of the solid precipitate to the ammonium salt and water on a dry basis is 1:0.05-0.1:5-30.

28. The composite material according to claim 26, wherein In step (iii), the ammonium exchange is carried out under conditions such that the sodium content of the silica-alumina material is less than 1 wt %.

29. The composite material according to claim 28, wherein In step (iii), the conditions for the ammonium exchange include: a temperature of 20-100° C., 1-3 exchanges, and a time of 0.5-1 h for each exchange.

30. The composite material according to claim 26, wherein In step (iii), the ammonium salt is selected from at least one of ammonium chloride, ammonium sulfate, ammonium nitrate, ammonium carbonate and ammonium bicarbonate.

31. The composite material according to claim 1 or 2, wherein In step (iii), the solid precipitate is contacted with the acid by mixing the solid precipitate with the acid and water for acid treatment.

32. The composite material according to claim 31, wherein In step (iii), the weight ratio of the solid precipitate to the acid and water on a dry basis is 1:0.03-0.3:5-30.

33. The composite material according to claim 31, wherein In step (iii), the acid treatment is performed under conditions such that the sodium content of the silicon-aluminum material is less than 1 wt %.

34. The composite material according to claim 33, wherein In step (iii), the acid treatment conditions include: temperature of 20-100° C. and time of at least 0.5 h.

35. The composite material according to claim 34, wherein In step (iii), the acid treatment conditions include: time is 1-3 hours.

36. The composite material according to claim 31, wherein In step (iii), the acid is selected from at least one of sulfuric acid, hydrochloric acid and nitric acid.

37. A catalytic cracking catalyst, characterized in that The catalyst comprises a molecular sieve, an aluminum-based binder, clay, and the composite material according to any one of claims 1 to 36, wherein, based on the total amount of the catalyst, the content of the molecular sieve is 10-70% by weight, the content of the aluminum-based binder is 5-30% by weight, the content of the clay is 10-70% by weight, and the content of the composite material is 6-50% by weight; The molecular sieve comprises a first molecular sieve and an optional second molecular sieve, wherein the content of the first molecular sieve is 70-100 wt % and the content of the second molecular sieve is 0-30 wt % based on the total amount of the molecular sieve; The first molecular sieve is a Y-type molecular sieve, wherein the content of rare earth elements in the Y-type molecular sieve is 0-20% by weight; the second molecular sieve is a molecular sieve with a five-membered ring structure.

38. The catalyst according to claim 37, wherein The Y-type molecular sieve is at least one of HY molecular sieve, REY molecular sieve, NSY molecular sieve, REHY molecular sieve, USY molecular sieve, REUSY molecular sieve, DASY molecular sieve and REDASY molecular sieve.

39. The catalyst according to claim 37 or 38, wherein The first molecular sieve is a REY molecular sieve and / or a rare earth element modified NSY molecular sieve.

40. The catalyst according to claim 39, wherein The content of the rare earth element in the NSY molecular sieve is 10-20% by weight.

41. The catalyst according to claim 39, wherein The rare earth element is selected from at least one of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

42. The catalyst according to claim 41, wherein The rare earth element is La.

43. The catalyst according to claim 38, wherein In the NSY molecular sieve, the ratio of the crystallinity determined by the peak height method to the crystallinity determined by the peak area method is 0.76-0.

89.

44. The catalyst according to claim 38, wherein In the NSY molecular sieve, the ratio of the silicon-to-aluminum ratio calculated using the unit cell constant to the silicon-to-aluminum ratio determined by a chemical method is 0.87-0.

93.

45. The catalyst according to claim 38, wherein The medium and macropore rate of the NSY molecular sieve is 10-20%.

46. ​​The catalyst according to claim 38, wherein The preparation method of the NSY molecular sieve comprises: (1) calcining kaolin to obtain metakaolin, and then mixing the metakaolin with a sodium silicate solution, a directing agent, and an alkali solution to obtain a mixed slurry; (2) The mixed slurry is subjected to a first crystallization and then mixed with solid silica gel, and then subjected to a second crystallization and drying to obtain NSY molecular sieve.

47. The catalyst according to claim 46, wherein In step (1), the calcination conditions include: temperature of 500-900°C and time of 1-10h.

48. The catalyst according to claim 46 or 47, wherein The mass ratio of the directing agent to the metakaolin in step (1) is 0.01-1.

49. The catalyst according to claim 46 or 47, wherein In step (2), the conditions for the first crystallization include: temperature of 88-98° C. and time of 1-70 h.

50. The catalyst according to claim 46 or 47, wherein The mass ratio of the solid silica gel to the metakaolin in step (2) is 0.01-1.

51. The catalyst according to claim 46 or 47, wherein Step (2) The conditions for the second crystallization include: temperature of 88-98° C. and time of 1-20 h.

52. The catalyst according to claim 37 or 38, wherein The molecular sieve having a five-membered ring structure is at least one selected from BEA molecular sieve, MFI molecular sieve and mordenite molecular sieve.

53. The catalyst according to claim 52, wherein The molecular sieve having a five-membered ring structure is a BEA type molecular sieve and / or an MFI type molecular sieve.

54. The catalyst according to claim 52, wherein The MFI type molecular sieve is at least one selected from a rare earth-containing MFI type molecular sieve, a phosphorus-containing MFI type molecular sieve, and an iron-containing MFI type molecular sieve.

55. The catalyst according to claim 52, wherein The mordenite molecular sieve is a high-silicon mordenite molecular sieve and / or a low-silicon mordenite molecular sieve.

56. The catalyst according to claim 37 or 38, wherein The aluminum-based binder is selected from at least one of aluminum sol, acidified aluminum stone and metal-modified aluminum stone.

57. The catalyst according to claim 37 or 38, wherein The clay is one or more of kaolin, montmorillonite, diatomite, halloysite, saponite, rectorite, sepiolite, attapulgite, hydrotalcite and bentonite.

58. A method for preparing a catalytic cracking catalyst, characterized in that: The method comprises: mixing a molecular sieve, the composite material according to any one of claims 1 to 36, an aluminum-based binder and clay, and then sequentially drying and calcining to obtain a catalytic cracking catalyst; The molecular sieve, composite material, aluminum-based binder and clay are used in such amounts that, based on the total amount of the catalyst, the molecular sieve content is 10-70% by weight, the composite material content is 6-50% by weight, the aluminum-based binder content is 5-30% by weight, and the clay content is 10-70% by weight; The molecular sieve comprises a first molecular sieve and an optional second molecular sieve, wherein the content of the first molecular sieve is 70-100 wt % and the content of the second molecular sieve is 0-30 wt % based on the total amount of the molecular sieve; The first molecular sieve is a Y-type molecular sieve, wherein the content of rare earth elements in the Y-type molecular sieve is 0-20% by weight; the second molecular sieve is a molecular sieve with a five-membered ring structure.

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