Macroporous catalytic cracking catalyst, preparation method therefor, and use thereof

Abstract

The present invention relates to a catalytic cracking catalyst, comprising: 5-40 wt% of a molecular sieve, 5-40 wt% of clay calculated on a dry basis, 5-35 wt% of a silicon species calculated on the basis of SiO2, 30-75 wt% of an aluminum species calculated on the basis of Al2O3, 0.5-15 wt% of a stabilizing element calculated on the basis of an oxide, and 0.5-10 wt% of an activity-modifying element calculated on the basis of an oxide. The content ratio of the silicon species to the aluminum species is 0.05-2 calculated on the basis of the molar ratio of SiO2 / Al2O3. The stabilizing element is selected from at least one of group IIIB elements and group IVB elements, and the activity-modifying element is selected from at least one of Mg and P; or the stabilizing element is selected from Mg, and the activity-modifying element is selected from at least one of P, B, Fe, group IIIB elements, and group IVB elements. The present invention further relates to a method for preparing the catalytic cracking catalyst and a heavy oil catalytic cracking method.

Description

Macroporous catalytic cracking catalysts, their preparation methods and applications Technical Field

[0001] This invention relates to the field of refining catalysts, and more specifically to a highly active macroporous catalytic cracking catalyst, its preparation method, and its use in the catalytic cracking reaction of heavy oil to reduce the coke yield of the catalytic cracking reaction. Background Technology

[0002] The oil refining industry is facing severe challenges such as petroleum resource shortages, degradation of quality, and the need for low-carbon emissions. Catalytic cracking, as an important secondary processing step, can efficiently convert heavy oil and residue into high-value products such as liquefied petroleum gas (LPG), gasoline, and diesel. However, with the increasing trend of heavier and lower-quality feedstocks, heavy feedstocks are characterized by large molecular size, high density, high carbon residue, and high heavy metal content, placing stringent demands on catalytic cracking catalysts. To meet these requirements, the pore structure of the catalyst needs to be optimized to improve the diffusion rate of heavy feedstocks and prevent the condensation and coking of large molecules such as polycyclic aromatic hydrocarbons in the feedstock. Simultaneously, the activity and stability of the catalyst also need to be improved to meet the requirements of deep catalytic cracking of heavy oil. Therefore, the development of macroporous catalytic cracking catalysts with high activity and stability is of great significance.

[0003] CN105688977A discloses a method for preparing a catalytic cracking catalyst containing boehmite. The method includes mixing a portion of boehmite with a silicon-containing solution and stirring for at least 15 minutes to prepare modified boehmite A; mixing modified boehmite A, the remaining boehmite B, and clay to prepare a matrix slurry containing boehmite; mixing the matrix slurry and a molecular sieve slurry, homogenizing, shaping, drying, and ion-exchanging to obtain the catalytic cracking catalyst. The catalyst prepared by this method has a high macropore volume, with macropore diameters mainly distributed above 100 nm, lacking mesopore structures of 5-100 nm.

[0004] CN108786901A discloses a heavy metal-resistant catalytic cracking catalyst and its preparation method. This heavy metal-resistant catalytic cracking catalyst, based on a catalyst mass composition of 100 parts, comprises 80-50 parts matrix, including 1-20 parts rare earth-containing mesoporous and macroporous silica-alumina material; 0.5-15 parts large-grain alumina material; and 20-50 parts molecular sieve. This catalytic cracking catalyst exhibits strong resistance to heavy metals, low slurry oil yield, and high total liquid product yield. However, the method introduces a limited amount of mesoporous and macroporous silica-alumina material, resulting in a catalyst pore volume not exceeding 0.5 mL / g. Furthermore, this catalyst still suffers from insufficient distribution of mesoporous and macroporous pores.

[0005] CN117696043A discloses a highly active solid base catalyst, its preparation method, and its application. The catalyst contains 0.1 wt%-20 wt% of active metal oxide and 0.1 wt%-10 wt% of auxiliary metal oxide, with the balance being a highly active mesoporous support. Based on the total weight of the highly active mesoporous support, the support contains 1 wt%-80 wt% of modified mesoporous material, 1 wt%-50 wt% of alumina material, and the balance being clay. The catalyst forming process avoids the introduction of traditional binders with poor hydrothermal stability and small specific surface area. The catalyst achieves a specific surface area of ​​226 m² after hydrothermal treatment at 800℃ for 17 hours. 2 / g, with a mesoporous pore volume of 0.42cm³. 3 / g, but the catalyst still has the problem of insufficient distribution of mesopores and macropores.

[0006] CN118320851A discloses a catalytic cracking catalyst composition with a medium-to-large pore size structure and its preparation method. The catalyst composition comprises the following components: 10-40 wt% (based on oxides) of a macroporous silica-boehmite composition, 5-40 wt% of a binder, 20-50 wt% of a molecular sieve, and 15-50 wt% (based on dry basis) of clay; the macroporous silica-boehmite composition has a pore volume of 0.8-1.3 mg / L and a specific surface area of ​​220-280 m². 2 The catalyst has a pore diameter of 16-30 nm per g, with mesopores (10-60 nm) accounting for more than 60% of the total pore volume. This catalyst exhibits good abrasion resistance and a rich mesopore-macropore structure, enhancing heavy oil conversion and reducing coke yield. However, it suffers from high manufacturing costs and its catalytic performance stability is not yet entirely satisfactory. Summary of the Invention

[0007] The purpose of this invention is to overcome the problem of simultaneously achieving large porosity, high catalytic activity, and high stability in existing catalytic cracking catalysts, and to provide a highly active macroporous catalytic cracking catalyst. This catalyst exhibits advantages such as high heavy oil conversion rate, high light oil selectivity, and low coke yield. Furthermore, the invention also aims to provide a method for preparing the aforementioned highly active macroporous catalytic cracking catalyst, and a method for heavy oil catalytic cracking using the aforementioned macroporous catalytic cracking catalyst.

[0008] To achieve the above objectives, the inventors have surprisingly discovered through research that when the catalytic cracking catalyst contains a silicon-aluminum matrix with a Si / Al molar ratio of less than or equal to 1, specific stabilizing elements, and specific activity-regulating elements, the above problems can be solved. That is, the catalytic cracking catalyst can simultaneously possess high activity stability, high pore volume, and suitable pore size distribution.

[0009] In this specification, the term "matrix" refers to the substances contained in the catalyst other than molecular sieves, active elements, stabilizing elements and clay, and the term "silicon-aluminum matrix" refers to a silicon and aluminum matrix that is mainly generated from silicon-source compounds and aluminum-source compounds used in the preparation of the catalytic cracking aid.

[0010] Furthermore, the inventors have surprisingly discovered that, in the method for preparing the above-mentioned catalytic cracking catalyst, by incorporating or loading the specific stabilizing element and the specific activity regulating element in different preparation steps, so that the stabilizing element and the activity regulating element are distributed in a specific form in different regions of the catalyst microspheres, the macroporosity, catalytic activity and stability of the above-mentioned catalytic cracking catalyst can be further improved.

[0011] Therefore, according to a first aspect of the present invention, the present invention provides a catalytic cracking catalyst, wherein, based on the total dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 5-40 wt% molecular sieve, 5-40 wt% clay on a dry basis, 5-35 wt% silicon species on a SiO2 basis, 30-75 wt% aluminum species on an Al2O3 basis, 0.5-15 wt%, preferably 0.5-5 wt% stabilizing element on an oxide basis, and 0.5-10 wt% activity regulating element on an oxide basis; the content ratio of the silicon species and aluminum species on a SiO2 / Al2O3 molar ratio is 0.05-2; wherein the stabilizing element is selected from at least one of Group IIIB and Group IVB elements, and the activity regulating element is selected from at least one of Mg and P; or, the stabilizing element is selected from Mg, and the activity regulating element is selected from at least one of P, B, Fe, Group IIIB and Group IVB elements.

[0012] The catalytic cracking catalyst according to the present invention has a high macropore volume and a suitable pore size distribution; wherein, as determined by low-temperature nitrogen adsorption, the total pore volume of the catalytic cracking catalyst is not less than 0.5 mL / g, and wherein the pore volume of pores with a diameter of 10-100 nm accounts for more than 80% of the total pore volume, preferably 85%-99%. Furthermore, the catalytic cracking catalyst according to the present invention has high catalytic activity and improved stability, wherein the microreaction activity of the catalytic cracking catalyst after hydrothermal treatment, especially after treatment at 800°C and 100% steam for 17 hours, is not less than 50, preferably not less than 60.

[0013] In this specification, the term "silicon species" refers to silicon-containing substances or silicon elements other than clay and molecular sieves contained in the catalytic cracking catalyst; the term "aluminum species" refers to aluminum-containing substances or aluminum elements other than clay and molecular sieves contained in the catalytic cracking catalyst. The term "oxide" in the description of "stabilizing element based on oxides" refers to the oxide of the stabilizing element source formed after calcination, and the term "oxide" in the description of "activity regulating element based on oxides" refers to the oxide of the stabilizing element source formed after calcination, such as MgO, La2O3, CeO2, Y2O3, P2O5, ZrO2, etc.

[0014] According to a second aspect of the present invention, the present invention provides a method for preparing a catalytic cracking catalyst, particularly the catalytic cracking catalyst of the first aspect described above, characterized in that the method comprises the following steps:

[0015] (1) A mixed gel is prepared by uniformly mixing a silicon source, an aluminum source, a stabilizing element source, and an optional acid in the presence of a solvent.

[0016] (2) The obtained mixed gel is subjected to aging treatment to obtain a stabilized mixed gel;

[0017] (3) The stabilized mixed gel is mixed with clay and molecular sieve to obtain a slurry, which is then spray-dried and optionally calcined to obtain catalyst microspheres.

[0018] (4) Allow the catalyst microspheres to undergo ammonium ion exchange, and

[0019] (5) Loading an activity-regulating element onto ammonium ion-exchanged catalyst microspheres; optionally filtering, drying, and calcining the catalyst microspheres loaded with the activity-regulating element; to obtain a catalytic cracking catalyst;

[0020] The amount of the stabilizing element source, silicon source, aluminum source, clay, molecular sieve, and activity regulating element source added is such that, based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 5-40 wt% molecular sieve, 5-40 wt% clay on a dry basis, 5-35 wt% silicon species based on SiO2, 30-75 wt% aluminum species based on Al2O3, 0.5-15 wt%, preferably 0.5-5 wt% stabilizing element based on oxide, and 0.5-10 wt% activity regulating element based on oxide; the content ratio of silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.05-2.

[0021] In the preparation method according to the present invention, a catalytic cracking catalyst with high catalytic activity is obtained by having catalyst microspheres produced by spray drying a stabilized mixed gel with a large total pore volume and a wide pore distribution, and by loading activity-regulating elements on the surface of the catalyst microspheres and possibly in the channels of a very thin microsphere surface layer (thickness, for example, less than 1 micrometer). The present invention obtains a catalytic cracking catalyst comprising a matrix with a specific Si / Al molar ratio and containing a combination of specific stabilizing elements and specific activity-regulating elements. This catalytic cracking catalyst exhibits abundant macroporous structure and excellent catalytic activity and stability, resulting in enhanced heavy oil conversion, high light oil yield, and low coke yield when used for the catalytic cracking of heavy oil. The above-mentioned properties of the catalytic cracking catalyst are further improved when the combination of the stabilizing elements and the activity-regulating elements is distributed in a specific distribution within the catalyst microsphere particles.

[0022] According to a third aspect of the present invention, a method for catalytic cracking of heavy oil is provided, in which a catalytic cracking catalyst according to the first aspect of the present invention, or a catalytic cracking catalyst prepared by the method according to the second aspect of the present invention, is contacted with heavy oil to undergo a catalytic cracking reaction. The catalytic cracking catalyst allows for increased light oil yield and reduced coke yield.

[0023] Through the above three technical solutions, the present invention has the following beneficial effects:

[0024] Because the catalytic cracking catalyst according to the present invention comprises a matrix with a low SiO2 / Al2O3 molar ratio and a combination of specific stabilizing and activity-regulating elements, the catalytic cracking catalyst has a large total pore volume and a suitable pore distribution. It still has high micro-reaction activity after being treated at 800°C and 100% steam for 17 hours, and even when the molecular sieve content is low, the catalyst still has high activity. When applied to heavy oil catalytic cracking reactions, it is particularly beneficial for the efficient diffusion of inferior oil macromolecules, enhances resistance to heavy metal contamination, enhances heavy oil conversion capacity, increases light oil yield, and reduces coke yield. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof; wherein:

[0026] Figure 1 shows the pore distribution of the catalytic cracking catalyst prepared in Example 1;

[0027] Figure 2 shows the pore distribution of the catalytic cracking catalyst prepared in Comparative Example 1;

[0028] Figure 3 shows the pore distribution of the catalytic cracking catalysts prepared in Example 9 and Comparative Example 7. Detailed Implementation

[0029] The specific embodiments of the present invention will be described in detail below. However, it should be noted that the scope of protection of the present invention is not limited to these specific embodiments, but is determined by the claims.

[0030] Any specific numerical value (including the endpoints of a range) disclosed in this specification is not limited to its exact value, but should be understood to also include values ​​close to that exact value, such as all possible values ​​within ±5% of that exact value. Furthermore, with respect to the disclosed numerical range, one or more new numerical ranges can be obtained by arbitrarily combining the endpoint values ​​of the range, the endpoint values ​​with specific point values ​​within the range, and the specific point values ​​themselves; these new numerical ranges should also be considered as specifically disclosed in this specification.

[0031] Unless otherwise stated, the terms used in this specification have the same meaning as commonly understood by those skilled in the art. If a term is defined in this specification and its definition differs from the common understanding in the art, the definition in this specification shall prevail.

[0032] In this specification, the pore volume, specific surface area, and pore size distribution of the catalyst were determined by nitrogen physical adsorption.

[0033] In this specification, except where expressly stated, any matters or issues not mentioned are directly applicable to aspects known in the art without any modifications. Furthermore, any implementation described herein can be freely combined with one or more other implementations described herein, and the resulting technical solutions or concepts are considered part of the original disclosure or original record of this invention, and should not be regarded as new content not disclosed or anticipated in this specification, unless those skilled in the art consider such combination clearly unreasonable.

[0034] All patent and non-patent literature mentioned in this specification, including but not limited to textbooks and journal articles, are incorporated in full by way of citation.

[0035] In this specification, the term "comprising" is synonymous with "including" and "containing" and is inclusive or open-ended, without excluding other elements not stated. It should be understood that the term "comprising" encompasses the exclusive and closed term "consisting of". Unless otherwise specified, percentages given in this specification are by weight. In this specification, the expression "substantially" may, depending on the context, mean at least 80% by weight or at least 80 mol% of the total amount; the expression "mainly" may, depending on the context, mean at least 60% by weight or at least 60 mol% of the total amount.

[0036] As a first series of technical solutions according to a first aspect of the present invention, the present invention provides a catalytic cracking catalyst (hereinafter referred to as "first series catalytic cracking catalyst"), wherein, based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 5-40 wt% molecular sieve, 5-40 wt% clay on a dry basis, 5-35 wt% silicon species based on SiO2, 30-75 wt% aluminum species based on Al2O3, 0.5-5 wt% stabilizing element based on oxide, and 0.5-10 wt% activity regulating element based on oxide; the content ratio of the silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.05-2; wherein the stabilizing element is selected from at least one of Group IIIB elements and Group IVB elements, and the activity regulating element is selected from at least one of Mg and P.

[0037] According to a preferred embodiment of the first series of catalytic cracking catalysts, based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 10-35 wt% molecular sieve, 10-35 wt% clay on a dry basis, 6-30 wt% silicon species as SiO2, 35-70 wt% aluminum species as Al2O3, 1-4 wt% stabilizing elements as oxides, and 1-8 wt% activity regulating elements as oxides. For example, in the first series of catalytic cracking catalysts, the content of molecular sieves can be 15 wt%, 20 wt%, 25 wt%, or 30 wt%, and / or, the content of clay on a dry basis can be 15 wt%, 20 wt%, 25 wt%, or 30 wt%; and / or, the content of silicon species based on SiO2 can be 8 wt%, 10 wt%, 15 wt%, 20 wt%, or 25 wt%; and / or, the content of aluminum species based on Al2O3 can be 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, or 65 wt%; and / or, the content of stabilizing elements based on oxides can be 2 wt% or 3 wt%; and / or, the content of activity-regulating elements based on oxides can be 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, or 7 wt%. Using the above-preferred contents of each component is beneficial for fully utilizing the synergistic effect of each component, thereby improving the catalytic performance of the catalytic cracking catalyst.

[0038] For the first series of catalytic cracking catalysts, the total pore volume of the catalytic cracking catalyst, as determined by the low-temperature nitrogen adsorption method, is not less than 0.5 mL / g, wherein the pore volume of pores with a diameter of 10-100 nm accounts for more than 80% of the total pore volume; and / or, the microreaction activity of the catalytic cracking catalyst after hydrothermal treatment, especially after treatment at 800°C and 100% water vapor for 17 hours, is not less than 50, preferably not less than 60, for example 62, 65 or 70.

[0039] As a second series of technical solutions according to the first aspect of the present invention, the present invention provides a catalytic cracking catalyst (hereinafter referred to as "second series catalytic cracking catalyst"), wherein, based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 5-40 wt% molecular sieve, 5-40 wt% clay on a dry basis, 5-35 wt% silicon species based on SiO2, 30-75 wt% aluminum species based on Al2O3, 0.5-15 wt% stabilizing element based on oxides, and 0.5-10 wt% activity regulating element based on oxides; and the content ratio of the silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.05-2; wherein the stabilizing element is selected from Mg, and the activity regulating element is selected from at least one of P, B, Fe, Group IIIB elements and Group IVB elements.

[0040] According to a preferred embodiment of the second series of catalytic cracking catalysts, the catalytic cracking catalyst comprises, based on dry weight, 10-35 wt% molecular sieve, 10-35 wt% clay on a dry basis, 6-30 wt% silicon species as SiO2, 35-70 wt% aluminum species as Al2O3, 1-10 wt% Mg as oxide, and 1-8 wt% activity regulating elements as oxide. For example, in the second series of catalytic cracking catalysts, the content of molecular sieves can be 15 wt%, 20 wt%, 25 wt%, or 30 wt%, and / or, the clay content on a dry basis can be 15 wt%, 20 wt%, 25 wt%, or 30 wt%; and / or, the content of silicon species based on SiO2 can be 8 wt%, 10 wt%, 15 wt%, 20 wt%, or 25 wt%; and / or, the content of aluminum species based on Al2O3 can be 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, or 65 wt%; and / or, the content of Mg based on MgO can be 2 wt%, 3 wt%, 5 wt%, 6 wt%, or 7 wt%; and / or, the content of activity regulating elements based on oxides can be 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, or 7 wt%. Using the above-mentioned preferred content of each component is beneficial to fully exert the synergistic effect of each component, thereby improving the catalytic performance of the catalytic cracking catalyst.

[0041] For the second series of catalytic cracking catalysts, the total pore volume of the catalytic cracking catalyst, as determined by the low-temperature nitrogen adsorption method, is not less than 0.5 mL / g, wherein the pore volume of pores with a diameter of 10-100 nm accounts for more than 80% of the total pore volume.

[0042] The micro-reaction activity of the second series of catalytic cracking catalysts after hydrothermal treatment at 800°C and 100% steam for 17 hours is not less than 60, preferably not less than 65, for example 66, 68, and 70. As a review, the micro-reaction activity of the catalytic cracking catalyst after treatment at 800°C and 100% steam for 17 hours was determined by the following method: the catalytic cracking catalyst was aged in an atmosphere of 800°C and 100% steam for 17 hours, and then the catalyst was removed and subjected to micro-reaction activity testing. The micro-reaction activity of the catalytic cracking catalyst was evaluated using the RIPP 92-90 standard method (see *Analytical Methods in Petrochemical Industry* (RIPP Test Methods), edited by Yang Cuiding et al., Science Press, 1990), wherein the catalyst loading was 5.0 g, the reaction temperature was 460°C, the feedstock was straight-run light diesel oil with a distillation range of 235-337°C, the product composition was analyzed by gas chromatography, and the micro-reaction activity of the light oil was calculated based on the product composition.

[0043] The catalytic cracking catalyst according to the present invention maintains high micro-reaction activity under the above-mentioned extreme hydrothermal treatment conditions. Combined with its specific macroporous structure, it is beneficial to enhance its heavy oil conversion capacity, reduce the generation of by-product coke, and thus improve the yield of light oil.

[0044] Since the catalytic cracking catalyst according to the present invention contains a matrix having a SiO2 / Al2O3 molar ratio of less than 2, and stabilizing elements and activity regulating elements distributed in a specific manner, the catalytic cracking catalyst of the present invention has a large total pore volume, a suitable pore distribution, and high microreactor activity and stability, making it particularly suitable for catalytic cracking reactions of heavy oil, improving resistance to heavy metal contamination and heavy oil conversion capacity, thereby increasing the selectivity of light oil and reducing coke yield.

[0045] In the first series of catalytic cracking catalysts and the second series of catalytic cracking catalysts, the stabilizing element is contained in the catalyst matrix and is distributed almost uniformly inside the catalyst microspheres, while the activity regulating element is mainly (e.g., greater than 65%, greater than 75%, greater than 90%, greater than 95%, or even greater than 99%) loaded on the surface of the catalyst microspheres and optionally in small amounts (e.g., less than 35%, less than 25%, less than 10%, or less than 5%, or even less than 1%) loaded in the pores of a surface layer with a particularly small thickness (e.g., no more than 1 micrometer).

[0046] The inventors have surprisingly discovered that, compared to catalysts with a high SiO2 / Al2O3 molar ratio in the prior art, the catalytic cracking catalyst according to the present invention, which contains a matrix with a SiO2 / Al2O3 molar ratio of less than 2, can form a larger total pore volume and a suitable pore distribution. This is beneficial to improving the catalytic activity of the catalyst and to the transport of inferior oil, thereby achieving efficient conversion of heavy oil and low coke yield in the catalytic cracking process.

[0047] According to one embodiment of the first aspect described above, the total amount of silicon and aluminum species can vary within a wide range, as long as the respective amounts of silicon and aluminum species in the catalytic cracking catalyst meet the aforementioned range. Preferably, the total amount of silicon and aluminum species, calculated as oxides, is 45-90% by weight, more preferably 50-80% by weight, for example, it can be 46% by weight, 50% by weight, 55% by weight, 60% by weight, 65% by weight, 70% by weight, 75% by weight, 80% by weight, 85% by weight, or 89% by weight, and any value within the range of any two of the above values. Using the above-mentioned preferred amounts of silicon and aluminum species is beneficial for further endowing the catalytic cracking catalyst with a rich macroporous structure and excellent activity.

[0048] According to one embodiment of the first aspect described above, the total pore volume of the catalytic cracking catalyst according to the present invention, determined by low-temperature nitrogen adsorption, is 0.6-1.5 mL / g, wherein the pore volume with a diameter of 10-100 nm accounts for 85%-99% of the total pore volume. For example, the total pore volume of the catalytic cracking catalyst can be 0.7 mL / g, 0.8 mL / g, 1 mL / g, 1.1 mL / g, 1.3 mL / g, or 1.4 mL / g, or any value within any range of any two of the above values, and / or, the pore volume with a diameter of 10-100 nm can account for 86%, 87%, 89%, 91%, 93%, 95%, 97%, or 98% of the total pore volume, or any value within any range of any two of the above values. The catalytic cracking catalyst according to the present invention possesses both a large total pore volume and a suitable pore distribution, which is beneficial for improving the activity of the catalyst, thereby enabling the catalyst to exhibit excellent heavy oil catalytic cracking capability, high light oil selectivity, and low coke yield.

[0049] In this specification, the pore volume of the catalytic cracking catalyst was determined by a low-temperature nitrogen adsorption method. For review, this method included: using a Micromeritics ASAP 2405N V1.01 automated adsorption analyzer, low-temperature static nitrogen adsorption capacity method, with the sample at 1.33 × 10⁻⁶ pores. -2The sample was degassed under vacuum at 300℃ for 4 hours using N2 as the adsorption medium, and the adsorption-desorption isotherm was measured at 77.4K. The specific surface area of ​​the sample was calculated using the BET formula, and the volume of N2 adsorbed by the sample at a relative pressure p / p0 = 0.98 was measured and converted to liquid nitrogen volume, i.e., the total pore volume. Pore distribution was determined according to SH / 0572 (ASTM D4641) standard, and the pore volume of the 10-100 nm pore portion of the sample was calculated using the BJH desorption branch.

[0050] The catalytic cracking catalyst according to the invention also has improved mechanical strength, with a wear index not exceeding 2.5 m% / h (mass % / hour), preferably not exceeding 2.0 m% / h, for example 0.5 m% / h, 1.0 m% / h or 1.5 m% / h.

[0051] According to one embodiment of the first aspect described above, the most probable pore size of the catalytic cracking catalyst according to the present invention is 10-40 nm, preferably 13-35 nm, more preferably 15-30 nm, for example, it can be 11 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm or 39 nm, and any value within the range of any two of the above values. A most probable pore size within this range is beneficial for the diffusion of inferior oils and the capacity to contain heavy metals, thereby improving catalytic performance and preventing heavy metal contamination.

[0052] According to one embodiment of the first aspect described above, the particles of the catalytic cracking catalyst according to the invention are substantially in the form of microspheres having a sphericity of 0.8 or higher, the particle size of which can vary over a wide range, preferably substantially between 1 and 150 micrometers, and the average particle size is 60-90 micrometers, preferably 65-85 micrometers. For recap, in this specification, the sphericity of the catalyst microspheres represents the ratio of the surface area of ​​a sphere of the same volume to the surface area of ​​the catalyst microspheres, which is measured by conventional methods in the art; and the term "average particle size" here refers to the number-average diameter of the particles, and is measured by conventional methods in the art by selecting a certain number of sample particles, which will not be elaborated further here.

[0053] For the catalytic cracking catalyst according to the present invention, the silicon-to-aluminum ratio of the included molecular sieve can vary within a wide range; preferably, the SiO2 / Al2O3 molar ratio of the molecular sieve is 4-100:1, more preferably 5-50:1. Using a molecular sieve with the above-mentioned SiO2 / Al2O3 molar ratio is beneficial for further optimizing the pore structure of the catalytic cracking catalyst and improving its catalytic activity.

[0054] For the catalytic cracking catalyst according to the present invention, there is no particular limitation on the type of molecular sieve; it can be any molecular sieve conventionally used in the art, as long as the SiO2 / Al2O3 molar ratio meets the aforementioned range. Preferably, the molecular sieve is selected from at least one of γ-zeolite, MFI-type zeolite, and β-zeolite. There is no particular limitation on the type of γ-zeolite; various γ-zeolite molecular sieves conventionally used in the art can be used in the present invention. Preferably, the γ-zeolite is selected from at least one of HY, REY, REHY, USY, REUSY, and PREUSY. Using the above-preferred γ-zeolite molecular sieve is beneficial for improving catalytic efficiency, increasing light oil yield, and reducing the yield of by-product coke.

[0055] The type of clay contained in the catalytic cracking catalyst according to the present invention is not particularly limited, and various clays conventionally used in the art can be used in the present invention. Preferably, the clay is selected from at least one of kaolin, bentonite, montmorillonite, sepiolite, diatomite, attapulgite, attapulgite, and halloysite, with kaolin being the most preferred. Using the above-mentioned preferred clay is beneficial for further optimizing the pore structure and pore distribution of the catalytic cracking catalyst and improving its wear resistance.

[0056] For the catalytic cracking catalyst according to the present invention, the type of stabilizing element can be selected from a wide range, for example, the stabilizing element is selected from at least one of group IIIB elements and / or group IVB elements, preferably selected from at least one of La, Ce, Y, Zr and Ti, more preferably selected from at least one of La, Ce and Zr; or, for example, the stabilizing element is selected from Mg.

[0057] For the catalytic cracking catalyst according to the present invention, the activity regulating element can be selected according to the stabilizing element used; specifically, when the stabilizing element is selected from group IIIB and / or group IVB elements, preferably at least one of La, Ce, Y, Zr and Ti, the activity regulating element is selected from at least one of Mg and P; or when the stabilizing element is selected from Mg, the activity regulating element is selected from at least one of P, B, Fe, group IIIB and group IVB elements, more preferably at least one of P, B, La, Ce, Y, Zr, Ti and Fe. Using the above combination of stabilizing and activity regulating elements is beneficial for stabilizing the pore structure of the catalytic cracking catalyst, synergistically optimizing the activity of the catalyst's macroporous structure, improving the selectivity of light oil products, and reducing coke yield.

[0058] As a first series of technical solutions of the second aspect of the present invention, the present invention provides a method for preparing the first series of catalytic cracking catalysts (hereinafter referred to as the "first series preparation method"), the method comprising the following steps:

[0059] (1) In the presence of a solvent, a silicon source, an aluminum source, and an optional acid are uniformly mixed to obtain a silica-alumina gel, and a stabilizing element source is mixed with the silica-alumina gel to obtain a mixed gel.

[0060] (2) Adjust the pH of the mixed gel to 9-12 and subject the mixed gel to aging treatment to obtain a stabilized mixed gel;

[0061] (3) The obtained stabilized mixed gel is mixed with clay and molecular sieve to obtain a slurry, which is then spray-dried and optionally calcined to obtain catalyst microspheres.

[0062] (4) Allow the catalyst microspheres to undergo ammonium ion exchange, and

[0063] (5) Loading an activity-regulating element onto ammonium ion-exchanged catalyst microspheres; optionally filtering, drying, and calcining the catalytic cracking catalyst microspheres loaded with the activity-regulating element; to obtain a catalytic cracking catalyst;

[0064] The amount of the stabilizing element source, silicon source, aluminum source, clay, molecular sieve, and activity regulating element source added is such that the obtained catalytic cracking catalyst comprises, based on the dry weight of the catalytic cracking catalyst: 5-40 wt% molecular sieve, 5-40 wt% clay on a dry basis, 5-35 wt% silicon species (calculated as SiO2), 30-75 wt% aluminum species (calculated as Al2O3), 0.5-5 wt% stabilizing element (calculated as oxide), and 0.5-10 wt% [unclear text - possibly a reference to a specific ingredient or component]. The active regulating element is % based on oxides; the content ratio of silicon species and aluminum species based on SiO2 / Al2O3 molar ratio is 0.05-2:1 (i.e., Si / Al molar ratio is 0.025-1:1), preferably 0.2-1.5:1 (i.e., Si / Al molar ratio is 0.1-0.75:1); wherein the stabilizing element is selected from at least one of group IIIB and group IVB elements, and the active regulating element is selected from at least one of Mg and P.

[0065] According to one embodiment of the first series of preparation methods, the stabilizing element selected from Group IIIB and Group IVB elements is selected from at least one of La, Ce, Y, Zr, and Ti, preferably from at least one of La, Ce, and Zr, and the activity regulating element is selected from at least one of Mg and P. The combination of the above-mentioned preferred stabilizing and activity regulating elements can work synergistically to improve the efficiency of catalytic cracking reactions, increase the selectivity of light oil products, and reduce coke yield.

[0066] According to one embodiment of the first series of preparation methods, in the preparation method, the amount of the stabilizing element source, silica-alumina gel, clay, molecular sieve, and activity regulating element source added is such that the obtained catalytic cracking catalyst comprises, based on the dry weight of the catalytic cracking catalyst: 10-35 wt% molecular sieve, 10-35 wt% clay on a dry basis, 5-35 wt% silicon species based on SiO2, 30-75 wt% aluminum species based on Al2O3, 1-4 wt% stabilizing element based on oxides, and 1-8 wt% activity regulating element based on oxides; wherein the content ratio of silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.2-1.5.

[0067] According to one embodiment of the first series of preparation methods, in step (1) of the preparation method, the solid content of the silica-alumina gel is 5-40% by weight, for example, it can be 6% by weight, 10% by weight, 15% by weight, 20% by weight, 25% by weight, 30% by weight, 35% by weight, or 39% by weight, or any value within the range of any two of the above values. Using the above-preferred solid content of the silica-alumina gel is beneficial to ensuring uniform mixing and sufficient reaction of the components, optimizing the aging treatment effect, and improving the catalytic performance of the catalytic cracking catalyst.

[0068] According to one embodiment of the first series of preparation methods, in step (1) of the preparation method, the preparation method of the silica-alumina gel includes: mixing a solvent, an aluminum source, and a silicon source to obtain a mixed solution, and then mixing the mixed solution with an acid to obtain a silica-alumina gel; or, first mixing an aluminum source solution with an acid, and then adding a silicon source for mixing to obtain a silica-alumina gel. The above gel preparation methods are beneficial for forming silica-alumina gels with uniform structure and good performance. In the preparation method of the present invention, the solvent of the aluminum source solution is preferably water. For the preparation method, there are no particular limitations on the mixing method and conditions, as long as uniform mixing is ensured. Preferably, the duration of each mixing is independently 0.5-5 hours.

[0069] According to one embodiment of the first series of preparation methods, in the prepared catalyst, the content ratio of silicon species and aluminum species in the matrix other than molecular sieve and clay, expressed as SiO2 / Al2O3 molar ratio, is preferably 0.3-1.4, for example, it can be 0.4, 0.6, 0.8, 1, 1.2 or 1.3, or any value within the range of any two of the above values.

[0070] According to one embodiment of the first series of preparation methods, there is no particular limitation on the type of aluminum source, and various aluminum sources conventionally used in the art can be used. Preferably, the aluminum source is selected from at least one of aluminum sol, aluminum sulfate, aluminum isopropoxide, aluminum chloride, aluminum nitrate, boehmite, alumina, aluminum hydroxide, and sodium aluminate, and is more preferably aluminum sulfate and / or aluminum sol.

[0071] According to one embodiment of the first series of preparation methods, there is no particular limitation on the type of silicon source, and various silicon sources conventionally used in the art can be used. Preferably, the silicon source is selected from at least one of water glass, alkaline silica sol, acidic silica sol, tetraethyl orthosilicate, and tetramethoxysilane, and is more preferably water glass and / or alkaline silica sol.

[0072] According to one embodiment of the first series of preparation methods, in step (1), the amount of acid can vary within a wide range; preferably, the amount of acid is such that the pH of the mixture obtained after mixing is 1-4, for example, 1.5, 2, 3 or 3.5, and any value within the range of any two of the above values. Within the above preferred pH range, the silicon source and the aluminum source can undergo an effective polycondensation reaction to form a stable silica-alumina gel.

[0073] According to one embodiment of the first series of preparation methods, there is no particular limitation on the type of acid, and various substances that can provide acidity commonly used in the art can be used. The acid can be an inorganic acid and / or an organic acid, preferably selected from at least one of hydrochloric acid, sulfuric acid, nitric acid, acetic acid, and citric acid.

[0074] According to one embodiment of the first series of preparation methods, the source of the stabilizing element is a compound containing a stabilizing element; the type of compound containing the stabilizing element can be selected from a wide range, preferably at least one of the nitrate, chloride, sulfate, phosphate, acetate and alkoxide of the stabilizing element, more preferably nitrate and / or chloride.

[0075] According to one embodiment of the first series of preparation methods, in step (1), there are no particular limitations on the method, conditions, and equipment for performing the mixing, as long as the stabilizing element source and the silica-alumina gel are mixed uniformly. Preferably, the duration of each mixing is 0.5-5 hours.

[0076] According to one embodiment of the first series of preparation methods, in step (2), there are no particular limitations on the conditions for carrying out the aging treatment; preferably, the conditions for carrying out the aging treatment include: a temperature of 10-100℃, preferably 20-80℃; and a time of 1-24 hours, preferably 4-20 hours. Using the above-mentioned preferred aging treatment conditions is beneficial for further consolidating the skeletal structure of the silica-alumina gel, and also for the uniform distribution and firm binding of stabilizing elements in the gel.

[0077] According to one embodiment of the first series of preparation methods, step (2) further includes: before aging treatment, mixing the mixed slurry with an alkali to obtain a mixture with a pH of 9-12, for example, 9, 9.5, 10, 10.5, 11, 11.5, or 12, or any value within the range of any two of the above values. There is no particular limitation on the type of alkali used; various substances conventionally used in the art that can provide alkalinity can be used in this invention. Preferably, the alkali is selected from at least one of ammonia, sodium hydroxide, sodium carbonate, and sodium aluminate. The amount of alkali used can vary within a wide range. Using the above-mentioned preferred pH range helps ensure that the silica-alumina gel forms a stable structure during the aging treatment, thereby improving the catalytic performance of the catalytic cracking catalyst. The alkali treatment helps to form a more stable silica-alumina gel.

[0078] According to one embodiment of the first series of preparation methods, there are no particular limitations on the method and conditions for spray drying in step (3), and conventional spray drying methods and conditions used in the art can be adopted. Preferably, the tail gas temperature of the spray drying is 100-300℃, more preferably 120-200℃. The above spray drying conditions are beneficial for atomizing the slurry into tiny droplets and rapidly drying them into microspheres, thereby obtaining catalyst microspheres with good morphology and further improving the catalytic cracking performance of the prepared catalytic cracking catalyst. Preferably, the catalytic cracking catalyst microspheres obtained by spray drying have a sphericity greater than 0.8, preferably greater than 0.9, and an average particle size of 60-90 micrometers, preferably 65-85 micrometers. As a recap, in this specification, the sphericity of the catalyst microspheres is calculated by the ratio of the surface area of ​​a sphere of the same volume as the catalyst microsphere to the surface area of ​​the catalyst microsphere. The surface area of ​​the microspheres is measured by conventional methods in the art, which will not be described in detail here.

[0079] According to one embodiment of the first series of preparation methods, step (3) may further include calcining the spray-dried product. The calcination conditions can be selected within a wide range; preferably, the calcination conditions include: a temperature of 300-600°C, a time of 0.5-5 hours, and a heating rate of 2-10°C / minute.

[0080] According to one embodiment of the first series of preparation methods, there are no particular limitations on the method and conditions for mixing the stabilized mixed gel, clay, and molecular sieve in step (3), as long as the stabilized mixed gel, clay, and molecular sieve are mixed evenly. Preferably, the mixing time is 0.5-5 hours.

[0081] According to one embodiment of the first series of preparation methods, there is no particular limitation on the type of active regulating element source used; preferably, the active element source is a soluble compound containing an active regulating element, preferably selected from at least one of magnesium sulfate, magnesium nitrate, magnesium chloride, magnesium acetate, magnesium oxalate, orthophosphoric acid, phosphorous acid, ammonium phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate and pyrophosphate, more preferably selected from at least one of magnesium sulfate, magnesium nitrate, magnesium oxalate, ammonium dihydrogen phosphate and diamine hydrogen phosphate.

[0082] According to one embodiment of the first series of preparation methods, the ammonium ion exchange in step (4) can be carried out using conventional methods in the art. Specifically, the ammonium ion exchange is performed as follows: the catalyst microspheres are mixed and contacted with the ammonium salt solution under stirring, so that the Na2O content in the catalyst is not higher than 0.3% by weight. For retrospect, the sodium oxide content on the surface of the catalyst microspheres is determined using the method Q / SH 361906-2018 (Q / SH 3360-205). Preferably, the conditions for carrying out the ammonium ion exchange include: a temperature of 20-100°C, preferably 20-80°C; and a time of 10-120 minutes. In this invention, there is no particular limitation on the type of ammonium salt, as long as it enables the catalyst microspheres and the ammonium salt to exchange ions. Preferably, the ammonium salt used for ammonium ion exchange is selected from at least one of ammonium chloride, ammonium sulfate, ammonium bisulfate, ammonium nitrate, ammonium carbonate, ammonium bicarbonate, ammonium oxalate, and ammonium phosphate, and more preferably from at least one of ammonium chloride, ammonium sulfate, and ammonium oxalate.

[0083] According to one embodiment of the first series of preparation methods, in step (4), when performing ammonia ion exchange, the ratio of the amount of the catalytic cracking catalyst microspheres to the ammonium salt can vary within a wide range; preferably, the ratio of the amount of the catalytic cracking catalyst microspheres to the ammonium salt by mass is 1:0.01-0.5, and more preferably 1:0.05-0.2.

[0084] According to one embodiment of the first series of preparation methods, in step (4), during ammonia ion exchange, the amounts of the catalytic cracking catalyst microspheres and the solvent can vary within a wide range; preferably, the mass ratio of the catalytic cracking catalyst microspheres to the solvent is 1:2-20, more preferably 1:5-10. The solvent used in this invention is preferably water.

[0085] According to one embodiment of the first series of preparation methods, in step (5), an activity regulating element is loaded onto the catalyst microspheres that have undergone ammonium ion exchange to optimize the active sites on the surface of the catalyst microspheres. This is beneficial to improve the selectivity of light oil products while reducing the coke yield.

[0086] According to one embodiment of the first series of preparation methods, there is no particular limitation on the loading method of the activity regulating element in step (5); preferably, the loading of the activity regulating element is carried out in the following manner: in the presence of a solvent, the source of the activity regulating element is mixed and contacted with the catalyst microspheres that have undergone ammonium ion exchange, and impregnation and / or ion exchange are performed; wherein, there is no particular limitation on the impregnation method, and impregnation methods and conditions conventionally used in the art can be adopted, so that the activity regulating element is loaded on the surface of the catalyst microspheres and optionally in the pores of the surface layer. Preferably, the impregnation method is a saturated impregnation method. More preferably, the catalyst microspheres that have undergone ammonium ion exchange are contacted and impregnated with a solution of a soluble compound containing the activity regulating element. Preferably, the conditions for carrying out the contact impregnation include: a temperature of 20-100°C, preferably 20-80°C; and a time of 10 minutes or more, preferably 20-120 minutes, as long as the activity regulating element in the solution is substantially completely loaded onto the microspheres. The present invention does not have any particular limitation on the type of soluble compound containing the active regulating element, and can use compounds conventional in the art.

[0087] According to one embodiment of the first series of preparation methods, in step (5), the ratio of the ammonium ion-exchanged catalyst microspheres to the active regulating element source can vary within a wide range; preferably, the ratio of the ammonium ion-exchanged catalyst microspheres to the active regulating element source by mass, calculated as oxides, is 1:0.005-0.1, more preferably 1:0.01-0.08.

[0088] According to one embodiment of the first series of preparation methods, in step (5), the ratio of the ammonium ion-exchanged catalyst microspheres to the solvent can vary within a wide range; preferably, the mass ratio of the ammonium ion-exchanged catalyst microspheres to the solvent is 1:1-20, more preferably 1:2-10.

[0089] According to one embodiment of the first series of preparation methods, in step (5), when the active regulating element is two or more elements, the loading of the active regulating element can be carried out in one step or in multiple steps, and the present invention does not have any particular limitation on this.

[0090] According to one embodiment of the first series of preparation methods, in step (5), there are no particular limitations on the method and conditions for calcination; preferably, the conditions for calcination include: a temperature of 400-600℃, preferably 450-550℃; and a time of 0.5-3 hours, preferably 1-2.5 hours.

[0091] According to one embodiment of the first series of preparation methods, step (5) may further include: filtering and drying the catalyst microspheres loaded with the activity regulating element before calcination; wherein the method and conditions for performing the filtration and drying are not particularly limited, and can be the filtration and drying methods and conditions conventionally used in the art. Preferably, the drying temperature is 80-200°C, and the time is 2-24 hours.

[0092] As a second series of technical solutions of the second aspect of the present invention, the present invention provides a method for preparing the second series of catalytic cracking catalysts (hereinafter referred to as the "second series preparation method"), the method comprising the following steps:

[0093] (1) In the presence of a solvent, a silicon source, an aluminum source, a magnesium source and an optional acid are uniformly mixed to obtain a silicon-aluminum-magnesium mixed gel.

[0094] (2) The pH of the obtained silicon-aluminum-magnesium mixed gel is adjusted to 9-12, and the silicon-aluminum-magnesium mixed gel is subjected to aging treatment to obtain a stabilized mixed gel.

[0095] (3) The obtained stabilized mixed gel is mixed with clay and molecular sieve to obtain a slurry, which is then spray-dried and optionally calcined to obtain catalyst microspheres.

[0096] (4) Allow the catalyst microspheres to undergo ammonium ion exchange, and

[0097] (5) Loading an activity regulating element onto a catalyst microsphere that has undergone ammonium ion exchange; optionally filtering, drying and calcining the catalytic cracking catalyst microsphere loaded with the activity regulating element to obtain a catalytic cracking catalyst;

[0098] The magnesium source, silicon source, aluminum source, clay, molecular sieve, and activity regulating element source are added in such amounts that the obtained catalytic cracking catalyst comprises, based on the dry weight of the catalytic cracking catalyst: 5-40 wt% molecular sieve, 5-40 wt% clay on a dry basis, 5-35 wt% silicon species (SiO2), 30-75 wt% aluminum species (Al2O3), 0.5-15 wt% stabilizing element (oxide), and 0.5-10 wt% activity regulating element (oxide); the content ratio of silicon species and aluminum species, based on the SiO2 / Al2O3 molar ratio, is 0.05-2; wherein Mg is used as a stabilizing element, and the activity regulating element is selected from at least one of P, B, Fe, Group IIIB elements, and Group IVB elements.

[0099] According to the second series of preparation methods, a catalytic cracking catalyst with abundant macroporous structure, high catalytic activity, and high activity stability is obtained by preparing a silica-alumina-magnesium mixed gel, adjusting the silica-alumina-magnesium mixed gel to a specific pH range for aging treatment, and loading activity-regulating elements on the surface of catalyst microspheres and optionally in the pores of the surface layer. The preparation method allows for the preparation of a catalytic cracking catalyst containing specific amounts of stabilizing element magnesium and specific amounts of activity-regulating elements, possessing abundant macroporous structure, high microreaction activity, and a low SiO2 / Al2O3 molar ratio. When this catalytic cracking catalyst is used in heavy oil catalytic cracking methods, it exhibits excellent catalytic performance.

[0100] According to one embodiment of the second series of preparation methods, in step (1), the amount of magnesium source, silica-alumina gel, clay, molecular sieve and active regulating element source added is such that the obtained catalytic cracking catalyst contains, based on the dry weight of the catalytic cracking catalyst: 10-35 wt% molecular sieve, 10-35 wt% clay on a dry basis, 5-35 wt% silicon species based on SiO2, 30-75 wt% aluminum species based on Al2O3, 1-10 wt% Mg based on MgO and 1-8 wt% active regulating element based on oxides; the content ratio of silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.2-1.5:1.

[0101] According to one embodiment of the second series of preparation methods, in the prepared catalyst, the content ratio of silicon species and aluminum species in the matrix other than molecular sieve and clay, expressed as SiO2 / Al2O3 molar ratio, is preferably 0.3-1.4, for example, it can be 0.4, 0.6, 0.8, 1, 1.2 or 1.3, or any value within the range of any two of the above values.

[0102] According to one embodiment of the second series of preparation methods, the active regulating element is selected from at least one of P, B, La, Ce, Y, Zr, Ti, and Fe, preferably from at least one of P, B, La, and Ce. Using the above-mentioned preferred active regulating element is more conducive to synergistic effects with magnesium, improving catalytic cracking reaction efficiency, increasing the selectivity of light oil products, and reducing coke yield.

[0103] According to one embodiment of the second series of preparation methods, by preparing a silicon-aluminum-magnesium mixed gel in step (1) so that magnesium element exists in the gel skeleton, it is beneficial to improve the catalytic activity of the catalyst, enhance the stability of the catalyst, and optimize the pore structure, thereby making the catalytic cracking catalyst have a better catalytic effect in the heavy oil catalytic cracking reaction.

[0104] According to one embodiment of the second series of preparation methods, in step (1), the solid content of the silicon-aluminum-magnesium mixed gel is 5-40% by weight, for example, it can be 6% by weight, 10% by weight, 15% by weight, 20% by weight, 25% by weight, 30% by weight, 35% by weight, or 39% by weight, and any value within the range of any two of the above values, preferably 5-35% by weight. Using the above-mentioned preferred solid content of the silicon-aluminum-magnesium mixed gel is beneficial to ensuring uniform mixing and sufficient reaction of each component, optimizing the aging treatment effect, improving the catalytic performance of the catalytic cracking catalyst, and optimizing the catalytic effect.

[0105] According to one embodiment of the second series of preparation methods, in step (1), the solvent, silicon source, aluminum source, magnesium source, and acid can be mixed in one step, or the solvent, silicon source, aluminum source, magnesium source, and acid can be mixed in multiple steps. Preferably, the solvent, aluminum source, and silicon source are first mixed to obtain a mixed solution, the mixed solution is then mixed with the acid, and then the magnesium source is added for mixing. More preferably, the solvent, aluminum source, and acid are mixed, then the silicon source is added for mixing, and then the magnesium source is added for mixing. The above-mentioned preferred preparation methods are beneficial for forming a silicon-aluminum-magnesium mixed gel with a uniform structure and good performance. In the preparation method of the present invention, the solvent is preferably water; the preparation method of the present invention does not particularly limit the equipment, method, and conditions for performing the mixing, as long as uniform mixing is ensured. Preferably, the duration of each mixing is independently 0.5-5 hours.

[0106] According to one embodiment of the second series of preparation methods, in step (1), the type of magnesium source can be selected from a wide range; preferably, the magnesium source is a magnesium-containing compound, preferably selected from at least one of magnesium oxide, magnesium sulfate, magnesium nitrate, magnesium chloride, magnesium oxalate and magnesium acetate, more preferably selected from at least one of magnesium oxide, magnesium sulfate, magnesium nitrate and magnesium acetate.

[0107] According to one embodiment of the second series of preparation methods, in step (1), there is no particular limitation on the type of aluminum source, and various aluminum sources conventionally used in the art can be used. Preferably, the aluminum source is selected from at least one of aluminum sol, aluminum sulfate, aluminum isopropoxide, aluminum chloride, aluminum nitrate, boehmite, alumina, aluminum hydroxide, and sodium aluminate, and is preferably aluminum sulfate and / or aluminum sol.

[0108] According to one embodiment of the second series of preparation methods, in step (1), there is no particular limitation on the type of silicon source, and various silicon sources conventionally used in the art can be used. Preferably, the silicon source is selected from at least one of water glass, alkaline silica sol, acidic silica sol, tetraethyl orthosilicate, and tetramethoxysilane, and is more preferably water glass and / or alkaline silica sol.

[0109] According to one embodiment of the second series of preparation methods, in step (1), the amount of acid used can be selected within a wide range; preferably, the amount of acid used is such that the pH of the mixture obtained after mixing is 1-4, for example, 1.5, 2, 3 or 3.5, and any value within the range of any two of the above values. Within the above preferred pH range, the silicon source and the aluminum source can undergo an effective polycondensation reaction to form a stable silica-alumina gel.

[0110] According to one embodiment of the second series of preparation methods, in step (1), there is no particular limitation on the type of acid, and various substances that can provide acidity commonly used in the art can be used. Preferably, the acid is an inorganic acid and / or an organic acid, preferably selected from at least one of hydrochloric acid, sulfuric acid, nitric acid, acetic acid, and citric acid.

[0111] According to one embodiment of the second series of preparation methods, in step (2), the conditions for the aging treatment can be selected within a wide range; preferably, the conditions for the aging treatment include: a temperature of 10-100℃, more preferably 20-80℃; and a time of 1-24 hours, more preferably 4-20 hours. Using the above-mentioned preferred aging treatment conditions is beneficial for further consolidating the skeletal structure of the silica-alumina gel and for ensuring the uniform distribution and firm binding of stabilizing elements in the gel.

[0112] According to one embodiment of the second series of preparation methods, step (2) further includes: before aging treatment, mixing the mixed slurry with an alkali to make the pH of the resulting mixture 9-12, for example, 9, 9.5, 10, 10.5, 11, 11.5 or 12, and any value within the range of any two of the above values, preferably 9.5-11.5. There is no particular limitation on the type of alkali; various substances conventionally used in the art that can provide alkalinity can be used in this invention; preferably, the alkali is selected from at least one of ammonia, sodium hydroxide, sodium carbonate, and sodium aluminate. The amount of alkali used can vary within a wide range. Using the above-preferred pH range helps ensure that the silica-alumina gel forms a stable structure during the aging treatment, thereby improving the catalytic performance of the catalytic cracking catalyst. The alkali treatment helps to form a more stable silica-alumina-magnesium sol.

[0113] According to one embodiment of the second series of preparation methods, there are no particular limitations on the method and conditions for spray drying in step (3), and conventional spray drying methods and conditions used in the art can be adopted. Preferably, the tail gas temperature of the spray drying is 100-300°C, more preferably 120-200°C. The above spray drying conditions are beneficial for atomizing the slurry into tiny droplets and rapidly drying them into microspheres, thereby obtaining catalyst microspheres with good morphology and further improving the catalytic cracking performance of the prepared catalytic cracking catalyst. Preferably, the catalytic cracking catalyst particles obtained by spray drying are microspheres with a sphericity greater than 0.8, preferably greater than 0.9, and their particle size can have a wide range, for example, 1-150 micrometers, and their average particle size is 60-90 micrometers, preferably 65-85 micrometers. As a recap, in this specification, the sphericity of the catalyst microspheres represents the ratio of the surface area of ​​a sphere of the same volume as the catalyst microspheres to the surface area of ​​the catalyst microspheres, which is measured by conventional methods in the art and will not be repeated here.

[0114] According to one embodiment of the second series of preparation methods, there are no particular limitations on the method and conditions for mixing the stabilized mixed gel with the clay and molecular sieve in step (3), as long as the stabilized mixed gel, clay and molecular sieve are mixed evenly. Preferably, the mixing time is 0.5-5 hours.

[0115] According to one embodiment of the second series of preparation methods, step (3) further includes calcining the spray-dried product. The calcination conditions can be selected within a wide range; preferably, the calcination conditions include: a temperature of 300-600℃, a time of 0.5-5 hours, and a heating rate of 2-10℃ / minute.

[0116] According to one embodiment of the second series of preparation methods, the ammonium ion exchange in step (4) can be carried out using conventional methods in the art. Specifically, the ammonium ion exchange is performed as follows: the catalyst microspheres are mixed and contacted with the ammonium salt solution under stirring, such that the Na2O content in the catalyst microspheres is not higher than 0.3% by weight. For retrospect, the sodium oxide content on the surface of the catalyst microspheres is measured using the method Q / SH 361906-2018 (Q / SH 3360-205). Preferably, the conditions for carrying out the ammonium ion exchange include: a temperature of 20-100°C, preferably 20-80°C; and a time of 10-120 minutes. The present invention does not particularly limit the type of ammonium salt, as long as it enables ion exchange between the catalyst microspheres and the ammonium salt. Preferably, the ammonium salt used for ammonium ion exchange is selected from at least one of ammonium chloride, ammonium sulfate, ammonium bisulfate, ammonium nitrate, ammonium carbonate, ammonium bicarbonate, ammonium oxalate, and ammonium phosphate, more preferably from at least one of ammonium chloride, ammonium sulfate, and ammonium oxalate.

[0117] According to one embodiment of the second series of preparation methods, in step (4), for ammonia ion exchange, the ratio of the amount of the catalytic cracking catalyst microspheres to the ammonium salt can vary within a wide range; preferably, the ratio of the amount of the catalytic cracking catalyst microspheres to the ammonium salt by mass is 1:0.01-0.5, more preferably 1:0.05-0.2.

[0118] According to one embodiment of the second series of preparation methods, in step (4), for ammonia ion exchange, the amounts of the catalytic cracking catalyst microspheres and the solvent can vary within a wide range; preferably, the mass ratio of the catalytic cracking catalyst microspheres to the solvent is 1:2-20, more preferably 1:5-10. Using the above-mentioned preferred mass ratio is beneficial to improving the efficiency of ammonium exchange. The solvent used in this invention is preferably water.

[0119] According to the second series of preparation methods, in step (5), loading the catalyst microspheres that have undergone ammonium ion exchange with active regulating elements is beneficial to increasing the loading of active elements, thereby improving the activity stability of the catalytic cracking catalyst.

[0120] According to one embodiment of the second series of preparation methods, there is no particular limitation on the method of loading the activity regulating element in step (5); preferably, the loading of the activity regulating element is carried out in the following manner: in the presence of a solvent, the activity regulating element source is mixed and contacted with the ammonium ion-exchanged catalyst microspheres for impregnation and / or ion exchange; wherein, there is no particular limitation on the method of impregnation or ion exchange, and the impregnation or ion exchange methods and conditions conventionally used in the art can be adopted, so that the activity regulating element is loaded on the surface of the catalyst microspheres and optionally loaded in the pores of the surface layer. Preferably, the impregnation method is a saturated impregnation method. More preferably, the ammonium ion-exchanged catalyst microspheres are contacted and impregnated with a solution containing a soluble compound (i.e., the activity regulating element source) containing the activity regulating element. Preferably, the conditions for the impregnation include: a temperature of 20-100°C, preferably 20-80°C; and a time of 10 minutes or more, preferably 20-120 minutes, as long as the activity regulating element in the solution is substantially completely loaded onto the microspheres. The present invention does not have any particular limitation on the type of soluble compound containing the active regulating element, and can use compounds conventional in the art.

[0121] According to one embodiment of the second series of preparation methods, the ratio of the ammonium ion-exchanged catalyst microspheres to the activity-regulating element source can vary within a wide range; preferably, the mass ratio of the ammonium ion-exchanged catalyst microspheres to the activity-regulating element source is 1:0.005-0.1, more preferably 1:0.01-0.08. Using the above-mentioned preferred ratio is beneficial for improving the activity stability of the catalytic cracking catalyst and resulting in superior catalytic performance.

[0122] According to one embodiment of the second series of preparation methods, there is no particular limitation on the type of the activity-regulating element source. The type of the activity-regulating element source can be selected from a wide range; preferably, the activity-regulating element source is a soluble compound containing an activity-regulating element. Preferably, the phosphorus source is selected from one or more of orthophosphoric acid, phosphorous acid, ammonium phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, aluminum phosphate, and pyrophosphoric acid; the boron source is selected from boric acid and / or boron oxide; the La, Ce, Y, Zr, Ti, and Fe sources are each independently a salt containing the corresponding metal element, preferably a nitrate and / or chloride.

[0123] According to one embodiment of the second series of preparation methods, in step (5), the ratio of the ammonium ion-exchanged catalyst microspheres to the solvent can vary within a wide range; preferably, the mass ratio of the ammonium ion-exchanged catalyst microspheres to the solvent is 1:1-20, more preferably 1:2-10.

[0124] According to one embodiment of the second series of preparation methods, in step (5), when the active regulating element is two or more elements, the loading of the active regulating element can be carried out in one step or in multiple steps, and the present invention does not have any particular limitation on this.

[0125] According to one embodiment of the second series of preparation methods, in step (5), there are no particular limitations on the method and conditions for carrying out the roasting; preferably, the conditions for carrying out the roasting include: a temperature of 400-600℃, preferably 450-550℃; and a time of 0.5-3 hours, preferably 1-2.5 hours.

[0126] According to one embodiment of the second series of preparation methods, step (5) further includes: if necessary, filtering and drying the catalyst microspheres loaded with the active regulating element before calcination; wherein there are no particular limitations on the method and conditions for performing the drying, and the drying methods and conditions conventionally used in the art can be used. Preferably, the drying temperature is 80-200°C and the time is 0.5-24 hours.

[0127] According to a third aspect of the present invention, the present invention provides a method for catalytic cracking of heavy oil, characterized in that the method comprises contacting and reacting a catalytic cracking catalyst according to the present invention or a catalytic cracking catalyst prepared by the method according to the present invention with heavy oil.

[0128] According to a fourth aspect of the invention, the invention provides the use of the catalytic cracking catalyst for reducing the coke yield or coke selectivity of the catalytic cracking reaction in the catalytic cracking method.

[0129] The catalytic cracking catalyst according to the present invention is particularly suitable for the catalytic cracking reaction of heavy oil. Due to the large total pore volume and suitable pore distribution of the catalytic cracking catalyst, it is particularly beneficial to the efficient diffusion of inferior oil macromolecules, enhances the resistance to heavy metal pollution, improves the conversion capacity of heavy oil, increases the selectivity of light oil, and significantly reduces the selectivity of by-product coke.

[0130] Example

[0131] The present invention will be further illustrated by the following examples, but the present invention is not limited thereto.

[0132] In the following embodiments and comparative examples:

[0133] Unless otherwise specified, room temperature refers to 25±5℃.

[0134] The raw materials used in the preparation of the catalyst are described as follows: kaolin with a solid content of 79 wt%; the rare earth ultrastable Y zeolite REUSY with a solid content of 85 wt%, wherein the molar ratio of silicon oxide to aluminum oxide is 8, and the cell constant is [missing information]. The composition by weight percentage is as follows: Na₂O content is 1.6%, RE₂O₃ content is 12%; aluminum sol has an alumina content of 22% by weight; aluminum sulfate solution has a concentration of 90 g / L as Al₂O₃; boehmite has a solid content of 65%; water glass has a concentration of 250 g / L as SiO₂ and a density of 1.26 g / mL; and alkaline silica sol has a silica content of 30%.

[0135] The specific surface area and pore volume of the catalyst microspheres were determined as follows: A Micromeritics ASAP 2405NV1.01 automated adsorption analyzer (USA) was used, employing the low-temperature static nitrogen adsorption capacity method. The sample surface area was 1.33 × 10⁻⁶. -2 The sample was degassed under vacuum for 4 hours at a pressure of Pa and a temperature of 300℃. Using N2 as the adsorption medium, the adsorption-desorption isotherm of the sample was measured at 77.4K. The specific surface area of ​​the sample was calculated according to the BET formula. The volume of N2 adsorbed by the sample at a relative pressure p / p0 = 0.98 was measured and converted into liquid nitrogen volume, i.e., total pore volume. The pore distribution was calculated using the SH / 0572 (ASTM D4641) standard and the pore volume of the 10-100 nm pore portion of the sample was calculated using the BJH desorption branch.

[0136] The strength of catalytic cracking catalyst is determined as follows: A certain amount of catalyst is placed in a fixed device and milled under a constant airflow for 5 hours. The average percentage of wear in the last four hours (excluding the first hour) is called the catalyst wear index, expressed in m% / h (mass % / hour). The test method and standard are: NB / SH / T 0964-2017.

[0137] The microreactor activity of the catalytic cracking catalyst was determined as follows: The microreactor activity of the light oil sample was evaluated using the standard method of RIPP 92-90 (see "Analytical Methods in Petrochemical Industry" (RIPP Test Methods), edited by Yang Cuiding et al., Science Press, 1990). The catalyst loading was 5.0 g, the reaction temperature was 460 °C, the feed oil was straight-run light diesel oil with a distillation range of 235-337 °C, the product composition was analyzed by gas chromatography, and the microreactor activity of the light oil was calculated based on the product composition.

[0138] Evaluation of the microreactor activity and stability of the catalytic cracking catalyst: The catalytic cracking catalyst was pre-treated with hydrothermal treatment at 800℃ and 100% steam for 17 hours in a fixed-bed aging unit, and then evaluated in an ACE unit. The properties of the feedstock are shown in Table 2, and the reaction temperature and catalyst-to-oil weight ratio are shown in Table 3.

[0139] Conversion rate (%) = Gasoline yield (%) + Liquefied petroleum gas yield (%) + Dry gas yield (%) + Coke yield (%);

[0140] Coke selectivity (%) = Coke yield (%) / Conversion rate (%) × 100%.

[0141] The average particle size of the catalyst microspheres was measured by microscopy. The elemental distribution in the catalyst was determined by SEM-EDS (scanning electron microscopy combined with energy dispersive spectroscopy).

[0142] Unless otherwise specified herein, the other parameters involved in the following embodiments have conventional definitions in the art and are measured by conventional methods in the art, and will not be repeated here.

[0143] The following Examples 1-8 and Comparative Examples 1-6 are used to illustrate the preparation and properties of the first series of catalytic cracking catalysts according to the present invention.

[0144] Example 1

[0145] (1) Add 909 g of aluminum sol to 200 g of deionized water and mix well. Then add hydrochloric acid to the mixture to adjust the pH of the slurry to 3. Add 500 g of water glass solution and stir for 2 hours to obtain a silica-alumina gel with a solid content of 18.6% by weight. Add 21.7 g of lanthanum chloride (LaCl3·6H2O) to the silica-alumina gel and stir for 0.5 hours to obtain a mixed gel.

[0146] (2) Add ammonia to the obtained mixed gel to adjust the pH of the gel to 11, and after aging at 80°C for 6 hours, a stabilized mixed gel is obtained.

[0147] (3) The stabilized mixed gel, 101 g of kaolin and 286 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) were mixed for 2 hours under stirring to obtain a slurry. The slurry was then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers.

[0148] (4) The catalyst microspheres, ammonium sulfate and water were mixed in a mass ratio of 1:0.1:10 to carry out ammonium ion exchange. The mixture was stirred at 60°C for 30 minutes, filtered and repeated twice.

[0149] (5) The ammonium-exchanged catalyst microspheres, deionized water, and 37.1 g of magnesium nitrate were mixed and stirred for 30 minutes at a mass ratio of 1:0.02:5 (catalyst microspheres:MgO:water) to load magnesium ions onto the catalyst microspheres. Measurements showed that the aqueous phase contained almost no magnesium ions. The mixture was then filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 500°C for 2 hours to obtain the catalytic cracking catalyst C1. Analysis showed that magnesium was mainly loaded on the surface of the catalyst microspheres, while lanthanum was uniformly distributed within the catalyst microspheres.

[0150] The pore distribution of the catalytic cracking catalyst C1 prepared in Example 1 is shown in Figure 1.

[0151] The composition and properties of the catalytic cracking catalyst C1 prepared in Example 1 are shown in Table 1.

[0152] Example 2

[0153] (1) Add 2465 g of aluminum sulfate solution to 200 g of deionized water and mix well. Then add hydrochloric acid to the mixture to adjust the pH of the slurry to 3. Add 600 g of water glass solution and stir for 2 hours to obtain a silica-alumina gel with a solid content of 9% by weight. Add 10.8 g of cerium chloride (CeCl3·6H2O) to the silica-alumina gel and stir for 1 hour to obtain a mixed gel.

[0154] (2) Add ammonia to the obtained mixed gel to adjust the pH of the gel to 10.8, and then age it at 60°C for 8 hours to obtain a stabilized mixed gel.

[0155] (3) The stabilized mixed gel, 120 g of kaolin and 286 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 2 hours to obtain a slurry; then the slurry is spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers.

[0156] (4) The catalyst microspheres, ammonium sulfate and water were mixed in a mass ratio of 1:0.2:10 to carry out ammonium ion exchange. The mixture was stirred at 80°C for 30 minutes, filtered and repeated once.

[0157] (5) The ammonium-exchanged catalyst microspheres, deionized water, and 30.8 g of magnesium nitrate (MgSO4·7H2O) were mixed and stirred at room temperature for 30 minutes at a mass ratio of 1:0.01:6 for catalyst microspheres:MgO:water to load magnesium ions onto the catalyst microspheres. Measurements showed that the aqueous phase contained almost no magnesium ions. The mixture was then filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 450°C for 2 hours to obtain the catalytic cracking catalyst C2. Analysis showed that magnesium was mainly loaded on the surface of the catalyst microspheres, while cerium was uniformly distributed within the catalyst microspheres.

[0158] The composition and properties of the catalytic cracking catalyst C2 prepared in this embodiment are shown in Table 1.

[0159] Example 3

[0160] (1) Add 385 g of pseudoboehmite to 500 g of deionized water and mix well. Then add nitric acid to the mixture to adjust the pH of the slurry to 3.5. Add 250 g of alkaline silica sol and stir for 3 hours to obtain a silica-alumina gel with a solid content of 28% by weight. Add 51.6 g of zirconium nitrate (Zr(NO3)4·5H2O) to the silica-alumina gel and stir for 1 hour. Then add the mixed gel to the mixture.

[0161] (2) Add ammonia to the obtained mixed gel to adjust the pH of the gel to 11.5, and after aging at 25°C for 5 hours, a stabilized mixed gel is obtained.

[0162] (3) The stabilized mixed gel, 63 g of kaolin and 286 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 2 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers.

[0163] (4) The catalyst microspheres, ammonium sulfate and water were mixed in a mass ratio of 1:0.15:10 to carry out ammonium ion exchange. The mixture was stirred at 65°C for 30 minutes, filtered and repeated once.

[0164] (5) The ammonium-exchanged catalyst microspheres, deionized water, and 18.6 g of diammonium hydrogen phosphate were mixed and stirred for 30 minutes at a mass ratio of 1:0.02:5 (catalyst microspheres:P2O5:water) to load phosphorus onto the catalyst microspheres. Analysis showed that the aqueous phase contained almost no phosphorus. The mixture was then filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 550°C for 1 hour to obtain the catalytic cracking catalyst C3. Analysis showed that phosphorus was mainly loaded on the surface of the catalyst microspheres, while zirconium was uniformly distributed within the catalyst microspheres.

[0165] The composition and properties of the catalytic cracking catalyst C3 prepared in this embodiment are shown in Table 1.

[0166] Example 4

[0167] (1) Add 4507 g of aluminum sulfate solution to 200 g of deionized water and mix well. Then add oxalic acid to the mixture to adjust the pH of the slurry to 3. Add 133 g of alkaline silica sol and stir for 3 hours to obtain a silica-alumina gel with a solid content of 8% by weight. Add 17.2 g of zirconium nitrate (Zr(NO3)4·5H2O) to the silica-alumina gel and stir for 1.5 hours to obtain a mixed gel.

[0168] (2) Add ammonia to the obtained mixed gel to adjust the pH of the gel to 11, and age it at 25°C for 4 hours to obtain a stabilized mixed gel.

[0169] (3) The stabilized mixed gel, 70 g of kaolin and 143 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 2 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers.

[0170] (4) The catalyst microspheres, ammonium sulfate and water were mixed in a mass ratio of 1:0.05:10 to carry out ammonium ion exchange. The mixture was stirred at 65°C for 30 minutes, filtered and repeated three times.

[0171] (5) The ammonium-exchanged catalyst microspheres, deionized water, and 55.8 g of diammonium hydrogen phosphate were mixed and stirred for 30 minutes at a mass ratio of 1:0.06:5 (catalyst microspheres:P2O5:water) to load phosphate anions onto the catalyst microspheres. Analysis showed that almost no phosphorus was present in the aqueous phase. The mixture was filtered, and the resulting filter cake was dried at 120°C for 12 hours and calcined at 550°C for 1 hour to obtain the catalytic cracking catalyst C4. Analysis showed that phosphorus was mainly loaded on the surface of the catalyst microspheres, while zirconium was uniformly distributed within the catalyst microspheres.

[0172] The composition and properties of the catalytic cracking catalyst C4 prepared in this embodiment are shown in Table 1.

[0173] Example 5

[0174] (1) Add 701 g of aluminum isopropoxide to 500 g of deionized water and mix well. Then add acetic acid to the mixture to adjust the pH of the slurry to 3. Add 400 g of water glass solution and stir for 2 hours to obtain a silica-alumina gel with a solid content of 16% by weight. Add 34.0 g of yttrium nitrate (Y(NO3)3·6H2O) to the silica-alumina gel and stir for 1.5 hours to obtain a mixed gel.

[0175] (2) Add ammonia to the obtained mixed gel to adjust the pH of the gel to 11.5, and then age it at 60°C for 6 hours to obtain a stabilized mixed gel.

[0176] (3) The stabilized mixed gel, 76 g of kaolin and 429 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) were mixed and stirred for 2 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers.

[0177] (4) The catalyst microspheres, ammonium sulfate and water were mixed in a mass ratio of 1:0.05:10 to carry out ammonium ion exchange. The mixture was stirred at 65°C for 30 minutes, filtered and repeated twice.

[0178] (5) The ammonium-exchanged catalyst microspheres, deionized water, 61.5 g of magnesium sulfate, and 27.9 g of diammonium hydrogen phosphate were mixed and stirred for 60 minutes at a mass ratio of 1:0.02:0.03:5 for catalyst microspheres:MgO:P2O5:water to load magnesium ions and hydrogen phosphate ions onto the catalyst microspheres. Analysis showed that the aqueous phase contained almost no magnesium ions and phosphorus. The mixture was then filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 500°C for 2 hours to obtain the catalytic cracking catalyst C5. Analysis showed that phosphorus and magnesium were mainly loaded on the surface of the catalyst microspheres, while yttrium was uniformly distributed within the catalyst microspheres.

[0179] The composition and properties of the catalytic cracking catalyst C5 prepared in this embodiment are shown in Table 1.

[0180] Example 6

[0181] (1) Add 705 g of aluminum sol to 200 g of deionized water and mix well. Then add hydrochloric acid to the mixture to adjust the pH of the slurry to 3. Add 750 g of water glass solution and stir for 2 hours to obtain a silica-alumina gel with a solid content of 18% by weight. Add 5.4 g of lanthanum chloride (LaCl3·6H2O) to the silica-alumina gel and stir for 0.5 hours to obtain a mixed gel.

[0182] (2) Add ammonia to the obtained mixed gel to adjust the pH of the gel to 9, and age it at 80°C for 6 hours to obtain a stabilized mixed gel.

[0183] (3) The stabilized mixed gel, 209 g of kaolin and 71 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 2 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers.

[0184] (4) The catalyst microspheres, ammonium sulfate and water were mixed in a mass ratio of 1:0.1:10 to carry out ammonium ion exchange. The mixture was stirred at 60°C for 30 minutes, filtered and repeated twice.

[0185] (5) The ammonium-exchanged catalyst microspheres, deionized water, and 9.3 g of magnesium nitrate were mixed and stirred for 30 minutes at a mass ratio of 1:0.005:5 (catalyst microspheres:MgO:water) to load magnesium ions onto the catalyst microspheres. Analysis showed that the aqueous phase contained almost no magnesium ions. The mixture was then filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 500°C for 2 hours to obtain the catalytic cracking catalyst C6. Analysis showed that magnesium was mainly loaded on the surface of the catalyst microspheres, while lanthanum was uniformly distributed within the catalyst microspheres.

[0186] The composition and properties of the catalytic cracking catalyst C6 prepared in this embodiment are shown in Table 1.

[0187] Example 7

[0188] This embodiment prepares the catalytic cracking catalyst according to the operation method of Example 1, but with the following differences:

[0189] In step (1), 21.7 g of lanthanum chloride (LaCl3·6H2O) was replaced with 53.5 g of titanium tetrachloride;

[0190] In step (3), the amount of kaolin used is 85 grams.

[0191] The final catalytic cracking catalyst C7 was prepared.

[0192] Analysis revealed that magnesium was primarily loaded onto the surface of the catalyst microspheres, while lanthanum was uniformly distributed within the microspheres.

[0193] The composition and properties of the catalytic cracking catalyst C7 prepared in this embodiment are shown in Table 1.

[0194] Example 8

[0195] This embodiment prepares the catalytic cracking catalyst according to the operation method of Example 1, but the difference is that kaolin is added in step (1), as follows:

[0196] (1) Add 909 g of aluminum sol and 101 g of kaolin to 200 g of deionized water and mix evenly. Then add hydrochloric acid to the mixture to adjust the pH of the slurry to 3. Add 500 g of water glass solution and stir for 2 hours to obtain a mixed gel with a solid content of 22.2% by weight. Add 21.7 g of lanthanum chloride (LaCl3·6H2O) to the mixed gel and stir for 0.5 hours to obtain a mixed gel.

[0197] (2) Add ammonia to the obtained mixed gel to adjust the pH of the gel to 11, and after aging at 80°C for 6 hours, a stable mixed gel is obtained.

[0198] (3) The stabilized mixed gel and 286 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) were mixed for 2 hours under stirring to obtain a slurry. The slurry was then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers.

[0199] The final catalytic cracking catalyst C8 was obtained.

[0200] Analysis revealed that magnesium was primarily loaded onto the surface of the catalyst microspheres, while lanthanum was uniformly distributed within the microspheres.

[0201] The composition and properties of the catalytic cracking catalyst C8 obtained in Example 8 are shown in Table 1.

[0202] Comparative Example 1

[0203] The comparative example prepared the catalytic cracking catalyst according to the operation method of Example 1, but with the difference that: in step (1), the stabilizing element source lanthanum chloride (LaCl3·6H2O) was not added, and in step (3), the amount of kaolin was increased to 114 grams.

[0204] The final comparative catalytic cracking catalyst DC1 was obtained.

[0205] [Correction based on Rule 91 08.12.2025] Analysis showed that magnesium was mainly loaded on the surface of the catalyst microspheres.

[0206] The composition and properties of the catalytic cracking catalyst DC1 obtained in this comparative example are shown in Table 1.

[0207] The pore distribution of the obtained comparative catalytic cracking catalyst DC1 is shown in Figure 2.

[0208] Comparative Example 2

[0209] The comparative example prepared a catalytic cracking catalyst according to the operation method of Example 1, but with the difference that no activity-regulating element was loaded in step (5); that is, in step (5), the filter cake obtained in step (4) was directly dried at 120°C for 12 hours and calcined at 500°C for 2 hours. Finally, the comparative catalytic cracking catalyst DC2 was obtained.

[0210] Analysis revealed that magnesium was not loaded on the surface of the catalyst microspheres or in the pores of the surface layer, while lanthanum was uniformly distributed within the catalyst microspheres.

[0211] The composition and properties of the obtained comparative catalytic cracking catalyst DC2 are shown in Table 1.

[0212] Comparative Example 3

[0213] The catalytic cracking catalyst DC3 was prepared according to the method of Example 1 in CN117696043A.

[0214] Comparative Example 4

[0215] The comparative example prepared a catalytic cracking catalyst according to the operation method of Example 1, but the difference was that the stabilizing element source (21.7 g lanthanum chloride (LaCl3·6H2O)) and the activity regulating element source (37.1 g magnesium nitrate) were added in step (1), while the activity regulating element was not loaded in step (5).

[0216] The final comparative catalytic cracking catalyst DC4 was obtained. Analysis showed that magnesium and lanthanum were present almost uniformly in the obtained catalyst microspheres.

[0217] The composition and properties of the obtained comparative catalytic cracking catalyst DC4 are shown in Table 1.

[0218] Comparative Example 5

[0219] The comparative example prepared the catalytic cracking catalyst according to the operation method of Example 1, but with the difference that: no stabilizing element source was added in step (1), and instead, both the stabilizing element source and the activity regulating element source were loaded in step (5); that is, step (5) was performed as follows:

[0220] Step (5): The catalyst microspheres that have undergone ammonium ion exchange, deionized water, 37.1 g of magnesium nitrate and 21.7 g of lanthanum chloride were mixed and stirred for 30 minutes according to the mass ratio of catalyst microspheres:MgO:La2O3:water of 1:0.02:0.02:5. Magnesium and lanthanum elements were loaded on the catalyst microspheres and filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 500°C for 2 hours.

[0221] The final comparative catalytic cracking catalyst DC5 was obtained. Analysis showed that magnesium and lanthanum elements were mainly supported on the surface of the obtained catalyst microspheres.

[0222] The composition and properties of the comparative catalytic cracking catalyst DC5 obtained in this comparative example are shown in Table 1.

[0223] Comparative Example 6

[0224] This comparative example prepared a catalytic cracking catalyst according to the procedure of Example 1, but with the difference that the amounts of alumina sol and water glass solution added in step (1) were changed so that the SiO2 / Al2O3 molar ratio was approximately 3.4. That is, step (1) was performed as follows:

[0225] Step (1): Add 455g of aluminum sol to 200g of deionized water and mix evenly. Then add hydrochloric acid to the mixture to adjust the pH of the slurry to 3. Add 1000g of water glass solution and stir for 2 hours to obtain a silica-alumina gel with a solid content of 18.6% by weight. Add 21.7g of lanthanum chloride (LaCl3·6H2O) to the silica-alumina gel and stir for 0.5 hours to obtain a mixed gel.

[0226] The final comparative catalytic cracking catalyst DC6 was obtained. Analysis showed that magnesium was mainly supported on the surface of the catalyst microspheres and in the pores of the surface layer, while lanthanum was uniformly distributed in the catalyst microspheres.

[0227] Table 1. Composition and properties of catalytic cracking catalysts

[0228] Table 1 (continued)

[0229] As can be seen from the results in Table 1, due to the SiO2 / Al2O3 molar ratio of less than 2 in the matrix of the first series of catalytic cracking catalysts according to the present invention, and the inclusion of stabilizing elements in the matrix and activity regulating elements on the surface and surface layer of the catalyst microspheres, the first series of catalytic cracking catalysts according to the present invention exhibits significantly higher 10-100 nm pore distribution, higher microreactor activity, and excellent wear resistance compared to comparative catalytic cracking catalysts. In particular, as determined by the low-temperature nitrogen adsorption method, the total pore volume of the catalytic cracking catalyst is not less than 0.5 mL / g, wherein the pore volume of pores with a diameter of 10-100 nm accounts for more than 80% of the total pore volume, and the most probable pore diameter is 10-40 nm, which gives it a higher capacity to contain heavy metals, and the microreactor activity is not less than 50 after treatment at 800°C and 100% water vapor for 17 hours.

[0230] Furthermore, a comparison of the experimental results of Example 1 with those of Comparative Examples 4 and 5 shows that the specific distribution of stabilizing elements and activity regulating elements in the catalytic cracking catalyst microspheres of the present invention is beneficial to further improving the strength, total pore volume, pore distribution more suitable for catalytic cracking reaction, and catalytic activity stability of the catalyst.

[0231] Test case

[0232] The catalysts obtained in the above examples and comparative examples were pre-aged in a fixed-bed aging apparatus at 800°C with 100% steam for 12 hours, and then evaluated in an ACE apparatus. The properties of the reactant oil are shown in Table 2, the reaction temperature is 520°C, the catalyst-to-oil weight ratio is 4, and the test results of the catalyst's catalytic performance are shown in Table 3.

[0233] Conversion rate (%) = Gasoline yield (%) + Liquefied petroleum gas yield (%) + Dry gas yield (%) + Coke yield (%);

[0234] Coke selectivity (%) = Coke yield (%) / Conversion rate (%) × 100%.

[0235] Table 2. Properties of crude oil

[0236] Table 3. Catalytic performance of catalysts

[0237] Table 3 (continued)

[0238] The test results of the catalytic performance in Table 3 show that, compared with the comparative catalytic cracking composition, the catalytic cracking catalyst according to the present invention has superior heavy oil cracking ability and resistance to metal contamination. When the catalytic cracking catalyst according to the present invention is applied to the heavy oil catalytic cracking reaction, the catalytic cracking catalyst according to the present invention has higher conversion rate, lower heavy oil (slurry) yield, higher light oil yield, and significantly lower coke yield and selectivity.

[0239] Examples 9-15 and Comparative Examples 8-12 below are used to illustrate the preparation and properties of the second series of catalytic cracking catalysts according to the present invention.

[0240] Example 9

[0241] (1) Add 909 g of aluminum sol to 200 g of deionized water and mix evenly. Then add hydrochloric acid to the mixture to adjust the pH of the slurry to 3. Add 500 g of water glass solution and stir for 2 hours. Then add 10 g of magnesium oxide and stir for 1 hour to obtain a silica-alumina-magnesium gel with a solid content of 19% by weight.

[0242] (2) Ammonia was added to the obtained silica-alumina-magnesium gel to adjust the pH of the gel to 11.5. After aging at room temperature for 3 hours, a stabilized silica-alumina-magnesium mixed gel was obtained.

[0243] (3) The stabilized silicon-aluminum-magnesium mixed gel, 70 g of kaolin and 343 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 2 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers. The tail gas temperature of the spray drying is 160°C, and the microsphere is calcined at 300°C for 1 hour.

[0244] (4) The catalyst microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.08:10 for ammonium ion exchange. The mixture was stirred at 60°C for 30 minutes, filtered, and repeated twice until the sodium oxide content was <0.3% by weight.

[0245] (5) The catalyst microspheres that have undergone ammonium ion exchange, deionized water and 27.9 g of diammonium hydrogen phosphate were mixed according to the mass ratio of catalyst microspheres:P2O5:water of 1:0.03:4. The mixture was stirred at 60°C for 30 minutes to load phosphorus onto the catalyst microspheres. It was found that there was essentially no phosphorus in the aqueous phase. The mixture was filtered to load phosphorus onto the surface of the catalyst microspheres and possibly into the pores of the surface layer. The resulting filter cake was dried at 120°C for 12 hours and calcined at 500°C for 2 hours to obtain the catalytic cracking catalyst C9 (the composition and properties of which are shown in Table 4).

[0246] Analysis revealed that magnesium was uniformly distributed within the catalyst microspheres, while phosphorus was primarily loaded onto the surface of the catalyst microspheres.

[0247] The pore distribution of the catalytic cracking catalyst C9 prepared in this embodiment is shown in Figure 3.

[0248] Example 10

[0249] (1) Add 2606 g of aluminum sulfate solution to 200 g of deionized water and mix well. Then add sulfuric acid to the mixture to adjust the pH of the slurry to 3. Then add 663 g of water glass solution and stir for 2 hours. Then add 40.2 g of magnesium acetate and stir for 0.5 hours to obtain a silica-alumina-magnesium mixed gel with a solid content of 9.3% by weight.

[0250] (2) Add ammonia to the obtained silicon-aluminum-magnesium mixed gel to adjust the pH of the gel to 11, and age it at room temperature for 8 hours to obtain a stabilized silicon-aluminum-magnesium mixed gel.

[0251] (3) The stabilized silicon-aluminum-magnesium mixed gel, 63 g of kaolin and 343 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 2 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers. The tail gas temperature of the spray drying is 190°C, and the microsphere is calcined at 300°C for 1 hour.

[0252] (4) The catalyst microspheres, ammonium sulfate and water are mixed in a mass ratio of 1:0.2:10 to carry out ammonium ion exchange. The mixture is stirred at 80°C for 30 minutes, filtered, and repeated once until the sodium oxide content is <0.3% by weight.

[0253] (5) 8.9 g of boric acid was dissolved in 300 g of deionized water to prepare an impregnation solution according to the mass ratio of catalyst microspheres:B2O3 of 1:0.01. The impregnation solution was then contacted with the catalyst microspheres that had undergone ammonium ion exchange and kept at room temperature for 12 hours to load boron onto the surface of the catalyst microspheres. It was found that there was basically no boric acid in the aqueous phase. The solution was filtered, dried at 100 °C for 12 hours, and calcined at 450 °C for 2 hours to obtain the catalytic cracking catalyst C10 (its composition and physical properties are shown in Table 4).

[0254] Analysis revealed that magnesium was uniformly distributed within the catalyst microspheres, while boron was mainly loaded on the surface of the catalyst microspheres and a small amount loaded in the pores of the surface layer.

[0255] Example 11

[0256] (1) Add 269 g of pseudoboehmite to 500 g of deionized water and mix evenly. Then add hydrochloric acid to the mixture to adjust the pH of the slurry to 2.5. Stir for 3 hours, then add 267 g of alkaline silica sol. After stirring for 1 hour, add 30.8 g of magnesium sulfate and stir for 2 hours to obtain a silica-alumina-magnesium gel with a solid content of 22% by weight.

[0257] (2) Add ammonia to the obtained silica-alumina-magnesium gel to adjust the pH of the gel to 10, and age it at 80°C for 1 hour to obtain a stabilized silica-alumina-magnesium mixed gel.

[0258] (3) The stabilized silicon-aluminum-magnesium mixed gel, 133 g of kaolin and 343 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 2 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers after calcining at 300°C for 2 hours.

[0259] (4) The catalyst microspheres, ammonium sulfate and water are mixed in a mass ratio of 1:0.15:10 to carry out ammonium ion exchange. The mixture is stirred at 65°C for 30 minutes, filtered, and repeated once until the sodium oxide content is <0.3% by weight.

[0260] (5) The catalyst microspheres that have undergone ammonium ion exchange, deionized water, and 21.7 g of lanthanum chloride (LaCl3·6H2O) were stirred at 60 °C for 30 minutes according to a mass ratio of catalyst microspheres:La2O3:water of 1:0.02:5. It was found that there were basically no lanthanum ions in the aqueous phase. The mixture was then filtered. Then, 9.3 g of diammonium hydrogen phosphate was dissolved in 200 g of deionized water according to a mass ratio of catalyst microspheres:P2O5 of 1:0.01 to prepare an impregnation solution. The impregnation solution was contacted with the catalyst microspheres loaded with lanthanum as described above. After being kept at room temperature for 12 hours, it was found that there were basically no phosphorus elements in the aqueous phase. The mixture was then filtered, dried at 120 °C, and calcined at 550 °C for 2 hours to obtain the catalytic cracking catalyst C11 (its composition and properties are shown in Table 4).

[0261] Analysis revealed that magnesium was uniformly distributed within the catalyst microspheres, while lanthanum and phosphorus were primarily loaded onto the surface of the microspheres and into the pores of the surface layer.

[0262] Example 12

[0263] (1) Add 4648g of aluminum sol to 200g of deionized water and mix evenly. Then add hydrochloric acid to the mixture to adjust the pH of the slurry to 3. Add 133g of alkaline silica sol and stir for 2 hours. Then add 61.5g of magnesium sulfate and stir for 2 hours to obtain a silica-alumina-magnesium gel with a solid content of 7% by weight.

[0264] (2) Add ammonia to the obtained silica-alumina-magnesium gel to adjust the pH of the gel to 11, and age it at 40°C for 6 hours to obtain a stabilized silica-alumina-magnesium mixed gel.

[0265] (3) The stabilized silicon-aluminum-magnesium mixed gel, 63 g of kaolin and 143 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) were mixed and stirred for 2.5 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers after calcining at 450°C for 2 hours.

[0266] (4) The catalyst microspheres, ammonium sulfate and water were mixed in a mass ratio of 1:0.05:10 to carry out ammonium ion exchange. The mixture was stirred at 65°C for 30 minutes, filtered, and repeated three times until the sodium oxide content was <0.3% by weight.

[0267] (5) The catalyst microspheres that have undergone ammonium ion exchange, deionized water, 27.9 g of diammonium hydrogen phosphate and 10.8 g of cerium chloride (CeCl3·7H2O) were mixed according to the mass ratio of catalyst microspheres:P2O5:CeO2:water of 1:0.03:0.01:6 and stirred at 60°C for 60 minutes. It was found that there were basically no cerium ions and hydrogen phosphate ions in the aqueous phase. The mixture was filtered. The filter cake was dried at 120°C for 12 hours and calcined at 550°C for 1 hour to obtain the catalytic cracking catalyst C12 (its composition and properties are shown in Table 4).

[0268] Analysis revealed that magnesium was uniformly distributed within the catalyst microspheres, while cerium and phosphorus were primarily loaded onto the surface of the microspheres and into the pores of the surface layer.

[0269] Example 13

[0270] (1) Add 861 g of aluminum isopropoxide to 500 g of deionized water and mix evenly. Then add acetic acid to the mixture to adjust the pH of the slurry to 2. Stir for 4 hours, then add 300 g of water glass solution and stir for 1 hour. Then add 55.6 g of magnesium nitrate and stir for 1 hour to obtain a silica-alumina-magnesium gel with a solid content of 17% by weight.

[0271] (2) Ammonia was added to the obtained silica-alumina-magnesium gel to adjust the pH of the gel to 9.6. After aging at 60°C for 6 hours, a stabilized silica-alumina-magnesium mixed gel was obtained.

[0272] (3) The stabilized silicon-aluminum-magnesium mixed gel, 63 g of kaolin and 371 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 3 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers. The tail gas temperature of the spray drying is 180°C, and the microsphere is calcined at 350°C for 1 hour.

[0273] (4) The catalyst microspheres, ammonium sulfate and water are mixed in a mass ratio of 1:0.05:10 to carry out ammonium ion exchange. The mixture is stirred at 65°C for 30 minutes, filtered, and repeated once until the sodium oxide content is <0.3% by weight.

[0274] (5) The ammonium-exchanged catalyst microspheres, deionized water, and 41.4 g of phosphoric acid were mixed at a mass ratio of 1:0.06:8 (catalyst microspheres:P2O5:water) and stirred at 60°C for 40 minutes. The mixture was found to contain virtually no phosphorus in the aqueous phase. The mixture was then filtered. The resulting filter cake was dried at 120°C for 12 hours and then calcined at 400°C for 2 hours to obtain the catalytic cracking catalyst C13 (its composition and properties are shown in Table 4). Analysis showed that magnesium was uniformly distributed within the catalyst microspheres, while phosphorus was mainly loaded onto the surface of the catalyst microspheres.

[0275] Example 14

[0276] (1) Add 705 g of aluminum sol to 300 g of deionized water and mix evenly. Then add nitric acid to the mixture to adjust the pH of the slurry to 3. Add 750 g of water glass solution and stir for 3 hours. Then add 15.4 g of magnesium sulfate and stir for 1 hour to obtain a silica-alumina-magnesium gel with a solid content of 17.4% by weight.

[0277] (2) Add ammonia to the obtained silica-alumina-magnesium gel to adjust the pH of the gel to 9, and age it at 60°C for 6 hours to obtain a stabilized silica-alumina-magnesium mixed gel.

[0278] (3) The stabilized silicon-aluminum-magnesium mixed gel, 207 g of kaolin and 71 g of REUSY molecular sieve slurry (the solid content of the molecular sieve slurry is 35% by weight) are mixed and stirred for 2 hours, and then spray-dried to form a catalyst microsphere with an average particle size of about 75 micrometers. The tail gas temperature of the spray drying is 170°C, and the microsphere is calcined at 400°C for 1 hour.

[0279] (4) The catalyst microspheres, ammonium sulfate and water were mixed in a mass ratio of 1:0.1:10 to carry out ammonium ion exchange. The mixture was stirred at 60°C for 30 minutes, filtered, and repeated twice until the sodium oxide content was <0.3% by weight.

[0280] (5) The ammonium-exchanged catalyst microspheres, deionized water, and 7.4 g of diammonium hydrogen phosphate were mixed at a mass ratio of 1:0.005:5 (catalyst microspheres:P2O5:water) and stirred at 60°C for 30 minutes. The mixture was found to contain virtually no phosphorus in the aqueous phase. The mixture was then filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 500°C for 2 hours to obtain the catalytic cracking catalyst C14 (its composition and properties are shown in Table 4). Analysis showed that magnesium was uniformly distributed within the catalyst microspheres, while phosphorus was mainly loaded onto the surface of the catalyst microspheres.

[0281] Example 15

[0282] The catalytic cracking catalyst was prepared according to the method described in Example 9, except that in step (5), 27.9 g of diammonium hydrogen phosphate was replaced with 50.9 g of Y(NO3)3·6H2O, so that the mass ratio of catalyst microspheres:Y2O3:water was 1:0.03:4.

[0283] The final catalytic cracking catalyst C15 was obtained (its composition and properties are shown in Table 4). Analysis showed that magnesium was uniformly distributed in the catalyst microspheres, while yttrium was mainly supported on the surface of the catalyst microspheres.

[0284] [Corrected according to Rule 91, 08.12.2025] Comparative Example 7

[0285] [Correction 08.12.2025 according to Rule 91] This comparative example prepared a catalytic cracking catalyst according to the method described in Example 9, except that magnesium oxide (a source of stabilizing elements) was not added in step (1); the catalytic cracking catalyst DC7 was obtained (its composition and properties are shown in Table 4).

[0286] [Correction based on Rule 91, 08.12.2025] The pore distribution of the catalytic cracking catalyst DC7 prepared by this comparative example is shown in Figure 3. Analysis revealed that the catalyst matrix does not contain magnesium, while phosphorus is primarily supported on the surface of the catalyst microspheres.

[0287] Comparative Example 9

[0288] The comparative example prepared a catalytic cracking catalyst according to the method described in Example 9, but the difference was that no activity-regulating element was loaded in step (5).

[0289] The final catalytic cracking catalyst DC9 was obtained (its composition and properties are shown in Table 4). Analysis showed that magnesium was uniformly distributed in the catalyst microspheres, while no activity-regulating elements were loaded on the surface of the catalyst microspheres.

[0290] Comparative Example 10

[0291] The comparative example prepared the catalytic cracking catalyst DC10 according to the method of Example 1 in CN117696043A.

[0292] Comparative Example 11

[0293] The comparative example prepared a catalytic cracking catalyst according to the operation method of Example 10, but the difference was that the activity regulating element source boric acid was added together with the stability element source magnesium acetate in step (1) instead of in step (5).

[0294] A catalytic cracking catalyst, DC11, was obtained. Analysis showed that magnesium and boron were uniformly present in the obtained catalyst microspheres.

[0295] The composition and properties of the catalytic cracking catalyst DC11 obtained in this comparative example are shown in Table 4.

[0296] Comparative Example 12

[0297] This comparative example prepared a catalytic cracking catalyst according to the operation method of Example 10, but with the difference that the amounts of aluminum sol and water glass solution added in step (1) were changed so that the SiO2 / Al2O3 molar ratio of the catalyst matrix was about 5.7. That is, in step (1): 1300g of aluminum sulfate solution was added to 200g of deionized water and mixed evenly, then sulfuric acid was added to the resulting mixture to adjust the pH of the slurry to 3, and then 1108g of water glass solution was added. After stirring for 2 hours, 40.2g of magnesium acetate was added and stirred for 0.5 hours to obtain a silicon-aluminum-magnesium mixed gel with a solid content of 9.3% by weight.

[0298] The final catalytic cracking catalyst DC12 was obtained. Analysis showed that magnesium was uniformly distributed in the catalyst microspheres, while boron was mainly supported on the surface of the catalyst microspheres and a small amount was supported in the pores of the surface layer.

[0299] The composition and properties of the catalytic cracking catalyst DC12 obtained in this comparative example are shown in Table 4.

[0300] Table 4. Composition and properties of catalytic cracking catalysts

[0301] Table 4 (continued)

[0302] As can be seen from the results in Table 4, compared with the comparative catalytic cracking catalyst, the second series of catalytic cracking catalysts according to the present invention have a significantly larger total pore volume and a significantly higher 10-100 nm pore distribution (expressed as the ratio of 10-100 nm pore volume to total pore volume, reaching more than 80% of the total pore volume), due to the matrix having a SiO2 / Al2O3 molar ratio of less than 2, and the inclusion of the stabilizing element Mg in the matrix and the activity regulating element substantially supported on the surface of the microspheres. This results in a higher capacity to accommodate heavy metals, while maintaining good wear resistance, higher alkali center content, and excellent activity stability; its microreactor activity after treatment at 800°C and 100% water vapor for 17 hours is higher than 60.

[0303] Furthermore, by comparing the experimental results of Example 10 and Comparative Example 11, it can be seen that the specific distribution of stabilizing elements and activity regulating elements in the catalytic cracking catalyst microspheres of the present invention is more conducive to obtaining a large total pore volume, a pore distribution more suitable for catalytic cracking reaction, and high activity stability in the catalytic cracking catalyst of the present invention.

[0304] Test case

[0305] The catalysts prepared in the embodiments of the present invention and the catalysts prepared in the comparative examples were pre-aged in a fixed-bed aging apparatus at 800°C and 100% steam for 17 hours, and then evaluated in an ACE apparatus. The properties of the feedstock oil are shown in Table 5, the reaction temperature was 525°C, the catalyst-to-oil weight ratio was 6, and the test results of the catalytic performance of the catalytic cracking catalysts are shown in Table 6.

[0306] Conversion rate (%) = Gasoline yield (%) + Liquefied petroleum gas yield (%) + Dry gas yield (%) + Coke yield (%);

[0307] Coke selectivity (%) = Coke yield (%) / Conversion rate (%) × 100%.

[0308] Table 5. Properties of Crude Oil

[0309] Table 6. Catalytic performance of catalytic cracking catalysts

[0310] Table 6 (continued)

[0311] As can be seen from the test results of the catalytic performance in Table 6, when the catalytic cracking catalyst according to the present invention is applied to the heavy oil catalytic cracking reaction, the yield of light oil is significantly higher, the slurry oil yield is significantly lower, the ratio of diesel yield to slurry oil yield is significantly higher, and the yield and selectivity of coke are significantly lower, thus exhibiting superior catalytic effect.

[0312] The above embodiments describe the preferred embodiments of the present invention in detail. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0313] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0314] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A catalytic cracking catalyst, characterized in that, Based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 5-40 wt% molecular sieve, 5-40 wt% clay on a dry basis, 5-35 wt% silicon species (SiO2), 30-75 wt% aluminum species (Al2O3), 0.5-15 wt% stabilizing elements (oxides), and 0.5-10 wt% activity-regulating elements (oxides); the content ratio of silicon species and aluminum species, based on the SiO2 / Al2O3 molar ratio, is 0.05-2; wherein the stabilizing element is selected from at least one of Group IIIB and Group IVB elements, and the activity-regulating element is selected from at least one of Mg and P; or, the stabilizing element is selected from Mg, and the activity-regulating element is selected from at least one of P, B, Fe, Group IIIB, and Group IVB elements.

2. The catalytic cracking catalyst according to claim 1, characterized in that, Based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 10-35 wt% molecular sieve, 10-35 wt% clay on a dry basis, 6-30 wt% silicon species (SiO2), 41-70 wt% aluminum species (Al2O3), 0.5-5 wt% stabilizing elements (oxides), and 1-8 wt% activity-regulating elements (oxides), wherein the content ratio of silicon species to aluminum species (SiO2 / Al2O3 molar ratio) is 0.2-1.5; wherein the stabilizing element is selected from at least one of Group IIIB and Group IVB elements, and the activity-regulating element is selected from at least one of Mg and P; or, Based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 10-35 wt% molecular sieve, 10-35 wt% clay on a dry basis, 6-30 wt% silicon species (SiO2), 35-70 wt% aluminum species (Al2O3), 1-10 wt% stabilizing elements (oxides), and 1-8 wt% activity-regulating elements (oxides), wherein the content ratio of silicon species to aluminum species (SiO2 / Al2O3 molar ratio) is 0.2-1.5; wherein the stabilizing element is selected from Mg, and the activity-regulating element is selected from at least one of P, B, Fe, Group IIIB elements, and Group IVB elements. Preferably, the total amount of the silicon species, calculated as SiO2, and the aluminum species, calculated as Al2O3, is 45-90% by weight, more preferably 50-80% by weight.

3. The catalytic cracking catalyst according to claim 1 or 2, characterized in that, The catalytic cracking catalyst exists in the form of microspheres, with the stabilizing element distributed inside the catalyst microspheres and the activity regulating element mainly loaded on the surface of the catalyst microspheres and optionally loaded in small amounts in the pores of the surface layer with a very thin thickness.

4. The catalytic cracking catalyst according to any one of claims 1-3, characterized in that, The micro-reaction activity of the catalytic cracking catalyst after treatment at 800°C and 100% steam for 17 hours is not less than 50, preferably not less than 60.

5. The catalytic cracking catalyst according to any one of claims 1-4, characterized in that, The total pore volume of the catalyst, as determined by the low-temperature nitrogen adsorption method, is not less than 0.5 mL / g, preferably 0.6-1.5 mL / g, and the pore volume of pores with a diameter of 10-100 nm accounts for more than 80% of the total pore volume, preferably 85%-99%. And / or, the most probable pore size of the catalyst is 10-40 nm, preferably 13-35 nm, more preferably 15-30 nm.

6. The catalytic cracking catalyst according to any one of claims 1-5, characterized in that, The molecular sieve is selected from at least one of Y zeolite, MFI type zeolite and β zeolite; preferably, the Y zeolite is selected from at least one of HY, REY, REHY, USY, REUSY and PRESY; And / or, the clay is selected from at least one of kaolin, bentonite, montmorillonite, sepiolite, diatomite, rettoite, attapulgite and halloysite, preferably kaolin; And / or, the stabilizing element is selected from at least one of La, Ce, Y, Zr and Ti, and the activity regulating element is selected from at least one of Mg and P; or the stabilizing element is selected from Mg, and the activity regulating element is selected from at least one of P, B, La, Ce, Y, Zr, Ti and Fe.

7. The catalytic cracking catalyst according to any one of claims 1-6, characterized in that, When the catalytic cracking catalyst contains Mg, the content of base centers in the catalyst, as determined by the CO2-TPD method, is 0.05-0.5 mmol / g, preferably 0.1-0.4 mmol / g.

8. A method for preparing a catalytic cracking catalyst according to any one of claims 1-7, characterized in that, The method includes the following steps: (1) A mixed gel is prepared by uniformly mixing a silicon source, an aluminum source, a stabilizing element source, and an optional acid in the presence of a solvent. (2) The obtained mixed gel is subjected to aging treatment to obtain a stabilized mixed gel; (3) The stabilized mixed gel, clay and molecular sieve obtained are mixed to obtain a slurry, which is then spray-dried and optionally calcined to obtain catalyst microspheres. (4) Allow the catalyst microspheres to undergo ammonium ion exchange, and then (5) Loading an activity-regulating element onto a catalyst microsphere that has undergone ammonium ion exchange; optionally, filtering, drying and calcining the catalyst microsphere loaded with the activity-regulating element; To obtain a catalytic cracking catalyst; The amount of the stabilizing element source, silicon source, aluminum source, clay, molecular sieve, and activity regulating element source added is such that, based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 5-40 wt% molecular sieve, 5-40 wt% clay on a dry basis, 5-35 wt% silicon species based on SiO2, 30-75 wt% aluminum species based on Al2O3, 0.5-15 wt%, preferably 0.5-5 wt% stabilizing element based on oxide, and 0.5-10 wt% activity regulating element based on oxide, and the content ratio of silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.05-2, preferably 0.2-1.

5.

9. The preparation method according to claim 8, characterized in that, In step (1), in the presence of a solvent, a silicon source, an aluminum source, and an acid are mixed to obtain a silicon-aluminum gel, and then a stabilizing element source is mixed with the silicon-aluminum gel to obtain a mixed gel; or, in the presence of a solvent, a silicon source, an aluminum source, a stabilizing element source, and an acid are directly mixed to obtain a mixed gel. The aluminum source is selected from at least one of aluminum sol, aluminum sulfate, aluminum isopropoxide, aluminum chloride, aluminum nitrate, boehmite, aluminum oxide, aluminum hydroxide, and sodium aluminate, preferably at least one of aluminum sulfate and aluminum sol. And / or, the silicon source is selected from at least one of water glass, alkaline silica sol, acidic silica sol, tetraethyl orthosilicate and tetramethoxysilane, preferably at least one of water glass and alkaline silica sol; And / or, the source of the stabilizing element is a compound containing a stabilizing element, preferably selected from at least one of nitrates, chlorides, sulfates, phosphates, acetates, oxalates, oxides and alkoxides of the stabilizing element, more preferably at least one of nitrates and chlorides.

10. The preparation method according to claim 9, characterized in that, The solid content of the silica-alumina gel is 5-40% by weight, preferably 5-35% by weight; And / or, the amount of acid used is such that the pH of the mixture obtained after mixing is 1-4; And / or, the acid is at least one of inorganic and organic acids, preferably selected from at least one of hydrochloric acid, sulfuric acid, nitric acid, acetic acid and citric acid.

11. The preparation method according to any one of claims 8-10, characterized in that, In step (2), before aging the mixed gel, the mixed gel is uniformly mixed with an alkali to obtain a mixture with a pH of 9-12; and / or, the aging conditions include: a temperature of 10-100°C, preferably 20-80°C; a time of 1-24 hours, preferably 4-20 hours; preferably, the alkali is selected from at least one of ammonia, sodium hydroxide, sodium carbonate, and sodium aluminate.

12. The preparation method according to any one of claims 8-11, characterized in that, In step (3), the tail gas temperature of the spray drying of the slurry is 100-300℃, preferably 120-200℃; and / or, the conditions for calcination include: a temperature of 300-600℃, a time of 0.5-5 hours, and a heating rate of 2-10℃ / minute; and / or, the average particle size of the obtained catalytic cracking catalyst microspheres is 60-90 micrometers, preferably 65-85 micrometers.

13. The preparation method according to any one of claims 8-12, characterized in that, In step (4), the ammonium ion exchange is performed as follows: the catalyst microspheres are contacted with an ammonium salt solution at a temperature of 20-100°C for 10-120 minutes, such that the sodium oxide content on the surface of the ammonium ion-exchanged catalyst microspheres is not higher than 0.3% by weight; wherein, on a dry basis, the mass ratio of the catalyst microspheres to the ammonium salt is 1:0.01-0.5, preferably 1:0.05-0.2; and / or, on a dry basis, the mass ratio of the catalytic cracking aid microspheres to the solvent is 1:2-20; Preferably, the ammonium salt used for the ammonium ion exchange is selected from at least one of ammonium chloride, ammonium sulfate, ammonium bisulfate, ammonium nitrate, ammonium carbonate, ammonium bicarbonate, ammonium oxalate, and ammonium phosphate, and more preferably from at least one of ammonium chloride, ammonium sulfate, and ammonium oxalate.

14. The preparation method according to any one of claims 8-13, characterized in that, In step (5), the activity regulating element is loaded by the following method: in the presence of a solvent, the activity regulating element source is mixed and contacted with the ammonium ion-exchanged catalyst microspheres for impregnation and / or ion exchange, wherein, on a dry basis, the mass ratio of the ammonium ion-exchanged catalyst microspheres to the activity regulating element source (based on oxides) is 1:0.005-0.1, preferably 1:0.01-0.08; wherein, the activity regulating element source is selected from soluble compounds containing activity regulating elements, preferably selected from at least one of nitrates, chlorides, sulfates, phosphates, acetates, oxalates, oxides, and alkoxides of activity regulating elements, for example, selected from... At least one of magnesium sulfate, magnesium nitrate, magnesium chloride, magnesium acetate, magnesium oxalate, orthophosphoric acid, phosphorous acid, ammonium phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, and pyrophosphoric acid, more preferably at least one of magnesium sulfate, magnesium nitrate, magnesium oxalate, ammonium dihydrogen phosphate, and diamine hydrogen phosphate; preferably, the conditions for contacting the active regulating element source with the ammonium ion-exchanged catalyst microspheres include: a temperature of 20-100°C and a time of 10-120 minutes; and / or, in step (5), the conditions for calcining the catalyst microspheres include: a temperature of 400-600°C, preferably 450-550°C, under flowing air; and a time of 0.5-3 hours, preferably 1-3 hours.

15. A method for catalytic cracking of heavy oil, characterized in that, The heavy oil is brought into contact with the catalytic cracking catalyst according to any one of claims 1-7 and subjected to a catalytic cracking reaction.

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