Catalytic cracking additive, preparation method therefor, catalytic cracking composition comprising the additive, and use thereof

Abstract

The present invention relates to a catalytic cracking additive. The catalytic cracking additive comprises: 5-50 wt% of a clay on a dry basis, 5-40 wt% of a silicon species calculated as SiO2, 30-80 wt% of an aluminum species calculated as Al2O3, 0.5-15 wt% of a stability element calculated as an oxide; and 0.5-10 wt% of an activity regulating element calculated as an oxide, and the content ratio of the silicon species to the aluminum species in terms of a SiO2 / Al2O3 molar ratio is 0.05-2, wherein the stability element is selected from Mg, and the activity regulating element is selected from at least one of P, B, a group IIIB element, and a group IVB element; or, the stability element is selected from at least one of a group IIIB element and a group IVB element, and the activity regulating element is selected from at least one of Mg and P. The present invention further relates to a method for preparing the catalytic cracking additive and a heavy oil catalytic cracking method using the catalytic cracking additive.

Description

Catalytic cracking additives, their preparation methods, catalytic cracking compositions containing the additives, and their uses. Technical Field

[0001] This invention relates to the field of refining catalysts, and more specifically to a highly stable catalytic cracking aid and its preparation method, a catalytic cracking composition comprising this catalytic cracking aid, and its uses. Background Technology

[0002] The oil refining industry is facing significant challenges, including scarce and degraded petroleum resources and the need for low-carbon emissions. Catalytic cracking, a key process, can convert heavy oil and residual oil into high-value products such as liquefied petroleum gas (LPG), gasoline, and diesel. These heavy feedstocks are characterized by large molecular size, high density, high carbon residue, and high heavy metal content, placing more stringent requirements on the catalysts and additives used in catalytic cracking. Catalytic cracking additives are the most flexible, rapid, and effective means to promote the deep conversion of heavy feedstocks, increase high-value-added products, and reduce coke yield. Catalyst and additive technologies for reducing coke yield have become a key research direction, currently mainly achieved through ultrastable Y-type molecular sieve technology and the preparation of catalyst support materials with good pore structure and acidity distribution. In terms of support materials, the preparation and synthesis of mesoporous and macroporous acidic materials based on silicon-aluminum are the main research hotspots. Especially in the development of heavy oil catalytic cracking additives, more attention is paid to adjusting and optimizing the matrix performance. By changing the acidity and pore structure of the matrix, the diffusion efficiency of reactants and products is enhanced, thereby more effectively promoting the cracking ability of heavy oil macromolecules.

[0003] US5045519A discloses a method for preparing a catalyst support containing aluminosilicates, which involves mixing an aluminum-containing compound and a silica compound, wherein the aluminum-containing compound is obtained by hydrolysis of a C2-C20 alcohol-based aluminum salt, and simultaneously or subsequently adding silica purified by an ion exchanger, followed by drying and calcination to obtain the catalyst. Based on this, WO9712011A1 discloses a bottom oil cracking aid (BCA) without molecular sieves, containing 5-30 wt% of the aluminosilicate compound prepared by US5045519A, 15-30 wt% of acidifiable alumina, 5-25 wt% of non-acidifiable alumina or a phosphorus-containing compound, 30-60 wt% of clay on a dry basis, and may also contain less than 5 wt% of inert silicon species and less than 2 wt% of a metal trapping agent. However, the aluminosilicate compound used in this aid has a high preparation cost.

[0004] CN102974337A discloses a catalytic cracking additive and its preparation method. This additive contains mesoporous silica-alumina material, a metal trapping agent, and clay and / or heat-resistant inorganic oxides. The mesoporous silica-alumina material preferably has a pseudo-boehmite crystal phase structure, with an oxide weight ratio of (0-0.2)Na₂O·(40-90)Al₂O₃·(10-60)SiO₂. When applied to heavy oil catalytic cracking, it exhibits strong heavy oil cracking capability, higher light oil yield, and better coke selectivity. However, there is still room for improvement in the hydrothermal stability and pore structure of this additive.

[0005] CN102949986A provides a mesoporous acidic silica-alumina catalytic material with a pseudo-boehmite crystal phase structure, a pore volume of 1.0-2.0 ml / g, and an average pore diameter of 8-20 nm. The ratio of pyridine Brønsted acid to Lewis acid measured at 200 °C is 0.060-0.085.

[0006] CN108786782A discloses a catalytic cracking aid for reducing coke yield and its preparation method. This catalytic cracking aid, based on a catalyst mass composition of 100 parts, comprises 5-25 parts of rare earth-containing macroporous silica-alumina material, 15-42 parts of alumina material, 1-10 parts of heavy metal scavenger, and 30-60 parts of clay. The rare earth-containing macroporous silica-alumina material, based on oxide weight, has the following anhydrous chemical formula: (0-0.3)Na₂O:(2-16)Al₂O₃:(75-92)SiO₂:(2-10)RE₂O₃; its pore volume is 0.8-2 mL / g, and its specific surface area is 150-350 m² / g. 2 With a most probable pore size of 30-100 nm and a B / L acid ratio of 0.6-1.9, this additive exhibits good reactivity in improving the coke selectivity of the catalyst. However, this catalytic cracking additive introduces a significant amount of clay, which can cause blockage of the existing mesoporous and macroporous structures.

[0007] However, existing heavy oil catalytic cracking additives generally use boehmite and mesoporous silica-alumina materials as the main active matrix, matched with appropriate amounts of binders and clay components. However, during the additive preparation process, due to the poor adhesion of mesoporous silica-alumina materials, a large amount of binder components are required, which inevitably causes blockage of the original mesoporous structure. In addition, existing catalytic cracking support materials such as boehmite and mesoporous silica-alumina materials have problems such as small pore volume, low pore size, small B / L acid ratio, and poor hydrothermal stability. Moreover, the coke selectivity and heavy oil conversion capacity are still difficult to achieve the ideal state.

[0008] Therefore, there is an urgent need to develop a highly stable catalytic cracking additive and catalytic cracking composition with high heavy oil conversion capacity and low coke selectivity. Summary of the Invention

[0009] The purpose of this invention is to overcome the problems of low catalytic activity, insufficient macropores, poor stability, and low alkali center content in existing catalytic cracking additives, and to provide a novel catalytic cracking additive and a catalytic composition containing this additive. The catalytic cracking additive possesses high alkali center content, high total pore volume, and high microreactor activity retention. When the catalytic cracking composition containing this additive is used in heavy oil catalytic cracking, it can significantly reduce coke yield and improve light oil selectivity. The purpose of this invention is also to provide a method for preparing this catalytic cracking additive and a heavy oil catalytic cracking method using the catalytic cracking additive or the catalytic cracking composition.

[0010] To achieve the above objectives, the inventors have surprisingly discovered through research that when a catalytic cracking promoter 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 catalytic cracking promoter can simultaneously possess a high content of basic centers, a high pore volume, and a suitable pore size distribution.

[0011] Furthermore, the inventors have surprisingly discovered through research that, in the method for preparing the above-mentioned catalytic cracking additive, by incorporating or loading the specific stabilizing element and the specific activity regulating element in different preparation steps, the stabilizing element and the activity regulating element are distributed in different regions of the additive particles in a specific manner. This can synergistically work with the silicon-aluminum matrix containing a low Si / Al molar ratio to further improve the medium-to-large porosity of the above-mentioned additive, while improving catalytic activity and stability.

[0012] In this specification, the term "matrix" refers to any substance other than the active element, stabilizing element, and clay contained in the catalytic cracking additive; the term "silicon-aluminum matrix" refers to a matrix containing silicon and aluminum, which is mainly generated from silicon-source compounds and aluminum-source compounds used in the preparation of the catalytic cracking additive.

[0013] Therefore, according to a first aspect of the present invention, the present invention provides a catalytic cracking promoter, wherein, based on the total dry weight of the catalytic cracking promoter, the catalytic cracking promoter comprises: 5-50 wt% clay on a dry basis, 5-40 wt% silicon species based on SiO2, 30-80 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 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 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, Group IIIB and Group IVB elements.

[0014] The catalytic cracking promoter according to the present invention has a large total pore volume and a suitable pore size distribution; wherein, as determined by low-temperature nitrogen adsorption, the total pore volume of the catalytic cracking promoter is not less than 0.5 mL / g, preferably 0.6-1.5 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. Furthermore, the above-mentioned catalytic cracking promoter exhibits high catalytic activity and high stability, wherein, after hydrothermal treatment, especially after treatment at 800°C and 100% steam for 17 hours, the microreaction activity retention of the catalytic cracking promoter is not less than 50%, preferably not less than 60%.

[0015] Unlike additives in the prior art, the additives according to the present invention contain a matrix in which the molar amount (mol) of silicon is equal to or less than the molar amount (mol) of aluminum; that is, the content ratio of silicon species and aluminum species in the matrix, expressed as a SiO2 / Al2O3 molar ratio, is less than or equal to 2. The inventors have surprisingly discovered that, compared to the prior art, the catalytic cracking additives according to the present invention, comprising 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 for improving the catalytic activity of the additive and for the transport of inferior oil, achieving efficient conversion of heavy oil and low coke yield in the catalytic cracking process.

[0016] According to one embodiment of the first aspect of the invention, in the adjuvant of the invention, the stabilizing element is distributed inside the adjuvant microspheres, preferably uniformly distributed inside the adjuvant 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 adjuvant microspheres and possibly 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 the microsphere surface layer (thickness, for example, less than 1 micrometer) with a very small thickness.

[0017] According to a preferred embodiment of the first aspect, the catalytic cracking aid comprises, based on the total dry weight of the catalytic cracking aid, 10-45 wt% clay on a dry basis, 8-35 wt% silicon species based on SiO2, 35-75 wt% aluminum species based on Al2O3, 1-10 wt% stabilizing elements based on oxides, and 1-8 wt% activity regulating elements based on oxides; the content ratio of the silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.2-1.5; preferably, based on the total dry weight of the catalytic cracking aid, the total amount of the silicon species based on SiO2 and the aluminum species based on Al2O3 is 45-90 wt%, preferably 50-85 wt%.

[0018] According to a preferred embodiment of the first aspect, wherein 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, in which case the catalytic cracking promoter is measured by pyridine infrared spectroscopy to be Brønsted acid (B acid). The ratio of the amount of acid to the amount of Lewis acid is 0.05-0.5; 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 and Ti, in which case the content of the base center of the adjuvant determined by CO2-TPD method is 0.05-0.5 mmol / g.

[0019] According to one embodiment of the first aspect, the clay is selected from at least one of kaolin, bentonite, montmorillonite, sepiolite, diatomite, rettoitite, attapulgite, halloysite, and hydrotalcite, preferably kaolin.

[0020] According to one embodiment of the first aspect, the total pore volume of the catalytic cracking aid, as determined by low-temperature nitrogen adsorption, is not less than 0.5 mL / g, preferably 0.6-1.5 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, preferably 85%-99%; and / or, the specific surface area of ​​the catalytic cracking aid is 150-350 m² / g.2 / g, preferably 180-300m 2 / g; and / or, the most probable pore size of the catalytic cracking aid is 10-40nm, preferably 15-35nm; and / or, the attrition index of the catalytic cracking aid is not higher than 2.6m% / h (i.e., mass% / hour), preferably 0.5-2.5m% / h.

[0021] In this specification, the term "silicon species" refers to silicon-containing substances or silicon elements other than molecular sieves and clay contained in the catalytic cracking aid; the term "aluminum species" refers to aluminum-containing substances or aluminum elements other than molecular sieves and clay contained in the catalytic cracking aid. In the statement "stabilizing element based on oxides," the term "oxide" refers to the oxide of the stabilizing element source formed after calcination; and in the statement "activity regulating element based on oxides," the term "oxide" refers to the oxide of the stabilizing element source formed after calcination, such as MgO, La₂O₃, CeO₂, Y₂O₃, P₂O₅, ZrO₂, etc.

[0022] According to a second aspect of the present invention, the present invention provides a method for preparing a catalytic cracking promoter, particularly a catalytic cracking promoter according to the first aspect, characterized in that the method comprises the following steps:

[0023] (1) In the presence of a solvent, clay, silicon source, aluminum source, stabilizing element source and optional acid are uniformly mixed to obtain a mixed gel;

[0024] (2) The obtained mixed gel is subjected to aging treatment to obtain a stabilized mixed gel;

[0025] (3) The stabilized mixed gel is spray-dried and optionally calcined to obtain additive microspheres;

[0026] (4) The catalytic cracking aid microspheres are subjected to ammonium ion exchange; and

[0027] (5) Loading an activity regulating element onto an ammonium ion-exchanged auxiliary microsphere, optionally filtering, drying and calcining the auxiliary microsphere loaded with the activity regulating element to obtain a catalytic cracking auxiliary;

[0028] The amount of clay, silicon source, aluminum source, stabilizing element source, and activity regulating element source added is such that the obtained catalytic cracking promoter contains (based on the dry weight of the catalytic cracking promoter): 5-50 wt% clay on a dry basis, 5-40 wt% silicon species based on SiO2, 30-80 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; the content ratio of silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.05-2 (i.e., the Si / Al molar ratio is 0.025-1).

[0029] In the preparation method of the catalytic cracking additive according to the present invention, by loading activity-regulating elements on the surface of the additive microspheres produced by spray drying a stabilized mixed gel and possibly in the pores of a microsphere surface layer with a very small thickness (e.g., less than 1 micrometer), a catalytic cracking additive with a large total pore volume, a wide pore distribution, and high catalytic activity can be obtained. The present invention, through the above preparation method, obtains a catalytic cracking additive containing a specific combination of stabilizing and activity-regulating elements, and a matrix comprising a Si / Al molar ratio of less than 1. The obtained additive exhibits a rich macroporous structure, suitable pore size distribution, excellent catalytic activity, enhanced heavy oil conversion capacity, high light oil yield, and low coke yield. When the combination of the stabilizing and activity-regulating elements is distributed in a specific distribution form within the additive microsphere particles, the above-mentioned properties of the catalytic cracking additive are further improved.

[0030] According to a third aspect of the present invention, the present invention provides a catalytic cracking composition, characterized in that the catalytic cracking composition comprises a catalytic cracking catalyst and a catalytic cracking aid prepared according to the first aspect or the method of the second aspect.

[0031] Because the catalytic cracking composition according to the present invention contains specific catalytic cracking promoters and catalytic cracking catalysts, wherein there is a synergistic effect between the matrix having a SiO2 / Al2O3 molar ratio of less than 2, the specifically distributed stabilizing elements and activity regulating elements contained in the catalytic cracking promoter, and the catalytic cracking promoter has a rich macroporous structure, the catalytic cracking composition has high catalytic activity and resistance to metal contamination. When used in heavy oil catalytic cracking, it allows the avoidance of heavy oil macromolecular condensation coking and over-cracking, and has enhanced heavy oil conversion performance, improved light oil selectivity and reduced coke yield.

[0032] According to a fourth aspect of the present invention, the present invention provides a method for preparing a catalytic cracking composition according to the third aspect above, the method comprising: firstly, preparing a catalytic cracking promoter by means of preparing a catalytic cracking promoter according to the second aspect, and then mixing a catalytic cracking catalyst with the prepared catalytic cracking promoter.

[0033] According to a fifth aspect of the invention, the invention also provides a method for catalytic cracking of heavy oil, wherein heavy oil is contacted with and reacted with a catalytic cracking composition according to the invention.

[0034] Because the catalytic cracking additive of the present invention contains a specific distribution of stabilizing elements, activity regulating elements, and a matrix with a specific SiO2 / Al2O3 molar ratio, the present invention allows for the following beneficial effects through the above five technical solutions:

[0035] The catalytic cracking additive has a large total pore volume and a suitable pore distribution, which results in a high retention of micro-reaction activity after hydrothermal treatment (especially after treatment at 800°C and 100% steam for 17 hours). When it is used together with the catalytic cracking catalyst in the heavy oil catalytic cracking reaction, it is particularly beneficial to the efficient diffusion of inferior oil macromolecules, enhances the resistance to heavy metal pollution, enhances the heavy oil conversion capacity, and reduces coke selectivity. Attached Figure Description

[0036] 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:

[0037] Figure 1 shows the pore distribution of the catalytic cracking aids prepared according to Example 1 and Comparative Example 1 of the present invention. Detailed Implementation

[0038] 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 in the appendix.

[0039] 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.

[0040] 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.

[0041] In this invention, the pore volume, specific surface area, and pore size distribution of the additives are determined by nitrogen physical adsorption.

[0042] 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 the combination clearly unreasonable.

[0043] 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.

[0044] 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.

[0045] As a first series of technical solutions of the first aspect of the present invention, the present invention provides a catalytic cracking promoter (hereinafter referred to as "first series catalytic cracking promoter"), wherein, based on the total dry weight of the catalytic cracking promoter, the catalytic cracking promoter comprises: 5-50 wt% clay on a dry basis, 5-40 wt% silicon species on a SiO2 basis, 30-80 wt% aluminum species on an Al2O3 basis, 0.5-5 wt% stabilizing elements on an oxide basis, and 0.5-10 wt% activity regulating elements 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 elements and Group IVB elements, and the activity regulating element is selected from at least one of Mg and P.

[0046] According to one embodiment of the first series of catalytic cracking aids, the total pore volume of the catalytic cracking aid is not less than 0.5 mL / g, preferably not less than 0.6 mL / g, as determined by the low-temperature nitrogen adsorption method. The pore volume of pores with a diameter of 10-100 nm accounts for more than 80% of the total pore volume, preferably more than 85%.

[0047] According to one embodiment of the first series of catalytic cracking additives, the additive microspheres obtained by spray drying have a sphericity of 0.7 or more, preferably 0.8 or more, and the particle size can have a wide range, preferably substantially in the range of 1-150 micrometers, and the average particle size is 50 micrometers or more, preferably 60-90 micrometers, and more preferably 65-85 micrometers. For recap, in this specification, the term "sphericity of the additive microspheres" refers to the ratio of the surface area of ​​a sphere of the same volume as the additive microspheres to the surface area of ​​the additive 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 selecting a certain number of sample particles according to conventional methods in the art, which will not be elaborated further here.

[0048] According to one embodiment of the first series of catalytic cracking aids, the ratio of Brønsted acid (B acid) to Lewis acid (L acid) in the catalytic cracking aid, as measured by pyridine infrared spectroscopy, is 0.05-0.5; preferably, the ratio is 0.1-0.4, for example, it can be 0.12, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.39, or any value within the range of any two of the above values. Using the above-mentioned preferred ratio of B acid to L acid is more conducive to improving the pre-cracking capability of heavy oil macromolecules, avoiding condensation and coking, further improving heavy oil conversion rate, and reducing coke yield.

[0049] In this invention, the contents of the Brønsted acid center and the Lewis acid center are obtained using pyridine infrared spectroscopy and tested using a Thermo Fisher Nicolet iS10 infrared spectrometer. The specific testing method includes: preparing the sample into a pellet, sealing it in the in-situ cell of the infrared spectrometer, heating it to 200°C, and then testing it under a vacuum of 10... -3 Desorption was performed at Pa for 30 minutes, followed by spectral analysis at room temperature, with a scanning range of 1400-1700 cm⁻¹. -1 The pyridine adsorption infrared spectrum of the sample after desorption at 200℃ can be obtained. Based on the pyridine adsorption infrared spectrum at 1540 cm⁻¹... -1 and 1450cm -1 The area of ​​the characteristic absorption peak is used to calculate the acid ratio of surface Brønsted acid and Lewis acid.

[0050] According to one embodiment of the first series of catalytic cracking additives, based on the total dry weight of the catalytic cracking additives, the catalytic cracking additives comprise: 10-45 wt% clay on a dry basis, 8-35 wt% silicon species on a SiO2 basis, 35-75 wt% aluminum species on an Al2O3 basis, 1-4 wt% stabilizing elements on an oxide basis, and 1-8 wt% activity regulating elements on an oxide basis. For example, in the catalytic cracking additive according to the present invention, the clay content on a dry basis may be 15 wt%, 20 wt%, 25 wt%, or 35 wt%; and / or, the silicon species content on a SiO2 basis may be 8 wt%, 10 wt%, 15 wt%, 20 wt%, or 25 wt%; and / or, the aluminum species content on an Al2O3 basis may be 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, or 65 wt%; and / or, the stabilizing element content on an oxide basis may be 2 wt% or 3 wt%; and / or, the activity regulating element content on an oxide basis may 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 the components of the additive, thereby improving the catalytic performance of the catalytic cracking composition.

[0051] According to one embodiment of the first series of catalytic cracking additives, the content ratio of silicon species and aluminum species, based on the SiO2 / Al2O3 molar ratio, is 0.2-1.5, for example, it can be 0.3, 0.4, 0.6, 0.8, 1, 1.2, 1.4, or 1.5, or any value within the range of any two of the above values. Using the above-mentioned preferred content ratio of silicon species and aluminum species, based on the SiO2 / Al2O3 molar ratio, is beneficial for the catalytic cracking additive to form a larger total pore volume and a suitable pore distribution, which is beneficial for further improving the catalytic activity of the catalytic cracking composition, achieving efficient conversion of heavy oil macromolecules and low coke yield.

[0052] For the first series of catalytic cracking promoters, the total amount of silicon and aluminum species can vary within a wide range, as long as the respective amounts and ratios of silicon and aluminum species in the catalytic cracking promoter meet the aforementioned range. According to one embodiment, the total amount of silicon and aluminum species, calculated as oxides, is 45-90% by weight relative to the total weight of the catalytic cracking promoter. For example, it can be 46%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 89% by weight, or any value within the range of any two of the above values, preferably 50-80% by weight. Using the above-mentioned preferred total amount is beneficial for further endowing the catalytic cracking promoter with a rich macroporous structure and excellent activity, thereby improving the catalytic performance of the catalytic cracking composition containing the promoter.

[0053] According to one embodiment of the first series of catalytic cracking aids, the total pore volume of the catalytic cracking aid is determined by low-temperature nitrogen adsorption method to be 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 aid can be 0.7 mL / g, 0.8 mL / g, 1 mL / g, 1.2 mL / g, 1.4 mL / g, or 1.5 mL / g, or any value within any range of any two of the above values; the pore volume with a diameter of 10-100 nm can account for 85%, 87%, 89%, 91%, 93%, 95%, 97%, or 99% of the total pore volume, or any value within any range of any two of the above values. Because the catalytic cracking additive has a large total pore volume and a suitable pore distribution, it is beneficial to improve the activity of the catalytic cracking additive, thereby enabling the catalytic cracking composition containing the additive to have excellent heavy oil cracking capability, high light oil selectivity and low coke yield.

[0054] As an explanation, the method for determining the pore volume of the catalytic cracking additive of the present invention by low-temperature nitrogen adsorption includes: using a Micromeritics ASAP 2405NV1.01 automated adsorption instrument, low-temperature static nitrogen adsorption capacity method, with the sample at 1.33 × 10⁻⁶ pores. -2 The 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.

[0055] According to one embodiment of the first series of catalytic cracking additives, the specific surface area of ​​the catalytic cracking additive is 150-350 m². 2 / g, for example, can be 160m 2 / g、200m 2 / g、250m 2 / g、300m 2 / g or 340m 2 / g, and any value within the range of any two of the above values, preferably 180-300m. 2 / g.

[0056] According to one embodiment of the first series of catalytic cracking additives, the most probable pore size of the catalytic cracking additive is 10-40 nm, for example, it can be 11 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm or 39 nm, or any value within the range of any two of the above values, preferably 15-30 nm. 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.

[0057] According to one embodiment of the first series of catalytic cracking aids, the microreaction activity retention of the catalytic cracking aid after hydrothermal treatment (especially treatment at 800°C and 100% steam for 17 hours) is not less than 30%, preferably not less than 35%, and particularly 35-60%. For example, it can be not less than 36%, 40%, 45%, 50%, 55%, or 59%, or any value within the range of any two of the above values. The catalytic cracking aid exhibits high microreaction activity after hydrothermal treatment under the above extreme conditions. Combined with the aforementioned specific macroporous structure, acidity, and specific stabilizing and activity-regulating elements, it is beneficial to further enhance heavy oil conversion capacity, reduce coke yield, and improve the selectivity of light oil.

[0058] For review, the definition of the microreaction activity retention of the catalytic cracking additive is as follows: Microreaction activity retention of the additive = (Microreaction activity of the additive after treatment / Microreaction activity of the additive before treatment) * 100%. The test method for the microreaction activity of the catalytic cracking additive after treatment at 800℃ and 100% steam for 17 hours includes: first, aging the additive at 800℃ and 100% steam for 17 hours in a fixed-bed aging device, and then conducting a microreaction activity test. The microreaction activity test method includes: evaluating the light oil microreaction activity of the sample 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), where the sample loading is 5.0 g, the reaction temperature is 460℃, the feed oil is straight-run light diesel oil with a distillation range of 235-337℃, the product composition is analyzed by gas chromatography, and finally, the light oil microreaction activity is calculated based on the product composition.

[0059] For the first series of catalytic cracking additives, the type of stabilizing element can be selected from a wide range, as long as it is selected from Group IIIB and / or Group IVB elements. According to one embodiment of the first series of catalytic cracking additives, the stabilizing element is selected from at least one of La, Ce, Y, Zr, and Ti, preferably at least one of La, Ce, and Zr. Using the above-mentioned preferred stabilizing elements in the catalytic cracking additive is beneficial for stabilizing the pore structure of the additive, synergistically optimizing the activity of the macroporous structure of the additive, improving the catalytic cracking reaction efficiency, increasing the selectivity of light oils, and reducing coke yield.

[0060] This invention does not particularly limit the type of clay used in the first series of catalytic cracking additives; various clays conventionally used in the art can be used in this invention. According to one embodiment of the first series of catalytic cracking additives, the clay is selected from at least one of kaolin, bentonite, montmorillonite, sepiolite, diatomaceous earth, attapulgite, attapulgite, halloysite, and hydrotalcite, preferably from at least one of kaolin, bentonite, and attapulgite. Using the above-mentioned preferred clays in the catalytic cracking additives is beneficial for further optimizing the pore structure and pore distribution of the catalytic cracking additives and improving their wear resistance.

[0061] The catalytic cracking aid of the present invention may also include other commonly used matrices. For example, the commonly used matrices may be selected from at least one of silicon oxide and its precursors, aluminum oxide and its precursors, and magnesium oxide and its precursors.

[0062] As a second series of technical solutions of the first aspect of the present invention, the present invention provides a catalytic cracking aid (hereinafter referred to as "second series catalytic cracking aid"), characterized in that the catalytic cracking aid comprises, based on the total dry weight of the catalytic cracking aid: 5-50 wt% of clay on a dry basis, 5-40 wt% of silicon species on a SiO2 basis, 30-80 wt% of aluminum species on an Al2O3 basis, 0.5-15 wt% of stabilizing elements on an oxide basis, and 0.5-10 wt% of activity regulating elements 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 Mg, and the activity regulating element is selected from at least one of P, B, Group IIIB elements and Group IVB elements.

[0063] According to one embodiment of the second series of catalytic cracking additives, based on the total dry weight of the catalytic cracking additives, the catalytic cracking additives comprise: 10-45 wt% clay on a dry basis, 8-35 wt% silicon species on a SiO2 basis, 35-75 wt% aluminum species on an Al2O3 basis, 1-10 wt% stabilizing elements selected from magnesium on an oxide basis, and 1-8 wt% activity regulating elements on an oxide basis, wherein the content ratio of silicon species and aluminum species on a SiO2 / Al2O3 molar ratio is 0.2-1.5. For example, in the second series of catalytic cracking additives, the clay content on a dry basis can be 15 wt%, 20 wt%, 25 wt%, or 35 wt%; and / or, the silicon species content on a SiO2 basis can be 8 wt%, 10 wt%, 15 wt%, 20 wt%, or 25 wt%; and / or, the aluminum species content on an Al2O3 basis can be 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, or 65 wt%; and / or, the magnesium content on a magnesium oxide basis can be 2 wt%, 3 wt%, 5 wt%, 6 wt%, or 7 wt%; and / or, the content of the activity-regulating elements on an oxide basis 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 composition.

[0064] According to one embodiment of the second series of catalytic cracking aids, the alkali center content of the catalytic cracking aid, determined by CO2-TPD, is 0.05-0.5 mmol / g; preferably 0.1-0.4 mmol / g, for example, 0.1 mmol / g, 0.15 mmol / g, 0.2 mmol / g, 0.25 mmol / g, 0.3 mmol / g, 0.35 mmol / g, or 0.4 mmol / g, or any value within any range of two of the above values. In this invention, using the above-mentioned catalytic cracking aid with the preferred alkali center content in combination with the catalytic cracking catalyst is more beneficial for improving the light oil selectivity of the catalytic cracking composition and reducing coke yield.

[0065] According to one embodiment of the second series of catalytic cracking aids, the total pore volume of the catalytic cracking aid is determined by low-temperature nitrogen adsorption method to be not less than 0.5 mL / g, preferably 0.6-1.5 mL / g; for example, the total pore volume of the catalytic cracking aid can be 0.7 mL / g, 0.8 mL / g, 1 mL / g, 1.2 mL / g, 1.4 mL / g or 1.5 mL / g, and any value within the range of any two of the above values; 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%, for example, the pore volume of pores with a diameter of 10-100 nm can account for 86%, 87%, 89%, 91%, 93%, 95%, 97% or 98% of the total pore volume, and any value within the range of any two of the above values. The catalytic cracking aid according to the present invention has a large total pore volume and a suitable pore distribution, which makes the catalytic cracking composition containing the catalytic cracking aid have a high light oil yield and effectively reduce slurry oil yield and coke selectivity.

[0066] According to one embodiment of the second series of catalytic cracking additives, the additive microspheres obtained by spray drying have a sphericity of 0.7 or more, preferably 0.8 or more, and their particle size can have a wide range, preferably substantially in the range of 1-150 micrometers, and their average particle size is 60-90 micrometers, preferably 65-85 micrometers; wherein the term "average particle size" refers here to the number-average diameter of the particles, and is measured by selecting a certain number of sample particles using conventional methods in the art.

[0067] Because the second series of catalytic cracking aids contains a specific amount of magnesium and specific amounts and types of activity-regulating elements, the catalytic cracking aids exhibit high micro-reaction activity retention after hydrothermal treatment, especially after treatment at 800°C and 100% steam for 17 hours. They also possess a rich macroporous structure and suitable pore distribution. Furthermore, due to the presence of a matrix with a SiO2 / Al2O3 molar ratio of less than 2, the catalytic cracking aids have a specific alkali center content. This results in the catalytic cracking composition containing the catalytic cracking aids exhibiting excellent hydrothermal stability and high activity stability. When used in the heavy oil catalytic cracking process, it can increase the yield of light oil while reducing the oil slurry yield and coke selectivity.

[0068] According to one embodiment of the second series of catalytic cracking aids, the microreactor activity retention rate of the catalytic cracking aid after treatment at 800°C and 100% steam for 17 hours is not less than 60%, preferably 65%-85%, for example, it can be 66%, 68%, 70%, 73%, 75%, 78%, 80%, 83%, or 84%, or any value within any range of any two of the above values. The catalytic cracking aid according to the present invention can maintain high microreactor activity after treatment under the above extreme conditions for 17 hours. The above-preferred catalytic cracking aid has superior activity stability and better catalytic effect.

[0069] According to one embodiment of the second series of catalytic cracking additives, the content ratio of silicon species and aluminum species, based on the SiO2 / Al2O3 molar ratio, is 0.2-1.5, for example, it can be 0.3, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, or 1.5, or any value within the range of any two of the above values. Using the above-mentioned preferred SiO2 / Al2O3 molar ratio is more conducive to forming a larger total pore volume and suitable pore distribution in the catalytic cracking additive, which is beneficial to further improving the activity and stability of the catalytic cracking composition, achieving efficient heavy oil conversion and low coke yield.

[0070] For the second series of catalytic cracking promoters, 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 promoter meet the aforementioned range. Preferably, relative to the total weight of the catalytic cracking promoter, the total amount of silicon and aluminum species, calculated as oxides, is 45-90% by weight, for example, 46%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% by weight, or any value within any range of any two of the above values, preferably 50-80% by weight. Using the above-mentioned preferred amounts is beneficial for further endowing the catalytic cracking promoter with a rich macroporous structure and excellent activity stability.

[0071] According to one embodiment of the second series of catalytic cracking additives, the aluminum species mainly exist in the form of aluminum silicate. This is beneficial for further improving the activity stability and hydrothermal stability of the catalytic cracking additives, and for further optimizing the distribution of active centers, thereby improving the selectivity of light oil products and reducing slurry oil yield and coke selectivity. In this invention, the presence of aluminum silicate can be confirmed by XRD characterization (an aluminum silicate diffraction peak appears at 22.3 degrees).

[0072] For the second series of catalytic cracking additives, the types of activity regulating elements can be selected from a wide range. Preferably, the activity regulating element is selected from at least one of P, B, La, Ce, Y, Zr, and Ti, and more preferably from at least one of P, B, La, and Ce. Using the above-mentioned preferred activity regulating elements in the catalytic cracking additives is more conducive to their synergistic effect with magnesium, improving the efficiency of the catalytic cracking reaction, increasing the selectivity of light oil products, and reducing slurry oil yield and coke selectivity.

[0073] For the second series of catalytic cracking additives, there is no particular limitation on the type of clay; various clays conventionally used in the art can be used in the catalytic cracking additives. Preferably, the clay is selected from at least one of kaolin, bentonite, montmorillonite, sepiolite, diatomaceous earth, attapulgite, attapulgite, and halloysite, with kaolin being the most preferred. Using the above-mentioned preferred clays in the catalytic cracking additives is beneficial for further optimizing the pore structure and pore distribution of the catalytic cracking additives and improving their wear resistance.

[0074] For the second series of catalytic cracking additives, their specific surface area can vary over a wide range. Preferably, the specific surface area of ​​the catalytic cracking additive is 150-350 m². 2 / g, for example, can be 160m 2 / g、200m 2 / g、250m 2 / g、300m 2 / g or 340m 2 / g, and any value within the range of any two of the above values, preferably 180-300m. 2 / g.

[0075] For the second series of catalytic cracking aids, the most probable pore size can vary within a wide range. Preferably, the most probable pore size of the catalytic cracking aid is 10-40 nm, more preferably 15-35 nm. 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.

[0076] The second series of catalytic cracking additives have excellent wear resistance properties, for example, a wear index of not more than 2.6 m% / h, preferably 0.5-2.5 m% / h. This is beneficial for the catalytic cracking additives to maintain good morphology and catalytic activity, thereby further improving the catalytic effect of the catalytic cracking composition containing the additive.

[0077] According to a first series of technical solutions of a second aspect of the present invention, the present invention provides a method for preparing catalytic cracking additives according to the first series (hereinafter referred to as "first series preparation method"), characterized in that the method comprises the following steps:

[0078] (1) In the presence of a solvent, clay, a silicon source, an aluminum source, and an optional acid are uniformly mixed to obtain a mixed gel. Then, a stabilizing element source is added and uniformly mixed to obtain a mixed slurry.

[0079] (2) The pH of the obtained mixed slurry is adjusted to 9-12 and aged to obtain a stabilized mixed gel;

[0080] (3) The stabilized mixed gel is spray-dried and optionally calcined to obtain additive microspheres;

[0081] (4) Allow the auxiliary microspheres to undergo ammonium ion exchange, and

[0082] (5) Loading an active regulating element onto an ammonium ion-exchanged additive microsphere, optionally filtering, drying and calcining the catalytic cracking additive microsphere loaded with the active regulating element to obtain a catalytic cracking additive.

[0083] The clay, silicon source, aluminum source, stabilizing element source, and activity regulating element source are added in such amounts that the resulting catalytic cracking promoter comprises (based on the dry weight of the catalytic cracking promoter): 5-50 wt% clay on a dry basis, 5-40 wt% silicon species based on SiO2, 30-80 wt% aluminum species based on Al2O3, 0.5-5 wt% stabilizing element based on oxides, and 0.5-10 wt% activity regulating element based on oxides; the content ratio of silicon species and aluminum species based on the SiO2 / Al2O3 molar ratio is 0.05-2; 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.

[0084] According to a preferred embodiment of the first series of preparation methods, the amount of clay, aluminum source, silicon source, stabilizing element source and activity regulating element source added is such that the obtained catalytic cracking promoter comprises (based on the total dry weight of the catalytic cracking promoter): 10-45 wt% clay on a dry basis, 8-35 wt% silicon species based on SiO2, 35-75 wt% aluminum species based on Al2O3, 1-4 wt% stabilizing element based on oxides and 1-8 wt% activity regulating element based on oxides.

[0085] The inventors have surprisingly discovered that in the first series of preparation methods, mixing the mixed gel with a stabilizing element source, adjusting the mixed slurry to a specific pH, and subjecting it to aging treatment facilitates the formation of a macroporous structure, while simultaneously increasing the pore wall thickness and improving the hydrothermal stability of the macroporous structure. Subsequently, loading activity-regulating elements onto the additive microspheres helps to control the distribution of active sites on the additive surface, optimize the Brønsted acid / Low acid ratio, and regulate the acid center density, thereby preventing heavy oil macromolecular condensation and coking, and over-cracking. Through the above preparation methods, a catalytic cracking additive containing a matrix with a low SiO2 / Al2O3 molar ratio, a specifically distributed stabilizing element, and an activity-regulating element is obtained. This catalytic cracking additive has a large total pore volume, resulting in catalytic cracking compositions containing the additive exhibiting excellent catalytic activity, strong heavy oil conversion performance, improved light oil selectivity, and reduced coke yield.

[0086] In the first series of preparation methods, the type of stabilizing element source can be selected from a wide range. Preferably, the stabilizing element source is a soluble compound containing the stabilizing element, and more preferably, a salt containing the stabilizing element. The type of salt 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, and more preferably, nitrate and / or chloride. Using the above-mentioned preferred stabilizing elements is beneficial for stabilizing the pore structure of the catalytic cracking additive, synergistically optimizing the activity of the macroporous structure of the additive, improving the catalytic cracking reaction efficiency, increasing the selectivity of light oil, and reducing coke yield.

[0087] According to one embodiment of the first series of preparation methods, in step (1), the solid content of the 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 mixed gel in the preparation method helps to ensure uniform mixing and sufficient reaction of the components, optimize the aging treatment effect, and improve the catalytic performance of the catalytic cracking aid.

[0088] In the first series of preparation methods, there are no particular limitations on the preparation method of the mixed gel, as long as the solid content of the mixed gel meets the above-mentioned range. Preferably, in step (1), the preparation method of the mixed gel includes: uniformly mixing a mixed slurry of clay, aluminum source, and silicon source with acid in the presence of a solvent. More preferably, the preparation method of the mixed gel includes: uniformly mixing a mixed slurry of clay and aluminum source with acid, and then adding a silicon source and mixing it uniformly. The above-mentioned preferred preparation methods are beneficial for forming a mixed gel with uniform structure and good performance. In this invention, the solvent contained in the aluminum source solution is preferably water. In this invention, there are no particular limitations on the method, equipment, and conditions for carrying out the mixing, as long as the solvent, clay, aluminum source, and silicon source are uniformly mixed. Preferably, the duration of each mixing is independently 0.5-5 hours, for example, it can be 0.6 hours, 1 hour, 2 hours, 3 hours, 4 hours, or 4.5 hours, and any value within the range of any two of the above values.

[0089] In 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 in this invention. Preferably, the aluminum source is selected from at least one of aluminum sol, aluminum isopropoxide, aluminum sulfate, aluminum chloride, aluminum nitrate, boehmite, aluminum hydroxide, aluminum oxide, and sodium aluminate, and more preferably from at least one of aluminum sol, aluminum sulfate, and boehmite.

[0090] In 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 in this invention. Preferably, the silicon source is selected from at least one of water glass, alkaline silica sol, acidic silica sol, neutral silica sol, tetraethyl orthosilicate, and tetramethoxysilane, and is more preferably water glass and / or alkaline silica sol.

[0091] In step (1) of the first series of preparation methods, the amount of acid used can vary within a wide range. Preferably, the amount of acid used is such that the pH of the resulting mixed gel is 1-4, for example, 1.5, 2, 3, or 3.5, or any value within the range of any two of the above values. The above-mentioned preferred pH range is more conducive to the formation of a stable mixed gel.

[0092] In the first series of preparation methods, there is no particular limitation on the type of acid. Various substances that can provide acidity commonly used in the art can be used in the methods of the present invention. 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.

[0093] In the first series of preparation methods, 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 mixed gel and for ensuring the uniform distribution and firm binding of stabilizing elements within the gel.

[0094] According to one embodiment of the first series of preparation methods, in step (2), before aging treatment, the pH of the mixed slurry is adjusted to 9-12 by contacting it with alkali, for example 9, 9.5, 10, 10.5, 11, 11.5, 12, and any value in the range of any two of the above values, preferably 9.5-11.5.

[0095] In the first series of preparation methods, 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, and more preferably from ammonia.

[0096] In the first series of preparation methods, there are no particular limitations on the spray drying method, equipment, and conditions; conventional spray drying methods, equipment, and conditions used in the art can be employed. Preferably, the exhaust gas temperature during spray drying is 100-300°C, more preferably 120-200°C. Using the above-mentioned preferred spray drying conditions facilitates the rapid drying of the atomized slurry into spherical particles, thereby obtaining well-shaped additive microspheres and further improving the wear resistance of the prepared catalytic cracking composition. Preferably, the additive microspheres have a sphericity greater than 0.7, preferably greater than 0.8, and a wide range of particle sizes, with an average particle size of 60-90 micrometers, preferably 65-85 micrometers. For recap, in this specification, the sphericity of the additive microspheres represents the ratio of the surface area of ​​a sphere of the same volume to the surface area of ​​the additive microsphere, which is measured using conventional methods in the art and will not be elaborated further here.

[0097] In the first series of preparation methods, there are no particular limitations on the mixing method, equipment, and conditions in step (1), as long as the stable element source and the mixed gel are mixed evenly. Preferably, the mixing duration is 0.5-5 hours, for example, it can be 0.6 hours, 1 hour, 2 hours, 3 hours, 4 hours, or 4.5 hours, or any value within the range of any two of the above values.

[0098] In the first series of preparation methods, there is no particular limitation on the type of activity-regulating element source used in step (5). Preferably, the activity-regulating element source is a soluble compound containing an activity-regulating element, such as a soluble salt, acid, or base, preferably a sulfate, nitrate, chloride, acetate, or oxalate, 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 pyrophosphate, more preferably selected from at least one of magnesium sulfate, magnesium nitrate, magnesium oxalate, ammonium dihydrogen phosphate, and diamine hydrogen phosphate.

[0099] According to one embodiment of the first series of preparation methods, in step (4), the ammonium ion exchange ensures that the sodium oxide content on the surface of the additive microspheres is no higher than 0.3% by weight, preferably 0.05-0.25% by weight. In the method of the present invention, the ammonium ion exchange ensures that the sodium oxide content on the surface of the additive microspheres is within the above-mentioned preferred range, which is beneficial to optimizing the acidity and active sites on the surface of the additive, thereby improving the catalytic activity of the catalytic cracking composition containing the catalytic cracking additive and reducing the condensation coking and over-cracking of heavy oil macromolecules. In the present invention, the sodium oxide content on the surface of the additive microspheres is determined using the method Q / SH 361 906-2018 (Q / SH 3360-205).

[0100] In the first series of preparation methods, the ammonium ion exchange can be carried out using methods conventional in the art. Specifically, the method of ammonium ion exchange includes contacting the auxiliary microspheres and the ammonium salt in the presence of a solvent.

[0101] According to one embodiment of the first series of preparation methods, in step (4), the mass ratio of the catalytic cracking aid microspheres and the ammonium salt, on a dry basis, is 1:0.01-0.6. For example, it can be 1:0.01, 1:0.02, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, or 1:0.6, or any value within the range of any two of the above values, preferably 1:0.02-0.5. Using the above-mentioned preferred mass ratio helps ensure sufficient exchange of ammonium ions with sodium oxide while avoiding excessive exchange, optimizing the acidity and active site distribution on the aid surface, thereby improving the catalytic activity of the catalytic cracking composition containing the catalytic cracking aid, promoting heavy oil conversion, and reducing coke yield.

[0102] In step (4) of the first series of preparation methods, the amount of solvent used in the ammonium ion exchange can vary within a wide range. Preferably, the mass ratio of the auxiliary microspheres to the solvent, on a dry basis, is 1:5-20, more preferably 1:8-15. Using the above-mentioned preferred mass ratio is beneficial to improving the efficiency of ammonium ion exchange. The solvent used in this invention is preferably water.

[0103] In step (4) of the first series of preparation methods, the type of ammonium salt used for ammonium ion exchange is not particularly limited, as long as it enables the auxiliary 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.

[0104] In step (4) of the first series of preparation methods, the conditions for carrying out the ammonium ion exchange can be selected within a wide range. Preferably, the conditions for carrying out the ammonium ion exchange include: a temperature of 20-100℃, more preferably 20-80℃; and a time of 10-120 minutes, more preferably 20-90 minutes. Using the above-mentioned preferred ammonium ion exchange conditions is beneficial for reducing sodium oxide content and optimizing acidity and active sites.

[0105] In the preparation method according to the present invention, by first subjecting the additive microspheres to ammonium ion exchange and then loading them with activity regulating elements, it is beneficial to both reduce the sodium oxide content of the catalytic cracking additive and increase the loading of the activity regulating elements. By adjusting the active sites on the surface of the additive, the catalytic performance of the catalytic cracking composition containing the catalytic cracking additive is improved, effectively promoting the conversion of heavy oil, improving the selectivity of light oil, and reducing the coke yield.

[0106] In step (5) of the first series of preparation methods, the method of loading the activity regulating element is not particularly limited. Preferably, the loading method includes: contacting the activity regulating element source with ammonium ion-exchanged auxiliary agent microspheres in the presence of a solvent to perform impregnation and / or ion exchange.

[0107] In the first series of preparation methods, there are no particular limitations on the method used for loading the active regulating element in step (5). Preferably, the loading of the active regulating element is carried out in the following manner: in the presence of a solvent, the source of the active regulating element is mixed and contacted with ammonium ion-exchanged auxiliary microspheres to perform impregnation and / or ion exchange; wherein, there are no particular limitations on the method of impregnation, and impregnation methods and conditions conventionally used in the art can be used, so that the active regulating element is mainly loaded on the surface of the auxiliary microspheres and possibly loaded in small quantities in the pores of the surface layer (thickness, for example, less than 1 micrometer). Preferably, the impregnation method is a saturated impregnation method. More preferably, the ammonium ion-exchanged auxiliary microspheres are contact impregnated with a solution of a soluble compound containing the active regulating element. Preferably, the conditions for 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 active 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.

[0108] According to one embodiment of the first series of preparation methods, in step (5), the mass ratio of the ammonium ion-exchanged auxiliary microspheres to the active regulating element source (based on oxides) is 1:0.005-0.1, for example, it can be 1:0.005, 1:0.01, 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09 or 1:0.1, and any value within the range of any two of the above values, preferably 1:0.01-0.08. Using the above-mentioned preferred mass ratio in the preparation method of the present invention is beneficial for optimizing the Brønsted acid / Lønsted acid ratio of the obtained auxiliary, thereby improving the catalytic performance of the catalytic cracking composition containing the catalytic cracking auxiliary and exhibiting excellent catalytic effect.

[0109] For the first series of preparation methods, the amount of solvent used in the loaded activity regulating element can vary within a wide range. Preferably, the mass ratio of the ammonium ion-exchanged auxiliary agent microspheres to the solvent, on a dry basis, is 1:5-15, more preferably 1:5-10. Using the above-mentioned preferred mass ratio in the preparation method of the present invention is beneficial for promoting the uniform distribution of the activity regulating element. The solvent used in the present invention is preferably water.

[0110] For the first series of preparation methods, when the active regulating element is two or more elements, the loading can be carried out in one step or in multiple steps, and the present invention does not have any particular limitation on this.

[0111] In step (5) of the first series of preparation methods, the contact conditions between the additive microspheres and the active regulating element source can be selected within a wide range; preferably, the contact conditions include: a temperature of 20-100℃, more preferably 20-80℃; and a time of 10-120 minutes, more preferably 20-90 minutes. Using the above-mentioned preferred contact conditions helps ensure that the active regulating element is fully loaded onto the surface of the additive microspheres or into the pores of the surface layer, thereby optimizing the catalytic performance and catalytic effect of the catalytic cracking composition containing the catalytic cracking additive.

[0112] According to one embodiment of the first series of preparation methods, in step (5), the additive microspheres loaded with active regulating elements are filtered, dried and calcined to obtain a catalytic cracking additive.

[0113] In step (5) of the first series of preparation methods, the calcination conditions can be selected within a wide range. Preferably, the calcination conditions include: a temperature of 400-600℃, more preferably 450-550℃; and a time of 0.5-3 hours, more preferably 1-2.5 hours. Using the above-mentioned preferred calcination conditions in the preparation method of the present invention is beneficial for fixing the active regulating elements and optimizing the performance of the catalytic cracking composition.

[0114] According to one embodiment of the first series of preparation methods, step (5) further includes filtering and drying the mixture of the additive microspheres containing the loaded active regulating element and the liquid phase before calcination.

[0115] In the preparation method according to the present invention, there are no particular limitations on the method, equipment, and conditions for performing the drying. Drying methods, equipment, and conditions conventionally used in the art can be employed, for example, spray drying. Preferably, the drying temperature is 80-200°C, and the time is 0.5-24 hours.

[0116] 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 additives (hereinafter referred to as the "second series preparation method"), characterized in that the method comprises the following steps:

[0117] (1) In the presence of a solvent, clay, silicon source, aluminum source, magnesium source and optional acid are uniformly mixed to obtain a silicon-aluminum-magnesium mixed gel.

[0118] (2) Adjust the pH of the mixed gel to 9-12 and age the resulting mixed gel to obtain a stabilized mixed gel;

[0119] (3) The stabilized mixed gel is spray-dried and optionally calcined to obtain additive microspheres;

[0120] (4) The additive microspheres are subjected to ammonium ion exchange to obtain ammonium ion-exchanged additive microspheres, and

[0121] (5) Loading an activity regulating element onto an ammonium ion-exchanged additive microsphere, optionally filtering, drying and calcining the catalytic cracking additive microsphere loaded with the activity regulating element; to obtain a catalytic cracking additive;

[0122] The amount of clay, silicon source, aluminum source, magnesium source, and activity regulating element source added is such that the obtained catalytic cracking promoter comprises (based on the dry weight of the catalytic cracking promoter): 5-50 wt% clay on a dry basis, 5-40 wt% silicon species based on SiO2, 30-80 wt% aluminum species based on Al2O3, 0.5-15 wt% magnesium based on oxides, and 0.5-10 wt% activity regulating element based on oxides; the SiO2 / Al2O3 molar ratio of the silicon species and aluminum species is 0.05-2; the activity regulating element is selected from at least one of group P, B, group IIIB elements, and group IVB elements.

[0123] According to one embodiment of the second series of preparation methods, the amount of clay, aluminum source, silicon source, stabilizing element source and activity regulating element source added is such that the obtained catalytic cracking promoter comprises (based on the total dry weight of the catalytic cracking promoter): 10-45 wt% clay on a dry basis, 8-35 wt% silicon species based on SiO2, 35-75 wt% aluminum species based on Al2O3, 1-10 wt% stabilizing element magnesium based on oxides and 1-8 wt% activity regulating element based on oxides.

[0124] 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, and Ti, preferably from at least one of P, B, La, and Ce. Using the above-mentioned preferred active regulating element is more conducive to its synergistic effect with magnesium, improving the efficiency of catalytic cracking reaction, increasing the selectivity of light oil products, and reducing slurry oil yield and coke selectivity.

[0125] According to one embodiment of the second series of preparation methods, in step (1), magnesium is present in the gel skeleton by preparing a silicon-aluminum-magnesium mixed gel, which is beneficial to improve the catalytic activity of the catalytic cracking aid, enhance the stability of the catalytic cracking aid, and optimize the pore structure, so that the catalytic cracking composition containing the catalytic cracking aid has a better catalytic effect in the heavy oil catalytic cracking reaction.

[0126] According to one embodiment of the second series of preparation methods, 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 the components, optimizing the aging treatment effect, improving the catalytic performance of the catalytic cracking composition, and optimizing the catalytic effect.

[0127] According to one embodiment of the second series of preparation methods, in step (1), the solvent, clay, silicon source, aluminum source, and magnesium source can be uniformly mixed in one step, or they can be uniformly mixed in multiple steps. Preferably, the mixture of clay and aluminum source is first uniformly mixed with acid, then the silicon source is added and uniformly mixed, and then the magnesium source is added and uniformly mixed. The above-mentioned preferred mixing method is beneficial for forming a silicon-aluminum-magnesium mixed gel with a uniform structure and good properties. The solvent is preferably water.

[0128] In the second series of preparation methods, there are no particular limitations on the mixing methods and conditions in each of the above steps, as long as it is ensured that the components are mixed uniformly. Preferably, the duration of each mixing step is independently 0.5-5 hours, for example, it can be 0.6 hours, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours or 4.9 hours, or any value within the range of any two of the above values.

[0129] According to one embodiment of the second series of preparation methods, the type of magnesium source can be selected from a wide range. 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, and more preferably selected from at least one of magnesium oxide, magnesium sulfate, magnesium nitrate, and magnesium acetate.

[0130] Other preferred embodiments involved in each step of the second series of preparation methods are the same as those in the first series of preparation methods, and will not be repeated here.

[0131] According to a third aspect of the present invention, the present invention provides a catalytic cracking composition comprising a catalytic cracking catalyst and a catalytic cracking aid according to the first aspect.

[0132] According to one embodiment of the third aspect of the present invention, the mass ratio of the catalytic cracking catalyst to the catalytic cracking promoter is 1:0.05-0.8, preferably 1:0.15-0.6; for example, it can be 1:0.15, 1:0.2, 1:0.3, 1:0.4, 1:0.5, or 1:0.6, or any value within the range of any two of the above values. Using the above-mentioned preferred mass ratio in the catalytic cracking composition of the present invention is more conducive to improving the catalytic activity of the catalytic cracking composition, thereby further promoting heavy oil conversion, improving light oil selectivity, and reducing coke production.

[0133] According to one embodiment of the third aspect of the present invention, the type of catalytic cracking catalyst can be selected from a wide range and can be various catalysts conventionally used in the art for heavy oil catalytic cracking reactions. Preferably, based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 0.1-10 wt% rare earth metal elements as oxides, 40-60 wt% aluminum species as Al2O3, and 20-50 wt% silicon species as SiO2. More preferably, based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 0.5-6 wt% rare earth metal elements as oxides, 45-58 wt% aluminum species as Al2O3, 25-45 wt% silicon species as SiO2, and 0.05-0.3 wt% sodium as oxides. Using the above-preferred catalytic cracking catalyst is more advantageous for synergistic effects with the catalytic cracking promoter according to the present invention, significantly promoting heavy oil conversion, improving light oil selectivity, and reducing coke yield.

[0134] According to a fourth aspect of the present invention, the present invention provides a method for preparing a catalytic cracking composition according to the third aspect above, the method comprising first preparing a catalytic cracking promoter, and then mixing a catalytic cracking catalyst with the prepared catalytic cracking promoter; wherein the catalytic cracking promoter is prepared according to the method for preparing a catalytic cracking promoter according to the second aspect.

[0135] The catalytic cracking composition provided by this invention exhibits high catalytic activity and strong heavy oil conversion performance due to the synergistic effect of specific catalytic cracking promoters and catalysts. Specifically, the catalytic cracking promoters include a matrix with a SiO2 / Al2O3 molar ratio of less than 2, a specific distribution of stabilizing and activity-regulating elements, a rich macroporous structure, and a high Brønsted acid content. When used in heavy oil catalytic cracking, this composition can prevent heavy oil macromolecular condensation and coking, as well as over-cracking, and exhibits high light oil selectivity and low coke yield.

[0136] According to a fifth aspect of the present invention, the present invention also provides a method for catalytic cracking of heavy oil, wherein heavy oil is contacted with a catalytic cracking composition according to the present invention and subjected to a cracking reaction.

[0137] In the heavy oil catalytic cracking method according to the present invention, since the catalytic cracking composition is used in the heavy oil catalytic cracking reaction, the condensation of heavy oil macromolecules to form coke and over-cracking can be avoided, thereby obtaining an improved heavy oil conversion rate, effectively improving the selectivity of light oil and reducing the coke yield.

[0138] The catalytic cracking composition according to the present invention is particularly suitable for heavy oil catalytic cracking methods, especially for the conversion of inferior oils, avoiding coking due to the condensation of heavy oil macromolecules and over-cracking, thereby increasing the yield of light oil while reducing the oil slurry yield and reducing coke selectivity.

[0139] Example

[0140] The present invention will be further illustrated below with examples and comparative examples, but the present invention is not limited thereto. In the following examples and comparative examples:

[0141] Unless otherwise specified, the room temperature refers to 25±5℃.

[0142] The raw materials used in the preparation of the additives are as follows: kaolin with a solid content of 79% by weight; alumina content of 22% by weight in aluminum sol; aluminum sulfate solution with a concentration of 90 g / L (calculated as Al2O3); boehmite with a solid content of 65%; water glass with a concentration of 250 g / L (calculated as SiO2) and a density of 1.26 g / mL; alkaline silica sol with a silica content of 30%; and catalytic cracking catalyst (brand name HSC) provided by Sinopec Catalyst Company, the main properties of which are listed in Table 2.

[0143] The specific surface area and pore volume of the additive microspheres were determined as follows: A Micromeritics ASAP 2405N V1.01 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 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 according to the BET formula, and 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 D 4641) standard, and the pore volume of the 10-100nm pore portion of the sample was calculated using the BJH desorption branch.

[0144] The strength of catalytic cracking additives is determined as follows: A certain amount of sample 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 wear index of the additive, expressed in m% / h. The method and standard are: NB / SH / T0964-2017.

[0145] The micro-reaction activity of the catalytic cracking additive was determined as follows: The micro-reaction 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 sample loading was 5.0 g, the reaction temperature was 460℃, the feed oil was straight-run light diesel oil with a distillation range of 235-337℃, and the product composition was analyzed by gas chromatography. The micro-reaction activity of the light oil was calculated based on the product composition.

[0146] The ratio of Brønsted acid to Lewis acid was determined as follows: the contents of the Brønsted acid centers and Lewis acid centers were obtained by pyridine infrared spectroscopy.

[0147] The micro-reaction activity and stability of the catalytic cracking additive were evaluated as follows: The catalytic cracking additive was pre-treated with hydrothermal heat 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 3, and the reaction temperature and additive-to-oil weight ratio are shown in Table 4.

[0148] Conversion rate (%) = Gasoline yield (%) + Liquefied petroleum gas yield (%) + Dry gas yield (%) + Coke yield (%);

[0149] Coke selectivity (%) = Coke yield (%) / Conversion rate (%) × 100%;

[0150] The average particle size of the additive microspheres was measured and calculated using microscopy. The elemental distribution in the additive was determined using SEM-EDS (scanning electron microscopy combined with energy dispersive spectroscopy).

[0151] Unless otherwise specified herein, the abbreviations and other parameters used in the following examples have conventional definitions in the art and are determined by conventional methods in the art. For example, the abbreviation "LCO" stands for "catalytic cracking cycle oil". These will not be repeated here.

[0152] The following Examples 1-7 and Comparative Examples 1-6 are used to illustrate the preparation and properties of the first series of catalytic cracking aids according to the present invention.

[0153] Example 1

[0154] (1) Add 1000g of aluminum sol and 190g of kaolin to 200g of deionized water and mix well. Then add hydrochloric acid to the obtained slurry to adjust the pH of the slurry to 3. Add 550g of water glass solution and stir for 2 hours to obtain a mixed gel with a solid content of 25.4% by weight. Add 27.1g of lanthanum chloride (LaCl3·6H2O) to the mixed gel and stir for 0.5 hours to obtain a mixed slurry.

[0155] (2) Ammonia was added to the mixed slurry to adjust its pH to 11.5. After aging at 80°C for 6 hours, a stabilized mixed gel was obtained.

[0156] (3) The stabilized mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0157] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.05:10 for ammonium ion exchange, stirred at 60°C for 30 minutes, filtered and repeated three times.

[0158] (5) The ammonium ion-exchanged auxiliary microspheres, deionized water and 27.8 g of magnesium nitrate were mixed at 60 °C and stirred for 30 minutes at a mass ratio of 1:0.025:6 for the auxiliary microspheres:MgO:water to ensure that almost all magnesium ions in the solution were loaded on the auxiliary microspheres. It was measured that there were almost no magnesium ions in the aqueous phase. The mixture was filtered. The resulting filter cake was dried at 120 °C for 8 hours and calcined at 600 °C for 1 hour to obtain catalytic cracking auxiliary C1 (its composition and properties are shown in Table 1). Through analysis, magnesium was mainly loaded on the surface of the auxiliary microspheres and lanthanum was uniformly distributed in the auxiliary microspheres.

[0159] (6) The catalytic cracking aid C1 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed uniformly at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0160] The pore distribution of the catalytic cracking aid C1 prepared in Example 1 is shown in Figure 1.

[0161] Example 2

[0162] (1) Add 2465 g of aluminum sulfate solution and 272 g of kaolin to 200 g of deionized water and mix well. Then add sulfuric acid to the obtained slurry to adjust the pH of the slurry to 1.5. Then add 500 g of water glass solution and stir for 3 hours to obtain a mixed gel with a solid content of 14.5% by weight. Add 10.8 g of cerium chloride (CeCl3·6H2O) to the mixed gel and stir for 1 hour to obtain a mixed slurry.

[0163] (2) Ammonia water was added to the obtained slurry to adjust the pH of the slurry to 10.5, and the stabilized mixed gel was obtained after aging treatment at 60°C for 8 hours.

[0164] (3) The stabilized mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0165] (4) The catalytic cracking additive microspheres, ammonium sulfate and water are mixed in a mass ratio of 1:0.2:8 for ammonium ion exchange. The mixture is stirred at 60°C for 30 minutes, filtered and repeated once.

[0166] (5) The ammonium ion-exchanged auxiliary microspheres, deionized water, and 30.8 g of magnesium sulfate (MgSO4·7H2O) were mixed and stirred at room temperature for 60 minutes at a mass ratio of 1:0.01:3 for the auxiliary microspheres:MgO:water to load magnesium ions on the surface of the auxiliary microspheres. It was measured that there were almost no magnesium ions in the aqueous phase. The mixture was filtered. The resulting filter cake was dried at 120°C for 24 hours and calcined at 500°C for 1.5 hours to obtain catalytic cracking auxiliary C2. Analysis showed that magnesium was basically loaded on the surface of the auxiliary microspheres.

[0167] (6) The catalytic cracking additive C2 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0168] Example 3

[0169] (1) Add 385 g of boehmite and 76 g of kaolin to 500 g of deionized water and mix well. Add hydrochloric acid to adjust the pH of the slurry to 2.5 and stir for 3 hours. Then add 567 g of alkaline silica sol and stir for 5 hours to obtain a mixed gel with a solid content of 32% by weight. Add 34.4 g of zirconium nitrate (Zr(NO3)4·5H2O) to the mixed gel and stir for 1 hour to obtain a mixed slurry.

[0170] (2) Ammonia water was added to the obtained slurry to adjust the pH of the slurry to 11.5, and the slurry was aged at room temperature for 5 hours to obtain a stabilized mixed gel;

[0171] (3) The stabilized mixed gel obtained in step (2) is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0172] (4) The catalytic cracking additive microspheres, ammonium sulfate and water are mixed in a mass ratio of 1:0.3:10 for ammonium ion exchange. The mixture is stirred at 80°C for 30 minutes, filtered and repeated once.

[0173] (5) 18.6 g of diammonium hydrogen phosphate was dissolved in 300 g of deionized water to prepare an impregnation solution. The ammonium ion-exchanged auxiliary microspheres and the impregnation solution were mixed at a mass ratio of 1:0.02 of auxiliary microspheres:P2O5 and kept at room temperature for 12 hours to load phosphorus onto the auxiliary microspheres. After drying at 100 °C for 24 hours and calcining at 450 °C for 2 hours, catalytic cracking auxiliary C3 was obtained. Analysis showed that phosphorus was mainly loaded on the surface of the auxiliary microspheres and a small amount was loaded in the pores of the surface layer with a thickness of less than 1 micrometer.

[0174] (6) The catalytic cracking additive C3 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0175] Example 4

[0176] (1) Add 5211 g of aluminum sulfate solution and 63 g of kaolin to 200 g of deionized water and mix well. Then add sulfuric acid to the obtained slurry to adjust the pH of the slurry to 3. Then add 150 g of alkaline silica sol and stir for 3 hours to obtain a mixed gel with a solid content of 8.8% by weight. Add 11.9 g of titanium tetrachloride to the mixed gel and stir for 1 hour to obtain a mixed slurry.

[0177] (2) Ammonia water was added to the obtained slurry to adjust the pH of the slurry to 9.5, and the slurry was aged at room temperature for 8 hours to obtain a stabilized mixed gel;

[0178] (3) The stabilized mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0179] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.2:20 for ammonium ion exchange, stirred at 80°C for 30 minutes, filtered and repeated twice.

[0180] (5) The ammonium ion-exchanged auxiliary microspheres, deionized water, and 55.8 g of diammonium hydrogen phosphate were mixed and stirred at room temperature for 60 minutes to load phosphorus onto the auxiliary microspheres according to the mass ratio of auxiliary microspheres:P2O5:water of 1:0.06:10. Analysis showed that almost no phosphorus was present in the aqueous phase. The mixture was then filtered. The resulting filter cake was dried at 100°C for 24 hours and calcined at 550°C for 2 hours to obtain catalytic cracking auxiliary C4. Analysis showed that phosphorus was essentially loaded onto the surface of the auxiliary microspheres.

[0181] (6) The catalytic cracking additive C4 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0182] Example 5

[0183] (1) Add 1201 g of aluminum isopropoxide and 114 g of kaolin to 500 g of deionized water and mix well. Add nitric acid to adjust the pH of the slurry to 2 and stir for 3 hours. Then add 375 g of water glass solution and stir for 2 hours to obtain a mixed gel with a solid content of 22% by weight. Add 34 g of yttrium nitrate (Y(NO3)3·6H2O) to the mixed gel and stir for 1 hour to obtain a mixed slurry.

[0184] (2) Ammonia was added to the obtained slurry to adjust the pH of the slurry to 11.5, and the slurry was aged at 60°C for 8 hours to obtain a stabilized mixed gel.

[0185] (3) The stabilized mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0186] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.05:10 for ammonium ion exchange, stirred at 65°C for 30 minutes, filtered and repeated three times.

[0187] (5) The ammonium ion-exchanged auxiliary microspheres, deionized water, 30.8 g of magnesium sulfate and 37.2 g of diammonium hydrogen phosphate were mixed and stirred at room temperature for 60 minutes according to the mass ratio of auxiliary microspheres:MgO:P2O5:water of 1:0.01:0.04:5 to load magnesium and phosphorus elements on the auxiliary microspheres. The analysis showed that there were almost no magnesium ions and phosphorus elements in the aqueous phase. The mixture was filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 500°C for 2 hours to obtain catalytic cracking auxiliary C5. The analysis showed that phosphorus and magnesium elements were mainly loaded on the surface of the auxiliary microspheres.

[0188] (6) The catalytic cracking additive C5 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0189] Example 6

[0190] (1) Add 1795 g of aluminum sol and 89 g of kaolin to 200 g of deionized water and mix well. Then add hydrochloric acid to the obtained slurry to adjust the pH of the slurry to 3.5. Then add 150 g of water glass solution and stir for 2 hours to obtain a mixed gel with a solid content of 22% by weight. Add 5.4 g of lanthanum chloride (LaCl3·6H2O) to the mixed gel and stir for 0.5 hours to obtain a mixed slurry.

[0191] (2) Ammonia water was added to the obtained slurry to adjust the pH of the slurry to 9, and the slurry was aged at 80°C for 6 hours to obtain a stabilized mixed gel.

[0192] (3) The stabilized mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0193] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.1:10 for ammonium ion exchange. The mixture was stirred at 60°C for 30 minutes, filtered and repeated twice.

[0194] (5) The ammonium ion-exchanged auxiliary microspheres, deionized water, and 9.3 g of magnesium nitrate (Mg(NO3)2) were mixed at 60 °C and stirred for 30 minutes to load magnesium onto the auxiliary microspheres at a mass ratio of 1:0.005:6 for the auxiliary microspheres:MgO:water. Analysis showed that the aqueous phase contained almost no magnesium ions. The mixture was filtered. The resulting filter cake was dried at 120 °C for 12 hours and calcined at 500 °C for 2 hours to obtain catalytic cracking auxiliary C6 (its composition and properties are shown in Table 1). Analysis showed that magnesium was mainly loaded on the surface of the auxiliary microspheres.

[0195] (6) The catalytic cracking additive C6 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0196] Example 7

[0197] (1) Add 1000g of aluminum sol and 190g of kaolin to 200g of deionized water and mix well. Then add 27.1g of lanthanum chloride (LaCl3.6H2O), stir for 0.5 hours, add hydrochloric acid to the obtained slurry to adjust the pH of the slurry to 3, and then add 550g of water glass solution. Stir for 2 hours to obtain a mixed gel with a solid content of 24.4% by weight.

[0198] (2) Ammonia was added to the obtained mixed gel to adjust the pH of the slurry to 11.5, and the mixture was aged at 80°C for 6 hours to obtain a stabilized mixed gel.

[0199] (3) The stabilized mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0200] (4) The above-mentioned auxiliary microspheres, deionized water and 27.8 g of magnesium nitrate were mixed at 60°C and stirred for 30 minutes according to the mass ratio of auxiliary microspheres:MgO:water of 1:0.025:6 to load magnesium ions onto the auxiliary microspheres. The analysis showed that there were almost no magnesium ions in the aqueous phase. The mixture was filtered. The resulting filter cake was dried at 120°C for 8 hours and calcined at 600°C for 1 hour.

[0201] (5) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.05:10 for ammonium ion exchange. The mixture was stirred at 60°C for 30 minutes, filtered and repeated three times. The resulting filter cake was dried at 120°C for 8 hours to obtain catalytic cracking additive C7 (its composition and properties are shown in Table 1). Analysis showed that magnesium was mainly loaded on the surface of the additive microspheres and lanthanum was uniformly distributed in the additive microspheres.

[0202] (6) The catalytic cracking additive C7 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed at a mass ratio of 1:9 to obtain the catalytic cracking composition.

[0203] Comparative Example 1

[0204] The comparative example prepared the catalytic cracking composition according to the method of Example 1, but with the difference that the aging step (2) was not performed, i.e.:

[0205] [Correction 18.11.2025 according to Rule 91] (1) Add 1000g of aluminum sol and 206g of kaolin to 200g of deionized water and mix evenly. Then add hydrochloric acid to the obtained slurry to adjust the pH of the slurry to 3. Then add 550g of water glass solution and stir for 2 hours to obtain a mixed gel with a solid content of 25.5% by weight.

[0206] (3) The mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0207] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.05:10 for ammonium ion exchange, stirred at 60°C for 30 minutes, filtered and repeated three times.

[0208] (5) The ammonium ion-exchanged auxiliary microspheres, deionized water and 27.8 g of magnesium nitrate were mixed at 60 °C and stirred for 30 minutes at a mass ratio of 1:0.025:6 for the auxiliary microspheres:MgO:water to ensure that almost all magnesium ions in the solution were loaded on the auxiliary microspheres. It was measured that there were almost no magnesium ions in the aqueous phase. The mixture was filtered. The resulting filter cake was dried at 120 °C for 8 hours and calcined at 600 °C for 1 hour to obtain catalytic cracking auxiliary DC1 (its composition and properties are shown in Table 1).

[0209] (6) The catalytic cracking additive DC1 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0210] The pore distribution of the catalytic cracking promoter DC1 prepared from Comparative Example 1 is shown in Figure 1.

[0211] Comparative Example 2

[0212] The comparative example prepared a catalytic cracking composition according to the method described in Example 1, except that no activity-regulating element was loaded in step (5). Catalytic cracking promoter DC2 was obtained (its composition and properties are shown in Table 1).

[0213] Comparative Example 3

[0214] Catalytic cracking aid DC3 was prepared according to the method of Example 1 in CN114272919A.

[0215] Comparative Example 4

[0216] The comparative example prepared a catalytic cracking composition according to the operation method of Example 1, but with the difference that both the stabilizing element source and the activity regulating element source were added in step (1); the preparation was carried out as follows:

[0217] (1) Add 1000g of aluminum sol and 206g of kaolin to 200g of deionized water and mix evenly. Then add hydrochloric acid to the obtained slurry to adjust the pH of the slurry to 3. Add 550g of water glass solution and stir for 2 hours to obtain a mixed gel with a solid content of 25.5% by weight. Add 21.7g of lanthanum chloride (LaCl3.6H2O) and 27.8g of magnesium nitrate to the silica-alumina gel and stir for 0.5 hours to obtain a mixed slurry.

[0218] (2) Ammonia was added to the mixed slurry to adjust its pH to 11.5. After aging at 80°C for 6 hours, a stabilized mixed gel was obtained.

[0219] (3) The stabilized mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0220] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.05:10 for ammonium ion exchange, stirred at 60°C for 30 minutes, filtered and repeated three times.

[0221] (5) The filter cake obtained in step (4) was dried at 120°C for 8 hours and calcined at 600°C for 1 hour to obtain catalytic cracking additive DC4 (its composition and properties are shown in Table 1). Analysis showed that magnesium and lanthanum elements were primarily distributed within the obtained additive microspheres.

[0222] (6) The catalytic cracking additive DC4 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed uniformly at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0223] Comparative Example 5

[0224] The comparative example prepared a catalytic cracking composition according to the operation method of Example 1, except that both the stabilizing element source and the activity regulating element source were loaded in step (5); the preparation was carried out as follows:

[0225] (1) Add 1000g of aluminum sol and 190g of kaolin to 200g of deionized water and mix them evenly. Then add hydrochloric acid to the obtained slurry to adjust the pH of the slurry to 3. Add 550g of water glass solution to it and stir for 2 hours to obtain a mixed gel with a solid content of 25.4% by weight.

[0226] (2) Ammonia was added to the mixed gel to adjust its pH to 11.5. After aging at 80°C for 6 hours, a stabilized mixed gel was obtained.

[0227] (3) The stabilized mixed gel is spray-dried to form a microsphere with an average particle size of about 75 micrometers.

[0228] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.05:10 for ammonium ion exchange, stirred at 60°C for 30 minutes, filtered and repeated three times.

[0229] (5) The ammonium ion-exchanged auxiliary microspheres, deionized water, and 27.8 g of magnesium nitrate were uniformly mixed at 60 °C according to a mass ratio of auxiliary microspheres:MgO:water of 1:0.025:6. Then, 27.1 g of lanthanum chloride (LaCl3·6H2O) was added and stirred for 12 hours to impregnate almost all magnesium and lanthanum ions in the solution onto the auxiliary microspheres. The mixture was then filtered. The resulting filter cake was dried at 120 °C for 8 hours and calcined at 600 °C for 1 hour to obtain catalytic cracking auxiliary DC5 (its composition and properties are shown in Table 1). Analysis showed that magnesium and lanthanum elements were basically loaded on the surface of the obtained auxiliary microspheres and a small amount were loaded in the pores of the surface layer.

[0230] (6) The catalytic cracking additive DC5 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 2) are mixed uniformly at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0231] Comparative Example 6

[0232] The comparative example prepared the catalytic cracking composition according to the operation method of Example 1, but with the difference that the amount of aluminum sol and water glass solution added in step (1) was changed so that the content ratio of silicon species to aluminum species in the matrix, based on the SiO2 / Al2O3 molar ratio, was about 3.4.

[0233] Specifically, step (1) is as follows: 500g of aluminum sol and 190g of kaolin are added to 200g of deionized water and mixed evenly. Then, hydrochloric acid is added to the obtained slurry to adjust the pH of the slurry to 3. Then, 1100g of water glass solution is added to it and stirred for 2 hours to obtain a mixed gel with a solid content of 25.0% by weight.

[0234] The final catalytic cracking additive DC6 was obtained (its composition and properties are shown in Table 1).

[0235] Table 1. Composition and properties of catalytic cracking additives

[0236] Table 1 (continued)

[0237] As can be seen from the results in Table 1, compared with the comparative catalytic cracking promoters, the first series of catalytic cracking promoters according to the present invention have a SiO2 / Al2O3 molar ratio of less than 2 in the matrix, and contain specific stabilizing elements in the matrix and specific activity regulating elements in the microsphere surface layer. Therefore, they have significantly higher total pore volume, 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, significantly higher Brønsted acid content, and excellent activity stability.

[0238] 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 additive microspheres of the present invention further facilitates obtaining high strength, large total pore volume, pore distribution more suitable for catalytic cracking reactions, and high activity stability of the additive.

[0239] Test case

[0240] The catalytic cracking compositions prepared in Examples 1-8 and Comparative Examples 1-6 were subjected to aging treatment at 800°C and 100% steam for 12 hours in a fixed-bed aging unit, and then evaluated in an ACE unit. The properties of the feedstock used for evaluation are shown in Table 3, and the test results of reaction temperature, catalyst-to-oil weight ratio, and catalytic performance of the catalytic cracking compositions are shown in Table 4.

[0241] Conversion rate (%) = Gasoline yield (%) + Liquefied petroleum gas yield (%) + Dry gas yield (%) + Coke yield (%);

[0242] Coke selectivity (%) = Coke yield (%) / Conversion rate (%) × 100%.

[0243] Table 2. Properties of Industrial Agents

[0244] Table 3. Properties of Crude Oil

[0245] Table 4. Catalytic performance of catalytic cracking compositions

[0246] Table 4 (continued)

[0247] As can be seen from the test results of the catalytic performance in Table 4, the catalytic cracking composition according to the present invention has stronger heavy oil conversion performance compared with the comparative catalytic cracking composition. When the catalytic cracking composition according to the present invention is applied to heavy oil catalytic cracking, the condensation of heavy oil macromolecules to form coke and over-cracking are avoided, and the selectivity of light oil is significantly improved and the selectivity of coke is reduced.

[0248] Examples 8-15 and Comparative Examples 7-11 below are used to illustrate the preparation and properties of the second series of catalytic cracking aids of the present invention.

[0249] Example 8

[0250] (1) Add 909g of aluminum sol and 190g of kaolin to 300g of deionized water and mix evenly. Then add hydrochloric acid to the obtained slurry to adjust the pH of the slurry to 2.5. Stir for 1 hour, then add 550g of water glass solution and stir for 2 hours. Then add 20g of magnesium oxide and stir for 1 hour to obtain a silica-alumina-magnesium gel with a solid content of 24.4% by weight.

[0251] (2) Ammonia was added to the obtained silica-alumina-magnesium gel to adjust the pH of the gel to 11.5, and after aging at room temperature for 4 hours, the stabilized silica-alumina-magnesium gel was obtained.

[0252] (3) The stabilized silica-alumina-magnesium gel is spray-dried and shaped, wherein the tail gas temperature of the spray drying is 170°C, and it is calcined at 200°C for 1 hour to obtain additive microspheres with an average particle size of about 75 micrometers.

[0253] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.15:10 (on a dry basis): ammonium sulfate: water to carry out ammonium ion exchange. The mixture was stirred at 80°C for 30 minutes, filtered and repeated twice.

[0254] (5) The ammonium-exchanged additive microspheres, deionized water, and 37.2 g of diammonium hydrogen phosphate were mixed at a mass ratio of 1:0.04:8 (on a dry basis) to P2O5 to water. The mixture was stirred at 60°C for 30 minutes to load phosphorus onto the additive microspheres. After confirming that the aqueous phase contained virtually no phosphorus, the mixture was filtered. The resulting filter cake was dried at 120°C for 12 hours and calcined at 500°C for 1 hour to obtain catalytic cracking additive C8 (its composition and properties are shown in Table 5). Analysis showed that magnesium was uniformly distributed in the additive microspheres, while phosphorus was mainly loaded on the surface of the additive microspheres.

[0255] (6) The catalytic cracking additive C8 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 6) are mixed uniformly at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0256] Example 9

[0257] (1) Mix 2676 g of aluminum sulfate solution and 177 g of kaolin evenly, then add hydrochloric acid to the obtained slurry to adjust the pH of the slurry to 2.5, stir for 1 hour, then add 763 g of water glass solution, stir for 2 hours, then add 40.2 g of magnesium acetate, stir for 0.5 hours to obtain a silica-alumina-magnesium gel with a solid content of 13% by weight.

[0258] (2) Add ammonia to the obtained silica-alumina-magnesium gel to adjust the pH of the slurry to 11, and age it at 60°C for 4 hours to obtain the stabilized silica-alumina gel.

[0259] (3) The stabilized silica-alumina gel is spray-dried and shaped, wherein the exhaust gas temperature of the spray drying is 170°C, and it is calcined at 250°C for 1 hour to obtain additive microspheres with an average particle size of about 75 micrometers.

[0260] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.2:10 (on a dry basis): ammonium sulfate: water to carry out ammonium ion exchange. The mixture was stirred at room temperature for 30 minutes, filtered and repeated once.

[0261] (5) According to the mass ratio of 1:0.02 of auxiliary microspheres (on a dry basis):B2O3, 17.8g of boric acid was dissolved in 300g of deionized water to prepare an impregnation solution. The impregnation solution was then contacted with the ion-exchanged auxiliary microspheres and kept at room temperature for 12 hours to allow boron to be loaded onto the auxiliary microspheres. The microspheres were dried at 100℃ for 12 hours and calcined at 450℃ for 2 hours to obtain catalytic cracking auxiliary C9 (its composition and physical properties are shown in Table 5). Through analysis, magnesium was uniformly distributed in the auxiliary microspheres, while boron was mainly loaded on the surface of the auxiliary microspheres and a small amount was loaded in the pores of the surface layer.

[0262] (6) The catalytic cracking additive C9 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 6) are mixed evenly at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0263] Example 10

[0264] (1) Add 285g of kaolin and 269g of boehmite to 500g of deionized water and mix them evenly. Then add nitric acid to the slurry to adjust the pH of the slurry to 2. Stir for 3 hours, then add 269g of alkaline silica sol and stir for 1 hour. Then add 30.8g of magnesium sulfate and stir for 2 hours to obtain a silica-alumina-magnesium gel with a solid content of 35% by weight.

[0265] (2) Add ammonia to the obtained silica-alumina-magnesium gel to adjust the pH of the slurry to 9.8, and age it at 60°C for 8 hours to obtain stabilized silica-alumina gel.

[0266] (3) The stabilized silica-alumina gel is spray-dried and shaped, wherein the exhaust gas temperature of the spray drying is 190°C, and it is calcined at 300°C for 1 hour to obtain additive microspheres with an average particle size of about 75 micrometers.

[0267] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.3:15 (on a dry basis): ammonium sulfate: water to carry out ammonium ion exchange. The mixture was stirred at 80°C for 30 minutes, filtered, and repeated once.

[0268] (5) At a mass ratio of 1:0.02:10 (on a dry basis) of auxiliary microspheres:La2O3:water, ammonium ion-exchanged auxiliary microspheres, deionized water, and 21.7 g of lanthanum chloride (LaCl3·6H2O) were mixed and stirred at room temperature for 60 minutes to ensure that almost all lanthanum ions were loaded onto the auxiliary microspheres. The mixture was then filtered. Next, at a mass ratio of 1:0.01 (on a dry basis) of auxiliary microspheres:P2O5, 9.3 g of phosphoric acid was added. Diammonium hydrogen was dissolved in 200g of deionized water to prepare an impregnation solution. The resulting impregnation solution was then contacted with the lanthanum-loaded auxiliary microspheres described above and kept at room temperature for 12 hours to allow phosphorus to be loaded onto the auxiliary microspheres. The microspheres were then dried at 120°C and calcined at 500°C for 2 hours to obtain catalytic cracking auxiliary C10 (its composition and physical properties are shown in Table 5). Analysis showed that magnesium was uniformly distributed in the auxiliary microspheres, while lanthanum and phosphorus were mainly loaded on the surface of the auxiliary microspheres.

[0269] (6) The catalytic cracking additive C10 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 6) are mixed at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0270] Example 11

[0271] (1) Mix 5070 g of aluminum sulfate solution and 70 g of kaolin evenly and stir for 0.5 hours. Then add sulfuric acid to the obtained slurry to adjust the pH of the slurry to 3.8. Then add 133 g of alkaline silica sol and stir for 2 hours. Then add 61.5 g of magnesium sulfate and stir for 2 hours to obtain a silica-alumina-magnesium gel with a solid content of 8% by weight.

[0272] (2) Ammonia was added to the obtained silica-alumina-magnesium gel slurry to adjust the pH of the slurry to 11.5, and the slurry was aged at 65°C for 8 hours to obtain the stabilized silica-alumina gel.

[0273] (3) The stabilized silica-alumina gel is spray-dried and shaped, wherein the tail gas temperature of the spray drying is 165°C, and it is calcined at 350°C for 1 hour to obtain additive microspheres with an average particle size of about 75 micrometers.

[0274] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.2:20 (on a dry basis): ammonium sulfate: water to carry out ammonium ion exchange. The mixture was stirred at 80°C for 30 minutes, filtered and repeated twice.

[0275] (5) According to the mass ratio of 1:0.06:0.01:6 (on a dry basis):P2O5:CeO2:water, the ammonium ion-exchanged auxiliary microspheres, deionized water, 55.8 g of diammonium hydrogen phosphate and 10.8 g of cerium chloride (CeCl3·7H2O) were mixed and stirred at room temperature for 60 minutes to load almost all phosphorus and cerium elements onto the auxiliary microspheres; filtered; the resulting filter cake was dried at 120 °C for 12 hours and calcined at 500 °C for 1 hour to obtain catalytic cracking auxiliary C11 (its composition and physical properties are shown in Table 5); by analysis, magnesium elements were uniformly distributed in the auxiliary microspheres, while cerium and phosphorus elements were mainly loaded on the surface of the auxiliary microspheres;

[0276] (4) The catalytic cracking aid C11 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 6) are mixed uniformly at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0277] Example 12

[0278] (1) Add 1101 g of aluminum isopropoxide to 500 g of deionized water, then add acetic acid to the obtained slurry to adjust the pH of the slurry to 2.5, stir for 3 hours, then add 127 g of kaolin, stir for 1 hour, then add 450 g of water glass solution, stir for 3 hours, then add 92.7 g of magnesium nitrate, stir for 1 hour, and obtain a silica-alumina-magnesium gel with a solid content of 21% by weight.

[0279] (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, the stabilized silica-alumina gel was obtained.

[0280] (3) The stabilized silica-alumina gel is spray-dried and shaped, wherein the exhaust gas temperature of the spray drying is 160°C, and it is calcined at 200°C for 1 hour to obtain additive microspheres with an average particle size of about 75 micrometers.

[0281] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.05:12 (on a dry basis): ammonium sulfate: water to carry out ammonium ion exchange. The mixture was stirred at 65°C for 30 minutes, filtered and repeated three times.

[0282] (5) 16.2 g of ammonium dihydrogen phosphate was dissolved in 400 g of deionized water to prepare an impregnation solution at a mass ratio of 1:0.02 (on a dry basis) of additive microspheres to P2O5. The resulting impregnation solution was then contacted with the additive microspheres that had undergone ammonium ion exchange and kept at room temperature for 24 hours to ensure that almost all phosphorus was loaded onto the additive microspheres. The microspheres were then dried at 120 °C for 12 hours and calcined at 500 °C for 2 hours to obtain catalytic cracking additive C12 (its composition and properties are shown in Table 5). Analysis showed that magnesium was uniformly distributed within the additive microspheres, while phosphorus was mainly loaded on the surface of the microspheres and a small amount was loaded in the pores of the surface layer.

[0283] (6) The catalytic cracking additive C12 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 6) are mixed uniformly at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0284] Example 13

[0285] (1) Add 727 g of aluminum sol and 222 g of kaolin to 300 g of deionized water and mix them evenly. Stir for 0.5 hours. Then add hydrochloric acid to the slurry to adjust the pH of the slurry to 3. Then add 800 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 25% by weight.

[0286] (2) Add ammonia to the obtained silica-alumina-magnesium gel to adjust the pH of the gel to 11, and age it at 60°C for 6 hours to obtain the stabilized silica-alumina gel.

[0287] (3) The stabilized silica-alumina gel is spray-dried and shaped, wherein the tail gas temperature of the spray drying is 155°C, and it is calcined at 200°C for 1.5 hours to obtain additive microspheres with an average particle size of about 75 micrometers.

[0288] (4) The catalytic cracking additive microspheres, ammonium sulfate and water were mixed at a mass ratio of 1:0.15:10 (on a dry basis): ammonium sulfate: water to carry out ammonium ion exchange. The mixture was stirred at 60°C for 30 minutes, filtered and repeated twice.

[0289] (5) At a mass ratio of 1:0.005:5 (dry basis) of additive microspheres:P2O5:water, ammonium ion-exchanged additive microspheres, deionized water, and 4.6 g of diammonium hydrogen phosphate were mixed and stirred at 60 °C for 30 minutes to ensure that almost all phosphorus was loaded onto the additive microspheres; the mixture was filtered; the resulting filter cake was dried at 120 °C for 12 hours and calcined at 500 °C for 2 hours to obtain catalytic cracking additive C13 (its composition and properties are shown in Table 5). Analysis showed that magnesium was uniformly distributed in the additive microspheres, while phosphorus was mainly loaded on the surface of the additive microspheres.

[0290] (4) The catalytic cracking additive C13 and the catalytic cracking catalyst (industrial agent, whose main properties are listed in Table 6) are mixed at a mass ratio of 3:7 to obtain the catalytic cracking composition.

[0291] Example 14

[0292] This embodiment prepared the catalytic cracking composition according to the method of Example 8, but with the difference that in step (1), the amount of kaolin was increased from 190 g to 211 g, and the amount of magnesium oxide was reduced from 20 g to 3 g. Catalytic cracking aid C14 was obtained (its composition and properties are shown in Table 5).

[0293] Example 15

[0294] This embodiment prepared the catalytic cracking composition according to the method of Example 8, but with the difference that in step (1), the amount of kaolin was reduced from 190 g to 158 g; and in step (3), 152.7 g of yttrium nitrate (Y(NO3)3·6H2O) was used instead of 37.2 g of diammonium hydrogen phosphate. Catalytic cracking aid C15 was obtained (its composition and properties are shown in Table 5).

[0295] Comparative Example 7

[0296] The comparative example prepared a catalytic cracking composition according to the method described in Example 8, but instead of performing the aging treatment step (2), the silica-alumina-magnesium gel obtained in step (1) was directly spray-dried and shaped. The final catalytic cracking aid DC7 was obtained (its composition and properties are shown in Table 5).

[0297] Comparative Example 8

[0298] The comparative example prepared a catalytic cracking composition according to the method described in Example 8, but the difference was that in step (5), no activity regulating element was loaded, and the filter cake obtained in step (4) was directly dried at 120°C for 12 hours and calcined at 500°C for 1 hour. Finally, the catalytic cracking aid DC8 was obtained (its composition and properties are shown in Table 5).

[0299] Comparative Example 9

[0300] The comparative example prepared a catalytic cracking composition according to the method described in Example 8, but with the difference that the catalytic cracking aid DC9 (whose composition and properties are shown in Table 5) was prepared according to the method of Example 1 of CN114272919A, and then the catalytic cracking aid C1 was replaced with the catalytic cracking aid DC9 to prepare the catalytic cracking composition.

[0301] Comparative Example 10

[0302] The comparative example prepared a catalytic cracking composition according to the method described in Example 8, but with the difference that the stabilizing element and the activity regulating element were added together in step (1), and the activity regulating element was not loaded in step (5). The final product was additive microspheres DC10 (the composition and properties of which are shown in Table 5).

[0303] Comparative Example 11

[0304] The comparative example prepared the catalytic cracking composition according to the operation method of Example 8, but with the difference that the amount of aluminum sol and water glass solution added in step (1) was changed so that the content ratio of silicon to aluminum in terms of SiO2 / Al2O3 molar ratio was about 3.6. The final catalytic cracking aid DC11 was obtained.

[0305] The composition and properties of the catalytic cracking aid DC11 prepared in this comparative example are shown in Table 5.

[0306] Table 5. Composition and properties of catalytic cracking additives

[0307] Table 5 (continued)

[0308] As can be seen from the results in Table 5, compared with the comparative catalytic cracking additives, the first series of catalytic cracking additives according to the present invention have a matrix with a SiO2 / Al2O3 molar ratio of less than 2, and contain stabilizing elements in the microspheres and loading activity regulating elements on the surface of the additive microspheres. Therefore, they have a significantly larger total pore volume, a 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), and a higher alkali center content, while also exhibiting excellent activity and stability. After treatment at 800°C and 100% water vapor for 17 hours, the micro-reaction activity retention reaches more than 60%, significantly higher than the micro-reaction activity retention of the catalytic cracking additives in the comparative examples.

[0309] Furthermore, a comparison of the results of Examples 8 and 9 with those of Comparative Example 10 shows that the specific distribution of stabilizing elements and activity regulating elements in the microspheres of the present invention is more conducive to the present invention obtaining a large total pore volume, a pore distribution suitable for catalytic cracking reactions, high catalytic activity, and high stability.

[0310] Test case

[0311] The catalytic cracking compositions prepared by the embodiments and comparative examples of the present invention were subjected to aging treatment at 800°C and 100% steam for 12 hours in a fixed-bed aging unit, and then evaluated in an ACE unit. The properties of the feedstock used for evaluation are shown in Table 6, and the reaction temperature, catalyst-to-oil weight ratio and test results are shown in Table 7.

[0312] Conversion rate (%) = Gasoline yield (%) + Liquefied petroleum gas yield (%) + Dry gas yield (%) + Coke yield (%);

[0313] Coke selectivity (%) = Coke yield (%) / Conversion rate (%) × 100%.

[0314] Table 6. Properties of Industrial Agents

[0315] Table 7. Properties of Crude Oil

[0316] Table 8. Catalytic performance of catalytic cracking compositions

[0317] Table 8 (continued)

[0318] As can be seen from the test results of catalytic performance in Table 8, compared with the comparative catalytic cracking composition, when the catalytic cracking composition according to the present invention is applied to the heavy oil catalytic cracking method, a significantly higher heavy oil conversion rate is allowed, the ratio of diesel to heavy oil yield is improved, and while increasing the yield of light oil, the yield and selectivity of coke are greatly reduced, resulting in a superior catalytic effect.

[0319] The above embodiments describe in detail the preferred embodiments of the present invention; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention.

[0320] 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.

[0321] 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 aid, characterized in that, Based on the total dry weight of the catalytic cracking promoter, the catalytic cracking promoter comprises: 5-50 wt% clay on a dry basis, 5-40 wt% silicon species (SiO2), 30-80 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, Group IIIB, and Group IVB elements.

2. The catalytic cracking aid according to claim 1, characterized in that, Based on the dry weight of the catalytic cracking promoter, the catalytic cracking promoter comprises: 10-45 wt% clay on a dry basis, 8-35 wt% silicon species (SiO2), 35-75 wt% aluminum species (Al2O3), 0.5-5 wt%, preferably 1-4 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 promoter, the catalytic cracking promoter comprises: 10-45 wt% clay on a dry basis, 8-35 wt% silicon species (SiO2), 35-75 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 50-85% by weight.

3. The catalytic cracking aid according to any one of claims 1-2, characterized in that, The catalytic cracking additive exists in the form of microspheres, with the stabilizing element distributed inside the additive microspheres and the activity regulating element mainly loaded on the surface of the additive microspheres and optionally loaded in small amounts in the pores of the surface layer.

4. The catalytic cracking aid according to any one of claims 1-3, characterized in that, The stabilizing element of the catalytic cracking promoter is selected from at least one of La, Ce, Y, Zr and Ti, the activity regulating element is selected from at least one of Mg and P, and the ratio of the amount of Brønsted acid to Lønsted acid in the catalytic cracking catalyst, as measured by pyridine infrared spectroscopy, is 0.05-0.

5.

5. The catalytic cracking aid according to any one of claims 1-4, characterized in that, The total pore volume of the catalytic cracking aid, as determined by the low-temperature nitrogen adsorption method, is not less than 0.5 mL / g, preferably 0.6-1.5 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, preferably 85%-99%. And / or, the specific surface area of ​​the catalytic cracking aid is 150-350 m². 2 / g, preferably 180-300m 2 / g; And / or, the most probable pore size of the catalytic cracking aid is 10-40 nm, preferably 15-35 nm; And / or, the wear index of the catalytic cracking aid is not higher than 2.6 m% / h, preferably 0.5-2.5 m% / h.

6. The catalytic cracking aid according to any one of claims 1-5, characterized in that, The stabilizing element of the catalytic cracking aid is selected from Mg, and the activity regulating element is selected from at least one of P, B, La, Ce, Y, Zr and Ti. The alkali center content of the catalytic cracking aid, as determined by CO2-TPD, is 0.05-0.5 mmol / g, and / or the micro-reaction activity retention of the catalytic cracking aid after treatment at 800°C and 100% steam for 17 hours is not less than 60%.

7. A catalytic cracking composition, characterized in that, The catalytic cracking composition comprises a catalytic cracking catalyst and a catalytic cracking aid according to any one of claims 1-6.

8. The catalytic cracking composition according to claim 7, characterized in that, The mass ratio of the catalytic cracking catalyst to the catalytic cracking aid is 1:0.05-0.8, preferably 1:0.15-0.

6.

9. The catalytic cracking composition according to any one of claims 7-8, characterized in that, Based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst comprises: 0.1-10% by weight of rare earth metal elements in oxide form, 40-60% by weight of aluminum species in Al2O3 form and 20-50% by weight of silicon species in SiO2 form.

10. A method for preparing a catalytic cracking aid according to any one of claims 1-6, characterized in that, The method includes the following steps: (1) In the presence of a solvent, clay, silicon source, aluminum source, stabilizing element source and optional acid are uniformly mixed to obtain a mixed gel; (2) The obtained mixed gel is subjected to aging treatment to obtain a stabilized mixed gel; (3) The obtained stabilized mixed gel is spray-dried and shaped, and optionally calcined to obtain additive microspheres; (4) The adjuvant microspheres are subjected to ammonium ion exchange, and then... (5) Loading an activity regulating element onto an ammonium ion-exchanged additive microsphere, and then optionally filtering, drying and calcining the additive microsphere loaded with the activity regulating element; to obtain a catalytic cracking additive. The amount of clay, silicon source, aluminum source, stabilizing element source, and activity regulating element source added is such that the obtained catalytic cracking aid comprises, based on the dry weight of the catalytic cracking aid: 5-50% by weight of clay on a dry basis, 5-40% by weight of silicon species calculated as SiO2, 30-80% by weight of aluminum species calculated as Al2O3, 0.5-15% by weight, preferably 0.5-5% by weight of stabilizing element calculated as oxide, and 0.5-10% by weight of activity regulating element calculated as oxide; the content ratio of silicon species and aluminum species, calculated as SiO2 / Al2O3 molar ratio, is 0.05-2, preferably 0.2-1.

5.

11. The method according to claim 10, characterized in that, In step (1), the mixed gel is prepared by the following preparation method: first, in the presence of a solvent, a mixed slurry of clay and aluminum source is uniformly mixed with acid, then a silicon source is added and uniformly mixed, and then a stabilizing element source is added and uniformly mixed to obtain a mixed gel; preferably, the solid content of the mixed gel is 5-40% by weight, preferably 5-35% by weight; Wherein, the source of the stabilizing element is a compound containing a stabilizing element, selected from at least one of the nitrate, chloride, sulfate, phosphate, acetate, oxalate, oxide and alkoxide of the stabilizing element, more preferably at least one of nitrate and / or chloride; And / or, 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, aluminum sol and boehmite; And / or, the silicon source is selected from at least one of water glass, alkaline silica sol, acidic silica sol, neutral silica sol, tetraethyl orthosilicate and tetramethoxysilane, preferably at least one of water glass and alkaline silica sol.

12. The method according to claim 11, characterized in that, The amount of acid used is such that the pH of the mixed sol obtained after mixing in step (1) is 1-4; preferably, the acid is at least one of inorganic acid and organic acid, preferably selected from at least one of hydrochloric acid, sulfuric acid, nitric acid, acetic acid and citric acid.

13. The method according to any one of claims 10-12, characterized in that, In step (2), before the aging treatment, the mixed gel is uniformly mixed with an alkali to obtain a mixture with a pH of 9-12, and / or the conditions for the aging treatment 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.

14. The method according to any one of claims 10-13, characterized in that, In step (3), the exhaust gas temperature of the spray drying is 100-300℃, preferably 120-200℃; and / or, the conditions for carrying out the calcination include: a temperature of 300-600℃, a time of 0.5-5 hours, and a heating rate of 2-10℃ / min.

15. The method according to any one of claims 10-14, characterized in that, In step (4), the ammonium ion exchange is performed as follows: the auxiliary microspheres are contacted with the ammonium salt solution for 10-120 minutes at a temperature of 20-100°C, preferably 20-80°C, so that the sodium oxide content on the surface of the auxiliary microspheres after ammonium ion exchange is not higher than 0.3% by weight, preferably 0.05-0.25% by weight; wherein, on a dry basis, the mass ratio of the auxiliary microspheres to the ammonium salt is 1:0.01-0.6, preferably 1:0.02-0.5; And / or, on a dry basis, the mass ratio of the auxiliary microspheres to the solvent is 1:5-20; And / or, 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.

16. The method according to any one of claims 10-15, 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 ammonium ion-exchanged auxiliary microspheres for impregnation and / or ion exchange; wherein the activity regulating element source is a compound containing the activity regulating element, selected from at least one of the nitrate, chloride, sulfate, phosphate, acetate, oxalate and alkoxide of the activity regulating element, such as 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; and / or, the activity regulating element source is mixed and contacted with ammonium ion-exchanged auxiliary microspheres for impregnation and / or ion exchange. The conditions for mixing and contacting the agent microspheres include: a temperature of 20-100℃, preferably 20-80℃; a time of 10-120 minutes; and / or, a mass ratio of the agent microspheres and solvent on a dry basis of 1:5-15, preferably 1:5-10; and / or, a mass ratio of the agent microspheres and the active regulating element source on a dry basis of 1:0.005-0.1, preferably 1:0.01-0.08; and / or, the conditions for calcination include: a temperature of 400-600℃, preferably 450-550℃; and a time of 0.5-5 hours, preferably 1-3 hours.

17. Use of the catalytic cracking additive according to any one of claims 1-6 or the catalytic cracking composition according to any one of claims 7-9 in a heavy oil catalytic cracking method, wherein the additive is used to reduce the selectivity of coke.

18. A method for catalytic cracking of heavy oil, comprising contacting heavy oil with a catalytic cracking composition according to any one of claims 7-9 to carry out a catalytic cracking reaction.

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