Composite startup catalyst, and preparation method therefor and use thereof

Abstract

The present invention relates to a composite startup catalyst, characterized in that, based on the dry weight of the composite startup catalyst, the composite startup catalyst comprises: 15-95% by weight of a component A catalyst selected from a catalytic pyrolysis or catalytic cracking equilibrium catalyst and / or a treated catalytic pyrolysis or catalytic cracking equilibrium catalyst, wherein the treatment comprises demetallization treatment and / or particle size adjustment treatment; 5-85% by weight of a component B catalyst selected from one or more fresh catalytic pyrolysis catalysts or catalytic cracking catalysts; and optionally a component C catalyst, wherein the component C catalyst contains 2-10% by weight of a modified metal oxide. The present invention also relates to a preparation method for the composite startup catalyst, a use of the composite startup catalyst in startup of a catalytic pyrolysis or catalytic cracking device, and a startup method for a catalytic pyrolysis or catalytic cracking device.

Description

A composite start-up catalyst and its preparation method and application Technical Field

[0001] The present invention belongs to the technical field of catalysts and relates to a composite start-up catalyst, in particular to a composite start-up catalyst for efficient start-up, and a preparation method and application thereof. Background Art

[0002] Light olefins, such as ethylene and propylene, are important basic organic chemical raw materials and are considered the cornerstones of the modern chemical industry. With the growing demand for light olefins and the ever-expanding application areas, the development and research of efficient production methods has become increasingly important. Catalytic cracking is one of the most promising technologies for light olefin production. This technology allows for flexible adjustment of product distribution and, compared to thermal cracking, can lower reaction temperatures and reduce energy consumption.

[0003] A startup catalyst is used when restarting a new unit or an existing unit after a shutdown, such as one for maintenance. To ensure smooth startup of a catalytic cracking unit, the catalyst's activity must be close to the expected activity of the balance agent for the target unit. Its physical properties and catalytic performance must match those of the target unit to ensure stable and safe startup, and a stable product distribution that remains close to the target within a short period of time, guaranteeing economic benefits. In newly built catalytic cracking units, the use of different balance agents can delay the unit reaching design operating conditions due to differences in process, equipment, feedstock, and processing strategies.

[0004] When a new catalytic cracking unit or catalytic cracking unit is put into operation, or when the unit is put into operation after being shut down for maintenance, a start-up catalyst is required. Traditional start-up catalysts for new units generally adopt a balance agent solution, which has many limitations: first, the physical and chemical properties of the balance agents of different units vary significantly due to the properties of the raw materials, actual operating conditions, etc., and are often difficult to use directly. For example, the use of FCC balance agents in DCC units will cause key technical indicators such as low-carbon olefins to fail to reach the design values ​​for a long time; second, the market resources for catalytic cracking balance agents are scarce, and the quality is uneven; third, different process conditions have different requirements for start-up catalysts, which are difficult to match efficiently, seriously affecting the stable operation and economic benefits of the unit. During normal production, when the balance agent is poisoned and needs to be quickly replaced, or when the catalyst and the unit have abnormal leakage, the catalyst needs to be replenished.

[0005] Technologies for producing light olefins by catalytic cracking of heavy oil or high-density heavy oil, such as the RTC process technology, effectively utilize inferior heavy oil to produce propylene and ethylene. However, the existing technology does not have a start-up catalyst specifically for the catalytic cracking of heavy oil or high-density heavy oil.

[0006] Catalytic cracking is an important method for producing gasoline, producing liquefied petroleum gas (LPG), of which propylene is a key chemical feedstock. To increase both propylene and gasoline production, refiners have developed technologies for producing clean gasoline, such as MIP (a novel catalytic cracking process for producing clean gasoline components, Xu Youhao et al., Petroleum Refining and Chemicals, Vol. 32, No. 8, pp. 1-5). Furthermore, a series of MIP technologies have been developed, including MIP-CGP (a MIP Process for Clean Gasoline and Propylene, developed by Sinopec Research Institute of Petroleum Chemicals Co., Ltd. based on a catalytic cracking technology that produces more isoparaffins and produces gasoline that meets Euro III emission standards while also increasing propylene production), MIP-LTG (a catalytic cracking process), and MIP-DCR (Development and Industrial Application of MIP-DCR Process Technology, Gong Jianhong et al., Petroleum Refining and Chemicals, Vol. 44, No. 3, March 2013, pp. 9-14). At present, there are about 70 sets of MIP-CGP units in China, and in the future, several sets of FCC units will be converted into MIP units. When a new unit is started up, it is often impossible to use the catalytic cracking catalyst used when the unit is in normal operation, because its activity is too high, which easily causes huge fluctuations in operation and often fails to start up successfully. For this reason, the existing catalytic cracking units are usually started up with the balance agent used during normal production. However, there is often not enough balance agent when starting up with a balance agent, and the new unit does not have the balance agent produced by this unit available for use. The use of balance agents produced by other units does not match the unit well, resulting in a long start-up time. Therefore, the new unit needs a start-up catalyst with a high degree of matching of its physical and chemical properties to ensure stable and efficient start-up of the unit. In addition, during the daily operation of the unit, if the properties of the raw materials suddenly become heavier, resulting in catalyst poisoning, or if the unit has abnormal catalyst running, excellent start-up catalyst resources are required for rapid replacement or replenishment to ensure stable operation of the unit.

[0007] After research, the inventors of the present invention found that during the startup process of existing catalytic cracking units or catalytic cracking units, even if a catalytic cracking or catalytic cracking balance agent produced by a similar unit is used for startup, it still takes a long time to reach the designed operating conditions; and the replacement of fresh catalyst cannot be too fast, otherwise large fluctuations are likely to occur during the catalyst replacement process, and the stabilization time is long, often taking more than three months to achieve stability; however, surprisingly, when a composite startup catalyst with appropriately low cracking or cracking activity, a lower coke index, and a higher propylene index (or a higher gasoline index) is used, the replacement of the cracking or cracking catalyst designed for the catalytic cracking or catalytic cracking unit can be achieved efficiently and smoothly, achieving the reaction target of the designed catalyst.

[0008] Summary of the Invention

[0009] The first object of the present invention is to provide a composite start-up catalyst for use as a start-up catalyst in the start-up phase (including shutdown and maintenance start-up, and start-up of a new unit) of a catalytic cracking unit for heavy oil or high-density heavy oil, which can achieve efficient and stable start-up of a catalytic cracking unit of heavy oil or high-density heavy oil, such as an RTC unit.

[0010] A second object of the present invention is to provide a start-up catalyst for a catalytic cracking unit, particularly suitable for starting up a unit that produces both gasoline and propylene. This start-up catalyst is used during the start-up phase of a catalytic cracking unit that produces both propylene and gasoline, such as a MIP catalytic cracking unit (including shutdowns for maintenance, rapid replacement of equalizer after poisoning, or replenishment of catalyst due to abnormal agent loss in the unit), to achieve efficient and stable start-up of the unit.

[0011] The third object of the present invention is to provide a method for preparing the composite start-up catalyst.

[0012] A fourth object of the present invention is to provide a startup method for a catalytic cracking unit (such as an RTC process unit) for heavy oil or high-density heavy oil (such as intermediate-base heavy oil), wherein the method uses a catalytic cracking startup catalyst according to the present invention.

[0013] A fifth object of the present invention is to provide a method for starting up a catalytic cracking unit for producing more gasoline and propylene, wherein the method uses the catalytic cracking start-up catalyst according to the present invention.

[0014] In order to achieve the above-mentioned purpose, according to the first aspect of the present invention, there is provided a composite start-up catalyst, in particular a start-up catalyst for a catalytic cracking unit or a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises 15 to 95 weight % of component A catalyst, which is selected from a balance agent, and 5 to 85 weight % of component B catalyst, which is selected from one or more fresh catalysts, preferably a fresh catalytic cracking catalyst or catalytic cracking catalyst, and an optional component C catalyst; wherein the balance agent is preferably a catalytic cracking or catalytic cracking balance agent and / or a treated catalytic cracking or catalytic cracking balance agent, and the treatment may include demetallization treatment and / or particle size adjustment treatment, preferably, the cracking activity of the balance agent is 55 to 65; the component C catalyst contains 2 to 10 weight % of a modified metal oxide.

[0015] More particularly, the first aspect of the present invention relates to the following two types of composite start-up catalysts: a first type of composite start-up catalyst, which is a start-up catalyst for a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises 15 to 95 weight percent of a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, wherein the treatment may include demetallization treatment and / or particle size adjustment treatment, 5 to 85 weight percent of one or more fresh catalytic cracking catalysts, and an optional component C catalyst, wherein the optional component C catalyst contains 2 to 10 weight percent of a modified metal oxide, preferably, the modified metal is an alkaline earth metal; preferably, the cracking activity of the catalytic cracking balance agent is 55 to 65; and,

[0016] The second type of composite start-up catalyst is a start-up catalyst for a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst contains 15 to 95 weight percent of a catalytic cracking balancer and / or a treated catalytic cracking balancer, wherein the treatment may include demetallization treatment and / or particle size adjustment treatment, 5 to 85 weight percent of one or more fresh catalytic cracking catalysts, and an optional component C catalyst; wherein the optional component C catalyst contains 2 to 10 weight percent of a modified metal oxide, preferably, the modified metal is an alkaline earth metal; preferably, the cracking activity of the catalytic cracking balancer is 55 to 65.

[0017] The first series of composite start-up catalysts according to the first aspect are particularly used as start-up catalysts for catalytic cracking units, wherein, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises:

[0018] (1) 15 to 95 wt%, preferably 70 to 95 wt% of the catalyst of component A, and

[0019] (2) 5 to 85% by weight, preferably 5 to 30% by weight, of the component B catalyst,

[0020] Wherein, the catalyst of component A is a balance agent, preferably a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, and the treatment may include demetallization treatment and / or particle size adjustment treatment;

[0021] The component B catalyst is a fresh catalyst, and its active component includes a hollow multi-level pore ZSM-5 nanocrystalline material. The content of the hollow multi-level pore ZSM-5 nanocrystalline material is 5 to 15% by weight relative to the total weight of the component B catalyst, calculated on a dry basis.

[0022] The second series of composite start-up catalysts according to the first aspect are particularly used as start-up catalysts for catalytic cracking units, wherein the composite start-up catalysts comprise, based on the dry weight of the composite start-up catalysts,

[0023] (1) 20 to 90% by weight, preferably 75 to 85% by weight, of the catalyst of component A,

[0024] (2) 5 to 65% by weight, preferably 10 to 20% by weight, of the catalyst of component B,

[0025] (3) 5 to 15% by weight, preferably 5 to 10% by weight, of the catalyst of component C,

[0026] Wherein, the catalyst of component A is a balance agent, preferably a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, and the treatment may include demetallization treatment and / or particle size adjustment treatment;

[0027] The component B catalyst is selected from a fresh catalyst, and its active component is ZSM-5 molecular sieve. Preferably, on a dry basis, the content of the ZSM-5 molecular sieve is 5 to 15% by weight relative to the total weight of the component B catalyst;

[0028] The component C catalyst contains 2 to 10 weight percent of a modified metal oxide, wherein the modified metal is an alkaline earth metal.

[0029] The third series of composite start-up catalysts according to the first aspect, particularly for start-up catalysts of catalytic cracking units, is characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises:

[0030] (1) 15-95%, preferably 75-95%, of component A catalyst,

[0031] (2) 5 to 85%, preferably 5 to 25%, of component B catalyst,

[0032] Wherein, the component A catalyst is a balance agent, preferably a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, and the treatment may include demetallization treatment and / or particle size adjustment treatment;

[0033] The component B catalyst is selected from fresh catalysts, and its active component includes a modified small-grain Y-type molecular sieve material, and on a dry basis, the modified small-grain Y-type molecular sieve material content is 5-15% by weight of the component B catalyst. Preferably, the cracking activity of the component A catalyst is 55-65.

[0034] The fourth series of composite start-up catalysts according to the first aspect, particularly for start-up catalysts of catalytic cracking units, is characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises:

[0035] (1) 20-90%, preferably 75-90%, of component A catalyst,

[0036] (2) 5 to 65%, preferably 5 to 15%, of component B catalyst,

[0037] (3) 5 to 15%, preferably 5 to 10%, of component C catalyst,

[0038] Among them, the component A catalyst is a balance agent, preferably a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, the main active components of the component B catalyst include a modified small-grain Y-type molecular sieve and an optional ZSM-5 molecular sieve material, and the component C catalyst contains a carrier and a metal oxide, wherein the component C catalyst contains 2 to 10 weight percent of a modified metal oxide, preferably, the modified metal is an alkaline earth metal.

[0039] According to the second aspect of the present invention, the present invention provides a method for preparing the above-mentioned composite start-up catalyst, which comprises: preparing component B catalyst and optional component C catalyst, and physically mixing component A catalyst, component B catalyst and optional component C catalyst.

[0040] According to the third aspect of the present invention, the present invention also relates to the use of the composite start-up catalyst in the start-up of a newly built catalytic cracking unit or a catalytic cracking unit or a modified catalytic cracking unit or a catalytic cracking unit.

[0041] According to a fourth aspect of the present invention, the present invention also provides a method for starting up a catalytic cracking unit for heavy oil or high-density heavy oil, wherein during the start-up stage of the catalytic cracking unit, the heavy oil or high-density heavy oil is introduced into a catalytic cracking reactor and contacted with a fluidized catalytic cracking start-up catalyst according to the present invention to carry out a catalytic cracking reaction.

[0042] In the present invention, the heavy oil refers to a heavy oil having a density of 0.87 to 0.90 g / ml at 20°C. The high-density heavy oil (or heavier heavy oil) refers to a heavy oil having a density greater than 0.90 g / ml at 20°C, for example, a heavy oil having a density of 0.91 to 0.95 g / ml at 20°C. For example, the high-density heavy oil is an intermediate-base heavy oil, and the intermediate-base heavy oil is a heavy oil having a paraffin content of 15 to 25% by weight and a total cycloparaffin content of 25 to 35% by weight.

[0043] The method further includes: separating the oil and gas products after the cracking reaction from the catalyst, introducing the catalyst into a regenerator for regeneration after stripping, and then circulating it to a catalytic cracking reactor device for reaction, and introducing the oil and gas products into a subsequent oil and gas separation device for separation, wherein the catalyst is the composite start-up catalyst provided by the present invention.

[0044] According to the fifth aspect of the present invention, the present invention also provides a method for starting up a catalytic cracking unit for producing more gasoline and propylene, wherein during the startup stage of the catalytic cracking unit, raw oil is introduced into the catalytic cracking unit and contacted with the fluidized catalytic cracking start-up catalyst according to the present invention to carry out a catalytic cracking reaction.

[0045] The composite startup catalyst provided by the present invention is used during the startup phase of a catalytic cracking or catalytic cracking unit (including startup after a shutdown for maintenance or the start-up of a new unit), enabling efficient and stable startup of the unit. For example, using the startup catalyst can rapidly achieve expected values ​​for reaction indicators of the catalytic cracking or catalytic cracking unit, such as product distribution, significantly shortening the startup time.

[0046] The composite startup catalyst provided by the present invention exhibits appropriate catalytic cracking or catalytic cracking activity and a suitable distribution of catalytic cracking or catalytic cracking products. It simultaneously meets the fluidization performance requirements for particle size distribution, apparent bulk density, and abrasion resistance. It can be used as a startup catalyst for high-density heavy oil fluidized catalytic cracking units, enabling smooth and efficient startup of catalytic cracking or catalytic cracking units. For example, industrial applications have shown that using it to start up an RTC unit can significantly shorten the startup time, achieving the desired product distribution within a week.

[0047] The method for preparing the composite start-up catalyst provided by the present invention uses a catalytic cracking or catalytic cracking balance agent to compound with a specific fresh component B catalyst to obtain a composite start-up catalyst with the properties. Moreover, since it is prepared using the balance agent, the cost of the catalyst is low.

[0048] The method for preparing the composite start-up catalyst provided by the present invention utilizes a leveler and, by compounding with appropriate other catalyst components, can produce a catalyst with appropriate activity and product distribution. The composite start-up catalyst can have a high propylene factor and a low coke factor. Compared to using fresh catalyst, the use of a leveler can also reduce catalyst preparation costs.

[0049] The startup method of the catalytic cracking or catalytic cracking unit provided by the present invention can avoid the disadvantages of large conversion load, high coke yield and difficulty in stabilization caused by the high activity and high coke factor of the existing startup catalyst before adding the catalytic cracking catalyst or catalytic cracking catalyst used in normal production of the device by using the composite startup catalyst of the present invention. By combining lower activity with lower coke factor, during the startup process of the catalytic cracking or catalytic cracking unit, further combining with higher propylene factor or gasoline factor, the device can be quickly stabilized before adding the catalyst used in normal production; because the composite startup catalyst has better tolerance to fluctuations, after replacing a large amount of fresh catalyst, the device can achieve a new steady state faster at a higher replacement amount than the existing startup catalyst, thereby making the startup efficient and stable. The startup method provided by the present invention can greatly shorten the startup time, for example, quickly achieve the expected product distribution, and complete the startup within about a week.

[0050] In particular, the startup method for a high-density heavy oil catalytic cracking or catalytic cracking unit provided by the present invention can achieve efficient and stable startup of the unit, even completing startup and achieving stable operation within a week. For example, it can be used during the startup phase of an RTC process heavy oil catalytic cracking unit, such as a new heavy oil catalytic cracking unit or a heavy oil catalytic cracking unit after renovation or overhaul, to achieve efficient and stable startup of the unit.

[0051] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The following drawings are used to further illustrate the technical solutions of the present invention and constitute part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the drawings:

[0053] FIG1 shows a TEM image of a hollow multi-level porous ZSM-5 nanocrystalline material 1 according to the present invention;

[0054] FIG2 shows a SEM image of the modified small-grain Y-type molecular sieve material 1 according to the present invention. DETAILED DESCRIPTION

[0055] The following specific embodiments are used to describe the technical solution of the present invention in detail. It should be understood that the specific embodiments described in this specification are only used to illustrate the technical solution of the present invention and are not intended to limit the scope of the present invention.

[0056] Any specific numerical value disclosed in the present specification (including the endpoints of a numerical range) is not limited to the exact value of the numerical value, but should be understood to also include values ​​close to the exact value, such as all possible values ​​within ±5% of the exact value. Moreover, for a disclosed numerical range, the values ​​between the endpoints of the range, between the endpoints and the specific points in the range, and between the specific points can be arbitrarily combined to form one or more new numerical ranges, and these new numerical ranges should also be considered to be specifically disclosed herein.

[0057] Unless otherwise specified, the terms used in the specification of the present invention have the same meanings as commonly understood by those skilled in the art. If a term is defined herein and its definition is different from the commonly understood meaning in the art, the definition in this article shall prevail.

[0058] In the description of the present invention, except for the contents explicitly described, any matters or issues not mentioned are directly applicable to those known in the art without any changes. Moreover, any embodiment described herein can be freely combined with one or more other embodiments described herein, and the technical solutions or technical ideas formed thereby are considered part of the original disclosure or original description of the present invention, and should not be regarded as new content not disclosed or anticipated herein, unless a person skilled in the art considers that the combination is obviously unreasonable.

[0059] All patent and non-patent literature, including but not limited to textbooks and journal articles, mentioned in the specification of the present invention are incorporated herein by reference in their entirety.

[0060] In the present specification, the term "comprising" is synonymous with "including" and "containing" and is inclusive or open-ended, without excluding other unspecified elements. It should be understood that the term "comprising" includes the exclusive and closed term "consisting of." In the present specification, the term "support" and "substrate support" have the same meaning and are used equivalently in the present invention.

[0061] The measurement of the performance parameters disclosed in the description of the present invention, unless otherwise specified, is carried out by the most conventional methods in the art.

[0062] According to a first aspect of the present invention, the present invention provides a composite start-up catalyst, particularly a start-up catalyst for a catalytic cracking unit or a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises 15 to 95 weight percent of component A catalyst, which is selected from a balance agent, and 5 to 85 weight percent of component B catalyst, which is selected from one or more fresh catalysts, preferably a fresh catalytic cracking catalyst or catalytic cracking catalyst, and an optional component C catalyst; wherein the balance agent is preferably a catalytic cracking or catalytic cracking balance agent and / or a treated catalytic cracking or catalytic cracking balance agent, and the treatment may include demetallization treatment and / or particle size adjustment treatment, preferably, the cracking activity of the balance agent is 55 to 65; the component C catalyst contains 2 to 10 weight percent of a modified metal oxide.

[0063] The first series of composite start-up catalysts according to the first aspect are particularly used as start-up catalysts for catalytic cracking units, wherein, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises:

[0064] 15 to 95% by weight, preferably 70 to 95% by weight, of the catalyst of component A, and

[0065] 5 to 85% by weight, preferably 5 to 30% by weight, of the component B catalyst,

[0066] Wherein, the catalyst of component A is a balance agent, preferably a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, and the treatment may include demetallization treatment and / or particle size adjustment treatment;

[0067] The component B catalyst is selected from fresh catalysts, and its active component includes hollow multi-level pore ZSM-5 nanocrystalline material. The content of the hollow multi-level pore ZSM-5 nanocrystalline material is 5-15% by weight relative to the total weight of the component B catalyst on a dry basis.

[0068] The preparation method of the first series of composite start-up catalysts according to the first aspect is simple, and is obtained by physically blending the component A catalyst, the component B catalyst and optional other components uniformly.

[0069] According to one embodiment of the first series of composite start-up catalysts, the cracking activity of the component A catalyst is 55 to 65. The specific surface area of ​​the component A catalyst is ≥100m 2 / g, for example, 100 to 150 m 2The nickel content of the component A catalyst is ≤6000 μg / g, for example, 200-5800 μg / g, the vanadium content is ≤3000 μg / g, for example, 300-2800 μg / g, and the rare earth element content is ≤10000 μg / g, for example, 1000-9500 μg / g.

[0070] According to one embodiment of the first series of composite start-up catalysts of the first aspect above, in the composite start-up catalyst, the particle size distribution of the component A catalyst is as follows: the content of particles with a particle size of 0 to 20 μm (referring to a particle size greater than 0 and less than or equal to 20 microns) is ≤3.0% by volume, the content of particles with a particle size of 0 to 40 μm (referring to a particle size greater than 0 and less than or equal to 40 microns) is ≤18.0% by volume, the content of particles with a particle size of 0 to 149 μm (referring to the volume content of particles with a particle size greater than 0 and less than or equal to 149 microns) is ≥90.0% by volume, and the average particle size (or average particle size) calculated by volume is 60.0 to 80.0 μm. Wherein, the particle size distribution is measured by laser scattering method (NB / SH / T0951-2017, Determination of particle size distribution of catalytic cracking catalysts).

[0071] According to one embodiment of the first series of composite start-up catalysts of the first aspect, in the composite start-up catalyst, the cracking activity of the component A catalyst is 55 to 65, for example, 56, 58, 60, 62, or 64. The method for measuring the cracking activity is described in NB / SH / T0952-2017 (Determination of the Micro-Reaction Index of Catalytic Cracking Catalysts). The reaction temperature for measuring the cracking activity of the present invention is 520°C.

[0072] According to one embodiment of the first series of composite start-up catalysts of the first aspect, in the composite start-up catalyst, the component B catalyst has an apparent bulk density of 0.80 to 0.94 g / mL. The apparent bulk density is measured in accordance with NB / SH / T0954-2017 (Determination of Apparent Bulk Density of Catalytic Cracking Catalysts).

[0073] According to one embodiment of the first series of composite start-up catalysts of the first aspect above, the wear index of the composite start-up catalyst is ≤2.0, and the wear index is measured by the straight tube method according to standard NB / SH / T0964-2017 (Determination of wear index of catalytic cracking catalyst).

[0074] According to an embodiment of the first series of composite start-up catalysts of the first aspect above, in the composite start-up catalyst, the content of particles with a particle size of 0 to 20 μm of the component B catalyst is ≤2.0% by volume, the content of particles with a particle size of 0 to 40 μm is ≤18.0% by volume, the content of particles with a particle size of 0 to 149 μm is ≥90.0% by volume, and / or the average particle size of the component B catalyst is 60.0 to 85.0 μm.

[0075] According to one embodiment of the first series of composite start-up catalysts of the first aspect above, in the composite start-up catalyst, the active component of the component B catalyst is a hollow multi-level pore ZSM-5 nanocrystalline material, and the content of the hollow multi-level pore ZSM-5 nanocrystalline material is 5 to 15 weight % of the component B catalyst.

[0076] According to one embodiment of the first series of composite start-up catalysts of the first aspect, the hollow multi-level pore ZSM-5 nanocrystalline material has a hollow structure, an average grain size of 0.2-3.0 μm, a ratio of the bulk silicon-aluminum molar ratio to the surface silicon-aluminum molar ratio of 1.0-1.5, and a total specific surface area of ​​340-420 m 2 / g, mesopore specific surface area is 40-150m 2 / g, and / or, the N2 adsorption-desorption curves show an H4-type hysteresis loop.

[0077] According to an embodiment of the first series of composite start-up catalysts of the first aspect above, the relative crystallinity of the hollow multi-level pore ZSM-5 nanocrystalline material is 75-95%.

[0078] The hollow multi-level pore ZSM-5 nanocrystalline material can be purchased commercially or prepared according to existing methods. For example, the hollow multi-level pore ZSM-5 nanocrystalline material can be prepared according to the method disclosed in Chinese application CN116177561A, such as the method disclosed in claims 6 to 10 or Examples 1 to 4.

[0079] According to one embodiment of the first series of composite start-up catalysts of the first aspect above, the component B catalyst further includes a carrier (also called a matrix carrier), and the carrier is selected from natural clay, alumina carrier and silica carrier.

[0080] According to one embodiment of the first series of composite start-up catalysts of the first aspect above, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0081] According to one embodiment of the first series of composite start-up catalysts of the first aspect above, the component B catalyst contains, on a dry basis, 10 to 15 weight percent of active components, 70 to 80 weight percent of kaolin, 3 to 8 weight percent of pseudo-boehmite, 5 to 10 weight percent of aluminum sol and 0 to 5 weight percent of silica sol.

[0082] According to one embodiment of the first series of composite start-up catalysts of the first aspect, the composite start-up catalyst has an apparent bulk density of 0.90 to 0.94 g / mL and an abrasion index of ≤2.0.

[0083] According to an embodiment of the first series of composite start-up catalysts of the first aspect above, the composite start-up catalyst has a nickel content of ≤4000 μg / g, for example, 150-3800 μg / g, a vanadium content of ≤2500 μg / g, for example, 200-2300 μg / g, a content of particles with a particle size of 0-20 μm of ≤2.0% by volume, a content of particles with a particle size of 0-40 μm of ≤18.0% by volume, a content of particles with a particle size of 0-149 μm of ≥90.0% by volume, and an average particle size calculated by volume of 65.0-85.0 μm.

[0084] According to one embodiment of the first series of composite start-up catalysts of the first aspect, the cracking activity of the composite start-up catalyst is 58-62.

[0085] According to an embodiment of the first series of composite start-up catalysts of the first aspect, the coke factor of the composite start-up catalyst is ≤0.070, such as 0.40 to 0.50.

[0086] According to one embodiment of the first series of composite start-up catalysts of the first aspect, the propylene factor of the composite start-up catalyst is ≥0.44, such as 0.46-0.50.

[0087] The second series of composite start-up catalysts according to the first aspect are particularly used as start-up catalysts for catalytic cracking units, wherein the composite start-up catalysts comprise, based on the dry weight of the composite start-up catalysts,

[0088] (1) 20 to 90% by weight, preferably 75 to 85% by weight, of the catalyst of component A,

[0089] (2) 5 to 65% by weight, preferably 10 to 20% by weight, of the catalyst of component B,

[0090] (3) 5 to 15% by weight, preferably 5 to 10% by weight, of the catalyst of component C,

[0091] Among them, the component A catalyst is a balance agent, preferably a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, and the treatment may include demetallization treatment and / or particle size adjustment treatment. Preferably, the cracking activity of the component A catalyst is 55-65, preferably 57-64; the component B catalyst is selected from a fresh catalyst, and its active component includes ZSM-5 molecular sieve, and the content of the ZSM-5 molecular sieve is 5-15 weight% relative to the total weight of the component B catalyst on a dry basis; the component C catalyst contains 2-10 weight% of a modified metal oxide, and the modified metal is an alkaline earth metal.

[0092] The preparation method of the second series of composite start-up catalysts according to the first aspect is simple and can be obtained by physically blending the component A catalyst, the component B catalyst, the component C catalyst and any other optional components.

[0093] In the second series of composite start-up catalysts according to the first aspect above, the particle size distribution of the component A catalyst is as follows: the content of particles with a particle size (referring to diameter, or referred to as particle size) of 0 to 20 μm is ≤3.0% by volume, the content of particles with a particle size of 0 to 40 μm is ≤18.0% by volume, the content of particles with a particle size of 0 to 149 μm is ≥90.0% by volume, and the average particle size is 60.0 to 80.0 μm. Wherein, 0 to 20 μm means a particle size greater than 0 and not exceeding 20 microns, 0 to 40 μm means a particle size greater than 0 and not exceeding 40 microns, and 0 to 149 μm means a particle size greater than 0 and not exceeding 149 microns.

[0094] In the second series of composite start-up catalysts according to the first aspect, the cracking activity of the catalyst of component A is preferably 57 to 63, for example, 58, 60, or 62. The method for measuring the cracking activity is described in NB / SH / T 0952-2017 (Determination of the Micro-Reaction Index of Catalytic Cracking Catalysts or Catalytic Cracking Catalysts). The reaction temperature for measuring the cracking activity of the present invention is 520°C.

[0095] In the second series of composite start-up catalysts according to the first aspect above, the component A catalyst is a balance agent, which can be a catalytic cracking balance agent, or a treated catalytic cracking balance agent obtained by treatment, and the treatment can include demetallization treatment and / or particle size adjustment treatment. The demetallization treatment can adopt one or more of chemical demetallization and physical demetallization treatment methods. The chemical demetallization treatment is, for example, an ammonia method or an acid demetallization treatment, the acid method is, for example, demetallization treatment using a citric acid solution or a sulfuric acid solution, the physical demetallization treatment is, for example, magnetic separation, the particle size adjustment treatment is, for example, gas purging to purge out the fine powder therein, or sieving by screening. The balance agent is a balance agent produced by a catalytic cracking unit, for example, a balance agent produced by a DCC unit.

[0096] According to one embodiment of the second series of composite start-up catalysts of the first aspect, the specific surface area of ​​the component A catalyst is ≥100m 2 / g; nickel content ≤ 6000μg / g, vanadium content ≤ 3000μg / g, rare earth elements ≤ 10000μg / g. For example, the specific surface area of ​​the component A catalyst is 100-200m 2 / g or 100~150m 2 / g; the nickel content is 500-6000μg / g or 800-5800μg / g or 1000-3000μg / g, the vanadium content is 50-3000μg / g or 500-1000μg / g or 300-2800μg / g, and the rare earth element content is 500-10000μg / g or 1000-9500μg / g or 3000-6000μg / g.

[0097] According to one embodiment of the second series of composite start-up catalysts of the first aspect, the component B catalyst has an apparent bulk density of 0.80 to 0.94 g / mL, preferably 0.85 to 0.90 g / mL, and an abrasion index of ≤2.0.

[0098] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, the preparation method of the component B catalyst includes: slurrying a slurry of a matrix carrier, a ZSM-5 molecular sieve and optionally water, spray drying to obtain first catalyst particles, and optionally calcining.

[0099] According to an embodiment of the second series of composite start-up catalysts of the first aspect above, in the component B catalyst, the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume, and the average particle size is 60.0 to 85.0 μm.

[0100] According to an embodiment of the second series of composite start-up catalysts of the first aspect above, in the composite start-up catalyst, the active component of the component B catalyst is a ZSM-5 molecular sieve, and its content is 5 to 15% by weight of the component B catalyst on a dry basis. The ZSM-5 molecular sieve can be, for example, one or more of a hydrogen-type ZSM-5 molecular sieve and a transition metal-modified ZSM-5 molecular sieve, and the transition metal is, for example, one or more of rare earth, iron, cobalt, and nickel, and the ZSM-5 molecular sieve can further contain phosphorus. According to one embodiment, the ZSM-5 molecular sieve is a multi-level pore ZSM-5 molecular sieve, and the multi-level pore ZSM-5 molecular sieve is, for example, one or more of a hydrogen-type multi-level pore ZSM-5 molecular sieve, or a metal-modified multi-level pore ZSM-5 molecular sieve or a phosphorus-containing metal-modified multi-level pore ZSM-5 molecular sieve. Multi-level pore ZSM-5 molecular sieves can be purchased commercially or prepared according to existing methods. For example, the multi-level pore ZSM-5 molecular sieve can be a hollow multi-level pore ZSM-5 nanocrystalline material, which can be prepared according to the method disclosed in Chinese patent application CN116177561A, for example, according to the method disclosed in claims 6 to 10 or Examples 1 to 4 of the patent application. ZSM-5 molecular sieves that do not contain mesopores or have a mesopore volume of less than 0.02 ml / g are non-multi-level pore ZSM-5 molecular sieves or conventional ZSM-5 molecular sieves, while those with a mesopore volume greater than 0.2 ml / g are multi-level pore ZSM-5 molecular sieves. The ZSM-5 molecular sieve can be, for example, one or more of a ZRP molecular sieve (a non-multi-level porous phosphorus-containing ZSM-5 molecular sieve), a ZSP molecular sieve (a non-multi-level porous phosphorus- and transition metal-containing ZSM-5 molecular sieve), an MPZ molecular sieve (a mesoporous ZSM-5 molecular sieve), and an MPZ molecular sieve containing phosphorus and transition metals (called RMPZ, a mesoporous ZSM-5 molecular sieve).

[0101] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, the component B catalyst also includes a matrix carrier. On a dry basis, the content of the matrix carrier in the component B catalyst is 85 to 95% by weight of the component B catalyst, and the matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0102] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, the component B catalyst contains, on a dry basis, 8 to 15 weight percent of active components, 70 to 80 weight percent of kaolin, 3 to 8 weight percent of pseudo-boehmite, 3 to 10 weight percent of aluminum sol and 2 to 10 weight percent of silica sol.

[0103] According to one embodiment of the second series of composite start-up catalysts of the first aspect, the content of the oxide of the modifying metal in the component C catalyst is 2-10%, for example, 3-9%, such as 4%, 5%, 6%, 7%, or 8%; the content of the carrier is 90-98% by weight, and the metal oxide is an alkaline earth metal oxide. The carrier or matrix carrier is selected from one or more of natural clay, alumina carrier, and silica carrier; the alumina carrier is, for example, one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina, and activated alumina; the silica carrier is, for example, one or more of neutral silica sol, acidic silica sol, or alkaline silica sol.

[0104] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, the preparation method of the component C catalyst includes: mixing the matrix carrier with optional water for slurrying, spray drying to obtain second catalyst particles, modifying the modified metal by impregnation, drying, and calcining; or the preparation method of the component C catalyst includes: mixing the matrix carrier, modified metal salt solution and optional water for slurrying, spray drying to obtain third catalyst particles, and optionally calcining.

[0105] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, the component C catalyst contains, on a dry basis, 3 to 8 weight percent of modified metal oxide, 70 to 85 weight percent of kaolin, 3 to 8 weight percent of pseudo-boehmite, 3 to 8 weight percent of aluminum sol and 2 to 10 weight percent of silica sol.

[0106] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, the component C catalyst can be obtained by modifying inert particles with the modified metal element compound, or by adding the modified metal element compound to an inert particle precursor, slurrying, and then spray drying.

[0107] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, in the preparation method of the component C catalyst, the modified metal element compound is one or more of magnesium nitrate, barium nitrate, strontium nitrate or radium nitrate.

[0108] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, the composite start-up catalyst has an apparent bulk density of 0.90 to 0.94 g / mL.

[0109] According to an embodiment of the second series of composite start-up catalysts of the first aspect above, the wear index of the composite start-up catalyst is ≤2.0.

[0110] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, in the composite start-up catalyst: the nickel content is ≤4000 μg / g, and / or the vanadium content is ≤2500 μg / g, for example, the nickel content is 200-4000 μg / g, and / or the vanadium content is 300-2500 μg / g.

[0111] According to an embodiment of the second series of composite start-up catalysts of the first aspect above, in the composite start-up catalyst: the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume%, and / or the average particle size calculated by volume is 65.0 to 85.0 μm, preferably 70 to 80.0 μm.

[0112] According to one embodiment of the second series of composite start-up catalysts of the first aspect above, the cracking activity of the composite start-up catalyst is preferably 58-62.

[0113] According to an embodiment of the second series of composite start-up catalysts of the first aspect, the coke factor of the composite start-up catalyst is ≤0.070, for example, 0.040 to 0.065.

[0114] According to an embodiment of the second series of composite start-up catalysts of the first aspect above, the propylene factor of the composite start-up catalyst is ≥0.44, for example, 0.45 to 0.5.

[0115] The third series of composite start-up catalysts according to the first aspect, particularly for start-up catalysts of catalytic cracking units, is characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises:

[0116] (1) 15-95%, preferably 75-95%, of component A catalyst,

[0117] (2) 5 to 85%, preferably 5 to 25%, of component B catalyst,

[0118] Wherein, the component A catalyst is a balance agent, preferably a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, and the treatment may include demetallization treatment and / or particle size adjustment treatment;

[0119] The component B catalyst is selected from fresh catalysts, and its active component includes a modified small-grain Y-type molecular sieve material, and on a dry basis, the modified small-grain Y-type molecular sieve material content is 5-15% by weight of the component B catalyst. Preferably, the cracking activity of the component A catalyst is 55-65.

[0120] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, the start-up catalyst can be obtained by physically mixing the component A catalyst and the component B catalyst evenly.

[0121] According to one embodiment of the third series of composite start-up catalysts of the first aspect, the specific surface area of ​​the component A catalyst is ≥100m 2 / g, for example, 100 to 150 m 2 / g; nickel content ≤6000μg / g, for example, 200-5800μg / g, vanadium content ≤4000μg / g, for example, 500-3500μg / g, iron content ≤5000μg / g, for example, 500-4500μg / g, rare earth elements ≥10000μg / g, for example, 10000-50000μg / g.

[0122] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, the particle size distribution of the component A catalyst is: the content of particles with a particle size of 0 to 20 μm (referring to a particle size greater than 0 and less than or equal to 20 microns) is ≤3.0% by volume, the content of particles with a particle size of 0 to 40 μm (referring to a particle size greater than 0 and less than or equal to 40 microns) is ≤18.0% by volume, the content of particles with a particle size of 0 to 149 μm (referring to the volume content of particles with a particle size greater than 0 and less than or equal to 149 microns) is ≥90.0% by volume, and the average particle size (or average particle size) is 60.0 to 80.0 μm. The particle size distribution is measured by laser scattering (NB / SH / T0951-2017, Determination of Particle Size Distribution of Catalytic Cracking Catalysts).

[0123] According to an embodiment of the third series of composite start-up catalysts of the first aspect, in the start-up catalyst, the cracking activity of the component A catalyst is 55-65.

[0124] According to an embodiment of the third series of composite start-up catalysts of the first aspect, the coke factor of the start-up catalyst is ≤0.140; and / or the gasoline factor of the start-up catalyst is ≥0.420.

[0125] The cracking activity measurement method is described in NB / SH / T0952-2017, Determination of the Micro-reaction Activity Index of Catalytic Cracking Catalysts. The reaction temperature for the cracking activity of the present invention is 460°C.

[0126] The coke factor and gasoline factor can be obtained by mixing heavy oil with the cracking catalyst at a temperature of 520°C, a catalyst-oil ratio of 10 weight ratio, and a weight hourly space velocity of 10h -1The reaction is carried out in an FFB fixed fluidized bed reactor and calculated, wherein the coke factor = coke yield / conversion rate, and the gasoline factor = gasoline yield / conversion rate. The heavy oil preferably has a density of 0.8730 to 0.9299 g / cc at 20°C.

[0127] According to one embodiment of the third series of composite start-up catalysts of the first aspect, the catalyst component B has an apparent bulk density of 0.80 to 0.94 g / mL. The apparent bulk density is measured according to NB / SH / T0954-2017, Determination of Apparent Bulk Density of Catalytic Cracking Catalysts.

[0128] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, the wear index of the start-up catalyst is ≤2.0, and the wear index is determined according to the standard NB / SH / T0964-2017, Determination of Wear Index of Catalytic Cracking Catalysts, straight tube method.

[0129] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, the content of particles with a particle size of 0 to 20 μm of the component B catalyst is ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume%, and the average particle size is 60.0 to 85.0 μm.

[0130] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, the active component of the component B catalyst is a modified small-grain Y-type molecular sieve material, and the content of the modified small-grain Y-type molecular sieve material is 5-15% by weight of the component B catalyst.

[0131] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, in the modified small-grain Y-type molecular sieve material: the RE2O3 content is 0-18% by weight, and the Na2O content does not exceed 1% by weight. Preferably, the average grain size of the modified small-grain Y-type molecular sieve material is 0.5-1.0 μm, for example, 0.5-0.9 μm or 0.5-0.8 μm. Preferably, the unit cell constant of the modified small-grain Y-type molecular sieve material is preferably 2.430-2.470 nm. The proportion of non-framework aluminum content in the modified small-grain Y-type molecular sieve material to the total aluminum content is preferably not higher than 30%. Preferably, the ratio of the B acid content to the L acid content of the modified small-grain Y-type molecular sieve material is preferably not less than 2.5. Preferably, the external surface acid content of the modified small-grain Y-type molecular sieve material is preferably 150-300 μmol / g. Preferably, the total specific surface area of ​​the modified small-grain Y-type molecular sieve material is 580-650 m 2 ˙g -1 .

[0132] According to an embodiment of the third series of composite start-up catalysts of the first aspect above, the relative crystallinity of the modified small-grain Y-type molecular sieve material is 45-65%.

[0133] Preferably, the lattice collapse temperature of the modified small-grain Y-type molecular sieve material is not lower than 1030°C.

[0134] The modified small-grain Y-type molecular sieve material can be purchased commercially or prepared according to existing methods. For example, the modified small-grain Y-type molecular sieve material can be prepared according to the small-grain preparation method disclosed in Chinese application 202011180404.5 (CN114433215B), such as any one of claims 2 to 17 of the application or Examples 1 to 3.

[0135] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, the component B catalyst further includes a carrier (also called a matrix carrier), and the carrier is selected from natural clay, alumina carrier and silica carrier.

[0136] Preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0137] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, the component B catalyst contains, on a dry basis, 10 to 15 weight percent of active components, 70 to 80 weight percent of kaolin, 3 to 8 weight percent of pseudo-boehmite, 5 to 10 weight percent of aluminum sol and 0 to 5 weight percent of silica sol.

[0138] According to an embodiment of the third series of composite start-up catalysts of the first aspect, the start-up catalyst has an apparent bulk density of 0.90 to 0.94 g / mL and an abrasion index of ≤2.0.

[0139] According to an embodiment of the third series of composite start-up catalysts of the first aspect above, the nickel content of the start-up catalyst is ≤5000μg / g, the vanadium content is ≤3500μg / g, the iron content is ≤4500μg / g, and / or the content of particles with a particle size of 0-20μm is ≤2.0% by volume, the content of particles with a particle size of 0-40μm is ≤18.0% by volume, the content of particles with a particle size of 0-149μm is ≥90.0% by volume, and the average particle size is 65.0-85.0μm.

[0140] According to one embodiment of the third series of composite start-up catalysts of the first aspect above, the cracking activity of the start-up catalyst is 55-65, for example, 60-65 or 62-65, and / or the coke factor is ≤0.140, for example, 0.1-0.14, and the gasoline factor is ≥0.420, for example, 0.42-0.47 or 0.44-0.46.

[0141] The fourth series of composite start-up catalysts according to the first aspect, particularly for start-up catalysts of catalytic cracking units, is characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises:

[0142] (1) 20-90%, preferably 75-90%, of component A catalyst,

[0143] (2) 5 to 65%, preferably 5 to 15%, of component B catalyst,

[0144] (3) 5 to 15%, preferably 5 to 10%, of component C catalyst,

[0145] Among them, the component A catalyst is a balance agent, preferably a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, the main active components of the component B catalyst include a modified small-grain Y-type molecular sieve and an optional ZSM-5 molecular sieve material, and the component C catalyst contains a carrier and a metal oxide, wherein the component C catalyst contains 2 to 10 weight percent of a modified metal oxide, preferably, the modified metal is an alkaline earth metal.

[0146] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect above, the catalyst is prepared by physically blending the component A catalyst, the component B catalyst and the component C catalyst in a certain proportion.

[0147] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect, in the catalyst, the component A catalyst has a specific surface area of ​​≥100m 2 / g, for example, 100-150m 2 / g; nickel content ≤6000μg / g, for example, 200-5500μg / g, vanadium content ≤5000μg / g, for example, 500-3500μg / g, iron content ≤5000μg / g, for example, 500-4700μg / g, sodium content ≤3000μg / g, for example, 200-2000μg / g, calcium content ≤3000μg / g, for example, 200-2000μg / g, Y-type molecular sieve crystallinity ≥20.0%, for example, 20-30%, ZSM-5 molecular sieve crystallinity ≥2.0%, for example, 2-10%. The crystallinity measurement method adopts NB / SH / T6024-2021 method for measurement.

[0148] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect, in the start-up catalyst, the content of particles with a particle size of 0 to 20 μm in the component A catalyst is ≤3.0% by volume, the content of particles with a particle size of 0 to 40 μm is ≤18.0% by volume, the content of particles with a particle size of 0 to 149 μm is ≥90.0% by volume, and the average particle size is 60.0 to 80.0 μm. The particle size refers to the particle diameter of the particles.

[0149] For the catalyst of the present invention, the particle size distribution is as described in NB / SH / T0951-2017, Determination of Particle Size Distribution of Catalytic Cracking Catalysts (Laser Scattering Method). The content of particles with a particle size of 0-20 μm refers to the cumulative volume fraction of particles with a particle size of 0-20 μm, and the content of particles with a particle size of 0-40 μm and 0-149 μm is similar.

[0150] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect, in the start-up catalyst, the cracking activity of the catalyst component A is 55 to 65. In the present invention, the cracking activity is measured in accordance with NB / SH / T0952-2017, "Micro-reaction Activity of Catalytic Cracking Catalysts." The catalyst component A may be a catalytic cracking balancer.

[0151] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect, in the catalyst, the component B catalyst has an apparent bulk density of 0.80 to 0.94 g / mL and an abrasion index of ≤2.0. For apparent bulk density measurement, refer to the standard: NB / SH / T0954-2017 Method for Determination of Apparent Bulk Density of Catalytic Cracking Catalysts; for abrasion index measurement, refer to the standard: NB / SH / T0964-2017 Determination of Abrasion Index of Catalytic Cracking Catalysts (Straight Tube Method)

[0152] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect above, in the catalyst, the content of particles with a particle size of 0 to 20 μm of the component B catalyst is ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume%, and / or the average particle size is 60.0 to 85.0 μm.

[0153] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect above, in the catalyst, the active component of the component B catalyst is a modified small-grain Y-type molecular sieve and an optional ZSM-5 molecular sieve, and the content of the active component on a dry basis is 5 to 15% by weight of the component B catalyst based on the dry basis weight of the component B catalyst; the ZSM-5 molecular sieve is an existing ZSM-5 molecular sieve, for example, the ZSM-5 molecular sieve can be a conventional ZSM-5 molecular sieve or a multi-level pore ZSM-5 molecular sieve or a metal-modified multi-level pore ZSM-5 molecular sieve or a hollow mesoporous ZSM-5 molecular sieve. The conventional ZSM-5 molecular sieve refers to a conventionally produced ZSM-5 molecular sieve without mesopores, which can be a hydrogen-type ZSM-5 molecular sieve or a ZSM-5 molecular sieve modified by phosphorus and / or modified metals.

[0154] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect above, the weight ratio of the modified small-grain Y-type molecular sieve to the ZSM-5 molecular sieve is greater than 2, for example, 2-100:1 or 2-10:1, calculated on a dry basis.

[0155] The modified small-grain Y-type molecular sieve can be purchased commercially or prepared according to existing methods, for example, according to the method disclosed in Chinese patent application 202011180404.5 (CN114433215B), for example, according to the method disclosed in any one of claims 2-17 of the application or any one of the methods disclosed in Examples 1-3. The average grain size of the modified small-grain Y-type molecular sieve is preferably 300-700nm, for example, 400nm, 500nm and 600nm. It is calculated using the Scherrer formula by the XRD method. The modification refers to: rare earth modification and gas phase ultra-stable and / or hydrothermal ultra-stable modification.

[0156] The modified small-grain Y-type molecular sieve may have a rare earth element content calculated as RE2O3 of no more than 20% by weight, for example, 1 to 20% by weight or 2 to 18% by weight.

[0157] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect above, the modified small-grain Y-type molecular sieve has a silicon-to-aluminum ratio (SiO2 / Al2O3 molar ratio) of, for example, 5.1 to 10.

[0158] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect above, in the start-up catalyst, the component B catalyst also includes a matrix carrier, whose content is 85 to 95% by weight of the component B catalyst, and the matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0159] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect above, the component B catalyst includes 2-10 weight% of modified small-grain Y-type molecular sieve, 1-5 weight% of ZSM-5 molecular sieve, 65-85 weight% of clay such as kaolin, 3-10 weight% of pseudo-boehmite, 3-10 weight% of aluminum sol and 3-10 weight% of silica sol.

[0160] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect, in the catalyst, the metal oxide content (referred to as modified metal oxide) of the catalyst component C, or the loading amount thereof, is 2 to 10% by weight relative to the weight of the catalyst component C. The metal oxide may be one or more of magnesium oxide, barium oxide, strontium oxide, and radium oxide.

[0161] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect, in the catalyst, the component C catalyst can be an inert microsphere modified with a modified metal element, i.e., loaded with the metal element, such as obtained by impregnation with a metal salt solution, or can be obtained by adding a metal element, such as a metal salt, to a catalyst precursor and then spray-drying. The modified metal element in the component C catalyst is one or more of Mg, Ba, Sr, and Ra, preferably Mg and / or Ba.

[0162] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect, the component C catalyst comprises: 3-10 wt% pseudo-boehmite, 3-10 wt% alumina sol, 3-10 wt% silica sol, 2-10 wt% alkaline earth metal oxide, and 70-89 wt% clay, such as kaolin. The alkaline earth metal is one or more of Mg, Ba, Sr, and Ra, preferably Mg and / or Ba.

[0163] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect above, in the start-up catalyst according to the present invention, the metal salt used to prepare the component C catalyst can be one or more of magnesium nitrate, barium nitrate, strontium nitrate or radium nitrate.

[0164] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect, the apparent bulk density of the start-up catalyst is 0.90 to 0.94 g / mL.

[0165] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect, the wear index of the start-up catalyst is ≤2.0; the unit of the wear index is %h -1 .

[0166] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect above, the specific surface area of ​​the start-up catalyst is ≥110m 2 / g, for example, 110-200m 2 / g.

[0167] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect above, the nickel content of the start-up catalyst is ≤5000 μg / g, for example, 500-4500 μg / g, the vanadium content is ≤4000 μg / g, for example, 200-3500 μg / g, the iron content is ≤4000 μg / g, for example, 500-4000 μg / g, the sodium content is ≤2000 μg / g, for example, 100-1500 μg / g, the calcium content is ≤2000 μg / g, for example, 50-1800 μg / g, the content of particles with a particle size of 0-20 μm is ≤2.0% by volume, the content of particles with a particle size of 0-40 μm is ≤18.0% by volume, the content of particles with a particle size of 0-149 μm is ≥90.0% by volume, and / or its average particle size is 65.0-85.0 μm.

[0168] According to one embodiment of the fourth series of composite start-up catalysts of the first aspect, the start-up catalyst has a cracking activity of 55 to 65, a coke factor ≤ 0.125, e.g., 0.05 to 0.12, a gasoline factor ≥ 0.430, e.g., 0.43 to 0.48, and a propylene factor ≥ 0.420, e.g., 0.42 to 0.47. The cracking activity of the start-up catalyst is determined using the NB / SH / T0952-2017 method.

[0169] In the present invention, the coke factor, gasoline factor and propylene factor are measured as follows: the reaction temperature is 520 ° C, the catalyst-oil ratio is 10:1 by weight, and the weight hourly space velocity is 10h -1 Hydrogenated heavy oil feedstock is evaluated on a fixed fluidized bed apparatus. Conversion = dry gas yield + liquefied gas yield + gasoline yield + coke yield. Coke factor = coke yield / conversion, gasoline factor = gasoline yield / conversion, and propylene factor = propylene yield / liquefied gas yield, where yields are weight yields.

[0170] According to an embodiment of the fourth series of composite start-up catalysts of the first aspect above, the start-up catalyst is obtained by physically mixing component A catalyst, component B catalyst and component C catalyst in a certain proportion.

[0171] According to the second aspect of the present invention, the present invention provides a preparation method for preparing a composite start-up catalyst according to the above-mentioned first aspect, comprising: preparing a component B catalyst and an optional component C catalyst, and physically mixing the component A catalyst, the component B catalyst and the optional component C catalyst.

[0172] According to the first series of the second aspect, the method for preparing the first series of composite start-up catalysts according to the first aspect comprises: preparing a component B catalyst, and physically mixing the component A catalyst and the component B catalyst in a certain proportion, wherein the dry weight ratio of the component A catalyst: the component B catalyst is (15-95): (5-85), for example, 80-95:5-20.

[0173] According to one embodiment of the first series of preparation methods of the second aspect above, the cracking activity of the component A catalyst is 55 to 65. The component A catalyst can be a catalytic cracking balance agent, or a treated catalytic cracking balance agent obtained by treating the balance agent; the treatment can include demetallization treatment and / or particle size adjustment treatment. The demetallization treatment can adopt one or more of chemical demetallization and physical demetallization treatment methods. The chemical demetallization treatment is, for example, an ammonia method, an acid demetallization treatment, such as demetallization treatment with sulfuric acid solution or citric acid solution; the physical demetallization treatment is, for example, magnetic separation; the particle size adjustment treatment is, for example, gas purging to purge out the fine powder therein, or sieving through a sieve. The catalytic cracking balance agent is a balance agent produced by a catalytic cracking unit, such as a DCC unit balance agent; the catalytic cracking balance agent is a balance agent produced by a catalytic cracking unit.

[0174] According to one embodiment of the first series of preparation methods of the second aspect, the preparation method of the Component B catalyst comprises: forming a slurry with a matrix support, a hollow multi-level porous ZSM-5 nanocrystalline material, and water, spray drying, and optionally calcining. Alternatively, the preparation method of the Component B catalyst comprises: mixing the hollow multi-level porous ZSM-5 nanocrystalline material, the support, and water, and slurrying, wherein the support is, for example, one or more of aluminum sol, silica sol, acidified pseudo-boehmite, hydrated alumina, and activated alumina.

[0175] According to one embodiment of the first series of preparation methods of the second aspect above, the preparation method of the component B catalyst comprises:

[0176] (1) Pseudoboehmite and water are uniformly mixed, hydrochloric acid is added, wherein the acid-aluminum ratio is 0.15-0.25 (the weight ratio of HCl to pseudoboehmite calculated as Al2O3), and then aged at 60-75°C for 1-2 hours to form a first slurry, wherein the alumina content of the first slurry is preferably 8-15% by weight;

[0177] (2) forming a second slurry by combining the first slurry, the active component, aluminum sol, kaolin, optionally silica sol, and water; the second slurry preferably has a solid content of 20 to 40% by weight;

[0178] (3) spray drying;

[0179] (4) calcination, wherein the calcination temperature is 400° C. or higher, for example, 500-600° C., and the calcination time is 1 hour or higher, for example, 2-5 hours;

[0180] (5) Exchange with ammonium salt.

[0181] According to one embodiment of the preparation method of the above-mentioned component B catalyst, the step (5) is carried out as follows: the catalyst particles obtained by the spray drying, the ammonium salt and water are mixed in a weight ratio of 1: (0.1-1): (5-15) to perform ammonium exchange, and optionally wash, so that the Na2O content in the catalyst particles is less than 0.15 weight%; preferably, the conditions of the ammonium exchange include: a temperature of 40°C or above, for example, 50-100°C, and a time of 0.5 hour or above, for example, 0.5-2 hours; the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate.

[0182] According to one embodiment of the first series of preparation methods of the second aspect above, in the preparation method of the component B catalyst, the matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0183] The second series of methods according to the second aspect above for preparing the second series of composite start-up catalysts according to the first aspect above include: preparing a component B catalyst and an optional component C catalyst, and physically blending the component A catalyst, the component B catalyst and the component C catalyst in a certain proportion, wherein the dry basis weight ratio of the component A catalyst: the component B catalyst: the component C catalyst is (20-90): (5-65): (5-15), for example, (60-90): (5-30): (5-10).

[0184] According to one embodiment of the second series of preparation methods of the second aspect above, the cracking activity of the component A catalyst is 55 to 65. The component A catalyst is a balance agent, and the balance agent can be a catalytic cracking balance agent, or obtained by treating the balance agent; the treatment can include demetallization treatment and / or particle size adjustment treatment. The demetallization treatment can adopt one or more of chemical demetallization and physical demetallization treatment methods. The chemical demetallization treatment is, for example, an ammonia method, an acid demetallization treatment, such as demetallization treatment with sulfuric acid solution or citric acid solution; the physical demetallization treatment is, for example, magnetic separation; the particle size adjustment treatment is, for example, gas purging to purge out the fine powder therein, or sieving through a sieve. The catalytic cracking balance agent is a balance agent produced by a catalytic cracking unit, such as a DCC unit balance agent; the catalytic cracking balance agent is a balance agent produced by a catalytic cracking unit.

[0185] According to one embodiment of the second series of preparation methods of the second aspect, the method for preparing the component B catalyst comprises: forming a slurry with a matrix carrier, a ZSM-5 molecular sieve and water, spray drying, and optionally calcining.

[0186] According to one embodiment of the second series of preparation methods of the second aspect above, the method for preparing the component B catalyst includes: mixing and slurrying the ZSM-5 molecular sieve, the carrier and water, wherein the carrier is, for example, one or more of aluminum sol, silica sol, acidified pseudo-boehmite, hydrated alumina, and activated alumina.

[0187] According to one embodiment of the second series of preparation methods of the second aspect above, the method for preparing the component B catalyst comprises:

[0188] (1) Pseudoboehmite and water are uniformly mixed, hydrochloric acid is added, and the acid-aluminum ratio is 0.15-0.25 (the weight ratio of HCl to pseudoboehmite calculated as Al2O3), and the mixture is aged at 60-75°C for 1-2 hours to form a first slurry. The alumina content of the first slurry is preferably 8-15% by weight;

[0189] (2) forming a second slurry by combining the first slurry, the active component, aluminum sol, kaolin, optionally silica sol, and water; the second slurry preferably has a solid content of 20 to 40% by weight;

[0190] (3) spray drying;

[0191] (4) calcination, wherein the calcination temperature is 400° C. or higher, for example, 500-600° C., and the calcination time is 1 hour or higher, for example, 2-5 hours;

[0192] (5) Exchange with ammonium salt.

[0193] According to one embodiment of the method for preparing the above-mentioned component B catalyst, the step (5) is carried out as follows: the catalyst particles obtained by the spray drying, the ammonium salt and water are mixed in a weight ratio of 1: (0.1-1): (5-15) to perform ammonium exchange, and optionally wash, so that the Na2O content in the catalyst particles is less than 0.15 weight%; the conditions of the ammonium exchange include: a temperature of 40°C or above, for example, 50-100°C, and a time of 0.5 hours or above, for example, 0.5-2 hours; the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate.

[0194] According to one embodiment of the second series of preparation methods of the second aspect above, in the preparation method of the component B catalyst, the matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0195] According to one embodiment of the second series of preparation methods of the second aspect above, in the method for preparing the component C catalyst, the matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0196] According to one embodiment of the second series of preparation methods of the second aspect above, in the method for preparing the component C catalyst, the modified metal modification is carried out by impregnation, and the particles obtained by spray drying can be mixed with a solution containing a modified metal compound for impregnation, and then dried and calcined. The impregnation can be, for example, equal volume impregnation or excess impregnation.

[0197] According to one embodiment of the second series of preparation methods of the second aspect above, the method for preparing the component C catalyst comprises:

[0198] A. Pseudoboehmite and water are uniformly mixed, hydrochloric acid is added, and the acid-aluminum ratio is 0.15-0.25 (weight ratio of HCl to pseudoboehmite calculated as Al2O3). The mixture is aged at 60-75°C for 1-2 hours to form a third slurry. The alumina content of the third slurry is preferably 8-15% by weight.

[0199] B. forming a fourth slurry from the third slurry, alumina sol, kaolin, optional silica sol and water; the solid content of the fourth slurry is preferably 20 to 40 wt %;

[0200] C. spray drying;

[0201] D. calcination, the calcination temperature is, for example, 500 to 600° C., and the calcination time is, for example, 1 to 5 hours;

[0202] E. Impregnating the product of step D with an aqueous solution of an alkaline earth metal salt at a temperature of, for example, 40-60° C. for a time of, for example, 0.5-2.5 hours, followed by drying and calcining at a temperature of, for example, 500-600° C. for a time of, for example, 1-5 hours. The impregnation may be equal volume impregnation or excess impregnation.

[0203] According to one embodiment of the second series of preparation methods of the second aspect above, the method for preparing the component C catalyst comprises:

[0204] S1. The pseudo-boehmite and water are mixed uniformly, hydrochloric acid is added, the acid-aluminum ratio is 0.15 to 0.25 (the weight ratio of HCl to the pseudo-boehmite in terms of Al2O3), aged at 60 to 75 ° C for 1 to 2 hours to form a fifth slurry, the alumina content of the fifth slurry is preferably 8 to 15% by weight;

[0205] S2. The fifth slurry, an alkaline earth metal salt, aluminum sol, kaolin, optionally silica sol and water form a sixth slurry; the solid content of the sixth slurry is preferably 20 to 40% by weight;

[0206] S3. Spray drying;

[0207] S4. Calcination, the calcination temperature is, for example, 500 to 600° C., and the calcination time is, for example, 1 to 5 hours.

[0208] Preferably, in the preparation methods of the component B catalyst and the component C catalyst, the calcination temperature can be 400 to 600° C., and the calcination time can be, for example, 1 to 6 hours.

[0209] According to one embodiment of the second series of preparation methods of the second aspect, the methods for preparing the component B catalyst or the component C catalyst may further include: mixing the spray-dried catalyst particles, an ammonium salt, and water in a weight ratio of 1:(0.1-1):(5-15) to perform ammonium exchange, and optionally washing, to reduce the Na2O content in the catalyst particles to less than 0.15% by weight. Preferably, the ammonium exchange is performed at a temperature of 50-100°C for a time of 0.5-2 hours. The ammonium salt may be selected from one or more of ammonium chloride, ammonium sulfate, and ammonium nitrate.

[0210] The third series of methods according to the second aspect are used to prepare the third series of composite start-up catalysts according to the first aspect, comprising physically mixing the component A catalyst and the component B catalyst uniformly.

[0211] According to one embodiment of the third series of preparation methods of the second aspect above, the method further includes preparing the component B catalyst and an optional component C catalyst, wherein the preparation method of the component B catalyst includes: mixing a carrier and / or a carrier precursor, a modified small-grain Y-type molecular sieve material and water, beating the mixture to form a slurry, spray drying, and optionally calcining to obtain catalyst microspheres; ammonium exchange is performed on the obtained catalyst microspheres, and the ammonium exchange makes the Na2O content in the obtained component B catalyst less than 0.15 weight%; preferably, the catalyst microspheres, ammonium salt and water are mixed in a weight ratio of 1: (0.1~1): (5~15) for ammonium exchange; and the conditions of the ammonium exchange include: a temperature of 50~100°C and a time of 0.5~2 hours, and the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate; and / or, the preparation method of the component C catalyst includes: modifying the inert microspheres with metal elements, or adding metal elements to the catalyst precursor, and then spray drying.

[0212] According to one embodiment of the third series of preparation methods of the second aspect above, the preparation method of the component B catalyst includes mixing and slurrying a modified small-grain Y-type molecular sieve material, a carrier and water, wherein the carrier is, for example, one or more of aluminum sol, silica sol, acidified pseudo-boehmite, hydrated alumina, and activated alumina.

[0213] According to a preferred embodiment, the preparation method of the component B catalyst comprises:

[0214] (1) Pseudoboehmite and water are uniformly mixed, hydrochloric acid is added, and the acid-aluminum ratio is 0.15-0.25:1 (weight ratio of HCl to pseudoboehmite calculated as Al2O3), and the mixture is aged at 60-75°C for 1-2 hours to form a first slurry. The alumina content of the first slurry is preferably 8-15% by weight;

[0215] (2) forming a second slurry by combining the first slurry, the active component, aluminum sol, kaolin, optionally silica sol, and water; the solid content of the second slurry is preferably 20 to 40% by weight;

[0216] (3) spray drying;

[0217] (4) calcination, the calcination temperature is, for example, 500 to 600° C., and the calcination time is, for example, 2 to 5 hours;

[0218] (5) Exchange with ammonium salt.

[0219] According to a more preferred embodiment, the preparation method of the component B catalyst further includes ammonium exchange: the catalyst particles obtained by the spray drying, ammonium salt and water are mixed in a weight ratio of 1: (0.1 to 1): (5 to 15) for ammonium exchange, and optional washing, so that the Na2O content in the catalyst microspheres is less than 0.15 weight%; the conditions of the ammonium exchange include: a temperature of 50 to 100°C and a time of 0.5 to 2 hours; the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate.

[0220] The fourth series of methods according to the second aspect are used to prepare the fourth series of composite start-up catalysts according to the first aspect, comprising physically mixing the component A catalyst, the component B catalyst and the component C catalyst.

[0221] According to one embodiment of the fourth series of preparation methods of the second aspect above, the preparation method of the component B catalyst in the start-up catalyst includes: slurrying, spray drying, and optionally calcining a slurry of the matrix carrier and modified small-grain Y-type molecular sieve, ZSM-5 molecular sieve, and water.

[0222] According to one embodiment of the fourth series of preparation methods of the second aspect above, the preparation method of the component C catalyst in the start-up catalyst is selected from the following methods: Method 1, which includes: slurrying and spray drying the matrix carrier, metal modification by impregnation, drying, and roasting; or, Method 2, which includes: uniformly mixing the matrix carrier and the metal salt solution, slurrying, spray drying, and optionally roasting.

[0223] According to one embodiment of the fourth series of preparation methods of the second aspect above, the component C catalyst in the start-up catalyst is a mixture of the compositions obtained by the above methods 1 and 2.

[0224] According to one embodiment of the fourth series of preparation methods of the second aspect above, the preparation method of the component B and / or component C catalyst in the start-up catalyst further includes: mixing the catalyst particles obtained by the spray drying, an ammonium salt and water in a weight ratio of 1: (0.1-1): (5-15) to perform ammonium exchange, and optionally washing, so that the Na2O content in the component B catalyst and the component C catalyst is each less than 0.15 weight%; wherein the conditions for the ammonium exchange include: a temperature of 50-100°C and a time of 0.5-2 hours; and the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate.

[0225] According to a third aspect of the present invention, a composite start-up catalyst according to the present invention is provided for use in the start-up of a newly constructed catalytic cracking or catalytic cracking unit or a modified catalytic cracking or catalytic cracking unit. Such applications include: new start-up of a modified unit, rapid replacement of a balancer after poisoning, or replenishment of catalyst when the unit experiences abnormal catalyst loss, thereby enabling efficient and stable start-up, rapid replacement of a balancer, and rapid replenishment of catalyst.

[0226] According to one embodiment of the first series of uses of the third aspect of the present invention, the first series of composite start-up catalysts according to the above-mentioned first aspect are used in a start-up method of a newly built catalytic cracking unit or a modified catalytic cracking unit; preferably, the catalytic cracking unit is a catalytic cracking unit for heavy oil.

[0227] According to one embodiment of the second series of uses of the third aspect of the present invention, the second series of composite start-up catalysts according to the above-mentioned first aspect are used in a start-up method of a newly built catalytic cracking unit or a modified catalytic cracking unit; preferably, the catalytic cracking unit is a catalytic cracking unit for high-density heavy oil.

[0228] According to one embodiment of the first and second series of uses of the third aspect of the present invention, the catalytic cracking unit adopts the RTC process.

[0229] According to one embodiment of the third series of uses of the third aspect of the present invention, the third series of composite start-up catalysts according to the first aspect are used in a method for starting up a newly built catalytic cracking unit or a modified catalytic cracking unit.

[0230] According to one embodiment of the fourth series of uses of the third aspect of the present invention, the fourth series of composite start-up catalysts according to the first aspect are used in a newly built catalytic cracking unit or in a start-up method of a modified catalytic cracking unit; preferably, the catalytic cracking unit is a catalytic cracking unit that produces more propylene and gasoline.

[0231] According to the fourth aspect of the present invention, the present invention also provides a method for starting up a catalytic cracking or catalytic cracking unit, which includes introducing crude oil into the unit during the startup stage of the catalytic cracking or catalytic cracking unit and contacting it with the fluidized composite startup catalyst according to the present invention to carry out catalytic cracking or catalytic cracking reaction.

[0232] According to the first series of start-up methods according to the fourth aspect of the present invention, a start-up method for a heavy oil catalytic cracking unit is provided. During the start-up phase of the catalytic cracking unit, the heavy oil is introduced into a catalytic cracking reactor and brought into contact with the first series of composite start-up catalysts according to the first aspect of the present invention in a fluidized state to carry out a catalytic cracking reaction.

[0233] According to one embodiment of the first series of start-up methods of the fourth aspect above, the start-up process further includes the step of adding the catalytic cracking catalyst used in normal production of the device. According to one embodiment, the catalytic cracking catalyst used in normal production of the device contains 20 to 60% by weight of a shape-selective molecular sieve, 30 to 80% by weight of a carrier, and 5 to 10% by weight of other molecular sieves. The carrier is, for example, one or more of alumina, silica, silica-alumina, clay, phosphate aluminum gel, zirconium oxide, and titanium oxide. The shape-selective molecular sieve is, for example, a ZSM-5 molecular sieve. The other molecular sieve is, for example, one or more of a Y-type molecular sieve and a β-molecular sieve.

[0234] According to the second series of start-up methods according to the fourth aspect of the present invention, a start-up method for a high-density heavy oil catalytic cracking unit is provided. During the start-up stage of the catalytic cracking unit, the high-density heavy oil is introduced into a catalytic cracking reactor and brought into contact with the fluidized second series of composite start-up catalysts according to the first aspect of the present invention to carry out a catalytic cracking reaction.

[0235] According to one embodiment of the first and second series start-up methods of the fourth aspect of the present invention, the coke factor of the composite start-up catalyst is ≤0.070, for example, 0.02-0.07, and / or the propylene factor of the composite start-up catalyst is ≥0.44, for example, 0.44-0.8. The method wherein the propylene factor is ≥0.44 is particularly suitable for the start-up of a catalytic cracking catalytic unit. In the present invention, the coke factor and the propylene factor are obtained by "using a fixed fluidized bed evaluation device, the raw material is a heavy oil with a density of 0.87-0.90 g / ml at 20°C or a high-density heavy oil with a density of 0.91-0.95 g / ml at 20°C, the reaction temperature is 570°C, the catalyst-oil weight ratio is 10:1, and the weight hourly space velocity is 10h - 1 " is obtained after the reaction is evaluated; the density is the density measured at 20°C. In the reaction product obtained according to the above method, the coke factor = coke yield / conversion rate; in the reaction product obtained according to the above method, the propylene factor is = propylene yield / liquefied gas yield.

[0236] According to an embodiment of the first series and second series start-up methods of the fourth aspect of the present invention, the method further includes: separating the oil and gas products after the catalytic cracking reaction from the catalyst, introducing the catalyst into the regenerator for regeneration after stripping, and then circulating it to the catalytic cracking reactor device for reaction, and introducing the oil and gas products into the subsequent oil and gas separation device for separation. Preferably, the longitudinal cross-section of the reactor of the catalytic cracking device has an inverted trapezoidal structure.

[0237] According to the third series of start-up methods of the fourth aspect of the present invention, a start-up method for a heavy oil catalytic cracking unit is provided, wherein during the start-up phase of the catalytic cracking unit, the heavy oil is introduced into the catalytic cracking unit and brought into contact with the fluidized third series of composite start-up catalysts according to the first aspect to carry out a catalytic cracking reaction; preferably, the heavy oil is an intermediate base heavy oil.

[0238] According to the third series of start-up methods of the fourth aspect of the present invention, during the start-up process, the step of adding the catalytic cracking catalyst normally used in the production of the device is further included. Preferably, the catalytic cracking catalyst normally used in the production of the device contains 20-60% by weight of Y-type molecular sieve, 30-80% by weight of a carrier, and 5-10% by weight of other molecular sieves. The carrier is, for example, one or more of alumina, silica, silica-alumina, clay, phosphatic aluminum gel, zirconium oxide, and titanium oxide. The shape-selective molecular sieve is, for example, ZSM-5 molecular sieve. The other molecular sieve is, for example, one or more of ZSM-5 molecular sieve and β molecular sieve.

[0239] The third series of composite startup catalysts according to the first aspect of the present invention are used during the startup phase of a catalytic cracking unit, including shutdowns for maintenance, new unit start-up, rapid replacement of equalizer poisoning, and abnormal unit loss. This allows for efficient and stable startup and smooth replacement of the unit. For example, using this startup catalyst can rapidly achieve expected values ​​for reaction indicators of the catalytic cracking unit, such as product distribution, significantly shortening the startup time.

[0240] According to the preparation method of the third series of composite start-up catalysts of the first aspect of the present invention, a catalytic cracking balancer is compounded with a specific component B catalyst to obtain a start-up catalyst having the aforementioned properties, and since the balancer is used for preparation, the cost of the start-up catalyst of the present invention is relatively low.

[0241] According to the third series of start-up methods of the fourth aspect of the present invention, by using the start-up catalyst, it is possible to avoid using a balance agent with a low degree of match with the target device to start directly before adding the catalytic cracking catalyst used in normal production of the device, which would lead to fluidization problems of the device and an increase in dry gas and coke, affecting the normal fluidization of the device and the rapid compliance of product distribution. Because the start-up catalyst has a good ability to tolerate fluctuations, after replacing a large amount of fresh catalyst, the device can achieve a new steady state more quickly at a higher replacement amount than the existing start-up catalyst, thereby making the start-up efficient and stable.

[0242] According to the fourth series of start-up methods of the fourth aspect of the present invention, a start-up method for a high-density heavy oil catalytic cracking unit is provided, wherein during the start-up phase of the catalytic cracking unit, the heavy oil is introduced into the catalytic cracking unit and brought into contact with the fluidized fourth series composite start-up catalyst according to the first aspect to carry out a catalytic cracking reaction; preferably, the heavy oil is hydrogenated heavy oil.

[0243] According to an embodiment of the fourth series of start-up methods of the fourth aspect above, the catalyst is used in the start-up method of a catalytic cracking device for producing more propylene and gasoline, such as a MIP series technology device, especially a MIP-CGP catalytic cracking device.

[0244] The fourth series of composite start-up catalysts according to the first aspect described above can be used for the startup of a plant that produces more gasoline and propylene, such as during the startup phase of a MIP series technology plant, particularly a MIP-CGP catalytic cracking unit. This includes, but is not limited to, the startup of a plant after a shutdown for maintenance, the startup of a new plant, rapid replacement of equalizer after poisoning, or supplemental catalyst for abnormal agent loss. This catalyst can achieve efficient and stable plant startup, ensuring rapid and stable operation. For example, prior art MIP plants, such as MIP-CGP catalytic cracking units, often require a month or more to achieve stable operation and meet design goals when using equalizers for startup. However, the catalyst of the present invention can achieve stable operation and meet design goals within a week.

[0245] In particular, the present invention provides the following four sets of technical solutions, wherein:

[0246] The first technical solution includes:

[0247] 1. A start-up catalyst for a catalytic cracking device, comprising a component A catalyst and a component B catalyst, wherein the content of the component A catalyst is 15 to 95% by weight, and the content of the component B catalyst is 5 to 85% by weight, based on the dry weight of the start-up catalyst.

[0248] The component B catalyst is a fresh catalyst, and its active component includes a hollow multi-level porous ZSM-5 nanocrystalline material. The content of the hollow multi-level porous ZSM-5 nanocrystalline material is 5 to 15% by weight of the component B catalyst on a dry basis.

[0249] The cracking activity of the component A catalyst is 55-65.

[0250] 2. The start-up catalyst according to item 1 above, wherein the specific surface area of ​​the catalyst of component A is ≥ 100 m 2 / g; nickel content ≤6000μg / g, vanadium content ≤3000μg / g, rare earth element content ≤10000μg / g; the component A is a catalytic cracking balance agent and / or a treated catalytic cracking balance agent.

[0251] 3. The start-up catalyst according to items 1-2 above, wherein the component A catalyst has the following particle size distribution: the content of particles with a particle size of 0-20 μm is ≤3.0% by volume, the content of particles with a particle size of 0-40 μm is ≤18.0% by volume, the content of particles with a particle size of 0-149 μm is ≥90.0% by volume, and the average particle size is 60.0-80.0 μm; the content of particles with a particle size of 0-20 μm of the component B catalyst is ≤2.0% by volume, the content of particles with a particle size of 0-40 μm is ≤18.0% by volume, the content of particles with a particle size of 0-149 μm is ≥90.0% by volume, and the average particle size is 60.0-85.0 μm.

[0252] 4. The start-up catalyst according to items 1 to 3 above, wherein the nickel content in the start-up catalyst is ≤4000 μg / g, the vanadium content is ≤2500 μg / g, the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume%, and the average particle size is 65.0 to 85.0 μm.

[0253] 5. The start-up catalyst according to items 1-4 above, wherein the component B catalyst has an apparent bulk density of 0.8 to 0.94 g / mL and an abrasion index ≤ 2; and / or the start-up catalyst has an apparent bulk density of 0.9 to 0.94 g / mL and an abrasion index ≤ 2.

[0254] 6. The start-up catalyst according to items 1 to 5 above, wherein the component B catalyst further comprises a carrier, and the carrier content is 85 to 95% by weight of the component B catalyst on a dry basis, and the carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0255] 7. The start-up catalyst according to items 1 to 6 above, wherein the hollow multi-level porous ZSM-5 nanocrystalline material has a hollow structure, an average grain size of 0.2-3.0 μm, a ratio of the bulk silicon-aluminum molar ratio to the surface silicon-aluminum molar ratio of 1.0-1.5, and a total specific surface area of ​​340-420 m 2 / g, mesopore specific surface area is 40-150m 2 / g, the N2 adsorption-desorption curve presents an H4-type hysteresis loop; preferably, the relative crystallinity of the hollow multi-level pore ZSM-5 nanocrystalline material is 75-95%.

[0256] 8. The start-up catalyst according to items 1-7 above, wherein the coke factor of the start-up catalyst is ≤0.070, the propylene factor is ≥0.44, and the cracking activity is preferably 58-62.

[0257] 9. A method for preparing the start-up catalyst of items 1 to 8 above, comprising synthesizing a component B catalyst by mixing a component A catalyst and a component B catalyst, wherein the preparation method of the component B catalyst comprises:

[0258] The matrix carrier, the hollow multi-level pore ZSM-5 nanocrystalline material and water are slurried, spray-dried, and optionally calcined.

[0259] 10. The method according to item 9 above, wherein the preparation method of the component B catalyst further comprises exchanging the catalyst microspheres obtained by spray drying with ammonium and optionally washing, wherein the ammonium exchange causes the Na2O content in the obtained component B catalyst to be less than 0.15 wt %; in one embodiment, the catalyst microspheres, ammonium salt and water are mixed in a weight ratio of 1:(0.1-1):(5-15) to perform ammonium exchange; in one embodiment, the conditions of the ammonium exchange include: a temperature of 50-100°C and a time of 0.5-2 hours, and the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate.

[0260] 11. The method according to items 9-10 above, wherein the catalyst of component A is a balance agent, and the balance agent is a catalytic cracking balance agent and / or a catalytic cracking balance agent, wherein the catalytic cracking balance agent is a balance agent produced by a catalytic cracking unit, and the catalytic cracking balance agent is a balance agent produced by a catalytic cracking unit;

[0261] In one embodiment, the component A catalyst is a treated balance agent obtained by treating the balance agent; the treatment includes: demetallization treatment and particle size adjustment treatment, the demetallization treatment is such as chemical demetallization treatment and / or physical demetallization treatment such as magnetic separation, the particle size adjustment treatment is such as gas purging to blow out fine powder therein, or sieving.

[0262] The second technical solution includes:

[0263] 1. A composite catalyst comprising:

[0264] (1) 20 to 90 weight percent of component A catalyst, wherein the cracking activity of the component A catalyst is 55 to 65,

[0265] (2) 5 to 65 weight percent of component B catalyst, wherein the main active component of the component B catalyst is ZSM-5 molecular sieve,

[0266] (3) 5 to 15 weight percent of component C catalyst, wherein the component C catalyst contains 2 to 10 weight percent of a modified metal oxide, and the modified metal is an alkaline earth metal.

[0267] 2. The composite catalyst according to item 1 above, wherein the component A catalyst is a balancer and / or a treated balancer obtained by treating the balancer; the treatment may include a demetallization treatment and / or a particle size adjustment treatment;

[0268] The specific surface area of ​​the component A catalyst is ≥100m 2 / g; nickel content ≤6000μg / g, vanadium content ≤3000μg / g, rare earth elements ≤10000μg / g; for example, the specific surface area of ​​the component A catalyst is 100-200m 2 / g; nickel content is 500-6000μg / g, vanadium content is 50-3000μg / g, rare earth element content is 500-10000μg / g; the cracking activity of the component A catalyst is preferably 57-63.

[0269] 3. The composite catalyst according to items 1-2 above, wherein the particle size distribution of the component A catalyst is: the content of particles with a particle size of 0 to 20 μm is ≤3.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume, and the average particle size is 60.0 to 80.0 μm.

[0270] 4. The composite catalyst according to items 1-3 above, wherein the catalyst component B has an apparent bulk density of 0.80 to 0.94 g / mL and an abrasion index of ≤2.0;

[0271] Preferably, in the component B catalyst, the content of particles with a particle size of 0-20 μm is ≤2.0% by volume, the content of particles with a particle size of 0-40 μm is ≤18.0% by volume, the content of particles with a particle size of 0-149 μm is ≥90.0% by volume, and the average particle size is 60.0-85.0 μm.

[0272] 5. The composite catalyst according to items 1 to 4 above, wherein the component B catalyst comprises: 5 to 15 wt% ZSM-5 molecular sieve on a dry basis, and 85 to 95 wt% matrix support on a dry basis;

[0273] The matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0274] 6. The composite catalyst according to items 1-5 above, wherein the component C catalyst comprises 2-10 wt% of a modifying metal oxide and 90-98 wt% of a carrier; the metal oxide is an alkaline earth metal oxide; the carrier is selected from one or more of natural clay, an alumina carrier, and a silica carrier; the alumina carrier is, for example, one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina, and activated alumina; and the silica carrier is, for example, one or more of neutral silica sol, acidic silica sol, or alkaline silica sol.

[0275] 7. The composite catalyst according to items 1-6 above, wherein the component C catalyst can be obtained by modifying inert microspheres with the modified metal element compound, or by adding the modified metal element compound to an inert microsphere precursor, slurrying the mixture, and then spray drying the mixture; the modified metal element compound is, for example, one or more of magnesium nitrate, barium nitrate, strontium nitrate, or radium nitrate.

[0276] 8. The composite catalyst according to items 1 to 7 above, wherein the apparent bulk density of the composite catalyst is 0.90 to 0.94 g / mL, and the wear index of the composite catalyst is ≤2.0; in the composite catalyst: the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume, and the average particle size is 65.0 to 85.0 μm.

[0277] 9. The composite catalyst according to items 1 to 8 above, wherein, in the composite catalyst: nickel content ≤ 4000 μg / g, vanadium content ≤ 2500 μg / g, for example, nickel content, vanadium content.

[0278] 10. The composite catalyst according to items 1 to 9 above, wherein the cracking activity of the composite catalyst is 58 to 62, the coke factor of the composite catalyst is ≤0.070, and the propylene factor of the composite catalyst is ≥0.44.

[0279] 11. The composite catalyst according to items 1-10 above, wherein the content of the catalyst of component A is , the content of the catalyst of component B is , and the content of the catalyst of component C is .

[0280] 12. A method for preparing the composite catalyst of items 1-11 above, comprising physically blending a component A catalyst, a component B catalyst, and a component C catalyst, wherein the preparation method of the component B catalyst comprises: slurrying a slurry of a matrix support, a ZSM-5 molecular sieve, and optionally water, spray drying to obtain first catalyst particles, and optionally calcining;

[0281] The preparation method of the component C catalyst comprises: mixing the matrix support with optional water for slurrying, spray drying to obtain second catalyst particles, modifying the modified metal by impregnation, drying, and calcining; or

[0282] The preparation method of the component C catalyst comprises: mixing and slurrying a matrix carrier, a modified metal salt solution and optionally water, spray drying to obtain third catalyst particles, and optionally calcining.

[0283] The matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier.

[0284] 13. The method according to item 12 above, wherein the preparation method of the component B catalyst or the component C catalyst further comprises: mixing the catalyst particles obtained by spray drying, an ammonium salt and water to perform ammonium exchange, and optionally washing the catalyst microspheres to make the Na2O content less than 0.15 wt%; the catalyst particles obtained by spray drying are the first catalyst particles, the second catalyst particles or the third catalyst particles.

[0285] 14. A method for starting up a high-density heavy oil catalytic cracking unit, comprising: introducing heavier heavy oil into a catalytic cracking reactor during the start-up phase of the catalytic cracking unit to contact the oil with a fluidized catalyst for a catalytic cracking reaction; separating the oil and gas products from the cracking reaction from the catalyst; introducing the catalyst into a regenerator for regeneration after passing through the gas, and then circulating it to the catalytic cracking reactor for reaction; and introducing the oil and gas products into a subsequent oil-gas separation unit for separation, wherein the catalyst is the composite catalyst described in items 1-10 above.

[0286] The third technical solution includes:

[0287] 1. A catalyst for starting a catalytic cracking unit, having the following particle size distribution: the content of particles with a particle size of 0 to 20 μm is ≤ 2.0% by volume, the content of particles with a particle size of 0 to 40 μm is ≤ 18.0% by volume, the content of particles with a particle size of 0 to 149 μm is ≥ 90.0% by volume, and the average particle size is 65.0 to 85.0 μm.

[0288] The start-up catalyst has a nickel content of ≤5000 μg / g, a vanadium content of ≤3500 μg / g, and an iron content of ≤4500 μg / g.

[0289] The start-up catalyst has the following characteristics: coke factor ≤ 0.140, gasoline factor ≥ 0.420,

[0290] Preferably, the cracking activity of the start-up catalyst is 55-65.

[0291] 2. A catalytic cracking unit startup catalyst, comprising a component A catalyst and a component B catalyst, wherein the content of the component A catalyst is 15-95% and the content of the component B catalyst is 5-85% based on the dry weight of the startup catalyst, wherein:

[0292] The component A catalyst is a catalytic cracking balance agent and / or a treated catalytic cracking balance agent;

[0293] The component B catalyst is a fresh catalyst, and its active component includes a modified small-grain Y-type molecular sieve material. The content of the modified small-grain Y-type molecular sieve material is 5 to 15% by weight of the component B catalyst on a dry basis;

[0294] Preferably, the cracking activity of the component A catalyst is 55-65.

[0295] 3. The start-up catalyst according to item 2, wherein the specific surface area of ​​the catalyst of component A is ≥100m 2 / g; nickel content ≤6000μg / g, vanadium content ≤4000μg / g, iron content ≤5000μg / g, rare earth element content ≥10000μg / g;

[0296] Preferably, the component A catalyst has the following particle size distribution: the content of particles with a particle size of 0 to 20 μm is ≤3.0% by volume, the content of particles with a particle size of 0 to 40 μm is ≤18.0% by volume, the content of particles with a particle size of 0 to 149 μm is ≥90.0% by volume, and the average particle size is 60.0 to 80.0 μm;

[0297] Preferably, the content of particles with a size of 0-20 μm in the component B catalyst is ≤2.0% by volume, the content of particles with a size of 0-40 μm is ≤18.0% by volume, the content of particles with a size of 0-149 μm is ≥90.0% by volume, and the average particle size is 60.0-85.0 μm.

[0298] 4. The start-up catalyst according to item 1, 2 or 3, wherein the nickel content in the start-up catalyst is ≤5000 μg / g, the vanadium content is ≤3500 μg / g, the iron content is ≤4500 μg / g, the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume%, and the average particle size is 65.0 to 85.0 μm.

[0299] 5. The start-up catalyst according to item 2 or 4, wherein the component B catalyst has an apparent bulk density of 0.80 to 0.94 g / mL and an abrasion index ≤ 2.0; and / or the start-up catalyst has an apparent bulk density of 0.90 to 0.94 g / mL and an abrasion index ≤ 2.0.

[0300] 6. The start-up catalyst according to item 2 or 5, wherein the component B catalyst further comprises a carrier, and the carrier content is 85 to 95% by weight of the component B catalyst on a dry basis, and the carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier can be one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0301] 7. The start-up catalyst according to item 2, wherein the modified small-grain Y-type molecular sieve material has: a RE2O3 content of 0 to 18% by weight, a Na2O content of no more than 1% by weight, a unit cell constant of 2.43 to 2.47 nm, a non-framework aluminum content of no more than 30% of the total aluminum content, a ratio of B acid to L acid of no less than 2.5, an external surface acidity of 150 to 300 μmol / g, and a total specific surface area of ​​580 to 650 m 2 ·g -1 , the average grain size is 0.5~1.0μm.

[0302] 8. The start-up catalyst according to item 7, wherein the relative crystallinity of the modified small-grain Y-type molecular sieve material is 45-65% and / or the lattice collapse temperature is not lower than 1030°C, the coke factor of the start-up catalyst is ≤0.140, and the gasoline factor of the start-up catalyst is ≥0.420.

[0303] 9. A method for preparing the start-up catalyst according to any one of items 1 to 8, comprising synthesizing a component B catalyst by mixing a component A catalyst and a component B catalyst, wherein the preparation method of the component B catalyst comprises:

[0304] The carrier and / or carrier precursor / modified small-crystal Y-type molecular sieve material and water are mixed and beaten to form a slurry, which is spray-dried and optionally calcined.

[0305] 10. The method according to item 9, wherein the preparation method of the component B catalyst further comprises exchanging the catalyst microspheres obtained by spray drying with ammonium, wherein the ammonium exchange causes the Na2O content in the obtained component B catalyst to be less than 0.15 wt %; in one embodiment, the catalyst microspheres, ammonium salt and water are mixed in a weight ratio of 1:(0.1-1):(5-15) to perform ammonium exchange; in one embodiment, the conditions of the ammonium exchange include: a temperature of 50-100°C and a time of 0.5-2 hours, and the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate.

[0306] 11. The method according to item 9, wherein the catalyst of component A is a balance agent, and the balance agent is a catalytic cracking balance agent, wherein the catalytic cracking balance agent is a balance agent produced by a catalytic cracking unit;

[0307] And / or, the component A catalyst is a treated balance agent obtained by treating the balance agent produced by a catalytic cracking unit; the treatment includes: demetallization treatment and / or particle size adjustment treatment, the demetallization treatment may be a chemical demetallization treatment and / or a physical demetallization treatment such as magnetic separation, the particle size adjustment treatment may be, for example, gas purging to remove fine powder, or sieving.

[0308] 12. Use of the start-up catalyst according to any one of items 1 to 8 in the start-up of a new catalytic cracking unit or in the replenishment of the equalizer after poisoning or abnormal agent leakage, such as the start-up after the unit is shut down for maintenance or the start-up of a new catalytic cracking unit.

[0309] The fourth technical solution includes:

[0310] 1. A catalyst comprising a component A catalyst, a component B catalyst and a component C catalyst, wherein, based on the dry weight of the catalysts, the content of the component A catalyst is 20-90%, the content of the component B catalyst is 5-65%, and the content of the component C catalyst is 5-15%, wherein the main active components of the component B catalyst include a modified small-grain Y-type molecular sieve and an optional ZSM-5 molecular sieve material, and the component C catalyst contains a carrier and a metal oxide, and the content of the metal oxide in the component C catalyst is 2-10 weight %.

[0311] 2. The catalyst according to item 1, wherein the catalyst of component A is a catalytic cracking catalyst, and the specific surface area of ​​the catalyst of component A is ≥100m 2 / g; nickel content ≤6000μg / g, vanadium content ≤5000μg / g, iron content ≤5000μg / g, sodium content ≤3000μg / g, calcium content ≤3000μg / g, Y-type molecular sieve crystallinity ≥20.0%, ZSM-5 molecular sieve crystallinity ≥2.0%; the particle size of the component A catalyst is 0-20μm ≤3.0% by volume, the particle size of 0-40μm is ≤18.0% by volume, the particle size of 0-149μm is ≥90.0% by volume, and the average particle size is 60.0-80.0μm.

[0312] 1. The catalyst according to item 1 or 2, wherein the cracking activity of the catalyst of component A is 55 to 65;

[0313] Preferably, the component B catalyst has an apparent bulk density of 0.8 to 0.94 g / mL and an abrasion index of ≤2.0;

[0314] The particle size of the component B catalyst is 0-20 μm ≤ 2.0% by volume, the particle size of 0-40 μm ≤ 18.0% by volume, the particle size of 0-149 μm ≥ 90.0% by volume, and the average particle size is 60.0-85.0 μm.

[0315] 2. The catalyst according to item 1, wherein the Component B catalyst further comprises a matrix support and an active component, wherein, based on the dry weight of the Component B catalyst, the matrix support comprises 85-95% by weight of the Component B catalyst on a dry basis, and the active component comprises 5-15% by weight of the Component B catalyst on a dry basis; the active component of the Component B catalyst is a modified small-grain Y-type molecular sieve and an optional ZSM-5 molecular sieve; wherein the ZSM-5 molecular sieve can be, for example, a conventional ZSM-5 molecular sieve, a hierarchical ZSM-5 molecular sieve, a metal-modified hierarchical ZSM-5 molecular sieve, or a hollow mesoporous ZSM-5 molecular sieve;

[0316] Optionally, the weight ratio of the modified small-grain Y-type molecular sieve to the ZSM-5 molecular sieve is greater than 2;

[0317] Optionally, the average grain size of the modified small-grain Y-type molecular sieve is 300-700 nm; the rare earth content of the modified small-grain Y-type molecular sieve may be 1-20 wt %; the silicon-aluminum ratio is, for example, 5.1-10 in terms of SiO2 / Al2O3 molar ratio;

[0318] The matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

[0319] 3. The catalyst according to item 1, wherein the metal oxide loading of the component C catalyst is 2 to 10% by weight, and the metal oxide of the component C catalyst can be one or more of magnesium oxide, barium oxide, strontium oxide, and radium oxide.

[0320] 4. The catalyst according to item 1, wherein the catalyst component C can be obtained by modifying inert microspheres with metal elements, or by adding metal elements to a catalyst precursor and then spray drying;

[0321] For example, the component C catalyst is prepared by any one or more of the following methods:

[0322] Method 1, which comprises: slurrying and spray drying the matrix carrier, impregnating the matrix carrier with a metal salt solution for metal modification, drying, and calcining.

[0323] Method 2, which comprises: uniformly mixing the matrix carrier and the metal salt solution, spray drying, and optionally roasting. The metal salt may be one or more of magnesium nitrate, barium nitrate, strontium nitrate, or radium nitrate.

[0324] 5. The catalyst according to item 1, wherein the apparent bulk density of the catalyst is 0.90 to 0.94 g / mL and the attrition index of the catalyst is ≤2.0;

[0325] The catalyst has a nickel content of ≤5000 μg / g, a vanadium content of ≤4000 μg / g, an iron content of ≤4000 μg / g, a sodium content of ≤2000 μg / g, and a calcium content of ≤2000 μg / g;

[0326] The particle size distribution of the catalyst is as follows: particles with a particle size of 0 to 20 μm are ≤ 2.0% by volume, particles with a particle size of 0 to 40 μm are ≤ 18.0% by volume, particles with a particle size of 0 to 149 μm are ≥ 90.0% by volume, and the average particle size is 65.0 to 85.0 μm;

[0327] Preferably, the catalyst has a cracking activity of 55 to 65, a coke factor ≤ 0.125, such as 0.05 to 0.12, a gasoline factor ≥ 0.430, such as 0.43 to 0.48, and a propylene factor ≥ 0.420, such as 0.42 to 0.47.

[0328] 6. The catalyst according to any one of items 1 to 7, wherein the preparation method of the component B catalyst comprises: beating a slurry of a matrix support, a small-grain Y-type molecular sieve, a ZSM-5 molecular sieve, and water, spray drying, and optionally calcining;

[0329] Optionally, the preparation method of the component B catalyst and / or the component C catalyst further includes: mixing the catalyst particles obtained by the spray drying, an ammonium salt and water in a weight ratio of 1:(0.1-1):(5-15) to perform ammonium exchange, and optionally washing, so that the Na2O content in the component B catalyst and the component C catalyst is less than 0.15 weight% respectively; the conditions of the ammonium exchange include: a temperature of 50-100°C and a time of 0.5-2 hours; and the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate.

[0330] 7. The catalyst according to item 1, wherein the catalyst is prepared by physically mixing the component A catalyst, the component B catalyst and the component C catalyst in a certain proportion.

[0331] 8. Use of the catalyst according to any one of items 1 to 9 in a catalytic cracking unit for producing more propylene and gasoline, such as a MIP catalytic cracking unit. The application includes: new operation of the unit after modification, rapid replacement of the balance agent after poisoning, or replenishment of the catalyst when the unit is abnormally running, which can achieve efficient and stable operation or rapid replacement and replenishment of the balance agent.

[0332] The composite startup catalyst provided by the present invention is used during the startup phase of a catalytic cracking or catalytic cracking unit, including during shutdowns for maintenance or the start-up of a new unit, to achieve efficient and stable startup of the unit. For example, using the composite startup catalyst can rapidly achieve expected values ​​for reaction indicators of the catalytic cracking or catalytic cracking unit, such as product distribution, significantly shortening the startup time.

[0333] The method for preparing the composite start-up catalyst provided by the present invention uses a catalytic cracking or catalytic cracking balance agent to compound with a specific component B catalyst and an optional component C catalyst to obtain a composite start-up catalyst with the properties. In addition, since the balance agent is used for preparation, the cost of the catalyst is low.

[0334] The method for starting up a catalytic cracking or catalytic cracking device provided by the present invention can avoid the shortcomings of the existing composite startup catalyst, such as large conversion load, high coke yield, and difficulty in stabilization, caused by high activity and high coke factor, before adding the catalytic cracking or catalytic cracking catalyst used in normal production of the device, by using the composite startup catalyst. By combining lower activity with a lower coke factor and further combining a higher propylene factor during the startup process of the catalytic cracking or catalytic cracking device, the device can be quickly stabilized before adding the catalyst used in normal production. Since the composite startup catalyst has good fluctuation tolerance, after replacing a large amount of fresh catalyst, the device can achieve a new steady state more quickly at a higher replacement amount than the existing composite startup catalyst, thereby making the startup efficient and stable.

[0335] The start-up method provided by the present invention can greatly shorten the start-up time, for example, quickly achieve the expected product distribution, and complete the start-up within about a week.

[0336] Other features and advantages of the present invention will be described in detail in the following embodiments.

[0337] Example

[0338] The following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0339] The following Examples 1 and 2 are used to illustrate the implementation of the first series of technical solutions according to the first aspect of the present invention; and Comparative Examples 1-2 are used to illustrate the advantages of the technical solutions according to the present invention.

[0340] The raw materials used in the examples and comparative examples of the present invention are:

[0341] Alumina sol: product from Sinopec Catalyst Co., Ltd. Qilu Branch, Al2O3 content 21.5% by weight.

[0342] Silica sol: a product from Qingdao Junqiang New Materials Co., Ltd., with a SiO2 content of 30% by weight and a pH of 9.5.

[0343] Pseudo-boehmite: product from Shandong Aluminum Company, Al2O3 content 62% by weight.

[0344] Kaolin: product from China Kaolin Co., Ltd., solid content 76% by weight.

[0345] Hollow multi-level porous ZSM-5 nanocrystalline material 1: its TEM image is shown in FIG1 , and its properties are shown in Table 2.

[0346] Modified small-grain Y-type molecular sieve 1: Its SEM image is shown in Figure 2, with an average grain size of about 500 nm. Its properties are shown in Table 11. Its source: Qilu Branch of Sinopec Catalyst Co., Ltd. Its silicon-aluminum ratio (SiO2 / Al2O3 molar ratio) is 5.2, and the modifying element is lanthanum, with a content of 12 weight%.

[0347] The balance agents P1 and P2 used were balance agents produced in a catalytic cracking unit, and their properties are shown in Table 1.

[0348] The content of metal elements (such as nickel and vanadium) or rare earth elements in the balancing agent is determined according to the NB / SH / T0863 Guide for the Determination of Chemical Elements in Sulfurized Catalytic Cracking Catalysts by X-ray Fluorescence Spectrometry or the HG / T5765 Determination of Metal Elements in Catalytic Cracking Catalysts.

[0349] The following Examples 1-1, 1-2 and 2 and Comparative Examples 1-4 are used to illustrate the technical effects of the first series of start-up catalysts according to the first aspect of the present invention:

[0350] Example 1-1

[0351] The start-up catalyst used in this embodiment includes:

[0352] (1) Component A Catalyst A1:

[0353] Its physical properties are shown in Table 1. It is obtained by the following method: the balance agent from the catalytic cracking DCC unit is subjected to physical cyclone treatment (the spent catalyst is screened through a cyclone separator to separate the fine powder) to achieve a certain particle size requirement; and then subjected to chemical demetallization treatment (the balance agent is contacted with a sulfuric acid solution to react with harmful metals such as vanadium, nickel, iron, and sodium deposited on the balance agent, partially removing these harmful metals to reduce its toxicity) to achieve a certain metal content.

[0354] (2) Component B catalyst B1-1:

[0355] Pseudoboehmite and water were mixed uniformly, and concentrated hydrochloric acid with a concentration of 36 wt% was added under stirring, and the acid-aluminum ratio (the molar ratio of HCl to pseudoboehmite calculated as Al2O3) was 0.2; the resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry; the aged pseudoboehmite slurry had an alumina content of 12 wt%. A hollow hierarchical ZSM-5 nanocrystalline material, aluminum sol, silica sol, kaolin, the aged pseudo-boehmite slurry, and deionized water were uniformly mixed to form a slurry with a solid content of 30% by weight. The slurry was then spray-dried to obtain component B catalyst particles. The component B catalyst particles were calcined at 550°C for 4 hours. The calcined component B catalyst particles were exchanged at 80°C for 1 hour in a weight ratio of component B catalyst particles: ammonium salt: H2O = 1:1:10, filtered, and the exchange and filtration process was repeated once. The ammonium salt was ammonium chloride, and the resulting component B catalyst B1-1 had a sodium oxide content of less than 0.15% by weight. The properties of the hollow hierarchical ZSM-5 nanocrystalline material are shown in Table 2.

[0356] The catalyst A1 of component A and the catalyst B1-1 of component B were mixed uniformly in a certain ratio (85:15 by weight) to obtain the start-up catalyst D1-1 of Example 1. The properties are shown in Table 3.

[0357] Example 1-2

[0358] In this embodiment:

[0359] (1) The component A catalyst A1 used is the same as that in Example 1-1;

[0360] (2) The component B catalyst B1-2 used was prepared in the same manner as the component B catalyst B1-1 in Example 1-1, but the content of the active component in the component B catalyst B1-2 was different from the content of the active component in the component B catalyst B1-1 in Example 1-1.

[0361] The catalyst A1 of component A and the catalyst B1-2 of component B were mixed uniformly in a certain ratio (55:45 by weight) to obtain the start-up catalyst D1-2 of Example 1. The properties are shown in Table 3.

[0362] Example 2

[0363] The start-up catalyst used in this embodiment includes:

[0364] (1) Component A Catalyst A2:

[0365] Its physical properties are shown in Table 1. It is obtained by subjecting a balance agent from a catalytic cracking unit (different from the DCC balance agent in Example 1) to a cyclone treatment to achieve a certain particle size, and then to a chemical demetallization treatment to achieve a certain metal content.

[0366] (2) Component B catalyst B2:

[0367] Pseudoboehmite and water were uniformly mixed, and concentrated hydrochloric acid at a concentration of 36% by weight was added with stirring, with an acid-to-aluminum ratio of 0.2 (molar ratio of HCl to pseudoboehmite calculated as Al2O3). The resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudoboehmite slurry had an alumina content of 12% by weight. Hollow hierarchical ZSM-5 nanocrystalline material, alumina sol, kaolin, the aged pseudoboehmite slurry, and deionized water were uniformly mixed to form a slurry with a solid content of 30% by weight, which was spray-dried to obtain component B catalyst particles. The component B catalyst particles were calcined at 550°C for 4 hours. The calcined catalyst particles were exchanged at 80°C for 1 hour in a weight ratio of component B catalyst particles: ammonium salt: H2O = 1:1:10, filtered, and the exchange and filtration process was repeated once, followed by drying. The ammonium salt was ammonium chloride, and the resulting component B catalyst B2 had a sodium oxide content of less than 0.15% by weight. The properties of the hollow multi-level porous ZSM-5 nanocrystalline material are shown in Table 2.

[0368] The component A catalyst A2 and the component B catalyst B2 were mixed uniformly in a certain proportion to obtain the composite start-up catalyst D2 of Example 2. The properties are shown in Table 3.

[0369] Comparative Example 1

[0370] The start-up catalyst used in this comparative example 1 is a conventional balancing agent P1 commonly used in the prior art, and its physical properties are shown in Table 1.

[0371] Comparative Example 2

[0372] The start-up catalyst used in this comparative example 2 is a conventional balancing agent P2 commonly used in the prior art, and its physical properties are shown in Table 1.

[0373] Comparative Example 3

[0374] The start-up catalyst in Comparative Example 3 only contained the Component A catalyst A1 used in Example 1, and did not contain the Component B catalyst. The physical properties of the Component A catalyst A1 are shown in Table 1.

[0375] Comparative Example 4

[0376] The start-up catalyst used in Comparative Example 4 contained only the component B catalyst used in Example 1, and did not contain the component A catalyst A1. The physical properties of the component B catalyst are shown in Table 1.

[0377] Table 1. Catalyst ratios and properties of Examples and Comparative Examples

[0378] Table 2. Properties of hollow hierarchical ZSM-5 nanocrystalline materials

[0379] Table 3. Properties of the composite start-up catalyst

[0380] Performance Testing

[0381] The cracking reaction performance of the catalysts of the embodiment and the comparative example was evaluated in an FFB fixed fluidized bed reactor. The evaluation conditions were a reaction temperature of 570°C, a catalyst-oil ratio of 10, and a space velocity of 10 h - 1 The raw material is paraffin-based heavy oil. The physical properties are shown in Table 4, and the evaluation results are shown in Table 5.

[0382] Table 4. Properties of crude oil

[0383] Table 5. Catalytic performance evaluation results

[0384] The yields mentioned herein are calculated based on the raw material feed.

[0385] Product yield = product yield (weight) / heavy oil feed amount (weight) × 100%

[0386] Coke factor = coke yield (weight) / conversion rate

[0387] Propylene factor = Propylene yield (weight) / Liquefied gas yield

[0388] As shown in Table 5, the composite start-up catalysts provided by Examples 1-1, 1-2, and 2 have suitable cracking activity, a low coke factor, and a high propylene factor. Subsequent start-up tests conducted in industrial plants have shown that the use of the composite start-up catalysts provided by Examples 1-1, 1-2, and 2 can efficiently achieve smooth start-up of the catalytic cracking unit and rapidly optimize product distribution in the initial stage of start-up. However, the use of the balancers P1 and P2 of Comparative Examples 1 and 2 and the start-up catalysts of Comparative Examples 3 and 4, due to their excessively high cracking activity, excessively high coke factor, and / or excessively low propylene factor, cannot achieve rapid and smooth start-up of the catalytic cracking unit in the initial stage of start-up, is not conducive to rapid optimization of product distribution, and prolongs the stabilization time of the unit.

[0389] The following Examples 3-1, 3-2 and 4 and Comparative Examples 3 and 4 are used to illustrate the technical effects and advantages of the second series of composite start-up catalysts according to the first aspect of the present invention.

[0390] The balance agents P3 and P4 used in Comparative Examples 3 and 4 are conventional balance agents produced by catalytic cracking units, and their properties are shown in Table 6.

[0391] The component A catalyst A3 in Examples 3-1 and 3-2 is a treated balance agent obtained by subjecting the catalytic cracking balance agent of the catalytic cracking process to cyclone fractionation and acid demetallization treatment. Its properties are shown in Table 6.

[0392] The component A catalyst A4 in Example 4 is a treated balance agent obtained by subjecting the catalytic cracking balance agent of the catalytic cracking process to cyclone fractionation and acid demetallization treatment. Its properties are shown in Table 6.

[0393] Example 3-1

[0394] The start-up catalyst used in this embodiment includes:

[0395] (1) Component A catalyst A3:

[0396] The balance agent from the catalytic cracking unit was subjected to physical cyclone treatment (using a cyclone separator to separate fine components) to achieve a certain particle size requirement. It was then subjected to chemical demetallization treatment (the catalytic cracking balance agent was contacted with a sulfuric acid solution to react with harmful metals such as vanadium, nickel, iron, and sodium deposited on the balance agent, partially removing these harmful metals to reduce their toxicity) to achieve a certain metal content. Component A catalyst A3 was obtained, and its physical properties are shown in Table 6.

[0397] (2) Component B catalyst B3-1:

[0398] Pseudoboehmite and water were mixed uniformly, and concentrated hydrochloric acid with a concentration of 36 wt% was added under stirring, and the acid-aluminum molar ratio was 0.2 (the molar ratio of HCl to pseudoboehmite calculated as Al2O3); the resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudo-boehmite slurry has an alumina content of 12 wt%; ZRP-1 molecular sieve (a product of Sinopec Catalyst Qilu Branch, having a silicon-aluminum ratio (SiO2 / Al2O3 molar ratio) of 25 and a phosphorus (as P2O5) content of 3.5 wt%), aluminum sol, silica sol, kaolin, the aged pseudo-boehmite slurry, and deionized water are uniformly mixed to form a slurry with a solid content of 30 wt%, and spray-dried to obtain component B catalyst microspheres; the component B catalyst microspheres are calcined at 550°C for 4 hours; the calcined component B catalyst microspheres are exchanged at 80°C for 1 hour in a weight ratio of component B catalyst microspheres: ammonium salt: H2O = 1:1:10, filtered, and the above exchange and filtration processes are repeated once, followed by drying, wherein the ammonium salt is ammonium chloride, to obtain component B catalyst B3-1 having a sodium oxide content of less than 0.15 wt%.

[0399] (3) Component C catalyst C3:

[0400] Pseudoboehmite and water were uniformly mixed, and concentrated hydrochloric acid having a concentration of 36% by weight and an acid-aluminum molar ratio of 0.2 (the molar ratio of HCl to pseudoboehmite calculated as Al2O3) was added with stirring. The resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudoboehmite slurry had an alumina content of 12% by weight. Alumina sol, silica sol, kaolin, the aged pseudoboehmite slurry, and deionized water were uniformly mixed to form a slurry having a solid content of 30% by weight, which was spray-dried and calcined at 550°C for 4 hours to obtain spray-dried microspheres 1.

[0401] Prepare a magnesium nitrate solution by dissolving 18.4 g of magnesium nitrate in 50 g of deionized water. Impregnate the spray-dried microspheres 1 with the magnesium nitrate solution at 50°C for 2 hours, then directly dry and calcine to obtain component C catalyst C3.

[0402] (4) Component A catalyst A3, component B catalyst B3-1, and component C catalyst C3 were mixed uniformly in a certain ratio (80:15:5) (see Table 6 for the ratio) to obtain the composite start-up catalyst D3-1 of Example 1. The properties of the composite start-up catalyst D3-1 are shown in Table 7.

[0403] Example 3-2

[0404] In this embodiment:

[0405] (1) Component A, catalyst A3, is the same as in Example 3-1;

[0406] (2) The component B catalyst B3-2 used was prepared in the same manner as the component B catalyst B3-1 in Example 3-1, but the content of the active component in the component B catalyst B3-2 was different from the content of the active component in the component B catalyst B3-1 in Example 3-1;

[0407] (3) Component B catalyst C3 is the same as that in Example 3-1;

[0408] (4) Component A catalyst A3, component B catalyst B3-2, and component C catalyst C3 were uniformly mixed in a certain ratio (65:30:5) (see Table 6 for the ratio) to obtain the composite start-up catalyst D3-2 of Example 1. The properties of the composite start-up catalyst D3-2 are shown in Table 7.

[0409] Example 4

[0410] (1) Component A catalyst A4:

[0411] The balance agent from the catalytic cracking unit is treated with physical cyclone to achieve a certain particle size requirement; it is then treated with sulfuric acid solution for chemical demetallization to achieve a certain metal content. The physical properties are shown in Table 6.

[0412] (2) Component B catalyst B4:

[0413] Pseudoboehmite and water were mixed uniformly, and concentrated hydrochloric acid at a concentration of 36% by weight was added with stirring, with an acid-to-aluminum ratio of 0.2 (the weight ratio of HCl to pseudoboehmite calculated as Al2O3). The resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudoboehmite slurry had an alumina content of 12% by weight. RMPZ molecular sieve (product of Sinopec Catalyst Co., Ltd., Qilu Branch, with a phosphorus content (calculated as P2O5) of 3.4% by weight, an Fe2O3 content of 2.3% by weight, a silicon-to-aluminum ratio of 25, and a mesopore volume of 0.12 cm3) was added. 3 / g;), aluminum sol, silica sol, kaolin and the aged pseudo-boehmite slurry and deionized water are uniformly mixed to form a slurry with a solid content of 30 wt%, and spray-dried to obtain component B catalyst microspheres; the component B catalyst microspheres are calcined at 550°C for 4 hours; the calcined component B catalyst microspheres are exchanged at 80°C for 1 hour according to a weight ratio of component B catalyst microspheres: ammonium salt: H2O = 1:1:10, and filtered, the above-mentioned exchange and filtration process is repeated once, and the mixture is dried, wherein the ammonium salt is ammonium chloride, to obtain component B catalyst B4, wherein the sodium oxide content is less than 0.15 wt%.

[0414] (3) Component C catalyst C4:

[0415] Pseudoboehmite and water were uniformly mixed, and concentrated hydrochloric acid having a concentration of 36 wt% and an acid-aluminum molar ratio of 0.2 (the molar ratio of HCl to pseudoboehmite calculated as Al2O3) was added with stirring. The resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudoboehmite slurry had an alumina content of 12 wt%. Barium nitrate solution (10.2 g of barium nitrate dissolved in 50 g of deionized water), aluminum sol, silica sol, kaolin, the aged pseudoboehmite slurry, and deionized water were uniformly mixed to form a slurry having a solid content of 30 wt%. The slurry was spray-dried and calcined at 550°C for 4 hours to obtain Component C catalyst C4.

[0416] (4) Component A catalyst A4, component B catalyst B4, and component C catalyst C4 were mixed uniformly in a certain ratio (85:10:5 by weight) to obtain the composite start-up catalyst D4 of Example 4. The properties of the composite start-up catalyst D4 are shown in Table 7.

[0417] Comparative Example 3

[0418] The catalyst in Comparative Example 3 is conventional balancing agent P1, which is the same as the balancing agent used in Comparative Example 1. The physical properties of P1 are shown in Table 6.

[0419] Comparative Example 4

[0420] The catalyst in Comparative Example 4 is conventional balancing agent P2, which is the same as the balancing agent used in Comparative Example 2. The physical properties of P2 are shown in Table 6.

[0421] Table 6. Catalyst ratios and properties of examples and comparative examples

[0422] Table 7. Properties of the composite start-up catalyst

[0423] Performance Testing

[0424] The composite start-up catalyst prepared in the embodiment and the comparative example was used to evaluate its cracking reaction performance in an FFB fixed fluidized bed reactor. The evaluation conditions were a reaction temperature of 570°C, a catalyst-oil ratio of 10:1 by weight, and a weight hourly space velocity of 10 h -1 The raw material is heavy oil. The physical properties are shown in Table 8 and the evaluation results are shown in Table 9.

[0425] Table 8. Heavy oil properties

[0426] Table 9. Catalytic performance evaluation results of start-up agents

[0427] The yields mentioned herein are calculated based on the raw material feed.

[0428] Product yield = product yield (weight) / heavy oil feed amount (weight)

[0429] Coke factor = coke yield (weight) / conversion rate

[0430] Propylene factor = Propylene yield (weight) / Liquefied gas yield

[0431] As shown in Table 9, the composite startup catalyst provided by the present invention has a significantly higher propylene factor and a significantly lower coke factor. Subsequent startup tests conducted on an industrial catalytic cracking unit demonstrated that the composite startup catalysts of Examples 3-1, 3-2, and 4 can efficiently achieve rapid and stable startup of the catalytic cracking unit during the initial startup phase, and can quickly optimize product distribution. However, the balancers P1 and P2 of Comparative Examples 3 and 4, due to their excessively high cracking activity, excessively high coke factor, and excessively low propylene factor, cannot achieve rapid and stable startup of the catalytic cracking unit during the initial startup phase, and cannot quickly optimize product distribution, thus prolonging the unit's stabilization time.

[0432] The following Examples 5 and 6 and Comparative Example 5 are used to illustrate the technical effects of the start-up catalyst of the third series of composite start-up catalysts according to the first aspect.

[0433] In the embodiment, the raw materials used include:

[0434] The component A catalysts 1 and 2 used in Examples 5 and 6 were balancers produced from a catalytic cracking unit, and their properties are shown in Table 10.

[0435] Modified small-grain Y-type molecular sieve 1: Its average grain size is 500 nm, source: Qilu Branch of Sinopec Catalyst Co., Ltd., silicon-aluminum ratio (SiO2 / Al2O3 molar ratio) is 5.2, and the modifying element is lanthanum, with a content of 12 weight%.

[0436] The properties of the modified small-grain Y-type molecular sieve materials used in the Examples and Comparative Examples are shown in Table 11:

[0437] Example 5

[0438] (1) Component A catalyst 1, the physical properties of which are shown in Table 10, is obtained by subjecting the balance agent from the catalytic cracking FCC unit to a physical cyclone treatment (screening the spent catalyst through a cyclone separator to separate the fine powder) to a certain particle size requirement; and then subjecting the balance agent to a chemical demetallization treatment (contacting the balance agent with a sulfuric acid solution to react with harmful metals such as vanadium, nickel, iron, and sodium deposited on the balance agent to partially remove these harmful metals and reduce their toxicity) to a certain metal content.

[0439] (2) Component B catalyst:

[0440] Pseudoboehmite and water are mixed uniformly, and concentrated hydrochloric acid having a concentration of 36 wt% is added with stirring, and the acid-aluminum ratio is 0.2 (the molar ratio of HCl to pseudoboehmite calculated as Al2O3); the resulting mixture is aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry; the aged pseudoboehmite slurry has an alumina content of 12 wt%. The modified small-grain Y-type molecular sieve material 1 (properties are shown in Table 11, a product of Sinopec Catalyst Co., Ltd. Qilu Branch), aluminum sol, silica sol, kaolin and the above-mentioned aged pseudo-boehmite slurry and deionized water were uniformly mixed to form a slurry with a solid content of 30% by weight, and spray-dried to obtain component B catalyst microspheres; the component B catalyst microspheres were calcined at 550°C for 4h; the calcined component B catalyst microspheres were exchanged at 80°C for 1h according to a weight ratio of component B catalyst microspheres: ammonium salt: H2O = 1:1:10, filtered, and the above-mentioned exchange and filtration process was repeated once, and the catalyst was dried, wherein the ammonium salt was ammonium chloride, and the sodium oxide content in the obtained component B catalyst 1 was less than 0.15% by weight.

[0441] (3) Component A catalyst and component B catalyst 1 were mixed uniformly according to the ratio listed in Table 10 to obtain the start-up catalyst D5 of Example 5. Its properties are shown in Table 12.

[0442] Example 6

[0443] (1) The physical properties of Component A Catalyst 2 are shown in Table 10. It is obtained by subjecting a balance agent from a catalytic cracking unit (different from the FCC balance agent in Example 5) to a cyclone treatment to a certain particle size and then to a chemical demetallization treatment to a certain metal content.

[0444] (2) Component B catalyst:

[0445] Pseudoboehmite and water are mixed uniformly, and concentrated hydrochloric acid having a concentration of 36 wt% is added with stirring, and the acid-aluminum ratio is 0.2 (the molar ratio of HCl to pseudoboehmite calculated as Al2O3); the resulting mixture is aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry; the aged pseudoboehmite slurry has an alumina content of 12 wt%. The modified small-grain Y-type molecular sieve material 2 (properties are shown in Table 11, a product of Sinopec Catalyst Co., Ltd. Qilu Branch), aluminum sol, kaolin and the above-mentioned aged pseudo-boehmite slurry and deionized water were uniformly mixed to form a slurry with a solid content of 30% by weight, and spray-dried to obtain component B catalyst microspheres; the component B catalyst microspheres were calcined at 550°C for 4h; the calcined catalyst microspheres were exchanged at 80°C for 1h according to a weight ratio of component B catalyst microspheres: ammonium salt: H2O = 1:1:10, filtered, and the above-mentioned exchange and filtration process was repeated once, and the catalyst was dried, wherein the ammonium salt was ammonium chloride, and the sodium oxide content of the obtained component B catalyst 2 was less than 0.15% by weight.

[0446] (3) Component A catalyst 2 and component B catalyst 2 were mixed uniformly according to the ratio listed in Table 10 to obtain the start-up catalyst D6 of Example 6. Its properties are shown in Table 12.

[0447] Comparative Example 5

[0448] The start-up catalyst used in Comparative Example 5 only contains the conventional balance agent 5 produced by a catalytic cracking unit, and its physical properties are shown in Table 10.

[0449] Comparative Example 6

[0450] The start-up catalyst used in Comparative Example 6 contained only Component A Catalyst 1 in Example 5, and did not contain Component B Catalyst. The physical properties of Component A Catalyst 1 are shown in Table 10.

[0451] Table 10. Catalyst ratios and properties of Examples and Comparative Examples

[0452] Table 11

[0453] Table 12

[0454] Performance Testing

[0455] The cracking performance of the catalysts of Examples 5 and 6 and Comparative Example 5 was evaluated in an FFB fixed fluidized bed reactor. The evaluation conditions were a reaction temperature of 520°C, a catalyst-oil ratio of 10:1 by weight, and a space velocity of 10 h -1The raw material is intermediate base heavy oil. The physical properties are shown in Table 13. The catalytic performance evaluation results of the start-up catalyst are shown in Table 14.

[0456] Table 13. Crude oil properties

[0457] Table 14. Catalytic performance evaluation results of the start-up catalyst

[0458] The yields mentioned herein are calculated based on the raw material feed.

[0459] Product yield = product yield (weight) / heavy oil feed amount (weight) × 100%

[0460] Coke factor = coke yield (weight) / conversion rate

[0461] Gasoline factor = gasoline yield (weight) / conversion rate

[0462] As shown in Table 14, the startup catalysts provided by the present invention exhibit suitable cracking activity, a low coke factor, and a high gasoline factor. Subsequent startup tests on an industrial catalytic cracking unit demonstrated that the startup catalysts of Examples 5 and 6 efficiently and smoothly enabled the initial startup of the catalytic cracking unit and rapidly optimized product distribution. The catalysts of Comparative Examples 5 and 6, on the other hand, prolonged the unit's stabilization period.

[0463] The following Examples 7 and 8 and Comparative Examples 7 and 8 are used to illustrate the technical effects of the start-up catalyst according to the fourth series of technical solutions of the first aspect above.

[0464] Example 7

[0465] (1) Component A catalyst is the balance agent 7 (or waste agent) from the catalytic cracking unit. The balance agent is subjected to physical cyclone treatment to achieve a certain particle size requirement; it is then subjected to chemical demetallization treatment to achieve a certain metal content. The physical properties are shown in Table 15.

[0466] (2) Component B catalyst:

[0467] Pseudoboehmite and water were mixed uniformly, and concentrated hydrochloric acid with a concentration of 36 wt% was added under stirring, with an acid-to-aluminum ratio of 0.2 (the weight ratio of 36 wt% hydrochloric acid to pseudoboehmite calculated as Al2O3); the resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudoboehmite slurry had an alumina content of 12 wt%; modified small-grain Y-type molecular sieve 1 (average grain size 500 nm, source: Sinopec Catalyst Co., Ltd. Qilu Branch, silicon-aluminum ratio (SiO2 / Al2O3 molar ratio) of 5.2, modified element lanthanum, content of 12 wt%, the same below), ZRP-1 molecular sieve (P2O5 content 6.0 wt%, silicon-aluminum ratio (SiO2 / Al2O3 molar ratio) of 25, Sinopec Catalyst Co., Ltd. Qilu Branch), aluminum sol, silica sol, Kaolin, the aged pseudo-boehmite slurry and deionized water are uniformly mixed to form a slurry with a solid content of 30% by weight, and spray-dried to obtain component B catalyst microspheres; the component B catalyst microspheres are calcined at 550° C. for 4 hours; the calcined component B catalyst microspheres are exchanged at 80° C. for 1 hour according to a weight ratio of component B catalyst: ammonium salt: H2O = 1:1:10, filtered, and the above exchange and filtration processes are repeated once, and then dried, wherein the ammonium salt is ammonium chloride, and the sodium oxide content in the obtained component B catalyst is less than 0.15% by weight.

[0468] (3) Component C catalyst:

[0469] Pseudoboehmite and water were mixed uniformly, and concentrated hydrochloric acid having a concentration of 36% by weight was added with stirring, with an acid-to-aluminum ratio of 0.2 (the weight ratio of 36% by weight concentrated hydrochloric acid to the pseudoboehmite calculated as Al2O3). The resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudoboehmite slurry had an alumina content of 12% by weight. Alumina sol, silica sol, kaolin, the aged pseudoboehmite slurry, and deionized water were uniformly mixed to form a slurry having a solid content of 30% by weight, which was spray-dried and calcined at 550°C for 4 hours.

[0470] Prepare a magnesium nitrate solution by dissolving 18.4 g of magnesium nitrate in 50 g of deionized water. Impregnate the spray-dried microspheres with the magnesium nitrate solution at 50°C for 2 hours, then directly dry and calcine to obtain component C catalyst.

[0471] (4) The catalyst component A, the catalyst component B, and the catalyst component C were mixed uniformly according to the ratio listed in Table 15 to obtain the catalyst D7 of Example 7. The properties of the obtained catalyst D7 are listed in Table 16.

[0472] Example 8

[0473] (1) Component A catalyst is the balance agent 8 from the catalytic cracking unit. The balance agent is treated with physical cyclone to achieve a certain particle size requirement; and then treated with chemical demetallization to achieve a certain metal content. The physical properties are shown in Table 15.

[0474] (2) Component B catalyst:

[0475] Pseudoboehmite and water were uniformly mixed, and concentrated hydrochloric acid having a concentration of 36 wt% was added with stirring, with an acid-to-aluminum ratio of 0.2 (the weight ratio of 36 wt% concentrated hydrochloric acid to the pseudoboehmite calculated as Al2O3). The resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudoboehmite slurry had an alumina content of 12 wt%. Modified small-grain Y-type molecular sieve 1 (average grain size 500 nm, source: Sinopec Catalyst Co., Ltd. Qilu Branch, silicon-aluminum ratio (SiO2 / Al2O3 molar ratio) of 5.2, and modified element lanthanum at a content of 12 wt%) and RMPZ molecular sieve (rare earth content 2.5 wt% calculated as RE2O3, P2O5 content 6.0 wt%, silicon-aluminum ratio (SiO2 / Al2O3 molar ratio) of 25, and a pore distribution with a most probable pore size at 10 nm) were added. )), aluminum sol, silica sol, kaolin and the above-mentioned aged pseudo-boehmite slurry and deionized water are uniformly mixed to form a slurry with a solid content of 30% by weight, and spray dried to obtain a component B catalyst; the component B catalyst microspheres are calcined at 550°C for 4h; the calcined catalyst microspheres are exchanged at 80°C for 1h according to a weight ratio of component B catalyst: ammonium salt: H2O = 1:1:10, filtered, and the above-mentioned exchange and filtration process is repeated once, and the catalyst is dried, wherein the ammonium salt is ammonium chloride, and the sodium oxide content in the obtained component B catalyst is less than 0.15% by weight.

[0476] (3) Component C catalyst:

[0477] Pseudoboehmite and water were uniformly mixed, and concentrated hydrochloric acid having a concentration of 36 wt% was added with stirring, with an acid-to-aluminum ratio of 0.2 (the weight ratio of hydrochloric acid (36 wt%) to pseudoboehmite calculated as Al2O3). The resulting mixture was aged at 70°C for 1.5 hours to obtain an aged pseudoboehmite slurry. The aged pseudoboehmite slurry had an alumina content of 12 wt%. Barium nitrate solution (10.2 g of barium nitrate dissolved in 50 g of deionized water), aluminum sol, silica sol, kaolin, the aged pseudoboehmite slurry, and deionized water were uniformly mixed to form a slurry having a solid content of 30 wt%, which was spray-dried and calcined at 550°C for 4 hours to obtain the component C catalyst.

[0478] (4) The catalyst component A, the catalyst component B, and the catalyst component C were mixed uniformly according to the ratio listed in Table 15 to obtain the catalyst D8 of Example 8. The properties of the obtained catalyst D8 are listed in Table 16.

[0479] Comparative Example 7

[0480] The start-up catalyst used in Comparative Example 7 contains only component A catalyst, that is, the balance agent 9 from the conventional catalytic cracking unit, and its physical properties are shown in Table 15.

[0481] Comparative Example 8

[0482] The start-up catalyst used in Comparative Example 8 contains only the component A catalyst (i.e., balance agent 7) used in Example 7, and does not contain the component B catalyst and the component C catalyst components. The physical properties of the catalyst in Comparative Example 8 are shown in Table 15.

[0483] Table 15. Component parameters of Examples and Comparative Examples

[0484] Table 16. Properties of the start-up catalyst

[0485] In the component B catalyst and the component C catalyst, the content of small-grain Y-type molecular sieve 1 is calculated on a dry basis, the content of ZSM-5 molecular sieve is calculated on a dry basis, the content of pseudo-boehmite is calculated on a dry basis, the content of aluminum sol is calculated on a dry basis, the content of silica sol is calculated on a dry basis, the content of kaolin is calculated on a dry basis, and the content of alkaline earth metal is calculated on a dry basis.

[0486] Performance Testing

[0487] The catalytic cracking start-up catalysts prepared in the examples and comparative examples were tested in a fixed fluidized bed reactor to evaluate their cracking reaction performance. The evaluation conditions were a reaction temperature of 520°C, a catalyst-to-oil ratio of 10, and a space velocity of 10 h. -1 The raw material is hydrogenated heavy oil. The physical properties are shown in Table 17. The evaluation results of the catalytic performance of the start-up catalyst are shown in Table 18.

[0488] Table 17. Properties of Hydrotreated Heavy Oil

[0489] Table 18. Catalytic performance evaluation results of start-up catalysts

[0490] The yields mentioned herein are calculated based on the raw material feed.

[0491] Product yield = product yield (weight) / heavy oil feed amount (weight) × 100%

[0492] Coke factor = coke yield (weight) / conversion rate

[0493] Gasoline factor = gasoline yield (weight) / conversion rate

[0494] Propylene factor = Propylene yield (weight) / Liquefied gas yield

[0495] As shown in Table 18, the startup catalysts provided by the present invention have higher gasoline and propylene factors, achieving the technical goal of increasing gasoline and propylene production. Furthermore, subsequent startup tests on an industrial catalytic cracking unit demonstrated that the startup catalysts of Examples 7 and 8 can efficiently and smoothly start up the catalytic cracking unit during the initial startup phase and rapidly optimize product distribution. In contrast, the use of the catalysts of Comparative Examples 5 and 6 prolonged the unit's stabilization time.

[0496] While exemplary embodiments of the present invention have been described in detail above, the present invention is not limited thereto. Within the technical concept of the present invention, various simple modifications may be made to the technical solution of the present invention, including combining the various technical features in any other suitable manner. These simple modifications and combinations shall also be regarded as disclosed herein and fall within the scope of protection of the present invention.

Claims

1. A composite start-up catalyst, in particular a start-up catalyst for a catalytic cracking unit or a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises 15 to 95% by weight of a component A catalyst selected from a balance agent, and 5 to 85% by weight of a component B catalyst selected from one or more fresh catalysts, preferably a fresh catalytic cracking catalyst or a fresh catalytic cracking catalyst, and an optional component C catalyst; wherein, The balance agent is preferably a catalytic cracking or catalytic cracking balance agent and / or a treated catalytic cracking or catalytic cracking balance agent, wherein the treatment includes a demetallization treatment and / or a particle size adjustment treatment. Preferably, the cracking activity or cracking activity of the catalytic cracking or catalytic cracking balance agent is 55 to 65; the component C catalyst contains 2 to 10 weight percent of a modified metal oxide.

2. The composite start-up catalyst according to claim 1, particularly for a start-up catalyst of a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises: (1) 15 to 95 wt %, preferably 50 to 85 wt % of component A catalyst, and (2) 5 to 85% by weight, preferably 15 to 50% by weight, of a component B catalyst, in, The component A catalyst is a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, wherein the treatment may include a demetallization treatment and / or a particle size adjustment treatment. Preferably, the cracking activity of the component A catalyst is 55 to 65, preferably 57 to 64; The component B catalyst is a fresh catalyst, and its active component includes hollow multi-level porous ZSM-5 nanocrystalline material. The content of the ZSM-5 nanocrystalline material is 5-15% by weight relative to the total weight of the component B catalyst on a dry basis.

3. The composite start-up catalyst according to claim 1, particularly for a start-up catalyst of a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst comprises: (1) 20 to 90% by weight, preferably 75 to 85% by weight, of the catalyst of component A, (2) 5 to 65 wt %, preferably 10 to 20 wt % of component B catalyst, (3) 5 to 15 wt %, preferably 5 to 10 wt % of component C catalyst, in, The component A catalyst is a catalytic cracking balance agent and / or a treated catalytic cracking balance agent, wherein the treatment may include a demetallization treatment and / or a particle size adjustment treatment. Preferably, the cracking activity of the component A catalyst is 55 to 65, preferably 57 to 64; The component B catalyst is a fresh catalyst, and its active component includes ZSM-5 molecular sieve, and the content of the ZSM-5 molecular sieve is 5 to 15 weight % relative to the total weight of the component B catalyst on a dry basis; The component C catalyst contains 2 to 10 weight percent of a modified metal oxide, wherein the modified metal is an alkaline earth metal.

4. The composite start-up catalyst according to claim 1, particularly a start-up catalyst for a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst contains: (1) 15 to 95%, preferably 75 to 95%, of the catalyst of component A, (2) 5 to 85%, preferably 5 to 25%, of component B catalyst, in, The component A catalyst is a catalytic cracking balance agent and / or a treated catalytic cracking balance agent; preferably, the cracking activity of the component A catalyst is 55 to 65, preferably 57 to 64; The component B catalyst is a fresh catalyst, and its active component includes a modified small-grain Y-type molecular sieve material. The content of the modified small-grain Y-type molecular sieve material is 5 to 15% by weight of the component B catalyst on a dry basis.

5. The composite start-up catalyst according to claim 1, particularly a start-up catalyst for a catalytic cracking unit, characterized in that, based on the dry weight of the composite start-up catalyst, the composite start-up catalyst contains: (1) 20 to 90%, preferably 75 to 90%, of component A catalyst, (2) 5 to 65%, preferably 5 to 15%, of component B catalyst, (3) 5 to 15%, preferably 5 to 10%, of component C catalyst, in, The component A catalyst is a catalytic cracking balance agent and / or a treated catalytic cracking balance agent. Preferably, the cracking activity of the component A catalyst is 55-65, preferably 57-64; the component B catalyst is a fresh catalyst, and its main active components include a modified small-grain Y-type molecular sieve and an optional ZSM-5 molecular sieve material. The component C catalyst contains a carrier and a metal oxide, and the component C catalyst contains 2-10 weight % of the metal oxide, and the modified metal is an alkaline earth metal.

6. The composite start-up catalyst according to any one of claims 1 to 3, characterized in that: The specific surface area of ​​the catalyst of component A is ≥100m 2 / g, preferably 100 to 200 m 2 / g; and / or, the component A catalyst has the following particle size distribution: the content of particles with a particle size of 0 to 20 μm is ≤3.0 volume%, preferably ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume%, and the average particle size is 60.0 to 80.0 μm, preferably 65.0 to 80.0 μm; and / or, the component B catalyst has the following particle size distribution: the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume%, The content of particles with a particle size of 0-40 μm is ≤18.0% by volume, the content of particles with a particle size of 0-149 μm is ≥90.0% by volume, and the average particle size is 60.0-85.0 μm; and / or, in the composite start-up catalyst, the content of particles with a particle size of 0-20 μm is ≤2.0% by volume, the content of particles with a particle size of 0-40 μm is ≤18.0% by volume, the content of particles with a particle size of 0-149 μm is ≥90.0% by volume, and the average particle size calculated by volume is 65.0-85.0 μm.

7. The composite start-up catalyst according to any one of claims 1 to 3, characterized in that: The nickel content of the component A catalyst is ≤6000μg / g, preferably 500-6000μg / g; the vanadium content is ≤5000μg / g, preferably ≤3000μg / g, preferably 50-3000μg / g; the rare earth element content is ≤10000μg / g, preferably 500-10000μg / g; the iron content is ≤4500μg / g; and / or, in the composite start-up catalyst, the nickel content is ≤4000μg / g, preferably 200-4000μg / g; the vanadium content is ≤2500μg / g, preferably 300-2500μg / g; and / or, the apparent bulk density of the component B catalyst is 0.8-0.94g / mL, and the wear index is ≤2.

8. The composite start-up catalyst according to claim 4, characterized in that: The specific surface area of ​​the catalyst of component A is ≥100m 2 / g; and / or, the component A catalyst has the following particle size distribution: the content of particles with a particle size of 0 to 20 μm is ≤3.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume%, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume%, and its average particle size is 60.0 to 80.0 μm; and / or, the nickel content of the component A catalyst is ≤6000 μg / g, the vanadium content is ≤4000 μg / g, the iron content is ≤5000 μg / g, and the rare earth element content is ≥10000 μg / g; and / or, the component B catalyst has the following particle size distribution: the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume%, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume% , the content of particles with a particle size of 0 to 149 μm is ≥ 90.0 volume %, and the average particle size is 60.0 to 85.0 μm; and / or, the apparent bulk density of the component B catalyst is 0.80 to 0.94 g / mL, and the attrition index is ≤ 2.0; and / or, the component B catalyst further comprises a carrier, and the content of the carrier is 85 to 95 weight % of the component B catalyst on a dry basis. Preferably, the carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina, and the silica carrier can be one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

9. The composite start-up catalyst according to claim 4, characterized in that: The modified small-grain Y-type molecular sieve material has the following properties: RE2O3 content is 0-18% by weight, Na2O content is not more than 1% by weight, unit cell constant is 2.43-2.47nm, non-framework aluminum content accounts for no more than 30% of the total aluminum content, the ratio of B acid content to L acid content is not less than 2.5, the external surface acid content is 150-300 μmol / g, and the total specific surface area is 580-650m 2 ·g -1 , the average grain size is 0.5-1.0 μm; and / or, the relative crystallinity of the modified small-grain Y-type molecular sieve material is 45-65%, and the lattice collapse temperature is not less than 1030°C.

10. The composite start-up catalyst according to claim 4, characterized in that: The composite start-up catalyst has the following particle size distribution: the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume %, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume %, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume %, and the average particle size is 65.0 to 85.0 μm, and / or, in the composite start-up catalyst, the nickel content is ≤5000 μg / g, the vanadium content is ≤3500 μg / g, the iron content is ≤4500 μg / g, and / or, the coke factor of the composite start-up catalyst is ≤0.140, the gasoline factor is ≥0.420, and / or, the cracking activity of the composite start-up catalyst is 55 to 65; and / or, the apparent bulk density of the composite start-up catalyst is 0.90 to 0.94 g / mL, and the wear index is ≤2.

0.

11. The composite start-up catalyst according to claim 5, characterized in that: The component A catalyst is a catalytic cracking catalyst, and the component A catalyst has the following properties: specific surface area ≥ 100m 2 / g; and / or, nickel content ≤6000μg / g, vanadium content ≤5000μg / g, iron content ≤5000μg / g, sodium content ≤3000μg / g, calcium content ≤3000μg / g; and / or, the component A catalyst has the following particle size distribution: the content of particles with a particle size of 0-20μm is ≤3.0 volume%, the content of particles with a particle size of 0-40μm is ≤18.0 volume%, the content of particles with a particle size of 0-149μm is ≥90.0 volume%, and the average particle size is 60.0-80.0μm; and / or, the cracking activity of the component A catalyst is 55-65; and / or, the crystallinity of the Y-type molecular sieve is ≥20.0%, and the crystallinity of the ZSM-5 molecular sieve is ≥2.0%.

12. The composite start-up catalyst according to claim 5, characterized in that: The apparent bulk density of the component B catalyst is 0.8-0.94 g / mL, and the attrition index is ≤2.0; and / or, the component B catalyst has the following particle size distribution: the content of particles with a particle size of 0-20 μm is ≤2.0 volume%, the content of particles with a particle size of 0-40 μm is ≤18.0 volume%, the content of particles with a particle size of 0-149 μm is ≥90.0 volume%, and the average particle size is 60.0-85.0 μm; and / or, the component B catalyst further includes a matrix carrier and an active component, and the matrix carrier is selected from one or more of natural clay, alumina carrier and silica carrier; and / or, based on the dry weight of the component B catalyst, The content of the matrix carrier on a dry basis is 85 to 95 weight % of the component B catalyst, and the content of the active component on a dry basis is 5 to 15 weight % of the component B catalyst; and / or, the active components of the component B catalyst are a modified small-grain Y-type molecular sieve and an optional ZSM-5 molecular sieve; preferably, the weight ratio of the modified small-grain Y-type molecular sieve to the ZSM-5 molecular sieve is greater than 2; preferably, the average grain size of the modified small-grain Y-type molecular sieve is 300-700nm; the rare earth content of the modified small-grain Y-type molecular sieve can be 1 to 20 weight %; and / or, the silicon-aluminum ratio calculated as a SiO2 / Al2O3 molar ratio is 5.1 to 10.

13. The composite start-up catalyst according to claim 5, characterized in that: The metal oxide loading of the component C catalyst is 2-10 wt %, and / or the metal oxide of the component C catalyst can be one or more of magnesium oxide, barium oxide, strontium oxide and radium oxide.

14. The composite start-up catalyst according to claim 5, characterized in that: The composite start-up catalyst has an apparent bulk density of 0.90 to 0.94 g / mL and an abrasion index of ≤2.0; and / or, the composite start-up catalyst comprises: a nickel content of ≤5000 μg / g, a vanadium content of ≤4000 μg / g, an iron content of ≤4000 μg / g, a sodium content of ≤2000 μg / g, and a calcium content of ≤2000 μg / g; and / or, the composite start-up catalyst has the following particle size distribution: the content of particles with a particle size of 0 to 20 μm is ≤2.0 volume %, the content of particles with a particle size of 0 to 40 μm is ≤18.0 volume %, the content of particles with a particle size of 0 to 149 μm is ≥90.0 volume %, and the average particle size is 65.0 to 85.0 μm; and / or, the cracking activity of the composite start-up catalyst is 55 to 65, the coke factor is ≤0.125, for example, 0.05 to 0.12, the gasoline factor is ≥0.430, for example, 0.43 to 0.48, and the propylene factor is ≥0.420, for example, 0.42 to 0.

47.

15. The composite start-up catalyst according to any one of claims 2 to 3, characterized in that: The ZSM-5 molecular sieve is selected from a hollow multi-level pore ZSM-5 nanocrystalline material, the average grain size of the hollow multi-level pore ZSM-5 nanocrystalline material is 0.2-3.0 μm, the ratio of the bulk silicon-aluminum molar ratio to the surface silicon-aluminum molar ratio of the hollow multi-level pore ZSM-5 nanocrystalline material is 1.0-1.5, and the total specific surface area of ​​the hollow multi-level pore ZSM-5 nanocrystalline material is 340-420 m 2 / g, mesoporous specific surface area is 40-150m 2 / g, the N2 adsorption / desorption curve of the hollow multi-level pore ZSM-5 nanocrystalline material presents an H4 type hysteresis loop, and / or the relative crystallinity of the hollow multi-level pore ZSM-5 nanocrystalline material is 75-95%; and / or, the component B catalyst also includes a carrier, and the content of the carrier is 85-95% by weight of the component B catalyst on a dry basis, and the carrier is selected from one or more of natural clay, alumina carrier and silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol.

16. The composite start-up catalyst according to claim 3, characterized in that: The component C catalyst contains 2 to 10 weight percent of a modified metal oxide and 90 to 98 weight percent of a carrier, wherein the modified metal oxide is an alkaline earth metal oxide; the carrier is selected from one or more of natural clay, an alumina carrier and a silica carrier; preferably, the alumina carrier is one or more of aluminum sol, acidified pseudo-boehmite, hydrated alumina and activated alumina; the silica carrier is one or more of neutral silica sol, acidic silica sol or alkaline silica sol; and / or, the component C catalyst is obtained by modifying inert particles with the modified metal element compound, or by adding the modified metal element compound to an inert particle precursor for slurrying and then spray drying; the modified metal element compound is one or more of magnesium nitrate, barium nitrate, strontium nitrate or radium nitrate.

17. The composite start-up catalyst according to any one of claims 1 to 3, characterized in that: The apparent bulk density of the composite start-up catalyst is 0.90-0.94 g / mL, the wear index of the composite start-up catalyst is ≤2.0; and / or the coke factor of the composite start-up catalyst is ≤0.070, for example, 0.040-0.065; the propylene factor is ≥0.44, for example, 0.44-0.5; and / or the cracking activity is 58-62.

18. A method for preparing the composite start-up catalyst according to any one of claims 1 to 3, characterized in that: The method comprises: preparing the component B catalyst and an optional component C catalyst, and physically mixing the component A catalyst, the component B catalyst and the optional component C catalyst; preferably, the method for preparing the component B catalyst comprises: mixing a matrix carrier, water and a ZSM-5 molecular sieve or a hollow multi-level pore ZSM-5 nanocrystalline material, slurrying, spray drying, and optionally calcining to obtain catalyst particles; mixing the obtained catalyst particles, an ammonium salt and water for ammonium exchange, and optionally washing, so that the Na2O content in the obtained component B catalyst particles is less than 0.15 weight %; preferably, the catalyst particles, the ammonium salt and water are mixed in a weight ratio of 1: (0.1-1): (5-15) for ammonium exchange; and / or, the conditions for the ammonium exchange include: a temperature of 50-100° C. and a time of 0.5-2 hours, preferably, the ammonium salt is selected from ammonium chloride, ammonium sulfate and One or more of ammonium nitrate; and / or, the method for preparing the component C catalyst comprises: mixing a matrix carrier with optional water for slurrying, spray drying to obtain catalyst particles, modifying the modified metal by an impregnation method, drying, and optionally calcining; or, mixing a matrix carrier, a modified metal salt solution and optional water for slurrying, spray drying, and optionally calcining to obtain a third catalyst particle; mixing the obtained catalyst particles, ammonium salt and water for ammonium exchange, and optionally washing, so that the Na2O content in the obtained component C catalyst particles is less than 0.15% by weight; preferably, the catalyst particles, ammonium salt and water are mixed in a weight ratio of 1: (0.1-1): (5-15) for ammonium exchange, wherein the conditions for the ammonium exchange include: a temperature of 50-100°C and a time of 0.5-2 hours, preferably, the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate.

19. The method according to claim 18, characterized in that The component A catalyst is a catalytic cracking balance agent with a cracking activity of 55 to 65, wherein the catalytic cracking balance agent is a balance agent produced by a catalytic cracking device; or, the component A catalyst is a treated balance agent obtained through treatment, wherein the demetallization treatment is a chemical demetallization treatment and / or a physical demetallization treatment, and the particle size adjustment treatment is a gas purge to purge out fine powder therein, or a sieve for screening.

20. A method for preparing the composite start-up catalyst according to any one of claims 1 and 4-5, characterized in that: The method comprises: preparing the component B catalyst and the optional component C catalyst, and physically mixing the component A catalyst, the component B catalyst and the optional component C catalyst uniformly; wherein the preparation method of the component B catalyst comprises: mixing a carrier and / or a carrier precursor / modified small-grain Y-type molecular sieve material and water for slurrying to form a slurry, spray drying, and optionally calcining to obtain catalyst microspheres; ammonium exchange is performed on the obtained catalyst microspheres, and the ammonium exchange makes the Na2O content in the obtained component B catalyst less than 0.15 weight %; preferably, the catalyst microspheres, ammonium salt and water are mixed in a weight ratio of 1: (0.1-1): (5-15) to perform the ammonium exchange, and the conditions of the ammonium exchange include: a temperature of 50-100° C. and a time of 0.5-2 hours, and the ammonium salt is selected from one or more of ammonium chloride, ammonium sulfate and ammonium nitrate; and / or, the preparation method of the component C catalyst comprises: modifying the inert microspheres with metal elements, or adding metal elements to the catalyst precursor, and then spray drying.

21. Use of the composite start-up catalyst according to any one of claims 1 to 17 in the start-up of a newly built catalytic cracking or catalytic cracking unit or in the start-up of a modified catalytic cracking or catalytic cracking unit, preferably, the unit is a MIP catalytic cracking unit or a RTC catalytic cracking unit.

22. A method for starting up a heavy oil or high-density heavy oil catalytic cracking unit, characterized in that: During the start-up phase of the catalytic cracking unit, heavy oil is introduced into the catalytic cracking reactor to contact with the fluidized composite start-up catalyst according to claim 2 for catalytic cracking reaction, or high-density heavy oil is introduced into the catalytic cracking reactor to contact with the fluidized composite start-up catalyst according to claim 3 for catalytic cracking reaction.

23. A method for starting up a heavy oil catalytic cracking unit, characterized in that: During the start-up phase of the catalytic cracking unit, the heavy oil is introduced into the catalytic cracking reactor and brought into contact with the fluidized composite start-up catalyst according to claim 4 or 5 to carry out a catalytic cracking reaction.

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