Preparation method of catalytic cracking catalyst for increasing yield of gasoline and liquefied gas

Abstract

The invention provides a preparation method of a catalytic cracking catalyst for increasing the yield of gasoline and liquefied gas, which comprises the following steps: 1) carrying out pore expansion treatment on kaolin to obtain a first raw material; 2) performing solid-phase ball milling on pseudo-boehmite and zinc salt to obtain a second raw material; and (3) adding a molecular sieve into a mixed system of the first raw material, the second raw material, the viscosity reducer, the binder, the solvent and the acid, and sequentially carrying out mixed pulping, spray drying and roasting treatment to obtain the catalytic cracking catalyst. According to the preparation method provided by the invention, the pore structure of the catalytic cracking catalyst can be improved, and meanwhile, the yield of gasoline and liquefied gas is increased.

Description

Technical Field

[0001] This invention relates to the field of catalytic materials, and more particularly to a method for preparing a catalytic cracking catalyst that produces more light gasoline and liquefied petroleum gas. Background Technology

[0002] Catalytic cracking remains an important method for secondary crude oil processing, and catalysts are the key technology in the entire process. Among the products, low-carbon olefins such as C3 and C4 in gasoline and liquefied petroleum gas (LPG) are still high-value-added products. Therefore, engineers hope to obtain more gasoline and LPG through the catalytic cracking process, which requires the development of catalytic cracking catalysts that can obtain more gasoline and LPG.

[0003] Patent GB2120571A discloses a cracking catalyst composition, wherein the acid-modified kaolin contained in the composition is prepared by: first heating kaolin at 700-910℃ for more than 15 minutes to obtain metakaolin, and then reacting the metakaolin with a mixture selected from hydrochloric acid, nitric acid and their salts to obtain modified kaolin; however, the modified cracking catalyst composition obtained by this process has insufficient cracking activity for heavy oil macromolecules.

[0004] Patent CN106179476A discloses a catalytic cracking catalyst, its preparation method, and its application. The catalytic cracking catalyst contains 1-50% by weight of a mesoporous active material. The mesoporous active material has a pseudo-boehmite crystal phase structure. It has low coke selectivity and high catalytic cracking activity in heavy oil catalytic cracking, and can obtain high diesel yield and low gasoline sulfur content, but the yield of liquefied petroleum gas needs to be improved. Summary of the Invention

[0005] This invention provides a method for preparing a catalytic cracking catalyst that produces more gasoline and liquefied petroleum gas (LPG). This method can improve the pore structure of the catalyst material and increase the yield of gasoline and LPG.

[0006] In detail, the present invention provides a method for preparing a catalytic cracking catalyst that produces more gasoline and liquefied petroleum gas, comprising the following steps:

[0007] 1) Kaolin is subjected to pore-enlarging treatment to obtain the first raw material; the volume of mesopores and macropores in the first raw material is not less than 0.57 cm³. 3 / g;

[0008] 2) The pseudoboehmite and zinc salt were subjected to solid-phase ball milling to obtain the second raw material;

[0009] 3) Molecular sieves are added to a mixture of the first raw material, the second raw material, the viscosity reducer, the binder, the solvent and the acid, and the mixture is sequentially mixed, pulped, spray-dried and calcined to obtain the catalytic cracking catalyst.

[0010] Furthermore, the viscosity reducer is polyacrylamide and / or polyvinyl alcohol.

[0011] Furthermore, the molecular sieve is one or more of HY, REY, USY, REHY, REUSY, and HZSM-5.

[0012] Furthermore, the mass ratio of the first raw material, the second raw material, the thickening agent, and the molecular sieve is 100-300:70-300:20-180:200-300.

[0013] Furthermore, the meso- and macropore volume of the first raw material is 0.57-0.65 cm³. 3 / g.

[0014] Furthermore, the zinc salt is calculated as zinc oxide, and the boehmite is calculated on a dry basis, with a mass ratio of zinc salt to boehmite of 0.075-0.9:1.

[0015] Furthermore, the calcination treatment is carried out at a temperature of 350-600℃ for a time of 0.5-4 hours;

[0016] And / or, the ball milling speed of the solid-phase ball milling treatment is 500-1000 r / min.

[0017] Furthermore, the first raw material is prepared by a method comprising the following processes:

[0018] Kaolin dry basis obtained by one-time calcination of kaolin is mixed with alkaline solution and stirred to obtain kaolin with one-time pore expansion.

[0019] The kaolin, pore-expanding agent, binder, and deionized water that were first expanded were mixed and then subjected to a second calcination process to obtain the first raw material.

[0020] Furthermore, the pore-expanding agent is at least one of glucose, polystyrene microspheres, and polymethyl methacrylate microspheres.

[0021] Furthermore, the mass ratio of the pore-expanding agent to the kaolin used for primary pore expansion is 0.015-0.06:1.

[0022] Furthermore, the temperature of the first calcination treatment is 940-1000℃, and the time is 1-3 hours;

[0023] And / or, the secondary calcination treatment is carried out at a temperature of 400-600℃ for 1-3 hours.

[0024] In the preparation method provided by the present invention, kaolin is first expanded to form a first raw material with more medium and large pore structures. Then, kaolin and a specific second raw material are added to the catalyst system together, which can synergistically improve the yield and selectivity of gasoline and liquefied gas. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below. The specific embodiments listed below are merely descriptions of the principles and features of the present invention, and the examples are only for explaining the present invention and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In this application, the term "and / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone. A and B can be singular or plural. The character " / " generally indicates that the related objects before and after are in an "or" relationship.

[0027] In this application, the term "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0028] In this application, the term "micropores" refers to pores with a diameter < 2 nm; the term "mesopores" refers to pores with a diameter in the range of 2-50 nm; the term "macropores" refers to pores with a diameter > 50 nm; and the term "meso-macropore material" refers to a material that includes both mesopores and macropores.

[0029] In detail, the present invention provides a method for preparing a catalytic cracking catalyst that produces more gasoline and liquefied petroleum gas, comprising the following steps:

[0030] 1) Kaolin is subjected to pore-enlarging treatment to obtain the first raw material; the volume of mesopores and macropores in the first raw material is not less than 0.57 cm³. 3 / g;

[0031] 2) The pseudoboehmite and zinc salt were subjected to solid-phase ball milling to obtain the second raw material;

[0032] 3) Molecular sieves are added to a mixture of the first raw material, the second raw material, the viscosity reducer, the binder, the solvent and the acid, and the mixture is sequentially mixed, pulped, spray-dried and calcined to obtain the catalytic cracking catalyst.

[0033] In the preparation method of the present invention, kaolin is first subjected to pore-expanding treatment to form a first raw material with more medium and large pore structures. Then, boehmite and zinc salt are subjected to solid-phase ball milling to form a second raw material. The second raw material can increase the alumina content in the catalytic cracking catalyst material and reduce the catalyst surface coverage caused by heavy metal pollution. The first and second raw materials are added together to the catalyst system to synergistically improve the selectivity of gasoline and liquefied gas.

[0034] The present invention does not specifically limit the zinc salts described above. Those skilled in the art may use conventional inorganic zinc salts, such as, but not limited to, one or more mixtures selected from zinc chloride, zinc nitrate, and zinc sulfate.

[0035] It is understandable that binders are an essential part of the catalyst forming process, playing an important role in helping the catalyst to form and enhancing its strength. The aforementioned binders include, but are not limited to, one or more of the following: boehmite, silica, SB powder, diatomaceous earth, aluminum hydroxide, aluminum sol, silica-alumina, and alumina.

[0036] It is understood that the purpose of adding acid is mainly to react with the binder and improve the bonding effect. Therefore, any acidic substance that can decompose under calcination conditions and provide a sufficient concentration of hydrogen ions is acceptable. Preferably, it is an acidic substance that can completely decompose into oxide gas at 350°C, such as one or more of organic matter, inorganic matter, and salts, and more specifically, nitric acid, citric acid, acetic acid, ammonium nitrate, etc. For example, the acidic substance accounts for 2-4% of the dry basis mass of the binder. The purpose of adding a viscosity reducer is to make the raw materials more evenly dispersed.

[0037] In one specific embodiment, after adding molecular sieves to the mixed system, the pH value of the system is 3-5.

[0038] In one specific embodiment, the ball milling speed for the solid-phase ball milling process is 500-1000 r / min. The ball milling speed can affect the formation of the second raw material to some extent. If the ball milling speed is below 500 r / min, the reaction between boehmite and zinc salt is insufficient; if the ball milling speed is above 1000 r / min, energy consumption is high, and other side reactions may occur.

[0039] The present invention does not specifically limit the ball milling apparatus described above. In one specific embodiment, Unionprocess Corporation Qingdao Lianrui Precision Machinery Co., Ltd. is used.

[0040] For example, the solid-phase ball milling treatment time can be 20-60 minutes.

[0041] In one specific embodiment, the anti-tack agent is polyacrylamide and / or polyvinyl alcohol.

[0042] In one specific embodiment, the molecular sieve is one or more of HY, REY, USY, REHY, REUSY, and HZSM-5.

[0043] In one specific embodiment, the mass ratio of the first raw material, the second raw material, the thickening agent, and the molecular sieve is 100-300:70-300:20-180:200-300.

[0044] In one specific embodiment, the zinc salt is calculated as zinc oxide, and the boehmite is calculated on a dry basis, with a mass ratio of zinc salt to boehmite of 0.075-0.9:1. This ratio of zinc salt and boehmite can form a composite material with superior iron resistance, which is beneficial for improving the selectivity of gasoline and liquefied petroleum gas.

[0045] In one specific embodiment, the meso- and macro-pore volume of the first raw material is 0.57-0.65 cm³. 3 / g.

[0046] In one specific embodiment, the calcination treatment is carried out at a temperature of 350-600°C for a time of 0.5-4 hours.

[0047] In one specific embodiment, the first raw material is prepared by a method comprising the following processes:

[0048] Kaolin dry basis obtained by one-time calcination of kaolin is mixed with alkaline solution and stirred to obtain kaolin with one-time pore expansion.

[0049] The kaolin, pore-expanding agent, binder, and deionized water that were first expanded were mixed and then subjected to a second calcination process to obtain the first raw material.

[0050] The present invention does not specifically limit the temperature and time of the above-mentioned alkali treatment. Technicians can adjust them according to the actual situation. In order to save time and ensure the stability of the material pore structure, in a preferred embodiment, the alkali treatment temperature is 90-95°C and the treatment time is 1-3 hours.

[0051] In one specific embodiment, the dry basis of the kaolin reacts with the OH in the alkaline solution. -The mass ratio is 3-11:1. The amount of alkali used in the alkali treatment affects the pore structure of kaolin. If the amount of alkali is too small, the pore expansion may be insufficient. However, as the amount of alkali increases to a certain extent, the pore expansion of kaolin reaches its limit, and the amount of alkali no longer significantly affects the pore structure. The amount of alkali used within the range of the above-described embodiments of this invention can achieve a better pore expansion effect.

[0052] It is understandable that the binder is an essential part of the first raw material forming process, playing a role in helping the first raw material to form. However, it can also have an adverse effect on the pores of the kaolin clay after the first pore expansion. Therefore, adding a pore expander to expand the pores again can improve the above problems. For example, the binder includes, but is not limited to, one or more of boehmite, silica, SB powder, diatomaceous earth, aluminum hydroxide, aluminum sol, silica-alumina, and alumina.

[0053] In one specific embodiment, the pore-expanding agent is at least one of glucose, polystyrene microspheres, and polymethyl methacrylate microspheres.

[0054] Furthermore, the polystyrene microspheres or polymethyl methacrylate microspheres have a particle size of 50-100 nm.

[0055] For example, the polystyrene microspheres or polymethyl methacrylate microspheres have a weight-average molecular weight of 6,000-20,000 g / mol.

[0056] In one specific embodiment, the mass ratio of the pore-expanding agent to the kaolin used for primary pore expansion is 0.015-0.06:1. If the mass ratio of the pore-expanding agent to the kaolin used for primary pore expansion is too small, the pore structure of the kaolin material will not be effectively improved; if the mass ratio is too large, it may affect the strength of the catalytic material.

[0057] In one specific embodiment, the temperature of the first calcination treatment is 940-1000℃, and the time is 1-3 hours;

[0058] And / or, the secondary calcination treatment is carried out at a temperature of 400-600℃ for 1-3 hours.

[0059] The present invention will be further described below with reference to specific embodiments:

[0060] The present invention is further illustrated below with reference to specific embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions in the art or as recommended by the manufacturer; the raw materials and reagents used, unless otherwise specified, are all commercially available from the conventional market. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention are within the scope of protection claimed by the present invention.

[0061] The pore volumes of mesopores and macropores mentioned below were determined by mercury porosimetry (for analytical methods, please refer to "Modern Catalysis Research Methods", edited by Xin Qin et al., Science Press, 2009).

[0062] Raw material sources: Zinc chloride, zinc nitrate, zinc sulfate, and hydrochloric acid (concentration 36%), all analytical grade, produced by Sinopharm Group; kaolin, alkaline solution (NaOH content approximately 14 wt%), boehmite, alumina sol (Al2O3 content approximately 19.4 wt%), polystyrene microspheres, and polymethyl methacrylate microspheres, produced by Lanzhou Petrochemical Company; HY, REY, USY, REHY, REUSY, and HZSM-5 are produced by Lanzhou Petrochemical Company.

[0063] The ball milling used in the following experiments was performed using a ball mill from Unionprocess Qingdao Lianrui Precision Machinery Co., Ltd.

[0064] Example 1

[0065] This example provides a method for preparing a catalytic cracking catalyst that produces both gasoline and liquefied petroleum gas, comprising the following steps:

[0066] 1) Kaolin was calcined at 960℃ for 2.2 hours, and then 1260g of dry calcined kaolin and 2824g of alkaline solution were treated at 96℃ for 1.5 hours. After filtration, washing and drying, modified kaolin was obtained.

[0067] 2) The above-mentioned modified kaolin 350g, polystyrene microspheres 7g (particle size 50nm, weight average molecular weight 9000g / mol), aluminum sol 96g and deionized water are mixed and pulped, and then subjected to a first calcination treatment at 460℃ for 2 hours to obtain the first raw material C1;

[0068] 3) Mix 175g of boehmite dry basis and 226g of zinc chloride evenly, and then mechanically ball-mill for 20 minutes at a ball mill speed of 600r / min to obtain the second raw material;

[0069] 4) Mix 270g of the first raw material C1, 175g of the second raw material, 180g of the viscosity reducer polyacrylamide, 260g of pseudoboehmite, 3580g of deionized water, and 185g of hydrochloric acid evenly. Then add 250g of USY molecular sieve and 125g of HZSM-5 molecular sieve and mix and slurry evenly. The pH value is 3. Spray dry and calcine at 400℃ for 1 hour to obtain the iron-resistant catalytic cracking catalyst F1.

[0070] Example 2

[0071] This example provides a method for preparing a catalytic cracking catalyst that produces both gasoline and liquefied petroleum gas, comprising the following steps:

[0072] 1) Kaolin was calcined at 990℃ for 2.5 hours, and then 331g of dry calcined kaolin and 1112g of alkali solution were treated at 95℃ for 4 hours. After filtration, washing and drying, modified kaolin was obtained.

[0073] 2) The above-mentioned modified kaolin 696g, polymethyl methacrylate microspheres 35g (particle size 80nm, weight average molecular weight 20000g / mol), aluminum sol 323g and deionized water are mixed and pulped, and then subjected to a first calcination treatment at 460℃ for 2 hours to obtain the first raw material C2.

[0074] 3) Mix 892g of boehmite (dry basis) and 886g of zinc sulfate evenly, and then mechanically ball-mill for 15 minutes at a speed of 800r / min to obtain the second raw material;

[0075] 4) Mix 108g of the first raw material C2, 283g of the second raw material, 20g of the viscosity reducer polyvinyl alcohol, 215g of pseudoboehmite, 980g of deionized water, and 37g of hydrochloric acid evenly. Then add 130g of HY molecular sieve and 120g of REY molecular sieve and mix and slurry evenly. The pH value is 5. Spray dry and calcine at 600℃ for 0.5 hours to obtain the iron-resistant catalytic cracking catalyst F2.

[0076] Example 3

[0077] This example provides a method for preparing a catalytic cracking catalyst that produces both gasoline and liquefied petroleum gas. The preparation method includes the following steps:

[0078] 1) Kaolin was calcined at 980℃ for 1.2 hours, and then 786g of dry calcined kaolin and 1321g of alkali solution were treated at 94℃ for 5 hours. After filtration, washing and drying, modified kaolin was obtained.

[0079] 2) The above-mentioned modified kaolin 732g, polystyrene microspheres 29g (particle size 100nm, weight average molecular weight 6000g / mol), aluminum sol 264g and deionized water are mixed and pulped, and then subjected to a first calcination treatment at 520℃ for 3 hours to obtain the first raw material C3.

[0080] 3) Mix 354g of boehmite dry basis, 69g of zinc chloride, and 84g of zinc sulfate evenly, and then mechanically ball-mill for 25 minutes at a speed of 1000r / min to obtain the second raw material;

[0081] 4) Mix 232g of the first raw material C3, 73g of the second raw material, 15g of the viscosity reducer polyvinyl alcohol, 10g of polyacrylamide, 315g of boehmite, 1535g of deionized water, and 56g of hydrochloric acid evenly. Then add 280g of REUSY molecular sieve and mix evenly. The pH value is 4. Spray dry and calcine at 500℃ for 2 hours to obtain iron-resistant catalytic cracking catalyst F3.

[0082] Example 4

[0083] This example provides a method for preparing a catalytic cracking catalyst that produces both gasoline and liquefied petroleum gas. The preparation method includes the following steps:

[0084] 1) Kaolin was calcined at 940℃ for 3 hours, and then 1260g of dry calcined kaolin and 2824g of alkaline solution were treated at 96℃ for 1.5 hours. After filtration, washing and drying, modified kaolin was obtained.

[0085] 2) The above-mentioned modified kaolin 350g, polystyrene microspheres 7g (particle size 50nm, weight average molecular weight 9000g / mol), aluminum sol 96g and deionized water are mixed and pulped, and then subjected to a first calcination treatment at 600℃ for 1.5 hours to obtain the first raw material C4.

[0086] 3) Mix 175g of boehmite dry basis and 226g of zinc chloride evenly, and then mechanically ball-mill for 20 minutes at a ball mill speed of 600r / min to obtain the second raw material;

[0087] 4) Mix 270g of the first raw material C1, 175g of the second raw material, 180g of the viscosity reducer polyacrylamide, 260g of pseudoboehmite, 3580g of deionized water, and 185g of hydrochloric acid evenly. Then add 250g of USY molecular sieve and 125g of HZSM-5 molecular sieve and mix evenly. The pH value is 3.1. Spray dry and calcine at 400℃ for 1 hour to obtain the iron-resistant catalytic cracking catalyst F4.

[0088] Example 5

[0089] The preparation method of the catalytic cracking catalyst provided in this example is basically the same as that in Example 1, except that the particle size of the polystyrene microspheres is 20 nm, and the first raw material C5 and catalyst F5 are finally obtained.

[0090] Example 6

[0091] The preparation method of the catalytic cracking catalyst provided in this example is basically the same as that in Example 1, except that the second raw material in step 4) is changed to 15g, and finally the first raw material C6 and catalyst F6 are obtained.

[0092] Example 7

[0093] The preparation method of the catalytic cracking catalyst provided in this example is basically the same as that in Example 1, except that the polystyrene microspheres in step 3) are changed to 67g, and finally the first raw material C7 and catalyst F7 are obtained.

[0094] Example 8

[0095] The preparation method of the catalytic cracking catalyst provided in this example is basically the same as that in Example 1, except that the polystyrene microspheres are replaced with glucose, and the first raw material C8 and the catalyst F8 are finally obtained.

[0096] Comparative Example 1

[0097] This example provides a method for preparing a catalytic cracking catalyst, including the following steps:

[0098] 1) Kaolin was calcined at 960℃ for 2.2 hours, and then 1260g of dry calcined kaolin and 2824g of alkaline solution were treated at 96℃ for 1.5 hours. After filtration, washing and drying, modified kaolin was obtained.

[0099] 2) Mix 350g of the modified kaolin, 7g of polystyrene microspheres (particle size 50nm, weight average molecular weight 9000g / mol), 96g of aluminum sol and deionized water, and calcine at 460℃ for 2 hours to obtain the first raw material D1.

[0100] 3) Mix 270g of the first raw material D1 with 180g of the viscosity reducer polyacrylamide, 99g of zinc chloride, 336g of boehmite, 3580g of deionized water and 185g of hydrochloric acid evenly. Then add 250g of USY molecular sieve and 125g of HZSM-5 molecular sieve and mix evenly. The pH value is 3. Spray dry and calcine at 400℃ for 1 hour to obtain the iron-resistant catalytic cracking catalyst S1.

[0101] Comparative Example 2

[0102] This example provides a method for preparing a catalytic cracking catalyst, including the following steps:

[0103] 1) Mix 892g of boehmite (dry basis) and 886g of zinc sulfate evenly, and then mechanically ball-mill for 15 minutes at a speed of 800r / min to obtain the second raw material;

[0104] 2) Mix 696g of dry kaolin, 35g of polymethyl methacrylate microspheres (particle size 80nm, weight average molecular weight 20000g / mol), 323g of aluminum sol and deionized water, and calcine at 460℃ for 2 hours to obtain the first raw material D2.

[0105] 3) Mix 108g of the first raw material D2, 283g of the second raw material, 20g of the viscosity reducer polyvinyl alcohol, 215g of pseudoboehmite, 980g of deionized water, and 37g of hydrochloric acid evenly. Then add 130g of HY molecular sieve and 120g of REY molecular sieve and mix and slurry evenly. The pH value is 5. Spray dry and calcine at 600℃ for 0.5 hours to obtain the iron-resistant catalytic cracking catalyst S2.

[0106] Comparative Example 3

[0107] This example provides a method for preparing a catalytic cracking catalyst, including the following steps:

[0108] 1) Kaolin was calcined at 980℃ for 1.2 hours, and then 786g of dry calcined kaolin and 1321g of alkali solution were treated at 94℃ for 5 hours. After filtration, washing and drying, modified kaolin was obtained.

[0109] 2) Mix 354g of boehmite (dry basis), 69g of zinc chloride, and 84g of zinc sulfate evenly, and then mechanically ball-mill for 25 minutes at a speed of 1000r / min to obtain the second raw material;

[0110] 3) Mix 732g of the modified kaolin, 264g of aluminum sol and deionized water, pulverize, and calcine at 520℃ for 3 hours to obtain the first raw material D3;

[0111] 4) Mix 232g of the first raw material D3, 73g of the second raw material, 15g of the viscosity reducer polyvinyl alcohol, 10g of polyacrylamide, 315g of pseudoboehmite, 1535g of deionized water, and 56g of hydrochloric acid evenly. Then add 280g of REUSY molecular sieve and mix and slurry evenly. The pH value is 4. Spray dry and calcine at 500℃ for 2 hours to obtain the iron-resistant catalytic cracking catalyst S3.

[0112] Table 1. Results of characterization of the first feed pore volume.

[0113]

[0114] Test case

[0115] The catalytic activity of the catalytic cracking catalyst was tested: the selectivity of the catalyst for cracking reaction was evaluated in a small fixed fluidized bed (FFB) test unit (XGL-2, Luoyang). Before hydrothermal treatment, the catalyst was iron-contaminated to an iron concentration of 8000 μg / g. The iron-contaminated catalyst was then hydrothermally treated at 800℃ and 100% steam for 4 hours. The hydrothermally treated catalyst was then subjected to reaction selectivity evaluation in a fixed-bed fluidized bed test unit. The feedstock was Lanzhou Petrochemical catalytic feedstock, with specific properties shown in Table 2. The reaction temperature was 500-535℃, and the space velocity was 12-15 h⁻¹. -1 With an oil-to-agent ratio of 5, F1-F8 and S1-S3 were evaluated on a fixed fluidized bed device, and the results are listed in Table 3.

[0116] Table 2 Raw Material Properties

[0117]

[0118] Table 3 Evaluation results of catalyst-fixed fluidized bed devices

[0119]

[0120]

[0121] Note: "Light yield" in the table refers to the sum of the yields of diesel and C5 gasoline.

[0122] As can be seen from the data in Table 3, compared with the comparative example, the catalytic cracking catalyst prepared in the example showed a higher conversion rate through performance evaluation, and its yield of liquefied gas and gasoline was significantly higher.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a catalytic cracking catalyst that produces both gasoline and liquefied petroleum gas, characterized in that, Includes the following steps: 1) Kaolin is subjected to pore-enlarging treatment to obtain the first raw material; wherein, the volume of mesopores and macropores in the first raw material is not less than 0.57 cm³. 3 / g; 2) The pseudoboehmite and zinc salt were subjected to solid-phase ball milling to obtain the second raw material; 3) Molecular sieves are added to a mixture of the first raw material, the second raw material, the viscosity reducer, the binder, the solvent and the acid, and the mixture is sequentially mixed, pulped, spray-dried and calcined to obtain the catalytic cracking catalyst.

2. The preparation method according to claim 1, characterized in that, The viscosity reducer is polyacrylamide and / or polyvinyl alcohol.

3. The preparation method according to claim 1, characterized in that, The molecular sieve is one or more of HY, REY, USY, REHY, REUSY, and HZSM-5.

4. The preparation method according to any one of claims 1-3, characterized in that, The mass ratio of the first raw material, the second raw material, the thickening agent, and the molecular sieve is 100-300:70-300:20-180:20-300.

5. The preparation method according to any one of claims 1-3, characterized in that, The meso- and macropore volumes of the first raw material are 0.57-0.65 cm³. 3 / g.

6. The preparation method according to any one of claims 1-3, characterized in that, The zinc salt is calculated as zinc oxide, and the pseudoboehmite is calculated on a dry basis. The mass ratio of zinc salt to pseudoboehmite is 0.075-0.9:

1.

7. The preparation method according to any one of claims 1-3, characterized in that, The calcination treatment is carried out at a temperature of 350-600℃ for a time of 0.5-4 hours. And / or, the ball milling speed of the solid-phase ball milling treatment is 500-1000 r / min.

8. The preparation method according to any one of claims 1-3, characterized in that, The first raw material is prepared by a method comprising the following processes: Kaolin dry basis obtained by one-time calcination of kaolin is mixed with alkaline solution and stirred to obtain kaolin with one-time pore expansion. The kaolin, pore-expanding agent, binder, and deionized water that were first expanded were mixed and then subjected to a second calcination process to obtain the first raw material.

9. The preparation method according to claim 8, characterized in that, The pore-expanding agent is at least one of glucose, polystyrene microspheres, and polymethyl methacrylate microspheres; And / or, the mass ratio of the pore-expanding agent to the kaolin used for primary pore expansion is 0.015-0.06:

1.

10. The preparation method according to claim 8, characterized in that, The temperature of the first calcination treatment is 940-1000℃, and the time is 1-3 hours; And / or, the secondary calcination treatment is carried out at a temperature of 400-600℃ for 1-3 hours.

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