Molecular sieve composite material, preparation method and application thereof

Abstract

The application provides a molecular sieve composite material and a preparation method and application thereof. The preparation method comprises the following steps: mixing La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, a Y molecular sieve directing agent, an organic matter, an aluminum source, an alkali source, a silicon source and water to obtain a mixture A, and performing crystallization on the mixture A to obtain a solid phase Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material through solid-liquid separation; wherein the organic matter comprises at least one of hydroxypropyl methyl cellulose, polyethylene glycol and cetyltrimethylammonium bromide. The Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide is a micropore-mesopore composite material, has a high mesopore pore size distribution, has a high infrared acid amount, has high aromatic hydrocarbon inferior distillate selective cracking performance, and can realize high light naphtha and heavy naphtha yield in hydrocracking.

Description

Technical Field

[0001] This invention belongs to the field of molecular sieve material preparation technology, specifically relating to molecular sieve composite materials suitable for hydrocracking to prepare light naphtha and heavy naphtha, their preparation methods and applications. Background Technology

[0002] Molecular sieves, due to their unique pore structure, are widely used in adsorption, separation, and catalysis, especially in the petrochemical industry. With the continuous expansion of molecular sieve catalytic applications, single-channel molecular sieves can no longer meet the diverse needs of catalyst preparation. Microporous molecular sieves excel in heterogeneous catalysis applications primarily due to their strong acidity and high structural stability. However, because microporous molecular sieves generally have small pore sizes and long, narrow channels, it is difficult for large molecules in reactants, such as heavy oil, to diffuse into the pores. This reduces the utilization rate of acidic sites within the microporous molecular sieve channels. Simultaneously, the narrow, long channels result in significant diffusion resistance, hindering the rapid diffusion and overflow of reaction product molecules, potentially leading to deep cracking and coking. While mesoporous molecular sieves can compensate for the diffusion limitations of microporous molecular sieves within reactants and products, their structural stability is often poor, further limiting their catalytic applications. Microporous-mesoporous composite molecular sieve materials can produce good synergistic effects and catalytic performance by combining the strengths and weaknesses of several individual materials, making their overall performance superior to that of the original constituent materials. This type of molecular sieve with multiple structures and superimposed functions can avoid the defects of single pore structures. The multi-level pore system can provide pores of different sizes at the same time, which will be of great help in solving problems such as mass transfer of macromolecules.

[0003] CN111484037A discloses a method for synthesizing SSZ-13 molecular sieves with different silica-to-alumina ratios via Y-type molecular sieve crystallization. The method uses TMADaOH as a structure-directing agent, mixing an alkali source, a silicon source, the structure-directing agent, a mesoporous template agent, and water uniformly. Different amounts of aluminum source are added to prepare a sol, and then Y-type molecular sieves are added to obtain an initial gel. A hydrothermal crystallization reaction is then carried out, and the crystallization product is obtained after the reaction is complete. The product is cooled, washed to neutral, and dried to obtain molecular sieve powder. The molecular sieve powder is then calcined to obtain SSZ-13 molecular sieves with different silica-to-alumina ratios. However, the SSZ-13 molecular sieves obtained by this method have relatively low pore size and pore volume, poor selective cracking performance for aromatic low-grade distillate oils, and low yields of light and heavy naphtha produced by hydrocracking. Therefore, this method is not suitable for the hydrocracking production of light and heavy naphtha.

[0004] CN110357121A discloses a method for preparing small-crystal nano-hierarchical porous SSZ-13 molecular sieve. The method uses TMADaOH as a structure-directing agent and TPOAC as a mesoporous template agent. An alkali source, silicon source, structure-directing agent, and mesoporous template agent are mixed uniformly with water. An aluminum source is added or not to prepare a sol, and a Y-type molecular sieve is added to obtain an initial gel. A hydrothermal crystallization reaction is then carried out, and the reaction product is calcined to obtain the small-crystal nano-hierarchical porous SSZ-13 molecular sieve. However, the SSZ-13 molecular sieve synthesized by this method exhibits poor selective cracking performance for aromatic low-grade distillate oils, and the yield of light naphtha and heavy naphtha produced by hydrocracking is low, making it unsuitable for the hydrocracking production of light naphtha and heavy naphtha.

[0005] CN114130427A discloses a Y / SSZ-13 / rare earth / ASA composite material, which is prepared by mixing Y molecular sieve, SSZ-13 molecular sieve, aluminum source, alkaline compound, water, silicon source and rare earth. However, this Y / SSZ-13 / rare earth / ASA composite material has poor selective cracking performance for aromatic low-quality distillate oils, and the yield of light naphtha and heavy naphtha produced by hydrocracking is low, making it unsuitable for the hydrocracking production of light naphtha and heavy naphtha.

[0006] CN106311319A discloses a hydrocracking catalyst containing a micro-mesoporous composite molecular sieve, which is a micro-mesoporous Beta / KIT-6 composite molecular sieve. This composite molecular sieve has low acid strength, poor selective cracking performance for low-grade aromatic distillate oils, and low yields of light and heavy naphtha produced by hydrocracking, making it unsuitable for the production of light and heavy naphtha by hydrocracking.

[0007] In short, existing molecular sieves generally suffer from poor selective cracking performance of aromatic inferior distillate oils and low yields of light and heavy naphtha produced by hydrocracking. Therefore, there is still a need to research molecular sieve materials with high selective cracking performance of aromatic inferior distillate oils and the ability to achieve high yields of light and heavy naphtha from hydrocracking. Summary of the Invention

[0008] The purpose of this invention is to provide a molecular sieve material with selective cracking performance for low-grade aromatic distillate oils and capable of achieving high yields of light naphtha and heavy naphtha through hydrocracking, as well as a method for preparing the molecular sieve material and its applications.

[0009] To achieve the above objectives, the present invention provides the following three technical solutions.

[0010] In a first aspect, the present invention provides a method for preparing a molecular sieve composite material, wherein the method includes:

[0011] KIT-6 molecular sieve was spray-adsorbed with a lanthanum salt-containing phosphomolybdic acid complex aqueous solution, and then dried and calcined to obtain La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide.

[0012] According to the mass ratio of (0.8-1.5) La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide: (0.08-1.5) Y molecular sieve directing agent: 1 Al2O3: (0.08-1.0) Na2O: (2.3-3.3) SiO2: (0.3-0.7) organic matter: (13-41) H2O, La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, Y molecular sieve directing agent, organic matter, aluminum source, alkali source, silicon source and water Y molecular sieve directing agent are added. Mixture A is obtained by mixing an agent, La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, organic matter, aluminum source, alkali source, silicon source and water. Mixture A is crystallized to obtain a slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide. The Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide slurry is subjected to solid-liquid separation to obtain a solid Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material, which is the molecular sieve composite material.

[0013] The organic compound includes at least one of hydroxypropyl methylcellulose, polyethylene glycol, and hexadecyltrimethylammonium bromide.

[0014] The technical solution provided by this invention involves mixing La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, Y molecular sieve directing agent, organic matter (hydroxypropyl methylcellulose, polyethylene glycol and hexadecyltrimethylammonium bromide) with a silicon-aluminum base source and then crystallizing the mixture to obtain a Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material with selective cracking performance for high aromatic low-quality distillate oils and capable of achieving high yields of light naphtha and heavy naphtha through hydrocracking.

[0015] According to a preferred embodiment of the first aspect, the polyethylene glycol includes at least one of PEG2000 and PEG200.

[0016] According to a preferred embodiment of the first aspect, the lanthanum salt is selected from lanthanum nitrate.

[0017] According to a preferred embodiment of the first aspect, the aluminum source used to prepare mixture A includes at least one of aluminum sulfate and sodium aluminate.

[0018] According to a preferred embodiment of the first aspect, the alkali source used to prepare mixture A includes at least one of sodium aluminate and potassium hydroxide.

[0019] According to a preferred embodiment of the first aspect, the silicon source used to prepare mixture A includes at least one of water glass and silica sol.

[0020] According to a preferred embodiment of the first aspect, the Y-molecule sieve directing agent is prepared by the following method:

[0021] The alkali source, aluminum source, silicon source and water were mixed according to the molar ratio of (6-9)Na2O:1Al2O3:(7-13)SiO2:(200-350)H2O, and then aged to obtain Y molecular sieve directing agent;

[0022] Furthermore, the aging temperature is 20-60°C; even further, the aging temperature is 25-40°C;

[0023] Furthermore, the aging time is 10-24 hours; even further, the aging time is 12-24 hours.

[0024] Furthermore, the aluminum source used in the preparation of the Y molecular sieve directing agent includes at least one of aluminum sulfate and sodium aluminate;

[0025] Furthermore, the alkaline source used in the preparation of the Y molecular sieve directing agent includes at least one of sodium aluminate and potassium hydroxide;

[0026] Furthermore, the silicon source used in preparing the Y molecular sieve directing agent includes at least one of water glass and silica sol;

[0027] Further, the alkali source, aluminum source, silicon source and water are mixed according to the molar ratio of (6.5-7.5)Na2O:1Al2O3:(9-11)SiO2:(220-300)H2O, and then aged to obtain Y molecular sieve directing agent;

[0028] Further, sodium aluminate solution A, water glass solution A, and water are mixed and aged to obtain Y molecular sieve directing agent; wherein, based on the total mass of sodium aluminate solution A as 100%, the content of Al2O3 in sodium aluminate solution A is 4-8 wt% and the content of Na2O is 20-30 wt%; based on the total mass of water glass solution A as 100%, the content of SiO2 in water glass solution A is 20-40 wt%; even further, based on the total mass of sodium aluminate solution A as 100%, the content of Al2O3 in sodium aluminate solution A is 5-7 wt% and the content of Na2O is 25-30 wt%; based on the total mass of water glass solution A as 100%, the content of SiO2 in water glass solution A is 25-30 wt%.

[0029] According to the preferred embodiment of the first aspect, in the process of preparing La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, the mass ratio of KIT-6 molecular sieve to lanthanum nitrate to phosphomolybdenum heteropolyacid to water is 1:(0.01-0.12):(0.1-0.25):(0.5-2).

[0030] Furthermore, the mass ratio of KIT-6 molecular sieve to lanthanum nitrate to phosphomolybdic heteropolyacid to water is 1:(0.05-0.1):(0.15-0.2):(0.5-2).

[0031] According to a preferred embodiment of the first aspect, the drying temperature during the preparation of the La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide is 80-100°C.

[0032] According to the preferred embodiment of the first aspect, the calcination temperature during the preparation of the La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide is 300-400℃.

[0033] According to a preferred embodiment of the first aspect, the calcination atmosphere during the preparation of the La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide is an air atmosphere.

[0034] According to a preferred embodiment of the first aspect, the crystallization temperature is 90-100°C; further, the crystallization temperature is 95-100°C.

[0035] According to a preferred embodiment of the first aspect, the crystallization time is 24-48 hours.

[0036] According to a preferred embodiment of the first aspect, mixture A is obtained by mixing La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, Y molecular sieve directing agent, organic matter, aluminum source, alkali source, silicon source and water.

[0037] Mixture A is obtained by mixing La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, Y molecular sieve directing agent, organic matter, aluminum sulfate solution, sodium aluminate solution B, water glass solution B and water.

[0038] Specifically, based on the total mass of the sodium aluminate solution B as 100%, the sodium aluminate solution B contains 5-15 wt% Al2O3 and 5-20 wt% Na2O; based on the total mass of the water glass solution B as 100%, the water glass solution A contains 20-40 wt% SiO2; and based on the total mass of the aluminum sulfate solution as 100%, the aluminum sulfate solution contains 2-6 wt% Al2O3.

[0039] Furthermore, based on the total mass of the sodium aluminate solution B as 100%, the sodium aluminate solution B contains 8-12 wt% Al2O3 and 8-15 wt% Na2O; based on the total mass of the water glass solution B as 100%, the water glass solution A contains 25-30 wt% SiO2; and based on the total mass of the aluminum sulfate solution as 100%, the aluminum sulfate solution contains 3-5 wt% Al2O3.

[0040] According to a preferred embodiment of the first aspect, the method for preparing the molecular sieve composite material further includes:

[0041] The solid Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide material obtained by solid-liquid separation of Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide slurry was treated with steam.

[0042] Furthermore, the temperature of the steam treatment is 500-800℃; even further, the temperature of the steam treatment is 600-700℃;

[0043] Furthermore, the steam treatment time is 0.5-2.5 hours; even further, the steam treatment time is 1-1.5 hours.

[0044] Furthermore, the preparation method of the molecular sieve composite material also includes: treating the steam-treated Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material with a mixed solution of ammonium sulfate and citric acid;

[0045] Furthermore, taking the total mass of the mixed solution of ammonium sulfate and citric acid as 100%, the mass concentration of ammonium sulfate in the mixed solution of ammonium sulfate and citric acid is 10-20% and the mass concentration of citric acid is 10-20%; further still, taking the total mass of the mixed solution of ammonium sulfate and citric acid as 100%, the mass concentration of ammonium sulfate in the mixed solution of ammonium sulfate and citric acid is 10-15% and the mass concentration of citric acid is 10-15%.

[0046] Furthermore, the treatment time with the mixed solution of ammonium sulfate and citric acid is 0.5-2 hours; even further, the treatment time with the mixed solution of ammonium sulfate and citric acid is 0.5-1 hour.

[0047] Furthermore, the treatment temperature for the mixed solution of ammonium sulfate and citric acid is room temperature.

[0048] Secondly, the present invention provides a molecular sieve composite material prepared by the method for preparing the molecular sieve composite material provided in the first aspect.

[0049] The molecular sieve composite material provided in the second aspect of the present invention is a microporous-mesoporous molecular sieve composite material.

[0050] According to a preferred embodiment of the second aspect, the specific surface area of ​​the molecular sieve composite material is 650-780 m². 2 / g, total pore volume is 0.5-0.72mL / g, pore size distribution is 4-25nm, and infrared acidity is 0.9-1.4mmol / g.

[0051] Thirdly, the present invention provides the application of the molecular sieve composite material provided in the second aspect in the preparation of catalyst supports for the hydrocracking of aromatic distillate oils to produce light naphtha and heavy naphtha.

[0052] The technical method provided by this invention involves crystallizing a mixture of La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, Y molecular sieve directing agent, organic matter (hydroxypropyl methylcellulose, polyethylene glycol, and hexadecyltrimethylammonium bromide) with a silica-alumina base source to construct a structure with a surface area of ​​600-850 m². 2 This is a microporous-mesoporous Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide with a total pore volume of 0.45-0.8 mL / g, a pore size distribution of 4-25 nm, and an infrared acidity of 0.8-1.5 mmol / g. This microporous-mesoporous Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide exhibits high mesoporous pore size distribution, high infrared acidity, selective cracking performance for high-aromatic inferior distillate oils, and the ability to achieve high yields of light naphtha and heavy naphtha through hydrocracking. Detailed Implementation

[0053] To provide a clearer understanding of the technical features, objectives, and beneficial effects of this invention, the technical solution of this invention is described in detail below. However, this should not be construed as limiting the scope of implementation of this invention. Those skilled in the art can make some non-essential improvements and adjustments to this invention based on the above description. Unless otherwise specified, the raw materials used in the following embodiments and comparative examples are commercially available.

[0054] Example 1

[0055] This embodiment provides a molecular sieve composite material, which is prepared by the following method:

[0056] (1) 87g of sodium aluminate solution (Al2O3 content is 4wt%, Na2O content is 20wt%) and 120g of water glass solution (SiO2 content is 20wt%) were added sequentially to 35g of deionized water (i.e. 8.2Na2O:1Al2O3:11.7SiO2:321H2O), and aged at 20℃ for 24h to obtain Y molecular sieve directing agent;

[0057] (2) According to the feeding mass ratio of KIT-6 molecular sieve: lanthanum nitrate: phosphomolybdenum heteropolyacid: H2O = 1:0.01:0.1:0.5, KIT-6 molecular sieve was spray-adsorbed with a complex aqueous solution of phosphomolybdenum heteropolyacid containing lanthanum nitrate. After drying (drying temperature is 80℃, time is 2h) and calcination (calcination temperature is 300℃, time is 2h, atmosphere is air), La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide was obtained.

[0058] (3) Add 5g of La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, 5g of Y molecular sieve directing agent, 80g of aluminum sulfate solution (Al2O3 content is 2wt%), 80g of sodium aluminate solution (Al2O3 content is 5wt%, Na2O content is 5wt%) and 2g of PEG2000 to 90g of water glass solution (SiO2 content is 20wt%), stir evenly, and then add 5g of deionized water to make mixture A. Mixture A is crystallized at 95℃ for 24h to obtain a slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide. The slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide is subjected to solid-liquid separation to obtain solid Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide.

[0059] (4) The Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide obtained in step (3) was treated with water vapor at 800℃ for 0.5 hours.

[0060] (5) The Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide obtained in step (4) after steam treatment is treated at room temperature for 2 hours in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 10wt%, citric acid concentration 10wt%) to obtain the molecular sieve composite material.

[0061] Example 2

[0062] This embodiment provides a molecular sieve composite material, which is prepared by the following method:

[0063] (1) 77g sodium aluminate solution (Al2O3 content is 6wt%, Na2O content is 25wt%) and 100g water glass solution (SiO2 content is 30wt%) were added sequentially to 65g deionized water (i.e. 6.8Na2O:1Al2O3:11.0SiO2:230.8H2O), and aged at 30℃ for 18h to obtain Y molecular sieve directing agent;

[0064] (2) According to the feeding mass ratio of KIT-6 molecular sieve: lanthanum nitrate: phosphomolybdenum heteropoly acid: H2O = 1:0.06:0.13:1, KIT-6 molecular sieve was spray-adsorbed with a complex aqueous solution of phosphomolybdenum heteropoly acid containing lanthanum nitrate. After drying (drying temperature is 90℃, time is 1.5h) and calcining (calcining temperature is 350℃, time is 1.5h, atmosphere is air), La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide was obtained.

[0065] (3) 10g of La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, 10g of Y molecular sieve directing agent, 65g of aluminum sulfate solution (3wt% Al2O3 content), 65g of sodium aluminate solution (10wt% Al2O3 content and 12.5wt% Na2O content) and 5g of PEG200 were added to 75g of water glass solution (27wt% SiO2 content), stirred evenly, and then 50g of deionized water was added to prepare mixture A. Mixture A was crystallized at 95℃ for 36h to obtain a slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide. The slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide was subjected to solid-liquid separation to obtain solid Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide.

[0066] (4) The Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide obtained in step (3) is treated with water vapor at 800℃ for 1 hour.

[0067] (5) The Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide obtained in step (4) after steam treatment is treated at room temperature for 2 hours in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 15wt%, citric acid concentration 15wt%) to obtain the molecular sieve composite material.

[0068] Example 3

[0069] This embodiment provides a molecular sieve composite material, which is prepared by the following method:

[0070] (1) 65g of sodium aluminate solution (Al2O3 content is 8wt%, Na2O content is 30wt%) and 82g of water glass solution (SiO2 content is 40wt%) were added sequentially to 100g of deionized water (i.e. 6.2Na2O:1Al2O3:10.7SiO2:206H2O), and aged at 40℃ for 24h to obtain Y molecular sieve directing agent;

[0071] (2) According to the feeding mass ratio of KIT-6 molecular sieve: lanthanum nitrate: phosphomolybdenum heteropoly acid: H2O = 1:0.12:0.25:2, KIT-6 molecular sieve was spray-adsorbed with a complex aqueous solution of phosphomolybdenum heteropoly acid containing lanthanum nitrate. After drying (drying temperature is 100℃, time is 1h) and calcination (calcination temperature is 400℃, time is 1h, atmosphere is air), La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide was obtained.

[0072] (3) 15g of La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, 15g of Y molecular sieve directing agent, 70g of aluminum sulfate solution (Al2O3 content is 6wt%), 40g of sodium aluminate solution (Al2O3 content is 15wt%, Na2O content is 20wt%) and 7g of CATB were added to 63g of water glass solution (SiO2 content is 40wt%), stirred evenly, and then 82g of deionized water was added to prepare mixture A. Mixture A was crystallized at 100℃ for 48h to obtain a slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide. The slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide was subjected to solid-liquid separation to obtain solid Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide, which is the molecular sieve composite material.

[0073] (4) The Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide obtained in step (3) was treated with water vapor at 800℃ for 0.5 hours.

[0074] (5) The Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide obtained in step (4) after steam treatment is treated at room temperature for 2 hours in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 20wt%, citric acid concentration 20wt%) to obtain the molecular sieve composite material.

[0075] Comparative Example 1

[0076] This comparative example provides a molecular sieve material that differs from Example 3 in that it does not contain La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide. Specifically, it is prepared using the following method:

[0077] (1) 65g of sodium aluminate solution (Al2O3 content is 8wt%, Na2O content is 30wt%) and 82g of water glass solution (SiO2 content is 40wt%) were added sequentially to 100g of deionized water (i.e. 6.2Na2O:1Al2O3:10.7SiO2:206H2O), and aged at 40℃ for 24h to obtain Y molecular sieve directing agent;

[0078] (2) 15g of Y molecular sieve directing agent, 70g of aluminum sulfate solution (Al2O3 content is 6wt%), 40g of sodium aluminate solution (Al2O3 content is 15wt%, Na2O content is 20wt%) and 7g of CATB are added to 63g of water glass solution (SiO2 content is 40wt%), stirred evenly, and then 82g of deionized water is added to make mixture A. Mixture A is crystallized at 100℃ for 48h to obtain Y molecular sieve slurry. The Y molecular sieve slurry is then subjected to solid-liquid separation to obtain solid Y molecular sieve.

[0079] (4) The Y molecular sieve obtained in step (3) is treated with water vapor at 800℃ for 0.5 hours.

[0080] (5) The Y molecular sieve obtained in step (4) after steam treatment is treated at room temperature for 2 hours in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 20wt%, citric acid concentration 20wt%) to obtain the molecular sieve material.

[0081] Comparative Example 2

[0082] This comparative example provides a molecular sieve composite material, which differs from Example 3 in that it uses Beta zeolite and La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve to co-assemble a Beta / La2O3 / PMo heteropolyacid / KIT-6 micro-mesoporous composite molecular sieve, which is prepared by the following method:

[0083] (1) Synthesis of Y molecular sieve directing agent: 65g sodium aluminate solution A (Al2O3 content is 8wt%, Na2O content is 30wt%) and 82g water glass solution (SiO2 content is 40wt%) were added to 100g deionized water in sequence and aged at 40℃ for 24h to obtain Y molecular sieve directing agent. The molar ratio of each component in Y molecular sieve directing agent is 6Na2O:Al2O3:11SiO2:206H2O.

[0084] (2) Beta / La2O3 / PMo heteropolyacid / KIT-6 micro-mesoporous composite molecular sieve was prepared using the preparation method of Example 1 of CN106311319A: 1.9g NaOH and 7.6g NaAlO2 were added to 295g TEAOH solution in sequence and stirred vigorously to mix evenly. Then, 215g TEOS was slowly added and stirred at room temperature for 4h. The mixture was then transferred to a self-pressurized reactor and crystallized at 120℃ for 24h to obtain Beta zeolite seed solution. 2g of P123 was added to 80g of 1mol / L HCl solution, followed by 30g of n-butanol. After stirring for 4 hours, 50g of TEOS was added, and stirring was continued at 40℃ for 2 hours. Then, 80g of the previously prepared Beta zeolite seed solution was added, followed by 5g of La2O3 / PMo heteropolyacid / KIT-6 molecular sieve. The mixture was stirred at 40℃ for 24 hours, then transferred to a self-pressurized reactor and crystallized at 100℃ for 24 hours. After filtration, washing, drying, and calcination at 550℃, the Beta / La2O3 / PMo heteropolyacid / KIT-6 micro-mesoporous composite molecular sieve was finally obtained.

[0085] (3) 15g of Beta / La2O3 / PMo heteropoly acid / KIT-6 micro-mesoporous composite molecular sieve, 15g of Y molecular sieve directing agent, 70g of aluminum sulfate solution (Al2O3 content is 6wt%), 40g of sodium aluminate solution B (Al2O3 content is 15wt%, Na2O content is 20wt%) and 2g of CATB obtained in step (2) are added to 63g of water glass solution (SiO2 content is 40wt%), stirred evenly, and then 82g of deionized water is added to make mixture A. Mixture A is crystallized at 100℃ for 48h to obtain a slurry of Y / Beta / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide. The slurry of Y / Beta / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide is subjected to solid-liquid separation to obtain solid Y / Beta / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide.

[0086] (4) The Y / Beta / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide obtained in step (3) is treated with water vapor at 800℃ for 0.5 hours.

[0087] (5) The Y / Beta / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide after water vapor treatment was treated in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 20wt%, citric acid concentration 20wt%) at room temperature for 2 hours to obtain the molecular sieve composite material.

[0088] Evaluation Example 1

[0089] The specific surface area, pore volume, pore size distribution, and infrared acid content of the molecular sieve composite materials provided in Examples 1-3 and Comparative Examples 1-2 were tested respectively, and the results are shown in Table 1.

[0090] Table 1

[0091]

[0092] Evaluation Example 2

[0093] The performance of the molecular sieve composite materials provided in Examples 1-3 and Comparative Examples 1-2 was evaluated using the feed oils listed in Table 2. The reaction conditions and evaluation results are shown in Table 3.

[0094] In the performance evaluation of the molecular sieve composite material provided in Example 1, the molecular sieve composite material provided in Example 1 was used to prepare a hydrocracking catalyst: the molecular sieve composite material provided in Example 1 was mixed with amorphous aluminum phosphate, phosphomolybdate heteropoly acid powder, and macroporous alumina binder (based on the total mass of the mixture being 100%, the amount of amorphous aluminum phosphate added was 20 wt%, the amount of phosphomolybdate heteropoly acid powder added was 1 wt%, and the amount of macroporous alumina binder added was 20 wt%), and after kneading, rolling, and extrusion molding, a hydrocracking catalyst support was obtained; the hydrocracking catalyst support was mixed with nano nickel oxide powder and nano tungsten oxide powder, and an alumina binder was added, and after rolling and molding, it was calcined at 550°C for 3 hours to obtain the hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst support, nano nickel oxide powder, nano tungsten oxide powder, and alumina binder being 100%, the amount of nano tungsten oxide powder added was 25 wt%, the amount of nano nickel oxide powder added was 2 wt%, and the amount of alumina binder added was 20 wt%.

[0095] In the performance evaluation of the molecular sieve composite material provided in Example 2, the molecular sieve composite material provided in Example 2 was used to prepare a hydrocracking catalyst: the molecular sieve composite material provided in Example 2 was mixed with amorphous aluminum phosphate, phosphomolybdate heteropoly acid powder, and macroporous alumina binder (based on the total mass of the mixture as 100%, the amount of amorphous aluminum phosphate added was 15 wt%, the amount of phosphomolybdate heteropoly acid powder added was 2.5 wt%, and the amount of macroporous alumina binder added was 18 wt%), and after kneading, rolling, and extrusion molding, the following was obtained: Hydrocracking catalyst support; the hydrocracking catalyst support is mixed with nano-nickel oxide powder and nano-tungsten oxide powder, an alumina binder is added, and the mixture is rolled into shape and calcined at 500°C for 4 hours to obtain the hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst support, nano-nickel oxide powder, nano-tungsten oxide powder, and alumina binder as 100%, the amount of nano-tungsten oxide powder added is 21.5 wt%, the amount of nano-nickel oxide powder added is 3.5 wt%, and the amount of alumina binder added is 22.5 wt%.

[0096] In the performance evaluation of the molecular sieve composite material provided in Example 3, the molecular sieve composite material provided in Example 3 was used to prepare a hydrocracking catalyst: the molecular sieve composite material provided in Example 3 was mixed with amorphous aluminum phosphate, phosphomolybdate heteropoly acid powder, and macroporous alumina binder (based on the total mass of the mixture being 100%, the amount of amorphous aluminum phosphate added was 10 wt%, the amount of phosphomolybdate heteropoly acid powder added was 5 wt%, and the amount of macroporous alumina binder added was 15 wt%), and after kneading, rolling, and extrusion molding, a hydrocracking catalyst support was obtained; the hydrocracking catalyst support was mixed with nano nickel oxide powder and nano tungsten oxide powder, and an alumina binder was added, and after rolling and molding, it was calcined at 580°C for 2 hours to obtain the hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst support, nano nickel oxide powder, nano tungsten oxide powder, and alumina binder being 100%, the amount of nano tungsten oxide powder added was 25 wt%, the amount of nano nickel oxide powder added was 2 wt%, and the amount of alumina binder added was 25 wt%.

[0097] In the performance evaluation of the molecular sieve material provided in Comparative Example 1, a hydrocracking catalyst was prepared using the molecular sieve material provided in Comparative Example 1: The molecular sieve material provided in Comparative Example 1 was mixed with amorphous aluminum phosphate, phosphomolybdate heteropoly acid powder, and macroporous alumina binder (based on the total mass of the mixture being 100%, the amount of amorphous aluminum phosphate added was 10 wt%, the amount of phosphomolybdate heteropoly acid powder added was 5 wt%, and the amount of macroporous alumina binder added was 15 wt%). After kneading, rolling, and extrusion molding, a hydrocracking catalyst support was obtained. The hydrocracking catalyst support was mixed with nano-nickel oxide powder and nano-tungsten oxide powder, and an alumina binder was added. After rolling and molding, it was calcined at 580°C for 2 hours to obtain the hydrocracking catalyst. Based on the total mass of the hydrocracking catalyst support, nano-nickel oxide powder, nano-tungsten oxide powder, and alumina binder being 100%, the amount of nano-tungsten oxide powder added was 25 wt%, the amount of nano-nickel oxide powder added was 2 wt%, and the amount of alumina binder added was 25 wt%.

[0098] In the performance evaluation of the molecular sieve composite material provided in Comparative Example 2, the molecular sieve composite material provided in Comparative Example 2 was used to prepare a hydrocracking catalyst: the molecular sieve composite material provided in Comparative Example 2 was mixed with amorphous aluminum phosphate, phosphomolybdenum heteropoly acid powder, and macroporous alumina binder (based on the total mass of the mixture being 100%, the amount of amorphous aluminum phosphate added was 10 wt%, the amount of phosphomolybdenum heteropoly acid powder added was 5 wt%, and the amount of macroporous alumina binder added was 15 wt%), and after kneading, rolling, and extrusion molding, a hydrocracking catalyst support was obtained; the hydrocracking catalyst support was mixed with nano nickel oxide powder and nano tungsten oxide powder, and alumina binder was added, rolled and calcined at 580℃ for 2 hours to obtain the hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst support, nano nickel oxide powder, nano tungsten oxide powder, and alumina binder being 100%, the amount of nano tungsten oxide powder added was 25 wt%, the amount of nano nickel oxide powder added was 2 wt%, and the amount of alumina binder added was 25 wt%.

[0099] Table 2 Properties of Crude Oil

[0100]

[0101] Table 3 Reaction performance of hydrocracking catalysts

[0102]

[0103]

[0104] As can be seen from the results in Tables 1 and 3, the molecular sieve composite material prepared by the method of the present invention improves the mesopore size distribution and infrared acidity. When used in hydrocracking to produce more light naphtha and heavy naphtha, it improves the selective cracking performance of distillate oil and increases the yield of light naphtha and heavy naphtha.

[0105] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a molecular sieve composite material, wherein, The preparation method includes: KIT-6 molecular sieve was spray-adsorbed with a lanthanum salt-containing phosphomolybdic acid complex aqueous solution, and then dried and calcined to obtain La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide. According to the mass ratio of (0.8-1.5) La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide : (0.08 – 1.5) Y molecular sieve directing agent : 1 Al2O3 : (0.08-1.0) Na2O : (2.3-3.3) SiO2 : (0.3-0.7) organic matter : (13-41) H2O, La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, Y molecular sieve directing agent, aluminum source, sodium source, silicon source, organic matter and water are mixed to obtain mixture A. Mixture A is crystallized to obtain a slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide. The slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide is subjected to solid-liquid separation to obtain solid Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material, which is the molecular sieve composite material. Among them, sodium source, aluminum source, silicon source and water are mixed according to the molar ratio of (6-9)Na2O:1Al2O3: (7-13)SiO2: (200-350)H2O, and then aged to obtain Y molecular sieve directing agent; The organic compound includes at least one of hydroxypropyl methylcellulose, polyethylene glycol, and hexadecyltrimethylammonium bromide.

2. The preparation method according to claim 1, wherein, The lanthanum salt is selected from lanthanum nitrate; in the preparation process of La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, the mass ratio of KIT-6 molecular sieve to lanthanum nitrate to phosphomolybdenum heteropoly acid to water is 1: (0.01-0.12): (0.1-0.25): (0.5-2).

3. The preparation method according to claim 2, wherein, KIT-6 molecular sieve mass: Lanthanum nitrate mass: Phosphomolybdic acid mass: Water mass = 1: (0.05-0.1): (0.15-0.2): (0.5-2).

4. The preparation method according to claim 1, wherein, The aging temperature is 20-60℃.

5. The preparation method according to claim 3, wherein, The aging temperature is 25-40℃.

6. The preparation method according to claim 1, wherein, Sodium source, aluminum source, silicon source and water were mixed according to the molar ratio of (6.5-7.5)Na2O:1Al2O3: (9-11)SiO2:(220-300)H2O, and then aged to obtain Y molecular sieve directing agent.

7. The preparation method according to claim 1, wherein, The aluminum source used in the preparation of Y molecular sieve directing agents includes at least one of aluminum sulfate and sodium aluminate.

8. The preparation method according to claim 1, wherein, Sodium sources used in the preparation of Y molecular sieve directing agents include sodium aluminate.

9. The preparation method according to claim 1, wherein, The silicon source used to prepare the Y molecular sieve directing agent includes at least one of water glass and silica sol.

10. The preparation method according to claim 1, wherein, Methods for preparing molecular sieve composite materials also include: The solid phase Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide material obtained by solid-liquid separation of the slurry of Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide was treated with steam.

11. The preparation method according to claim 10, wherein, The temperature for steam treatment is 500-800℃.

12. The preparation method according to claim 11, wherein, The temperature for the steam treatment is 600-700℃.

13. The preparation method according to claim 10, wherein, The preparation method of molecular sieve composite materials also includes: treating the Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material after steam treatment with a mixed solution of ammonium sulfate and citric acid.

14. The preparation method according to claim 13, wherein, Taking the total mass of the mixed solution of ammonium sulfate and citric acid as 100%, the mass concentration of ammonium sulfate in the mixed solution of ammonium sulfate and citric acid is 10-20%, and the mass concentration of citric acid is 10-20%.

15. The preparation method according to claim 14, wherein, Taking the total mass of the mixed solution of ammonium sulfate and citric acid as 100%, the mass concentration of ammonium sulfate in the mixed solution of ammonium sulfate and citric acid is 10-15% and the mass concentration of citric acid is 10-15%.

16. The preparation method according to claim 1, wherein, The crystallization temperature is 90-100℃.

17. The preparation method according to claim 16, wherein, The crystallization temperature is 95-100℃.

18. The preparation method according to claim 1, wherein, During the preparation of La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, the calcination temperature is 300-400℃.

19. The preparation method according to claim 1, wherein, During the preparation of La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, the calcination atmosphere is air.

20. The preparation method according to claim 1, wherein, The polyethylene glycol includes at least one of PEG2000 and PEG200.

21. The preparation method according to claim 1, wherein, The lanthanum salt is selected from lanthanum nitrate.

22. The preparation method according to claim 1, wherein, The aluminum source used to prepare mixture A includes at least one of aluminum sulfate and sodium aluminate.

23. The preparation method according to claim 1, wherein, The sodium source used to prepare mixture A includes sodium aluminate.

24. The preparation method according to claim 1, wherein, The silicon source used to prepare mixture A includes at least one of water glass and silica sol.

25. The molecular sieve composite material prepared by the method of any one of claims 1-24.

26. The molecular sieve composite material according to claim 25, wherein, The specific surface area of ​​this molecular sieve composite material is 650-780 m². 2 / g, total pore volume is 0.5-0.72mL / g, pore size distribution is 4-25nm, and infrared acidity is 0.9-1.4mmol / g.

27. The application of the molecular sieve composite material according to claim 25 or 26 in the preparation of catalyst support for the hydrocracking of aromatic distillate oil to produce light naphtha and heavy naphtha.

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