Hydrocracking catalyst as well as preparation method and application thereof

Abstract

The invention provides a hydrocracking catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, a Y molecular sieve guiding agent, an organic matter, an aluminum source, an alkali source, a silicon source and water to obtain a mixture A, crystallizing the mixture A, and performing solid-liquid separation to obtain a molecular sieve composite material; mixing the molecular sieve composite material with amorphous phosphorus aluminum, phosphorus molybdenum heteropoly acid and a macroporous binder to obtain a mixture B, and forming the mixture B to obtain a catalyst carrier; mixing the catalyst carrier with the nano metal oxide and the binder to obtain a mixture C, and forming and roasting the mixture C to obtain the hydrocracking catalyst. The hydrocracking catalyst has high aromatic hydrocarbon inferior distillate oil selective cracking performance, and can realize the yield of hydrocracking high light naphtha and heavy naphtha.

Description

Technical Field

[0001] The invention belongs to the technical field of catalyst material preparation, and in particular relates to a hydrocracking catalyst suitable for preparing light naphtha and heavy naphtha by hydrocracking, and a preparation method and application thereof. Background Art

[0002] Molecular sieves are widely used in adsorption, separation, catalysis and other fields due to their unique pore structure, especially in petrochemicals. With the continuous development of molecular sieve catalytic applications, molecular sieves with a single pore can no longer meet the various catalyst preparation requirements. Microporous molecular sieves are mainly known for their strong acid properties and high structural stability in heterogeneous catalytic applications. However, since most microporous molecular sieves have small pore sizes and long and narrow pores, it is difficult for the macromolecules in the reaction raw materials, such as heavy oil, to diffuse into the pores, which will reduce the utilization rate of the acid sites inside the microporous molecular sieve pores. At the same time, the narrow and long pores have a large diffusion resistance, which affects the rapid diffusion and overflow of the reaction product molecules, and easily leads to deep cracking and coking. Although mesoporous molecular sieves can make up for the limitations of microporous molecular sieves in the diffusion of reactants and reaction products, the structural stability of mesoporous molecular sieves is often poor, which also limits their catalytic applications. Microporous-mesoporous composite molecular sieve materials can produce good synergistic effects and catalytic performance by complementing the strengths of several single materials, making their overall performance better than the original component materials. This molecular sieve with multiple structures and superimposed functions can avoid the defects of a single pore structure, and 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 large molecules.

[0003] CN111484037A discloses a method for synthesizing SSZ-13 molecular sieves with different silicon-aluminum ratios by crystallization of Y molecular sieves, wherein TMADaOH is used as a structure directing agent, an alkali source, a silicon source, a structure directing agent, a mesoporous template agent and water are uniformly mixed, different amounts of aluminum sources are added to obtain a sol, and then a Y-type molecular sieve is added to obtain an initial gel, and a hydrothermal crystallization reaction is performed. After the reaction is completed, a crystallization reaction product is obtained, which is cooled and washed to neutrality, and dried to obtain a molecular sieve raw powder, and then the molecular sieve raw powder is roasted to obtain SSZ-13 molecular sieves with different silicon-aluminum ratios. However, the pore size and pore volume of the SSZ-13 molecular sieve obtained by this method are relatively low, the selective cracking performance of low-quality aromatic fraction oil is poor, and the yield of preparing light naphtha and heavy naphtha by hydrocracking is low, and it is not suitable for preparing light naphtha and heavy naphtha by hydrocracking.

[0004] CN110357121A discloses a method for preparing a small-grain nanometer multi-level pore SSZ-13 molecular sieve, which uses TMADaOH as a structure-directing agent and TPOAC as a mesoporous template agent, uniformly mixes an alkali source, a silicon source, a structure-directing agent, a mesoporous template agent and water, adds or does not add an aluminum source to obtain a sol, then adds a Y-type molecular sieve to obtain an initial gel, performs a hydrothermal crystallization reaction, and calcines the reaction product to obtain a small-grain nanometer multi-level pore SSZ-13 molecular sieve. However, the SSZ-13 molecular sieve synthesized by the method has poor selective cracking performance for low-quality aromatic distillate oil, and has a low yield for preparing light naphtha and heavy naphtha by hydrocracking, and is not suitable for preparing light naphtha and heavy naphtha by hydrocracking.

[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, the Y / SSZ-13 / rare earth / ASA composite material has poor selective cracking performance of low-quality aromatic fraction oil, and has low yield of preparing light naphtha and heavy naphtha by hydrocracking, and is not suitable for preparing light naphtha and heavy naphtha by hydrocracking.

[0006] CN106311319A discloses a hydrocracking catalyst containing a micro-mesoporous composite molecular sieve, wherein the catalyst is a micro-mesoporous composite Beta / KIT-6 composite molecular sieve. The composite molecular sieve has low acid strength, poor selective cracking performance of low-quality aromatic fraction oil, and low yield of light naphtha and heavy naphtha prepared by hydrocracking, and is not suitable for preparing light naphtha and heavy naphtha by hydrocracking.

[0007] In short, the existing molecular sieves generally have the problem of poor selective cracking performance of aromatic inferior distillate oil and low yield of light naphtha and heavy naphtha produced by hydrocracking in the process of preparing light naphtha and heavy naphtha by hydrocracking. Therefore, it is still necessary to study a hydrocracking catalyst with high selective cracking performance of aromatic inferior distillate oil and capable of achieving high light naphtha and heavy naphtha yield by hydrocracking. Summary of the invention

[0008] The object of the present invention is to provide a hydrocracking catalyst having high aromatic inferior distillate oil selective cracking performance and capable of achieving high light naphtha and heavy naphtha yields by hydrocracking, as well as a method for preparing the hydrocracking catalyst and the application of the hydrocracking catalyst.

[0009] In order 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 hydrocracking catalyst, wherein the method comprises:

[0011] The KIT-6 molecular sieve is sprayed with a lanthanum salt-containing phosphomolybdic heteropoly acid complex aqueous solution for adsorption, and then dried and calcined to obtain La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide;

[0012] 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: 1Al2O3: (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, organic matter, aluminum source, alkali source, silicon source and water Y molecular sieve directing agent, La2O3 / PMo heteropoly acid / KIT-6 A mesoporous molecular sieve oxide, an organic matter, an aluminum source, an alkali source, a silicon source and water are mixed to obtain a mixture A, the mixture A is crystallized to obtain a slurry of a Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide, and the Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide slurry is subjected to solid-liquid separation to obtain a solid-phase Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material, which is the molecular sieve composite material; wherein the organic matter comprises at least one of hydroxypropyl methylcellulose, polyethylene glycol and cetyltrimethylammonium bromide;

[0013] The molecular sieve composite material is mixed with amorphous aluminum phosphide, phosphomolybdic heteropoly acid, and a macroporous binder to obtain a mixture B, and the mixture B is formed to obtain a catalyst carrier;

[0014] The catalyst carrier is mixed with the nano metal oxide and the binder to obtain a mixture C, and the mixture C is formed and calcined to obtain a hydrocracking catalyst.

[0015] The technical solution provided by the present invention is to mix La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, Y molecular sieve directing agent, organic matter (hydroxypropyl methylcellulose, polyethylene glycol and hexadecyl trimethyl ammonium bromide) with a silicon aluminum alkali source and then crystallize to obtain a special Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve mesoporous composite oxide material, the Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve mesoporous composite oxide material has a microporous-mesoporous composite structure, a high mesopore pore size distribution, and a high infrared acid content. The carrier prepared by using the material and then the hydrocracking catalyst prepared have high aromatics low-quality distillate oil selective cracking performance, and can achieve high light naphtha and heavy naphtha yields by hydrocracking.

[0016] According to a preferred embodiment of the first aspect, the polyethylene glycol includes at least one of PEG2000 and PEG200.

[0017] According to a preferred embodiment of the first aspect, the lanthanum salt is lanthanum nitrate.

[0018] According to a preferred embodiment of the first aspect, the aluminum source includes at least one of aluminum sulfate and sodium aluminate.

[0019] According to a preferred embodiment of the first aspect, the alkali source includes at least one of sodium aluminate and potassium hydroxide.

[0020] According to a preferred embodiment of the first aspect, the silicon source includes at least one of water glass and silica sol.

[0021] According to a preferred embodiment of the first aspect, the Y molecular sieve directing agent is prepared by the following method:

[0022] An alkali source, an aluminum source, a silicon source and water are mixed according to a molar ratio of (6-9)Na2O:1Al2O3:(7-13)SiO2:(200-350)H2O, and a Y molecular sieve directing agent is obtained by aging;

[0023] Further, the aging temperature is 20-60°C; further, the aging temperature is 25-40°C;

[0024] Further, the aging time is 10-24 hours; further, the aging time is 12-24 hours;

[0025] Further, the aluminum source used in preparing the Y molecular sieve directing agent includes at least one of aluminum sulfate and sodium metaaluminate;

[0026] Further, the alkali source used in preparing the Y molecular sieve directing agent includes at least one of sodium metaaluminate and potassium hydroxide;

[0027] Further, the silicon source used in preparing the Y molecular sieve directing agent includes at least one of water glass and silica sol;

[0028] Further, an alkali source, an aluminum source, a silicon source and water are mixed according to a molar ratio of (6.5-7.5) Na2O:1Al2O3:(9-11)SiO2:(220-300)H2O, and a Y molecular sieve directing agent is obtained by aging;

[0029] Furthermore, sodium aluminate solution A, water glass solution A and water are mixed and aged to obtain a Y molecular sieve directing agent; wherein, based on the total mass of the sodium aluminate solution A being 100%, the Al2O3 content in the sodium aluminate solution A is 4-8wt%, and the Na2O content is 20-30wt%; based on the total mass of the water glass solution A being 100%, the SiO2 content in the water glass solution A is 20-40wt%; further, based on the total mass of the sodium aluminate solution A being 100%, the Al2O3 content in the sodium aluminate solution A is 5-7wt%, and the Na2O content is 25-30wt%; based on the total mass of the water glass solution A being 100%, the SiO2 content in the water glass solution A is 25-30wt%.

[0030] According to a preferred embodiment of the first aspect, in the preparation process of La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, the mass of KIT-6 molecular sieve: the mass of lanthanum nitrate: the mass of phosphomolybdic heteropoly acid: the mass of water = 1: (0.01-0.12): (0.1-0.25): (0.5-2);

[0031] Furthermore, the mass of KIT-6 molecular sieve: the mass of lanthanum nitrate: the mass of phosphomolybdic heteropoly acid: the mass of water = 1: (0.05-0.1): (0.15-0.2): (0.5-2).

[0032] According to a preferred embodiment of the first aspect, during the preparation of La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, the drying temperature is 80-100°C.

[0033] According to a preferred embodiment of the first aspect, during the preparation of La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, the calcination temperature is 300-400°C.

[0034] According to a preferred embodiment of the first aspect, during the preparation of La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, the calcination atmosphere is an air atmosphere.

[0035] According to a preferred embodiment of the first aspect, the crystallization temperature is 90-100°C; further, the crystallization temperature is 95-100°C.

[0036] According to a preferred embodiment of the first aspect, the crystallization time is 24-48 hours.

[0037] According to a preferred embodiment of the first aspect, La2O3 / PMo heteropoly acid / 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, La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, organic matter, aluminum source, alkali source, silicon source and water are mixed to obtain mixture A by the following method:

[0038] Mixing La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, Y molecular sieve directing agent, organic matter, aluminum sulfate solution, sodium metaaluminate solution B, water glass solution B and water to obtain a mixture A;

[0039] Wherein, based on the total mass of the sodium aluminate solution B being 100%, the content of Al2O3 in the sodium aluminate solution B is 5-15wt%, and the content of Na2O is 5-20wt%; based on the total mass of the water glass solution B being 100%, the content of SiO2 in the water glass solution A is 20-40wt%; based on the total mass of the aluminum sulfate solution being 100%, the content of Al2O3 in the aluminum sulfate solution is 2-6wt%;

[0040] Furthermore, based on the total mass of the sodium aluminate solution B being 100%, the Al2O3 content in the sodium aluminate solution B is 8-12wt%, and the Na2O content is 8-15wt%; based on the total mass of the water glass solution B being 100%, the SiO2 content in the water glass solution A is 25-30wt%; based on the total mass of the aluminum sulfate solution being 100%, the Al2O3 content in the aluminum sulfate solution is 3-5wt%.

[0041] According to a preferred embodiment of the first aspect, the preparation method further comprises:

[0042] The solid phase Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material is treated with water vapor before preparing the mixture B;

[0043] Further, the temperature of the water vapor treatment is 500-800°C; further, the temperature of the water vapor treatment is 600-700°C;

[0044] Further, the time of the water vapor treatment is 0.5-2.5h; further, the time of the water vapor treatment is 1-1.5h;

[0045] Furthermore, the preparation method further comprises: treating the Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material after the water vapor treatment with a mixed solution of ammonium sulfate and citric acid, and then using the mixed solution to prepare the mixture B;

[0046] Furthermore, based on 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, based on 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%;

[0047] Furthermore, the treatment time of the mixed solution of ammonium sulfate and citric acid is 0.5-2h; further, the treatment time of the mixed solution of ammonium sulfate and citric acid is 0.5-1h;

[0048] Furthermore, the treatment temperature of the mixed solution of ammonium sulfate and citric acid is room temperature.

[0049] According to a preferred embodiment of the first aspect, the macroporous binder used to prepare the mixture B is a macroporous alumina binder.

[0050] According to a preferred embodiment of the first aspect, the molding of the mixture B is achieved by the following methods: kneading, rolling, and extrusion molding.

[0051] According to a preferred embodiment of the first aspect, the amount of amorphous phosphorus aluminum added is 10-20wt% based on 100% mass of mixture B; further, the amount of amorphous phosphorus aluminum added is 15-18wt% based on 100% mass of mixture B.

[0052] According to a preferred embodiment of the first aspect, the amount of the phosphomolybdic heteropoly acid added is 1-5wt% based on 100% mass of the mixture B; further, the amount of the phosphomolybdic heteropoly acid added is 2-4wt% based on 100% mass of the mixture B.

[0053] According to a preferred embodiment of the first aspect, based on 100% by mass of the mixture B, the amount of the macroporous binder added is 15-20 wt%. Further, based on 100% by mass of the mixture B, the amount of the macroporous binder added is 17-18 wt%.

[0054] According to a preferred embodiment of the first aspect, the nano metal oxide comprises nano tungsten oxide and nano nickel oxide;

[0055] Further, based on 100% by mass of the mixture C, the amount of nano-tungsten oxide added is 18-25wt%; further, based on 100% by mass of the mixture C, the amount of nano-tungsten oxide added is 20-23wt%;

[0056] Furthermore, based on 100% by mass of the mixture C, the amount of nano-nickel oxide added is 2-5wt%; further, based on 100% by mass of the mixture C, the amount of nano-nickel oxide added is 3-4wt%.

[0057] According to a preferred embodiment of the first aspect, the binder used to prepare the mixture C is an alumina binder.

[0058] According to a preferred embodiment of the first aspect, the amount of the binder added is 20-25wt%, based on 100% by mass of the mixture C.

[0059] According to a preferred embodiment of the first aspect, in the process of forming and calcining the mixture C to obtain the hydrocracking catalyst, the calcination temperature is 450-650°C.

[0060] According to a preferred embodiment of the first aspect, in the process of forming and calcining the mixture C to obtain the hydrocracking catalyst, the calcination time is 1.5-3.5 hours.

[0061] According to a preferred embodiment of the first aspect, during the process of molding and calcining the mixture C to obtain the hydrocracking catalyst, the calcination atmosphere is an air atmosphere.

[0062] In a second aspect, the present invention provides a hydrocracking catalyst prepared by the method for preparing the hydrocracking catalyst provided in the first aspect.

[0063] According to a preferred embodiment of the second aspect, the specific surface area of ​​the hydrocracking catalyst is 350-400m 2 / g, the total pore volume is 0.3-0.52mL / g, and the pore size distribution is 4-22nm.

[0064] In a third aspect, the present invention provides use of the hydrocracking catalyst provided in the second aspect in the preparation of light naphtha and heavy naphtha by hydrocracking of aromatic fraction oil.

[0065] The technical method provided by the present invention is to mix 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 alkali source and then crystallize to construct a surface area of ​​600-850m 2 / g, a total pore volume of 0.45-0.8mL / g, a pore size distribution of 4-25nm, and an infrared acid content of 0.8-1.5mmol / g of a microporous-mesoporous La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide. The microporous-mesoporous La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide has a high mesopore pore size distribution and a high infrared acid content. The material is used to prepare a carrier and then a hydrocracking catalyst. The specific surface area of ​​the hydrocracking catalyst is 350-400m 2 / g, the total pore volume is 0.3-0.52mL / g, the pore size distribution is 4-22nm, it has the selective cracking performance of high aromatic inferior distillate oil, and can achieve high light naphtha and heavy naphtha yields by hydrocracking. DETAILED DESCRIPTION

[0066] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it cannot be understood as limiting the scope of the present invention. Those skilled in the art in this field can make some non-essential improvements and adjustments to the present invention based on the above content of the present invention. The raw materials used in the following examples and comparative examples, unless otherwise specified, are all commercially available.

[0067] Example 1

[0068] This embodiment provides a hydrocracking catalyst, which is prepared by the following preparation method:

[0069] (1) 87 g of sodium aluminate solution (Al2O3 content of 4 wt%, Na2O content of 20 wt%) and 120 g of water glass solution (SiO2 content of 20 wt%) were added to 35 g of deionized water (i.e., 8.2 Na2O: 1 Al2O3: 11.7 SiO2: 321 H2O) in sequence, and aged at 20° C. for 24 h to obtain a Y molecular sieve directing agent;

[0070] (2) According to the feed mass ratio of KIT-6 molecular sieve: lanthanum nitrate: phosphomolybdic heteropoly acid: H2O=1:0.01:0.1:0.5, the KIT-6 molecular sieve and the phosphomolybdic heteropoly acid complex aqueous solution containing lanthanum nitrate were sprayed for adsorption, and after drying (drying temperature was 80°C, time was 2h) and roasting (roasting temperature was 300°C, time was 2h, atmosphere was air), La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide was obtained;

[0071] (3) 5 g of La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, 5 g of Y molecular sieve directing agent, 80 g of aluminum sulfate solution (Al2O3 content of 2 wt%), 80 g of sodium aluminate solution (Al2O3 content of 5 wt%, Na2O content of 5 wt%) and 2 g of PEG2000 were added to 90 g of water glass solution (SiO2 content of 20 wt%), stirred evenly and then 5 g of deionized water was added to prepare a mixture A, and the mixture A was crystallized at 95° C. for 24 h to obtain a slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide, and the slurry of Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide was subjected to solid-liquid separation to obtain a solid phase Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide;

[0072] (4) The Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide obtained in step (3) is treated under 800°C water vapor conditions for 0.5 hours.

[0073] (5) Treat the Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide treated with water vapor obtained in step (4) in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 10 wt%, citric acid concentration 10 wt%) at room temperature for 2 hours to obtain a treated molecular sieve composite material.

[0074] (6) The treated molecular sieve composite material is mixed with amorphous phosphorus aluminum, phosphomolybdic acid heteropoly powder, and macroporous alumina binder (based on the total mass after mixing as 100%, the amount of amorphous phosphorus aluminum added is 20wt%, the amount of phosphomolybdic acid heteropoly powder added is 1wt%, and the amount of macroporous alumina binder added is 20wt%), and a hydrocracking catalyst carrier is obtained by kneading, rolling, and extrusion.

[0075] (7) A hydrocracking catalyst carrier is mixed with nano nickel oxide powder and nano tungsten oxide powder, an alumina binder is added, the mixture is rolled and calcined at 550° C. for 3 hours to obtain a hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst carrier, the nano nickel oxide powder, the nano tungsten oxide powder and the alumina binder being 100%, the amount of the nano tungsten oxide powder added is 25wt%, the amount of the nano nickel oxide powder added is 2wt%, and the amount of the alumina binder added is 20wt%.

[0076] Example 2

[0077] This embodiment provides a hydrocracking catalyst, which is prepared by the following preparation method:

[0078] (1) 77 g of sodium aluminate solution (with an Al2O3 content of 6 wt %, a Na2O content of 25 wt %) and 100 g of water glass solution (with a SiO2 content of 30 wt %) were sequentially added to 65 g of deionized water (i.e., 6.8 Na2O: 1 Al2O3: 11.0 SiO2: 230.8 H2O), and aged at 30° C. for 18 h to obtain a Y molecular sieve directing agent;

[0079] (2) According to the feed mass ratio of KIT-6 molecular sieve: lanthanum nitrate: phosphomolybdic heteropoly acid: H2O=1:0.06:0.13:1, the KIT-6 molecular sieve and the phosphomolybdic heteropoly acid complex aqueous solution containing lanthanum nitrate were sprayed for adsorption, and after drying (drying temperature was 90°C, time was 1.5h) and calcination (calcination temperature was 350°C, time was 1.5h, atmosphere was air), La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide was obtained;

[0080] (3) 10 g of La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, 10 g of Y molecular sieve directing agent, 65 g of aluminum sulfate solution (Al2O3 content of 3 wt%), 65 g of sodium aluminate solution (Al2O3 content of 10 wt%, Na2O content of 12.5 wt%) and 5 g of PEG200 were added to 75 g of water glass solution (SiO2 content of 27 wt%), stirred evenly and then added with 50 g of deionized water to prepare a mixture A. The mixture A was crystallized at 95°C for 36 h to obtain a slurry of Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide. The slurry of Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide was subjected to solid-liquid separation to obtain a solid phase Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide.

[0081] (4) Treat the Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide obtained in step (3) under 800°C water vapor conditions for 1 hour.

[0082] (5) Treat the Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide treated with water vapor obtained in step (4) in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 15 wt%, citric acid concentration 15 wt%) at room temperature for 2 hours to obtain a treated molecular sieve composite material.

[0083] (6) The treated molecular sieve composite material is mixed with amorphous phosphorus aluminum, phosphomolybdic acid heteropoly powder, and macroporous alumina binder (based on the total mass after mixing as 100%, the amount of amorphous phosphorus aluminum added is 15wt%, the amount of phosphomolybdic acid heteropoly powder added is 2.5wt%, and the amount of macroporous alumina binder added is 18wt%), and a hydrocracking catalyst carrier is obtained by kneading, rolling, and extrusion.

[0084] (7) A hydrocracking catalyst carrier is mixed with nano nickel oxide powder and nano tungsten oxide powder, an alumina binder is added, the mixture is rolled and calcined at 500° C. for 4 hours to obtain a hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst carrier, nano nickel oxide powder, nano tungsten oxide powder and alumina binder being 100%, the amount of nano tungsten oxide powder added is 21.5wt%, the amount of nano nickel oxide powder added is 3.5wt%, and the amount of alumina binder added is 22.5wt%.

[0085] Example 3

[0086] This embodiment provides a hydrocracking catalyst, which is prepared by the following preparation method:

[0087] (1) 65 g of sodium aluminate solution (with an Al2O3 content of 8 wt %, a Na2O content of 30 wt %) and 82 g of water glass solution (with a SiO2 content of 40 wt %) were sequentially added to 100 g of deionized water (i.e., 6.2 Na2O:1 Al2O3:10.7 SiO2:206 H2O), and aged at 40° C. for 24 h to obtain a Y molecular sieve directing agent;

[0088] (2) According to the feed mass ratio of KIT-6 molecular sieve: lanthanum nitrate: phosphomolybdic heteropoly acid: H2O=1:0.12:0.25:2, KIT-6 molecular sieve and phosphomolybdic heteropoly acid complex aqueous solution containing lanthanum nitrate were sprayed for adsorption, and after drying (drying temperature was 100°C, time was 1h) and calcination (calcination temperature was 400°C, time was 1h, atmosphere was air), La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide was obtained;

[0089] (3) 15 g of La2O3 / PMo heteropolyacid / KIT-6 mesoporous molecular sieve oxide, 15 g of Y molecular sieve directing agent, 70 g of aluminum sulfate solution (Al2O3 content of 6 wt%), 40 g of sodium aluminate solution (Al2O3 content of 15 wt%, Na2O content of 20 wt%) and 7 g of CATB are added to 63 g of water glass solution (SiO2 content of 40 wt%), stirred evenly and then added with 82 g of deionized water to prepare a mixture A. The mixture A is crystallized at 100°C for 48 h to obtain a slurry of Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide. The slurry of Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide is subjected to solid-liquid separation to obtain a solid phase Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide, i.e., the molecular sieve composite material.

[0090] (4) The Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide obtained in step (3) is treated under 800°C water vapor conditions for 0.5 hours.

[0091] (5) Treat the Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide treated with water vapor obtained in step (4) in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 20 wt%, citric acid concentration 20 wt%) at room temperature for 2 hours to obtain a treated molecular sieve composite material.

[0092] (6) The treated molecular sieve composite material is mixed with amorphous phosphorus aluminum, phosphomolybdic acid heteropoly powder, and macroporous alumina binder (based on the total mass after mixing as 100%, the amount of amorphous phosphorus aluminum added is 10wt%, the amount of phosphomolybdic acid heteropoly powder added is 5wt%, and the amount of macroporous alumina binder added is 15wt%), and a hydrocracking catalyst carrier is obtained by kneading, rolling, and extrusion.

[0093] (7) A hydrocracking catalyst carrier is mixed with nano nickel oxide powder and nano tungsten oxide powder, an alumina binder is added, the mixture is rolled and calcined at 580° C. for 2 hours to obtain a hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst carrier, nano nickel oxide powder, nano tungsten oxide powder and alumina binder being 100%, the amount of nano tungsten oxide powder added is 25wt%, the amount of nano nickel oxide powder added is 2wt%, and the amount of alumina binder added is 25wt%.

[0094] Comparative Example 1

[0095] This comparative example provides a hydrocracking catalyst, which is different from Example 3 in that La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide is not added, and is specifically prepared by the following preparation method:

[0096] (1) 65 g of sodium aluminate solution (with an Al2O3 content of 8 wt %, a Na2O content of 30 wt %) and 82 g of water glass solution (with a SiO2 content of 40 wt %) were sequentially added to 100 g of deionized water (i.e., 6.2 Na2O:1 Al2O3:10.7 SiO2:206 H2O), and aged at 40° C. for 24 h to obtain a Y molecular sieve directing agent;

[0097] (2) 15 g of Y molecular sieve directing agent, 70 g of aluminum sulfate solution (Al2O3 content of 6 wt%), 40 g of sodium aluminate solution (Al2O3 content of 15 wt%, Na2O content of 20 wt%) and 7 g of CATB were added to 63 g of water glass solution (SiO2 content of 40 wt%), stirred evenly and then added with 82 g of deionized water to prepare a mixture A. The mixture A was crystallized at 100°C for 48 h to obtain a Y molecular sieve slurry. The Y molecular sieve slurry was subjected to solid-liquid separation to obtain a solid phase Y molecular sieve.

[0098] (3) Treat the Y molecular sieve obtained in step (2) under 800° C. steam conditions for 0.5 hour.

[0099] (4) Treat the Y molecular sieve treated with water vapor obtained in step (3) in a mixed solution of ammonium sulfate and citric acid (ammonium sulfate concentration 20 wt%, citric acid concentration 20 wt%) at room temperature for 2 hours to obtain a treated molecular sieve material.

[0100] (5) The treated molecular sieve material is mixed with amorphous phosphoalumina, phosphomolybdic acid heteropoly powder, and macroporous alumina binder (based on the total mass after mixing as 100%, the amount of amorphous phosphoalumina added is 10wt%, the amount of phosphomolybdic acid heteropoly powder added is 5wt%, and the amount of macroporous alumina binder added is 15wt%), and a hydrocracking catalyst carrier is obtained by kneading, rolling, and extrusion.

[0101] (6) A hydrocracking catalyst carrier is mixed with nano nickel oxide powder and nano tungsten oxide powder, an alumina binder is added, the mixture is rolled and calcined at 580° C. for 2 hours to obtain a hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst carrier, nano nickel oxide powder, nano tungsten oxide powder and alumina binder being 100%, the amount of nano tungsten oxide powder added is 25wt%, the amount of nano nickel oxide powder added is 2wt%, and the amount of alumina binder added is 25wt%.

[0102] Comparative Example 2

[0103] This comparative example provides a hydrocracking catalyst, which is different from Example 3 in that Beta zeolite and La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve are co-assembled to obtain Beta / La2O3 / PMo heteropoly acid / KIT-6 micro-mesoporous composite molecular sieve, which is specifically prepared by the following preparation method:

[0104] (1) Synthesis of Y molecular sieve directing agent: 65 g of sodium aluminate solution A (Al2O3 content of 8 wt%, Na2O content of 30 wt%) and 82 g of water glass solution (SiO2 content of 40 wt%) were added to 100 g of deionized water in sequence, and aged at 40°C for 24 h to obtain Y molecular sieve directing agent. The molar ratio of each component in the Y molecular sieve directing agent was 6Na2O:Al2O3:11SiO2:206H2O.

[0105] (2) Beta / La2O3 / PMo heteropolyacid / KIT-6 micro-mesoporous composite molecular sieve was prepared by the preparation method of Example 1 of CN106311319A: 1.9 g NaOH and 7.6 g NaAlO2 were added to 295 g TEAOH solution in sequence, and stirred vigorously to mix them evenly. Then 215 g TEOS was slowly added and stirred at room temperature for 4 h. The mixture was transferred to an autoclave and crystallized at 120°C for 24 h to obtain a Beta zeolite seed solution. 2g P123 was added to 80g 1mol / L HCl solution, and then 30g n-butanol was added. After stirring for 4h, 50g TEOS was added, and stirring was continued at 40°C for 2h. Then 80g of the Beta zeolite seed solution prepared above was added, and then 5g La2O3 / PMo heteropolyacid / KIT-6 molecular sieve was added. The mixture was stirred at 40°C for 24h, and then transferred to a self-pressure reactor for crystallization at 100°C for 24h. After filtering, washing, drying and calcining at 550°C, Beta / La2O3 / PMo heteropolyacid / KIT-6 micro-mesoporous composite molecular sieve was finally obtained.

[0106] (3) 15 g of Beta / La2O3 / PMo heteropolyacid / KIT-6 micro-mesoporous composite molecular sieve obtained in step (2), 15 g of Y molecular sieve directing agent, 70 g of aluminum sulfate solution (Al2O3 content of 6 wt%), 40 g of sodium aluminate solution B (Al2O3 content of 15 wt%, Na2O content of 20 wt%) and 2 g of CATB are added to 63 g of water glass solution (SiO2 content of 40 wt%), stirred evenly and then added with 82 g of deionized water to prepare a mixture A, and the mixture A is crystallized at 100° C. for 48 h to obtain a slurry of Y / Beta / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide, and the slurry of Y / Beta / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide is subjected to solid-liquid separation to obtain a solid phase Y / Beta / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide.

[0107] (4) Treat the Y / Beta / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide obtained in step (3) under 800°C water vapor conditions for 0.5 hours.

[0108] (5) The Y / Beta / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide treated with water vapor is 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 a treated molecular sieve composite material.

[0109] (6) The treated molecular sieve composite material is mixed with amorphous phosphorus aluminum, phosphomolybdic acid heteropoly powder, and macroporous alumina binder (based on the total mass after mixing as 100%, the amount of amorphous phosphorus aluminum added is 10wt%, the amount of phosphomolybdic acid heteropoly powder added is 5wt%, and the amount of macroporous alumina binder added is 15wt%), and a hydrocracking catalyst carrier is obtained by kneading, rolling, and extrusion.

[0110] (7) A hydrocracking catalyst carrier is mixed with nano nickel oxide powder and nano tungsten oxide powder, an alumina binder is added, the mixture is rolled and calcined at 580° C. for 2 hours to obtain a hydrocracking catalyst; wherein, based on the total mass of the hydrocracking catalyst carrier, nano nickel oxide powder, nano tungsten oxide powder and alumina binder being 100%, the amount of nano tungsten oxide powder added is 25wt%, the amount of nano nickel oxide powder added is 2wt%, and the amount of alumina binder added is 25wt%.

[0111] Evaluation Example 1

[0112] The specific surface area, pore volume, pore size distribution and infrared acid content of the molecular sieve composite materials provided in Examples 1 to 3 and Comparative Examples 1 to 2 (before being treated with water vapor) were tested, and the results are shown in Table 1.

[0113] Table 1

[0114] sample <![CDATA[Specific surface area (m 2 / g)]]> Pore ​​volume (mL / g) Pore ​​size distribution (nm) Infrared acid content (mmol / g) Example 1 650 0.50 4～15 0.9 Example 2 700 0.60 4～20 1.1 Example 3 780 0.72 4～25 1.4 Comparative Example 1 600 0.40 4～8 0.8 Comparative Example 2 700 0.65 4～20 0.6

[0115] The specific surface area, pore volume and pore size distribution of the hydrocracking catalysts provided in Examples 1 to 3 and Comparative Examples 1 and 2 were tested respectively. The results are shown in Table 2.

[0116] Table 2

[0117] sample <![CDATA[Specific surface area (m 2 / g)]]> Pore ​​volume (mL / g) Pore ​​size distribution (nm) Example 1 350 0.30 4-13 Example 2 400 0.40 4-18 Example 3 480 0.52 4-22 Comparative Example 1 300 0.25 4-8 Comparative Example 2 405 0.45 4-20

[0118] Evaluation Example 2

[0119] The performance of the hydrocracking catalysts provided in Examples 1 to 3 and Comparative Examples 1 to 2 was evaluated using the feedstock oil in Table 3. The reaction conditions and evaluation results are shown in Table 4.

[0120] Table 3 Raw oil properties

[0121]

[0122]

[0123] Table 4 Hydrocracking catalyst reaction performance

[0124] project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Reaction pressure, MPa 12 12 12 12 12 Hydrogen to oil volume ratio 1200 1200 1200 1200 1200 <![CDATA[Air speed, h -1 > 1.2 1.2 1.2 1.2 1.2 Reaction temperature, °C 378 376 374 372 372 Light naphtha yield, wt% 18.1 16.5 15.2 10 13 Heavy naphtha yield, wt% 71.5 69.5 67.5 55 64

[0125] It can be seen from the results in Table 2 and Table 4 that the hydrocracking catalyst prepared by the preparation method of the present invention has improved mesopore pore size distribution, and when used for 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.

[0126] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a hydrocracking catalyst, wherein: The preparation method comprises: The KIT-6 molecular sieve is sprayed with a lanthanum salt-containing phosphomolybdic heteropoly acid complex aqueous solution for adsorption, and then dried and calcined to obtain La2O3 / PMo heteropoly acid / 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: 1Al2O3: (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, organic matter, aluminum source, alkali source, silicon source and water Y molecular sieve directing agent, La2O3 / PMo heteropoly acid / KIT-6 A mesoporous molecular sieve oxide, an organic matter, an aluminum source, an alkali source, a silicon source and water are mixed to obtain a mixture A, the mixture A is crystallized to obtain a slurry of a Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide, and the Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide slurry is subjected to solid-liquid separation to obtain a solid-phase Y / La2O3 / PMo heteropolyacid / KIT-6 molecular sieve composite oxide material, which is the molecular sieve composite material; wherein the organic matter comprises at least one of hydroxypropyl methylcellulose, polyethylene glycol and cetyltrimethylammonium bromide; The molecular sieve composite material is mixed with amorphous aluminum phosphide, phosphomolybdic heteropoly acid, and a macroporous binder to obtain a mixture B, and the mixture B is molded to obtain a catalyst carrier; The catalyst carrier is mixed with the nano metal oxide and the binder to obtain a mixture C, and the mixture C is formed and calcined to obtain a hydrocracking catalyst.

2. The preparation method according to claim 1, wherein During the preparation of La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, the mass of KIT-6 molecular sieve: the mass of lanthanum nitrate: the mass of phosphomolybdic heteropoly acid: the mass of water = 1: (0.01-0.12): (0.1-0.25): (0.5-2); Preferably, the mass of KIT-6 molecular sieve: the mass of lanthanum nitrate: the mass of phosphomolybdic heteropoly acid: the mass of water = 1: (0.05-0.1): (0.15-0.2): (0.5-2).

3. The preparation method according to claim 1, wherein The Y molecular sieve directing agent is prepared by the following method: An alkali source, an aluminum source, a silicon source and water are mixed according to a molar ratio of (6-9)Na2O:1Al2O3:(7-13)SiO2:(200-350)H2O, and a Y molecular sieve directing agent is obtained by aging; Preferably, the aging temperature is 20-60°C; more preferably, the aging temperature is 25-40°C; Preferably, a sodium source, an aluminum source, a silicon source and water are mixed in a molar ratio of (6.5-7.5)Na2O:1Al2O3:(9-11)SiO2:(220-300)H2O, and the Y molecular sieve directing agent is obtained by aging; Preferably, the aluminum source used to prepare the Y molecular sieve directing agent includes at least one of aluminum sulfate and sodium metaaluminate; Preferably, the alkali source used to prepare the Y molecular sieve directing agent includes at least one of sodium metaaluminate and potassium hydroxide; Preferably, the silicon source used to prepare the Y molecular sieve directing agent includes at least one of water glass and silica sol.

4. The preparation method according to claim 1, wherein The preparation method also includes: The solid phase Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material is treated with water vapor before preparing the mixture B; Preferably, the temperature of the water vapor treatment is 500-800°C; more preferably, the temperature of the water vapor treatment is 600-700°C.

5. The preparation method according to claim 4, wherein The preparation method further comprises: treating the Y / La2O3 / PMo heteropoly acid / KIT-6 molecular sieve composite oxide material treated with water vapor with a mixed solution of ammonium sulfate and citric acid, and then using the mixed solution to prepare the mixture B; Preferably, based on 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, based on 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%.

6. The preparation method according to claim 1, wherein Based on the mass of the mixture B being 100%, the addition amount of amorphous aluminum phosphide is 10-20wt%, the addition amount of phosphorus molybdenum heteropoly acid is 1-5wt%, and the addition amount of the macroporous binder is 15-20wt%; Preferably, based on 100% by mass of mixture B, the addition amount of amorphous aluminum phosphide is 15-18wt%, the addition amount of phosphomolybdic heteropoly acid is 2-4wt%, and the addition amount of macroporous binder is 17-18wt%.

7. The preparation method according to claim 1, wherein Nano metal oxides include nano tungsten oxide and nano nickel oxide; Preferably, based on 100% by mass of the mixture C, the addition amount of nano-tungsten oxide is 18-25wt%, and the addition amount of nano-nickel oxide is 2-5wt%; More preferably, based on 100% by mass of the mixture C, the added amount of nano-tungsten oxide is 20-23wt%, and the added amount of nano-nickel oxide is 3-4wt%.

8. The preparation method according to claim 1, wherein Based on 100% of the mass of the mixture C, the added amount of the binder is 20-25wt%.

9. The preparation method according to claim 1, wherein The crystallization temperature is 90-100°C; preferably, the crystallization temperature is 95-100°C; and or During the preparation of La2O3 / PMo heteropoly acid / KIT-6 mesoporous molecular sieve oxide, the calcination temperature is 300-400°C; and or In the process of forming and calcining the mixture C to obtain a hydrocracking catalyst, the calcination temperature is 450-650°C; In the process of obtaining the hydrocracking catalyst by molding and calcining the mixture C, the calcination atmosphere is air atmosphere.

10. The preparation method according to claim 1, wherein: The polyethylene glycol comprises at least one of PEG2000 and PEG200; and / or The lanthanum salt is lanthanum nitrate; and / or The aluminum source used to prepare the mixture A includes at least one of aluminum sulfate and sodium metaaluminate; The alkali source used to prepare the mixture A comprises at least one of sodium metaaluminate and potassium hydroxide; and / or The silicon source used to prepare the mixture A comprises at least one of water glass and silica sol; and / or The macroporous binder used to prepare the mixture B is a macroporous alumina binder; and / or The binder used to prepare the mixture C is an alumina binder.

11. The hydrocracking catalyst prepared by the method for preparing the hydrocracking catalyst according to any one of claims 1 to 10; Preferably, the specific surface area of ​​the hydrocracking catalyst is 350-400m 2 / g, the total pore volume is 0.3-0.52mL / g, and the pore size distribution is 4-22nm.

12. Use of the hydrocracking catalyst according to claim 11 in the preparation of light naphtha and heavy naphtha by hydrocracking of aromatic fraction oil.

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