Precious metal-transition metal-molecular sieve catalyst and preparation method thereof

Abstract

The invention provides a noble metal-transition metal-molecular sieve catalyst, a preparation method and application, and belongs to the field of environmental protection, a carrier of the catalyst is an SSZ-13 molecular sieve, and active components comprise noble metal, transition metal oxide and noble metal and transition metal alloy; the catalyst is synthesized in situ by adopting a one-pot method by taking a noble metal source, a transition metal source, triethylamine (TEA), a template agent, a silicon source, an aluminum source and sodium hydroxide as raw materials according to a certain proportion; the catalyst prepared by the method has excellent low-temperature activity, excellent hydrothermal stability and excellent sulfur poisoning resistance, and can adapt to complex working conditions in an ammonia-diesel dual-fuel engine tail gas aftertreatment system; the catalyst can be used for removing nitrogen oxides (NOx) and high-concentration escape ammonia (NH3) at the same time in an ammonia-diesel dual-fuel engine tail gas after-treatment system so as to achieve the purpose of purifying tail gas.

Description

Technical Field

[0001] The present invention relates to the field of environmental protection catalysts, and particularly to a noble metal-transition metal-zeolite catalyst and a preparation method thereof. Background Art

[0002] With the increasing shortage of energy resources and environmental protection issues, finding alternative clean fuels has become an urgent task. Currently, for the shipping industry, using ammonia as a marine fuel can significantly reduce ship carbon emissions. However, there are nitrogen oxides and high concentrations of escaped ammonia in the exhaust gas of marine ammonia-diesel dual-fuel engines, which will greatly limit the large-scale application of ammonia-diesel dual-fuel engines in the shipping field in the future. For traditional marine diesel engine exhaust gas to reduce nitrogen oxides and ammonia emissions, an SCR system and an ASC system are used in series for post-treatment of exhaust gas, but there are disadvantages such as a large amount of catalyst used, high cost, and large volume. Currently, both domestic and foreign are developing technologies for exhaust gas pollutants applicable to ammonia-diesel dual-fuel engines, but no mature and available catalyst products have been introduced. Therefore, there is an urgent need to develop a dual-functional catalyst with the ability to simultaneously denitrate and deammoniate to ensure that ammonia-diesel dual-fuel engines can meet international and regional emission standards, reduce potential legal and compliance risks, and thus promote the green transformation of the global shipping industry. Summary of the Invention

[0003] In view of the above-mentioned defects of the prior art, the technical solution of the present invention provides a noble metal-transition metal / zeolite catalyst and a preparation method thereof to solve the technical problems existing in the above-mentioned background art.

[0004] To achieve the above object, the present invention provides a noble metal-transition metal-zeolite catalyst, which is characterized in that it includes a carrier and active components, wherein the carrier is SSZ-13 zeolite; the active components include noble metals, transition metal oxides, and alloys of noble metals and transition metals;

[0005] The content of the noble metal is 0.1-1% of the total weight of the zeolite, and the content of the transition metal oxide is 0.1-5% of the total weight of the zeolite.

[0006] Preferably, the noble metal is platinum, ruthenium, palladium, or rhodium.

[0007] Preferably, the transition metal is copper, and the transition metal oxide is copper oxide.

[0008] Preferably, in the copper oxide, Cu 2+ accounts for 80% or more of the total copper content.

[0009] On the other hand, the present invention provides a preparation method of a noble metal-transition metal-zeolite catalyst, including the following steps:

[0010] (1) At room temperature, completely dissolve the noble metal source and the transition metal source in water, and add TEA to form a noble metal-transition metal-TEA complex solution;

[0011] (2) Add sodium hydroxide, aluminum source, template agent, and silicon source to the obtained solution in sequence, and stir evenly after mixing to obtain a precursor gel;

[0012] (3) Pour the precursor gel into a crystallization kettle for crystallization;

[0013] (4) Cool the crystallization product, remove the mother liquor, wash it with deionized water until neutral, and dry to obtain the catalyst raw powder;

[0014] (5) Calcinate the catalyst raw powder in a muffle furnace to obtain a noble metal-transition metal / molecular sieve catalyst.

[0015] Preferably, the aluminum source is one or more of sodium metaaluminate, pseudoboehmite, aluminum hydroxide, or aluminum isopropoxide;

[0016] The silicon source is one or more of silica sol, nano-silica powder, or tetraethyl orthosilicate;

[0017] The noble metal source is one or more of platinum nitrate, ruthenium nitrosyl nitrate, palladium nitrate, or rhodium nitrate;

[0018] The transition metal source is one or more of copper nitrate trihydrate, copper sulfate pentahydrate;

[0019] The template agent is one or more of 1-adamantyltrimethylammonium hydroxide, diaminomethylpyridine, diaminopropane, or p-butylcyclohexanecarboxylic acid.

[0020] Preferably, before preparing the precursor gel in steps (1) and (2), the molar ratios of various substances in the synthesis system are:

[0021] SiO2 / Al2O3 = 10 - 100;

[0022] SiO2 / noble metal = 2000 - 10000;

[0023] SiO2 / transition metal = 50 - 200;

[0024] Na2O / SiO2 = 0.1 - 0.5;

[0025] H2O / SiO2 = 10 - 50;

[0026] Template agent / SiO2 = 0.1 - 0.5.

[0027] Preferably, in step (1), the specific process for preparing the noble metal-transition metal-TEA complex is as follows: Weigh the required amounts of the noble metal source and the transition metal source according to the calculated amounts of the drugs. First, dissolve the noble metal source and the transition metal source in deionized water, stir for 5-10 minutes at a temperature of 20-40 °C to obtain a clear solution, and then add triethylamine and stir for 30-60 minutes at a temperature of 20-40 °C to obtain a noble metal-transition metal-TEA complex solution.

[0028] Preferably, in step (2), the specific process for preparing the precursor gel is as follows: Weigh sodium hydroxide, an aluminum source, and a template agent according to the calculated amounts of the drugs, add them to the solution obtained in step (1), stir for 30 minutes at a temperature of 20-40 °C, and then slowly add a silicon source to the solution and stir for 1-2 hours at a temperature of 20-40 °C to obtain a precursor gel.

[0029] Preferably, in step (3), the specific process for crystallization is as follows: Pour the fully stirred precursor gel into a 100 ml hydrothermal reaction kettle with a polytetrafluoroethylene liner and place it in an oven at 160-190 °C for crystallization for 2-6 days;

[0030] Preferably, in step (4), the process for obtaining the catalyst raw powder is as follows: Filter the crystallized product to remove the mother liquor, wash it with deionized water until it is neutral, and finally place it in an oven at 100-120 °C for drying for 10-12 hours to obtain the catalyst raw powder.

[0031] Preferably, it is characterized in that in step (5), place the catalyst raw powder in a muffle furnace, raise the temperature to 500-600 °C at a heating rate of 6 °C / min, maintain it at this temperature for 4-6 hours, and after cooling to room temperature, obtain the noble metal-transition metal / molecular sieve catalyst.

[0032] On the other hand, the present invention provides an application of a noble metal-transition metal-molecular sieve catalyst in simultaneous denitrification and deammoniation of the exhaust gas of a marine ammonia-diesel dual-fuel engine.

[0033] The beneficial technical effects of the present invention:

[0034] (1) The raw materials used in the present invention for preparing the catalyst are easily available, and the process for preparing the catalyst is simple, overcoming the disadvantages of the traditional impregnation method and ion exchange preparation method, such as cumbersome steps and high costs.

[0035] (2) The catalyst prepared by the present invention has good activity in a wide temperature range of 230 °C to 450 °C and can achieve efficient and stable denitrification and deammoniation.

[0036] (3) The noble metal-transition metal / molecular sieve catalyst in-situ synthesized by the one-pot method in the present invention overcomes the disadvantages of the traditional SCR+ASC post-treatment system for marine diesel engines, making it particularly suitable for the post-treatment of the exhaust gas of marine ammonia-diesel dual-fuel engines.

[0037] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the drawings to fully understand the purpose, features and effects of the present invention. Brief Description of the Drawings

[0038] Figure 1 is the preparation flow chart of the noble metal-transition metal-molecular sieve catalyst;

[0039] Figure 2 is the graph of the change of the conversion rate of nitrogen oxides with temperature in the simultaneous denitrification and deammoniation reactions of each noble metal-transition metal-molecular sieve catalyst;

[0040] Figure 3 is the graph of the change of the ammonia conversion rate with temperature in the simultaneous denitrification and deammoniation reactions of each noble metal-transition metal-molecular sieve catalyst;

[0041] Figure 4 is the graph of the change of the nitrogen selectivity with temperature in the simultaneous denitrification and deammoniation reactions of each noble metal-transition metal-molecular sieve catalyst. Detailed Embodiments

[0042] The following introduces multiple preferred embodiments of the present invention with reference to the drawings of the specification to make its technical content clearer and easier to understand. The present invention can be embodied in many different forms of embodiments, and the protection scope of the present invention is not limited to the embodiments mentioned in the text.

[0043] In the drawings, components with the same structure are denoted by the same numerical labels, and components with similar structures or functions are denoted by similar numerical labels. The size and thickness of each component shown in the drawings are arbitrarily shown, and the present invention does not limit the size and thickness of each component. To make the drawings clearer, the thickness of some parts in the drawings is appropriately exaggerated.

[0044] The present invention provides a noble metal-transition metal-molecular sieve catalyst, including a carrier and an active component, wherein the carrier is an SSZ-13 molecular sieve; the active component includes a noble metal, a transition metal oxide and an alloy of the noble metal and the transition metal;

[0045] The SSZ-13 molecular sieve is a microporous silica-aluminate material with a CHA-type framework structure, with its high specific surface area (550-700m 2 / g), excellent thermal / hydrothermal stability and adjustable acidic sites are the core advantages. Its synthesis is achieved through a multilevel pore design strategy assisted by amphiphilic organosilanes or long-chain diquaternary ammonium salts, or a low-cost process based on kaolin, forming a highly crystalline structure with both micropores and mesopores.

[0046] The content of the noble metal is 0.1-1% of the total weight of the molecular sieve, and it is evenly distributed on the surface of the molecular sieve; the content of the transition metal oxide is 0.1-5% of the total weight of the molecular sieve; and it is evenly distributed on the inner surface of the molecular sieve.

[0047] The noble metal is platinum, ruthenium, palladium or rhodium; the transition metal is copper, the transition metal oxide is copper oxide, and in the copper oxide, Cu 2+ accounts for 80% or more of the total copper content.

[0048] As Figure 1 shown, on the other hand, the present invention provides a method for preparing a noble metal-transition metal-molecular sieve catalyst, comprising the following steps:

[0049] (1) Prepare a noble metal-transition metal-TEA complex solution

[0050] At room temperature, dissolve the noble metal source and the transition metal source completely in water, and add TEA to form a noble metal-transition metal-TEA complex solution;

[0051] Specifically: Weigh the required amounts of the noble metal source and the transition metal source according to the calculated amounts of the drugs; first dissolve the noble metal source and the transition metal source in deionized water, stir for 5-10 minutes at a temperature of 20-40 °C to obtain a clear solution, and then add triethylamine and stir for 30-60 minutes at a temperature of 20-40 °C to obtain a noble metal-transition metal-TEA complex solution.

[0052] (2) Prepare a precursor gel

[0053] Add sodium hydroxide, an aluminum source, a template agent, and a silicon source to the obtained solution in sequence, and stir evenly after mixing to obtain a precursor gel;

[0054] Specifically: Weigh sodium hydroxide, an aluminum source, and a template agent according to the calculated amounts of the drugs and add them to the solution obtained in step (1), stir for 30 minutes at a temperature of 20-40 °C, and then slowly add the silicon source to the solution and stir for 1-2 hours at a temperature of 20-40 °C to obtain a precursor gel.

[0055] (3) Crystallization

[0056] Pour the precursor gel into a crystallization kettle for crystallization;

[0057] Specifically: Pour the completely stirred precursor gel into a 100 ml hydrothermal reactor with a polytetrafluoroethylene liner, and place it in an oven at 160 - 190 °C for crystallization for 2 - 6 days;

[0058] (4) Washing and drying

[0059] Cool the crystallization product, remove the mother liquor, wash it with deionized water until neutral, and dry to obtain the catalyst raw powder;

[0060] Specifically: Remove the mother liquor from the crystallization product by filtration, wash it with deionized water until neutral, and finally place it in an oven at 100 - 120 °C for drying for 10 - 12 h to obtain the catalyst raw powder.

[0061] (5) Calcination

[0062] Place the catalyst raw powder in a muffle furnace for calcination to obtain the noble metal-transition metal / molecular sieve catalyst.

[0063] Specifically: Place the catalyst raw powder in a muffle furnace, heat it to 500 - 600 °C at a heating rate of 6 °C / min, hold it at this temperature for 4 - 6 h, and obtain the noble metal-transition metal / molecular sieve catalyst after cooling to room temperature.

[0064] The aluminum source is one or more of sodium aluminate, pseudoboehmite, aluminum hydroxide, or aluminum isopropoxide;

[0065] The silicon source is one or more of silica sol, silicon dioxide nanopowder, or tetraethyl orthosilicate;

[0066] The noble metal source is one or more of platinum nitrate, ruthenium nitrosyl nitrate, palladium nitrate, or rhodium nitrate;

[0067] The transition metal source is one or more of copper nitrate trihydrate, copper sulfate pentahydrate;

[0068] The template agent is one or more of 1-adamantyltrimethylammonium hydroxide, diaminomethylpyridine, diaminopropane, or p-butylcyclohexanecarboxylic acid.

[0069] Before preparing the precursor gel in steps (1) and (2), the molar ratios of the substances in the synthesis system are:

[0070] SiO2 / Al2O3 = 10 - 100;

[0071] SiO2 / noble metal = 2000 - 10000;

[0072] SiO2 / transition metal = 50 - 200;

[0073] Na2O / SiO2 = 0.1 - 0.5;

[0074] H2O / SiO2 = 10 - 50;

[0075] Template agent / SiO2 = 0.1 - 0.5.

[0076] The present invention will be further described below in conjunction with specific embodiments.

[0077] Example 1

[0078] Accurately weigh 0.054lg of platinum nitrate (Pt(NO3)2) solution with a Pt content of 18.02% and 0.2416g of copper nitrate trihydrate, add them to deionized water, stir (400r / min) at 25°C for 5min to obtain a clear solution. Add 7.5g of triethylamine (TEA) to the clear solution, stir (400r / min) at 25°C for 30min to obtain a Pt-Cu-TEA complex. Secondly, accurately weigh 0.8g of sodium hydroxide, 0.41g of sodium aluminate, and 6.3405g of 1-adamantyltrimethylammonium hydroxide and add them to the above solution in sequence, stir (400r / min) at 25°C for 30min, then slowly add 15g of silica sol, stir (400r / min) at 25°C for 1h to obtain a Pt-Cu precursor gel. Load the precursor gel into a 100ml hydrothermal reaction kettle with a polytetrafluoroethylene liner and crystallize it in an oven at 160°C for 3 days. After crystallization, filter to remove the mother liquor, wash with deionized water until neutral, and place the obtained solid in an oven at 100°C to dry for 12h to obtain the Pt-Cu catalyst raw powder. Finally, grind the Pt-Cu catalyst raw powder into powder and place it in a muffle furnace for calcination, raise the temperature to 550°C at a heating rate of 6°C / min, and hold at this temperature for 5h. The obtained catalyst is denoted as the Pt-Cu supported molecular sieve catalyst.

[0079] Example 2

[0080] Accurately weigh 0.3369 g of ruthenium nitrosyl nitrate (Pt(NO)(NO3)3) solution with a Ru content of 1.5%, and 0.2416 g of copper nitrate trihydrate, add them to deionized water, stir (400 r / min) at 25 °C for 5 min to obtain a clear solution. Add 7.5 g of triethylamine (TEA) to the clear solution, stir (400 r / min) at 25 °C for 30 min to obtain a Ru-Cu-TEA complex. Secondly, accurately weigh 0.8 g of sodium hydroxide, 0.41 g of sodium aluminate, and 6.3405 g of 1-adamantyltrimethylammonium hydroxide, and add them to the above solution in sequence. Stir (400 r / min) at 25 °C for 30 min, then slowly add 15 g of silica sol, and stir (400 r / min) at 25 °C for 1 h to obtain a Ru-Cu precursor gel. Load the precursor gel into a 100 ml hydrothermal reaction kettle with a polytetrafluoroethylene lining, and crystallize in an oven at 160 °C for 3 days. After crystallization, filter to remove the mother liquor, wash with deionized water until neutral, and place the obtained solid in an oven at 100 °C to dry for 12 h to obtain the original Ru-Cu catalyst powder. Finally, grind the original Ru-Cu catalyst powder into powder and place it in a muffle furnace for calcination. Raise the temperature to 550 °C at a heating rate of 6 °C / min and maintain at this temperature for 5 h. The obtained catalyst is denoted as Ru-Cu supported molecular sieve catalyst.

[0081] Example 3

[0082] Accurately weigh 0.1330 g of palladium nitrate (Pd(NO3)2) solution with a Pd content of 4-5%, and 0.2416 g of copper nitrate trihydrate, add them to deionized water, stir (400 r / min) at 25 °C for 5 min to obtain a clear solution. Add 7.5 g of triethylamine (TEA) to the clear solution, stir (400 r / min) at 25 °C for 30 min to obtain a Pd-Cu-TEA complex. Secondly, accurately weigh 0.8 g of sodium hydroxide, 0.41 g of sodium aluminate, and 6.3405 g of 1-adamantyltrimethylammonium hydroxide, and add them to the above solution in sequence. Stir (400 r / min) at 25 °C for 30 min, then slowly add 15 g of silica sol, and stir (400 r / min) at 25 °C for 1 h to obtain a Pd-Cu precursor gel. Load the precursor gel into a 100 ml hydrothermal reaction kettle with a polytetrafluoroethylene lining, and crystallize in an oven at 160 °C for 3 days. After crystallization, filter to remove the mother liquor, wash with deionized water until neutral, and place the obtained solid in an oven at 100 °C to dry for 12 h to obtain the original Pd-Cu catalyst powder. Finally, grind the original Pd-Cu catalyst powder into powder and place it in a muffle furnace for calcination. Raise the temperature to 550 °C at a heating rate of 6 °C / min and maintain at this temperature for 5 h. The obtained catalyst is denoted as Pd-Cu supported molecular sieve catalyst.

[0083] Example 4

[0084] Accurately weigh 0.0515 g of rhodium nitrate (Rh(NO3)3) solution with 10% Rh content and 0.2416 g of copper nitrate trihydrate, add them to deionized water, stir (400 r / min) at 25 °C for 5 min to obtain a clear solution. Add 7.5 g of triethylamine (TEA) to the clear solution, stir (400 r / min) at 25 °C for 30 min to obtain a Rh-Cu-TEA complex. Secondly, accurately weigh 0.8 g of sodium hydroxide, 0.41 g of sodium aluminate, and 6.3405 g of 1-adamantyltrimethylammonium hydroxide and add them to the above solution in sequence, stir (400 r / min) at 25 °C for 30 min, then slowly add 15 g of silica sol, stir (400 r / min) at 25 °C for 1 h to obtain a Rh-Cu precursor gel. Load the precursor gel into a 100 ml hydrothermal reaction kettle with a polytetrafluoroethylene liner and crystallize it in an oven at 160 °C for 3 days. After crystallization, filter to remove the mother liquor, wash with deionized water until neutral, and place the obtained solid in an oven at 100 °C and dry for 12 h to obtain the original Rh-Cu catalyst powder. Finally, grind the original Rh-Cu catalyst powder into powder and place it in a muffle furnace for calcination, raise the temperature to 550 °C at a heating rate of 6 °C / min, and hold at this temperature for 5 h. The obtained catalyst is denoted as the Rh-Cu supported molecular sieve catalyst.

[0085] Application example

[0086] Apply the prepared Pt-Cu / SSZ-13, Ru-Cu / SSZ-13, Pd-Cu / SSZ-13, Rh-Cu / SSZ-13 catalysts to the simultaneous denitrification and deammoniation reaction. The specific reaction conditions are as follows: This reaction test is carried out in a fixed-bed continuous-flow quartz reactor. The catalyst particle size is 40 - 60 mesh and the dosage is 0.2 ml. The reaction gas composition is 5000 ppm NH3, 1000 ppm NO, 10 vol% O2, N2 carrier gas, the gas flow rate is 200 ml / min, and the space velocity is 60,000 h -1 , and the reaction temperature range of the catalyst is 150 - 450 °C. The products are detected and analyzed by a Fourier transform infrared flue gas analyzer (Intari s IGS), and NO x conversion rate, NH3 conversion rate, and N2 selectivity are calculated by the following formulas:

[0087]

[0088] Among them, [NO x in represents the initial concentration of NO x , [NO x out represents NO at the outlet of the flue gas analyzer​​x Concentration, [NH3] in Represents the initial concentration of NH3, [NH3] out Represents the NH3 concentration at the outlet of the flue gas analyzer, [N2O] out Represents the generated concentration of N2O.

[0089] To evaluate the simultaneous denitrification and deammoniation performance of noble metal-transition metal-zeolite catalysts, activity reaction tests were carried out on 4 specific examples that had been successfully prepared. The specific reaction conditions are as follows: The activity test was carried out in a fixed-bed continuous-flow quartz reactor. The catalyst particle size was 40 - 60 mesh, and the dosage was 0.2 ml. The reaction gas composition was 5000 ppm NH3, 1000 ppm NO, 10 vol% O2, with N2 as the carrier gas, the gas flow rate was 200 ml / min, and the space velocity was 60,000 h -1 , and the reaction temperature range of the catalyst was 150 - 450 °C.

[0090] Figure 2 It is a graph showing the change of NOx conversion rate with temperature in the simultaneous denitrification and deammoniation reaction of each noble metal-transition metal-zeolite catalyst; Figure 3 It is a graph showing the change of ammonia conversion rate with temperature in the simultaneous denitrification and deammoniation reaction of each noble metal-transition metal-zeolite catalyst; Figure 4 It is a graph showing the change of nitrogen selectivity with temperature in the simultaneous denitrification and deammoniation reaction of each noble metal-transition metal-zeolite catalyst. These three figures are the activity result graphs of the tests on the four previous examples. From the above activity results, it can be seen that the noble metal-transition metal-zeolite catalyst synthesized in the present invention has excellent simultaneous denitrification and deammoniation ability. Among the 4 specific examples that have been successfully prepared, the Pd-Cu / SSZ-13 catalyst has the best effect.

[0091] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations according to the concept of the present invention without creative labor. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should be within the protection scope determined by the claims.

Claims

1. A noble metal-transition metal-zeolite catalyst, characterized in that, It includes a carrier and an active component. Among them, the carrier is SSZ-13 molecular sieve; the active component includes noble metals, transition metal oxides and alloys of noble metals and transition metals; The content of the noble metal is 0.1-1% of the total weight of the molecular sieve, and the content of the transition metal oxide is 0.1-5% of the total weight of the molecular sieve.

2. The noble metal-transition metal-zeolite catalyst according to claim 1, wherein The noble metal is platinum, ruthenium, palladium or rhodium.

3. The noble metal-transition metal-zeolite catalyst according to claim 1, wherein The transition metal is copper, and the transition metal oxide is copper oxide.

4. The noble metal-transition metal-zeolite catalyst according to claim 3, wherein In the copper oxide, Cu 2+ accounts for 80% or more of the total copper content.

5. A method for preparing a noble metal-transition metal-zeolite catalyst, characterized in that, It includes the following steps: (1) At room temperature, completely dissolve the noble metal source and the transition metal source in water, and add TEA to form a noble metal-transition metal-TEA complex solution; (2) Sequentially add sodium hydroxide, aluminum source, template agent, and silicon source to the obtained solution, mix and stir evenly to obtain a precursor gel; (3) Pour the precursor gel into a crystallization kettle for crystallization; (4) Cool the crystallization product, remove the mother liquor, wash it with deionized water until neutral, and dry to obtain the catalyst raw powder; (5) Roast the catalyst raw powder in a muffle furnace to obtain the noble metal-transition metal / molecular sieve catalyst.

6. According to the preparation method described in claim 5, characterized in that The aluminum source is one or more of sodium metaaluminate, pseudo-boehmite, aluminum hydroxide or aluminum isopropoxide; The silicon source is one or more of silica sol, silica nanopowder or tetraethyl orthosilicate; The noble metal source is one or more of platinum nitrate, ruthenium nitrosyl nitrate, palladium nitrate or rhodium nitrate; The transition metal source is one or more of copper nitrate trihydrate, copper sulfate pentahydrate; The template agent is one or more of 1-adamantyltrimethylammonium hydroxide, diaminomethylpyridine, diaminopropane or p-butylcyclohexanecarboxylic acid.

7. The preparation method according to claim 5, characterized in that, Before preparing the precursor gel in steps (1) and (2), the molar ratios of various substances in the synthesis system are: SiO2 / A12O3 = 10-100; SiO2 / noble metal = 2000-10000; SiO2 / transition metal = 50-200; Na2O / SiO2 = 0.1-0.5; H2O / SiO2 = 10-50; template agent / SiO2 = 0.1-0.

5.

8. The preparation method according to claim 5, characterized in that, In step (1), the specific process of preparing the noble metal-transition metal-TEA complex is to weigh the required amounts of the noble metal source and the transition metal source according to the calculated amounts of the drugs; first dissolve the noble metal source and the transition metal source in deionized water, stir at a temperature of 20-40 °C for 5-10 min to obtain a clear solution, and then add triethylamine and stir at a temperature of 20-40 °C for 30-60 min to obtain the noble metal-transition metal-TEA complex solution.

9. The preparation method according to claim 5, characterized in that In step (2), the specific process of preparing the precursor gel is to weigh sodium hydroxide, aluminum source, and template agent according to the calculated amounts of the drugs and add them to the solution obtained in step (1), stir at a temperature of 20-40 °C for 30 min, and then slowly add the silicon source to the solution and stir at a temperature of 20-40 °C for 1-2 h to obtain the precursor gel.

10. The preparation method according to claim 5, characterized in that, In step (3), the specific crystallization process is as follows: pour the fully stirred precursor gel into a 100 ml hydrothermal reactor with a polytetrafluoroethylene liner, and place it in an oven at 160 - 190 °C for crystallization for 2 - 6 days.

11. The preparation method according to claim 5, characterized in that In step (4), the process of obtaining the catalyst raw powder is as follows: filter the crystallized product to remove the mother liquor, wash it with deionized water until neutral, and finally place it in an oven at 100 - 120 °C for drying for 10 - 12 h to obtain the catalyst raw powder.

12. The preparation method according to claim 5, characterized in that, In step (5), place the catalyst raw powder in a muffle furnace, heat it to 500 - 600 °C at a heating rate of 6 °C / min, maintain it at this temperature for 4 - 6 h, and after cooling to room temperature, obtain the noble metal-transition metal / molecular sieve catalyst.

13. The noble metal-transition metal-molecular sieve catalyst according to any one of claims 1 - 4 or The application of the noble metal-transition metal-molecular sieve catalyst prepared by the preparation method according to any one of claims 5 - 12 in the simultaneous denitrification and deammoniation of the exhaust gas of a marine ammonia-diesel dual-fuel engine.

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