Double-layer coated metal particle catalyst, preparation method and application in catalytic synthesis of pentamethylenediamine

Abstract

This invention discloses a double-layer-coated metal particle catalyst, its preparation method, and its application in the catalytic synthesis of pentanediamine. Transition metal nanoparticles are the active sites for decarboxylation reactions. Using them as the core of the catalyst, firstly, the rich pore structure of a molecular sieve is utilized to confine the metal nanoparticles, resulting in highly dispersed metal nanoparticles with a size of ~1.5 nm, preventing agglomeration during the reaction. Secondly, an acid-resistant silicon shell is grown in situ on the outer layer of the molecular sieve using a hydrothermal synthesis crystallization method to prevent corrosion from inorganic acids in the reaction solution. Compared with single-layer-coated catalysts, the double-layer-coated catalyst of this invention significantly improves the catalyst's stability. After 5 cycles, the lysine conversion rate reaches 80%, and the pentanediamine selectivity is 60%. This invention provides a new industrialization opportunity for the chemical decarboxylation of lysine to produce pentanediamine and has promising industrial application prospects.

Description

Technical Field

[0001] This invention relates to the field of chemical synthesis, specifically to a double-layered metal particle catalyst, its preparation method, and its application in the catalytic synthesis of pentanediamine. Background Technology

[0002] 1,5-Pentanediamine, also known as cadaverine, can be polymerized with adipic acid to produce nylon 56. Nylon 56 possesses excellent comprehensive properties, such as high moisture wicking capacity, good breathability, softness, and excellent dyeing performance. It is also wear-resistant, chemically resistant, flame-retardant, and easy to process, giving it a strong competitive advantage among nylon materials. The most reported production method for 1,5-pentanediamine is bio-fermentation. Nanjing University of Technology has used soybean residue hydrolysate for fermentation to produce pentanediamine (CN201810954086.X). However, pentanediamine is toxic to microorganisms, affecting production efficiency. Shanghai Kaisai Biotechnology R&D Center Co., Ltd. has applied for several patents on pentanediamine bio-fermentation methods (CN201811506539.9, CN201710453415.8, CN201710011198.7, etc.). The patents indicate that inoculating the seed culture of a lysine decarboxylase strain during lysine fermentation effectively improves the toxicity of pentanediamine to the strain. However, bio-fermentation still faces significant challenges, such as low lysine decarboxylase activity, poor toxicity resistance, low product concentration, and high separation costs.

[0003] Compared to bio-fermentation decarboxylation, chemical decarboxylation has significant advantages, such as catalyst activity not being affected by pentanediamine toxicity and easy product separation. However, currently reported chemical methods for preparing pentanediamine have two main problems: the low rate of monopentanediamine formation, mainly due to low catalyst performance; and the fact that currently reported catalysts for the decarboxylation of lysine to pentanediamine are mainly supported ruthenium catalysts. In 2017, the use of Ru / C as a catalyst for the decarboxylation of L-lysine was first reported, with a pentanediamine selectivity of 32%.

[0004] Chinese patent application number 202110938327.3 discloses a molecular sieve-confined metal oxide catalyst, its preparation method, and its application. This invention uses an in-situ synthesis method to prepare a molecular sieve-confined metal catalyst. The active metal component of this catalyst is effectively immobilized, preventing agglomeration and maintaining a good catalyst structure. Using the catalyst in the lysine decarboxylation reaction effectively increases the production rate of pentanediamine and shortens the reaction time, but the selectivity needs further improvement.

[0005] Chinese patent application No. 202211265811.5 discloses a method for synthesizing pentanediamine using metal ion-modified molecular sieve-confined transition metal nanoparticles and their catalytic action. By altering the catalyst surface alkalinity, the method promotes the directional adsorption of carboxyl groups, thereby suppressing byproduct generation, improving selectivity, and achieving efficient pentanediamine synthesis. Specifically, by changing the catalyst surface alkalinity, the method effectively enhances the directional adsorption of lysine carboxyl groups, suppressing side reactions at the source and strengthening the direct decarboxylation of lysine to pentanediamine, significantly improving the selectivity. The selectivity for pentanediamine synthesis using metal ion-modified molecular sieve-confined transition metal nanoparticles as a catalyst reaches 77.4%, currently at an internationally leading level. However, the poor catalyst stability remains the biggest challenge restricting industrial production of the lysine decarboxylation reaction, which occurs under high temperature, high pressure, and acidic conditions. For example, in traditional Ru / C catalysts, carbon undergoes methanation, causing catalyst structure collapse and deactivation. Catalysts supported by molecular sieves also exhibit deactivation after reaction. The aluminum in the molecular sieve detaches, causing the molecular sieve structure to collapse. Therefore, it is extremely important to prepare catalysts that combine selectivity and stability for pentanediamine decarboxylation.

[0006] In view of this, the present invention is hereby proposed. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides a double-layer coated metal particle catalyst and its preparation method, and uses the catalyst to prepare pentanediamine from lysine via chemical decarboxylation. The catalyst exhibits high pentanediamine selectivity in the lysine decarboxylation reaction, while also demonstrating good stability and promising prospects for industrial application.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0009] A method for preparing a double-layer encapsulated metal particle catalyst and its catalytic synthesis of pentanediamine is disclosed. The method for preparing the double-layer encapsulated metal particle catalyst involves confining and encapsulating metal nanoparticles (M) with the abundant pore structure of a molecular sieve (ZEO) to form M@ZEO; then adding a directing agent and a silicon source for a second encapsulation; after crystallization at a certain temperature and time, washing and drying, and calcination, a double-layer encapsulated catalyst with metal nanoparticles as the core is formed.

[0010] In a preferred embodiment, the M@ZEO includes any one of Ru@MFI, Ru@GIS, Ru@FAU, and Ru@LTA, and the mass fraction of the M@ZEO, i.e., the catalyst encapsulated by metal particles, is 1 to 80% in the catalyst.

[0011] In a preferred embodiment, the structure directing agent is one or more of tetrapropylammonium hydroxide, sodium hydroxide, and BMP.

[0012] In a preferred embodiment, after adding a structure-directing agent, water, a silicon source, and a catalyst encapsulated in metal particles, the mixture is stirred at room temperature for 1-20 hours at a stirring rate of 50-1000 rpm. After stirring, the mixture is placed in a reaction vessel, and the crystallization reaction is carried out for 5-72 hours after the temperature rises to 80-350°C. Preferably, the stirring time is 2-10 hours, the crystallization temperature is 100-300°C, and the crystallization time is 12-48 hours.

[0013] In a preferred embodiment, the mass ratio of M@ZEO, the directing agent, and the silicon source is 1:1:1 to 1:10:10.

[0014] In a preferred embodiment, the calcination temperature is 300-600℃ and the calcination time is 2-8h.

[0015] The present invention provides a double-layer coated metal particle catalyst for the catalytic synthesis of pentanediamine. The method is as follows: lysine or lysine salt, water and catalyst are placed in a high-pressure reactor and reacted to obtain an aqueous solution containing pentanediamine.

[0016] In a preferred embodiment, the lysine is L-lysine, and the lysine salt is any one of lysine hydrochloride, lysine sulfate, lysine acetate, and lysine phosphate.

[0017] In a preferred embodiment, the molar ratio of the catalyst to lysine or lysine salt is 1:(0.1~10).

[0018] In a preferred embodiment, the reaction conditions of the autoclave are: reaction temperature 120~250℃, pressure 1~3MPa, lysine or lysine salt concentration 0.01~3 M, pH value of lysine or lysine salt solution 1~5, reaction time 0~600 min, and reaction atmosphere any one of nitrogen, hydrogen, argon, helium or carbon monoxide.

[0019] Compared to existing technologies, the advantages of this invention are as follows: This invention provides a double-layer-coated metal particle catalyst. Transition metal nanoparticles are the active sites for the decarboxylation reaction, serving as the core of the catalyst. First, the rich pore structure of a molecular sieve confines the metal nanoparticles, resulting in highly dispersed metal nanoparticles with a size of ~1.5 nm, preventing agglomeration during the reaction. Second, a hydrothermal synthesis crystallization method is used to grow an acid-resistant silicon shell in situ on the outer layer of the molecular sieve, preventing corrosion from inorganic acids in the reaction solution. This invention significantly improves the stability of the catalyst. When used in the chemical decarboxylation of lysine to prepare pentanediamine, this double-layer-coated metal particle catalyst exhibits high selectivity for pentanediamine in the lysine decarboxylation reaction, while also demonstrating good stability and promising industrial application prospects. Attached Figure Description

[0020] Figure 1 XRD patterns of the catalysts in Examples 1-3 and Comparative Example 1;

[0021] Figure 2 XRD patterns of the catalyst before and after the reaction in Example 1;

[0022] Figure 3 XRD patterns of the catalyst before and after the reaction in Example 2;

[0023] Figure 4 XRD patterns of the catalyst before and after the reaction in Example 3;

[0024] Figure 5 XRD patterns of the catalyst before and after the reaction in Comparative Example 1. Detailed Implementation

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1

[0027] The synthesis method of the double-layer-coated metal particle catalyst in this embodiment is as follows:

[0028] (1) Synthesis of Ru@FAU: 2.8 g of sodium hydroxide was dissolved in 25 ml of deionized water and stirred until clear. 0.3375 g of sodium aluminate was added and stirred until clear. 12.68 g of silica sol was slowly added dropwise. After the addition was complete, 0.34 g of ruthenium chloride was added and stirred at 600 rpm for 4 h at room temperature. The resulting solution was transferred to a stainless steel hydrothermal synthesis vessel and crystallized at 100 °C for 12 h. After the hydrothermal synthesis vessel was completely cooled, it was washed with deionized water until the pH of the filtrate was neutral. The solution was dried overnight at 100 °C to obtain the Ru@FAU catalyst.

[0029] (2) Mix 5.084 g of tetrapropylammonium hydroxide with 39.2 g of deionized water and stir the solution until uniform. During the stirring process, slowly add 1 g of Ru@FAU catalyst and then add 5.208 g of tetraethyl orthosilicate to the above solution. Stir magnetically for 6 h at room temperature. The solution obtained after stirring is placed in a stainless steel high-pressure reactor and crystallized by heating in a drying oven at 180 °C for 12 h. After crystallization, wait for the reactor to cool to room temperature, take out the reaction solution, and centrifuge and wash the reaction solution until the pH value of the centrifuged solution reaches neutral. Dry the solid after centrifugation and washing at 100 °C and calcine it at 550 °C for 6 h to obtain catalyst 1.

[0030] The XRD characterization results of the prepared catalyst are as follows: Figure 1 As shown in the figure, 6.09°, 15.4°, and 23.31° belong to the diffraction peaks of the core FAU, while 7.89°, 8.85°, and 23.21° belong to the diffraction peaks of the outer shell S-1. This indicates that S-1 was successfully encapsulated on Ru@FAU.

[0031] The double-layered metal particle catalyst prepared in Example 1 was used for the catalytic synthesis of pentanediamine, as follows:

[0032] 0.1826 g of lysine hydrochloride was placed in the liner of a 25 ml reactor, dissolved in 10 ml of water, and then 0.101 g of catalyst was added. The mixture was stirred until completely homogeneous, and the pH of the solution was adjusted to 2.0 with phosphoric acid. The reactor was assembled, and the air in the reactor was replaced with nitrogen, followed by replacement with hydrogen. After replacement, the pressure was increased to 2 MPa. The reactor was then opened and the reaction was carried out at 200 °C with a stirring speed of 800 r / min. The reaction was carried out over different time periods of 0-3 hours. After derivatization, the concentrations of lysine and pentanediamine in the post-reaction solution were detected by liquid chromatography. It was found that the lysine conversion rate reached 71.1% and the pentanediamine selectivity reached 70.1% after 2.5 h of reaction.

[0033] The XRD characterization results of catalyst 1 after the reaction are as follows: Figure 2As shown, the diffraction peak of the outer shell S-1 in the catalyst does not decrease significantly, indicating that the catalyst structure is good.

[0034] Example 2

[0035] The synthesis method of the double-layer-coated metal particle catalyst in this embodiment is as follows:

[0036] (1) The synthesis of Ru@FAU is the same as in Example 1;

[0037] (2) Mix 5.084 g of tetrapropylammonium hydroxide with 39.2 g of deionized water and stir the solution until homogeneous. During the stirring process, slowly add 1 g of Ru@FAU catalyst and then add 5.208 g of tetraethyl orthosilicate to the above solution. Stir magnetically for 6 h at room temperature. The solution obtained after stirring is placed in a stainless steel high-pressure reactor and crystallized by heating in a drying oven at 180 °C for 36 h. After crystallization, wait for the reactor to cool to room temperature, take out the reaction solution, and centrifuge and wash the reaction solution until the pH value of the centrifuged solution reaches neutral. Dry the solid after centrifugation and washing at 100 °C and calcine it at 550 °C for 6 h to obtain catalyst 2.

[0038] The XRD characterization results of the prepared catalyst are as follows: Figure 1 As shown in the figure, 6.09°, 15.4°, and 23.31° belong to the diffraction peaks of the core FAU, while 7.89°, 8.85°, and 23.21° belong to the diffraction peaks of the outer shell S-1. This indicates that S-1 was successfully encapsulated on Ru@FAU.

[0039] The double-layered metal particle catalyst prepared in Example 2 was used for the catalytic synthesis of pentanediamine, as follows:

[0040] 0.1826 g of lysine hydrochloride was placed in the liner of a 25 ml reactor, dissolved in 10 ml of water, and then 0.101 g of catalyst was added. The mixture was stirred until completely homogeneous, and the pH of the solution was adjusted to 2.0 with phosphoric acid. The reactor was assembled, and the air in the reactor was replaced with nitrogen, followed by replacement with hydrogen. After replacement, the pressure was increased to 2 MPa. The reactor was then opened and the reaction was carried out at 200 °C with a stirring speed of 800 r / min. The reaction was carried out over different time periods of 0-3 hours. After derivatization, the concentrations of lysine and pentanediamine in the reaction solution were detected by liquid chromatography. It was found that the lysine conversion rate reached 71.9% after 2.5 h of reaction, and the selectivity of pentanediamine reached 64.5%.

[0041] The XRD characterization results of catalyst 2 after the reaction are as follows: Figure 3 As shown, the diffraction peak of the outer shell S-1 in the catalyst does not decrease significantly, indicating that the catalyst structure is good.

[0042] Example 3

[0043] The synthesis method of the double-layer-coated metal particle catalyst in this embodiment is as follows:

[0044] (1) The synthesis of Ru@FAU is the same as in Example 1;

[0045] (2) Mix 5.084 g of tetrapropylammonium hydroxide with 39.2 g of deionized water and stir the solution until uniform. During the stirring process, slowly add 1 g of Ru@FAU catalyst and then add 5.208 g of tetraethyl orthosilicate to the above solution. Stir magnetically for 6 h at room temperature. The solution obtained after stirring is placed in a stainless steel high-pressure reactor and crystallized by heating in a drying oven at 180 °C for 24 h. After crystallization, wait for the reactor to cool to room temperature, take out the reaction solution, and centrifuge and wash the reaction solution until the pH value of the centrifuged solution reaches neutral. Dry the solid after centrifugation and washing at 100 °C and calcine it at 550 °C for 6 h to obtain catalyst 3.

[0046] The XRD characterization results of the prepared catalyst are as follows: Figure 1 As shown in the figure, 6.09°, 15.4°, and 23.31° belong to the diffraction peaks of the core FAU, while 7.89°, 8.85°, and 23.21° belong to the diffraction peaks of the outer shell S-1. This indicates that S-1 was successfully encapsulated on Ru@FAU.

[0047] The double-layered metal particle catalyst prepared in Example 2 was used for the catalytic synthesis of pentanediamine, as follows:

[0048] 0.1826 g of lysine hydrochloride was placed in the liner of a 25 ml reactor, dissolved in 10 ml of water, and then 0.101 g of catalyst was added. The mixture was stirred until completely homogeneous, and the pH of the solution was adjusted to 2.0 with phosphoric acid. The reactor was assembled, and the air in the reactor was replaced with nitrogen, followed by replacement with hydrogen. After replacement, the pressure was increased to 2 MPa. The reactor was then opened and the reaction was carried out at 200 °C with a stirring speed of 800 r / min. The reaction was carried out over different time periods of 0-3 hours. After derivatization, the concentrations of lysine and pentanediamine in the post-reaction solution were detected by liquid chromatography. It was found that the lysine conversion rate reached 81.5% after 2.5 h of reaction, and the selectivity of pentanediamine reached 65.8%.

[0049] The XRD characterization results of catalyst 3 after the reaction are as follows: Figure 4 As shown, the diffraction peak of the outer shell S-1 in the catalyst does not decrease significantly, indicating that the catalyst structure is good.

[0050] Repeatable experiments were conducted on the double-layered metal particle catalyst 3, using the following method:

[0051] The catalyst after the lysine decarboxylation reaction was separated and washed three times by centrifugation with distilled water before being added to the reactor. Then, 10 mL of a 0.1 mol / L L-lysine solution was added, and the pH of the mixed solution was adjusted to 2 by adding phosphoric acid solution. The reactor was sealed and the reaction was carried out at 200℃ under 2 MPa hydrogen atmosphere for 1.5 h. After repeating this process five times, the catalyst activity still achieved 80% lysine conversion and 60% pentanediamine selectivity.

[0052] Comparative Example 1

[0053] Mix 5.084 g of tetrapropylammonium hydroxide with 39.2 g of deionized water and stir the solution until homogeneous. During the stirring process, slowly add 1 g of Ru@FAU catalyst and stir magnetically for 6 h at room temperature.

[0054] The solution obtained after stirring was placed in a stainless steel high-pressure reactor and crystallized using a drying oven at 180°C for 24 hours. After crystallization, the reactor was cooled to room temperature, the reaction solution was removed, and centrifuged and washed until the pH value of the centrifuged solution reached neutral. The solid after centrifugation and washing was dried at 100°C and then calcined at 550°C for 6 hours to obtain catalyst 4.

[0055] The XRD characterization results of the prepared catalyst are as follows: Figure 1 As shown in the figure, only 6.09°, 15.4°, and 23.31° belong to the diffraction peaks of FAU, and the characteristic peak of S-1 does not appear, proving that the catalyst with double-layered encapsulated metal particles was not synthesized.

[0056] In this method, the catalyst is considered to be Ru@FAU. To compare the advantages and disadvantages of the core Ru@FAU and the synthesized silicon-encapsulated core-shell catalyst in the synthesis of pentanediamine and catalyst stability, the catalyst prepared in this example was used to catalyze the synthesis of pentanediamine, as follows:

[0057] 0.1826 g of lysine hydrochloride was placed in the liner of a 25 ml reactor, dissolved in 10 ml of water, and then 0.101 g of catalyst was added. The mixture was stirred until completely homogeneous, and the pH of the solution was adjusted to 2.0 with phosphoric acid. The reactor was then assembled, and the air in the reactor was replaced with nitrogen, followed by replacement with hydrogen. After replacement, the pressure was increased to 2 MPa. The reactor was then opened and the reaction was carried out at 200 °C with a stirring speed of 800 r / min. The reaction was carried out over different time periods of 0-3 hours. After derivatization, the concentrations of lysine and pentanediamine in the reaction solution were detected by liquid chromatography. It was found that the optimal reaction time was 1 h, with a lysine conversion rate of 46.9% and a pentanediamine selectivity of 80%.

[0058] The XRD characterization results of the catalyst after the reaction are as follows: Figure 5 As shown, the diffraction peaks in the XRD gradually weaken as the reaction time increases, and new diffraction peaks appear, indicating that the structure of the catalyst gradually collapses and changes during the reaction.

[0059] Comparative Example 2

[0060] Comparative Example 2 shows the synthesis of a single-layer wrapper, namely Ru@FAU, using the following method:

[0061] Dissolve 2.8 g of sodium hydroxide in 25 ml of deionized water by stirring. Add 0.3375 g of sodium aluminate and stir until clear. Slowly add 12.68 g of silica sol, followed by 0.34 g of ruthenium chloride. Stir at 600 rpm for 4 hours at room temperature. Transfer the resulting solution to a stainless steel hydrothermal synthesis reactor and crystallize at 100 °C for 12 hours. After the hydrothermal synthesis reactor has completely cooled, wash with deionized water until the pH of the filtrate is neutral. Dry overnight at 100 °C to obtain Ru@FAU.

[0062] The Ru@FAU prepared in Comparative Example 1 was used for the catalytic synthesis of pentamethylenediamine, as follows:

[0063] 0.1826 g of lysine hydrochloride was placed in the liner of a 25 ml reactor, dissolved in 10 ml of water, and then 0.101 g of catalyst was added. The mixture was stirred until completely homogeneous, and the pH of the solution was adjusted to 2.0 with phosphoric acid. The reactor was assembled, and the air in the reactor was replaced with nitrogen, followed by replacement with hydrogen. After replacement, the pressure was increased to 2 MPa. The reactor was then opened and the reaction was carried out at 200 °C with a stirring speed of 800 r / min. The reaction was carried out over different time periods of 0-3 hours. After derivatization, the concentrations of lysine and pentanediamine in the reaction solution were detected by liquid chromatography. It was found that the lysine conversion reached 100% after 1 h of reaction, and the selectivity of pentanediamine reached 32%.

[0064] The reproducibility experiment was performed on the single-layer wrapper, Ru@FAU, as follows:

[0065] The catalyst after the lysine decarboxylation reaction was separated and washed three times by centrifugation with distilled water before being added to the reactor. Then, 10 mL of a 0.1 mol / L L-lysine solution was added, and the pH of the mixed solution was adjusted to 2 by adding phosphoric acid solution. The reactor was sealed and the reaction was carried out at 200℃ under 2 MPa hydrogen atmosphere for 1 hour. After repeating this process five times, the catalyst activity still achieved a lysine conversion of 20% and a pentanediamine selectivity of 2%, indicating a significant decrease in catalyst performance.

[0066] Comparative Example 3

[0067] Comparative Example 3 shows the synthesis of a single-layer wrapped Ru@S-1, using the following method:

[0068] After mixing 5.084 g of tetrapropylammonium hydroxide with 39.2 g of deionized water and stirring until homogeneous, 0.34 g of ruthenium chloride and 5.208 g of tetraethyl orthosilicate were added sequentially, and the mixture was magnetically stirred at room temperature for 6 h.

[0069] The solution obtained after stirring was placed in a stainless steel high-pressure reactor and crystallized using a drying oven at 180°C for 12 hours. After crystallization, the reactor was cooled to room temperature, the reaction solution was removed, and centrifuged and washed until the pH value of the centrifuged solution reached neutral. The solid after centrifugation and washing was dried at 100°C and then calcined at 550°C for 6 hours to obtain Ru@S-1.

[0070] The Ru@S-1 catalyst prepared in Comparative Example 3 was used for the catalytic synthesis of pentanediamine, as follows:

[0071] 0.1826 g of lysine hydrochloride was placed in the liner of a 25 ml reactor, dissolved in 10 ml of water, and then 0.101 g of catalyst was added. The mixture was stirred until completely homogeneous, and the pH of the solution was adjusted to 2.0 with phosphoric acid. The reactor was assembled, and the air in the reactor was replaced with nitrogen, followed by replacement with hydrogen. After replacement, the pressure was increased to 2 MPa. The reactor was then opened and the reaction was carried out at 200 °C with a stirring speed of 800 r / min. The reaction was carried out over different time periods of 0-3 hours. After derivatization, the concentrations of lysine and pentanediamine in the reaction solution were detected by liquid chromatography. It was found that no pentanediamine was formed within 3 hours of reaction.

[0072] This invention provides a method for preparing a double-layer-coated metal particle catalyst and its catalytic synthesis of pentanediamine. This method effectively improves the selectivity of pentanediamine in the decarboxylation reaction of lysine, solves the problem of catalyst structural instability in the lysine decarboxylation reaction, and provides a new industrialization opportunity for the chemical decarboxylation of lysine to pentanediamine, showing promising industrial application prospects.

[0073] The present invention has been described in detail above, but it is not limited to the specific embodiments described herein. Those skilled in the art will understand that other modifications and variations can be made without departing from the scope of the invention. The scope of the invention is defined by the appended claims.

Claims

1. The application of a double-layer-coated metal particle catalyst in the decarboxylation synthesis of pentanediamine from lysine, characterized in that: The decarboxylation synthesis of pentanediamine from lysine is carried out in a high-pressure reactor. Lysine or lysine salt, an acid solution of a certain pH, and a double-layered metal particle catalyst are added to the high-pressure reactor to obtain an aqueous solution of pentanediamine. The lysine conversion rate is as high as 81.5%, and the pentanediamine selectivity is 65.8%. The reaction temperature is 120~250℃, the pressure is 0.5~6 MPa, the concentration of lysine or lysine salt is 0.01~3 M, the pH value of the acid solution is 1~8, the molar ratio of the double-layer coated metal particle catalyst to lysine or lysine salt is 1:(0.1~10), the reaction time is 0~3h, and the reaction time is not 0h, the reaction atmosphere is any one of nitrogen, hydrogen, argon, helium or carbon monoxide, the lysine is L-lysine, and the lysine salt is any one of lysine hydrochloride or lysine sulfate; Preparation method of double-layer encapsulated metal particle catalyst: First, the metal nanoparticles M are confined and encapsulated using the rich pore structure of molecular sieve FAU to form M@FAU; then, a directing agent and a silicon source are added for a second encapsulation. After crystallization at a certain temperature and time, the catalyst is washed, dried, and calcined to form a double-layer encapsulated metal particle catalyst with metal nanoparticles as the core. The mass ratio of M@ FAU, directing agent and silicon source is 1:1:1 to 1:10:10; The crystallization temperature is 80-350℃, the crystallization time is 5-72h, the calcination temperature is 300-600℃, and the calcination time is 2-8h. In the M@FAU, M includes any one or more of Pd, Ru, Pt, Au, Cu, and Ni; The silicon source is one or more of silica sol, tetraethyl orthosilicate, and sodium silicate.

2. The application according to claim 1, characterized in that: The structure directing agent is one or more of tetrapropylammonium hydroxide, sodium hydroxide, and BMP.

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