Ru-based hydrogenation catalyst, preparation method and application thereof

Abstract

The application discloses a catalyst for directly and one-step hydrogenation of isophthalonitrile (IPN) into 1,3-cyclohexanedimethylamine (1,3-BAC), a preparation method and application thereof, and belongs to the field of hydrogenation catalysts. The catalyst prepared by adopting a precipitation method has a proper specific surface area and basicity, and is combined with a unique catalyst preparation process, so that the catalyst has the characteristics of high activity, long service life and the like, the conversion rate of isophthalonitrile reaches 100%, and the selectivity of 1,3-cyclohexanediamine reaches 80%. Meanwhile, the catalyst preparation method has the advantages of simple process and low cost, and is suitable for industrial production.

Description

Technical Field

[0001] This invention relates to the field of improved catalyst preparation technology, specifically to a method for preparing a Ru-based catalyst for the preparation of 1,3-cyclohexanedimethylamine from isophthalonitrile and its application. Background Technology

[0002] 1,3-Cyclohexanedimethylamine (1,3-BAC) is an alicyclic amine, a colorless and transparent liquid. It is a high-performance and widely used epoxy resin curing agent, exhibiting excellent resistance to yellowing, good toughness, and fast curing speed. It can be used in epoxy curing agents; floor coatings, especially in applications requiring high color stability; civil engineering adhesives; polyamides; and polyurethane chain extenders. Its characteristics include rapid curing at room temperature; low color intensity and excellent resistance to yellowing; outstanding chemical resistance; and the ability to operate in humid environments. With the listing of m-phenylenediamine (MXDA) as a toxic chemical, the demand for 1,3-BAC as a substitute has increased dramatically, thus giving it high application and commercial value in industry.

[0003] Existing technology

[0004] The obtained IPN needs to go through two stages.

[0005] Hydrogenation reaction: The first stage involves hydrogenation of the cyano group to obtain MXDA, and the second stage involves hydrogenation of the benzene ring to obtain 1,3-BAC. The biggest technical challenge of this route lies in the fact that the imine intermediate produced by the hydrogenation of the cyano group in the first stage is chemically highly reactive. It readily undergoes various side reactions such as condensation, ammonolysis, and cross-linking with the phenylenediamine intermediate and the final product cyclohexanedimethylamine in the system to form large molecular polymers. These polymers adsorb onto the catalyst surface, blocking the reactive sites and severely reducing catalytic activity and durability.

[0006] Secondly, in the second step of the hydrogenation of m-phenylenediamine, the reduction of the benzene ring also utilizes various metals with excellent hydrogenation properties, such as ruthenium, rhodium, palladium, nickel, and cobalt. The substances in the second-stage MXDA hydrogenation reaction system typically have multiple hydrogenation active sites, and amino or aminomethyl groups are easily hydrogenated, leading to deep hydrogenation of the target product, reducing yield and selectivity, and posing significant technical challenges. The biggest problem with the MXDA hydrogenation process is that MXDA itself, as a key monomer for the production of specialty nylon MXD6, is expensive, and the overall techno-economic issues of the process have not been fundamentally and effectively resolved.

[0007] In summary, the two-stage production of 1,3-BAC, including the first reaction stage of producing MXDA from IPN and the second reaction stage of producing 1,3-BAC from the hydrogenation of MXDA, faces challenges such as complex reactions and difficult separation, leading to the complexity and uneconomical nature of the two-step process. Therefore, combining the two-stage reaction into a one-step direct production of 1,3-BAC from isophthalonitrile has significant commercial value and implications. Summary of the Invention

[0008] In view of the prior art, the purpose of this invention is to provide a Ru-based catalyst preparation method for the one-step direct preparation of 1,3-cyclohexanedimethylamine from isophthalonitrile and its application. The catalyst preparation method is simple, the conditions are mild, the cost is low, and it has good activity and stability.

[0009] This invention is achieved through the following technical solution:

[0010] 1. A method for preparing a Ru-based catalyst for one-step preparation of 1,3-BAC is provided, characterized in that Ru is loaded onto a magnesium aluminum oxide catalyst by co-precipitation or precipitation with metal salts such as Mg and Al or other supports in water at 40-120°C, using sodium carbonate or other bases as precipitants. After cooling to room temperature, the catalyst is filtered, washed, dried, and calcined at 150-700°C in a hydrogen atmosphere to obtain the hydrogenation catalyst.

[0011] The mass ratios of each component in the catalyst preparation process are as follows: the mass ratio of support: Mg:Al is 1:0-0:1, preferably 7:1-6:1; the Ru loading is 0.2-20 wt.%, preferably 2-10 wt.%.

[0012] 2. Based on the above technical solution, the preparation process of the carrier is as follows: under stirring conditions, magnesium oxide precursor, aluminum oxide precursor or other metal oxide and Ru metal precursor are fully mixed in water, and alkali is added to adjust the pH of the mixture to 8-12. After aging at 40-120℃ for 1-24h, a mixture is obtained. The mixture is filtered, and after solid drying and grinding, spherical particles of 10-200μm are obtained. The particles are calcined at 150-700℃ for 1-15h in a hydrogen atmosphere (e.g., inert gas-hydrogen mixture / or pure hydrogen) to obtain the Ru-based catalyst.

[0013] The other carriers are selected from one or more of Al2O3, MgO, TiO2, ZrO2, ZnO, C, etc.

[0014] 3. Based on the above technical solution, the catalyst includes a support and an active center supported on the support; characterized in that the active component includes active components Ru and X, wherein X represents at least one or more elements from the group consisting of gold, palladium, rhodium, nickel, zinc, platinum, ruthenium, silver, cobalt, copper, iridium, scandium, yttrium, lanthanum and neodymium;

[0015] The carrier is a composite carrier containing magnesium and aluminum oxides, that is, a composition formed by magnesium oxide, aluminum oxide and other metal oxides. The magnesium and aluminum oxides are selected from one or more of the following: a mixture of magnesium oxide and aluminum oxide, magnesium aluminum oxide, spinel, hydrotalcite, etc. The other carriers are selected from one or more of the following: Al2O3, MgO, C, etc.

[0016] 4. Based on the above technical solutions, the precursors of the active components Ru and X are one or more of any soluble metal acids or salts of the corresponding metals; for example: the precursor of Ru is one or more of ruthenium trichloride, ruthenium nitrate, ruthenium acetate, potassium ruthenium chlororuthenate, ruthenium carbonyl chloride, ruthenium tetracarbonyl dichloride, and ruthenium iodide; the precursor of Pd is one or more of palladium chloride, palladium nitrate, palladium acetate, ferrocene diphenylphosphine dichloride, tetraphenylphosphine palladium, dichlorodiphenylphosphine palladium, and palladium on carbon; the precursor of platinum is one or more of platinum nitrate, chloroplatinic acid, sodium chloroplatinate, platinum chloride, dichlorotetraammineplatinum(II), and hexahydroxyplatinic acid di(ethanolammonium).

[0017] 5. Based on the above technical solution, in the carrier component, the precursor of magnesium oxide is one or more of magnesium nitrate, magnesium chloride, magnesium sulfate, and magnesium phosphate; the precursor of aluminum oxide is one or more of aluminum nitrate, aluminum chloride, aluminum hydroxide, aluminum phosphate, and aluminum sulfate; and the other metal precursors are one or more of the corresponding metal nitrates, oxides, hydroxides, compounds, or complexes.

[0018] The alkali-adjusted mixture is an aqueous solution of one or more of sodium carbonate and sodium hydroxide.

[0019] 6. Based on the above technical solution, the active components Ru and X (selected from at least one or more elements in the group consisting of gold, palladium, rhodium, nickel, zinc, platinum, ruthenium, silver, cobalt, copper, iridium, scandium, yttrium, lanthanum and neodymium) and the support components contained in the catalyst exist in the form of metals and / or oxides or multimetallic complexes in the catalyst.

[0020] 7. Based on the above technical solution, the specific synthesis method of 1,3-BAC is as follows: Catalytic hydrogenation is carried out in a fixed-bed reactor. A catalyst is loaded, and isophthalonitrile and solvent are prepared into a solution with a mass ratio of 0.5 wt.%-20 wt.%, preferably 2 wt.%-10 wt.%. The solvent includes tetrahydrofuran, 1,4-epoxyhexacyclohexane, tert-butanol, isopropanol, methylimidazolium, etc., which have good solubility for IPN. During the liquid transport process, a heating cable is used to heat the solution to improve the solubility of isophthalonitrile in the solvent. The solution is added to the fixed-bed reactor using a metering pump, and the reactor is operated at a temperature of 80–200℃, a pressure of 1–10 MPa, and a liquid hourly space velocity of 0.5–2 h⁻¹. -1The hydrogenation reaction was carried out under the conditions of a hydrogen:isophthalonitrile molar ratio of 5 to 10:1 and an ammonia addition of 1 to 20 wt.% of IPN mass fraction, and then 1,3-cyclohexanedimethylamine was obtained.

[0021] The catalyst prepared by precipitation method has suitable specific surface area and basicity. Combined with a unique catalyst preparation process, the catalyst exhibits high activity, is not prone to pore blockage, and has a long service life. The conversion rate of isophthalonitrile reaches 100%, and the selectivity of 1,3-cyclohexanediamine reaches 80%. At the same time, the catalyst preparation method is simple and low-cost, making it suitable for industrial production.

[0022] Compared with the prior art, the advantages of the present invention are:

[0023] (1) The method for synthesizing Ru-based catalysts in this invention firstly uses a precipitation method to prepare ruthenium-based catalysts. These catalysts have high Ru dispersibility and high activity. When the prepared catalysts are added to the reaction, they improve the hydrogenation reaction performance.

[0024] (2) The Ru-based catalyst obtained by this invention has a strong recycling capacity, with a lifespan of over 1000 hours. Moreover, the catalyst is easy to recover; it only requires hydrogen pre-reduction treatment before it can be reused in the next batch of 1,3-BAC synthesis reaction.

[0025] (3) The method of synthesizing 1,3-BAC in this invention has the advantages of high chemical stability, simple process flow, mild reaction conditions and high yield. Attached Figure Description

[0026] Figure 1 The image shows a TEM image of the Ru / MgAlO catalyst prepared in Example 1. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to specific embodiments. The scope of protection of the present invention includes, but is not limited to, the following embodiments. Any modifications to the details and form of the technical solution of the present invention without departing from the meaning and scope of this application shall fall within the scope of protection of the present invention.

[0028] Example 1

[0029] Catalyst preparation:

[0030] Weigh 38.1g Mg(NO3)2·6H2O, 7.2g Al(NO3)3·9H2O (m(MgO):m(Al2O3) = 6:1, mass ratio, the same below), and 0.79g RuCl3 (mass fraction 37%, solvent: water), dissolve in 100mL deionized water, and stir to obtain solution I. Weigh 19.1g Na2CO3 and dissolve in 100mL deionized water, and stir to obtain solution II. At 80℃, add solutions I and II dropwise evenly to a reactor containing 200mL deionized water. After the addition is complete, continue the reaction for 2 hours, measure the pH of the solution to be 9.5, and wash with deionized water until no Cl is found. － The sample was filtered, dried, and a blue-green solid powder was obtained. Pre-reduction under hydrogen atmosphere at 400℃ for 2 h yielded a black solid powder. The Ru content of the Ru / MgAlO-1 catalyst product was 2 wt.%, and the specific surface area was 205.7 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al (composite oxide) in the support was 6.5:1.

[0031] Comparative Example 1

[0032] The catalyst preparation process and conditions were the same as in Example 1, except that 0.019 g RuCl3 was used instead of 0.78 g RuCl3. The Ru content of the Ru / MgAlO-D1 catalyst product was 0.1 wt.%, and the specific surface area was 195.6 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0033] Comparative Example 2

[0034] The catalyst preparation process and conditions were the same as in Example 1, except that the completely dried catalyst was calcined in an air atmosphere instead of H2 gas. The Ru content of the Ru / MgAlO-D2 catalyst product was 4 wt.%, and the specific surface area was 190.2 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0035] Example 2

[0036] The catalyst preparation process was the same as in Example 1, except that 25.45g Mg(NO3)2·6H2O was used instead of 38.1g Mg(NO3)2·6H2O, and 0.563g RuCl3 (37% by mass, water as solvent) was used instead of 0.79g RuCl3 (37% by mass). These solutions were dissolved in 100mL of deionized water and stirred to obtain solution I. 13.86g Na2CO3 was used instead of 19.1g Na2CO3 and dissolved in 100mL of deionized water, and stirred to obtain solution II. Solutions I and II were uniformly added dropwise to a reactor containing 200mL of deionized water at 80℃. After the addition was complete, the reaction continued for 2 hours. The pH of the solution was measured to be 9.5, and the solution was washed with deionized water until no Cl- was found. － The sample was filtered, dried, and a blue-green solid powder was obtained. Pre-reduction under hydrogen atmosphere at 400℃ for 2 h yielded a black solid powder. The Ru content of the Ru / MgAlO-2 catalyst product was 4 wt.%, and the specific surface area was 204.2 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 4.5:1.

[0037] Example 3

[0038] The catalyst preparation process was the same as in Example 1, except that 14.4 g Al(NO3)3·9H2O was used instead of 38.1 g Mg(NO3)2·6H2O and 7.2 g Al(NO3)3·9H2O, and 0.23 g RuCl3 (37% by mass, aqueous solution) was used instead of 0.79 g RuCl3 (37% by mass, aqueous solution). The solutions were dissolved in 100 mL of deionized water and stirred to obtain solution I. 3.2 g Na2CO3 was used instead of 19.1 g Na2CO3 and dissolved in 100 mL of deionized water, and stirred to obtain solution II. Solutions I and II were uniformly added dropwise to a reactor containing 200 mL of deionized water at 80 °C. After the addition was complete, the reaction continued for 2 hours. The pH of the solution was measured to be 9.8, and the solution was washed with deionized water until no Cl- was found. － The sample was filtered, dried, and a blue-green solid powder was obtained. This powder was then pre-reduced under a hydrogen atmosphere at 400°C for 2 hours to obtain a black solid powder. The resulting catalyst was Ru / Al₂O₃, with a Ru content of 4 wt.% and a specific surface area of ​​167.4 m². 2 / g.

[0039] Example 4

[0040] The catalyst preparation process and conditions were the same as in Example 1, except that 0.143 g of RuCl3 (37% by mass, aqueous solution) was used instead of 0.79 g of RuCl3 (37% by mass, aqueous solution), dissolved in 100 mL of deionized water. The Ru / MgAlO-4 catalyst product had a Ru content of 2 wt.% and a specific surface area of ​​192.8 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0041] Example 5

[0042] The catalyst preparation process and conditions were the same as in Example 1, except that 2.1 g of RuCl3 (37% by mass, aqueous solution) was used instead of 0.79 g of RuCl3 (37% by mass, aqueous solution), dissolved in 100 mL of deionized water. 19.6 g of Na2CO3 was used instead of 19.1 g dissolved in 100 mL of deionized water. The Ru content of the Ru / MgAlO-5 catalyst product was 10 wt.%, and the specific surface area was 186.4 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0043] Example 6

[0044] The catalyst preparation process and conditions were the same as in Example 1, except that 0.65 g of ruthenium acetate (Ru content 40-48%, 45% in this case, aqueous solution) was used instead of 0.79 g of RuCl3 (mass fraction 37%, aqueous solution). The resulting Ru / MgAlO-6 catalyst product had a Ru content of 4 wt.% and a specific surface area of ​​196.3 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0045] Example 7

[0046] The catalyst preparation process and conditions were the same as in Example 1, except that 0.74 g of RhCl3·3H2O (Rh content 39.4%) was used instead of 0.79 g of RuCl3 (37% by mass, aqueous solution). The resulting Rh / MgAlO-7 catalyst product had an Rh content of 4 wt.% and a specific surface area of ​​210.5 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0047] Example 8

[0048] The catalyst preparation process and conditions were the same as in Example 1, except that 7.23 g of NaOH was used instead of 19.1 g of Na₂CO₃ dissolved in 100 mL of deionized water. The resulting Ru / MgAlO₄ catalyst product had a Ru content of 4 wt.% and a specific surface area of ​​204.2 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0049] Example 9

[0050] The catalyst preparation process and conditions were the same as in Example 1. 0.79 g RuCl3 (37% by mass, aqueous solution) was dissolved in 100 mL of deionized water and stirred to obtain solution I. 0.35 g Na2CO3 was weighed and dissolved in 100 mL of deionized water and stirred to obtain solution II. At 80 °C, solutions I and II were uniformly added dropwise to 200 mL of deionized water containing 7 g of dispersed activated carbon. After the addition was complete, the reaction continued for 2 hours, followed by washing with deionized water until no Cl- was detected. － The product was present; after reaction, the pH was determined to be 9.5. It was then filtered, dried, and pre-reduced at 400℃ under a hydrogen atmosphere for 2 hours. The resulting Ru / C catalyst product had a Ru content of 4 wt.% and a specific surface area of ​​1328 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0051] Example 10

[0052] The catalyst preparation process and conditions were the same as in Example 1, except that 38.1 g of Mg(NO3)2·6H2O, 7.2 g of Al(NO3)3·9H2O (m(MgO):m(Al2O3) = 6:1), 0.79 g of RuCl3 (37% mass fraction, aqueous solution) and 4 g of Co(NO3)2·6H2O were weighed and dissolved in 100 mL of deionized water, and stirred to obtain solution I. 20.7 g of Na2CO3 was used instead of 19.1 g of Na2CO3 and dissolved in 100 mL of deionized water, and stirred to obtain solution II. Solutions I and II were uniformly added dropwise to a reactor containing 200 mL of deionized water at 80 °C. After the addition was complete, the reaction continued for 2 h, and the pH of the solution was measured to be 9.5. The solution was washed with deionized water until no Cl- was found. － The sample was filtered, dried, and a blue-green solid powder was obtained. Pre-reduction under hydrogen atmosphere at 400℃ for 2 h yielded a black solid powder. The prepared Ru-Co / MgAlO catalyst had a Ru content of 3.6 wt.%, a Co content of 10 wt.%, and a specific surface area of ​​215.9 m². 2 / g. XRF testing of the catalyst support revealed that the mass ratio of Mg to Al in the support was 6.5:1.

[0053] Example 11

[0054] The catalysts obtained in Examples 1-10 and Comparative Examples 1-2 were used for the one-step IPN preparation of 1,3-BAC under the same conditions, as follows:

[0055] Based on the above technical solution, the specific synthesis method of 1,3-BAC is as follows: Catalytic hydrogenation is carried out in a fixed-bed reactor, with 50g of Ru / MgAlO catalyst added. Isophthalonitrile and isopropanol are prepared into a solution with a mass ratio of 1:10. During liquid transport, a 60℃ heating cable is used to heat the pipeline to improve the solubility of isophthalonitrile in the solvent. A metering pump is used to add the solution to the fixed-bed reactor at a temperature of 110℃, an H2 pressure of 2MPa, and a liquid hourly space velocity of 0.5h⁻¹. -1 The hydrogenation reaction was carried out under conditions of hydrogen flow rate of 300 mL / min and ammonia addition of 2 wt.% of IPN mass fraction to obtain 1,3-cyclohexanedimethylamine. After the reaction, the feed solution was taken out at regular intervals, and benzyl alcohol was added as an internal standard. The reaction results were analyzed by gas chromatography (GC). The conversion rate of isophthalonitrile and the selectivity of 1,3-cyclohexanedimethylamine were calculated after 200 h and 400 h of reaction, respectively.

[0056]

[0057] Comparing Examples 1-10 and Comparative Examples 1-2 in the table, the presence of the active component ruthenium maintained high activity and selectivity for a long reaction period. The catalyst recovery rate was high, and the particle size of the catalyst showed no significant increase after 400 hours of reaction, making it suitable for continuous production.

[0058] Figure 1 The image shown is a transmission electron microscope (TEM) image of the catalyst prepared in Example 1, which shows that the catalyst has excellent dispersion.

Claims

1. A method for preparing a Ru-based hydrogenation catalyst, characterized in that, In water at 40-120℃, using alkali as a precipitant, Ru precursor, or Ru precursor and X metal precursor with metal salts of Mg and / or Al are co-precipitated or precipitated to load Ru and X metals onto a metal oxide support containing magnesium and / or aluminum. After cooling to room temperature, filtering, washing, drying, and calcining in a hydrogen atmosphere at 150-700℃, a hydrogenation catalyst is obtained. The mass ratios of each component in the catalyst preparation process are as follows: the mass ratio of support:Mg:Al is 1:0-0:1, preferably 7:1-5:1; the Ru loading in the catalyst is 0.2-20 wt.%, preferably 2-10 wt.%.

2. The method for preparing the catalyst according to claim 1, characterized in that, The preparation process is as follows: under stirring conditions, magnesium oxide precursor and / or aluminum oxide precursor (metal salts of Mg and / or Al) and Ru metal precursor are thoroughly mixed in water, then alkali is added to precipitate uniformly, and the mixture is aged at 40-120℃ for 1-24 hours to obtain a mixture. The mixture is filtered, the solid is dried and ground, and then calcined at 150-700℃ for 1-15 hours in a hydrogen atmosphere (e.g., an inert atmosphere gas (e.g., nitrogen and / or argon)-hydrogen mixture / or pure hydrogen) to obtain the Ru-based catalyst.

3. The method for preparing the catalyst according to claim 1 or 2, characterized in that, The catalyst includes a support and active centers supported on the support; the active components include active components Ru and X, wherein X represents at least one or more elements from the group consisting of gold, palladium, rhodium, nickel, zinc, platinum, ruthenium, silver, cobalt, copper, iridium, scandium, yttrium, lanthanum and neodymium; the loading of X in the catalyst is 2-6 wt.%, preferably 3-4.5 wt.%; The carrier is a composite carrier containing magnesium and aluminum oxides, that is, a composition formed by magnesium oxide, aluminum oxide and magnesium aluminum oxides, wherein the magnesium aluminum oxides are selected from one or more of the following: a mixture of magnesium oxide and aluminum oxide, magnesium aluminum oxide, spinel, hydrotalcite, etc.

4. The method for preparing the catalyst according to claim 1 or 3, characterized in that, The precursors of the active components Ru and X are one or more of any soluble metal acids or salts of the corresponding metals. Ru's precursors are one or more of the following: ruthenium trichloride, ruthenium nitrate, ruthenium acetate, potassium ruthenium chlororuthenium, carbonyl ruthenium chloride, tetracarbonyl diruthenium dichloride, and ruthenium iodide. The palladium precursor is one or more of palladium chloride, palladium nitrate, palladium acetate, palladium dichloride, tetraphenylphosphine palladium, dichlorotriphenylphosphine palladium, and palladium on carbon; The precursors of platinum are one or more of the following: platinum nitrate, chloroplatinic acid, sodium chloroplatinate, platinum chloride, dichlorotetramineplatinum(II), and di(ethanolammonium)hexahydroxyplatinate; The gold precursor is one or more of potassium chloroaurate, tetrachloroauric acid, and gold trichloride; The precursors of rhodium are one or more of the following: ammonium rhodium chloride, rhodium bromide, rhodium chloride, rhodium sulfate, rhodium nitrate, rhodium chloride (trihydrate), and rhodium chloride triphenylphosphine. The precursors of nickel are one or more of nickel nitrate, nickel hypophosphite, nickel carbonate, and nickel sulfate; The zinc precursor is one or more of zinc tungstate, zinc propionate, zinc oxalate, and zinc nitrate; The precursor of silver is one or more of silver perchlorate, silver phosphate, silver cyanate, silver nitrite, silver nitrate, silver sulfide, and silver lactate. The precursors of cobalt are one or more of cobalt phosphate, potassium cobalt cyanide, cobalt carbonyl, cobalt sulfate, and cobalt phthalocyanine; The copper precursor is one or more of the following: copper tartrate, copper acetate, cuprous acetate, cuprous oxide, copper oxalate, copper nitrate, copper phthalocyanine, and copper pyrophosphate. The precursor of iridium is one or more of ammonium chloroiridate, iridium bromide, chloroiridic acid, carbonyl iridium, and chloroiridic acid hydrate; The precursors of scandium are one or more of scandium nitrate, scandium sulfide, scandium trichloride, scandium perchlorate, scandium chloride hexahydrate, scandium acetate, and scandium acetate hydrate. The precursors of yttrium are one or more of yttrium nitrate, yttrium phosphate, yttrium perchlorate, yttrium chloride, and yttrium metaphosphate. Lanthanum precursors are one or more of lanthanum sulfide, lanthanum acetate, lanthanum nitrate, lanthanum metaphosphate, lanthanum carbonate, lanthanum chloride, and lanthanum perchlorate. The precursors of neodymium are one or more of neodymium acetate, neodymium trichloride, neodymium nitrate, neodymium carbonate, neodymium sulfate, neodymium perchlorate, and neodymium oxalate hexahydrate.

5. The method for preparing the catalyst according to claim 1, characterized in that, In the carrier component, the precursor of magnesium oxide is one or more of magnesium nitrate, magnesium chloride, magnesium sulfate, and magnesium phosphate. The precursor of the alumina is one or more of aluminum nitrate, aluminum chloride, aluminum hydroxide, aluminum phosphate, and aluminum sulfate; the other metal precursor is one or more of the corresponding metal nitrate, oxide, hydroxide, compound, or complex. The alkali-adjusted mixture is an aqueous solution of one or more of sodium carbonate and sodium hydroxide, with a concentration of 5% to 30%.

6. The method for preparing the catalyst according to any one of claims 1-5, characterized in that: The active components Ru and X (selected from at least one or more elements from the group consisting of gold, palladium, rhodium, nickel, zinc, platinum, ruthenium, silver, cobalt, copper, iridium, scandium, yttrium, lanthanum and neodymium) and the support components in the catalyst exist in the catalyst in the form of metals and / or oxides, or multimetallic complexes.

7. A catalyst prepared by any one of the preparation methods according to claims 1-6.

8. The application of the catalyst according to claim 7 in the catalytic hydrogenation of isophthalonitrile to 1,3-cyclohexanedimethylamine, specifically as follows: The catalytic hydrogenation reaction is carried out in a fixed-bed reactor, the catalyst is loaded, and isophthalonitrile (IPN) and solvent are prepared into a solution with a mass ratio of 0.5 wt.%-20 wt.%, preferably 2 wt.%-10 wt.%, wherein the solvent comprises: One or more solvents selected from tetrahydrofuran, 1,4-epoxyhexacyclohexane, tert-butanol, isopropanol, and methylimidazole are used to provide good solubility for isophthalonitrile in solvents. During liquid transport, a pipe with a heating element on its wall is used to enhance the solubility of isophthalonitrile in the solvent. A metering pump is used to add the solution to the fixed-bed reactor, operating at a temperature of 80–200℃, a pressure of 1–10 MPa, and a liquid hourly space velocity of 0.5–2 h⁻¹. -1 The hydrogenation reaction was carried out under the conditions of a hydrogen:isophthalonitrile molar ratio of 5 to 10:1 and an ammonia addition amount of 1 to 10 wt.% of IPN mass fraction, and then 1,3-cyclohexanedimethylamine was obtained.

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