Supported catalyst, process for its preparation and use thereof

Abstract

The application provides a supported catalyst and a preparation method and application thereof. The supported catalyst comprises M1, M2, a carbon source and a metal oxide carrier; the M1 comprises Co and / or Ni; and the M2 comprises one or more of Cu, Fe, Zn, Mn and Mo. The preparation method of the catalyst comprises the following steps: dissolving M1 precursors and carbon source precursors in water to obtain solution A; adding the carrier into the solution A and performing first rotary evaporation to obtain solid B, and performing first heat treatment on the solid B under an inert atmosphere to obtain solid C; dissolving M2 precursors and carbon source precursors in water to obtain solution D; adding the solid C into the solution D and performing second rotary evaporation to obtain solid E, and performing second heat treatment on the solid E under an inert atmosphere. The catalyst is applied to the synthesis of ethylenediamine by the amination of ethylene glycol. The method provided by the application has simple process, low catalyst cost, higher ethylenediamine selectivity and better stability in the synthesis of ethylenediamine by the amination of ethylene glycol.

Description

Technical Field

[0001] This invention belongs to the field of heterogeneous catalysis technology, and particularly relates to a supported catalyst, its preparation method, and its application. Background Technology

[0002] Ethylenediamine (EDA) is an important chemical raw material and fine chemical intermediate. It possesses alkaline and surface-active properties and is widely used in the production of chelating agents, pesticide fungicides, and reactive dye intermediates. It can also serve as a raw material for pharmaceuticals and textile finishing agents, and as an epoxy resin curing agent, emulsion stabilizer, and antistatic agent. my country's demand for ethylenediamine is approximately 200,000 tons per year, with a demand growth rate exceeding 20%, and nearly 30% of the market demand relies on imports.

[0003] There are two main methods for producing ethylenediamine (EDA): the dichloroethane method and the ethanolamine method. The dichloroethane method uses 65% (w) liquid ammonia and dichloroethane in a tubular reactor to produce EDA via a hot-pressurization ammonolysis reaction. The reaction temperature is 93–100°C, and the reaction pressure is approximately 4.9 MPa. The conversion rate of dichloroethane reaches 100.0%, and the product selectivity is about 40% for EDA. However, the dichloroethane method causes severe pollution, equipment corrosion, and high investment costs. In contrast, the ethanolamine method uses ethanolamine as a raw material to synthesize EDA through reductive ammoniation or condensation ammoniation. This method has advantages such as less pollution and lower investment costs, making it a cleaner EDA synthesis process. For example, patent EP-A0839575 discloses a copper- or ruthenium-modified cobalt- or nickel-based catalyst that exhibits high EDA selectivity in the reductive ammoniation reaction of ethanolamine. Patent CN101215239 discloses a method for synthesizing ethylenediamine by condensation and amination of ethanolamine catalyzed by mordenite. The reaction is carried out under the conditions of pressure 2.0-2.5 MPa, temperature 300-350℃, mass ratio of ammonia to ethanolamine (6-12):1, and time 20-30s. The product is separated by distillation to obtain ethylenediamine.

[0004] Compared to the dichloroethane method, the ethanolamine method for synthesizing ethylenediamine has advantages such as less pollution and a cleaner process. However, industrial ethanolamine is prepared from high-purity ethylene oxide. For example, patent DE102005019373.0 discloses a method for synthesizing ethanolamine from ethylene oxide and ammonia using inorganic ion exchangers, with ammoniaation products including monoethanolamine, diethanolamine, and triethanolamine. Ethylene oxide is flammable and explosive, and difficult to transport; therefore, the ethanolamine method is limited by the supply of ethylene oxide as a raw material.

[0005] my country's ethylene glycol production capacity has increased rapidly in recent years, reaching 21 million tons in 2022. Using ethylene glycol as a raw material to synthesize ethylenediamine can address both the rapid expansion of ethylene glycol production capacity and the current supply shortage of ethylenediamine. Patent EP0252424A2 discloses a method for synthesizing ethylenediamine from ethylene glycol using Ru-Co / γ-Al₂O₃ at 180℃, 200 bar, and a hydrogen-to-ethylene glycol molar ratio of 0.5. The highest ethylene glycol conversion rate was 43.4%, and the highest ethylenediamine selectivity was 57.0%. However, the use of precious metal catalysts leads to higher production costs for ethylenediamine.

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

[0007] The purpose of this invention is to provide a supported catalyst, its preparation method, and its application to solve the above-mentioned problems.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] The supported catalyst provided by the present invention includes M1, M2, a carbon source and a metal oxide support; the support includes any one of alumina, aluminum hydroxide, zirconium oxide, zirconium hydroxide, silicon oxide and cerium oxide;

[0010] M1 includes Co and / or Ni;

[0011] The M2 includes one or more of Cu, Fe, Zn, Mn, and Mo.

[0012] M1 accounts for 5 to 30 wt% of the carrier mass, M2 accounts for 1 to 10 wt% of the carrier mass, and the carbon source accounts for 1 to 6 wt% of the carrier mass.

[0013] Preferably, M1 accounts for 6-25 wt% of the carrier mass, M2 accounts for 2-8 wt% of the carrier mass, and the carbon source accounts for 2-5 wt% of the carrier mass.

[0014] Optionally, the percentage of M1 by mass of the support can be any value between 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, 22wt%, 23wt%, 24wt%, 25wt%, 26wt%, 28wt%, and 30wt%, the percentage of M2 by mass of the support can be any value between 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, and 10wt%, and the percentage of the carbon source by mass of the support can be any value between 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, and 6wt%.

[0015] The present invention also provides a method for preparing the supported catalyst described above, comprising the following steps:

[0016] S1: Dissolve the M1 precursor and the carbon source precursor in water to obtain solution A;

[0017] Step S1 satisfies one or more of the following conditions:

[0018] a. The M1 precursor includes one or more of cobalt nitrate, cobalt acetate, nickel nitrate, and nickel acetate;

[0019] b. The molar ratio of the carbon source precursor to M1 is 0.10 to 0.40:1;

[0020] Optionally, the molar ratio of the carbon source precursor to M1 can be any value between 0.10:1, 0.20:1, 0.30:1, and 0.40:1;

[0021] c. The concentration of M1 ions in solution A is 0.5–3.5 mol / L.

[0022] Optionally, the ion concentration of M1 in solution A can be any value between 0.5 mol / L, 1.0 mol / L, 1.5 mol / L, 2.0 mol / L, 2.5 mol / L, 3.0 mol / L, and 3.5 mol / L.

[0023] S2: Add a carrier to solution A obtained in S1 and perform a first rotary evaporation to obtain solid B. Then, subject solid B to a first heat treatment under an inert atmosphere to obtain solid C.

[0024] Step S2 satisfies one or more of the following conditions:

[0025] d. The carrier comprises one or more of alumina, aluminum hydroxide, zirconium oxide, zirconium hydroxide, silicon oxide, and cerium oxide;

[0026] e. The content of M1 in the system accounts for 5 to 30 wt% of the carrier;

[0027] f. The temperature of the first rotary evaporation is 40–70°C, and the time is 4–12 hours;

[0028] Optionally, the temperature of the first rotary evaporation can be any value between 40℃, 45℃, 50℃, 55℃, 60℃, 65℃ and 70℃, and the time can be any value between 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h and 12h.

[0029] g. The heating rate of the first heat treatment is 0.5–1 °C / min;

[0030] Optionally, the heating rate of the first heat treatment can be any value between 0.5℃ / min, 0.6℃ / min, 0.7℃ / min, 0.8℃ / min, 0.9℃ / min and 1℃ / min;

[0031] h. The target temperature for the first heat treatment is 350–600℃, and the holding time is 4–6 hours.

[0032] Optionally, the target temperature of the first heat treatment can be any value between 350℃, 400℃, 450℃, 500℃, 550℃ and 600℃, and the holding time can be any value between 4h, 4.5h, 5h, 5.5h and 6h.

[0033] S3: Dissolve the M2 precursor and the carbon source precursor in water to obtain solution D;

[0034] Step S3 satisfies one or more of the following conditions:

[0035] i. The M2 precursor includes one or more of copper nitrate, ferric nitrate, manganese nitrate, and ammonium molybdate;

[0036] j. The content of M2 in the system accounts for 1 to 10 wt% of the carrier;

[0037] k. The molar ratio of the carbon source precursor to M2 is 0.10 to 0.40:1;

[0038] Optionally, the molar ratio of the carbon source precursor to M2 can be any value between 0.10:1, 0.20:1, 0.30:1, and 0.40:1;

[0039] l. The ion concentration of M2 in solution D is 0.1–1.2 mol / L.

[0040] Optionally, the ion concentration of M2 in solution D can be any value between 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, and 1.2 mol / L.

[0041] S4: Add the solid C obtained from S2 to the solution D obtained from S3 and perform a second rotary evaporation to obtain solid E. Then, subject solid E to a second heat treatment under an inert atmosphere to obtain the final product.

[0042] Step S4 satisfies one or more of the following conditions:

[0043] m. The temperature of the second rotary evaporation is 40–70°C, and the time is 4–12 hours;

[0044] Optionally, the temperature of the second rotary evaporation can be any value between 40°C, 45°C, 50°C, 55°C, 60°C, 65°C and 70°C, and the time can be any value between 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h and 12h.

[0045] n. The heating rate of the second heat treatment is 0.5–1 °C / min;

[0046] Optionally, the heating rate of the second heat treatment can be any value between 0.5℃ / min, 0.6℃ / min, 0.7℃ / min, 0.8℃ / min, 0.9℃ / min and 1℃ / min;

[0047] o. The target temperature for the second heat treatment is 200–350°C, and the holding time is 4–6 hours.

[0048] Optionally, the target temperature for the second heat treatment can be any value between 200°C, 250°C, 300°C, and 350°C, and the holding time can be any value between 4h, 4.5h, 5h, 5.5h, and 6h.

[0049] Preferably, the preparation method further satisfies one or more of the following conditions:

[0050] p. The carbon source precursors mentioned in steps S1 and S3 include one or more of glucose, fructose, starch, and cyclodextrin;

[0051] q. The content of M1 in the system accounts for 6-8 wt% of the carrier;

[0052] r. The molar ratio of the carbon source precursor to M1 in step S1 is 0.10 to 0.35:1;

[0053] s. The ion concentration of M1 in solution A is 0.6–2.5 mol / L;

[0054] The content of M2 in the system accounts for 2 to 8 wt% of the carrier;

[0055] u. The molar ratio of the carbon source precursor to M2 in step S3 is 0.10 to 0.35:1;

[0056] v. The ion concentration of M2 in solution D is 0.3–1.0 mol / L;

[0057] w. The carbon source in the system accounts for 1 to 6 wt% of the carrier;

[0058] Preferably, the carbon source accounts for 2 to 5 wt% of the carrier;

[0059] x. The target temperature for the first heat treatment is 400-500°C; further optimization of the temperature can improve the reduction degree of component M1 and expose more active centers;

[0060] y. The target temperature for the second heat treatment is 250–300°C. Performing the second heat treatment at 250–300°C can promote better synergy between M2 and M1.

[0061] This invention also provides applications of the supported catalyst, including its use in the amination of ethylene glycol to synthesize ethylenediamine, with the following specific application conditions:

[0062] The catalyst was crushed to 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, ethylene glycol solution, and hydrogen were introduced. The reaction pressure was controlled at 6.0-12.0 MPa, the reaction temperature at 120-148°C, and the liquid hourly space velocity (LHSV) of the liquid ammonia at 0.5-2.0 h⁻¹. -1 The LHSV of ethylene glycol is 0.05–0.5 h. -1 The hydrogen space velocity is 300–500 ml / g cat .h;

[0063] Preferably, the application further includes pretreating a hydrogen-nitrogen mixture with a hydrogen content of 5-60 vol% using the catalyst;

[0064] More preferably, the ethylene glycol solution is an aqueous solution of ethylene glycol with an ethylene glycol content of 20-50 wt%.

[0065] Optionally, the reaction temperature can be any value between 120℃, 125℃, 130℃, 135℃, 140℃, 141℃, 143℃, 145℃ and 148℃.

[0066] Using metal oxides as supports and metals as loading materials, along with the introduction of carbon source precursors, aims to utilize the functional groups such as hydroxyl groups on the carbon source precursors to complex the metal, resulting in higher dispersion of the supported metal. This provides more dehydrogenation and hydrogenation sites, thereby promoting the conversion of ethylene glycol. The stepwise impregnation method is used to separately load M1 and M2 to regulate the catalyst's dehydrogenation and hydrogenation capabilities, improving the selectivity of ethylenediamine. The contents of M1, M2, the support, and the carbon source must be within the preferred range of this invention to ensure the catalyst has an appropriate number of dehydrogenation and hydrogenation centers and matching dehydrogenation and hydrogenation capabilities, promoting ethylene glycol conversion and ethylenediamine formation. If the contents of M1 and M2 are too low, the catalyst will have fewer dehydrogenation and hydrogenation centers, which is detrimental to ethylene glycol conversion and ethylenediamine formation. If the contents of M1 and M2 are too high, M1 and M2 will aggregate, reducing the number of dehydrogenation and hydrogenation centers, which is also detrimental to ethylene glycol conversion and ethylenediamine formation. Within the preferred range of the present invention, the carbon source content enables M1 and M2 to have a high degree of dispersion, exposing more dehydrogenation and hydrogenation centers, thus promoting ethylene glycol conversion and ethylenediamine formation. If the carbon source content is too low, the dispersion of M1 and M2 decreases, reducing the exposed hydrogenation and dehydrogenation centers, which is not conducive to ethylene glycol conversion and ethylenediamine formation. If the carbon source content is too high, a large amount of graphite carbon will be generated, covering the hydrogenation and dehydrogenation centers, resulting in a reduction of dehydrogenation and hydrogenation centers, which is not conducive to ethylene glycol conversion and ethylenediamine formation.

[0067] Further optimization of parameters such as the content and concentration of the support, M1, M2, and carbon source can further regulate the catalyst's dehydrogenation and hydrogenation capabilities.

[0068] The beneficial effects of this invention are:

[0069] The catalyst provided by this invention, while ensuring catalytic activity and selectivity, does not contain precious metals, thus greatly reducing costs compared to conventional catalysts of the same type.

[0070] According to the preparation method provided by the present invention, a catalyst with matching dehydrogenation and hydrogenation centers and excellent catalytic performance can be prepared using a simple process and inexpensive and readily available raw materials, which has value for industrial application.

[0071] Using the catalyst provided by this invention, ethylenediamine can be synthesized in one step from ethylene glycol. The process is simple and fundamentally solves the problem of raw material supply for ethylenediamine synthesis. Furthermore, under the action of the catalyst of this invention, the synthesis exhibits higher ethylenediamine selectivity and better stability. Detailed Implementation

[0072] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0073] Example 1

[0074] A supported catalyst was prepared according to the method provided in this invention, and applied to the amination of ethylene glycol to synthesize ethylenediamine. Its conversion and selectivity were measured. The specific steps are as follows:

[0075] S1: Add 4.16g Ni(NO3)2·6H2O and 0.39g glucose to 15ml deionized water to obtain Ni 2+ A concentration of 0.95 mol / L, glucose and Ni 2+ Solution A has a molar ratio of 0.15;

[0076] S2: Add 8.00g of γ-Al2O3 to solution A obtained in S1, so that the content of Ni in the system accounts for 10.5wt% of the content of γ-Al2O3. Then, rotary evaporate at 40℃ for 10h. The resulting solid B is heated to 450℃ at a rate of 0.5℃ / min under nitrogen atmosphere and calcined at 450℃ for 4h to obtain solid C.

[0077] S3: Add 1.06g Cu(NO3)2·6H2O and 0.12g glucose to 10ml deionized water to obtain Cu 2+ A concentration of 0.44 mol / L, glucose and Cu 2+ In solution D with a molar ratio of 0.15, the Cu content accounts for 3.5 wt% of the γ-Al2O3 content, and glucose serves as the carbon source, in which the total carbon content accounts for 2.5 wt% of the γ-Al2O3 content.

[0078] S4: Add the solid C obtained in S2 to the solution D obtained in S3, rotary evaporate at 40℃ for 10h, heat the resulting solid E to 300℃ at a rate of 0.5℃ / min under a nitrogen atmosphere, and calcine at 300℃ for 4h to obtain the supported catalyst.

[0079] S5: The supported catalyst obtained in S4 is crushed into 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, 20wt% ethylene glycol solution, and hydrogen are introduced. The reaction pressure is controlled at 8.0 MPa, the reaction temperature at 148℃, and the liquid hourly space velocity (LHSV) of the liquid ammonia at 0.5 h⁻¹. -1 The LHSV of ethylene glycol liquid air is 0.05 h⁻¹. -1 The hydrogen space velocity is 400 ml / gcat .h

[0080] The conversion rate of ethylene glycol was measured to be 80.3%, and the selectivity of ethylenediamine was 70.5%.

[0081] Example 2

[0082] A supported catalyst was prepared according to the method provided in this invention, and applied to the amination of ethylene glycol to synthesize ethylenediamine. Its conversion and selectivity were measured. The specific steps are as follows:

[0083] S1: Add 8.05g Ni(NO3)2·6H2O and 0.50g glucose to 15ml deionized water to obtain Ni 2+ A concentration of 1.84 mol / L, glucose and Ni 2+ Solution A has a molar ratio of 0.10;

[0084] S2: Add 8.00g of zirconium oxide to solution A obtained in S1, so that the content of Ni in the system accounts for 20.3wt% of the zirconium oxide content. Then, rotary evaporate at 50℃ for 8h. The resulting solid B is heated to 600℃ at a rate of 1℃ / min under nitrogen atmosphere and calcined at 600℃ for 4h to obtain solid C.

[0085] S3: Add 2.36g Cu(NO3)2·6H2O and 0.23g glucose to 10ml deionized water to obtain Cu 2+ A concentration of 0.98 mol / L, glucose and Cu 2+ In solution D with a molar ratio of 0.13, the Cu content accounts for 7.8 wt% of the zirconium oxide content, and glucose serves as the carbon source, with the total carbon content accounting for 3.6 wt% of the zirconium oxide content.

[0086] S4: Add the solid C obtained in S2 to the solution D obtained in S3, rotary evaporate at 50℃ for 10h, heat the resulting solid E to 300℃ at a rate of 1℃ / min under a nitrogen atmosphere, and calcine at 300℃ for 4h to obtain the supported catalyst.

[0087] S5: The supported catalyst obtained in S4 is crushed into 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, 50wt% ethylene glycol solution, and hydrogen are introduced. The reaction pressure is controlled at 10.0 MPa, the reaction temperature at 145℃, and the liquid hourly space velocity (LHSV) of the liquid ammonia at 1.5 h⁻¹. -1 The LHSV of ethylene glycol liquid air is 0.08 h⁻¹. -1 The hydrogen space velocity is 400 ml / g cat .h

[0088] The conversion rate of ethylene glycol was measured to be 80.5%, and the selectivity of ethylenediamine was 80.2%.

[0089] Example 3

[0090] A supported catalyst was prepared according to the method provided in this invention, and applied to the amination of ethylene glycol to synthesize ethylenediamine. Its conversion and selectivity were measured. The specific steps are as follows:

[0091] S1: Add 10.07g Ni(NO3)2·6H2O and 0.81g fructose to 15ml deionized water to obtain Ni 2+ The concentration was 2.31 mol / L, and the fructose and Ni 2+ Solution A has a molar ratio of 0.13;

[0092] S2: Add 8.00g of aluminum hydroxide to solution A obtained in S1, so that the content of Ni in the system accounts for 25.4wt% of the aluminum hydroxide content. Then, rotary evaporate at 60℃ for 6h. The resulting solid B is heated to 550℃ at a rate of 1℃ / min under nitrogen atmosphere and calcined at 550℃ for 4h to obtain solid C.

[0093] S3: Add 1.60g Cu(NO3)2·6H2O and 0.16g fructose to 10ml deionized water to obtain Cu 2+ A concentration of 0.66 mol / L, fructose and Cu 2+ In solution D with a molar ratio of 0.13, the Cu content accounts for 5.3 wt% of the aluminum hydroxide content, and fructose, as a carbon source, accounts for 4.8 wt% of the total carbon content of the aluminum hydroxide.

[0094] S4: Add the solid C obtained in S2 to the solution D obtained in S3, rotary evaporate at 60℃ for 6h, heat the resulting solid E to 250℃ at a rate of 1℃ / min under a nitrogen atmosphere, and calcine at 250℃ for 4h to obtain the supported catalyst.

[0095] S5: The supported catalyst obtained in S4 is crushed into 20-40 mesh and loaded into a fixed-bed reactor. Under a hydrogen-nitrogen mixed atmosphere with a hydrogen content of 40 wt%, liquid ammonia, 50 wt% ethylene glycol solution, and hydrogen are introduced. The reaction pressure is controlled at 10.0 MPa, the reaction temperature at 145℃, and the liquid hourly space velocity (LHSV) of liquid ammonia at 1.5 h⁻¹. -1 The LHSV of ethylene glycol liquid air is 0.08 h⁻¹. -1 The hydrogen space velocity is 400 ml / g cat .h

[0096] The conversion rate of ethylene glycol was measured to be 75.4%, and the selectivity of ethylenediamine was 84.5%.

[0097] Example 4

[0098] A supported catalyst was prepared according to the method provided in this invention, and applied to the amination of ethylene glycol to synthesize ethylenediamine. Its conversion and selectivity were measured. The specific steps are as follows:

[0099] S1: Add 6.54g Ni(NO3)2·6H2O and 0.41g fructose to 15ml deionized water to obtain Ni 2+ A concentration of 1.50 mol / L, fructose and Ni 2+ Solution A has a molar ratio of 0.10;

[0100] S2: Add 8.00g of cerium oxide to solution A obtained in S1, so that the content of Ni in the system accounts for 16.5wt% of the cerium oxide content. Then, rotary evaporate at 50℃ for 12h. The resulting solid B is heated to 500℃ at a rate of 1℃ / min under nitrogen atmosphere and calcined at 500℃ for 4h to obtain solid C.

[0101] S3: Add 2.66g Fe(NO3)2·9H2O and 0.12g fructose to 10ml deionized water to obtain Fe 3+ A concentration of 0.66 mol / L, fructose and Fe 3+ In solution D with a molar ratio of 0.10, the Fe content accounts for 4.6 wt% of the cerium oxide content, and fructose, as a carbon source, accounts for 2.6 wt% of the total carbon content of the cerium oxide content.

[0102] S4: Add the solid C obtained in S2 to the solution D obtained in S3, rotary evaporate at 50℃ for 10h, heat the resulting solid E to 300℃ at a rate of 1℃ / min under a nitrogen atmosphere, and calcine at 300℃ for 4h to obtain the supported catalyst.

[0103] S5: The supported catalyst obtained in S4 is crushed into 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, 30wt% ethylene glycol solution, and hydrogen are introduced. The reaction pressure is controlled at 10.0 MPa, the reaction temperature at 135℃, and the liquid hourly space velocity (LHSV) of the liquid ammonia at 2.0 h⁻¹. -1 The LHSV of ethylene glycol liquid air is 0.10 h⁻¹. -1 The hydrogen space velocity is 400 ml / g cat .h

[0104] The conversion rate of ethylene glycol was measured to be 90.3%, and the selectivity of ethylenediamine was 73.2%.

[0105] Example 5

[0106] A supported catalyst was prepared according to the method provided in this invention, and applied to the amination of ethylene glycol to synthesize ethylenediamine. Its conversion and selectivity were measured. The specific steps are as follows:

[0107] S1: Add 7.25g Co(NO3)2·6H2O and 0.67g glucose to 15ml deionized water to obtain Co 2+ A concentration of 1.66 mol / L, glucose and Co 2+ Solution A has a molar ratio of 0.15;

[0108] S2: Add 8.00g of γ-Al2O3 to solution A obtained in S1, so that the content of Co in the system accounts for 18.3wt% of the content of γ-Al2O3. Then, rotary evaporate at 60℃ for 8h. The resulting solid B is heated to 500℃ at a rate of 1℃ / min under nitrogen atmosphere and calcined at 500℃ for 4h to obtain solid C.

[0109] S3: Add 1.94g Cu(NO3)2·6H2O and 0.22g glucose to 10ml deionized water to obtain Cu 2+ A concentration of 0.80 mol / L, glucose and Cu 2+ In solution D with a molar ratio of 0.15, the content of Co in the system accounts for 6.4 wt% of the content of γ-Al2O3, and the total carbon content of glucose as a carbon source accounts for 4.4 wt% of the content of γ-Al2O3.

[0110] S4: Add the solid C obtained in S2 to the solution D obtained in S3, and rotary evaporate at 60℃ for 8 hours. Heat the resulting solid E to 250℃ at a rate of 1℃ / min under a nitrogen atmosphere, and calcine at 250℃ for 4 hours to obtain the supported catalyst.

[0111] S5: The supported catalyst obtained in S4 is crushed into 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, 20wt% ethylene glycol solution, and hydrogen are introduced. The reaction pressure is controlled at 12.0 MPa, the reaction temperature at 130℃, and the liquid hourly space velocity (LHSV) of the liquid ammonia at 2.0 h⁻¹. -1 The LHSV of ethylene glycol liquid air is 0.08 h⁻¹. -1 The hydrogen space velocity is 400 ml / g cat .h

[0112] The conversion rate of ethylene glycol was measured to be 78.2%, and the selectivity of ethylenediamine was 79.1%.

[0113] Example 6

[0114] A supported catalyst was prepared according to the method provided in this invention, and applied to the amination of ethylene glycol to synthesize ethylenediamine. Its conversion and selectivity were measured. The specific steps are as follows:

[0115] S1: Add 9.20g Co(NO3)2·6H2O and 1.62g soluble starch to 15ml deionized water to obtain Co 2+A concentration of 2.11 mol / L, soluble starch and Co 2+ Solution A has a molar ratio of 0.15;

[0116] S2: Add 8.00g of zirconium oxide to solution A obtained in S1, so that the content of Co in the system accounts for 23.2wt% of the zirconium oxide content. Then, rotary evaporate at 60℃ for 8h. The resulting solid B is heated to 500℃ at a rate of 1℃ / min under nitrogen atmosphere and calcined at 500℃ for 4h to obtain solid C.

[0117] S3: Add 0.76g Cu(NO3)2·6H2O and 0.16g soluble starch to 10ml deionized water to obtain Cu 2+ A concentration of 0.31 mol / L, soluble starch and Cu 2+ In solution D with a molar ratio of 0.15, the Cu content accounts for 2.5 wt% of the zirconium oxide content, and the total carbon content of the soluble starch as a carbon source accounts for 4.7 wt% of the zirconium oxide content.

[0118] S4: Add the solid C obtained in S2 to the solution D obtained in S3, and rotary evaporate at 60℃ for 8 hours. Heat the resulting solid E to 250℃ at a rate of 1℃ / min under a nitrogen atmosphere, and calcine at 250℃ for 4 hours to obtain the supported catalyst.

[0119] S5: The supported catalyst obtained in S4 is crushed into 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, 20wt% ethylene glycol solution, and hydrogen are introduced. The reaction pressure is controlled at 12.0 MPa, the reaction temperature at 145℃, and the liquid hourly space velocity (LHSV) of liquid ammonia at 1.60 h⁻¹. -1 The LHSV of ethylene glycol liquid air is 0.08 h⁻¹. -1 The hydrogen space velocity is 400 ml / g cat .h

[0120] The conversion rate of ethylene glycol was measured to be 81.7%, and the selectivity of ethylenediamine was 78.5%.

[0121] Example 7

[0122] A supported catalyst was prepared according to the method provided in this invention, and applied to the amination of ethylene glycol to synthesize ethylenediamine. Its conversion and selectivity were measured. The specific steps are as follows:

[0123] S1: Add 2.70g Co(NO3)2·6H2O and 0.47g glucose to 15ml deionized water to obtain Co 2+ A concentration of 0.62 mol / L, glucose and Co 2+ Solution A has a molar ratio of 0.28;

[0124] S2: Add 8.00g of aluminum hydroxide to solution A obtained in S1, so that the content of Co in the system accounts for 6.8wt% of the aluminum hydroxide content. Then, rotary evaporate at 60℃ for 8h. The resulting solid B is heated to 450℃ at a rate of 1℃ / min under nitrogen atmosphere and calcined for 4h to obtain solid C.

[0125] S3: Add 1.64g Zn(NO3)2·6H2O and 0.28g glucose to 10ml deionized water to obtain Zn 2+ A concentration of 0.55 mol / L, glucose and Zn 2+ In solution D with a molar ratio of 0.28, the Zn content accounts for 4.5 wt% of the aluminum hydroxide content, and glucose serves as the carbon source, with the total carbon content accounting for 3.7 wt% of the aluminum hydroxide content.

[0126] S4: Add the solid C obtained in S2 to the solution D obtained in S3, rotary evaporate at 60℃ for 8h, and heat the resulting solid E to 300℃ at a rate of 1℃ / min under a nitrogen atmosphere and calcine for 4h to obtain the supported catalyst.

[0127] S5: The supported catalyst obtained in S4 is crushed into 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, 20wt% ethylene glycol solution, and hydrogen are introduced. The reaction pressure is controlled at 12.0 MPa, the reaction temperature at 145℃, and the liquid hourly space velocity (LHSV) of liquid ammonia at 1.0 h⁻¹. -1 The LHSV of ethylene glycol liquid air is 0.05 h⁻¹. -1 The hydrogen space velocity is 400 ml / g cat .h

[0128] The conversion rate of ethylene glycol was measured to be 88.9%, and the selectivity of ethylenediamine was 69.3%.

[0129] Example 8

[0130] A supported catalyst was prepared according to the method provided in this invention, and applied to the amination of ethylene glycol to synthesize ethylenediamine. Its conversion and selectivity were measured. The specific steps are as follows:

[0131] S1: Add 3.53g Co(NO3)2·6H2O and 0.68g glucose to 15ml deionized water to obtain Co 2+ A concentration of 0.81 mol / L, glucose and Co 2+ Solution A has a molar ratio of 0.31;

[0132] S2: Add 8.00g of cerium oxide to solution A obtained in S1, so that the content of Co in the system accounts for 8.9wt% of the cerium oxide content. Then, rotary evaporate at 60℃ for 8h. The resulting solid B is heated to 450℃ at a rate of 1℃ / min under nitrogen atmosphere and calcined for 4h to obtain solid C.

[0133] S3: Add 1.91g Fe(NO3)2·9H2O and 0.26g glucose to 10ml deionized water to obtain Fe 3+ A concentration of 0.47 mol / L, glucose and Fe 3+ In solution D with a molar ratio of 0.31, the Fe content accounts for 3.3 wt% of the cerium oxide content, and glucose serves as the carbon source, in which the total carbon content accounts for 4.7 wt% of the cerium oxide content.

[0134] S4: Add the solid C obtained in S2 to the solution D obtained in S3, rotary evaporate at 60℃ for 8h, and heat the resulting solid E to 300℃ at a rate of 1℃ / min under a nitrogen atmosphere and calcine for 4h to obtain the supported catalyst.

[0135] S5: The supported catalyst obtained in S4 is crushed into 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, 20wt% ethylene glycol solution, and hydrogen are introduced. The reaction pressure is controlled at 12.0 MPa, the reaction temperature at 145℃, and the liquid hourly space velocity (LHSV) of liquid ammonia at 0.50 h⁻¹. -1 The LHSV of ethylene glycol liquid air is 0.03 h⁻¹. -1 The hydrogen space velocity is 400 ml / g cat .h

[0136] The conversion rate of ethylene glycol was measured to be 75.3%, and the selectivity of ethylenediamine was 76.9%.

[0137] Comparative Example 1

[0138] The difference from Example 8 is that no carbon source was added during the preparation process of Comparative Example 1. The catalyst with the same Co and Fe content but without carbon source was prepared only according to the catalyst preparation process in Example 8. The obtained catalyst was evaluated according to the evaluation conditions of Example 8. The ethylene glycol conversion rate was measured to be 29.5% and the ethylenediamine selectivity was 56.5%, which was significantly lower than the catalyst performance in Example 8.

[0139] Because the functional groups such as hydroxyl groups on the carbon source precursor can complex metals, improve metal dispersion, and increase dehydrogenation and hydrogenation sites, they are beneficial to the conversion of ethylene glycol. Compared with Example 8, Comparative Example 1 suffers from a decrease in Co and Fe dispersion and a reduction in hydrogenation and dehydrogenation centers due to the absence of a carbon source precursor during catalyst preparation, resulting in a significant decrease in ethylene glycol conversion and ethylenediamine selectivity.

[0140] Please note that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. The above embodiments only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for preparing a supported catalyst, characterized in that, Includes the following steps: S1: Dissolve the M1 precursor and the carbon source precursor in water to obtain solution A; the M1 precursor includes one or more of cobalt nitrate, cobalt acetate, nickel nitrate, and nickel acetate; the molar ratio of the carbon source precursor to the metal ions in the M1 precursor is 0.10 to 0.40:1; S2: Add a support to solution A obtained in S1, such that the content of metal elements in the precursor M1 accounts for 5-30 wt% of the support, and perform a first rotary evaporation to obtain solid B. Then, subject solid B to a first heat treatment under an inert atmosphere to obtain solid C. The support includes one or more of alumina, aluminum hydroxide, zirconium oxide, zirconium hydroxide, silicon oxide, and cerium oxide. S3: Dissolve the M2 precursor and the carbon source precursor in water to obtain solution D; the M2 precursor includes one or more of copper nitrate, ferric nitrate, manganese nitrate, and ammonium molybdate; the molar ratio of the carbon source precursor to the metal ions in the M2 precursor is 0.10 to 0.40:1; The metal element content in the M2 precursor accounts for 1-10 wt% of the carrier. S4: Add solid C obtained from S2 to solution D obtained from S3 and perform a second rotary evaporation to obtain solid E. Then, subject solid E to a second heat treatment under an inert atmosphere to obtain the final product. The carbon source precursors mentioned in steps S1 and S3 include one or more of glucose, fructose, starch, and cyclodextrin; the total carbon content in the carbon source precursor accounts for 1 to 6 wt% of the carrier.

2. The preparation method according to claim 1, characterized in that, The concentration of M1 ions in solution A is 0.5–3.5 mol / L.

3. The preparation method according to claim 1, characterized in that, Step S2 satisfies one or more of the following conditions: a. The temperature of the first rotary evaporation is 40–70°C, and the time is 4–12 hours; b. The heating rate of the first heat treatment is 0.5–1 °C / min; c. The target temperature for the first heat treatment is 350–600℃, and the holding time is 4–6 hours.

4. The preparation method according to claim 1, characterized in that, The concentration of M2 ions in solution D is 0.1–1.2 mol / L.

5. The preparation method according to claim 1, characterized in that, Step S4 satisfies one or more of the following conditions: d. The temperature of the second rotary evaporation is 40–70°C, and the time is 4–12 hours; e. The heating rate for the second heat treatment is 0.5–1 °C / min; f. The target temperature for the second heat treatment is 200–350°C, and the holding time is 4–6 hours.

6. The preparation method according to any one of claims 1-5, characterized in that, The preparation method also satisfies one or more of the following conditions: g. The molar ratio of the carbon source precursor in step S1 to the metal ions in the M1 precursor is 0.10 to 0.35:1; h. The concentration of M1 in solution A is 0.6–2.5 mol / L; i. The molar ratio of the carbon source precursor to the metal ions in the M2 precursor in step S3 is 0.10 to 0.35:1; j. The ion concentration of M2 in solution D is 0.3–1.0 mol / L; k. The total carbon content in the carbon source precursor accounts for 2-5 wt% of the carrier; 1. The target temperature for the first heat treatment is 400–500°C; m. The target temperature for the second heat treatment is 250–300 °C.

7. The application of a supported catalyst prepared by the method according to any one of claims 1-6, characterized in that, It is used in the amination of ethylene glycol to synthesize ethylenediamine, and the specific application conditions are as follows: The catalyst was crushed to 20-40 mesh and loaded into a fixed-bed reactor. Liquid ammonia, ethylene glycol solution, and hydrogen were introduced. The reaction pressure was controlled at 6.0-12.0 MPa, the reaction temperature at 120-148°C, and the liquid hourly space velocity (LHSV) of the liquid ammonia at 0.5-2.0 h⁻¹. -1 The LHSV of ethylene glycol is 0.05–0.5 h. -1 The hydrogen space velocity is 300–500 ml / g cat .h 8. The application according to claim 7, characterized in that, The ethylene glycol solution is an aqueous solution of ethylene glycol with a content of 20-50 wt%.