A catalyst for preparing gamma-butyrolactone by dehydrogenating 1,4-butanediol, and a preparation method and application thereof

Abstract

The application discloses a catalyst for preparing gamma-butyrolactone by dehydrogenating 1,4-butanediol, which is composed of a carrier, an active component and an auxiliary agent supported on the carrier, and the content of the active component and the auxiliary agent is as follows: the active component is 15-30% and the auxiliary agent is 0.5-3% by weight of the carrier; the active component is Cu and Ce, the auxiliary agent is at least one of K, Mg, Mn and Zr, and the carrier is a carbon carrier. Meanwhile, the application also discloses a preparation method and application of the catalyst. When the catalyst is used for preparing gamma-butyrolactone by dehydrogenating 1,4-butanediol, the raw material conversion rate is high, the selectivity of the target product is high, and the catalytic activity of the catalyst is good.

Description

Technical Field

[0001] This invention belongs to the field of γ-butyrolactone preparation technology, specifically relating to a catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, its preparation method and application. Background Technology

[0002] γ-Butyrolactones are important organic compounds and intermediates, characterized by high solubility, good stability, low toxicity, and excellent electrical conductivity. They and their derivatives are widely used in petrochemical, textile, pharmaceutical, pesticide, and fragrance industries. They can be used to produce pharmaceuticals such as cyclopropylamine and pyrrolidone, and also as industrial solvents, diluents, and curing agents. In recent years, with the rapid development of the fine chemical, pharmaceutical, and biodegradable plastics industries, especially the development of new energy vehicle power batteries and super energy storage batteries, the demand for γ-butyrolactones has been increasing year by year. The main synthetic methods for γ-butyrolactones are the maleic anhydride hydrogenation method and the 1,4-butanediol dehydrogenation method. The latter, due to its advantages in raw material and product separation, has become the mainstream industrial production method for γ-butyrolactones.

[0003] Chinese patent CN1687045A discloses a CuO-Cr2O3 / SiO2 catalyst synthesized using the sol-gel method, which catalyzes the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone. This catalyst achieves a 100% single-pass conversion and a 99% selectivity for γ-butyrolactone. However, this catalyst contains highly toxic Cr, causing significant pollution. CN1562473A discloses a Cu-Zn-Ce catalyst prepared using an alkaline precipitant precipitation method, with a copper oxide mass percentage of 48-55%. This catalyst achieves a 98% conversion of 1,4-butanediol and a γ-butyrolactone selectivity close to 95%. Chinese patent CN103877981A discloses a CuO-ZnO / Al2O3-SiO2 catalyst prepared using polyethylene glycol polymerization and co-precipitation methods. This catalyst catalyzes the atmospheric pressure gas-phase dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, achieving a 99% conversion of 1,4-butanediol and a 96.5% selectivity for γ-butyrolactone. In summary, existing publicly available catalysts mainly employ co-precipitation and other catalyst preparation methods, which involve lengthy processes and high water consumption. Therefore, there is a need to develop a catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone that is simple to prepare, highly active, has low content of active components, and is non-toxic and pollution-free. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, its preparation method, and its application. The catalyst has a short preparation process, is environmentally friendly, and exhibits good catalytic activity.

[0005] A catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, the catalyst comprising a support, an active component supported on the support, and an auxiliary agent, wherein the contents of the active component and the auxiliary agent, by weight percentage of the support, are as follows: active component 15-30%, auxiliary agent 0.5-3%; the active component is Cu and Ce, the auxiliary agent is at least one selected from K, Mg, Mn, and Zr, and the support is a carbon support.

[0006] Preferably, the mass ratio of Cu to Ce is (2-8):1.

[0007] Preferably, the carrier is any one of activated carbon, carbon nanotubes, and graphene.

[0008] Preferably, the specific surface area of ​​the carrier is greater than 200 m². 2 / g.

[0009] The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone includes the following steps:

[0010] (1) Add the carbon support to the nitric acid solution, heat and reflux at 70-150℃ for 3-14h, filter, wash with deionized water until neutral, dry, and grind;

[0011] (2) Dissolve the metal salts corresponding to the active components and auxiliaries in water or ethanol to obtain a mixed metal solution;

[0012] (3) Add the carrier obtained in step (1) to the metal mixture solution, stir at room temperature until dry, then dry, calcine, grind, and press into tablets to obtain the catalyst.

[0013] Preferably, the tablets are compressed to 20-60 mesh.

[0014] Preferably, the concentration of the nitric acid solution is 5-10 mol / L, and the ratio of the carbon support to the nitric acid solution is 1 g: (10-20) mL.

[0015] Preferably, in the metal mixed solution, the total metal concentration of Cu, Ce, and the additive is 0.5-2 mol / L; the metal salt corresponding to the active metal is a nitrate, chloride, or acetate; and the metal salt corresponding to the additive is a nitrate or chloride.

[0016] Preferably, the drying in step (1) is performed at 80-120℃ for 8-12 hours; the drying in step (2) is performed at 60-100℃ for 8-12 hours; and the calcination is performed at 280-380℃ for 3-5 hours.

[0017] A method for catalytic dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone is as follows: The catalyst described in this invention is loaded into a fixed-bed reactor, a first hydrogen-containing gas is introduced for reduction activation, then the reaction temperature is adjusted to 190-260℃, a second hydrogen-containing gas is introduced, and the 1,4-butanediol feedstock solution is introduced at a reaction temperature of 1-4 h. -1 After being vaporized at 100-180℃, the gas is carried into a fixed-bed reactor by the second hydrogen-containing gas and dehydrogenation reaction is carried out at atmospheric pressure to 0.5MPa. The hydrogen-to-ethanol molar ratio during the dehydrogenation reaction is 5-20.

[0018] Wherein, the first hydrogen-containing gas is 100% hydrogen, or is composed of hydrogen with a volume percentage of ≥5% and a balance gas; the second hydrogen-containing gas is 100% hydrogen, or is composed of hydrogen with a volume percentage of ≥60% and a balance gas; the balance gas is nitrogen, helium or argon.

[0019] Preferably, the reduction activation conditions are: reduction temperature 200-350℃, reduction time 3-8h, reduction pressure at atmospheric pressure, and the space velocity of the first hydrogen-containing gas 500-5000h⁻¹. -1 .

[0020] Advantages of this invention:

[0021] (1) The catalyst provided by the present invention has a high feed conversion rate, high target product selectivity and good catalytic activity when used for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone.

[0022] (2) The catalyst preparation process provided by the present invention is short, environmentally friendly, and easy to scale up industrially. Detailed Implementation

[0023] Example 1

[0024] 1. A catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, said catalyst comprising an activated carbon support (AC), an active component supported on said support, and an auxiliary agent, wherein the contents of the active component and the auxiliary agent, by weight ratio of said support, are as follows: active component 30%, auxiliary agent 3%; said active component is Cu and Ce in a mass ratio of 2:1, said auxiliary agent is K and Mn in an equal mass ratio, and said support has a specific surface area of ​​1060 m². 2 / g.

[0025] 2. The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone includes the following steps:

[0026] (1) Add the carrier to a 5 mol / L nitric acid solution at a ratio of 1 g: 10 mL, and incubate at 150 °C.

[0027] Heat under reflux for 3 hours, filter, wash with deionized water until neutral, dry at 80℃ for 12 hours, and grind.

[0028] (2) Dissolve copper nitrate, cerium nitrate, potassium acetate and manganese nitrate in ethanol to obtain a metal mixed solution with a total ion concentration of 0.5 mol / L for copper, cerium, potassium and manganese.

[0029] (3) Add the carrier obtained in step (1) to the metal mixed solution, stir until dry at room temperature, then dry at 60°C for 12 hours, calcine at 280°C for 5 hours, grind, and press into tablets to 20-40 mesh to obtain the catalyst.

[0030] Example 2

[0031] 1. A catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, said catalyst comprising a graphene support, an active component supported on the support, and an auxiliary agent, wherein the contents of the active component and the auxiliary agent, by weight ratio of the support, are as follows: active component 15%, auxiliary agent 1.5%; the active component is Cu and Ce in a mass ratio of 8:1, the auxiliary agent is K and Zr in a mass ratio of 4:1, and the specific surface area of ​​the support is 740 m². 2 / g.

[0032] 2. The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone includes the following steps:

[0033] (1) Add the carrier to a 10 mol / L nitric acid solution at a ratio of 1 g: 10 mL, and incubate at 70 °C.

[0034] Heat under reflux for 14 hours, filter, wash with deionized water until neutral, dry at 100℃ for 8 hours, and grind.

[0035] (2) Dissolve copper acetate, cerium chloride, potassium nitrate and zirconium nitrate in water to obtain a metal mixed solution with a total ion concentration of 2 mol / L for copper, cerium, potassium and zirconium;

[0036] (3) Add the carrier obtained in step (1) to the metal mixed solution, stir until dry at room temperature, then dry at 100°C for 8 hours, calcine at 380°C for 3 hours, grind, and press into tablets to 40-60 mesh to obtain the catalyst.

[0037] Example 3

[0038] 1. A catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, said catalyst comprising a supported carbon nanotubes (CNTs), an active component supported on said support, and an auxiliary agent, wherein the contents of the active component and the auxiliary agent, by weight ratio of said support, are as follows: active component 20%, auxiliary agent 0.5%; said active component is Cu and Ce in a mass ratio of 4:1, said auxiliary agent is Mn, and said support has a specific surface area of ​​280 m². 2 / g.

[0039] 2. The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone includes the following steps:

[0040] (1) Add the carrier to an 8 mol / L nitric acid solution at a ratio of 1 g: 15 mL, and incubate at 150 °C.

[0041] Heat under reflux for 10 hours, filter, wash with deionized water until neutral, dry at 80℃ for 10 hours, and grind.

[0042] (2) Dissolve copper chloride, cerium acetate and manganese chloride in water to obtain a mixed metal solution with a total ion concentration of 1 mol / L for copper, cerium and manganese.

[0043] (3) Add the carrier obtained in step (1) to the metal mixed solution, stir until dry at room temperature, then dry at 80°C for 10 hours, calcine at 350°C for 4 hours, grind, and press into tablets to 20-60 mesh to obtain the catalyst.

[0044] Example 4

[0045] 1. A catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, said catalyst comprising a graphene support, an active component supported on the support, and an auxiliary agent, wherein the contents of the active component and the auxiliary agent, by weight ratio of the support, are as follows: active component 26%, auxiliary agent 2.5%; the active component is Cu and Ce in a mass ratio of 6:1, the auxiliary agent is Mn and Zr, and the specific surface area of ​​the support is 740 m². 2 / g.

[0046] 2. The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone includes the following steps:

[0047] (1) Add the carrier to a 7 mol / L nitric acid solution at a ratio of 1 g: 20 mL, and incubate at 150 °C.

[0048] Heat under reflux for 12 hours, filter, wash with deionized water until neutral, dry at 90℃ for 11 hours, and grind.

[0049] (2) Dissolve copper chloride, cerium acetate, manganese nitrate and zirconium nitrate in ethanol to obtain a metal mixed solution with a total ion concentration of 1.5 mol / L for copper, cerium, manganese and zirconium;

[0050] (3) Add the carrier obtained in step (1) to the metal mixed solution, stir until dry at room temperature, then dry at 75°C for 11 hours, calcine at 300°C for 3.5 hours, grind, and press into tablets to 20-40 mesh to obtain the catalyst.

[0051] Example 5

[0052] 1. A catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, said catalyst comprising an activated carbon support (AC), an active component supported on said support, and an auxiliary agent, wherein the contents of the active component and the auxiliary agent, by weight ratio of said support, are as follows: active component 20%, auxiliary agent 2%; said active component is Cu and Ce in a mass ratio of 6:1, said auxiliary agent is Mg, and said support has a specific surface area of ​​1060 m². 2 / g.

[0053] 2. In the preparation, magnesium salt is magnesium chloride, and the rest is the same as in Example 1.

[0054] Example 6

[0055] The method for preparing γ-butyrolactone by catalytic dehydrogenation of 1,4-butanediol using the catalyst provided by this invention is as follows: The catalyst is loaded into a fixed-bed reactor, and a first hydrogen-containing gas is introduced for reduction activation. The reduction temperature is 200-350℃, the reduction time is 3-8 hours, the reduction pressure is atmospheric pressure, and the space velocity of the first hydrogen-containing gas is 5000 h⁻¹. -1 Then adjust the reaction temperature to 190-260℃, introduce the second hydrogen-containing gas, and add the 1,4-butanediol feedstock solution over 1-4 hours. -1 After being vaporized at 100-180℃, the gas is carried into a fixed-bed reactor by the second hydrogen-containing gas and dehydrogenation reaction is carried out at atmospheric pressure to 0.5MPa. The hydrogen-to-ethanol molar ratio during the dehydrogenation reaction is 5-20.

[0056] Wherein, the first hydrogen-containing gas is 100% hydrogen, or is composed of hydrogen with a volume percentage of ≥5% and a balance gas; the second hydrogen-containing gas is 100% hydrogen, or is composed of hydrogen with a volume percentage of ≥60% and a balance gas; the balance gas is nitrogen, helium or argon.

[0057] The products were analyzed by gas chromatography online after 2 hours of reaction. The reaction conditions and results are shown in Table 1.

[0058] Table 1 Reaction conditions and results

[0059] .

Claims

1. A catalyst for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone, characterized in that: The catalyst is composed of a support, an active component supported on the support, and an auxiliary agent. The contents of the active component and the auxiliary agent, based on the weight ratio of the support, are as follows: active component 15-30%, auxiliary agent 0.5-3%; the active component is Cu and Ce, the auxiliary agent is at least one of K, Mg, Mn, and Zr, and the support is a carbon support; the mass ratio of Cu to Ce is (2-8):

1.

2. The catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone according to claim 1, characterized in that: The carrier can be any one of activated carbon, carbon nanotubes, or graphene.

3. The catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone according to claim 2, characterized in that: The specific surface area of ​​the carrier is greater than 200 m². 2 / g.

4. The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone as described in claim 1, characterized in that: Includes the following steps: (1) Add the carbon support to the nitric acid solution, heat and reflux at 70-150℃ for 3-14h, filter, wash with deionized water until neutral, dry, and grind; (2) Dissolve the metal salts corresponding to the active components and auxiliaries in water or ethanol to obtain a mixed metal solution; (3) Add the carrier obtained in step (1) to the metal mixture solution, stir at room temperature until dry, then dry, calcine, grind, and press into tablets to obtain the catalyst.

5. The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone according to claim 4, characterized in that: The concentration of the nitric acid solution is 5-10 mol / L, and the ratio of the carbon support to the nitric acid solution is 1 g: (10-20) mL.

6. The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone according to claim 5, characterized in that: In the metal mixed solution, the total metal concentration of Cu, Ce, and the additive is 0.5-2 mol / L; the metal salt corresponding to the active component is a nitrate, chloride, or acetate; and the metal salt corresponding to the additive is a nitrate or chloride.

7. The method for preparing the catalyst for the dehydrogenation of 1,4-butanediol to γ-butyrolactone according to claim 6, characterized in that: The drying in step (1) is to dry at 80-120℃ for 8-12 hours; the drying in step (3) is to dry at 60-100℃ for 8-12 hours; the calcination is to calcinate at 280-380℃ for 3-5 hours.

8. A method for preparing γ-butyrolactone by catalytic dehydrogenation of 1,4-butanediol, characterized in that: Specifically, the catalyst is loaded into a fixed-bed reactor, and a first hydrogen-containing gas is introduced for reduction and activation. Then, the reaction temperature is adjusted to 190-260℃, and a second hydrogen-containing gas is introduced. The feed liquid, 1,4-butanediol, is introduced at a rate of 1-4 h. -1 After being vaporized at 100-180℃, the gas is carried into a fixed-bed reactor by the second hydrogen-containing gas and dehydrogenation reaction is carried out at atmospheric pressure to 0.5MPa. The hydrogen-to-ethanol molar ratio during the dehydrogenation reaction is 5-20. Wherein, the catalyst is the catalyst according to claim 1; The first hydrogen-containing gas is 100% hydrogen, or is composed of hydrogen with a volume percentage of ≥5% and a balance gas; the second hydrogen-containing gas is 100% hydrogen, or is composed of hydrogen with a volume percentage of ≥60% and a balance gas; the balance gas is nitrogen, helium or argon.

9. The method for preparing γ-butyrolactone by catalytic dehydrogenation of 1,4-butanediol according to claim 8, characterized in that: The reduction activation conditions are as follows: reduction temperature 200-350℃, reduction time 3-8h, reduction pressure at atmospheric pressure, and space velocity of the first hydrogen-containing gas 500-5000h⁻¹. -1 .