Carbon-modified alumina microsphere supported catalyst, its preparation method and application

Abstract

The application discloses a carbon-modified alumina microsphere loaded catalyst and a preparation method and application thereof. The catalyst comprises a carbon-modified alumina microsphere composite carrier and an active component loaded on the composite carrier. The preparation method of the catalyst comprises the following steps: alumina microspheres are added into a solution of a nitrogen-containing polymer, and then a solvothermal reaction is carried out, and post-treatment is performed, so as to obtain a nitrogen-containing polymer modified alumina microsphere composite carrier; the nitrogen-containing polymer modified alumina microsphere composite carrier is calcined in an inert atmosphere, so as to obtain a carbon-modified alumina microsphere composite carrier; the carbon-modified alumina microsphere composite carrier is immersed into a solution of an active component precursor, taken out, dried, and calcined, so as to obtain the carbon-modified alumina microsphere loaded catalyst. The carbon-modified alumina microsphere catalyst has a higher external surface area, a high utilization rate of the active component, and high catalytic reaction activity.

Description

Technical Field

[0001] This invention relates to the field of industrial catalyst technology, and more specifically, to a catalyst supported on carbon-modified alumina microspheres, its preparation method, and its application. Background Technology

[0002] Alumina-supported catalysts are widely used in petrochemical plants. Industrial alumina supports are generally processed into sheets, strips, spheres, etc. Among them, spherical alumina can be uniformly stacked in a fixed bed in a point-contact manner, reducing column or bed resistance, and therefore has been widely used.

[0003] Currently, commonly used methods for preparing γ-alumina microspheres include oil column molding and spray drying. However, traditional methods for preparing alumina microspheres have poor controllability and can generally only produce alumina microspheres with particle sizes below 100 μm or above 1000 μm. Moreover, the resulting microspheres suffer from problems such as uneven particle size distribution and low sphericity.

[0004] Microfluidics, centered on microstructured components, enhances mixing and transport within confined spaces by reducing the dispersion scale, resulting in a controllable and efficient process. Microchannels are widely used in droplet fabrication, producing droplets with uniform and controllable sizes. Combined with curing initiation methods such as ultraviolet light and temperature, microspheres can be further obtained.

[0005] However, the production capacity of a single microchannel is very low. Taking the preparation of alumina microspheres using a coaxial loop microchannel as an example, the yield is only 1 g / h, which cannot meet the needs of industrial applications. Multi-channel microchannel reactors can solve the problem of production efficiency. Taking an 8-channel reactor as an example, the continuous phase fluid and the dispersed phase fluid flow through a dendritic fluid distributor and are dispersed into 8 independent fluid streams. These streams then flow into 8 identical T-shaped channels to complete the shearing process of the dispersed phase and generate droplets. The droplets generated in each channel eventually converge at the central outlet and flow out. After flowing through a hot oil bath, the droplets solidify into gel microspheres, which are then dried and calcined to obtain alumina microspheres.

[0006] Alumina microspheres obtained using a microchannel reactor can be further processed into supported catalysts, which retain the size and pore characteristics of the alumina microspheres and exhibit unique catalytic reaction performance.

[0007] n-Butanol is an important chemical raw material, mainly used in the manufacture of phthalates, aliphatic diesters, and phosphate plasticizers. It is also used as a solvent, dehydrating agent, demulsifier, and extractant for oils, fragrances, antibiotics, hormones, vitamins, etc. It is an additive for alkyd resin coatings, a cosolvent for nitrocellulose lacquer, a defoamer, and a mineral processing agent. It has a wide range of industrial applications and broad market prospects.

[0008] n-Butanol is obtained by liquid-phase hydrogenation of n-butyraldehyde. When using existing catalysts supported on alumina microspheres for hydrogenation, the content of n-butyl ether in the product is relatively high. When it accumulates to a certain extent, it not only increases the energy consumption for separation, but also affects the quality of the final product due to the difficulty in separation.

[0009] Therefore, it is of great significance to develop a catalyst supported on alumina microspheres with better catalytic reaction performance. Summary of the Invention

[0010] To address the problems in existing technologies, this invention proposes a catalyst supported on carbon-modified alumina microspheres, its preparation method, and its application. The carbon-modified alumina microsphere catalyst of this invention utilizes monodisperse alumina microspheres prepared in a microchannel reactor. These microspheres exhibit a narrow particle size distribution, which facilitates uniform material distribution within the reactor, avoids hot spots, and reduces catalyst particle wear. Furthermore, the catalyst of this invention undergoes carbon modification on the surface of the alumina microspheres. This carbon modification reduces surface acidity, helping to avoid byproducts generated by acid catalysis and improving reaction selectivity.

[0011] One objective of this invention is to provide a catalyst supported on carbon-modified alumina microspheres, wherein the carbon-modified alumina microsphere supported catalyst comprises a carbon-modified alumina microsphere composite support and an active component supported on the composite support;

[0012] Based on the weight of the composite carrier as 100%,

[0013] The carbon content is 0.01–10 wt%; for example, it can be 0.01 wt%, 0.05 wt%, 0.1 wt%, 0.3 wt%, 0.5 wt%, 0.8 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, or any parameter range between two values, preferably 0.1–1 wt%; more preferably 0.1–0.82 wt%.

[0014] Based on the catalyst by weight of 100%,

[0015] The content of the active component is 0.05-60 wt%, for example, it can be 0.05 wt%, 0.1 wt%, 0.3 wt%, 0.5 wt%, 0.8 wt%, 1 wt%, 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, or any parameter range between two values, preferably 20-50 wt%.

[0016] Preferably,

[0017] The alumina microspheres are monodisperse alumina microspheres, preferably alumina microspheres with an average diameter of 200-800 μm and a coefficient of variation of 3-8%.

[0018] In this invention, alumina microspheres can be prepared in-house or purchased from existing alumina microspheres that meet the requirements.

[0019] Preferably,

[0020] The active component is selected from at least one of Ni, Cu, Co, Pd, Pt, Ru, Rh, or Fe;

[0021] In this invention, the metal corresponding to the active component is in a reduced or oxidized state. In use, the oxidized catalyst can be reduced using conventional reduction methods.

[0022] A second objective of this invention is to provide a method for preparing the catalyst supported on carbon-modified alumina microspheres as described in one objective of this invention, the preparation method comprising the following steps:

[0023] (1) Alumina microspheres were added to a nitrogen-containing polymer solution, and then reacted by a solvothermal method. After post-treatment, a nitrogen-containing polymer-modified alumina microsphere composite carrier was obtained.

[0024] (2) The alumina microsphere composite carrier modified with nitrogen-containing polymer was calcined under an inert atmosphere to obtain a carbon-modified alumina microsphere composite carrier.

[0025] (3) The carbon-modified alumina microsphere composite support is immersed in the active component precursor solution, taken out, dried, and calcined to obtain the catalyst supported on carbon-modified alumina microspheres.

[0026] Preferably,

[0027] In step (1),

[0028] The nitrogen-containing polymer is selected from one or a combination of polyvinylimidazolium, polyvinylpyrrolidone, or polyvinylpyridine; and / or,

[0029] The concentration of the nitrogen-containing polymer solution is 0.1–2 wt%; preferably 0.6–1.8 wt%; and / or,

[0030] In the nitrogen-containing polymer solution, the solvent is selected from one or a combination of methanol and ethanol.

[0031] Preferably,

[0032] In step (1),

[0033] The mass ratio of the alumina microspheres to the nitrogen-containing polymer solution is 1:1 to 10; and / or,

[0034] The reaction temperature of the solvothermal method is 100–120°C, and the reaction time is 4–10 h.

[0035] The alumina microspheres were prepared using a microchannel reactor.

[0036] The microchannel reactor can be any commonly used microchannel reactor in the prior art, and can be a single-channel reactor or a multi-channel reactor.

[0037] The multi-channel reactor can preferably be an eight-channel reactor. In this invention, the structure of the eight-channel reactor is preferably that of the eight-channel reactor disclosed in Chinese Patent CN113041974A, which is used for the large-scale preparation of alumina microspheres.

[0038] Alumina microspheres are obtained by using aluminum sol as the dispersed phase and organic solvent as the continuous phase through a microchannel reactor, followed by solidification, drying and calcination.

[0039] More

[0040] The solid content of aluminum sol is 5-10 wt%.

[0041] The continuous phase flow rate is 6-10 mL / min, preferably 7-9 mL / min;

[0042] The dispersed phase flow rate is 1-4 mL / min, preferably 2-3 mL / min;

[0043] The roasting temperature is 500-800℃, and the time is 3-6 hours.

[0044] In this invention, the organic solvent can be any conventional organic solvent used in microchannel reactors, with octanol being preferred.

[0045] Preferably,

[0046] In step (2) of the present invention,

[0047] The roasting temperature and time should be sufficient to achieve carbonization; preferably, the roasting temperature is 400–800℃; more preferably, it is 600–800℃; and / or,

[0048] The preferred roasting time is 2 to 10 hours, and more preferably 2 to 3 hours.

[0049] Preferably,

[0050] In step (3),

[0051] The precursor solution of the active component is selected from the active component salt solution, preferably a nitrate solution; more preferably from at least one of nickel nitrate solution, copper nitrate solution, cobalt nitrate solution, palladium nitrate solution, ruthenium nitrate solution, platinum nitrate solution, or ferric nitrate solution; and / or,

[0052] The concentration of metal ions in the precursor solution of the active component is 0.1–25 wt%; more preferably 10–15 wt%; and / or,

[0053] The mass ratio of the carbon-modified alumina microsphere composite carrier to the active component precursor solution is 1:1 to 10; and / or,

[0054] The carbon-modified alumina microsphere composite carrier is immersed in the active component precursor solution for 1–5 hours; and / or,

[0055] The roasting temperature is 300–600℃; the roasting time is 4–8 hours.

[0056] In this invention, the post-processing of step (1) can be performed using existing conventional processing methods, such as cooling and filtration.

[0057] The inert atmosphere in step (2) can be any conventional inert atmosphere, preferably a nitrogen atmosphere;

[0058] The drying in step (3) can be carried out under existing conventional drying conditions, preferably at 100-140℃ for 10-15 hours.

[0059] A third objective of this invention is to provide the application of the catalyst supported on carbon-modified alumina microspheres as described in one objective of this invention in the hydrogenation reaction of n-butyraldehyde.

[0060] In this invention, the hydrogenation reaction of n-butyraldehyde can be carried out under existing conventional hydrogenation reaction conditions.

[0061] Compared with the prior art, the present invention has at least the following advantages:

[0062] (1) In the catalyst of the present invention, carbon is uniformly covered on the surface of the alumina microsphere carrier with abundant mesoporous structure, so that the surface of the alumina microsphere carrier is covered by carbon elements as much as possible, forming a carbon-modified alumina microsphere composite carrier.

[0063] (2) In the catalyst of the present invention, the acidity of the surface of the carbon-modified alumina microspheres is significantly reduced, which helps to avoid byproducts generated by acid catalysis, thereby improving the reaction selectivity.

[0064] (3) The catalyst of the present invention has a narrow particle size distribution. Macroscopically, each catalyst particle can be considered to have the same size, which is conducive to the uniform distribution of materials in the reactor, can avoid hot spots in the reactor, thereby avoiding reaction runaway and improving reaction selectivity.

[0065] (4) The catalyst of the present invention has a higher surface area, higher utilization rate of active components, and higher catalytic activity.

[0066] (5) The catalyst of the present invention can be applied to dynamic reactors such as moving beds and fluidized beds, which can minimize catalyst wear and improve reaction efficiency. Attached Figure Description

[0067] Figure 1 Microscopic images of the carbon-modified alumina microsphere composite carrier of the present invention;

[0068] Figure 2 This is a particle size distribution diagram of the carbon-modified alumina microsphere composite carrier of the present invention. Detailed Implementation

[0069] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0070] The average diameter of the alumina microspheres was calculated by measuring the diameter of each alumina microsphere based on microscope images.

[0071] The coefficient of variation of alumina microspheres is calculated according to the following formula:

[0072]

[0073] CV: Coefficient of variation, n: Alumina particle count, X: Alumina particle size.

[0074] Example 1

[0075] Step 1: Preparation of monodisperse alumina microspheres using an eight-channel microreactor

[0076] The dispersed phase was an aluminum sol (aluminum sol obtained by reacting aluminum hydroxide and excess sodium hydroxide) with a solid content of 7.5 wt%. The continuous phase and the liquid in the oil column were both organic solvents, specifically octanol. First, the flow rate of the continuous phase was adjusted to fill the continuous phase distribution layer and flow into the droplet formation layer, then flow out from the outlet. The continuous phase flow rate was eventually stabilized at 7 mL / min. Then, the dispersed phase flow rate was adjusted to 2 mL / min to fill the dispersed phase distribution layer and flow into the droplet formation layer, further generating droplets under the shearing action of the continuous phase. The droplets solidified in the oil column to obtain gel microspheres. After drying at 120℃ for 12 hours and calcining at 600℃ for 4 hours, alumina microspheres with an average diameter of 345 μm and a coefficient of variation of 6.5% were obtained.

[0077] Step 2: Preparation of carbon-modified alumina microspheres

[0078] Take 20g of the above alumina microspheres and immerse them in an ethanol solution of polyvinylimidazole with a concentration of 1.8wt%, with a mass ratio of alumina microspheres to polyvinylimidazole ethanol solution of 1:10; then transfer them to a hydrothermal reactor and react at 100℃ for 10h, cool and filter to obtain polymer-modified alumina microsphere composite carrier.

[0079] The polymer-modified alumina microsphere composite carrier obtained above was placed in a nitrogen atmosphere and calcined at 600°C for 5 hours to obtain a carbon-modified alumina microsphere composite carrier. The corresponding electron microscopy images and particle size distribution diagrams are shown below. Figure 1 , 2 As shown.

[0080] Step 3: Preparation of nickel catalyst supported on carbon-modified alumina microspheres

[0081] Take 200g of a nickel nitrate aqueous solution containing 15wt% Ni and put it into a beaker. Place 20g of carbon-modified alumina microspheres into the Ni aqueous solution. After 1 hour, take out the alumina microspheres, drain them, dry them at 120℃ for 12 hours, and calcine them at 400℃ for 6 hours under nitrogen protection to obtain the nickel catalyst supported on alumina microspheres.

[0082] The component contents of the catalysts prepared by the above method are shown in Table 1.

[0083] Example 2

[0084] Step 1: Preparation of monodisperse alumina microspheres using an eight-channel microreactor

[0085] The dispersed phase was an aluminum sol (aluminum sol obtained by reacting aluminum hydroxide and excess sodium hydroxide) with a solid content of 7.5 wt%. The continuous phase and the liquid in the oil column were both organic solvents, specifically octanol. First, the flow rate of the continuous phase was adjusted to fill the continuous phase distribution layer and flow into the droplet generation layer, then flow out from the outlet. The continuous phase flow rate was eventually stabilized at 9 mL / min. Then, the flow rate of the dispersed phase was adjusted to 3 mL / min to fill the dispersed phase distribution layer and flow into the droplet generation layer, further generating droplets under the shearing action of the continuous phase. The droplets solidified in the oil column to obtain gel microspheres. After drying at 120℃ for 12 hours and calcining at 600℃ for 4 hours, alumina microspheres with an average diameter of 480 μm and a coefficient of variation of 7.2% were obtained.

[0086] Step 2: Preparation of carbon-modified alumina microspheres

[0087] Take 20g of the above alumina microspheres and immerse them in an ethanol solution of 0.6wt% polyvinylimidazole, with a mass ratio of alumina microspheres to polyvinylimidazole ethanol solution of 1:2; then transfer them to a hydrothermal reactor and react at 100℃ for 10h, cool and filter to obtain polymer-modified alumina microsphere composite carrier.

[0088] The polymer-modified alumina microsphere composite carrier obtained above was placed in a nitrogen atmosphere and calcined at 800°C for 3 hours to obtain a carbon-modified alumina microsphere composite carrier.

[0089] Step 3: Preparation of nickel catalyst supported on carbon-modified alumina microspheres

[0090] Take 200g of a nickel nitrate aqueous solution containing 10wt% Ni and place it in a beaker. Place 20g of carbon-modified alumina microspheres in the Ni aqueous solution. After 1 hour, remove the alumina microspheres, drain them, dry them at 120℃ for 12 hours, and calcine them at 400℃ for 6 hours under nitrogen protection to obtain the nickel catalyst supported on alumina microspheres.

[0091] The component contents of the catalysts prepared by the above method are shown in Table 1.

[0092] Comparative Example 1

[0093] Step 1: Preparation of monodisperse alumina microspheres using an eight-channel microreactor

[0094] The dispersed phase was an aluminum sol (aluminum sol obtained by reacting aluminum hydroxide and excess sodium hydroxide) with a solid content of 7.5 wt%. The continuous phase and the liquid in the oil column were both organic solvents, specifically octanol. First, the flow rate of the continuous phase was adjusted to fill the continuous phase distribution layer and flow into the droplet formation layer, then flow out from the outlet. The continuous phase flow rate was eventually stabilized at 7 mL / min. Then, the dispersed phase flow rate was adjusted to 2 mL / min to fill the dispersed phase distribution layer and flow into the droplet formation layer, further generating droplets under the shearing action of the continuous phase. The droplets solidified in the oil column to obtain gel microspheres. After drying at 120℃ for 12 hours and calcining at 600℃ for 4 hours, alumina microspheres with an average diameter of 345 μm and a coefficient of variation of 6.5% were obtained.

[0095] Step 2: Preparation of nickel catalyst supported on alumina microspheres

[0096] Take 200g of a 15wt% Ni-nitric acid aqueous solution and place it in a beaker. Place 20g of carbon-modified alumina microspheres in the Ni aqueous solution. After 1 hour, remove the alumina microspheres, drain them, dry them at 120℃ for 12 hours, and calcine them at 400℃ for 6 hours under nitrogen protection to obtain the nickel catalyst supported on alumina microspheres.

[0097] The component contents of the catalysts prepared by the above method are shown in Table 1.

[0098] Table 1. Component content of the catalyst

[0099]

[0100] Example 3

[0101] The application effect of the catalyst prepared in Example 1 above in the hydrogenation reaction of n-butyraldehyde was investigated.

[0102] Hydrogenation of n-butyraldehyde: n-Butanol is obtained by liquid-phase hydrogenation of n-butyraldehyde. After hydrogenation using traditional catalysts, the content of n-butyl ether in the product is relatively high. When it accumulates to a certain extent, it not only increases the energy consumption for separation, but also affects the quality of the final product due to the difficulty in separation. Therefore, a catalyst with better selectivity is needed.

[0103] The reaction performance of the catalyst was evaluated using fixed-bed n-butyraldehyde liquid-phase hydrogenation. 50 ml of catalyst was loaded into a fixed-bed reactor. The hydrogen flow rate was 100 ml / min, the reaction temperature was 90–120 °C, the pressure was 3.0 MPa, and the n-butyraldehyde volume hourly space velocity was 0.2 h⁻¹. -1 The reaction products were quantified using gas chromatography with an FID detector. The experimental results are shown in Table 2.

[0104] Example 4

[0105] The application effect of the catalyst prepared in Example 2 above in the hydrogenation reaction of n-butyraldehyde was investigated.

[0106] Hydrogenation of n-butyraldehyde: n-Butanol is obtained by liquid-phase hydrogenation of n-butyraldehyde. After hydrogenation using traditional catalysts, the content of n-butyl ether in the product is relatively high. When it accumulates to a certain extent, it not only increases the energy consumption for separation, but also affects the quality of the final product due to the difficulty in separation. Therefore, a catalyst with better selectivity is needed.

[0107] The reaction performance of the catalyst was evaluated using fixed-bed n-butyraldehyde liquid-phase hydrogenation. 50 ml of catalyst was loaded into a fixed-bed reactor. The hydrogen flow rate was 100 ml / min, the reaction temperature was 90–120 °C, the pressure was 3.0 MPa, and the n-butyraldehyde volume hourly space velocity was 0.2 h⁻¹. -1 The reaction products were quantified using gas chromatography with an FID detector. The experimental results are shown in Table 2.

[0108] Example 5

[0109] The application effect of the catalyst prepared in Comparative Example 1 above in the hydrogenation reaction of n-butyraldehyde was investigated.

[0110] Hydrogenation of n-butyraldehyde: n-Butanol is obtained by liquid-phase hydrogenation of n-butyraldehyde. After hydrogenation using traditional catalysts, the content of n-butyl ether in the product is relatively high. When it accumulates to a certain extent, it not only increases the energy consumption for separation, but also affects the quality of the final product due to the difficulty in separation. Therefore, a catalyst with better selectivity is needed.

[0111] The reaction performance of the catalyst was evaluated using fixed-bed n-butyraldehyde liquid-phase hydrogenation. 50 ml of catalyst was loaded into a fixed-bed reactor. The hydrogen flow rate was 100 ml / min, the reaction temperature was 90–120 °C, the pressure was 3.0 MPa, and the n-butyraldehyde volume hourly space velocity was 0.2 h⁻¹. -1 The reaction products were quantified using gas chromatography with an FID detector. The experimental results are shown in Table 2.

[0112] Table 2. Content of n-butyl ether in the product after hydrogenation reaction at different temperatures.

[0113]

[0114] As can be seen from the data in Table 2, the content of n-butyl ether in the n-butanol product of the catalysts prepared in Examples 1-2 of the present invention is significantly lower than that in Comparative Example 1, indicating that the catalysts prepared in the examples of the present invention have better reaction selectivity.

[0115] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

[0116] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

Claims

1. The application of a catalyst supported on carbon-modified alumina microspheres in the hydrogenation reaction of n-butyraldehyde, characterized in that, The catalyst comprises a carbon-modified alumina microsphere composite support and an active component supported on the composite support; Based on the weight of the composite carrier as 100%, The carbon content is 0.1~1wt%; Based on the catalyst by weight of 100%, The content of the active ingredient is 0.05~60 wt%; The preparation method of carbon-modified alumina microsphere composite carrier includes the following steps: (1) Alumina microspheres were added to a nitrogen-containing polymer solution, and then reacted by a solvothermal method. After post-treatment, a nitrogen-containing polymer-modified alumina microsphere composite carrier was obtained. (2) The alumina microsphere composite carrier modified with nitrogen-containing polymer was calcined under an inert atmosphere to obtain a carbon-modified alumina microsphere composite carrier. The nitrogen-containing polymer is selected from one or a combination of polyvinylimidazolium, polyvinylpyrrolidone, or polyvinylpyridine. The catalyst supported on the carbon-modified alumina microspheres is a catalyst used for the hydrogenation reaction of n-butyraldehyde.

2. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 1 in the hydrogenation reaction of n-butyraldehyde, characterized in that, The catalyst is calculated by weight of 100%. The content of the active component is 20~50wt%.

3. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 1 in the hydrogenation reaction of n-butyraldehyde, characterized in that, The alumina microspheres are monodisperse alumina microspheres.

4. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 3 in the hydrogenation reaction of n-butyraldehyde, characterized in that, The alumina microspheres are selected from alumina microspheres with an average diameter of 200-800 μm and a coefficient of variation of 3-8%.

5. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 1 in the hydrogenation reaction of n-butyraldehyde, characterized in that, The active component is selected from at least one of Ni, Cu, Co, Pd, Pt, Ru, Rh or Fe.

6. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 1 in the hydrogenation reaction of n-butyraldehyde, characterized in that, The preparation method of the catalyst supported on carbon-modified alumina microspheres includes the following steps: (1) Alumina microspheres were added to a nitrogen-containing polymer solution, and then reacted by a solvothermal method. After post-treatment, a nitrogen-containing polymer-modified alumina microsphere composite carrier was obtained. (2) The alumina microsphere composite carrier modified with nitrogen-containing polymer was calcined under an inert atmosphere to obtain a carbon-modified alumina microsphere composite carrier. (3) The carbon-modified alumina microsphere composite support is immersed in the active component precursor solution, taken out, dried, and calcined to obtain the catalyst supported on carbon-modified alumina microspheres.

7. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 6 in the hydrogenation reaction of n-butyraldehyde, characterized in that, In step (1), The concentration of the nitrogen-containing polymer solution is 0.1~2 wt%; and / or, In the nitrogen-containing polymer solution, the solvent is selected from one or a combination of methanol and ethanol.

8. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 7 in the hydrogenation reaction of n-butyraldehyde, characterized in that, In step (1), The concentration of the nitrogen-containing polymer solution is 0.6~1.8 wt%.

9. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 6 in the hydrogenation reaction of n-butyraldehyde, characterized in that, In step (1), The mass ratio of the alumina microspheres to the nitrogen-containing polymer solution is 1:1~10; and / or, The reaction temperature of the solvothermal method is 100~120℃, and the reaction time is 4~10h.

10. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 6 in the hydrogenation reaction of n-butyraldehyde, characterized in that, In step (1), The alumina microspheres were prepared using a microchannel reactor.

11. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 10 in the hydrogenation reaction of n-butyraldehyde, characterized in that, Using aluminum sol as the dispersed phase and an organic solvent as the continuous phase, a dispersed phase droplets were obtained through a microchannel reactor, and then solidified, dried and calcined sequentially to obtain alumina microspheres.

12. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 11 in the hydrogenation reaction of n-butyraldehyde, characterized in that, The solid content of aluminum sol is 5-10 wt%; The continuous phase flow rate is 6-10 mL / min, and the dispersed phase flow rate is 1-4 mL / min; The roasting temperature is 500-800℃, and the time is 3-6 hours.

13. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 6 in the hydrogenation reaction of n-butyraldehyde, characterized in that, In step (2), The roasting temperature is 400~800℃; the roasting time is 2~10h.

14. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 6 in the hydrogenation reaction of n-butyraldehyde, characterized in that, In step (3), The active component precursor solution is selected from the active component salt solution; and / or, The concentration of metal ions in the precursor solution of the active component is 0.1~25wt%; and / or, The mass ratio of carbon-modified alumina microsphere composite carrier to the active component precursor solution is 1:1~10; and / or, The carbon-modified alumina microsphere composite carrier is immersed in the active component precursor solution for 1–5 h; and / or, The roasting temperature is 300~600℃; the roasting time is 4~8h.

15. The application of the catalyst supported on carbon-modified alumina microspheres according to claim 14 in the hydrogenation reaction of n-butyraldehyde, characterized in that, In step (3), The active component precursor solution is selected from nitrate solutions; and / or, The concentration of metal ions in the active component precursor solution is 10~15 wt%.

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