CN115722241A

CN115722241A - Preparation method of selective oxidation catalyst and application of selective oxidation catalyst in synthesis of 2, 5-diformylfuran

Info

Publication number: CN115722241A
Application number: CN202110991167.9A
Authority: CN
Inventors: 郑路凡; 赵红; 孙乾辉; 陈公哲; 杜泽学; 荣峻峰; 宗保宁
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2021-08-26
Filing date: 2021-08-26
Publication date: 2023-03-03

Abstract

The invention relates to a preparation method of a selective oxidation catalyst and application of the selective oxidation catalyst in synthesizing 2, 5-diformylfuran, wherein the preparation method of the selective oxidation catalyst comprises the following steps: s1, impregnating a carbon-containing material by using a water solution containing a nitrogen element, drying, and performing first roasting in an inert gas to obtain a nitrogen-doped carbon carrier; s2, mixing the nitrogen-doped carbon carrier with an active metal component compound solution to obtain a first mixture; s3, carrying out primary drying and primary reduction on the first mixture. The selective oxidation catalyst can catalyze to obtain 2, 5-diformylfuran with high selectivity, and slow down the process of the product continuing to generate oxidation reaction.

Description

Preparation method of selective oxidation catalyst and application of selective oxidation catalyst in synthesis of 2, 5-diformylfuran

Technical Field

The application relates to the field of chemistry and chemical engineering, in particular to a preparation method of a catalyst and a method for synthesizing 2, 5-diformylfuran by selective oxidation of 5-hydroxymethylfurfural.

Background

With the consumption of fossil fuels and the impact on the environment, there is a worldwide wide focus on finding sustainable alternative energy sources and chemicals. The biomass resource has wide sources, low price and rich reserves, more importantly, the specific gravity of carbohydrate is large, and the important biomass-based platform compound 5-Hydroxymethylfurfural (HMF) can be prepared by catalyzing the dehydration of the carbohydrate such as fructose, glucose, cellulose and the like through acid. HMF has methylol and aldehyde functional groups, has active chemical properties, and can be synthesized into a series of platform compounds such as 2, 5-furandicarboxylic acid (FDCA) and 2, 5-Diformylfuran (DFF) through selective oxidation or hydrogenation reduction, wherein the DFF can be used for preparing pesticide intermediates, bactericides and heterocyclic compounds. The efficient oxidation of HMF to prepare DFF is realized, which is beneficial to opening up the biomass utilization path from cellulose to HMF and then to chemical raw materials, and lays an important foundation for replacing fossil resources in the future.

At present, DFF is prepared by selectively oxidizing HMF mainly by using stoichiometric chemical oxidants such as manganese dioxide, chromium trioxide and sodium hypochlorite, but the DFF has the disadvantages of serious environmental pollution, long reaction time, large consumption of oxidants and reaction solvents, low product yield and unsuitability for large-scale industrial production. In recent years, some researchers use oxygen or air as an oxidant, for example, in CN109174153A in the prior art, 5-hydroxymethylfurfural is used as a raw material, oxygen or air is used as an oxidant, a C-N material doped with nitrogen and a carbon material is used as a catalyst, and acetic acid is used as a solvent, so that a target product of 98% can be obtained at most, but 65-68% of concentrated nitric acid needs to be added in the reaction, so that the problems of safety, corrosion and the like exist, and in addition, the concentration of a reactant is less than 1%, so that the problem of treatment of a large amount of waste water and waste reagents is involved, and the industrial amplification application is not facilitated.

Therefore, there is a need in the art for further catalyst activity and cycle stability, increasing 5-hydroxymethylfurfural conversion and selectivity to 2, 5-diformylfuran.

Disclosure of Invention

The purpose of the disclosure is to provide a high-efficiency stable supported metal catalyst, and develop a mild-condition green and environment-friendly reaction system, so that 5-hydroxymethylfurfural is oxidized to prepare 2, 5-diformylfuran with high selectivity.

In order to achieve the above object, the present disclosure provides, in a first aspect, a method for preparing a selective oxidation catalyst, the method comprising:

s1, impregnating a carbon-containing material by using a water solution containing a nitrogen element, drying, and performing first roasting in an inert gas to obtain a nitrogen-doped carbon carrier;

s2, mixing the nitrogen-doped carbon carrier with an active metal component compound solution to obtain a first mixture;

s3, carrying out primary drying and primary reduction on the first mixture.

Optionally, the carbonaceous material has a specific surface area of 200 to 2500m ² A ratio of/g, preferably 800 to 1800m ² (ii)/g; the carbon-containing material is selected from at least one of activated carbon, carbon black, carbon nanotubes, graphene and graphene oxide, and is preferably activated carbon and/or carbon black; the aqueous solution containing nitrogen element is selected from ammonia solution and/or urea solution; the mass ratio of the carbon-containing material to the nitrogen element is 30:1-1:2, preferably 25:1-1:1.

alternatively, the active metal component compound is selected from soluble metal compounds of group VIII metals; optionally, the soluble metal compound of the group VIII metal is at least one of a nitrate, an acetate, a soluble carbonate, a chloride, and a soluble complex of the group VIII metal; the group VIII metal is at least one selected from rhodium element, palladium element and ruthenium element; preferably, the active metal component compound is a chloride of a group VIII metal; further preferably, the active metal component compound is ruthenium chloride.

Optionally, the mass fraction of the active metal component elements is 1% to 25%, preferably 5% to 15%, based on the mass of the catalyst.

Optionally, in step S1, the impregnation conditions include: the dipping temperature is 15-40 ℃, and the preferred temperature is 20-30 ℃; the dipping time is 12 to 36 hours, preferably 18 to 24 hours; the conditions of the first firing include: the roasting temperature is 1000-1500 ℃, and the preferential temperature is 1100-1300 ℃; the roasting time is 2 to 12 hours, preferably 4 to 8 hours;

in step S2, the mixing is equal-volume impregnation mixing; the mixing conditions include: the mixing temperature is 15-40 ℃, preferably 20-30 ℃; the mixing time is 12 to 36 hours, preferably 18 to 28 hours;

in step S3, the conditions of the first drying include: the drying temperature is 60-140 ℃, preferably 90-120 ℃; the drying time is 6-24 hours, preferably 10-18 hours; the conditions of the first reduction include: under a reducing atmosphere containing hydrogen; preferably, the reducing atmosphere contains 10 to 100 volume% of hydrogen and 0 to 90 volume% of inert gas; the reduction temperature is 200-800 ℃, preferably 350-650 ℃; the reduction time is 2 to 6 hours, preferably 2.5 to 4.5 hours.

A second aspect of the present disclosure provides a selective oxidation catalyst comprising a nitrogen-doped carbon support and an active metal component; the nitrogen-doped carbon carrier has a specific surface area of 200-2500m ² (iv) g; in the nitrogen-doped carbon carrier, the mass fraction of nitrogen is 0.01-5 wt%, and the mass fraction of oxygen is 3-15 wt%; the active metal component is present in an amount of from 1 to 25 wt% based on the weight of the selective oxidation catalyst.

Optionally, XPS analyzed N of the nitrogen-doped carbon support _1s In the spectrum peak, a characteristic peak is present between 399 and 400.5 eV.

Alternatively, the active metal component compound is selected from oxides of group VIII metals; preferably, the oxide of the group VIII metal is an oxide of at least one of rhodium, palladium and ruthenium; further preferably, the oxide of the group VIII metal is an oxide of ruthenium.

A third aspect of the present disclosure provides a method for preparing 2, 5-diformylfuran, comprising:

SS1, dissolving 5-hydroxymethylfurfural in an organic solvent to obtain a mixed solution;

SS2, adding a selective oxidation catalyst into the mixed solution to carry out oxidation reaction;

wherein, the selective oxidation catalyst is the selective oxidation catalyst prepared by the preparation method or the selective oxidation catalyst.

Optionally, the mass ratio of the organic solvent to 5-hydroxymethylfurfural is 2-50:1, preferably 5 to 20:1; the molar ratio of the 5-hydroxymethylfurfural to the active metal component in the selective oxidation catalyst is 80-450:1, preferably from 100 to 320:1; optionally, the organic solvent is selected from one or more of toluene, dioxane, N-dimethylformamide, N-dimethylacetamide, N-dimethylsulfoxide, tetrahydrofuran, pyridine, and acetonitrile.

Alternatively, in step SS2, the oxidation reaction conditions include: the oxygen partial pressure is 0.05MPa-2MPa, preferably 0.5MPa-1MPa; the reaction temperature is 50-200 ℃, preferably 80-120 ℃; the reaction time is 0.5h-10h, preferably 1h-4h.

Through above-mentioned technical scheme, this disclosure has following beneficial effect:

(1) According to the method, the carbon-containing material is subjected to nitrogen doping treatment, so that on one hand, a noble metal catalyst with high loading capacity can be obtained, the utilization rate of active metal can be kept, the activity of the catalyst is improved, and meanwhile, the using amount of the catalyst can be properly reduced, so that the cost is saved; on the other hand, the modification of the carrier is beneficial to the desorption of the product on the surface of the catalyst, and the product is prevented from being further oxidized to generate other byproducts. Therefore, the catalyst can promote the catalytic conversion of high-concentration reactants to obtain high-selectivity target products.

(2) The reaction solvent used in the method adopts a conventional organic solvent, is cheap and easy to obtain, adopts air or oxygen as an oxygen source, avoids using organic oxidants such as nitrate and the like, simplifies the post-treatment steps of the product, avoids the problems of acid-containing wastewater discharge and the like, reduces energy consumption, is green and environment-friendly, and has wide industrial application prospect.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

FIG. 1 is an XPS spectrum of a nitrogen doped carbon support of example 1;

FIG. 2 is an XPS spectrum of the nitrogen doped carbon support of example 2;

fig. 3 is an XPS spectrum of the nitrogen-doped carbon support of example 3.

Detailed Description

The following describes in detail specific embodiments of the present disclosure. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

The present disclosure provides, in a first aspect, a method of preparing a selective oxidation catalyst, the method comprising;

s3, carrying out first drying and first reduction on the first mixture.

The invention provides a nitrogen-doped modification method of a carbon-containing material, which adopts a nitrogen-doped carbon material as a carrier and loads a catalyst prepared from a noble active metal component, can catalyze and obtain 2, 5-diformylfuran with high selectivity, and slows down the process of the product which continuously generates an oxidation reaction.

According to the first aspect of the present disclosure, the carbonaceous material may have a specific surface area of 200 to 2500m ² A ratio of 800 to 1800 m/g is preferred ² (iv) g; the carbonaceous material may be selected from at least one of activated carbon, carbon black, carbon nanotubes, graphene and graphene oxide, preferably activated carbon and/or carbon black; the water solution containing nitrogen element can be selected from ammonia water solution and/or urea solution; the mass ratio of the carbonaceous material to the nitrogen element may be 30:1-1:2, preferably 25:1-1:1.

according to a first aspect of the disclosure, XPS analysis of the nitrogen-doped carbon support for N _1s The spectral peak has a characteristic peak between 399eV and 400.5 eV.

According to a first aspect of the present disclosure, the active metal component compound may be selected from soluble metal compounds of group VIII metals; optionally, the soluble metal compound of the group VIII metal is at least one of a nitrate, an acetate, a soluble carbonate, a chloride, and a soluble complex of the group VIII metal; the group VIII metal may be at least one selected from rhodium, palladium and ruthenium; preferably, the active metal component compound is a chloride of a group VIII metal; further preferably, the active metal component compound is ruthenium chloride.

According to the first aspect of the present disclosure, the mass fraction of the active metal component element may be 1% to 25%, preferably 5% to 15%, based on the mass of the catalyst.

According to the first aspect of the present disclosure, in step S1, the conditions of the impregnation may include: the dipping temperature is 15-40 ℃, and the preferred temperature is 20-30 ℃; the dipping time is 12 to 36 hours, preferably 18 to 24 hours; the conditions of the first firing may include: the roasting temperature is 1000-1500 ℃, and the preferential temperature is 1100-1300 ℃; the roasting time is 2 to 12 hours, preferably 4 to 8 hours;

in step S2, the mixing may be isochoric dip mixing; the conditions for the mixing may include: the mixing temperature is 15-40 ℃, preferably 20-30 ℃; the mixing time is 12 to 36 hours, preferably 18 to 28 hours;

in step S3, the conditions of the first drying may include: the drying temperature is 1000-1500 ℃, preferably 90-120 ℃; the drying time is 0.2 to 12 hours, preferably 10 to 18 hours; the conditions of the first reduction may include: under a reducing atmosphere containing hydrogen; preferably, the reducing atmosphere contains 10 to 100 volume% of hydrogen and 0 to 90 volume% of inert gas; the reduction temperature is 200-800 ℃, preferably 350-650 ℃; the reduction time is 2 to 6 hours, preferably 2.5 to 4.5 hours.

A second aspect of the present disclosure provides a selective oxidation catalyst comprising a nitrogen-doped carbon support and an active metal component; the specific surface area of the nitrogen-doped carbon carrier is 200-2500m ² (iv) g; in the nitrogen-doped carbon carrier, the mass fraction of nitrogen is 0.01-5 wt%, and the mass fraction of oxygen is 3-15 wt%; the active metal component is present in an amount of from 1 to 25 wt% based on the weight of the selective oxidation catalyst.

According to a second aspect of the disclosure, XPS analyzed N of the nitrogen-doped carbon support _1s In the spectrum peak, a characteristic peak is present between 399 and 400.5 eV.

According to a second aspect of the present disclosure, the active metal component compound may be selected from oxides of group VIII metals; preferably, the oxide of the group VIII metal is an oxide of at least one of rhodium, palladium and ruthenium; further preferably, the oxide of the group VIII metal is an oxide of ruthenium.

SS2, adding a selective oxidation catalyst into the mixed solution to perform an oxidation reaction;

The preparation method of the 2, 5-diformylfuran can improve the single-pass treatment capacity of the 5-hydroxymethylfurfural and ensure that a target product with high selectivity is obtained under the condition of high-concentration reactants.

According to a third aspect of the present disclosure, the mass ratio of the organic solvent to 5-hydroxymethylfurfural may be 2 to 50:1, preferably 5 to 20:1; the molar ratio of the 5-hydroxymethylfurfural to the active metal component in the selective oxidation catalyst is 80-450:1, preferably 100 to 320:1; optionally, the organic solvent is selected from one or more of toluene, dioxane, N-dimethylformamide, N-dimethylacetamide, N-dimethylsulfoxide, tetrahydrofuran, pyridine, and acetonitrile.

According to the third aspect of the present disclosure, in step SS2, the oxidation reaction may be performed under an oxygen atmosphere or an air atmosphere, and the conditions of the oxidation reaction may include: the oxygen partial pressure is 0.05MPa-2MPa, preferably 0.5MPa-1MPa; the reaction temperature is 50-200 ℃, and preferably 80-120 ℃; the reaction time is 0.5h-10h, preferably 1h-4h.

The present disclosure is further illustrated by the following examples. The raw materials used in the examples are all available from commercial sources. Wherein the activated carbon is coconut shell carbon, and the source of the manufacturer comprises Beijing university Macro science and technology company, inc. and Kaldo carbon (Suzhou) company, inc. (No. 107C); the carbon Black comprises EC-300J, EC-600JD, ECP-600JD, VXC72 and Black pearls 2000.

Example 1

This example illustrates the preparation of nitrogen-doped carbon materials according to the present disclosure.

1g of Carrageenan activated carbon 107C is immersed in 15mL of a 0.7wt% aqueous urea solution for 24 hours; drying in an oven at 100 ℃; then placing the tube furnace into a tube furnace, heating the tube furnace to 1200 ℃ at a speed of 10 ℃/min in an argon atmosphere, and carrying out constant temperature treatment for 3h; and naturally cooling to obtain the nitrogen-doped carbon carrier, which is numbered as carbon carrier A.

The nitrogen mass fraction by XPS analysis was 0.68%; the oxygen mass fraction by XPS analysis was 8.92%; specific surface area is 1230m ² (ii) in terms of/g. FIG. 1 is a schematic representation of the nitrogen-doped carbon support of example 1XPS spectra.

Example 2

Adding 10mL of absolute ethanol into 1g of Ketjenblack ECP600JD, and then adding 25mL of 10wt% ammonia water solution for soaking for 24h; drying in an oven at 100 ℃; then placing the tube furnace into a tube furnace, heating the tube furnace to 1100 ℃ at the speed of 8 ℃/min in the argon atmosphere, and carrying out constant temperature treatment for 3h; and naturally cooling to obtain the nitrogen-doped carbon carrier, which is numbered as carbon carrier B.

The nitrogen mass fraction by XPS analysis was 1.48%; the oxygen mass fraction by XPS analysis was 11.22%; specific surface area of 1378m ² (ii) in terms of/g. Fig. 2 is an XPS spectrum of the nitrogen-doped carbon support of example 2.

Example 3

1g Black pearls 2000 was soaked for 24h with 10mL of absolute ethanol and then with 20mL of a 1wt% aqueous solution of urea; drying in an oven at 100 ℃; then placing the tube furnace into a tube furnace, heating the tube furnace to 1300 ℃ at the speed of 10 ℃/min in the argon atmosphere, and carrying out constant temperature treatment for 3h; and naturally cooling to obtain the nitrogen-doped carbon carrier, which is numbered as carbon carrier C.

The nitrogen mass fraction by XPS analysis was 1.31%; the oxygen mass fraction by XPS analysis was 9.54%; the specific surface area is 1385m ² (ii) in terms of/g. Fig. 3 is an XPS spectrum of a nitrogen-doped carbon support of example 3.

Example 4

This example illustrates the preparation of a ruthenium on carbon catalyst of the present disclosure.

RuCl is treated by an equal volume impregnation method ₃ Mixing the aqueous solution with carbon carrier A, stirring and immersing at room temperature for 8h, wherein RuCl ₃ The mass ratio of metal Ru to support a in the aqueous solution was 0.12. The first mixture was then dried at 120 ℃ for 12h to obtain a catalyst precursor. The catalyst precursor was placed in a tube furnace at 20 vol% H ₂ Per 80% by volume N ₂ Reducing for 3h at 600 ℃ in atmosphere to obtain ruthenium-carbon selective oxygen with 11.8wt% of active componentAnd (3) converting the catalyst into a catalyst.

Example 5

This example serves to illustrate the preparation of a ruthenium on carbon selective oxidation catalyst of the present disclosure.

A ruthenium on carbon selective oxidation catalyst was prepared as in example 4, except that: carbon support B prepared in example 2 was used, and RuCl ₃ The mass ratio of the metal Ru to the carrier B in the aqueous solution is 0.2.

Example 6

This example illustrates the preparation of a ruthenium on carbon selective oxidation catalyst of the present disclosure.

A ruthenium on carbon selective oxidation catalyst was prepared as in example 4, except that: carbon support C prepared in example 2 was used, and RuCl ₃ The mass ratio of the metal Ru to the carrier C in the aqueous solution is 0.03.

Example 7

This example illustrates the preparation of a palladium on carbon selective oxidation catalyst of the present disclosure.

A palladium on carbon selective oxidation catalyst was prepared as in example 4, with the only difference that: using PdCl ₂ The carbon carrier A is impregnated by the aqueous solution to obtain the palladium-carbon selective oxidation catalyst with the active component content of 11.8 wt%.

Example 8

This example serves to illustrate the preparation of a rhodium on carbon selective oxidation catalyst of the present disclosure.

A rhodium on carbon selective oxidation catalyst was prepared as in example 4, except that: using RhCl ₃ Impregnating the carbon carrier A with the aqueous solution to obtain the rhodium carbon selective oxidation catalyst with the active component content of 11.8 wt%.

Example 9

This example illustrates the process of the present disclosure for the preparation of 2, 5-diformylfuran.

Adding 1.0g of 5-hydroxymethylfurfural into a 50mL stainless steel high-pressure reaction kettle, adding 10g of solvent toluene to obtain a mixed solution, adding 0.027g of the ruthenium-carbon selective oxidation catalyst obtained in the example 4 into the mixed solution, filling oxygen to 1.2MPa, sealing the reaction kettle, raising the reaction temperature to 110 ℃ by adopting an automatic temperature control program, keeping the temperature for 2 hours under continuous stirring, and keeping the pressure unchanged in the reaction process. After the reaction was completed, it was cooled to room temperature. And filtering and washing the reaction solution to collect the reaction solution. And diluting the reaction solution with deionized water, fixing the volume to 100mL, and sampling for high performance liquid chromatography analysis. The results of the catalytic reaction are shown in Table 1.

Example 10

2, 5-Diformylfuran was prepared according to the procedure in example 9, except that the ruthenium-carbon selective oxidation catalyst of example 5 was selected as the catalyst and the catalyst was added in an amount of 0.016g. The results of the catalytic reaction are shown in Table 1.

Example 11

2, 5-Diformylfuran was prepared according to the procedure in example 9, except that the ruthenium-carbon selective oxidation catalyst of example 6 was selected as the catalyst and the amount of the catalyst added was 0.111g. The results of the catalytic reaction are shown in Table 1.

Example 12

2, 5-Diformylfuran was prepared according to the procedure in example 9 except that the palladium on carbon selective oxidation catalyst of example 7 was selected as the catalyst and the amount of the catalyst added was 0.029g. The catalytic reaction results are shown in table 1.

Example 13

2, 5-Diformylfuran was prepared according to the procedure in example 9 except that the rhodium-carbon selective oxidation catalyst of example 8 was selected as the catalyst and the amount of the catalyst added was 0.028g. The catalytic reaction results are shown in table 1.

Example 14

2, 5-Diformylfuran was prepared according to the method of example 9, except that the mass of the reactant 5-hydroxymethylfurfural was 0.1g and the reaction time was 1h. The results of the catalytic reaction are shown in Table 1.

Comparative example 1

A ruthenium carbon catalyst was prepared according to the method of example 4, except that the support was used with karokang carbon activated carbon 107C which was not subjected to doping treatment. Using the catalyst, 2, 5-diformylfuran was prepared according to the method of example 9, and the results of the catalytic reaction are shown in Table 1.

Comparative example 2

A ruthenium carbon catalyst was prepared according to the method of example 4, except that Black pearls 2000 was used as the support without doping treatment. Using this catalyst, 2, 5-diformylfuran was prepared according to the method of example 9, and the catalytic reaction results are shown in Table 1.

TABLE 1

As can be seen from the results in Table 1, in the reaction for producing 2, 5-diformylfuran, the objective product was 2, 5-diformylfuran, and the byproduct was 5-formyl-2-furancarboxylic acid, which was a product of continued oxidation. Comparing the results of example 9 with those of comparative examples 1 to 2, it can be seen that the noble metal catalyst obtained by subjecting a carbon-containing support to nitrogen doping treatment and then impregnating an active metal component compound solution with the nitrogen-doped carbon support in the synthesis of 2, 5-diformylfuran using 5-hydroxymethylfurfural significantly improves the selectivity for 2, 5-diformylfuran even in the presence of a high concentration of 5-hydroxymethylfurfural.

In addition, the cyclic reaction is carried out according to the method of example 9, the catalyst is recycled for 8 times, the percent conversion of 5-hydroxymethylfurfural is 100%, and the selectivity of 2, 5-diformylfuran can still be about 98%, which shows that the corresponding catalyst has improved stability and recycling performance in the method disclosed by the invention.

The preferred embodiments of the present disclosure have been described in detail above, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

It should be noted that the various features described in the foregoing embodiments may be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the disclosure does not separately describe various possible combinations.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. A method of preparing a selective oxidation catalyst, the method comprising:

s3, carrying out first drying and first reduction on the first mixture.

2. The method of claim 1, wherein the carbonaceous material has a specific surface area of 200-2500m ² A ratio of/g, preferably 800 to 1800m ² (ii)/g; the carbon-containing material is selected from at least one of activated carbon, carbon black, carbon nanotubes, graphene and graphene oxide, and is preferably activated carbon and/or carbon black;

the aqueous solution containing nitrogen element is selected from ammonia solution and/or urea solution;

the mass ratio of the carbon-containing material to the nitrogen element is 30:1-1:2, preferably 25:1-1:1.

3. the method of claim 1, wherein the active metal component compound is selected from soluble metal compounds of group VIII metals;

optionally, the soluble metal compound of the group VIII metal is at least one of a nitrate, an acetate, a soluble carbonate, a chloride, and a soluble complex of the group VIII metal; the VIII group metal is at least one selected from rhodium element, palladium element and ruthenium element;

preferably, the active metal component compound is a chloride of a group VIII metal;

further preferably, the active metal component compound is ruthenium chloride.

4. A process according to claim 1 or 3, wherein the mass fraction of active metal component elements is from 1% to 25%, preferably from 5% to 15%, based on the mass of the catalyst.

5. The method of claim 1, wherein,

in step S1, the impregnation conditions include: the dipping temperature is 15-40 ℃, and the preferable temperature is 20-30 ℃; the dipping time is 12 to 36 hours, preferably 18 to 24 hours;

the conditions of the first firing include: the roasting temperature is 1000-1500 ℃, and the preferential temperature is 1100-1300 ℃; the roasting time is 2 to 12 hours, preferably 4 to 8 hours;

in step S2, the mixing is equal-volume dipping mixing; the mixing conditions include: the mixing temperature is 15-40 ℃, preferably 20-30 ℃; the mixing time is 12 to 36 hours, preferably 18 to 28 hours;

in step S3, the conditions of the first drying include: the drying temperature is 60-140 ℃, preferably 90-120 ℃; the drying time is 6-24 hours, preferably 10-18 hours;

the conditions of the first reduction include: under a reducing atmosphere containing hydrogen; preferably, the reducing atmosphere contains 10 to 100 volume% of hydrogen and 0 to 90 volume% of inert gas; the reduction temperature is 200-800 ℃, preferably 350-650 ℃; the reduction time is 2 to 6 hours, preferably 2.5 to 4.5 hours.

6. A selective oxidation catalyst characterized in that,

the selective oxidation catalyst comprises a nitrogen-doped carbon support and an active metal component;

the nitrogen-doped carbon carrier has a specific surface area of 200-2500m ² (ii)/g; in the nitrogen-doped carbon carrier, the mass fraction of nitrogen is 0.01-5 wt%, and the mass fraction of oxygen is 3-15 wt%;

the active metal component is present in an amount of from 1 to 25 wt.%, based on the weight of the selective oxidation catalyst.

7. The selective oxidation catalyst according to claim 6, wherein the N analyzed by XPS of the nitrogen-doped carbon support _1s Among the spectral peaks, there is a characteristic peak between 399 and 400.5 eV.

8. The selective oxidation catalyst according to claim 6,

the active metal component compound is selected from oxides of group VIII metals;

preferably, the oxide of the group VIII metal is an oxide of at least one of rhodium, palladium and ruthenium;

further preferably, the oxide of the group VIII metal is an oxide of ruthenium.

9. A method for preparing 2, 5-diformylfuran, which comprises the following steps:

wherein the selective oxidation catalyst is a selective oxidation catalyst produced by the method for producing a selective oxidation catalyst according to any one of claims 1 to 5 or the selective oxidation catalyst according to any one of claims 6 to 8.

10. The production method according to claim 9, wherein the mass ratio of the organic solvent to 5-hydroxymethylfurfural is from 2 to 50:1, preferably 5 to 20:1;

the molar ratio of the 5-hydroxymethylfurfural to the active metal component in the selective oxidation catalyst is 80-450:1, preferably from 100 to 320:1;

optionally, the organic solvent is selected from one or more of toluene, dioxane, N-dimethylformamide, N-dimethylacetamide, N-dimethylsulfoxide, tetrahydrofuran, pyridine, and acetonitrile.

11. The process of claim 9, wherein, in step SS2, the oxidation reaction conditions include: the oxygen partial pressure is 0.05MPa-2MPa, preferably 0.5MPa-1MPa; the reaction temperature is 50-200 ℃, and preferably 80-120 ℃; the reaction time is 0.5h-10h, preferably 1h-4h.