A process for the catalytic oxidation of cyclic ketones

Abstract

The present application relates to a kind of catalytic oxidation method of cyclic ketone, which includes: cyclic ketone and oxidant are contacted with catalyst and oxidized, wherein the catalyst contains the carbon material with average particle size of 60-500nm;The carbon material is obtained by high-temperature heat treatment of lignin material under oxygen-free atmosphere, and the lignin material is the mixed solution of lignin or electrolytically treated lignin.The method of the present application can significantly improve the conversion rate of cyclic ketone, and the selectivity of diacid is high.

Description

TECHNICAL FIELD

[0001] The present application relates to a catalytic oxidation method of cyclic ketone. BACKGROUND

[0002] The scientific research of nanocarbon catalysis began in the 1990s. Studies have shown that the surface chemical properties of nanocarbon materials can be flexibly regulated, and saturated and unsaturated functional groups containing oxygen, nitrogen and other heteroatoms can be modified on the surface, so as to have certain acid-base properties and redox capacity, thereby being directly used as catalyst materials. Research and development of new catalytic materials related to nanocarbon materials have far-reaching theoretical significance and great potential application prospects in widening their applications in petrochemical industry, fine chemical industry and other fields.

[0003] Adipic acid, also known as fat acid, is an important organic dibasic acid, which can generate salt reaction, esterification reaction, amidation reaction, etc., and can be polymerized into high molecular polymer with dibasic amine or dihydric alcohol. Adipic acid is an important dibasic acid in industry, which plays an important role in chemical industry, organic synthesis industry, medicine, lubricant manufacturing, etc., and its output ranks second among all dibasic acids. Adipic acid is mainly used as a raw material for nylon 66 and engineering plastics, and is also used for producing various ester products, and is used as a raw material for polyurethane elastomer, acidifier for various foods and beverages, which sometimes is superior to citric acid and tartaric acid. Adipic acid is also a raw material for medicine, yeast purification, pesticides, adhesives, synthetic leather, synthetic dyes and perfumes. However, in the prior art, adipic acid is prepared by oxidation with nitric acid, which has serious corrosion and pollution. SUMMARY

[0004] The purpose of the present application is to provide a catalytic oxidation method of cyclic ketone. The method of the present application can realize catalytic oxidation of cyclic ketone under mild conditions, has high conversion rate of raw materials and high selectivity of target product diacid.

[0005] In order to achieve the above purpose, the present application provides a catalytic oxidation method of cyclic ketone, which comprises: contacting cyclic ketone and oxidant with a catalyst to perform an oxidation reaction, wherein the catalyst contains carbon material with an average particle size of 60-500 nm.

[0006] The carbon material is obtained by high-temperature heat treatment of lignin material under an oxygen-free atmosphere, and the lignin material is a mixed solution of lignin or electrolytically treated lignin.

[0007] Optionally, the average particle size of the carbon material is 80-360 nm.

[0008] Optionally, the high-temperature heat treatment of the lignin material in an oxygen-free atmosphere comprises: mixing the lignin with an ammonia source, and then high-temperature heat treating the mixture in an oxygen-free atmosphere to obtain the carbon material; the lignin and the ammonia source are mixed in a weight ratio of 100:(0.2-100), preferably 100:(1-20).

[0009] Optionally, the ammonia source is selected from one or more of aqueous ammonia, aqueous urea and hydrazine hydrate.

[0010] Optionally, the high-temperature heat treatment of the lignin material in an oxygen-free atmosphere comprises: high-temperature heat treating the lignin in an oxygen-free atmosphere containing ammonia to obtain the carbon material; the ammonia in the oxygen-free atmosphere containing ammonia has a mole fraction of 0.2-10%, preferably 0.6-5%.

[0011] Optionally, the high-temperature heat treatment has a temperature of 800-1500℃, a time of 1-12 hours and a pressure of 0.1-0.5MPa; preferably, the high-temperature heat treatment has a temperature of 1000-1300℃, a time of 2-8 hours and a pressure of 0.2-0.5MPa.

[0012] Optionally, the high-temperature heat treatment of the lignin material in an oxygen-free atmosphere comprises:

[0013] (1) placing a first conductive object and a second conductive object connected to the positive and negative poles of a direct current power source, respectively, in a mixed solution of lignin in a stirring state, and electrolyzing for 5-15 days under a voltage of 10-60V to obtain an electrolyzed mixed solution; wherein the first conductive object is a graphite rod;

[0014] (2) filtering and drying the electrolyzed mixed solution to obtain a lignin material, and high-temperature heat treating the lignin material at 850-1500℃ and 0.1-0.5MPa for 1-12 hours in an oxygen-free ammonia-containing atmosphere to obtain the carbon material, wherein the carbon material has an average particle size of 60-500nm; the ammonia in the oxygen-free ammonia-containing atmosphere has a mole fraction of 0.2-10%, preferably 0.6-5%.

[0015] Optionally, in step (1), the graphite rod has a diameter of 2-20mm and a length of 2-100cm; the second conductive object is an iron rod, an iron plate, a graphite rod, a graphite plate, a copper plate or a copper rod, preferably an iron rod, a graphite rod or a copper rod.

[0016] The mixed solution of the lignin contains water and optionally an inorganic base, wherein the water has a content of 65% by weight or more, preferably 70-95% by weight, and the inorganic base has a content of 0-20% by weight, preferably 1-20% by weight.

[0017] Optionally, the conditions of the oxidation reaction include: temperature of 50-150℃, time of 0.1-12 hours, and pressure of 0.1-5.0 MPa.

[0018] The oxidant is an oxygen-containing gas, preferably air or oxygen; and the molar ratio of the cyclic ketone to oxygen in the oxygen-containing gas is 1:(0.1-10).

[0019] Optionally, the amount of the catalyst is 20-500 mg, preferably 50-200 mg, based on 100 mL of the cyclic ketone, and the amount of the carbon material contained in the catalyst is calculated.

[0020] The cyclic ketone is a C6-C12 substituted or unsubstituted monocyclic ketone, and / or a C8-C16 substituted or unsubstituted bicyclic ketone.

[0021] By the above technical solution, the catalyst used in the method of the present application contains a carbon material obtained by high-temperature heat treatment of lignin material in an oxygen-free atmosphere, which has high reactivity when used in the selective oxidation reaction of cyclic ketones, and the selectivity of the target product is high.

[0022] Other features and advantages of the present application will be described in detail in the following specific embodiments. DETAILED DESCRIPTION

[0023] The specific embodiments of the present application are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0024] The present application provides a method for catalytic oxidation of cyclic ketones, which comprises: contacting cyclic ketones and an oxidant with a catalyst to perform an oxidation reaction, wherein the catalyst contains a carbon material with an average particle size of 60-500 nm; the carbon material is obtained by high-temperature heat treatment of lignin material in an oxygen-free atmosphere, and the lignin material is a mixture of lignin or electrolytically treated lignin.

[0025] The carbon material with a specific particle size used in the method of the present application has better catalytic activity, and can realize catalytic oxidation of cyclic ketones under mild conditions without using an initiator, with high conversion rate and high selectivity of the target product.

[0026] In an embodiment, the catalyst is a carbon material with a content of 100% by weight. In the present application, the oxygen-free atmosphere can be an inert gas atmosphere or an atmosphere with an oxygen content of less than 1% by volume, and the inert gas contained in the inert gas atmosphere can be one or more of nitrogen, argon and helium.

[0027] In one embodiment of the present application, the carbon material contained in the catalyst has an average particle size of 80-360 nm. The average particle size can be determined by methods well known to those skilled in the art, such as in a laser particle size analyzer, or by scanning electron microscopy or transmission electron microscopy. In one embodiment, the average particle size of the carbon material in the present application can be determined by TEM analysis of the carbon material, and the average value of the particle size is calculated by randomly selecting 100 particles in the TEM photograph, wherein the particle size is calculated based on the largest three-dimensional dimension of each carbon material particle (the distance between the two most distant points in the particle is the largest three-dimensional dimension). Carbon materials having a particle size in the above range have better catalytic performance, resulting in higher conversion of raw materials and selectivity of target products in the process of the present application.

[0028] In one embodiment of the present application, the carbon material is obtained by complete or partial carbonization of a lignin material, wherein the lignin material has an oxygen content of 5-30 wt%, preferably 10-25 wt%, and an average particle size of 50-1000 nm, preferably 100-300 nm.

[0029] In one embodiment of the present application, the high-temperature heat treatment of the lignin material in an oxygen-free atmosphere comprises mixing the lignin with an ammonia source, and then subjecting the mixture to high-temperature heat treatment in an oxygen-free atmosphere to obtain the carbon material. According to the present application, the weight ratio of the lignin to the ammonia source in the mixture can vary within a wide range. In one embodiment of the present application, the weight ratio of the lignin to the ammonia source in the mixture is 100:(0.2-100), preferably 100:(1-20).

[0030] In another embodiment of the present application, the high-temperature heat treatment of the lignin material in an oxygen-free atmosphere comprises subjecting the lignin to high-temperature heat treatment in an oxygen-free atmosphere containing ammonia to obtain the carbon material. According to the present application, the oxygen-free atmosphere containing ammonia can be obtained by directly introducing ammonia into the oxygen-free atmosphere, or by introducing aqueous ammonia into the oxygen-free atmosphere, and then heating the aqueous ammonia to form a gaseous state. The molar fraction of the ammonia in the oxygen-free atmosphere containing ammonia can vary within a wide range, for example, it can be 0.2-10%, preferably 0.6-5%. The above methods of introducing ammonia are beneficial to the preparation of carbon materials with better performance, thereby further improving the conversion of raw materials and the selectivity of target products in the process of the present application.

[0031] According to the present application, the ammonia source can be a substance containing ammonia, for example, it can include but is not limited to one or more of aqueous ammonia, aqueous urea, and hydrazine hydrate. The present application does not have special limitations on the source of lignin.

[0032] According to the present application, the high-temperature heat treatment is carried out in a device with heat treatment effect commonly used by those skilled in the art, such as a muffle furnace or a tube furnace. In one embodiment of the present application, the conditions of the high-temperature heat treatment include a temperature of 800-1500°C, a time of 1-12 hours, and a pressure of 0.1-0.5 MPa; preferably, the temperature is 1000-1300°C, the time is 2-8 hours, and the pressure is 0.2-0.5 MPa.

[0033] In one embodiment of the present application, the high-temperature heat treatment of the lignin material in an oxygen-free atmosphere includes: (1) placing a first conductive object and a second conductive object connected to the positive and negative poles of a direct current power source, respectively, in a mixed solution of lignin in a stirring state, electrolyzing for 5-15 days under a voltage of 10-60 V to obtain an electrolyzed mixed solution; wherein the first conductive object is a graphite rod; (2) filtering and drying the electrolyzed mixed solution to obtain a lignin material, and high-temperature heat treating the obtained lignin material solid at 850-1500°C and 0.1-0.5 MPa for 1-12 hours in an oxygen-free ammonia-containing atmosphere to obtain the carbon material, wherein the average particle size of the carbon material is 60-500 nm, and the molar fraction of ammonia in the oxygen-free ammonia-containing atmosphere is 0.2-10%, preferably 0.6-5%.

[0034] In one embodiment of the present application, the size of the graphite rod in step (1) is not limited, and in one embodiment, the diameter of the graphite rod is 2-20 mm and the length is 2-100 cm. The specific type of the second conductive object is not limited, as long as it is an electrically conductive object, and there is no requirement for the shape, such as a common rod or plate. Preferably, the second conductive object is an iron rod, an iron plate, a graphite rod, a graphite plate, a copper plate, or a copper rod, more preferably an iron rod, a graphite rod, or a copper rod, and further preferably a graphite rod matching the size of the first conductive object. When electrolysis is performed, a certain distance can be maintained between the first conductive object and the second conductive object, and the distance can vary within a large range, such as 1-20 cm.

[0035] According to the present application, the mixed solution of lignin contains solvent water, and in one embodiment of the present application, the water content in the mixed solution of lignin is 65% by weight or more, preferably 70-95% by weight, and more preferably the mixed solution of lignin further contains an inorganic base, such as sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia water, etc., preferably ammonia water, and the mass concentration of the inorganic base is not limited, such as 1-20% by weight. The amount of the mixed solution of lignin is not specially limited and can be adjusted according to the material and size of the conductive object and the electrolysis conditions.

[0036] In one embodiment of the present application, the conditions of the oxidation reaction include a temperature of 50-150°C, a time of 0.1-12 hours, and a pressure of 0.1-5.0 MPa; preferably, a temperature of 60-120°C, a time of 2-8 hours, and a pressure of 0.5-2.5 MPa. The oxidation reaction can be carried out under stirring to make the reaction more complete.

[0037] According to the present application, the oxidation reaction can be carried out in any conventional catalytic reactor, such as a batch tank reactor, a fixed bed reactor, a moving bed reactor, a suspended bed reactor, or a slurry bed reactor. In one embodiment, the catalytic oxidation reaction is carried out in a slurry bed reactor, and the amount of catalyst used can be 20-500 mg, preferably 50-200 mg, based on 100 mL of the cyclic ketone, in terms of the carbon material contained in the catalyst. In another embodiment, the catalytic oxidation reaction is carried out in a fixed bed reactor, and the weight hourly space velocity of the cyclic ketone can be 0.1-50 h -1 , preferably 0.5-25 h -1 , more preferably 1-10 h -1 .

[0038] According to the present application, the conditions of the oxidation reaction include a temperature of 50-150°C, a time of 1-12 hours, and a pressure of 0.1-5.0 MPa; preferably, a temperature of 60-120°C, a time of 2-8 hours, and a pressure of 0.5-2.5 MPa. The oxidation reaction can be carried out under stirring to make the reaction more complete.

[0039] According to the present application, the oxidizing agent is one conventionally used by those skilled in the art, and in one embodiment of the present application, the oxidizing agent is an oxygen-containing gas, preferably air or oxygen. The molar ratio of the cyclic ketone to oxygen in the oxygen-containing gas can vary within a wide range, for example, the molar amount of the oxygen-containing gas can be 0.1-10 times the theoretical amount of oxygen required for the oxidation of the cyclic ketone to the desired product. In one embodiment, the molar ratio of the cyclic ketone to oxygen in the oxygen-containing gas is 1:(0.1-10).

[0040] In one embodiment of the present application, the cyclic ketone is a substituted or unsubstituted monocyclic ketone having 6-12 carbon atoms, and / or a substituted or unsubstituted bicyclic ketone having 8-16 carbon atoms. The unsubstituted cyclic ketone can be, for example, cyclohexanone, cycloheptanone, cyclooctanone, bicyclohexanone, etc., and is preferably cyclohexanone. The substituent of the substituted cyclic ketone can be, for example, a methyl group, an ethyl group, a propyl group, a halogen, etc., and the substituted cyclic ketone can be, for example, methylcyclohexanone, chlorocyclohexanone, bromocyclohexanone, etc.

[0041] According to the present invention, in order to improve the degree of mixing between the reaction materials, the method may further include: the oxidation reaction is carried out in the presence of a solvent, and the solvent may be various liquid substances that can promote the dissolution of the reactants. Generally, the solvent may be a C1-C6 alcohol and a C2-C6 nitrile, or a combination of two or three thereof. Specific examples of the solvent may include, but are not limited to, methanol, ethanol, n-propanol, isopropanol, and acetonitrile. Preferably, the solvent is a C1-C6 alcohol. More preferably, the solvent is methanol. The amount of the solvent can be selected according to actual needs and will not be described in detail herein.

[0042] The present invention is further illustrated below by way of examples, but the present invention is not limited thereto.

[0043] The reagents used in the present invention are all commercially available analytically pure reagents.

[0044] In the preparation example, the average particle size of the carbon material was obtained by TECHNAIG 2 The measurement was carried out using an F20 (200kV) transmission electron microscope. The test conditions were as follows: an accelerating voltage of 20kV, sample preparation by the suspension method, the sample was placed in a 2mL glass bottle, dispersed with anhydrous ethanol, and shaken evenly. A drop was taken with a dropper and dropped onto a sample net with a diameter of 3mm. After drying, the sample was placed in a sample injector and then inserted into an electron microscope for observation. 100 particles were randomly selected for particle size statistics.

[0045] The preparation examples are used to illustrate the carbon materials and preparation methods thereof according to the present invention, and the preparation comparative examples are used to illustrate unmodified carbon materials different from those of the present invention.

[0046] Preparation Example 1

[0047] (1) under normal pressure and stirring, in a beaker, add 500mL of ammonia solution with a mass concentration of 2%, add 50g of lignin (oxygen content is 21% by weight, and average particle size is 260nm), an anode graphite rod (diameter 12mm, length 35cm) and a cathode graphite rod (diameter 12mm, length 35cm) are placed therein, the distance between the anode graphite rod and the cathode graphite rod is kept at 10cm, the anode graphite rod is connected to the positive pole of a DC power supply and the cathode graphite rod is connected to the negative pole of the DC power supply, apply a voltage of 60V and carry out electrolysis 5 days to obtain an electrolytic mixture;

[0048] (2) The electrolytic mixture was filtered and dried at 120°C for 12 hours. The dried solid was subjected to high-temperature heat treatment at a pressure of 0.12 MPa and a temperature of 1100°C for 3 hours in a mixed atmosphere of nitrogen and ammonia (the molar ratio of nitrogen to ammonia was 95:5) to obtain a carbon material A1 with an average particle size of 80 nm.

[0049] Preparation Example 2

[0050] Carbon material A2 was prepared in the same manner as in Preparation Example 1, except that in step (2), the temperature of the high-temperature heat treatment was 800°C and the time was 12 hours. The average particle diameter of A2 was 65 nm.

[0051] Preparation Example 3

[0052] Carbon material A3 was prepared in the same manner as in Preparation Example 1, except that in step (2), the temperature of the high-temperature heat treatment was 1350°C and the time was 1 hour. The average particle diameter of A3 was 160 nm.

[0053] Preparation Example 4

[0054] Carbon material A4 was prepared in the same manner as in Preparation Example 1, except that in step (2), the high-temperature heat treatment was performed only in a nitrogen atmosphere, i.e., ammonia was not introduced during the high-temperature heat treatment. The average particle diameter of A4 was 80 nm.

[0055] Preparation Example 5

[0056] Carbon material A5 was prepared in the same manner as in Preparation Example 1, except that in step (1), distilled water was used instead of the 2% ammonia aqueous solution. The average particle diameter of A5 was 90 nm.

[0057] Preparation Example 6

[0058] Carbon material A6 was prepared in the same manner as in Preparation Example 1, except that the lignin was subjected to the high-temperature heat treatment in an atmosphere formed by introducing ammonia into a nitrogen atmosphere (molar ratio of nitrogen to ammonia: 95:5) at a pressure of 0.12 MPa and a temperature of 1100°C for 3 hours. The average particle diameter of A5 was 420 nm.

[0059] Preparation Example 7

[0060] Modified nanocarbon-based material A7 was prepared in the same manner as in Preparation Example 1, except that in step (2), the molar ratio of nitrogen to ammonia during the high-temperature heat treatment was 92:8. The average particle diameter of A7 was 60 nm.

[0061] Preparation Example 8

[0062] Modified nanocarbon-based material A8 was prepared in the same manner as in Preparation Example 1, except that in step (2), the dried solid was mixed with a urea aqueous solution, the mixture was placed in a tube furnace, and the mixture was subjected to the high-temperature heat treatment at a pressure of 0.12 MPa and a temperature of 1100°C for 3 hours, to obtain carbon material A8, which had an average particle diameter of 75 nm.

[0063] Preparation Example 9

[0064] Under an atmosphere of nitrogen gas, 50 g of lignin (oxygen content: 21% by weight, average particle diameter: 260 nm) was subjected to high-temperature heat treatment at a pressure of 0.12 MPa and a temperature of 1100°C for 3 hours under an atmosphere in which ammonia gas was introduced into the atmosphere of nitrogen gas (molar ratio of nitrogen gas to ammonia gas: 95:5) to obtain carbon material A9 having an average particle diameter of 260 nm.

[0065] Preparation Example 10

[0066] Carbon material was prepared in the same manner as in Preparation Example 9, except that ammonia gas was not introduced into the atmosphere of nitrogen gas, and only a nitrogen gas atmosphere was provided, to obtain carbon material A10 having an average particle diameter of 420 nm.

[0067] Preparation Comparative Example 1

[0068] Carbon material DB1 was prepared in the same manner as in Preparation Example 1, except that in step (2), the electrolytic mixed solution was subjected to freeze drying to obtain carbon material, and was not subjected to high-temperature heat treatment. DB1 had an average particle diameter of 25 nm.

[0069] Examples are used to illustrate a method for catalytically oxidizing cyclic ketones using the present application. Preparation Comparative Example 1 is used to illustrate a method for catalytically oxidizing cyclic ketones that is different from the present application.

[0070] In the following examples and comparative examples, gas chromatography (GC: Agilent, 7890A) and gas chromatography-mass spectrometry (GC-MS: Thermo Fisher Trace ISQ) were used to analyze the oxidation products.

[0071] On this basis, the following formulas were used to calculate the raw material conversion rate and the target product selectivity, respectively:

[0072] Cyclic ketone conversion rate % = (molar amount of cyclic ketone added before the reaction - molar amount of cyclic ketone remaining after the reaction) / molar amount of cyclic ketone added before the reaction x 100%;

[0073] Target product selectivity % = molar amount of target product generated after the reaction / molar amount of cyclic ketone added before the reaction x 100%.

[0074] Example 1

[0075] Into a 250 mL high-pressure reaction kettle, 55 mg of carbon material A1 was added as catalyst and 100 mL of cyclohexanone was added and continuously stirred. Oxygen was introduced (molar ratio of cyclohexanone to oxygen was 1:6), and the mixture was stirred at 130°C and 2.0 MPa for 5 hours of oxidation reaction, and then sampled after cooling and pressure relief, centrifuged and filtered to separate the carbon material, and the oxidation product was analyzed, and the results are shown in Table 1.

[0076] Example 2-10

[0077] Examples 2-10 were respectively carried out by using the same method as Example 1 for catalytic oxidation of cyclohexanone, except that Example 2 used carbon material A2 as catalyst, Example 3 used carbon material A3 as catalyst, Example 4 used carbon material A4 as catalyst, Example 5 used carbon material A5 as catalyst, Example 6 used carbon material A6 as catalyst, Example 7 used carbon material A7 as catalyst, Example 8 used carbon material A8 as catalyst, Example 9 used carbon material A9 as catalyst, and Example 10 used carbon material A10 as catalyst.

[0078] Example 11

[0079] Catalytic oxidation of cyclohexanone was carried out by using the same method as Example 1, except that 40 mg of carbon material A1 was added as catalyst and 100 mL of cyclohexanone was added into a 250 mL high-pressure reaction kettle and continuously stirred by magnetic force.

[0080] Comparative Example 1

[0081] Catalytic oxidation of cyclohexanone was carried out by using the same method as Example 1, except that the nanomaterial DB1 prepared in Comparative Example 1 was used as catalyst.

[0082] Comparative Example 2

[0083] Catalytic oxidation of cyclohexanone was carried out by using the same method as Example 1, except that untreated lignin was used as catalyst.

[0084] Table 1

[0085] Catalyst No. Cyclohexanone conversion, % Adipic acid selectivity, % Example 1 A1 81 96 Example 2 A2 78 89 Example 3 A3 75 86 Example 4 A4 76 81 Example 5 A5 70 84 Example 6 A6 74 85 Example 7 A7 67 78 Example 8 A8 72 81 Example 9 A9 59 77 Example 10 A10 51 70 Example 11 A1 64 73 Comparative Example 1 DB1 30 48 Comparative Example 2 Lignin 7 25

[0086] As can be seen from Table 1, the method of the present application can significantly improve the conversion rate of cyclohexanone and the selectivity of adipic acid is high.

[0087] The above describes the preferred embodiments of the present application in detail, but the present application is not limited to the specific details in the above-described embodiments, and within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, and these simple modifications all belong to the protection scope of the present application.

[0088] It should be further noted that each of the various technical features described in the above embodiments can be combined with any other technical features in any suitable manner, and the present application shall be deemed to disclose all possible combinations thereof, without causing unnecessary repetition.

[0089] Furthermore, any combination of the various embodiments of the present application can be made, as long as it does not deviate from the spirit of the present application, and it shall be deemed to be disclosed by the present application.

Claims

1. A catalytic oxidation method for cyclic ketones, the method comprising: The cyclic ketone and the oxidant are contacted with a catalyst to carry out an oxidation reaction, wherein the catalyst comprises a carbon material having an average particle size of 60-500 nm; the cyclic ketone is a C6-C12 substituted or unsubstituted monocyclic ketone, and / or a C8-C16 substituted or unsubstituted bicyclic ketone; The carbon material is obtained by subjecting a lignin material to a high-temperature heat treatment in an oxygen-free atmosphere, wherein the lignin material is lignin or a mixed solution of lignin treated by electrolysis; The high-temperature heat treatment of the lignin material in an oxygen-free atmosphere comprises: subjecting the lignin to a high-temperature heat treatment in an oxygen-free atmosphere containing ammonia to obtain the carbon material; the molar fraction of ammonia in the oxygen-free atmosphere containing ammonia is 0.2-10%; the high-temperature heat treatment conditions are: a temperature of 800-1500°C, a time of 1-12 hours, and a pressure of 0.1-0.5 MPa; or, The high-temperature heat treatment of the lignin material in an oxygen-free atmosphere comprises: (1) placing a first conductive object and a second conductive object connected to the positive electrode and the negative electrode of a DC power supply, respectively, in a stirred lignin mixture, and electrolyzing the mixture at a voltage of 10-60 V for 5-15 days to obtain an electrolytic mixture; wherein the first conductive object is a graphite rod; (2) After filtering and drying the electrolytic mixture, the obtained solid is subjected to high-temperature heat treatment at 850-1500° C. and 0.1-0.5 MPa in an oxygen-free ammonia-containing atmosphere for 1-12 hours to obtain the carbon material, wherein the average particle size of the carbon material is 60-500 nm; the molar fraction of ammonia in the oxygen-free ammonia-containing atmosphere is 0.2-10%.

2. The method according to claim 1, wherein The average particle size of the carbon material is 80-360 nm.

3. The method according to claim 1, wherein The molar fraction of ammonia in the oxygen-free atmosphere containing ammonia is 0.6-5%.

4. The method according to claim 1, wherein The conditions for subjecting the lignin to the high-temperature heat treatment in an oxygen-free atmosphere containing ammonia are: a temperature of 1000-1300° C., a time of 2-8 hours, and a pressure of 0.2-0.5 MPa.

5. The method according to claim 1, wherein The molar fraction of ammonia in the oxygen-free ammonia-containing atmosphere is 0.6-5%.

6. The method according to claim 1, wherein In step (1), the diameter of the graphite rod is 2-20 mm and the length is 2-100 cm; the second conductive object is an iron rod, an iron plate, a graphite rod, a graphite plate, a copper plate or a copper rod; The lignin mixture contains water and optionally an inorganic base, wherein the water content is greater than 65% by weight and the inorganic base content is 0-20% by weight.

7. The method according to claim 6, wherein: The second conductive object is an iron rod, a graphite rod or a copper rod; The content of water is 70-95% by weight, and the content of the inorganic base is 1-20% by weight.

8. The method according to claim 1, wherein The oxidation reaction conditions are: temperature of 50-150°C, time of 0.1-12 hours, and pressure of 0.1-5.0 MPa; The oxidant is an oxygen-containing gas; the molar ratio of the cyclic ketone to the oxygen in the oxygen-containing gas is 1:(0.1-10).

9. The method according to claim 8, wherein The oxidant is air or oxygen.

10. The method according to claim 1, wherein Based on 100 mL of the cyclic ketone and the carbon material contained in the catalyst, the amount of the catalyst used is 20-500 mg.

11. The method according to claim 10, wherein: Based on 100 mL of the cyclic ketone and the carbon material contained in the catalyst, the amount of the catalyst used is 50-200 mg.