Mesoporous carbon composite material and preparation method and application thereof

Abstract

The invention relates to a mesoporous carbon composite material as well as a preparation method and application thereof. The mesoporous carbon composite material comprises nitrogen-doped hollow mesoporous carbon and metal single atoms loaded on the nitrogen-doped hollow mesoporous carbon. The invention also provides a preparation method of the mesoporous carbon composite material, which comprises the following steps: adding 3-aminophenol and formaldehyde into alkaline water, then adding into a mixed solution of an organic solvent and alkali, then sequentially adding hexadecyl trimethyl ammonium bromide, ethyl silicate and N, N-dimethylformamide, and calcining the product in a nitrogen atmosphere to obtain the mesoporous carbon composite material. And then mixing with a mixed solution of copper acetylacetonate and an organic solvent, adding into an acetone solution, carrying out heating reaction after ultrasonic treatment, and calcining in a nitrogen atmosphere to obtain the mesoporous carbon composite material. The invention also provides application of the mesoporous carbon composite material as a catalyst. The problem that an existing catalyst is low in degradation efficiency is solved, and the problem that an existing catalyst is large in dosage is also solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalytic materials, in particular to a mesoporous carbon composite material and a preparation method and application thereof. BACKGROUND

[0002] In recent years, antibiotics have been widely used in the fields of human health care, livestock production and aquaculture. However, the metabolism of animals to antibiotics is not complete, resulting in a large amount of unmetabolized antibiotics entering the environment with excrement and retaining their biological activity. These antibiotics entering environmental media such as water bodies and soils will force the production and spread of antibiotic resistance genes (ARGs) in bacterial communities. The widespread spread of ARGs may lead to the emergence of super-resistant bacteria, thereby posing a great threat to public health. In addition, the accumulation of antibiotics in the water environment will inhibit the growth and development of aquatic organisms, and may ultimately affect human health through the bioaccumulation of the food chain. In view of its potential harm, antibiotics have been listed in the list of key control new pollutants, and its treatment and control have become a major problem to be solved by scientific researchers.

[0003] As an emerging environmental remediation technology, advanced oxidation processes (AOPs) can effectively mineralize most pollutants by generating strong oxidizing free radicals to degrade organic pollutants, and decompose them into harmless substances such as carbon dioxide, water and inorganic salts. However, the free radicals (such as hydroxyl radicals and sulfate radicals) generated in the advanced oxidation process have an ultra-short lifetime (10 -6 ~10 -9 s), which greatly hinders the full contact and reaction of free radicals with organic pollutants, thereby limiting its application effect in heterogeneous reactions. In addition, the existing catalysts for activating persulfate to degrade antibiotics have problems such as large dosage and low degradation efficiency, which further restricts their application in actual environmental governance. Therefore, developing a new type of catalyst that can efficiently activate persulfate, improve the utilization rate of free radicals and has high degradation efficiency has important practical significance for solving the problem of antibiotic pollution. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a mesoporous carbon composite material and a preparation method and application thereof, so as to solve the problem of low degradation efficiency of existing catalysts, and also solve the problem of large dosage of existing catalysts.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows: A mesoporous carbon composite material comprises nitrogen-doped hollow mesoporous carbon and metal monatomic atoms loaded on the nitrogen-doped hollow mesoporous carbon.

[0006] According to the above technical means, by loading metal monatomic atoms on nitrogen-doped hollow mesoporous carbon as a carrier, because the specific surface area of nitrogen-doped hollow mesoporous carbon is large and the defect sites are increased, the loading amount and stability of copper monatomic atoms can be improved, so that when it is used as a catalyst, the ability of the material to activate persulfate can be enhanced, and then the antibiotics in the wastewater can be efficiently degraded. The problem of low degradation efficiency of the existing catalyst is solved, and the problem of large amount of the existing catalyst is also solved.

[0007] Preferably, the metal monatomic atom is a copper monatomic atom.

[0008] The present application also provides a preparation method of the mesoporous carbon composite material, comprising the following steps: S1, adding 3-amino phenol and formaldehyde into alkaline water, reacting to obtain a first product; S2, adding the first product into a mixed solution of an organic solvent and a base, then sequentially adding hexadecyl trimethyl ammonium bromide and ethyl silicate, mixing uniformly, then adding N,N-dimethyl formamide, centrifuging, drying to obtain a solid product; S3, calcining the solid product in a nitrogen atmosphere to obtain nitrogen-doped hollow mesoporous carbon; S4, adding a mixed solution of acetylacetone copper and an organic solvent, and the nitrogen-doped hollow mesoporous carbon into a solution of acetone to obtain a first mixed solution; S5, ultrasonically treating the first mixed solution and then heating to react to obtain a second product; S6, heating the second product to a preset temperature in a nitrogen atmosphere, and constant temperature calcining to obtain a mesoporous carbon composite material in the form of Cu-N3, that is, nitrogen-doped hollow mesoporous carbon loaded with metal monatomic atoms (N-HCMS@Cu-SACS).

[0009] By using 3-amino phenol and formaldehyde as precursors, a condensation reaction in an alkaline environment forms a first product, and then a mixed solution of an organic solvent and a base is further reacted to introduce hexadecyl trimethyl ammonium bromide and ethyl silicate, forming a nitrogen-doped mesoporous carbon precursor with a hollow structure. By calcining in a nitrogen atmosphere, the structure and performance of the material are further optimized. Through the composite reaction of acetylacetone copper and nitrogen-doped hollow mesoporous carbon, uniform loading of copper monatomic atoms is achieved. This structure not only increases the number of active sites of the catalyst, but also enhances the mass transfer efficiency and reaction activity through nitrogen doping and hollow mesoporous structure. Nitrogen doping provides more active sites, hollow mesoporous structure increases the specific surface area and mass transfer efficiency, and uniform dispersion of copper monatomic atoms further improves the catalytic efficiency. Therefore, the mesoporous carbon composite material of the present application exhibits higher degradation efficiency and lower catalyst dosage in the catalytic degradation reaction.

[0010] Preferably, the base is selected from aqueous ammonia.

[0011] Preferably, the organic solvent is selected from anhydrous ethanol.

[0012] Preferably, the volume ratio of base to water in the aqueous base is 0.1-0.3:20-30.

[0013] Preferably, the water is deionized water and / or ultrapure water.

[0014] Preferably, the 3-amino phenol, the formaldehyde, the cetyltrimethylammonium bromide, the ethyl silicate, and the N,N-dimethylformamide are 0.1-0.3 g:0.1-0.15 mL:0.1-0.3 g:5-10 mL:30-50 mL by g:mL:g:mL:mL.

[0015] Preferably, the volume ratio of organic solvent to base in the mixed solution of organic solvent and base is 20-30:0.5-1.5.

[0016] Preferably, the mass ratio of the copper acetylacetonate to the nitrogen-doped hollow mesoporous carbon is 0.15-0.6:0.1-0.4.

[0017] Preferably, the temperature for calcination in a nitrogen atmosphere is 550-800 ℃, and the time is 2-5 h.

[0018] Preferably, the preset temperature is 600-800 ℃, the time for constant temperature calcination is 3-6 h, the heating mode for temperature increase in a nitrogen atmosphere is programmed temperature increase, and the temperature increase rate for programmed temperature increase is 5 ℃ / min.

[0019] Preferably, the time for ultrasonic treatment is 4 h, the temperature for heating reaction is 60-80 ℃, and the time is 6-8 h.

[0020] The application also provides the use of the mesoporous carbon composite material prepared by the preparation method as a catalyst.

[0021] Preferably, the mesoporous carbon composite material as a catalyst is used for catalyzing the degradation of antibiotics in wastewater.

[0022] Preferably, the mesoporous carbon composite material as a catalyst is used for catalyzing the degradation of antibiotics in wastewater by persulfate.

[0023] Preferably, the persulfate is selected from sodium persulfate.

[0024] Preferably, the antibiotics include at least one of tetracycline, oxytetracycline hydrochloride, and sulfamethoxazole.

[0025] Preferably, the mass ratio of the persulfate salt to the mesoporous carbon composite material is 1:0.5~1.5.

[0026] Preferably, when the mass ratio of the antibiotic, the persulfate salt (PDS) and the mesoporous carbon composite material in the sewage is 0.04~0.2:1:0.5~1.5, the time for reducing the antibiotic in the sewage to 0 is 12~20 min.

[0027] Preferably, the mesoporous carbon composite material is used as a catalyst for a method of catalyzing the persulfate salt to degrade the antibiotic in the sewage, which comprises the following steps: The persulfate salt and the mesoporous carbon composite material are added into the sewage containing the antibiotic, and after being uniformly mixed, the reaction is carried out under normal temperature and pressure and in the dark to realize the removal of the antibiotic in the sewage.

[0028] The mesoporous carbon composite material of the present application is used as a catalyst for catalyzing the persulfate salt to degrade the antibiotic in the sewage, which directly adds the mesoporous carbon composite material and the persulfate salt into the sewage containing the antibiotic, uniformly mixes them, and then carries out the reaction under normal temperature and pressure and in the dark, so that the removal of the antibiotic in the sewage can be realized. Not only the cumbersome operation of the traditional persulfate salt catalyst which needs to be irradiated by ultraviolet light to realize the catalytic action is avoided, but also the removal efficiency is greatly improved.

[0029] The present application has the following advantages: The mesoporous carbon composite material of the present application, by ingeniously using the nitrogen-doped hollow mesoporous carbon to load copper monatomic atoms, effectively improves the stability of the catalyst, thereby improving the degradation efficiency of the catalyst and reducing the usage amount of the catalyst.

[0030] The preparation method of the mesoporous carbon composite material of the present application, by using 3-amino phenol and formaldehyde as precursors, carries out a condensation reaction in an alkaline environment to form a first product, and then further reacts with a mixed solution of an organic solvent and a base to introduce hexadecyl trimethyl ammonium bromide and ethyl silicate, thereby forming a nitrogen-doped mesoporous carbon precursor with a hollow structure. By calcining under a nitrogen atmosphere, the structure and performance of the material are further optimized. By a composite reaction of copper acetylacetonate and the nitrogen-doped hollow mesoporous carbon, uniform loading of copper monatomic atoms is realized.

[0031] The mesoporous carbon composite material of the present application is used as a catalyst for catalyzing the persulfate salt to degrade the antibiotic in the sewage, and the catalyst shows excellent performance in activating PDS to remove tetracycline, with a removal rate of 83 % in 4 min and complete degradation in 8 min. It has application value in the field of catalytic materials and antibiotic wastewater treatment technology. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The figure is the degradation test result of the antibiotic TC in the sewage. Figure 2 Figure 8 is a graph of the degradation of antibiotic TC in wastewater with different catalyst dosages; Figure 3 Figure 9 is a graph of the degradation of antibiotic TC in wastewater with different initial concentrations of TC; Figure 4 Figure 10 is a graph of the degradation of antibiotic TC in wastewater with different pH values; Figure 5 Figure 11 is a graph of the degradation of antibiotic TC in wastewater with catalyst recycling; Figure 6 Figure 12 is a graph of the degradation of antibiotic TC in wastewater with increased quenching agent; Figure 7 Figure 13 is a graph of the degradation of antibiotic TC in different water matrices; Figure 8 Figure 14 is a graph of the degradation of different antibiotic wastewater by the catalyst; Figure 9 Figure 15 is a SEM image of N-HCMS and N-HCMS@Cu-SAC obtained in Example 1; Figure 10 Figure 16 is an XRD image of N-HCMS@Cu-SAC obtained in Example 1; Figure 11 Figure 17 is a HAADF-STEM image of N-HCMS@Cu-SAC obtained in Example 1; Figure 12 Figure 18 is an EPR test result of the catalyst. DETAILED DESCRIPTION

[0033] Other advantages and benefits of the present application will become apparent to those skilled in the art upon consideration of the disclosure or can be learned by practice of the application. The present application can be realized and achieved by means other than as specifically described herein and various modifications and changes in detail can be made therein by those skilled in the art without departing from the spirit and scope of the application. It is to be understood that the foregoing preferred embodiments are merely illustrative of the present application and are not intended to limit the scope of the present application.

[0034] The present application provides a mesoporous carbon composite material, a preparation method thereof and an application thereof, to solve the problem of low degradation efficiency of existing catalysts, and can also solve the problem of large amount of existing catalysts, improve the stability of metal single-atom catalysts, reduce the leaching rate of metal ions, enhance the ability to activate persulfate, and maintain high catalytic performance in various environments.

[0035] The mesoporous carbon composite material comprises nitrogen-doped hollow mesoporous carbon and metal single atoms loaded on the nitrogen-doped hollow mesoporous carbon.

[0036] In some embodiments, the metal monatom is a copper monatom.

[0037] In some embodiments, a method for preparing the mesoporous carbon composite material is also provided, comprising the following steps: S1, adding 3-amino phenol and formaldehyde into alkaline water, reacting to obtain a first product; S2, adding the first product into a mixed solution of an organic solvent and a base, then sequentially adding hexadecyl trimethyl ammonium bromide and ethyl silicate, mixing uniformly, then adding N,N-dimethyl formamide, centrifuging, drying to obtain a solid product; S3, calcining the solid product in a nitrogen atmosphere to obtain nitrogen-doped hollow mesoporous carbon; S4, mixing a mixed solution of copper acetylacetonate and an organic solvent, nitrogen-doped hollow mesoporous carbon and water, then adding into a solution of acetone to obtain a first mixed solution; S5, ultrasonicating the first mixed solution and then heating to react to obtain a second product; S6, heating the second product to a preset temperature in a nitrogen atmosphere, and constant temperature calcining to obtain a Cu-N3 form existing mesoporous carbon composite material, i.e. nitrogen-doped hollow mesoporous carbon loaded with metal monatom (N-HCMS@Cu-SACS).

[0038] In some embodiments, the base is selected from ammonia water.

[0039] In some embodiments, the organic solvent is selected from anhydrous ethanol.

[0040] In some embodiments, in the alkaline water, the volume ratio of the base to water is 0.1-0.3:20-30.

[0041] In some embodiments, the water is deionized water and / or ultrapure water.

[0042] In some embodiments, the 3-amino phenol, the formaldehyde, the hexadecyl trimethyl ammonium bromide, the ethyl silicate and the N,N-dimethyl formamide are 0.1-0.3 g:0.1-0.15 mL:0.1-0.3 g:5-10 mL:30-50 mL in terms of g:mL:g:mL:mL.

[0043] In some embodiments, in the mixed solution of the organic solvent and the base, the volume ratio of the organic solvent to the base is 20-30:0.5-1.5.

[0044] In some embodiments, the mass ratio of the copper acetylacetonate to the nitrogen-doped hollow mesoporous carbon is 0.15-0.6:0.1-0.4.

[0045] In some embodiments, the temperature for calcining in the nitrogen atmosphere is 550-800 ℃, and the time is 2-5 h.

[0046] In some embodiments, the preset temperature is 600-800 DEG C, the time for constant temperature calcination is 3-6 h, the temperature rising mode in the nitrogen atmosphere is programmed temperature rising, and the temperature rising rate of the programmed temperature rising is 5 DEG C / min.

[0047] In some embodiments, the time for ultrasonic treatment is 4 h, the temperature for heating reaction is 60-80 DEG C, and the time is 6-8 h.

[0048] In some embodiments, the application also provides the use of the mesoporous carbon composite material prepared by the preparation method as a catalyst.

[0049] In some embodiments, the mesoporous carbon composite material is used as a catalyst for catalyzing the degradation of antibiotics in wastewater.

[0050] In some embodiments, the mesoporous carbon composite material is used as a catalyst for catalyzing the degradation of antibiotics in wastewater.

[0051] In some embodiments, the persulfate is selected from sodium persulfate; In some embodiments, the antibiotics include at least one of tetracycline, oxytetracycline hydrochloride, and sulfamethoxazole; In some embodiments, the mass ratio of the persulfate to the mesoporous carbon composite material is 1:0.5-1.5; In some embodiments, when the mass ratio of the antibiotics, the persulfate (PDS), and the mesoporous carbon composite material in the wastewater is 0.04-0.2:1:0.5-1.5, the time for reducing the antibiotics in the wastewater to 0 is 12-20 min.

[0052] In some embodiments, the mesoporous carbon composite material is used as a catalyst for catalyzing the degradation of antibiotics in wastewater by a method comprising the following steps: The persulfate and the mesoporous carbon composite material are added to wastewater containing antibiotics, mixed uniformly, and then reacted under normal temperature and pressure and in the dark to remove the antibiotics in the wastewater.

[0053] The mesoporous carbon composite material is used as a catalyst for catalyzing the degradation of antibiotics in wastewater by the method, which comprises the following steps: the mesoporous carbon composite material and the persulfate are directly added to wastewater containing antibiotics, mixed uniformly, and then reacted under normal temperature and pressure and in the dark to remove the antibiotics in the wastewater, which not only avoids the complicated operation of the traditional persulfate catalyst which needs to be irradiated by ultraviolet light to realize the catalytic effect, but also greatly improves the removal efficiency.

[0054] In order to make the technical problems, technical solutions and beneficial effects solved by the present application clearer, the mesoporous carbon composite material, the preparation method and application thereof will be further described in detail below in combination with specific embodiments and drawings. Obviously, the described specific embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application. Based on the specific embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0055] Unless otherwise specified in the specific embodiments, the technology or conditions are carried out according to the technology or conditions described in the literature in the art or according to the product instructions. Unless otherwise specified, the reagents or instruments used are conventional products that can be obtained by purchase in the market.

[0056] Embodiment 1 A preparation method of a mesoporous carbon composite material, comprising the following steps: S1, mixing 0.1 mL of ammonia water with 30 mL of deionized water, stirring for more than 1 h, then adding 0.1 g of 3-aminophenol, continuously stirring for 30 min, then adding 0.14 mL of formaldehyde solution, stirring for 30 min at a temperature of 30 ℃, to obtain a first product; S2, adding the first product prepared in S1 to a mixed solution of 50 mL of deionized water, 20 mL of anhydrous ethanol and 1 mL of ammonia water, stirring for 5 min, then adding 0.2 g of cetyltrimethylammonium bromide, then adding 10 mL of ethyl silicate dropwise, mixing uniformly, reacting for 10 h, then adding 35 mL of N,N-dimethylformamide to dissolve the oligomer, collecting the precipitated product by centrifugation, then drying the precipitated product at a temperature of 60 ℃ for 8 h to obtain a solid product; S3, calcining the solid product obtained in S2 in a nitrogen (N2) atmosphere at a temperature of 800 ℃ for 3 h to realize carbonization and etching, to obtain nitrogen-doped hollow mesoporous carbon (i.e., N-HMCS); S4, adding 0.3 g of copper acetylacetonate to 20 mL of anhydrous ethanol, then adding 0.2 g of nitrogen-doped hollow mesoporous carbon, then adding 50 mL of acetone, stirring uniformly to obtain a first mixed solution; S5, ultrasonic treating the first mixed solution obtained in S4 for 4 h, then reacting in an oven at a temperature of 80 ℃ for 8 h to obtain a second product; S6, the second product is heated to 800 DEG C at a temperature increasing rate of 5 DEG C / min from room temperature in a nitrogen atmosphere, and then is calcined at 800 DEG C in a nitrogen atmosphere for 3 hours, to obtain a mesoporous carbon composite material in the form of Cu-N3, i.e., a nitrogen-doped hollow mesoporous carbon loaded with metal monatomic atoms (N-HCMS@Cu-SACS).

[0057] Example 2 A method for preparing a mesoporous carbon composite material, comprising the following steps: S1, 0.1 mL of ammonia water is mixed with 30 mL of deionized water, stirred for more than 1 hour, then 0.1 g of 3-aminophenol is added, continuously stirred for 30 minutes, then 0.14 mL of formaldehyde solution is added, stirred at a temperature of 30 DEG C for 30 minutes, to obtain a first product; S2, the first product prepared in S1 is added to a mixed solution of 50 mL of deionized water, 20 mL of anhydrous ethanol and 1 mL of ammonia water, stirred for 5 minutes, then 0.2 g of cetyltrimethylammonium bromide is added, and then 10 mL of ethyl silicate is added dropwise, mixed uniformly and reacted for 10 hours, then 35 mL of N,N-dimethylformamide is added to dissolve the oligomer, the precipitated product is collected by centrifugation, and then the precipitated product is dried at a temperature of 60 DEG C for 8 hours to obtain a solid product; S3, the solid product obtained in S2 is calcined at a temperature of 800 DEG C in a nitrogen (N2) atmosphere for 3 hours to realize carbonization and etching, to obtain a nitrogen-doped hollow mesoporous carbon (i.e., N-HMCS); S4, 0.6 g of copper acetylacetonate is added to 20 mL of anhydrous ethanol, then 0.2 g of nitrogen-doped hollow mesoporous carbon is added, and then 50 mL of acetone is added, stirred uniformly to obtain a first mixed solution; S5, the first mixed solution obtained in S4 is ultrasonically treated for 4 hours, and then is reacted at a constant temperature in an oven at a temperature of 80 DEG C for 8 hours to obtain a second product; S6, the second product is heated to 800 DEG C at a temperature increasing rate of 5 DEG C / min from room temperature in a nitrogen atmosphere, and then is calcined at 800 DEG C in a nitrogen atmosphere for 3 hours, to obtain a mesoporous carbon composite material in the form of Cu-N3, i.e., a nitrogen-doped hollow mesoporous carbon loaded with metal monatomic atoms (N-HCMS@Cu-SACS-1).

[0058] Example 3 A method for preparing a mesoporous carbon composite material, comprising the following steps: S1, 0.1 mL of ammonia water was mixed with 30 mL of deionized water, stirred for more than 1 h, then 0.1 g of 3-amino phenol was added, continuously stirred for 30 min, then 0.14 mL of formaldehyde solution was added, stirred for 30 min at a temperature of 30 ℃, to obtain a first product; S2, to the mixed solution of 50 mL of deionized water, 20 mL of anhydrous ethanol and 1 mL of ammonia water, the first product prepared in S1 was added, stirred for 5 min, then 0.2 g of cetyltrimethylammonium bromide was added, then 10 ml of ethyl silicate was added dropwise, mixed uniformly and reacted for 10 h, then 35 mL of N,N-dimethylformamide was added to dissolve the oligomer, the precipitated product was collected by centrifugation, then the precipitated product was dried at a temperature of 60 ℃ for 8 h to obtain a solid product; S3, the solid product obtained in S2 was calcined at a temperature of 800 ℃ for 3 h under a nitrogen (N2) atmosphere to realize carbonization and etching, to obtain nitrogen-doped hollow mesoporous carbon (N-HMCS); S4, 0.3 g of copper acetylacetonate was added to 20 mL of anhydrous ethanol, then 0.4 g of nitrogen-doped hollow mesoporous carbon was added, then 50 mL of acetone was added, stirred uniformly to obtain a first mixed solution; S5, the first mixed solution obtained in S4 was ultrasonically treated for 4 h, then reacted in an oven at a temperature of 80 ℃ for 8 h to obtain a second product; S6, the second product was heated from room temperature to 800 ℃ at a heating rate of 5 ℃ / min under a nitrogen atmosphere, then calcined at a temperature of 800 ℃ for 3 h under a nitrogen atmosphere to obtain a Cu-N3 form mesoporous carbon composite material, namely a nitrogen-doped hollow mesoporous carbon loaded with metal monatomic atoms (N-HCMS@Cu-SACS-2).

[0059] Example 4 A method for degrading tetracycline (TC) in wastewater by sodium persulfate using nitrogen-doped hollow mesoporous carbon loaded with metal monatomic atoms (N-HCMS@Cu-SACS) as a catalyst, comprising the following steps: The N-HCMS@Cu-SACS prepared in Example 1 was added to 40 mL of wastewater containing tetracycline, wherein the initial concentration of tetracycline in the wastewater was 10 mg / L, the pH value of the wastewater was adjusted to 6 with 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form an N-HCMS@Cu-SACS / PDS system, and the catalytic reaction was started under normal temperature and pressure and in the dark. At 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, 1 mL of the reacted liquid was collected by 0.22 μm polyethersulfone membrane filtration and detected on a high performance liquid chromatograph. The degradation of TC was determined with the original wastewater containing 10 mg / L of tetracycline as a control, and the results are shown in Figure 1 .

[0060] Example 5 The effect of catalyst dosage on the degradation efficiency of TC by N-HCMS@Cu-SACS / PDS was investigated.

[0061] A method for degrading tetracycline (TC) in wastewater by sodium persulfate using metal monatomic atom-loaded nitrogen-doped hollow mesoporous carbon (N-HCMS@Cu-SACS) as a catalyst, comprising the following steps: The N-HCMS@Cu-SACS prepared in Example 1 was added to 40 mL of wastewater containing tetracycline, wherein the initial concentration of tetracycline in the wastewater was 10 mg / L, the pH value of the wastewater was adjusted to 6 with 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form an N-HCMS@Cu-SACS / PDS system, and the catalytic reaction was started under normal temperature and pressure and in the dark. At 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, 1 mL of the reacted liquid was collected by 0.22 μm polyethersulfone membrane filtration and detected on a high performance liquid chromatograph. The degradation of TC was determined with the original wastewater containing 10 mg / L of tetracycline as a control, and the results are shown in Figure 2 .

[0062] Example 6 The effect of TC initial concentration on the degradation efficiency of TC by N-HCMS@Cu-SACS / PDS was investigated.

[0063] A method for degrading tetracycline (TC) in wastewater by sodium persulfate using metal monatomic atom-loaded nitrogen-doped hollow mesoporous carbon (N-HCMS@Cu-SACS) as a catalyst, comprising the following steps: 15 mg of N-HCMS@Cu-SACS prepared in Example 1 was added to 40 mL of wastewater containing tetracycline, wherein the initial concentration of tetracycline in the wastewater was 5 mg / L, 10 mg / L, 20 mg / L, 30 mg / L, and 50 mg / L, respectively, the pH value of the wastewater was adjusted to 6 with 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form N-HCMS@Cu-SACS, sodium persulfate system, and the catalytic reaction was started under normal temperature and pressure and in the dark. At 2 min, 4 min, 6 min, 8 min, 10 min, and 12 min, 1 mL of the reacted liquid was collected by 0.22 μm polyethersulfone membrane filtration and detected on a high performance liquid chromatograph to determine the degradation of TC, and the results are shown in Figure 3 .

[0064] Example 7 The effect of wastewater pH on the degradation efficiency of TC by N-HCMS@Cu-SACS / PDS was investigated.

[0065] A method for degrading tetracycline (TC) in wastewater by N-HCMS@Cu-SACS as catalyst catalyzing sodium persulfate, comprising the following steps: 15 mg of N-HCMS@Cu-SACS prepared in Example 1 was added to 40 mL of wastewater containing tetracycline, wherein the initial concentration of tetracycline in the wastewater was 10 mg / L, the pH value of the wastewater was adjusted to 1, 3, 5, 6, 7, 9, and 11 with 0.1 M NaOH or 0.1 M H2SO4, respectively, the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form N-HCMS@Cu-SACS, sodium persulfate system, and the catalytic reaction was started under normal temperature and pressure and in the dark. At 2 min, 4 min, 6 min, 8 min, 10 min, and 12 min, 1 mL of the reacted liquid was collected by 0.22 μm polyethersulfone membrane filtration and detected on a high performance liquid chromatograph to determine the degradation of TC, and the results are shown in Figure 4 .

[0066] Example 8 The recyclability of the catalyst was evaluated, the reacted catalyst was collected by filtration and washed several times with deionized water and ethanol before use, and the above application example operation was continued to be repeated for 5 times.

[0067] A method for degrading tetracycline (TC) in wastewater by sodium persulfate using nitrogen-doped hollow mesoporous carbon loaded with metal monatomic atoms (N-HCMS@Cu-SACS) as a catalyst, comprising the following steps: 15 mg of N-HCMS@Cu-SACS prepared in Example 1 was added to 40 mL of wastewater containing tetracycline, wherein the initial concentration of tetracycline in the wastewater was 10 mg / L, the pH value of the wastewater was adjusted to 6 using 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form a N-HCMS@Cu-SACS, sodium persulfate system, and the catalytic reaction was started under normal temperature and pressure and in the dark, 1 mL of the reacted liquid was collected by 0.22 μm polyethersulfone membrane filtration at 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, and detected on a high performance liquid chromatograph, and the catalyst after the reaction was filtered and collected and washed several times with deionized water and ethanol before use, and the above operation was repeated, and the degradation of TC was determined, and the results are shown in Figure 5 .

[0068] Example 9 Effect of quenching agent on TC degradation efficiency of N-HCMS@Cu-SACS / PDS A method for degrading tetracycline (TC) in wastewater by sodium persulfate using nitrogen-doped hollow mesoporous carbon loaded with metal monatomic atoms (N-HCMS@Cu-SACS) as a catalyst, comprising the following steps: 15 mg of N-HCMS@Cu-SACS prepared in Example 1 was added to 40 mL of wastewater containing tetracycline, wherein the initial concentration of tetracycline in the wastewater was 10 mg / L, the pH value of the wastewater was adjusted to 6 using 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form a N-HCMS@Cu-SACS, sodium persulfate system, and the catalytic reaction was started under normal temperature and pressure and in the dark, 1 mL of the reacted liquid was collected by 0.22 μm polyethersulfone membrane filtration at 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, and detected on a high performance liquid chromatograph, and the catalyst after the reaction was filtered and collected and washed several times with deionized water and ethanol before use, and the above operation was repeated, and the degradation of TC was determined, and the results are shown in Figure 6 .

[0069] Example 10 To investigate the degradation efficiency of TC in different water matrix The method for degrading tetracycline (TC) in wastewater by sodium persulfate using nitrogen-doped hollow mesoporous carbon loaded with metal single atoms (N-HCMS@Cu-SACS) as a catalyst, comprises the following steps: 15 mg of N-HCMS@Cu-SACS prepared in Example 1 was added into 40 mL of deionized water containing tetracycline, tap water and river water, respectively, wherein the initial concentration of tetracycline in the deionized water, tap water and river water was 10 mg / L, the pH value of the water was adjusted to 6 with 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form a N-HCMS@Cu-SACS, sodium persulfate system, and the catalytic reaction was started under normal temperature and pressure and in the dark, 1 mL of the liquid after reaction was collected by 0.22 μm polyethersulfone membrane filtration at 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, and detected on a high performance liquid chromatograph to determine the degradation of TC, and the results are shown in Figure 7 .

[0070] Example 11 To investigate the degradation efficiency of catalyst on different antibiotics The method for degrading tetracycline (TC), oxytetracycline HCL and sulfamethoxazole (SMX) in wastewater by sodium persulfate using nitrogen-doped hollow mesoporous carbon loaded with metal single atoms (N-HCMS@Cu-SACS) as a catalyst, comprises the following steps: 15 mg of N-HCMS@Cu-SACS prepared in Example 1 was added into 40 mL of wastewater containing tetracycline, oxytetracycline HCL and sulfamethoxazole, respectively, wherein the initial concentration of tetracycline, oxytetracycline HCL and sulfamethoxazole in the wastewater was 10 mg / L, the pH value of the wastewater was adjusted to 6 with 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form a N-HCMS@Cu-SACS, sodium persulfate system, and the catalytic reaction was started under normal temperature and pressure and in the dark, 1 mL of the liquid after reaction was collected by 0.22 μm polyethersulfone membrane filtration at 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, and detected on a high performance liquid chromatograph to determine the degradation of TC, and the results are shown in Figure 8 .

[0071] Comparative Example 1 A method for catalyzing sodium persulfate to degrade tetracycline (TC) in wastewater by using acetylacetone copper as a catalyst comprises the following steps: 15 mg of acetylacetone copper was added to 40 mL of wastewater containing tetracycline, wherein the concentration of tetracycline in the wastewater was 10 mg / L, the pH value of the wastewater was adjusted to 6 by using 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form a Cu-sodium persulfate system, and the catalytic reaction was started under normal temperature and pressure and in the dark, 1 mL of the liquid after the reaction was collected by filtering through a 0.22 μm polyethersulfone membrane at 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, and detected on a high-performance liquid chromatograph to determine the degradation of TC, and the results are shown in Figure 1 .

[0072] Comparative Example 2 A method for catalyzing sodium persulfate to degrade tetracycline (TC) in wastewater by using nitrogen-doped hollow mesoporous carbon (N-HMCS) as a catalyst comprises the following steps: 15 mg of N-HMCS was added to 40 mL of wastewater containing tetracycline, wherein the concentration of tetracycline in the wastewater was 10 mg / L, the pH value of the wastewater was adjusted to 6 by using 0.1 M NaOH or 0.1 M H2SO4, and the reaction was stirred for 30 min to establish adsorption equilibrium, then 10 mg of sodium persulfate was added to form an N-HMCS-sodium persulfate system, and the catalytic reaction was started under normal temperature and pressure and in the dark, 1 mL of the liquid after the reaction was collected by filtering through a 0.22 μm polyethersulfone membrane at 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, and detected on a high-performance liquid chromatograph to determine the degradation of TC, and the results are shown in Figure 1 .

[0073] Comparative Example 3 A method for degrading tetracycline (TC) in wastewater by adding only N-HCMS@Cu-SACS comprises the following steps: 15 mg N-HCMS@Cu-SACS was added into 40 mL sewage containing tetracycline, wherein the concentration of tetracycline in the sewage was 10 mg / L, the pH value of the sewage was adjusted to 6 with 0.1 M NaOH or 0.1 M H2SO4, and the adsorption equilibrium was established by stirring for 30 min to form an N-HCMS@Cu-SACS system. The catalytic reaction was started under normal temperature and pressure and in the dark. At 2 min, 4 min, 6 min, 8 min, 10 min and 12 min, 1 mL of the reacted liquid was collected by filtration through a 0.22 μm polyether sulfone membrane and detected on a high performance liquid chromatograph to determine the degradation of TC, and the results are shown in Figure 1 .

[0074] Detection analysis 1) Characterization of N-HCMS and N-HCMS@Cu-SAC The morphology, physical and chemical properties and catalytic activity of N-HCMS prepared in S3 and N-HCMS@Cu-SAC prepared in S6 of Example 1 were analyzed, detected and characterized. The morphology of the catalyst was observed by scanning electron microscopy SEM. The phase of the catalyst was studied by X-ray diffraction XRD. The dispersion of copper single atoms was determined by spherical aberration electron microscopy-high angle annular dark field-scanning transmission electron microscopy HAADF-STEM. The results are shown in Figures 9 to 11 .

[0075] Figure 9 The SEM images of N-HCMS obtained in S3 and N-HCMS@Cu-SAC obtained in S6 of Example 1 are shown in Figure 9 It can be seen that N-HCMS has a hollow spherical structure, a large specific surface area and a uniform pore size distribution. The specific surface area of the composite material is 1140-1255 m 2 g -1 ; N-HCMS@Cu-SAC is distributed in the form of particles.

[0076] Figure 10 The XRD pattern of N-HCMS@Cu-SAC obtained in S6 of Example 1 is shown in Figure 10 It can be seen that the (002) crystal plane diffraction characteristic peak of graphite phase carbon nitride appears at 27.5°; no specific peak of Cu nanoparticles is observed, which proves that the anchored Cu has been converted into Cu single atoms in the mesoporous carbon.

[0077] Figure 11 The HAADF-STEM image of N-HCMS@Cu-SAC obtained in S6 of Example 1 is shown in Figure 11 It can be seen that Cu is distributed in the form of single atoms on N-HCMS, and the size of single Cu atom is 0.26 nm.

[0078] Degradation analysis of antibiotics in wastewater Figure 1 In this context, N-HCMS@Cu-SACS, PDS corresponds to the degradation system in Example 4; N-HMCS, PDS corresponds to the degradation system in Control Example 2; Cu, PDS corresponds to the degradation system in Control Example 1; N-HCMS@Cu-SACS corresponds to the degradation system in Control Example 3; and Blank corresponds to the wastewater containing 10 mg / L tetracycline. Figure 1 The results show that the N-HCMS@Cu-SACS / PDS system achieved a 100% degradation rate of TC after 4 minutes. The Cu / PDS system achieved a 24% degradation rate of TC, while the N-HCMS / PDS system achieved a 61% degradation rate. This demonstrates that N-HCMS@Cu-SACS can effectively degrade tetracycline with high efficiency.

[0079] From such Figure 2 and Figure 3 Analysis revealed that the optimal amounts of N-HCMS@Cu-SACS and TC concentrations during the reaction were 15 mg and 10 mg / L, respectively.

[0080] from Figure 4 Analysis showed that within the pH range of 3 to 9, the degradation rate of TC by the N-HCMS@Cu-SACS / PDS system reached 100% with increasing time. When the pH was 1 and 11, the degradation rate of TC decreased slightly to 76.4% and 83.3%, respectively.

[0081] from Figure 5 Analysis showed that the catalyst used after a single recovery had no significant impact on the degradation efficiency of TC. However, when N-HCMS@Cu-SACS was recovered multiple times, the degradation efficiency of TC decreased significantly. This may be related to the byproducts remaining on the catalyst surface.

[0082] from Figure 6 Analysis shows that N-HCMS@Cu-SACS can activate PDS to produce ·OH and SO4. - ·, O2ˉ·, and 1 O2 and other active oxygen species remove tetracycline from water. 1 O2 contributes significantly. Figure 12 EPR testing detected ·OH, SO4. - ·, O2ˉ·, and 1 The O2 signal also confirms this conclusion.

[0083] from Figure 7From the analysis in Table 4, in the water matrix of deionized water, tap water and river water, the removal rates of TC are 100%, 94.3% and 81.6% respectively in 12 min. The N-HCMS@Cu-SACS / PDS system has good removal effect on TC and fast reaction rate.

[0084] From the analysis in Table 4, in the water matrix of deionized water, tap water and river water, the removal rates of TC are 100%, 94.3% and 81.6% respectively in 12 min. The N-HCMS@Cu-SACS / PDS system has good removal effect on TC and fast reaction rate. Figure 8 From the analysis in Table 4, in the water matrix of deionized water, tap water and river water, the removal rates of TC are 100%, 94.3% and 81.6% respectively in 12 min. The N-HCMS@Cu-SACS / PDS system has good removal effect on TC and fast reaction rate.

[0085] The above examples are only preferred examples for fully illustrating the present application, and the protection scope of the present application is not limited thereto. Any equivalent replacement or transformation made by the person skilled in the art based on the present application is within the protection scope of the present application.

Claims

1. A mesoporous carbon composite material, characterized in that, It includes nitrogen-doped hollow mesoporous carbon and metal single atoms supported on the nitrogen-doped hollow mesoporous carbon.

2. The mesoporous carbon composite material according to claim 1, characterized in that, The metal single atom is a copper single atom.

3. The method for preparing the mesoporous carbon composite material according to claim 1 or claim 2, characterized in that, Includes the following steps: S1. Add 3-aminophenol and formaldehyde to alkaline water, react, and obtain the first product; S2. Add the first product to the mixed solution of organic solvent and alkali, then add hexadecyltrimethylammonium bromide and ethyl silicate in sequence, mix well, then add N,N-dimethylformamide, centrifuge, and dry to obtain a solid product; S3. The solid product is calcined in a nitrogen atmosphere to obtain nitrogen-doped hollow mesoporous carbon. S4. Add the mixed solution of copper acetylacetone and organic solvent, and the nitrogen-doped hollow mesoporous carbon to the acetone solution to obtain the first mixed solution; S5. The first mixed solution is sonicated and then heated to react, yielding the second product; S6. The second product is heated to a preset temperature in a nitrogen atmosphere and calcined at a constant temperature to obtain a mesoporous carbon composite material, namely nitrogen-doped hollow mesoporous carbon loaded with metal single atoms.

4. The method for preparing mesoporous carbon composite material according to claim 3, characterized in that, The alkali is selected from ammonia water; And / or, the organic solvent is selected from anhydrous ethanol; And / or, in the alkaline water, the volume ratio of alkali to water is 0.1~0.3:20~30; And / or, the 3-aminophenol, the formaldehyde, the hexadecyltrimethylammonium bromide, the ethyl silicate, and the N,N-dimethylformamide are expressed in a ratio of 0.1~0.3 g:0.1~0.15 mL:0.1~0.3 g:5~10 mL:30~50 mL in g:mL:g:mL:mL; And / or, the volume ratio of organic solvent to base in the mixed solution of organic solvent and base is 20~30:0.5~1.5; And / or, the mass ratio of the copper acetylacetonate to the nitrogen-doped hollow mesoporous carbon is 0.15~0.6:0.1~0.

4.

5. The method for preparing mesoporous carbon composite material according to claim 3, characterized in that, The calcination in a nitrogen atmosphere is at a temperature of 550~800 ℃ for 2~5 h. And / or, the preset temperature is 600~800 ℃, the constant temperature calcination time is 3~6 h, the heating method in the nitrogen atmosphere is programmed heating, and the heating rate of the programmed heating is 5 ℃ / min; And / or, the ultrasound duration is 4 h, the heating reaction temperature is 60~80 ℃, and the duration is 6~8 h.

6. The use of the mesoporous carbon composite material prepared by the preparation method according to any one of claims 3 to 5 as a catalyst.

7. The application according to claim 6, characterized in that, The mesoporous carbon composite material is used as a catalyst for the catalytic degradation of antibiotics in wastewater.

8. The application according to claim 7, characterized in that, The mesoporous carbon composite material is used as a catalyst to catalyze the degradation of antibiotics in wastewater by persulfate.

9. The application according to claim 8, characterized in that, The persulfate is selected from sodium persulfate; And / or, the antibiotics include at least one of tetracycline, oxytetracycline hydrochloride, and sulfamethoxazole; And / or, the mass ratio of the persulfate to the mesoporous carbon composite material is 1:0.5~1.5; And / or, when the mass ratio of antibiotics, persulfate (PDS) and mesoporous carbon composite material in wastewater is 0.04~0.2:1:0.5~1.5, the time to reduce the antibiotics in wastewater to 0 is 12~20 min.

10. The application according to claim 8, characterized in that, The method for using the mesoporous carbon composite material as a catalyst to catalyze the degradation of antibiotics in wastewater by persulfate includes the following steps: The composite material of persulfate and mesoporous carbon was added to wastewater containing antibiotics, mixed evenly, and then reacted under normal temperature, normal pressure, and light-protected conditions to remove antibiotics from the wastewater.

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