Co / C / Al2O3 composite material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of antibiotic resistance gene wastewater treatment, and discloses a Co / C / Al2O3 composite material as well as a preparation method and application thereof. The method comprises the following steps: (1) respectively dissolving Al (NO3) 39H2O and terephthalic acid in water; (2) transferring the solution into a reaction kettle and heating; (3) after the reaction kettle is cooled, centrifugally separating to obtain a precipitate, washing with ethanol and water, and drying the obtained solid until the mass is unchanged; (4) weighing Al-MIL-53 and Co (NO3) 36H2O, putting the weighed Al-MIL-53 and Co (NO3) 36H2O into DMF (5) after the reaction kettle is cooled, centrifugally separating to obtain a precipitate, and washing with methanol and ethanol; (6) putting the Co / Al-MIL-53 powder into a crucible, and heating the Co / Al-MIL-53 powder; the material obtained by the method can be used for treating wastewater containing antibiotic resistance genes, and can effectively degrade the antibiotic resistance genes.

Description

Technical Field

[0001] The present invention relates to the technical field of antibiotic resistance gene wastewater treatment, and particularly relates to a Co / C / Al2O3 composite material, a preparation method thereof, and an application thereof. Background Art

[0002] As an emerging pollutant, antibiotic resistance genes (ARGs) have been widely detected in surface water and groundwater. Antibiotic resistance genes (ARGs) have been regarded as one of the global health challenges. The existence of ARGs may affect the ecological environment and lead the world into the post-antibiotic era. The continuous migration of ARGs in the environment poses a serious threat to human health. Compared with biological treatment processes, advanced oxidation processes exhibit excellent performance in removing ARGs and can effectively degrade ARGs. Persulfate can be activated by means of light, heat, metal ions, etc. to achieve rapid and efficient oxidation of pollutants.

[0003] Al-MIL-53 is a metal-organic framework (MOFs) material. MOFs materials have a large specific surface area, porosity, and adjustable pore structures. Al-MIL-53 materials are used for the adsorption of inorganic and organic pollutants.

[0004] Co is a transition metal. Compared with elements such as Fe, Cu, and Ni, Co has a high activation efficiency for PMS. In an aqueous solution, Co can rapidly decompose persulfate and generate strongly oxidizing free radicals and non-free radicals. The strongly oxidizing groups can attack the base structure of antibiotic resistance genes to achieve the destruction of the structure and function of antibiotic resistance genes, thereby completely degrading antibiotic resistance genes.

[0005] By pyrolyzing Al-MIL-53, a C / Al2O3 material is obtained, and then metal cobalt is loaded onto C / Al2O3 by a solvothermal method. The porous properties and DNA binding sites of C / Al2O3 can be utilized to first adsorb ARGs, and then the ability of metal cobalt to activate persulfate to generate free radicals and non-free radicals can be used to improve the removal effect of ARGs.

[0006] Therefore, how to combine the ability of metal cobalt to activate persulfate with the ability of Al-MOF to adsorb ARGs to construct a composite material for adsorbing and degrading antibiotic resistance genes is a technical problem worthy of research. Summary of the Invention

[0007] The object of the present invention is: based on the above technical problems, to solve the problem of poor removal effect of antibiotic resistance genes by using Al-MIL-53 materials.

[0008] To achieve the above object, the first aspect of the present invention provides a preparation method of a Co / C / Al2O3 composite material, and the method includes the following steps: (1) Weigh Al(NO3)3•9H2O and terephthalic acid, add them to water, dissolve by ultrasonic treatment, then transfer to a polytetrafluoroethylene inner liner and place in a reaction kettle. Heat at 168 - 172 °C for 24 - 24.5 h. Let the reaction kettle cool naturally to room temperature, centrifuge at 8000 - 10000 rpm for 5 min, take the precipitate, wash it 3 times with ethanol and water respectively, take the precipitate, and then dry it at 68 - 72 °C until the mass remains unchanged to obtain Al-MIL-53; (2) Weigh the obtained Al-MIL-53 and Co(NO3)3•6H2O, add them to 50 mL of DMF, dissolve by ultrasonic treatment, then transfer to a 100 mL polytetrafluoroethylene inner liner and place in a reaction kettle. Heat at 168 - 172 °C for 6 - 6.5 h. Wait for the reaction kettle to cool naturally to room temperature, centrifuge at 8000 - 10000 rpm for 5 min, take the precipitate, wash it 3 times with methanol and ethanol respectively, and take the precipitate; (3) Heat the above precipitate in an oven at 60 - 65 °C for 12 - 12.5 h to obtain Co / Al-MIL-53 powder. Place the powder in a crucible and heat it at 600 °C for 4 h to obtain Co / C / Al2O3 composite material.

[0009] The second aspect of the present invention provides a Co / C / Al2O3 composite material prepared by the method described in the first aspect of the present invention.

[0010] The third aspect of the present invention provides the application of the Co / C / Al2O3 composite material described in the second aspect of the present invention in treating sewage containing antibiotic resistance genes.

[0011] The Co / C / Al2O3 composite material provided by the present invention, its preparation method and application have at least the following beneficial effects: (1) The method provided by the present invention synthesizes a Co / C / Al2O3 composite material by loading Co onto C / Al2O3. The material preparation is simple and the cost is low. The material is used in the treatment of antibiotic resistance genes to achieve the purpose of efficiently treating antibiotic resistance genes.

[0012] (2) The preparation of Co / C / Al2O3 in the present invention is simple in operation and can be prepared by hydrothermal synthesis and pyrolysis.

[0013] (3) The Co / C / Al2O3 prepared by the present invention has a very obvious effect on the degradation of the antibiotic resistance gene tetW. For a tetW solution with an initial concentration of ~10 10 copies / mL, add Co / C / Al2O 3、After 20 min of potassium peroxymonosulfate (PMS), the removal efficiency of tetW was 5.85 log. Under the same conditions, the removal efficiencies of tetW by Al-MIL-53 and C / Al2O3 were 3.24 log and 3.29 log, respectively.

[0014] Other features and advantages of the present invention will be described in detail in the following specific implementation section. Brief Description of the Drawings

[0015] Figure 1 It is a comparative diagram of the degradation effects of Co0.01 / C / Al2O3-600 obtained in Example 1 of the present invention, Co0.02 / C / Al2O3-600 obtained in Example 2, Al-MIL-53 obtained in Comparative Example 1, and C / Al2O3 obtained in Comparative Example 2 on tetW;

[0016] Figure 2 It is a comparative diagram of the degradation effects of Co0.01 / C / Al2O3-600 obtained in Example 1, Co / C / Al2O3-750 obtained in Comparative Example 3, and Co / C / Al2O3-900 obtained in Comparative Example 4 on tetW. Detailed Description of the Invention

[0017] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range and a single point value, and between single point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0018] In the present invention, on the one hand, C / Al2O3 has a porous structure, and Al can combine with the phosphate ester bonds in the gene DNA structure. First, it can achieve efficient adsorption of antibiotic resistance gene pollutants, and then activate persulfate through the loaded metal cobalt to generate free radicals and non-free radicals. The strong oxidation ability of free radicals and non-free radicals is used to destroy the base structure of antibiotic resistance genes, thereby degrading antibiotic resistance genes.

[0019] As described above, the first aspect of the present invention provides a method for preparing a Co / C / Al2O3 composite material, and the method includes the following steps: (1) Weigh Al(NO3)3•9H2O and terephthalic acid, add them to water, dissolve by ultrasonic treatment, then transfer to a polytetrafluoroethylene inner liner and place in a reaction kettle. Heat at 168 - 172 °C for 24 - 24.5 h. Let the reaction kettle cool naturally to room temperature, centrifuge at 8000 - 10000 rpm for 5 min, collect the precipitate, wash it three times with ethanol and water respectively, collect the precipitate, and then dry it at 68 - 72 °C until the mass remains unchanged to obtain Al-MIL-53; (2) Weigh the obtained Al-MIL-53 and Co(NO3)3•6H2O, add them to 50 mL of DMF, dissolve by ultrasonic treatment, then transfer to a 100 mL polytetrafluoroethylene inner liner and place in a reaction kettle. Heat at 168 - 172 °C for 6 - 6.5 h. Wait for the reaction kettle to cool naturally to room temperature, centrifuge at 8000 - 10000 rpm for 5 min, collect the precipitate, wash it three times with methanol and ethanol respectively, and collect the precipitate; (3) Heat the above precipitate in an oven at 60 - 65 °C for 12 - 12.5 h to obtain Co / Al-MIL-53 powder. Place the powder in a crucible and heat it at 600 °C for 4 h to obtain Co / C / Al2O3 composite material.

[0020] Preferably, in step (1), the molar ratio of the amounts of Al(NO3)3•9H2O and terephthalic acid used is 1:1.

[0021] More preferably, in step (1), the amount of water used is 60 - 62 mL.

[0022] Preferably, in step (2), the amount of Co(NO3)3•6H2O used is 10 - 20 mg.

[0023] More preferably, in step (2), the amount of Al-MIL-53 used is 30 - 35 mg.

[0024] Preferably, in step (2), the amount of DMF used is 50 - 52 mL.

[0025] As described above, the second aspect of the present invention provides the Co / C / Al2O3 composite material prepared by the method described in the first aspect of the present invention.

[0026] As described above, the third aspect of the present invention provides the application of the Co / C / Al2O3 composite material described in the second aspect of the present invention in treating sewage containing antibiotic resistance genes.

[0027] The present invention will be described in detail below through examples. In the following examples, unless otherwise specified, the raw materials are all commercially available products.

[0028] Example 1

[0029] This example provides a method for preparing Co / C / Al2O3-600 composite material, which includes the following steps: (1) Weigh 5.6269 g of Al(NO3)3•9H2O and 2.4919 g of terephthalic acid, add them to 60 mL of water, dissolve them by ultrasonic wave, then transfer them to a 100 mL polytetrafluoroethylene inner liner, and place it in a reaction kettle. Heat it at 170 °C for 24 h. Wait for the kettle to cool naturally to room temperature, centrifuge at 8000 rpm for 5 min, take the precipitate, and wash it 3 times with ethanol and water respectively. Take the precipitate, and then place it in an oven at 68 °C and dry it until the mass remains unchanged to obtain Al-MIL-53.

[0030] (2) Weigh 30 mg of the above-mentioned Al-MIL-53 and 10 mg of Co(NO3)3•6H2O, add them to 50 mL of DMF, dissolve them by ultrasonic wave, then transfer them to a 100 mL polytetrafluoroethylene inner liner, and place it in a reaction kettle. Heat it at 170 °C for 6 h. Wait for the kettle to cool naturally to room temperature, centrifuge at 8000 rpm for 5 min, take the precipitate, and wash it 3 times with methanol and ethanol respectively. Take the precipitate.

[0031] (3) Place the above precipitate in an oven and heat it at 60 °C for 12 h to obtain Co / Al-MIL-53 powder. Then place the powder in a crucible and heat it at 600 °C for 4 h to obtain the composite material, denoted as Co / C / Al2O3-600.

[0032] Example 2

[0033] This example is carried out according to the method of Example 1, except that in step (2), the dosage of Co(NO3)3•6H2O is 20 mg, and the other steps and parameters are the same as those in Example 1.

[0034] Comparative Example 1

[0035] This example is carried out according to the method of Example 1, except that steps (2) and (3) are not carried out, and only step (1) is carried out, and the other steps and parameters are the same as those in Example 1.

[0036] Among them, the obtained composite material is denoted as Al-MIL-53.

[0037] Comparative Example 2

[0038] This example is carried out according to the method of Example 1, except that step (2) is not carried out, and the other steps and parameters are the same as those in Example 1.

[0039] Among them, the obtained composite material is denoted as C / Al2O3.

[0040] Comparative Example 3

[0041] This example was carried out according to the method of Example 1. The difference is that in step (3), the powder was placed in a crucible and then heated at 750 °C for 4 h. The remaining steps and parameters were the same as those in Example 1.

[0042] Among them, the obtained composite material was denoted as Co / C / Al2O3-750.

[0043] Comparative Example 4

[0044] This example was carried out according to the method of Example 1. The difference is that in step (3), the powder was placed in a crucible and then heated at 900 °C for 4 h. The remaining steps and parameters were the same as those in Example 1.

[0045] Among them, the obtained composite material was denoted as Co / C / Al2O3-900.

[0046] Test Example 1

[0047] The composite materials prepared in the above Example 1, Example 2 and Comparative Examples 1-2 were tested for the removal effect of antibiotic resistance genes. Specifically, for an antibiotic resistance gene solution with a concentration of ~10 10 copies / mL, the removal efficiencies of Al-MIL-53, C / Al2O3, Co0.01 / C / Al2O3-600, and Co0.02 / C / Al2O3-600 for tetW were 3.24 log, 3.59 log, 5.85 log, and 5.86 log, respectively. It can be seen that Co0.01 / C / Al2O3-600 is the material prepared with the best synthesis ratio.

[0048] Test Example 2

[0049] The composite materials prepared in the above Example 1, Comparative Examples 1-4, and PMS were used to degrade and remove the antibiotic resistance genes in the aqueous solution. The results are as Figure 1 and Figure 2 shown, where Figure 1 is a comparative diagram of the degradation effects of Co0.01 / C / Al2O3-600 obtained in Example 1, Co0.02 / C / Al2O3-600 obtained in Example 2, Al-MIL-53 obtained in Comparative Example 1, and C / Al2O3 obtained in Comparative Example 2 on tetW, Figure 2 is a comparative diagram of the degradation effects of Co0.01 / C / Al2O3-600 obtained in Example 1, Co / C / Al2O3-750 obtained in Comparative Example 3, and Co / C / Al2O3-900 obtained in Comparative Example 4 on tetW.

[0050] Among them, the specific method for degrading and removing the antibiotic resistance genes in the aqueous solution includes:

[0051] Prepare 6 portions of antibiotic resistance gene solutions with a concentration of ~10 10 copies / mL respectively. Take 5 mL of each of the antibiotic resistance gene solutions and place them in 15 mL sterile centrifuge tubes, which are respectively labeled as sterile centrifuge tube I, sterile centrifuge tube II, sterile centrifuge tube III, sterile centrifuge tube IV, sterile centrifuge tube V, and sterile centrifuge tube VI. Then add 1.5 mg of Co0.01 / C / Al2O3-600 obtained in Example 1, Co0.02 / C / Al2O3-600 obtained in Example 2, Al-MIL-53 obtained in Comparative Example 1, C / Al2O3 obtained in Comparative Example 2, Co / C / Al2O3-750 obtained in Comparative Example 3, and Co / C / Al2O3-900 obtained in Comparative Example 4. Then place them in an oscillator and stir at 25 °C and a rotation speed of 400 rpm. Add 0.3 mmol / L PMS respectively. At the 2nd minute, 5th minute, 10th minute, 15th minute, and 20th minute, take 200 μL into sterile centrifuge tubes respectively, add Na2S2O3 quencher, and use real-time fluorescence quantitative PCR to measure the concentration of the antibiotic resistance gene.

[0052] From Figure 1 and Figure 2 it can be seen that Co / C / Al2O3-600 obtained in Example 1 of the present invention has very excellent degradation performance for the tetW antibiotic resistance gene.

[0053] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A preparation method of a Co / C / Al2O3 composite material, characterized in that, The method comprises the following steps: (1) Weigh Al(NO3)3•9H2O and terephthalic acid, add them into water, dissolve by ultrasonic, then transfer to a polytetrafluoroethylene liner, and place it in a reaction kettle. Heat at 168 - 172 °C for 24 - 24.5 h. Let the reaction kettle cool naturally to room temperature, centrifuge at 8000 - 10000 rpm for 5 min, take the precipitate, wash it with ethanol and water three times respectively, take the precipitate, and then dry it at 68 - 72 °C until the mass remains unchanged to obtain Al-MIL-53; (2) Weigh the obtained Al-MIL-53 and Co(NO3)3•6H2O, add them into 50 mL of DMF, dissolve by ultrasonic, then transfer to a 100 mL polytetrafluoroethylene liner, and place it in a reaction kettle. Heat at 168 - 172 °C for 6 - 6.5 h. Wait for the reaction kettle to cool naturally to room temperature, centrifuge at 8000 - 10000 rpm for 5 min, take the precipitate, and wash it with methanol and ethanol three times respectively, take the precipitate; (3) Heat the above precipitate in an oven at 60 - 65 °C for 12 - 12.5 h to obtain Co / Al-MIL-53 powder, place the powder in a crucible, and then heat it at 600 °C for 4 h to obtain Co / C / Al2O3 composite material.

2. The method according to claim 1, wherein In step (1), the molar ratio of the amounts of Al(NO3)3•9H2O and terephthalic acid used is 1:

1.

3. The method according to claim 1 or 2, characterized in that, In step (1), the amount of water used is 60 - 62 mL.

4. The method according to claim 1 or 2, characterized in that, In step (2), the amount of Co(NO3)3•6H2O used is 10 - 20 mg.

5. The method according to claim 1 or 2, characterized in that, In step (2), the amount of Al-MIL-53 used is 30 - 35 mg.

6. The method according to claim 1 or 2, characterized in that, In step (2), the amount of DMF used is 50 - 52 mL.

7. The Co / C / Al2O3 composite material prepared by the method according to any one of claims 1 - 6.

8. The application of the Co / C / Al2O3 composite material according to claim 7 in treating sewage containing antibiotic resistance genes.

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