An electrode material and a capacitive deionization device, and a preparation method and application thereof

Abstract

This invention discloses an electrode material and a capacitive deionization device, as well as their preparation method and application, belonging to the field of water treatment technology. The preparation method of the electrode material includes the following steps: (1) dissolving iron salt and nickel salt in a mixed solvent to prepare a mixed solution; the mixed solvent is composed of N,N-dimethylformamide, anhydrous ethanol and deionized water; (2) adding activated carbon powder, polyvinylpyrrolidone and terephthalic acid to the mixed solution, and then reacting at 125-150℃ for 12-15h; (3) separating the precipitate and washing it, then soaking the precipitate in methanol, drying it and grinding it to obtain the final product. The capacitive deionization device includes an anode made of iron-nickel bimetallic organic framework composite carbon electrode material and a cathode made of activated carbon material. It can be used to remove extracellular antibiotic resistance genes in water, and has the advantages of simple device, low energy consumption and high antibiotic resistance gene removal efficiency.

Description

Technical Field

[0001] This invention belongs to the field of water treatment technology, specifically relating to an electrode material and a capacitor deionization device, as well as their preparation method and application. Background Technology

[0002] Capacitive deionization (CDI) is a novel saline desalination technology that offers numerous advantages over traditional methods, including low energy consumption, environmental friendliness, low cost, easy electrode regeneration, and no secondary pollution. The technology works by applying a small voltage (<1.8 V) between two parallel plates, creating an electrostatic field. When charged ions in the solution flow through the electrodes, they migrate towards the electrodes under the influence of the electric field and are adsorbed onto the electrode material surface, forming a bilayer. This removes the charged ions. When the adsorbed ions approach saturation, short-circuiting or reversing the connection of the two electrodes releases the ions back into the solution, achieving ion desorption.

[0003] Electrode materials are a key factor affecting the performance of capacitive deionization. Metal-organic frameworks (MOFs) are porous network framework materials formed by the self-assembly of metal center ions and multidentate organic ligands. Due to their high specific surface area, tunable pore size, abundant metal active sites and good chemical stability, they have shown great application potential in the field of capacitive deionization.

[0004] The overuse of antibiotics has led to the emergence and spread of antibiotic resistance genes in the aquatic environment. These genes can be detected in various water bodies such as rivers and reservoirs. Extracellular antibiotic resistance genes (eARGs) can persist in environmental media for a long time, are difficult to degrade, and maintain their sequence integrity and transformation ability. They can be transferred into other organisms through horizontal gene transfer, which can easily lead to antibiotic resistance in clinical practice. This can cause antibiotics to become ineffective in disease prevention and control, and even lead to the emergence of "superbugs," posing a serious threat to the ecological environment and public health and safety.

[0005] Tetracycline antibiotics are a class of broad-spectrum antibiotics produced by Streptomyces or synthesized semi-synthetically. They inhibit bacterial protein synthesis and are used to treat infections caused by various Gram-positive and Gram-negative bacteria, finding widespread application in medicine and agriculture. Chloramphenicol is another broad-spectrum antibiotic widely used in human medicine, aquaculture, and animal husbandry. Sulfonamides are also widely used broad-spectrum antibacterial antibiotics, acting by blocking folic acid synthesis and widely applied in veterinary medicine and animal husbandry. Due to the widespread use of antibiotics, their resistance genes spread rapidly among microorganisms through horizontal gene transfer. This not only reduces the effectiveness of antibiotics but may also lead to new infectious diseases. Furthermore, antibiotic residues in soil and water environments also promote the production and spread of resistance genes. Currently, tetracycline antibiotic resistance genes (Tetracycline antibiotic resistance genes) are being studied. tetL ), chloramphenicol antibiotic resistance genes, chL ) and sulfonamide antibiotic resistance genes sulA These resistance genes are already widespread in aquatic environments; they may enter the human body through the food chain, affecting food safety and human health, and have become a serious global public health problem.

[0006] Existing technologies include using ultraviolet light and peracetic acid to remove antibiotics and resistance genes from wastewater, but the addition of peracetic acid as a disinfectant can easily produce disinfection byproducts; microwave radiation technology is used to remove antibiotic resistance genes from water, but it requires specialized microwave radiation devices, which are costly and energy-intensive. Summary of the Invention

[0007] In view of the above-mentioned prior art, the present invention provides an electrode material and a capacitor deionization device, as well as their preparation method and application, to solve the problems of high energy consumption, low efficiency and easy generation of disinfection byproducts in the removal of antibiotic resistance genes in water in the prior art.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a method for preparing an electrode material, comprising the following steps: (1) Dissolve iron salt and nickel salt in a mixed solvent to prepare a mixed solution; the ratio of iron salt, nickel salt and mixed solvent is 1-2.5 mmol: 5-7 mmol: 68-80 mL, and the mixed solvent is composed of N,N-dimethylformamide, anhydrous ethanol and deionized water; (2) Add activated carbon powder, polyvinylpyrrolidone and terephthalic acid to the mixed solution, and then react at 125~150℃ for 12~15 h; the ratio of activated carbon powder, polyvinylpyrrolidone and terephthalic acid is 3-8 g: 0.05-0.2 g: 8-16 mmol; (3) Separate the precipitate from the product after step (2) and wash it. Then soak the precipitate in methanol, dry it and grind it to obtain the final product.

[0009] Based on the above technical solution, the present invention can be further improved as follows.

[0010] Furthermore, the iron salt is ferric chloride, and the nickel salt is nickel dichloride.

[0011] Furthermore, the volume ratio of N,N-dimethylformamide, anhydrous ethanol, and deionized water in the mixed solvent is 60-70:4-5:4-5.

[0012] Furthermore, the proportions of each raw material are as follows: 66 mL of N,N-dimethylformamide, 4.5 mL of anhydrous ethanol, 4.5 mL of deionized water, 1.76 mmol of ferric chloride hexahydrate, 6 mmol of nickel dichloride hexahydrate, 4 g of activated carbon powder, 0.1 g of polyvinylpyrrolidone, and 8 mmol of terephthalic acid.

[0013] Furthermore, the iron-nickel bimetallic organic framework composite carbon electrode material prepared by the above-mentioned electrode material preparation method.

[0014] Furthermore, a capacitor deionization device includes an anode made of the aforementioned iron-nickel bimetallic organic framework composite carbon electrode material and a cathode made of activated carbon material.

[0015] Furthermore, the anode preparation steps are as follows: (1) Mix the iron-nickel bimetallic organic framework composite carbon electrode material, acetylene black and polyvinylidene fluoride in a mass ratio of 8:1:1, then add N-methylpyrrolidone solution to the mixture and stir until uniform to obtain electrode slurry. (2) The electrode paste is evenly coated on the titanium plate and dried.

[0016] Furthermore, the above-mentioned capacitor deionization device is used in the removal of antibiotic resistance genes from water.

[0017] Furthermore, the antibiotic resistance gene is a sulfonamide antibiotic resistance gene, a chloramphenicol antibiotic resistance gene, or a tetracycline antibiotic resistance gene.

[0018] Furthermore, during the removal of antibiotic resistance genes, a DC voltage of 1.5 V is applied to the two electrodes of the capacitor deionization device.

[0019] The beneficial effects of this invention are as follows: The iron-nickel bimetallic organic framework composite carbon electrode material and the capacitive deionization device prepared based on this electrode material provided by this invention can effectively control extracellular antibiotic resistance genes in water. The ion capture and storage capacity of the electrode material is a key factor determining the performance of CDI. Compared with monometallic MOFs, bimetallic MOFs contain two metal active sites. By introducing a second metal ion, defects are generated in the MOF structure, increasing the coordination unsaturation of the MOFs, which is beneficial to improving porosity and increasing more adsorption sites. In addition, combining bimetallic MOFs with traditional activated carbon materials can significantly improve the conductivity and stability of the electrode through synergistic effects, further optimizing the performance of capacitive deionization. This invention directly combines MOF materials with activated carbon materials to prepare MOF / AC composite materials, simplifying the operation steps, eliminating the need for high-temperature treatment, making the operation safer, and effectively shortening the preparation time. Using the iron-nickel bimetallic organic framework composite carbon electrode material prepared by this invention as the anode material of the capacitive deionization device and activated carbon as the cathode material, an asymmetric capacitive deionization device is formed. Experimental results show that this device effectively controls sulfonamide antibiotic resistance genes. sulA The removal efficiency reached 95.93%, and the resistance gene to chloramphenicol antibiotics was eliminated. chL The removal efficiency reached 99.15%, and it was effective against tetracycline antibiotic resistance genes. tetL The removal efficiency reached 94.52%, which can effectively control extracellular antibiotic resistance genes in water. It has the advantages of simple device, low energy consumption and high antibiotic resistance gene removal efficiency. Attached Figure Description

[0020] Figure 1 SEM image of the iron-nickel bimetallic organic framework composite carbon electrode material; Figure 2 Elemental distribution diagram of iron-nickel bimetallic organic framework composite carbon electrode material; Figure 3 Here is a simplified diagram of the CDI module structure; where 1, first glass end plate, 2, first silicone gasket, 3, first current collector, 4, cation exchange membrane, 5, second silicone gasket, 6, plastic partition, 7, third silicone gasket, 8, anion exchange membrane, 9, second current collector, 10, fourth silicone gasket, 11, second glass end plate, 12, water inlet, 13, water outlet, 14, first tab, 15, second tab, 16, electrode material; Figure 4 Extracellular antibiotic resistance gene sulA Changes in gene abundance over treatment time; Figure 5 For different times sulA The removal rate of resistance genes; Figure 6 Extracellular antibiotic resistance gene chL Changes in gene abundance over treatment time; Figure 7 For different times chL The removal rate of resistance genes; Figure 8 Extracellular antibiotic resistance gene tetL Changes in gene abundance over treatment time; Figure 9 For different times tetL The removal rate of resistance genes. Detailed Implementation

[0021] The specific embodiments of the present invention will be described in detail below with reference to examples.

[0022] Example 1 A method for preparing an iron-nickel bimetallic organic framework composite carbon electrode material (FeNi-MOF / AC) specifically includes the following steps: (1) Weigh 1.4256 g (6 mmol) nickel dichloride hexahydrate and 0.4752 g (1.76 mmol) ferric chloride hexahydrate into a beaker, then add 66 mL N,N-dimethylformamide, 4.5 mL deionized water and 4.5 mL anhydrous ethanol into the beaker and stir until homogeneous. Then sonicate to ensure complete dissolution and prepare a mixed solution. (2) Add 4 g of pre-treated activated carbon powder and 0.1 g of polyvinylpyrrolidone dispersant to the mixed solution, and sonicate to form a homogeneous solution; then add 1.329 g (8 mmol) of terephthalic acid, and continue to sonicate to form a homogeneous mixed solution; transfer the mixed solution to a 200 mL polytetrafluoroethylene-lined high-temperature and high-pressure reactor, and react at 125 °C for 15 h with a stirring rate of 200 rpm. The pretreatment steps of activated carbon are as follows: Place activated carbon powder in deionized water, heat to 60 ℃ and stir for 2 h, then filter it, wash it repeatedly with deionized water and ethanol 3 times, dry it in a forced-air oven at 60 ℃ for 12 h, grind it and set it aside. (3) After the reaction is completed, the supernatant is separated by centrifugation, the precipitate is collected, and the precipitate is washed three times by centrifugation with N,N-dimethylformamide and anhydrous ethanol. The precipitate is then soaked in methanol solution for 24 h, and the methanol is replaced every 12 h. Finally, it is dried in a forced-air drying oven at 60 ℃ for 12 h. After it is naturally cooled to room temperature, it is taken out, ground and passed through a 200-mesh sieve to obtain the iron-nickel bimetallic organic framework composite carbon electrode material.

[0023] SEM image of the iron-nickel bimetallic organic framework composite carbon electrode material is shown below. Figure 1 As shown, the microstructure of the prepared iron-nickel bimetallic organic framework is a cluster structure composed of nanosheets combined with activated carbon.

[0024] The elemental distribution diagram of the iron-nickel bimetallic organic framework composite carbon electrode material is as follows: Figure 2 As shown, Fe and Ni elements are uniformly distributed in the material, further indicating that the iron-nickel bimetallic organic framework was successfully synthesized.

[0025] Example 2 A method for preparing an iron-nickel bimetallic organic framework composite carbon electrode material (FeNi-MOF / AC) specifically includes the following steps: (1) Weigh 2.1384 g (9 mmol) nickel dichloride hexahydrate and 0.7128 g (2.64 mmol) ferric chloride hexahydrate into a beaker, then add 99 mL N,N-dimethylformamide, 6.8 mL deionized water and 6.8 mL anhydrous ethanol into the beaker and stir until homogeneous. Then sonicate to ensure complete dissolution and prepare a mixed solvent. (2) Add 4 g of pre-treated activated carbon powder and 0.1 g of polyvinylpyrrolidone dispersant to the mixed solvent, and sonicate to form a homogeneous solution; then add 1.9935 g (12 mmol) of terephthalic acid, and continue sonication to form a homogeneous mixed solution; transfer the mixed solution to a 200 mL polytetrafluoroethylene-lined high-temperature and high-pressure reactor, and react at 150 °C for 12 h with a stirring rate of 200 rpm; the pre-treatment steps of the activated carbon powder are the same as in Example 1; (3) After the reaction is completed, the supernatant is separated by centrifugation, the precipitate is collected, and the precipitate is washed three times by centrifugation with N,N-dimethylformamide and anhydrous ethanol. The precipitate is then soaked in methanol solution for 24 h, and the methanol is replaced every 12 h. Finally, it is dried in a forced-air drying oven at 60 ℃ for 12 h. After it is naturally cooled to room temperature, it is taken out, ground and passed through a 200-mesh sieve to obtain the iron-nickel bimetallic organic framework composite carbon electrode material.

[0026] Example 3 A method for preparing an iron-nickel bimetallic organic framework composite carbon electrode material (FeNi-MOF / AC) specifically includes the following steps: (1) Weigh 2.8512 g (12 mmol) nickel dichloride hexahydrate and 0.9504 g (3.52 mmol) ferric chloride hexahydrate into a beaker, then add 132 mL N,N-dimethylformamide, 9 mL deionized water and 9 mL anhydrous ethanol into the beaker and stir until homogeneous. Then sonicate to ensure complete dissolution and prepare a mixed solvent. (2) Add 8 g of pre-treated activated carbon powder and 0.2 g of polyvinylpyrrolidone dispersant to the mixed solvent, and sonicate to form a homogeneous solution; then add 2.658 g (16 mmol) of terephthalic acid, and continue sonication to form a homogeneous mixed solution; transfer the mixed solution to a 200 mL polytetrafluoroethylene-lined high-temperature and high-pressure reactor, and react at 125 °C for 15 h with a stirring rate of 200 rpm; the pre-treatment steps of the activated carbon powder are the same as in Example 1; (3) After the reaction is completed, the supernatant is separated by centrifugation, the precipitate is collected, and the precipitate is washed three times by centrifugation with N,N-dimethylformamide and anhydrous ethanol. The precipitate is then soaked in methanol solution for 24 h, and the methanol is replaced every 12 h. Finally, it is dried in a forced-air drying oven at 60 ℃ for 12 h. After it is naturally cooled to room temperature, it is taken out, ground and passed through a 200-mesh sieve to obtain the iron-nickel bimetallic organic framework composite carbon electrode material.

[0027] Example 4 The preparation method of the iron-nickel bimetallic organic framework composite carbon electrode includes the following steps: (1) The prepared iron-nickel bimetallic organic framework composite carbon electrode material (FeNi-MOF / AC) was used as the electrode active material, acetylene black as the conductive agent, and polyvinylidene fluoride as the binder. The three were placed in a sample bottle in a mass ratio of 8:1:1 and ground with a hand grinder for 10 min to mix them evenly. An appropriate amount of N-methylpyrrolidone solution was added to the mixture and magnetically stirred for 12 h to obtain a uniform electrode slurry. (2) The electrode slurry was uniformly coated on an 11×11 cm titanium plate (the effective coating area is 7×7 cm) using a four-sided coating preparation device. The electrode thickness was 150 μm. The electrode was dried at 60 °C for 12 h.

[0028] Example 5 The method for preparing activated carbon electrodes is the same as in Example 4, except that the active material used for the electrodes is changed to activated carbon.

[0029] Example 6 Capacitor deionization device: (1) A simplified diagram of the CDI module structure is shown below. Figure 1As shown, a hybrid capacitor deionization module is used to assemble an asymmetric electrode. The first current collector 3 is an activated carbon electrode prepared in Example 5, serving as the cathode. The second current collector 9 is an iron-nickel bimetallic organic framework composite carbon electrode prepared in Example 4, serving as the anode. A cation exchange membrane 4 and an anion exchange membrane 8 are set in front of the cathode and anode plates. The CDI module mainly consists of glass end plates, current collectors coated with electrode material 16, cation and anion exchange membranes, silicone gaskets, and plastic partitions 6. The first glass end plate 1 and the second glass end plate 11 serve as the electrode end plates, and the electrodes are fixed by screws. The first glass end plate 1 is provided with a water inlet 12, and the second glass end plate 11 is provided with a water outlet 13 to ensure water circulation in the electrode module. The water inlet 12 is at the bottom. After the liquid to be treated enters the CDI module, it flows from bottom to top through the water channel left by the plastic partition 6 and is finally discharged from the water outlet 13 at the top. The second current collector 9 and the first current collector 3 are made of titanium plates, which serve two purposes: to provide a substrate for coating the electrode material and to transmit current. Four silicone gaskets (first silicone gasket 2, second silicone gasket 5, third silicone gasket 7, and fourth silicone gasket 10) are positioned between the glass end plate and the current collector, and between the current collector and the plastic separator 6, ensuring good sealing of the electrode module. The plastic separator 6 provides a water flow channel while preventing short circuits between the two electrodes. The cation exchange membrane 4 and the anion exchange membrane 8 only allow specific ions to pass through, thereby avoiding co-ion effects.

[0030] (2) The capacitor deionization system adopts a circulating flow mode. The entire device consists of a DC power supply, a CDI module, a solution to be treated, and a peristaltic pump. The DC power supply applies a DC voltage of 1.5 V to the two electrodes through the first tab 14 of the first current collector 3 and the second tab 15 of the second current collector 9. The peristaltic pump pumps the solution into the capacitor deionization module at a flow rate of 10 mL / min. The solution enters the system through the inlet 12, flows through the coating area of ​​the two electrodes, and then flows out of the electrode module through the outlet 13 and is pumped back to the original beaker by another peristaltic pump.

[0031] Example 7 Composite electrode material capacitive deionization control of extracellular fluid in water sulA Resistance gene effect test (1) The iron-nickel bimetallic organic framework composite carbon electrode material prepared in Example 1 was used to prepare a capacitor deionization device according to the preparation methods in Examples 4-6, for use in extracellular fluid in water. sulA The specific steps of the resistance gene removal experiment are as follows: A sulfonamide antibiotic resistance gene with a total length of 298 bp was selected. sulA The study subject was a 50 mL solution containing an extracellular resistance gene. sulA The abundance of resistance genes at the inlet of the ultrapure water containing DNA fragments was 1.515 × 10⁻⁶. 6The solution to be treated was passed through the capacitive deionization device at a flow rate of 10 mL / min. A DC voltage of 1.5 V was applied to the two electrodes using a DC power supply. The device was run for 30 min, and water samples were collected every 5 min, with 100 μL of water sample collected each time. As a control group, the device was run for 30 min without power and water samples were collected at the corresponding time points.

[0032] The eARGs in the water sample were absolutely quantified using quantitative polymerase chain reaction (qPCR). To determine the removal effect of capacitor deionization, the removal effect of resistance genes was expressed as Log(C / C0), and the removal rate was (C0-C) / C0×100%, where C0 is the number of gene copies (copies / mL) carried in the system before the initial treatment, and C represents the number of gene copies (copies / mL) remaining in the water sample after t minutes of treatment.

[0033] Sulfonamide antibiotic resistance genes sulA The primer sequences are as follows; sulA-F: 5'-TCTTGAGCAAGCACTCCAGCAG-3' (SEQ ID No. 1); sulA-R: 5'-TCCAGCCTTAGCAACCACATGG-3' (SEQ ID No. 2).

[0034] (2) Methods for testing resistance genes qPCR test sample preparation procedure: Under light-protected conditions, add 2 μL DNA template, 10 μL 2× SGExcel FastSYBR Mixture, 0.2 μL 100× ROX Reference Dye, 0.4 μL forward and reverse primers (10 μM), and 7.0 μL sterile enzyme-free water to each well of a 96-well plate, centrifuge to mix, and place in the dark before testing.

[0035] The qPCR test procedure was set as follows: first, pre-denaturation was performed at 95 °C for 3 min, then denaturation was performed at 95 °C for 5 s, followed by annealing at 60 °C for 20 s and extension at 60 °C for 20 s, for a total of 40 cycles; the Ct value of the sample was obtained, and the concentration of the resistance gene in the sample was obtained according to the standard curve.

[0036] Received sulA The standard curve (1) for the resistance gene is (R 2 = 0.9992): y = -3.6853x + 34.761(1) Where y is the Ct value and x is the logarithm of the abundance of the DNA template gene.

[0037] Based on the above standard curve, the results after processing for different times were obtained. sulA Gene abundance, such as Figure 4 As shown, after different processing times sulA The removal rate of resistance genes, such as Figure 5 As shown. Gene abundance decreased rapidly in the initial stage of treatment; after applying a voltage of 1.5 V to the device for 5 minutes... sulA Gene abundance decreased by (0.64±0.07) log, with a removal rate of 77.13%, compared to the control group. sulA The gene abundance decreased by only (0.08±0.05) log, with a removal rate of 16.82%, far lower than that of the experimental group. At 30 min, the experimental group... sulA The gene abundance decreased by (1.39±0.02) log, and the removal efficiency reached 95.93%. After the capacitor deionization device was powered on, it effectively removed extracellular resistance genes in the water. sulA The control effect was significantly improved (p<0.001), indicating that the iron-nickel bimetallic organic framework composite carbon electrode material can effectively control extracellular molecules in the aquatic environment. sulA Resistance genes.

[0038] Example 8 Composite electrode material capacitive deionization control of extracellular fluid in water chL Resistance gene effect test (1) The iron-nickel bimetallic organic framework composite carbon electrode material prepared in Example 2 was used to prepare a capacitor deionization device according to the preparation methods in Examples 4-6, for use in extracellular fluid in water. chL The specific steps of the resistance gene removal experiment are as follows: A chloramphenicol antibiotic resistance gene with a total length of 268 bp was selected. chL The study subject was a 50 mL solution containing an extracellular resistance gene. chL The abundance of resistance genes at the inlet of the ultrapure water containing DNA fragments was 6.35 × 10⁻⁶. 5 The solution to be treated was passed through the capacitive deionization device at a flow rate of 10 mL / min. A DC voltage of 1.5 V was applied to the two electrodes using a DC power supply. The device was run for 30 min, and water samples were collected every 5 min, with 100 μL of water sample collected each time. As a control group, the device was run for 30 min without power and water samples were collected at the corresponding time points.

[0039] The eARGs in the water sample were absolutely quantified using quantitative polymerase chain reaction (qPCR). To determine the removal effect of capacitor deionization, the removal effect of resistance genes was expressed as Log(C / C0), and the removal rate was (C0-C) / C0×100%, where C0 is the number of gene copies (copies / mL) carried in the system before the initial treatment, and C represents the number of gene copies (copies / mL) remaining in the water sample after t minutes of treatment.

[0040] Chloramphenicol antibiotic resistance gene chL The primer sequences are as follows; chL-F: 5'-GGAGTGAATACCACGACGAT-3' (SEQ ID No. 3); chL-R: 5'-ACGGCATGATGAACCTGAAT-3' (SEQ ID No. 4).

[0041] (2) Methods for testing resistance genes qPCR test sample preparation procedure: Under light-protected conditions, add 2 μL DNA template, 10 μL 2× SGExcel FastSYBR Mixture, 0.2 μL 100× ROX Reference Dye, 0.4 μL forward and reverse primers (10 μM), and 7.0 μL sterile enzyme-free water to each well of a 96-well plate, centrifuge to mix, and place in the dark before testing.

[0042] The qPCR test procedure was set as follows: first, pre-denaturation was performed at 95 °C for 3 min, then denaturation was performed at 95 °C for 5 s, followed by annealing at 60 °C for 20 s and extension at 60 °C for 20 s, for a total of 40 cycles; the Ct value of the sample was obtained, and the concentration of the resistance gene in the sample was obtained according to the standard curve.

[0043] Received chL The standard curve (2) for the resistance gene is (R 2 = 0.999): y = -3.8218x + 35.507(2) Where y is the Ct value and x is the logarithm of the abundance of the DNA template gene.

[0044] Based on the above standard curve, the results after processing for different times were obtained. chL Gene abundance, such as Figure 6 As shown, after different processing times chL Resistance gene removal rate, such as Figure 7 As shown. Initial stage of processing. chLGene abundance decreased rapidly after applying a 1.5 V voltage to the device for 5 minutes. chL Gene abundance decreased by (0.56±0.08) log, with a removal rate of 72.82%, compared to the control group. chL The gene abundance decreased by only (0.0065±0.03) log, with a removal rate of 1.48%, far lower than that of the experimental group; at the end of the experiment, the experimental group... chL The gene abundance decreased by (1.49±0.06) log, and the removal efficiency reached 96.80%. After the capacitor deionization device was powered on, it effectively removed extracellular resistance genes in the water. chL The control effect was significantly improved (p<0.001), indicating that the iron-nickel bimetallic organic framework composite carbon electrode material can effectively control extracellular molecules in the aquatic environment. chL Resistance genes.

[0045] Example 9 Composite electrode material capacitive deionization control of extracellular fluid in water tetL Resistance gene effect test (1) The iron-nickel bimetallic organic framework composite carbon electrode material prepared in Example 3 was used to prepare a capacitor deionization device according to the preparation methods in Examples 4-6, for use in extracellular fluid in water. tetL The specific steps of the resistance gene removal experiment are as follows: A tetracycline antibiotic resistance gene with a total length of 267 bp was selected. tetL The study subject was a 50 mL solution containing an extracellular resistance gene. tetL The abundance of resistance genes at the inlet of the ultrapure water containing DNA fragments was 1.65 × 10⁻⁶. 7 The solution to be treated was passed through the capacitive deionization device at a flow rate of 10 mL / min. A DC voltage of 1.5 V was applied to the two electrodes using a DC power supply. The device was run for 30 min, and water samples were collected every 5 min, with 100 μL of water sample collected each time. As a control group, the device was run for 30 min without power and water samples were collected at the corresponding time points.

[0046] The eARGs in the water sample were absolutely quantified using quantitative polymerase chain reaction (qPCR). To determine the removal effect of capacitor deionization, the removal effect of resistance genes was expressed as Log(C / C0), and the removal rate was (C0-C) / C0×100%, where C0 is the number of gene copies (copies / mL) carried in the system before the initial treatment, and C represents the number of gene copies (copies / mL) remaining in the water sample after t minutes of treatment.

[0047] Tetracycline antibiotic resistance genes tetL The primer sequences are as follows; tetL-F: 5'-TCGTTAGCGTGCTGTCATTC-3' (SEQ ID No. 5); tetL-R: 5'-GTATCCCACCAATGTAGCCG-3' (SEQ ID No. 6).

[0048] (2) Methods for testing resistance genes qPCR test sample preparation procedure: Under light-protected conditions, add 2 μL DNA template, 10 μL 2× SGExcel FastSYBR Mixture, 0.2 μL 100× ROX Reference Dye, 0.4 μL forward and reverse primers (10 μM), and 7.0 μL sterile enzyme-free water to each well of a 96-well plate, centrifuge to mix, and place in the dark before testing.

[0049] The qPCR test procedure was set as follows: first, pre-denaturation was performed at 95 °C for 3 min, then denaturation was performed at 95 °C for 5 s, followed by annealing at 60 °C for 20 s and extension at 60 °C for 20 s, for a total of 40 cycles; the Ct value of the sample was obtained, and the concentration of the resistance gene in the sample was obtained according to the standard curve.

[0050] Received tetL The standard curve (3) for the resistance gene is (R 2 = 0.998): y = -4.0643x + 39.354(3) Where y is the Ct value and x is the logarithm of the abundance of the DNA template gene.

[0051] Based on the above standard curve, the results after processing for different times were obtained. tetL Gene abundance, such as Figure 8 As shown, after different processing times tetL Resistance gene removal rate, such as Figure 9 As shown. Gene abundance decreased rapidly in the initial stage of treatment; after applying a voltage of 1.5 V to the device for 5 minutes... tetL The gene abundance decreased by (0.45±0.0003) log, with a removal rate of 64.91%, compared to the control group. tetL The gene abundance decreased by only (0.01±0.03) log, with a removal rate of 3.8%, far lower than that of the experimental group; at 30 min, the experimental group... tetL The gene abundance decreased by (1.26±0.03) log, and the removal efficiency reached 94.52%. After the capacitor deionization device was powered on, it effectively removed extracellular resistance genes in the water. tetLThe control effect was significantly improved (p<0.001), indicating that the iron-nickel bimetallic organic framework composite carbon electrode material can effectively control extracellular molecules in the aquatic environment. tetL Resistance genes.

[0052] Although specific embodiments of the present invention have been described in detail with reference to examples, they should not be construed as limiting the scope of protection of this patent. Various modifications and variations that can be made by those skilled in the art without inventive effort within the scope described in the claims are still within the scope of protection of this patent.

Claims

1. A method for preparing an electrode material, characterized in that, Includes the following steps: (1) Iron salt and nickel salt are dissolved in a mixed solvent to prepare a mixed solution; the ratio of iron salt, nickel salt and mixed solvent is 1-2.5 mmol: 5-7 mmol: 68-80 mL, the mixed solvent is composed of N,N-dimethylformamide, anhydrous ethanol and deionized water; the volume ratio of N,N-dimethylformamide, anhydrous ethanol and deionized water in the mixed solvent is 60-70: 4-5: 4-5; (2) Add activated carbon powder, polyvinylpyrrolidone and terephthalic acid to the mixed solution, and then react at 125~150℃ for 12~15 h; the ratio of activated carbon powder, polyvinylpyrrolidone and terephthalic acid is 3-8 g:0.05-0.2 g:8-16 mmol; (3) Separate the precipitate from the product after step (2) and wash it. Then soak the precipitate in methanol, dry it and grind it to obtain the final product.

2. The method for preparing the electrode material according to claim 1, characterized in that: The iron salt is ferric chloride, and the nickel salt is nickel dichloride.

3. The method for preparing the electrode material according to claim 1, characterized in that, The proportions of each raw material are as follows: 66 mL of N,N-dimethylformamide, 4.5 mL of anhydrous ethanol, 4.5 mL of deionized water, 1.76 mmol of ferric chloride hexahydrate, 6 mmol of nickel dichloride hexahydrate, 4 g of activated carbon powder, 0.1 g of polyvinylpyrrolidone, and 8 mmol of terephthalic acid.

4. The iron-nickel bimetallic organic framework composite carbon electrode material prepared by the method of any one of claims 1 to 3.

5. A capacitor deionization device, characterized in that: The capacitor deionization device includes an anode made of the iron-nickel bimetallic organic framework composite carbon electrode material as described in claim 4 and a cathode made of activated carbon material.

6. The capacitor deionization device according to claim 5, characterized in that, The anode is prepared in the following steps: (1) The iron-nickel bimetallic organic framework composite carbon electrode material, acetylene black and polyvinylidene fluoride are mixed evenly in a mass ratio of 8:1:1, and then N-methylpyrrolidone solution is added to the mixture and stirred evenly to obtain electrode slurry. (2) The electrode paste is evenly coated on the titanium plate and dried.

7. The use of the capacitor deionization device according to any one of claims 5 to 6 in removing antibiotic resistance genes from water.

8. The application according to claim 7, characterized in that: The antibiotic resistance gene is a sulfonamide antibiotic resistance gene, a chloramphenicol antibiotic resistance gene, or a tetracycline antibiotic resistance gene.

9. The application according to claim 8, characterized in that: When removing antibiotic resistance genes, a DC voltage of 1.5 V is applied to the two electrodes of the capacitor deionization device.

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