Active oxygen electrode materials for water purification and disinfection, their preparation methods and applications

Abstract

This invention discloses an active oxygen electrode material for water purification and disinfection, its preparation method, and its application, belonging to the field of drinking water purification technology. The electrode material is based on Ox-CNHs nano-conductive particles obtained from treated single-walled carbon nanoparticles, combined with nitrogen-doped polyaniline and other components. It innovatively utilizes aniline and fine coal gasification slag, and is prepared through a special process. Its unique structure results in excellent oxygen adsorption and conductivity, enabling efficient generation of active oxygen groups. It also possesses water and air purification and disinfection capabilities, can be reused multiple times, reducing costs and achieving high-value utilization of solid waste. When this electrode material is used as the anode and cathode in an electrochemical water purification and disinfection device, its excellent conductivity and catalytic activity, combined with the synergistic effect of the anode and cathode in the electrochemical reactor and the flow channel plate guiding water flow, ensures sufficient contact between the water and the electrodes, significantly improving the water purification and disinfection efficiency. It shows broad prospects in the fields of water and air purification and environmental protection.

Description

Technical Field

[0001] This invention relates to the technical field of electrochemical advanced oxidation electrode material design and application, and particularly to active oxygen electrode materials for water purification and disinfection, their preparation methods and applications. Background Technology

[0002] The presence of pathogens such as bacteria, fungi, viruses, and parasites in water bodies seriously threatens human health and safety. Disinfection of water bodies is a crucial measure to effectively eliminate these pathogens and ensure water quality safety. Currently, in the field of traditional water disinfection, chemical disinfectants dominate due to their mature technology and wide application range. Liquid chlorine, chloramine, ozone, and chlorine dioxide are among the most common chemical disinfectants. Traditional disinfection technologies have demonstrated many advantages in practical applications. They can effectively kill most pathogens, ensuring that the microbiological indicators of treated water meet safety standards, providing basic protection for residents' drinking water safety. Furthermore, by retaining a residual amount of disinfectant, it plays a continuous role in preventing microbial contamination in water distribution pipelines and containers after the water leaves the plant, greatly reducing the probability of waterborne diseases and playing an irreplaceable role in public health. However, since the 1970s, the potential risks of traditional disinfection technologies have gradually become apparent. Researchers have successively identified and recognized dozens of disinfection byproducts, which are produced by the chemical reaction between disinfectant reagents and organic matter in water. Numerous studies have shown that these disinfection byproducts pose significant risks to human health, potentially causing a range of health problems such as increased cancer incidence and reproductive and developmental abnormalities. This discovery means that while traditional disinfection technologies ensure water safety, they also introduce new health risks, prompting the search for safer and more efficient water disinfection technologies.

[0003] In recent years, electrochemical methods have demonstrated enormous potential in environmental remediation, particularly in the significant progress made in degrading organic pollutants. With the continuous development of various new materials and the increasing maturity of technologies that use electric current to replace traditional chemical oxidants or reducing agents, electrochemical methods are gradually being applied in water disinfection. The highly efficient sterilization capability of electrochemical disinfection technology mainly relies on the synergistic effect of direct and indirect oxidation reactions occurring on the electrode surface. The basic principle is that during the electric field reaction, various substances with strong bactericidal activity are generated. On the one hand, reactive oxygen species, such as ·OH, ·O, O3, and H2O2, are generated. These reactive oxygen species have extremely high chemical activity and can rapidly destroy the cell structure of microorganisms. On the other hand, other active chemical substances, such as Cl2, HOCl, and ClO3, are also generated, further enhancing the bactericidal effect. Simultaneously, permanent pores are formed in the cell wall under the induction of the electric field. These active substances enter the microorganisms through these pores, causing cell damage and thus achieving sterilization.

[0004] While electrochemical disinfection technology boasts powerful capabilities in removing pollutants and inactivating organisms, and offers numerous advantages such as high efficiency, wide temperature range, rapid start-up, simple operation, and ease of automation, its promotion and application face several pressing challenges. Electrode materials are a key limiting factor. Currently used electrode materials suffer from low efficiency in generating active groups, resulting in insufficient quantities of highly bactericidal substances produced during disinfection, thus affecting the disinfection effect. Furthermore, their short lifespan necessitates frequent replacements, increasing operating costs and maintenance complexity. The high cost of electrode materials also restricts the widespread adoption and application of electrochemical technology in water purification and disinfection. Therefore, developing a simple electrode and its reaction device that can significantly generate highly bactericidal active oxygen is of paramount practical significance for overcoming the existing bottlenecks in electrochemical disinfection technology and promoting its widespread application in water purification and disinfection. Summary of the Invention

[0005] To address the health risks associated with disinfection byproducts in traditional disinfection technologies, and the limitations of electrochemical disinfection technologies such as low efficiency in generating active groups, short lifespan, and high cost of electrode materials, this invention provides an active oxygen electrode material for water purification and disinfection, along with its preparation method and application. This solves the problems of low efficiency in generating active groups, short lifespan, and high cost of existing electrode materials.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] This invention provides a method for preparing an active oxygen electrode material for water purification and disinfection, comprising:

[0008] S1, Prepare single-walled carbon nanotubes (Ox-CNHs) conductive particles loaded with oxygen-containing functional groups;

[0009] S2, single-walled carbon nanotubes (Ox-CNHs) conductive particles loaded with oxygen-containing functional groups, coal gasification slag, tartaric acid, and isopropanol are stirred under vacuum, and 1L of deionized water is added to make up the volume to obtain a single-walled carbon nanotube (Ox-CNHs) solution loaded with oxygen-containing functional groups.

[0010] S3, nitrogen source, aniline and reducing agent are added to a solution of single-walled carbon nanotubes (Ox-CNHs) loaded with oxygen-functional groups, heated to dissolve, and after hydrothermal reaction, a composite solution of aniline and single-walled carbon nanotubes loaded with oxygen-functional groups (PANI@Ox-CNHs) is obtained;

[0011] The nitrogen source is any one or a combination of urea or ammonium nitrate, and the reducing agent is any one of sodium nitrite, hydroxylamine hydrochloride, and sodium citrate.

[0012] S4. Carbon-based materials are added to a composite solution of aniline and single-walled carbon nanotubes loaded with oxygen-containing functional groups (PANI@Ox-CNHs) and electropolymerized to obtain electrode precursor materials.

[0013] The carbon-based material is any one of activated carbon fiber, carbon felt graphite felt, carbon paper, and carbon fiber cloth;

[0014] S5. After sequentially subjecting the electrode precursor material to microwave irradiation and freeze-drying, an active oxygen electrode material for water purification and disinfection is obtained.

[0015] S1 specifically includes: adding single-walled carbon nano-angle materials to an acid solution, ultrasonically stirring, vacuum drying, and then calcining to obtain single-walled carbon nano-angle (Ox-CNHs) conductive particles loaded with oxygen-containing functional groups.

[0016] The mass ratio of the single-walled carbon nanotube angle material to the acid solution is 1~5:5~10, the calcination temperature is 300 ℃~700 ℃, and the calcination time is 1 h~3 h.

[0017] Further, the acid solution is one or a combination of two of the following: an 80% sulfuric acid solution or a 60% nitric acid solution; the mass ratio of the single-walled carbon nanotube material to the acid solution is 1~5:5~10.

[0018] Furthermore, the calcination process using a tube furnace employs a heating program of 10 °C / min and an N2 flow rate of 20 mL / min.

[0019] In S2, the mass ratio of the oxygen-containing single-walled carbon nanotube (Ox-CNHs) conductive particles, coal gasification slag, tartaric acid, and isopropanol is 0.2~1:1~10:0.5~5:1~5; the vacuum heating temperature is 70 ℃~120 ℃, and the heating time is 1 h~4 h.

[0020] In S3, the mass ratio of the nitrogen source, aniline, reducing agent, and single-walled carbon nanotubes (Ox-CNHs) solution loaded with oxygen-containing functional groups is 1~6:1~10:2~5:10~50, the hydrothermal reaction temperature is 80 ℃~150 ℃, the reaction time is 0.5 h~5 h, and the reaction pressure is 2 MPa~6 MPa.

[0021] Furthermore, the calcination process using a tube furnace employs a heating program of 10 °C / min and an N2 flow rate of 20 mL / min.

[0022] In S4, the mass ratio of the carbon-based material to the composite solution of aniline and single-walled carbon nanotubes loaded with oxygen-containing functional groups (PANI@Ox-CNHs) is 1~10:30~100.

[0023] In S4, the electropolymerization reaction uses the carbon-based material as the working electrode, a platinum sheet as the counter electrode, a DC power supply, constant current control, and a current of 0.1A to 12A. The reference electrode is a saturated calomel electrode.

[0024] In S5, the microwave drying conditions are: 500 W~1500 W, 90 ℃~140 ℃, and N2 gas flow rate of 5 L / min~25 L / min for 0.5 h~6 h. The freeze-drying conditions are: 500 W~1200 W, -20 ℃~-5 ℃ for 20 min~30 min.

[0025] The active oxygen electrode material for water purification and disinfection prepared by the aforementioned method has a specific surface area of ​​2000 cm². 2 / g~3900 cm 2 / g, hydrophilic angle 60°~80°, porosity 70%~95%, average pore size 0.18 μm~3.6 μm, pore volume 0.20 cm³ / g 3 / g~0.65 cm 3 / g.

[0026] The application of the active oxygen electrode material for water purification and disinfection in the preparation of an electrochemical water purification and disinfection device uses the active oxygen electrode material for water purification and disinfection as the cathode.

[0027] An electrochemical water purification and disinfection device includes an electrochemical reactor with an inlet and an outlet. A cathode fixing plate and an anode fixing plate are disposed within the electrochemical reactor to fix the cathode and anode. The cathode and anode are made of the active oxygen electrode material used for water purification and disinfection. A flow channel plate is provided between the cathode fixing plate and the anode fixing plate to guide the flow path of water within the electrochemical reactor.

[0028] Compared with the prior art, the present invention achieves the following technical effects:

[0029] This invention provides a novel method for preparing active oxygen electrode materials for water purification and disinfection. Single-walled carbon nanotubes are processed to obtain Ox-CNHs conductive nanoparticles, which possess unique structures and electrical properties, providing a good conductive foundation for the electrode material. The method utilizes conductive particles with extremely low resistance and nitrogen-doped polyaniline polymers as the main components, forming the basis of a three-dimensional composite conductive material. This enables the efficient electrochemical generation of active oxygen groups. The invention innovatively uses aniline (polymeric conductive) and coal gasification fine slag (porous) as conductive aids and pore-forming agents, ensuring uniform dispersion of conductive particles without damaging the nanoparticle surface. The resulting active oxygen electrode material exhibits significant advantages in the production of oxygen-active groups (such as superoxide radicals and singlet oxygen) and possesses excellent purification and disinfection performance. It can be widely applied in water purification and disinfection fields such as drinking water treatment and industrial wastewater treatment, effectively removing various pollutants and microorganisms from water and ensuring water quality safety.

[0030] Furthermore, the corner defect structure and curvature effect of single-walled carbon nanotubes promote oxygen adsorption and water-reactive groups. Utilizing the cross-linked filamentary structure generated during the electropolymerization of polyaniline, the carbon gas layer formed during heating is "retained" in situ within CNHs, enabling the efficient deposition of the nanoscale active catalytic layer formed by conductive particles on the surface of coal gasification slag and within the fibrous multi-channel carbon-based material. This process also ensures uniform loading and good oxygen adsorption and conductivity for generating oxygen-reducing active groups. Microwave radiation and ultra-low temperature freeze-drying technologies are employed to achieve integrated heating and freeze-drying, enhancing the spatial reaction and fibrous microchannel structure of the material. The unique effect of the microwave electromagnetic field, combined with its special drying method, increases the number of catalytic reaction active sites and improves the efficiency of oxygen reduction active group generation.

[0031] Furthermore, the electrode material is prepared by a specific combination of nano-conductive particles, polyaniline, nitrogen source, and coal gasification fine slag, exhibiting excellent conductivity and catalytic activity. Utilizing the high specific surface area and excellent conductivity of the coal gasification fine slag not only reduces the preparation cost of the electrode material but also enables the high-value utilization of solid waste, reducing the amount of solid waste stockpiled. The polyaniline polymer provides good support and stability, while its special structure also provides more electron transfer space and electrochemical reaction active sites for the electrochemical reaction.

[0032] The present invention provides an active oxygen electrode material for water purification and disinfection. This active oxygen electrode material is composed of Ox-CNHs nano-conductive particles and a polyaniline nitrogen-doped electrocatalytic active layer. This active oxygen electrode material not only has excellent conductivity and catalytic activity, but the polymer material also plays a supporting and stabilizing role, providing more electron transfer space and electrocatalytic active sites, significantly improving the efficiency of electrocatalytic oxygen and water to generate oxygen active groups. At the same time, this active oxygen electrode material also has the ability to disinfect and purify water and air, which is helpful for environmental protection and wastewater treatment. The removal effect is stable before and after use, which is conducive to repeated use and reduces the cost of use.

[0033] The application provided by this invention is that the active oxygen electrode material of this invention has highly efficient oxygen-generating active groups and water and air disinfection and purification capabilities. Moreover, the removal effect is stable before and after use, which is conducive to repeated use. This provides a broad application prospect for this material in the fields of water disinfection and purification, air disinfection and purification, and environmental protection.

[0034] The electrochemical water purification and disinfection device provided by this invention uses common metal plate materials (titanium, stainless steel, nickel, or copper) for the anode and active oxygen electrode materials for water purification and disinfection for the cathode. This electrode material possesses excellent conductivity and catalytic activity, efficiently generating active oxygen groups. These active oxygen groups can effectively kill viruses, bacteria, and other microorganisms in the water and degrade organic pollutants. In the electrochemical reactor, the anode and cathode work synergistically, fully utilizing the performance advantages of the electrode materials and significantly improving the device's water purification and disinfection efficiency. The flow channel plate between the cathode and anode fixing plates guides the flow path of the water within the electrochemical reactor. A reasonable flow path ensures sufficient contact between the water and the electrodes, guaranteeing that pollutants and microorganisms in the water have enough time and opportunity to react with the active oxygen groups generated by the electrodes, further improving the purification and disinfection effect. Simultaneously, the oxygen-active cathode can efficiently utilize dissolved oxygen in the water to efficiently generate oxygen-active groups, eliminating the need for external aeration and reducing aeration costs. Attached Figure Description

[0035] Figure 1 The images shown are electron microscope scans of the surface of the active oxygen electrode material for water purification and disinfection prepared in Example 1 of the present invention, wherein A is an electron microscope scan image magnified 20,000 times and B is an electron microscope scan image magnified 500,000 times.

[0036] Figure 2 This is a physical image of the active oxygen electrode material for water purification and disinfection prepared in Example 2 of the present invention;

[0037] Figure 3 Hydrophilic angle test of the active oxygen electrode material for water purification and disinfection prepared in Example 3 of the present invention and the carbon-based material without nano-conductive particles.

[0038] Figure 4 A comparison diagram of active oxygen production between the active oxygen electrode material for water purification and disinfection prepared in Example 4 of the present invention and the carbon-based material without nano-conductive particles.

[0039] Figure 5 The COD treatment effect diagram of the active oxygen electrode material for water purification and disinfection prepared in Example (2) 5 of this invention;

[0040] Figure 6 This is a structural diagram of the electrochemical water purification and disinfection device of the present invention, wherein A is a top view of the electrochemical water purification and disinfection device, B is a three-dimensional schematic diagram, C and D are exploded three-dimensional views, 1 represents the inlet, 2 represents the outlet, 3 represents the flow channel plate, 4 represents the cathode fixing plate, 5 represents the anode fixing plate, and 6 represents the electrochemical reactor. Detailed Implementation

[0041] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0042] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0043] Unless otherwise specified, all experimental materials used in this invention are commercially available products well known to those skilled in the art.

[0044] Specific surface area: refers to the total surface area per unit mass of a substance. The commonly used detection method is the BET method.

[0045] Porosity refers to the percentage of pore volume in a material's total volume, and can be measured using mercury porosimetry or gas adsorption methods combined with relevant models. Mercury porosimetry measures the volume of mercury entering the pores under different pressures to obtain the pore diameter distribution, and then calculates the porosity.

[0046] Pore ​​volume refers to the total volume of pores per unit mass of material, and can be detected using mercury porosimetry or gas adsorption methods. Mercury porosimetry: In mercury porosimetry, the pore volume is obtained by measuring the total volume of mercury entering the pores of the sample and then dividing it by the mass of the sample.

[0047] Ox-CNHs: Single-walled carbon nanotubes (CNHs for short) are single-walled carbon nanotubes loaded with oxygen-containing functional groups.

[0048] PANI@Ox-CNHs: PANI is the abbreviation for phenylamine. A phenylamine and single-walled carbon nanotubes loaded with oxygen-containing functional groups form a composite solution, which is denoted as PANI@Ox-CNHs.

[0049] I. Specific Implementation Cases

[0050] Example 1

[0051] This embodiment provides an active oxygen electrode material for water purification and disinfection, and the specific preparation process is as follows:

[0052] 1.0 g of single-walled carbon nanotubes (CNHs) were weighed and added to 5.0 g of sulfuric acid solution (mass fraction of 80%). The mixture was ultrasonically stirred and vacuum dried at 80 °C for 3 h. After drying, the sample was quickly transferred to a muffle furnace and calcined at 300 °C for 1 h. After calcination, the sample was naturally cooled to room temperature to obtain Ox-CNHs nano-conductive particles.

[0053] Weigh 0.2 g of Ox-CNHs nano-conductive particles, 1.0 g of coal gasification fine slag and 0.5 g of tartaric acid, measure 1 mL of isopropanol, add them to a vacuum heating device, set the heating temperature to 70 ℃, heat and stir for 1 h, take out the mixture, make up to 1000 mL with deionized water, stir evenly to obtain Ox-CNHs solution;

[0054] Weigh 1.0 g of urea, 1.0 g of aniline (PDMS) and 2.0 g of sodium nitrite, add them to 20 mL of Ox-CNHs solution to obtain a mixed solution. Place the mixed solution in a heating device and heat and stir at 80 °C to dissolve it. Then transfer the solution to a hydrothermal reactor and hydrothermally react at 110 °C and 2 MPa for 0.5 h. After the reaction is completed, allow it to cool naturally to room temperature to obtain a PANI@Ox-CNHs composite solution.

[0055] An activated carbon fiber material with dimensions of 2.5 cm × 4 cm was used as the working electrode, a platinum sheet (2.5 cm × 2.5 cm) was used as the counter electrode, and a saturated calomel electrode was used as the reference electrode. The electrode was installed on an electrochemical workstation. 1.5 g of activated carbon fiber material was added to 50 mL of PANI@Ox-CNHs composite solution. The DC power supply was turned on, and the current was set to 0.1 A in constant current control mode to carry out the electropolymerization reaction. After the reaction was completed, the activated carbon fiber material was removed to obtain the electrode precursor material.

[0056] The electrode precursor material was placed in a microwave drying device and dried for 0.5 h at a microwave power of 500 W, a temperature of 90 ℃, and an N2 gas flow rate of 5 L / min. After microwave drying, the electrode precursor material was quickly transferred to a freeze-drying device and freeze-dried for 20 min at a power of 500 W and a temperature of -20 ℃ to obtain an active oxygen electrode material for water purification and disinfection.

[0057] See appendix Figure 1 The microstructure of the electrode material prepared in this embodiment for water purification and disinfection was tested using scanning electron microscopy. Figure 1 As can be seen, the electrode material prepared in this embodiment for water purification and disinfection has a filamentous structure. The cross-linked filamentous structure is interwoven with CNHs and PDMS, forming a stable cross-linked network. The surface of the filamentous structure is uniformly loaded with a large number of barbed structures. These barbed structures increase the surface roughness and the number of active sites of the material, providing more transport channels and reaction sites for oxygen and water, which is beneficial to the electrochemical reaction and thus improves the oxygen active group generation performance of the material. As can be seen from the figure, the large-pore conductive network nanofiber lines formed by 200 nm PANI nanorods and carbon nanohorn structures are cross-linked. This three-dimensional network structure of polyaniline nitrogen-doped film can reduce internal resistance and improve electron transport, while the large pores increase the low internal resistance caused by oxygen escape, improve electron transport, and increase the available active surface area.

[0058] The specific surface area of ​​the electrode material prepared in this embodiment for water purification and disinfection, as tested using a specific surface area analyzer, was 2000 cm². 2 / g, the porosity, average pore size, and pore volume of the electrode material used for water purification and disinfection in this embodiment were tested using mercury porosimetry. The porosity was 70%, the average pore size was 0.18 μm, and the pore volume was 0.20 cm³. 3 / g.

[0059] See appendix Figure 2The hydrophilicity of the electrode material prepared in this embodiment for water purification and disinfection was tested using a contact angle meter. A control group (carbon fiber material without nano-conductive particles) was also set up. The hydrophilicity angle of the electrode material in this embodiment was 60°, while that of the control carbon fiber material was 120°. These results indicate that the electrode material prepared in this embodiment exhibits better hydrophilicity and media transport performance in water purification and disinfection compared to carbon-based materials. The superior hydrophilicity allows the electrode material to better contact water, improving the adsorption and removal efficiency of viruses and bacteria in the water.

[0060] In summary, this embodiment successfully prepared an electrode material with excellent oxygen-generating active groups for water purification and disinfection. This electrode material exhibits good hydrophilicity, electron transport properties, and mediator transport properties in water treatment. Good hydrophilicity allows the material to better contact with water, improving the adsorption and reaction efficiency for viruses and bacteria in the water. Excellent electron transport properties ensure the efficient conduct of the electrochemical reaction, rapidly converting electrical energy into chemical energy to generate sufficient oxygen-generating active groups for disinfection and purification. Mediator transport properties ensure the smooth transport of reactants and products within the material, improving the overall efficiency of the reaction. This electrode material with excellent oxygen-generating active groups provides new ideas and methods for the development of the water treatment field.

[0061] Example 2

[0062] This embodiment provides an electrode material for water purification and disinfection, and the specific preparation process is as follows:

[0063] 5.0 g of single-walled carbon nanotubes (CNHs) were weighed and added to 10.0 g of sulfuric acid solution (mass fraction 80%). The mixture was ultrasonically stirred and vacuum dried at 80 °C for 3 h. After drying, the sample was quickly transferred to a muffle furnace and calcined at 700 °C for 3 h. After calcination, the sample was naturally cooled to room temperature to obtain Ox-CNHs nano-conductive particles.

[0064] Weigh 1.0 g of Ox-CNHs nano-conductive particles, 10.0 g of coal gasification fine slag and 5.0 g of tartaric acid, and measure 5.0 mL of isopropanol. Add all of them to a vacuum heating device, set the heating temperature to 120 ℃, heat and stir for 4 h, take out the mixture, make up to 1000 mL with deionized water, and stir evenly to obtain Ox-CNHs solution.

[0065] Weigh 6.0 g of urea, 10.0 g of aniline (PDMS) and 15.0 g of sodium nitrite, add them to 30 mL of LOx-CNHs solution to obtain a mixed solution. Place the mixed solution in a heating device and heat and stir at 80 °C to dissolve it. Then transfer the solution to a hydrothermal reactor and hydrothermally react at 150 °C and 6 MPa for 5 h. After the reaction is completed, allow it to cool naturally to room temperature to obtain a PANI@Ox-CNHs composite solution.

[0066] An activated carbon fiber material with a size of 4 cm × 4 cm was used as the working electrode, a platinum sheet (2.5 cm × 2.5 cm) was used as the counter electrode, and a saturated calomel electrode was used as the reference electrode. The electrode was installed on an electrochemical workstation, and 2.2 g of activated carbon fiber material was added to 50 mL of PANI@Ox-CNHs composite solution. The DC power supply was turned on, and the constant current control mode was used to set the current to 12 A to carry out the electropolymerization reaction. After the reaction was completed, the activated carbon fiber material was taken out to obtain the electrode precursor material.

[0067] The electrode precursor material was placed in a microwave drying device and dried for 6 h at a microwave power of 1500 W, a temperature of 140 ℃, and an N2 gas flow rate of 25 L / min. After microwave drying, the electrode precursor material was quickly transferred to a freeze-drying device and freeze-dried for 30 min at a power of 1200 W and a temperature of -5 ℃ to obtain an active oxygen electrode material for water purification and disinfection.

[0068] See appendix Figure 3 The image shown is a physical photograph of the active oxygen electrode material prepared for water purification and disinfection in this embodiment. (See attached image.) Figure 3 It is evident that the uniformly rough surface of the electrode material increases its surface area, providing more adsorption sites for oxygen molecules. Oxygen molecules are more likely to remain and adsorb on the material surface. This adsorption is crucial for the reaction of oxygen-producing active groups, as it promotes effective contact between oxygen molecules and the active sites of the electrode material, thereby improving the performance of oxygen-producing active groups. The rough surface structure also helps improve the stability of the electrode material, reducing aggregation during the reaction process. Furthermore, the specific surface area of ​​the active oxygen electrode material used for water purification and disinfection in this embodiment is tested to be 3900 cm². 2 / g, porosity 95%, average pore size 3.6 μm, pore volume 0.65 cm³. 3 / g, hydrophilic angle is 80°.

[0069] In summary, the electrocatalyst material prepared in this embodiment possesses a uniformly rough surface, providing favorable conditions for in-situ oxygen adsorption. This characteristic not only improves the rate and energy efficiency of the electrocatalytic reaction but also enhances the stability of the catalyst. These properties make this electrode material potentially valuable for applications in the field of electrochemical water purification and disinfection.

[0070] Example 3

[0071] This embodiment provides an active oxygen electrode material for water purification and disinfection, and the specific preparation process is as follows:

[0072] 3.0 g of single-walled carbon nanotubes (CNHs) were weighed and added to 8.0 g of nitric acid solution (60% by mass). The mixture was ultrasonically stirred and vacuum dried at 80 °C for 3 h. After drying, the sample was quickly transferred to a muffle furnace and calcined at 400 °C for 2 h. After calcination, the sample was allowed to cool naturally to room temperature to obtain Ox-CNHs conductive nanoparticles.

[0073] Weigh 0.5 g of Ox-CNHs nano-conductive particles, 1.0 g of coal gasification fine slag and 2.0 g of tartaric acid, and measure 3 mL of isopropanol. Add all of them to a vacuum heating device, set the heating temperature to 80 ℃, heat and stir for 2 h, take out the mixture, and make up to 1000 mL with deionized water. Stir evenly to obtain an Ox-CNHs solution.

[0074] Weigh 3.0 g of urea, 5.0 g of aniline (PDMS), and 6.0 g of sodium nitrite, add them to 80 mL of Ox-CNHs solution to obtain a mixed solution. Place the mixed solution in a heating device and heat and stir at 120 °C to dissolve it. Then transfer the solution to a hydrothermal reactor and hydrothermally react at 110 °C and a reaction pressure of 3 MPa for 3 h. After the reaction is completed, allow it to cool naturally to room temperature to obtain a PANI@Ox-CNHs composite solution.

[0075] A 6 cm × 6 cm carbon felt material was used as the working electrode, a platinum sheet (2.5 cm × 2.5 cm) as the counter electrode, and a saturated calomel electrode as the reference electrode. The electrode was installed on an electrochemical workstation. 4.5 g of carbon felt material was added to 50 mL of PANI@Ox-CNHs composite solution. The DC power supply was turned on, and the current was set to 2 A in constant current control mode to carry out the electropolymerization reaction. After the reaction was completed, the activated carbon fiber material was taken out to obtain the electrode precursor material.

[0076] The electrode precursor material was placed in a microwave drying device and dried for 1 h at a microwave power of 1000 W, a temperature of 100 ℃, and an N2 gas flow rate of 15 L / min. After microwave drying, the electrode precursor material was quickly transferred to a freeze-drying device and freeze-dried for 25 min at a power of 1000 W and a temperature of -15 ℃ to obtain an active oxygen electrode material for water purification and disinfection.

[0077] Further, using an electron paramagnetic resonance (EPR) spectrometer, with 5,5-dimethyl-1-pyrrolline-N-oxide (DMPO) as the decoy and water and methanol as solvents, the PRR signals of oxygen-active groups (superoxide radicals) were detected. The electrode material prepared in Example 3 and the carbon-based material of the comparative example were tested in their respective solvent systems containing DMPO. The results are shown in the appendix. Figure 4 As shown.

[0078] From the appendix Figure 4 Data shows that both Example 3 and the carbon-based material exhibit multiple signal peaks in the magnetic field strength range of approximately 3400 G to 3460 G. The peak positions corresponding to "oxygen-active groups (groups)" are marked in the figures; these peaks represent the paramagnetic resonance signals of oxygen-active groups (such as superoxide radicals). The signal peak intensity corresponding to Example 3 is significantly higher than that of the carbon-based material, indicating a higher relative content of oxygen-active groups generated in Example 3. A 1:2:2:1 ratio of TEMP-1 to TEMP-1 can be observed in Example 3 and the comparative example. 1 O2 characteristic peak, generated in Example 3 1 The relative O2 content is high, increasing by 10 times compared to carbon-based substrates. The electrocatalyst material prepared by this invention shows a significant advantage in the yield of oxygen-active groups. This is due to its unique catalytic performance and optimized structure, which makes the reaction of oxygen on the electrode surface more efficient.

[0079] Example 4

[0080] This embodiment provides an active oxygen electrode material for water purification and disinfection, and the specific preparation process is as follows:

[0081] 4.0 g of single-walled carbon nanotubes (CNHs) were weighed and added to 10.0 g of sulfuric acid solution (mass fraction 80%) and ultrasonically stirred. After vacuum drying at 80 ℃ for 3 h, the sample was quickly transferred to a muffle furnace and calcined at 500 ℃ for 2.5 h. After calcination, the sample was naturally cooled to room temperature to obtain Ox-CNHs nano-conductive particles.

[0082] Weigh 0.8 g of Ox-CNHs nano-conductive particles, 2.0 g of coal gasification fine slag and 4.0 g of tartaric acid, measure 4 mL of isopropanol, add them all to a vacuum heating device, set the heating temperature to 90 ℃, heat and stir for 2.5 h, take out the mixture, make up to 1000 mL with deionized water, stir evenly to obtain Ox-CNHs solution;

[0083] Weigh 4.0 g of urea, 6.0 g of aniline (PDMS), and 8.0 g of sodium nitrite and add them to 80 mL of Ox-CNHs solution to obtain a mixed solution. Place the mixed solution in a heating device and heat and stir at 120 °C to dissolve it. Then transfer the solution to a hydrothermal reactor and react hydrothermally at 120 °C and a reaction pressure of 3.5 MPa for 2.5 h. After the reaction is completed, allow it to cool naturally to room temperature to obtain a PANI@Ox-CNHs composite solution.

[0084] A 6 cm × 6 cm carbon felt material was used as the working electrode, a platinum sheet (2.5 cm × 2.5 cm) as the counter electrode, and a saturated calomel electrode as the reference electrode. The electrode was installed on an electrochemical workstation. 4.5 g of carbon felt material was added to 50 mL of PANI@Ox-CNHs composite solution. The DC power supply was turned on, and the constant current control mode was used to set the current to 0.4 A to carry out the electropolymerization reaction. After the reaction was completed, the activated carbon fiber material was taken out to obtain the electrode precursor material.

[0085] The electrode precursor material was placed in a microwave drying device and dried for 1.5 h at a microwave power of 1100 W, a temperature of 110 ℃, and an N2 gas flow rate of 10 L / min. After microwave drying, the electrode precursor material was quickly transferred to a freeze-drying device and freeze-dried for 30 min at a power of 1100 W and a temperature of -16 ℃ to obtain an active oxygen electrode material for water purification and disinfection.

[0086] The active oxygen electrode material for water purification and disinfection prepared in Example 4 and the traditional carbon-based materials (commercial carbon felt, commercial activated carbon fiber, and commercial graphite felt, purchased from Shanghai Qijie Carbon Co., Ltd.) were used as cathodes (electrode area 10 cm²). 2 Platinum sheets are commonly used as anodes in the market (electrode area 10 cm²). 2 The electrode material (purchased from Tianjin Aida Technology Co., Ltd.) was used. The electrode spacing was 2 cm. 0.05 g of sodium sulfate was added to 100 mL of wastewater discharged from a chemical plant in Shaanxi Province. The potential was 6 V. Electrode materials prepared according to this invention and commercially available carbon-based materials (carbon felt, activated carbon fiber, and graphite felt) were subjected to 120 min electrochemical removal experiments to remove chemical oxygen demand (COD). The COD removal rate was observed and recorded. See Appendix for details. Figure 5 As shown.

[0087] From the appendix Figure 5 Data shows that the electrode material prepared in this embodiment achieved a COD removal rate of 98% when treating organic wastewater. Compared with commercial cathodes (carbon felt, activated carbon fiber, and graphite felt, purchased from Shanghai Qijie Carbon Co., Ltd.), the COD removal rate is only 20%. This demonstrates that the electrode material prepared in this invention shows a significant advantage in removing COD from organic wastewater, with a treatment efficiency increase of 5 times. This proves the high efficiency of the electrode material prepared in this invention in water purification and shows broad application prospects in the field of electrochemical oxygen activated carbon water treatment.

[0088] Example 5

[0089] This embodiment provides an active oxygen electrode material for water purification and disinfection, and the specific preparation process is as follows:

[0090] 6.0 g of single-walled carbon nanotubes (CNHs) were weighed and added to 30.0 g of sulfuric acid solution (mass fraction 80%) for ultrasonic stirring. After vacuum drying at 80 ℃ for 3 h, the sample was quickly transferred to a muffle furnace and calcined at 600 ℃ for 3.5 h. After calcination, the sample was naturally cooled to room temperature to obtain Ox-CNHs nano-conductive particles.

[0091] Weigh 3.0 g of Ox-CNHs nano-conductive particles, 10.0 g of coal gasification fine slag and 5.0 g of tartaric acid, measure 10 mL of isopropanol, add all the above raw materials into a vacuum heating device, set the heating temperature to 100 ℃, heat and stir for 3.5 h, take out the mixture, make up to 1000 mL with deionized water, stir evenly to obtain Ox-CNHs solution;

[0092] Weigh 6.0 g of urea, 6.0 g of aniline (PDMS) and 15.0 g of sodium nitrite and add them to 100 mL of Ox-CNHs solution to obtain a mixed solution. Place the mixed solution in a heating device and heat and stir at 130 °C to dissolve. Then transfer the solution to a hydrothermal reactor and react hydrothermally at 120 °C and a reaction pressure of 4.0 MPa for 3.5 h. After the reaction is completed, allow it to cool naturally to room temperature to obtain a PANI@Ox-CNHs composite solution.

[0093] A 6 cm × 6 cm carbon felt material was used as the working electrode, a platinum sheet (2.5 cm × 2.5 cm) as the counter electrode, and a saturated calomel electrode as the reference electrode. The electrode was installed on an electrochemical workstation. 4.5 g of carbon felt material was added to 50 mL of PANI@Ox-CNHs composite solution. The DC power supply was turned on, and the current was set to 1.5 A in constant current control mode to carry out the electropolymerization reaction. After the reaction was completed, the activated carbon fiber material was removed to obtain the electrode precursor material.

[0094] The electrode precursor material was placed in a microwave drying device and dried for 1.8 h at a microwave power of 1200 W, a temperature of 115 ℃, and an N2 gas flow rate of 12 L / min. After microwave drying, the electrode precursor material was quickly transferred to a freeze-drying device and freeze-dried for 30 min at a power of 1200 W and a temperature of -18 ℃ to obtain an active oxygen electrode material for water purification and disinfection.

[0095] Example 6

[0096] This embodiment is based on embodiments 1-5, using the electrode material described above for water purification and disinfection as the cathode (electrode area 10 cm²). 2 Platinum sheets are commonly used as anodes in the market (electrode area 10 cm²). 2 (Purchased from Tianjin Aida Technology Co., Ltd.) This provides an electrochemical water purification and disinfection device including the aforementioned electrode materials. The structure of the device is shown in the attached document. Figure 6 As shown, the electrochemical water purification and disinfection device includes an electrochemical reactor 6, which has an inlet 1 and an outlet 2. A cathode fixing plate 4 and an anode fixing plate 5 are installed inside the electrochemical reactor 6. The cathode and anode are located between the inlet 1 and the inlet 2 and are perpendicular to the fluid flow direction. The water to be purified and disinfected enters the reactor 6 through the inlet 1. The water flow direction is controlled by flow channel plates 3, and the spacing between the flow channel plates is 5 mm. As a feasible implementation, the electrode fixing assembly is installed inside the electrochemical reactor for easy disassembly and installation.

[0097] In summary, the electrode material prepared by this invention can be used in the field of water purification and disinfection. It can effectively improve the disinfection and purification effect by increasing the production of oxygen-active groups, and can operate efficiently and stably. The electrode material prepared by this invention is simple to operate and can be promoted and applied industrially.

[0098] II. Performance Testing

[0099] The electrode materials prepared in Example 4 and commercially available carbon-based materials (commercially available activated carbon fiber (Comparative 1), commercially available graphite felt (Comparative Example 2), and commercially available carbon felt (Comparative Example 3), purchased from Shanghai Qijie Carbon Co., Ltd.) were subjected to bactericidal performance tests. The initial inoculum concentration of Escherichia coli was 1.0 × 10⁻⁶. 5 CFU / mL - 1.0×10 6 Within the CFU / mL range. The electrode material was immersed in bacterial culture dishes, and the average reduction in the number of regenerating bacteria per milliliter was recorded at 10 min, 20 min, 30 min, and 60 min. Table 1 shows that the electrode material prepared in Example 4 of this invention exhibited an average reduction in the number of regenerating Escherichia coli per milliliter greater than 99.9% within a 60-min immersion time, meeting the requirements and significantly outperforming the commercially available comparative product. The results indicate that the addition of conductive nanoparticles and aniline significantly affects the antibacterial properties of the electrode material.

[0100] Table 1: Antibacterial performance tests of Example 4 and Comparative Examples 1-3

[0101]

[0102] The electrode materials prepared in Example 4 of this invention, along with commercially available activated carbon fibers (Comparative Example 1), commercially available graphite felt (Comparative Example 2), and commercially available carbon felt materials (Comparative Example 3), were used as cathodes (electrode area 10 cm²). 2 Platinum sheets are commonly used as anodes in the market (electrode area 10 cm²). 2 (Purchased from Tianjin Aida Technology Co., Ltd.), with an electrode spacing of 3 cm and a potential of 5 V, electrochemical oxygen-active group bactericidal performance tests were conducted. The initial inoculum concentration was 1.0 × 10⁻⁶. 5 CFU / mL - 1.0×10 6 Within the CFU / mL range, Staphylococcus aureus was used as the inoculum. The electrode material was immersed in the bacterial solution for electrochemical sterilization testing. The average reduction in the number of bacteria recovering growth per milliliter was recorded at 5, 10, 15, and 20 seconds, as shown in Table 2.

[0103] Table 2: Antibacterial performance tests of Example 4 and Comparative Examples 1-3

[0104]

[0105] It can be seen that the electrode material prepared in Example 4 of this invention exhibits significant advantages in the elimination of bacteria in water, with a elimination efficiency far exceeding that of commercially available electrode materials. A 99.9% elimination rate is achieved within an extremely short time of 20 seconds, meeting the requirements. This demonstrates the high efficiency of the electrode material prepared by this invention in water purification and elimination, and it has broad application prospects in the field of water purification and elimination using electrochemical oxygen-active groups.

[0106] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for preparing an active oxygen electrode material for water purification and disinfection, characterized in that, include: S1, Prepare single-walled carbon nanotubes loaded with oxygen-containing functional groups; S2, single-walled carbon nanotube conductive particles loaded with oxygen-containing functional groups, coal gasification slag, tartaric acid, and isopropanol are vacuum stirred to obtain a single-walled carbon nanotube solution loaded with oxygen-containing functional groups. S3, nitrogen source, aniline and reducing agent are added to a solution of single-walled carbon nanotube conductive particles loaded with oxygen-containing functional groups, heated to dissolve, and after hydrothermal reaction, a composite solution of aniline and single-walled carbon nanotubes loaded with oxygen-containing functional groups is obtained. The nitrogen source is any one or a combination of urea or ammonium nitrate, and the reducing agent is any one of sodium nitrite, hydroxylamine hydrochloride, and sodium citrate. S4. Carbon-based materials are added to a composite solution of aniline and single-walled carbon nanotubes loaded with oxygen-containing functional groups, and an electropolymerization reaction is carried out to obtain electrode precursor materials. The carbon-based material is any one of activated carbon fiber, carbon felt graphite felt, carbon paper, and carbon fiber cloth; S5. After sequentially subjecting the electrode precursor material to microwave irradiation and freeze-drying, an active oxygen electrode material for water purification and disinfection is obtained.

2. The method for preparing an active oxygen electrode material for water purification and disinfection according to claim 1, characterized in that, S1 specifically includes: adding single-walled carbon nano-angle material to an acid solution and ultrasonically stirring, then vacuum drying and calcining to obtain single-walled carbon nano-angle conductive particles loaded with oxygen-containing functional groups. The mass ratio of the single-walled carbon nano-angle material to the acid solution is 1~5:5~10, the calcination temperature is 300 ℃~700 ℃, and the calcination time is 1 h~3 h.

3. The method for preparing an active oxygen electrode material for water purification and disinfection according to claim 1, characterized in that, In S2, the mass ratio of the single-walled carbon nanotube conductive particles loaded with oxygen-containing functional groups, coal gasification fine slag, tartaric acid, and isopropanol is 0.2~1:1~10:0.5~5:1~5.

4. The method for preparing an active oxygen electrode material for water purification and disinfection according to claim 1, characterized in that, In S3, the mass ratio of the nitrogen source, aniline, reducing agent, and single-walled carbon nanotube solution loaded with oxygen-containing functional groups is 1~6:1~10:2~5:10~50, the hydrothermal reaction temperature is 80 ℃~150 ℃, the reaction time is 0.5 h~5 h, and the reaction pressure is 2 MPa~6 MPa.

5. The method for preparing an active oxygen electrode material for water purification and disinfection according to claim 1, characterized in that, In S4, the mass ratio of the composite solution of the carbon-based material, aniline, and single-walled carbon nanotubes loaded with oxygen-containing functional groups is 1~10:30~50.

6. The method for preparing an active oxygen electrode material for water purification and disinfection according to claim 1, characterized in that, In S4, the electropolymerization reaction uses the carbon-based material as the working electrode, a platinum sheet as the counter electrode, a DC power supply, constant current control, and a current of 0.1 A to 12 A. The reference electrode is a saturated calomel electrode.

7. The method for preparing an active oxygen electrode material for water purification and disinfection according to claim 1, characterized in that, In S5, the microwave radiation conditions are: 500 W~1500 W, 90 ℃~140 ℃, and N2 gas flow rate of 5 L / min~25 L / min for drying for 0.5 h~6 h; the freeze-drying conditions are: 500 W~1200 W, -20 ℃~-5 ℃ for freeze-drying for 20 min~30 min.

8. An active oxygen electrode material for water purification and disinfection prepared by the preparation method according to any one of claims 1 to 7, characterized in that, The electrode material has a specific surface area of ​​2000 cm². 2 / g~3900 cm 2 / g, hydrophilic angle 60°~80°, porosity 70%~95%, average pore size 0.18 μm~3.6 μm, pore volume 0.20 cm³ / g 3 / g~0.65 cm 3 / g.

9. The application of the active oxygen electrode material for water purification and disinfection as described in claim 8 in the preparation of an electrochemical water purification and disinfection device, characterized in that, The active oxygen electrode material used for water purification and disinfection is used as the cathode.

10. An electrochemical water purification and disinfection device, characterized in that, The device includes an electrochemical reactor (6), which is provided with an inlet (1) and an outlet (2). The electrochemical reactor (6) is provided with a cathode fixing plate (4) and an anode fixing plate (5) for fixing the cathode and the anode. The cathode is made of the active oxygen electrode material for water purification and disinfection as described in claim 8. A flow channel plate (3) is provided between the cathode fixing plate (4) and the anode fixing plate (5) for guiding the flow path of water in the electrochemical reactor.

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