Horizontal penetration type bioelectro-Fenton device and treatment method of wastewater containing organic collecting agent

Abstract

The invention provides a horizontal penetration type bio-electro-Fenton device and a treatment method of wastewater containing an organic collecting agent, and particularly relates to the technical field of water treatment. The horizontal penetration type bioelectro-Fenton device comprises an anode chamber, a reaction chamber and a cathode chamber which are horizontally arranged in sequence; a water inlet is formed in one side, far away from the reaction chamber, of the cathode chamber; a water outlet is formed in one side, away from the reaction chamber, of the anode chamber; a reaction chamber is defined between the cathode chamber and the anode chamber; a cathode plate is arranged in the cathode chamber, is mainly formed by assembling porous carbon felts loaded with a catalyst, and has a porous and water-permeable structure; an anode plate is arranged in the anode chamber and is composed of a carbon felt cultured with pseudomonas and bacillus microorganisms; the horizontal penetration type biological electro-Fenton device further comprises an external circuit, the external circuit is connected with the cathode plate and the anode plate, and the external circuit and the resistor element form a closed loop, so that the device spontaneously generates electricity and drives electro-Fenton reaction under the condition of no external voltage.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, specifically to a horizontally penetrating bioelectric Fenton device and a method for treating wastewater containing organic collectors. Background Technology

[0002] In mineral processing processes such as non-ferrous metal beneficiation and coal flotation, organic mineral collectors, represented by black powder (phosphate esters) and ethyl thiocyanate (dialkyl dithiocarbamate), are widely used. Although these substances possess strong hydrophobicity and selective adsorption capabilities, they enter wastewater along with tailings during production, forming high-concentration, highly toxic, and low-biodegradable organic wastewater. This type of wastewater exhibits significant pollution characteristics: chemical oxygen demand (COD) reaches thousands of mg / L, and it contains stable structures such as aromatic rings, thioether bonds, and heteroatoms, making it difficult to be degraded by conventional microorganisms. Furthermore, it easily causes eutrophication, toxicity accumulation, and ecological risks, posing a serious threat to the environment.

[0003] Current treatment technologies for this type of wastewater have many limitations: physical methods (such as adsorption and membrane separation) can only transfer pollutants and cannot completely degrade them; chemical oxidation methods (such as sodium hypochlorite, ozone, and Fenton's reagent) have problems such as high cost, many byproducts, and strong pH dependence; advanced oxidation processes (AOPs) such as UV / H2O2, electro-Fenton, and photo-Fenton, although they have strong oxidation capabilities, generally have drawbacks such as high energy consumption, complex equipment, and difficult operation and maintenance, making it difficult to meet actual treatment needs.

[0004] In recent years, bioelectro-Fenton (BEF) technology has attracted widespread attention due to its unique advantages of being green, energy-saving, and self-powered. However, existing BEF systems still have significant drawbacks: First, they suffer from high structural resistance, typically employing a dual-chamber structure with a proton exchange membrane isolating the anode and cathode, leading to increased internal resistance, impaired mass transfer, and easy membrane fouling. Second, H2O2 yield is low, with traditional carbon material cathodes exhibiting insufficient catalytic activity and a tendency to undergo four-electron reduction, reducing H2O2 selectivity. Third, anode degradation efficiency is limited, lacking targeted construction of functional microbial communities for specific pollutants, resulting in long system start-up cycles and poor stability. Therefore, there is an urgent need to develop a novel and efficient bioelectro-Fenton system that can overcome the bottlenecks imposed by traditional structures while enhancing the synergistic effect of catalytic performance and biodegradation, thereby achieving low-cost and sustainable treatment of wastewater containing organic mineral collectors.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a horizontally penetrating bioelectric Fenton device and a method for treating wastewater containing organic collectors, aiming to solve at least one of the aforementioned technical problems in the prior art.

[0007] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: A first aspect of the present invention provides a horizontally penetrating bioelectric Fenton device, comprising an anode chamber, a reaction chamber, and a cathode chamber arranged horizontally in sequence; The cathode chamber has an inlet on the side away from the reaction chamber for introducing oxygen-containing organic wastewater; the anode chamber has an outlet on the side away from the reaction chamber for discharging treated effluent. The reaction chamber is formed by the enclosure between the cathode chamber and the anode chamber; The cathode chamber is equipped with a cathode plate, which is mainly assembled from porous carbon felt loaded with catalyst and has a porous and water-permeable structure; the anode chamber is equipped with an anode plate, which is mainly composed of carbon felt cultured with Pseudomonas and Bacillus. The horizontally penetrating bioelectric Fenton device also includes an external circuit, which connects the cathode plate and the anode plate and forms a closed loop with the resistive element, enabling the device to generate electricity spontaneously and drive the electro-Fenton reaction without an external voltage.

[0008] In some embodiments of the present invention, the inlet and / or the outlet are configured as conical or triangular buffer structures to mitigate water flow impact and stabilize the flow pattern.

[0009] In some embodiments of the present invention, the water inlet is provided with an oxygen injection device for pumping oxygen in while water is being introduced, thereby increasing the dissolved oxygen concentration in the device.

[0010] In some embodiments of the present invention, the horizontally penetrating bioelectric Fenton device is further provided with a first sampling port and a second sampling port, the first sampling port being located above the cathode chamber and the second sampling port being located above the anode chamber, for monitoring water quality changes during the reaction process.

[0011] In some embodiments of the present invention, the inlet is further provided with a peristaltic pump for controlling the inlet flow rate and realizing continuous flow operation.

[0012] In some embodiments of the present invention, the water outlet is further provided with a filter screen to intercept solid substances and further purify the water.

[0013] The second aspect of the present invention provides a method for treating wastewater containing organic collectors, which uses the horizontal permeation bioelectric Fenton device described in the first aspect to treat the wastewater containing organic collectors; the wastewater enters the horizontal permeation bioelectric Fenton device through the inlet during the flow process, passes through the cathode chamber into the reaction chamber in sequence, and then passes through the anode chamber and flows out through the outlet to achieve continuous flow operation.

[0014] Furthermore, the organic collector includes at least one of black powder and ethyl thiocyanate.

[0015] Furthermore, the cathode plate is assembled from porous carbon felt supported by a catalyst.

[0016] Preferably, the catalyst is a strip-shaped rod-shaped Mn-C@N.

[0017] Preferably, the doping amount of the catalyst is ≤8%.

[0018] Preferably, the Mn-C@N is mainly obtained by calcining Mn-MOF at high temperature, acid washing, washing and drying.

[0019] Preferably, the high-temperature calcination temperature is 700~900℃ and the time is 2~4h.

[0020] Furthermore, the carbon felt containing microorganisms is made into an anode plate.

[0021] Preferably, the microorganisms include Pseudomonas and Bacillus, which are used to degrade organic collectors to release electrons and participate in bioelectrochemical reactions.

[0022] In some embodiments of the present invention, a method for treating wastewater containing an organic collector includes the following steps: Wastewater containing organic mineral collectors is mixed with oxygen and then introduced into the device through the inlet using a peristaltic pump. The wastewater flows through the cathode chamber and passes through the cathode plate, where it undergoes an oxygen reduction reaction to generate H2O2 and produces hydroxyl radicals for oxidative degradation. The microorganisms in the anode chamber use organic pollutants as a carbon source for metabolism, release electrons, and transfer them to the cathode through an external circuit. The treated wastewater is discharged through the outlet.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects: The horizontally penetrating bioelectric Fenton device provided by this invention employs a horizontally penetrating water flow design, allowing wastewater to enter from the cathode, pass through the reaction chamber, and exit from the anode, achieving continuous flow operation. This effectively reduces system mass transfer resistance and internal resistance, improving reaction efficiency. The cathode chamber efficiently promotes the two-electron oxygen reduction reaction, generating H2O2 in situ, which in turn triggers the bioelectric Fenton reaction, producing a large number of hydroxyl radicals and enhancing oxidative degradation capabilities. Microorganisms at the anode degrade organic matter while generating bioelectricity, driving the cathode reaction and forming a self-powered system. This device requires no external voltage and, through the synergistic effect of anode biodegradation and cathode advanced oxidation, ensures the smooth progress of the bioelectric Fenton reaction.

[0024] The wastewater treatment method containing organic collectors provided by this invention, given the advantages of the above-mentioned device, achieves efficient removal of recalcitrant organic collectors, high COD removal rate, low energy consumption, simple structure, stable operation, and good environmental and economic benefits. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 A schematic diagram of the structure of a horizontally penetrating bioelectric Fenton device provided by the present invention; Figure 2 A schematic diagram of another horizontally penetrating bioelectric Fenton device provided by the present invention; Figure 3 This is a transmission electron microscope image of Mn-MOF; Figure 4 This is a transmission electron microscope (TEM) image of the Mn-C@N catalyst; Figure 5 The degradation curve obtained in Example 1 is shown.

[0027] Explanation of main component symbols: 100-Cathode chamber; 110-Inlet; 120-Cathode plate; 200-Anode chamber; 210-Outlet; 220-Anode plate; 300-Reaction chamber; 400-External circuit; 410-Resistor; 130-First sampling port; 230-Second sampling port; 240-Filter screen. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0029] In the following, the terms “comprising,” “having,” and their cognates, which may be used in various embodiments of the invention, are intended only to indicate a particular feature, number, step, operation, element, component, or combination thereof, and should not be construed as excluding, firstly, the presence of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, or adding the possibility of one or more features, numbers, steps, operations, elements, components, or combinations thereof.

[0030] A first aspect of the present invention provides a horizontally penetrating bioelectric Fenton device, such as Figure 1 As shown, it includes an anode chamber 200, a reaction chamber 300, and a cathode chamber 100 arranged horizontally in sequence; The cathode chamber 100 is provided with an inlet 110 on the side away from the reaction chamber 300 for introducing oxygen-containing organic wastewater; the anode chamber 200 is provided with an outlet 210 on the side away from the reaction chamber 300 for discharging treated effluent. The reaction chamber 300 is formed by enclosing the cathode chamber 100 and the anode chamber 200; The cathode chamber 100 is provided with a cathode plate 120, which is mainly assembled from porous carbon felt loaded with catalyst and has a porous and water-permeable structure; the anode chamber 200 is provided with an anode plate 220, which is mainly composed of carbon felt cultured with Pseudomonas and Bacillus microorganisms. The horizontally penetrating bioelectric Fenton device also includes an external circuit 400, which connects the cathode plate 120 and the anode plate 220 and forms a closed loop with the resistive element 410, so that the device can generate electricity spontaneously and drive the electro-Fenton reaction without external voltage.

[0031] The horizontally penetrating bioelectric Fenton device provided by this invention employs a horizontally penetrating water flow design, allowing wastewater to enter from the cathode, pass through the reaction chamber 300, and exit from the anode, achieving continuous flow operation. This effectively reduces system mass transfer resistance and internal resistance, improving reaction efficiency. The cathode chamber 100 efficiently promotes the two-electron oxygen reduction reaction, generating H2O2 in situ, which in turn triggers the bioelectric Fenton reaction, producing a large number of hydroxyl radicals and enhancing oxidative degradation capabilities. Microorganisms at the anode degrade organic matter while generating bioelectricity, driving the cathode reaction and forming a self-powered system. This device requires no external voltage and, through the synergistic effect of anode biodegradation and cathode advanced oxidation, ensures the smooth progress of the bioelectric Fenton reaction.

[0032] like Figure 1 As shown, the cathode chamber 100 is located at one end of the device, with an inlet 110 on the side away from the intermediate reaction chamber 300 for introducing oxygenated organic wastewater; while the anode chamber 200 is located at the other end, with an outlet 210 on the side away from the reaction chamber 300 for discharging the treated purified water. The cathode chamber 100 and the anode chamber 200 are spatially opposite each other, forming a closed central area, namely the reaction chamber 300, which has no physical diaphragm, allowing water to flow freely while providing ample space for the key oxidation reaction.

[0033] Wastewater enters through the cathode inlet 110 and, under the influence of driving force (such as a peristaltic pump or gravity), flows horizontally through the cathode chamber 100, into the reaction chamber 300, then through the anode chamber 200, and finally out through the anode outlet 210, achieving continuous operation throughout the entire process. This horizontally penetrating flow channel design not only avoids the airlock and dead zone problems that are prone to occur in traditional vertical structures, but also significantly reduces fluid resistance and mass transfer barriers, improving the hydraulic stability and reaction efficiency of the system.

[0034] Regarding the configuration of functional materials, the cathode chamber 100 contains a cathode plate 120, which is assembled from porous carbon felt loaded with catalyst, and typically uses titanium mesh or stainless steel mesh as the conductive substrate. The anode chamber 200 contains an anode plate 220, which is mainly composed of carbon felt loaded with functional microorganisms. These microorganisms have the ability to degrade recalcitrant organic pollutants and can transfer electrons to the carbon fiber electrode during metabolism, forming a stable bioanode. This process not only achieves partial removal of organic matter, but more importantly, it generates spontaneous current, driving the operation of the entire electrochemical system.

[0035] The device also includes a complete external circuit system 400, connecting the cathode plate 120 and the anode plate 220, and connecting a resistor element 410 (such as an adjustable resistor or a load resistor) in series to form a closed loop. Without the need for an external voltage, electrons released by the oxidation of organic matter by the anode microorganisms can be automatically transferred to the cathode via the external circuit 400 to support the generation of H2O2 and subsequent bioelectric Fenton reactions. This synergistic mechanism of microbial electrogeneration combined with advanced cathode oxidation enables the entire system to operate self-powered, with extremely low energy consumption and environmental friendliness.

[0036] In some embodiments of the present invention, the inlet 110 and / or the outlet 210 are configured as conical or triangular buffer structures to mitigate water flow impact and stabilize the flow pattern. Specifically, the buffer structure at the inlet 110 has a gradually expanding geometry, such as a conical flared mouth or a triangular truncated pyramidal guide channel. Its inlet diameter is relatively large, gradually narrowing inward to the outlet size connected to the cathode chamber 100. This allows the high-speed incoming water flow to be smoothly guided into the reaction area, avoiding direct scouring of the cathode plate 120 surface, thereby protecting the structural integrity of the porous catalyst material and the microbial attachment layer. Similarly, the buffer structure at the outlet 210 can reduce the water flow shear force, preventing the biofilm or activated carbon particles in the anode carbon felt from being washed away, while also reducing the formation of eddies and dead zones, and improving the overall flow field uniformity. Such buffer structures are usually integrally molded from inert, corrosion-resistant materials (such as polytetrafluoroethylene, PVC, or plexiglass) and sealed to the reactor shell to ensure hydraulic stability during long-term operation. This design enables the system to maintain a stable flow distribution under continuous flow operation conditions, thereby improving mass transfer efficiency and extending the service life of the device.

[0037] In some embodiments of the present invention, the inlet 110 is equipped with an oxygen injection device to pump oxygen in simultaneously with water intake, thereby increasing the dissolved oxygen concentration within the device. This oxygen injection device may specifically include an external oxygen source (such as an oxygen cylinder or air compressor), a gas flow meter, a shut-off valve, and a gas delivery branch pipe coupled to the water intake pipeline. The end of the gas branch pipe extends into the inlet 110 or merges with the water intake pipeline via a T-junction or Y-junction to form a gas-liquid mixing zone. In actual operation, wastewater containing organic collectors flows in from the inlet end driven by a peristaltic pump, while oxygen is precisely injected into the water flow after being controlled by the flow meter. The turbulent flow helps to achieve uniform dispersion and rapid dissolution of the air bubbles.

[0038] Preferably, the inlet 110 is equipped with a microporous aeration head or a porous metal screen, which can break oxygen into tiny bubbles, increase the gas-liquid contact area, and further improve oxygen mass transfer efficiency. Since the two-electron oxygen reduction reaction at the cathode is a key step in the generation of hydrogen peroxide, its reaction rate is directly limited by the local dissolved oxygen level. Therefore, this integrated oxygen injection design can continuously maintain a high concentration of O2 at the cathode interface, effectively promoting the in-situ generation of H2O2 and thus enhancing the generation of hydroxyl radicals in the subsequent Fenton-like reaction. Furthermore, sufficient dissolved oxygen also benefits the metabolic activity of anolyte functional bacteria (such as Pseudomonas and Bacillus), improving their electron transfer efficiency and the overall power generation performance of the system.

[0039] In some embodiments of the present invention, such as Figure 2As shown, the horizontal penetration bioelectric Fenton device is also provided with a first sampling port 130 and a second sampling port 230. The first sampling port 130 is located above the cathode chamber 100, and the second sampling port 230 is located above the anode chamber 200, for monitoring water quality changes during the reaction process.

[0040] The first sampling port 130 and the second sampling port 230 are used to monitor water quality changes in different functional areas during the reaction process in real time, enabling dynamic evaluation and process optimization of the system's operating status. Specifically, the first sampling port 130 is located above the cathode chamber 100, near the cathode plate 120, and is mainly used to collect effluent or intermediate transition liquid from the cathode side to detect key reaction parameters in this area, such as hydrogen peroxide concentration, dissolved oxygen, pH value, and some primary degradation products of organic matter. The second sampling port 230 is located above the anode chamber 200, above the effluent side of the biodegradable carbon felt, and is used to obtain effluent samples after biodegradation to analyze chemical oxygen demand (COD), total organic carbon (TOC), residual collector concentration (such as black powder), and microbial metabolic activity indicators.

[0041] The two sampling ports are typically made of corrosion-resistant materials (such as PTFE or stainless steel) and are structurally short tubes with screw-sealed caps or shut-off valves. They are normally sealed to prevent leakage and contamination. During sampling, they can be directly connected to a syringe or sampling bottle for non-destructive liquid extraction, making operation simple and not affecting continuous system operation. Preferably, the inner diameter of the sampling ports is designed to be 4-8 mm to avoid clogging due to excessively small orifices while ensuring sufficient fluid throughput. By periodically taking simultaneous samples from the first and second sampling ports 230 and comparing their analysis, the migration and transformation patterns of pollutants in the "electrochemical oxidation-biodegradation" dual pathway can be clearly revealed, reaction bottlenecks can be identified, and H2O2 utilization and mineralization efficiency can be evaluated. This provides a scientific basis for controlling operating parameters such as influent flow rate, oxygen supply, and external resistance load.

[0042] In some embodiments of the present invention, the inlet 110 is further equipped with a peristaltic pump for controlling the inlet flow rate and achieving continuous flow operation. This peristaltic pump is connected to the inlet 110 via a silicone or fluororubber hose. It uses rollers to periodically squeeze the hose, generating negative pressure to draw in liquid and pushes the wastewater into the reactor at a constant rate. Its flow rate is typically adjustable from 0.1 to 10 mL / min (adaptable to the reactor size), ensuring a smooth and uniform flow into the cathode chamber 100. By adjusting the pump's speed or operating mode (e.g., intermittent pulse or continuous operation), the hydraulic residence time (HRT) can be flexibly controlled, thereby optimizing the contact efficiency between pollutants and active substances. This avoids insufficient reaction due to excessively high flow rates or limited mass transfer and biofilm deactivation due to insufficient flow rates. Furthermore, the peristaltic pump has good chemical resistance, is not easily corroded by sulfur-containing, saline, or weakly acidic wastewater, and does not contaminate the fluid, maintaining a pure system environment. Its non-invasive delivery method also avoids the risk of mechanical seal leakage, making it suitable for long-term unattended operation. Combined with the oxygen injection device, the peristaltic pump can also achieve simultaneous gas-liquid input, completing in-situ dissolution of oxygen during the water intake process, further increasing the dissolved oxygen concentration in the cathode area and promoting the efficient generation of H2O2. This design enables the entire horizontal through-type bioelectric Fenton device to break free from the limitations of traditional intermittent operation, possessing the ability to treat continuously discharged industrial wastewater, significantly enhancing the system's practicality, repeatability, and engineering application potential, and is particularly suitable for the on-site continuous treatment of wastewater containing organic collectors in scenarios such as mineral processing and coal flotation.

[0043] In some embodiments of the present invention, such as Figure 2 As shown, the water outlet 210 is also equipped with a filter screen 240 to intercept solid substances and further purify the water.

[0044] The filter screen 240 is typically made of corrosion-resistant and chemically stable materials (such as stainless steel wire mesh, titanium alloy mesh, or polytetrafluoroethylene microporous membrane). It is fixedly installed inside the outlet 210 or in the end-connected pipeline. Its pore size is preferably in the range of 50~200 μm, effectively trapping suspended solids such as detached biofilm fragments, carbon felt fiber debris, or activated carbon particles without causing excessive fluid resistance that could affect normal drainage. The filter screen 240 can be designed with a detachable snap-fit ​​structure or threaded interface for easy periodic cleaning or replacement, preventing pressure drop or poor water flow due to clogging during long-term operation. In actual operation, although the biofilm-laden carbon felt in the anode chamber 200 has good microbial adhesion capabilities, a small amount of biofilm may still peel off under long-term continuous flow scouring or fluctuating reaction conditions. Simultaneously, the activated carbon plates pressed on the cathode side may also generate fine particles due to physical compression or vibration. If these solid impurities are discharged with the effluent, they not only affect the clarity of the effluent but may also interfere with subsequent monitoring equipment. By installing this filter screen 240, terminal solid-liquid separation can be achieved without adding additional treatment units, ensuring the stability of the effluent and the accuracy of the test data. Furthermore, the presence of the filter screen 240 also provides intuitive feedback for system maintenance—when significant dirt accumulation is observed on the screen surface, it prompts for a shutdown inspection or biofilm regeneration operation.

[0045] The second aspect of the present invention provides a method for treating wastewater containing organic collectors, which uses the horizontal permeation bioelectric Fenton device described in the first aspect to treat the wastewater containing organic collectors; the wastewater enters the horizontal permeation bioelectric Fenton device through the inlet 110 during the flow process, passes through the cathode chamber 100 in sequence to enter the reaction chamber 300, and then passes through the anode chamber 200 to flow out through the outlet 210, thereby achieving continuous flow operation.

[0046] The wastewater treatment method containing organic collectors provided by this invention, given the advantages of the above-mentioned device, achieves efficient removal of recalcitrant organic collectors, high COD removal rate, low energy consumption, simple structure, stable operation, and good environmental and economic benefits.

[0047] Furthermore, the organic collector includes at least one of black powder and ethyl thiocyanate.

[0048] Furthermore, activated carbon doped with catalyst is pressed into a cathode plate 120.

[0049] Preferably, the catalyst is Mn-C@N, prepared from Mn-MOF precursor through high-temperature calcination, acid washing, washing, and drying, and is rich in uniformly distributed Mn-N. x With multiple active sites, it can efficiently catalyze the two-electron oxygen reduction reaction of oxygen, selectively generating hydrogen peroxide and avoiding excessive reduction to water, thereby significantly improving the yield and utilization efficiency of H2O2.

[0050] Preferably, the doping amount of the catalyst is ≤8%.

[0051] Preferably, the Mn-C@N is mainly obtained from Mn-MOF through high-temperature calcination, acid washing, washing, and drying. Under an inert atmosphere (such as nitrogen or argon), as the temperature rises to 700-900℃, the organic ligands of Mn-MOF undergo pyrolytic carbonization, generating a nitrogen-doped porous carbon matrix. Simultaneously, metallic manganese ions are reduced in situ to elemental manganese or low-valence manganese oxide nanoparticles, which are uniformly embedded in the carbon framework. Subsequently, the unstable metal particles are dissolved by an acid washing step, leaving behind Mn-N with high catalytic activity. x The coordination structure and numerous mesoporous channels ultimately form a composite material—Mn-C@N—with nitrogen-doped carbon coating manganese-based active centers. This process not only preserves the original high specific surface area and regular pore structure of MOF materials, but also constructs a large number of highly efficient oxygen reduction reaction (ORR) active sites, especially the Mn-N4 sites that are conducive to the selective generation of H2O2 via the two-electron pathway, thereby significantly improving its ability and stability to catalyze O2 reduction in bioelectric Fenton systems.

[0052] Preferably, the high-temperature calcination temperature is 700~900℃ and the time is 2~4 hours.

[0053] Typical, but not limiting, the calcination temperature can be, for example, 700°C, 750°C, 800°C, 850°C, or 900°C, or any value within the range of 700°C to 900°C; the time can be, for example, 2h, 3h, or 4h, or any value within the range of 2h to 4h.

[0054] Furthermore, the carbon felt containing microorganisms is made into an anode plate 220.

[0055] Preferably, the microorganisms include *Pseudomonas* and *Bacillus*, which are used to degrade organic collectors to release electrons and participate in bioelectrochemical reactions. Both *Pseudomonas* and *Bacillus* are functional bacterial groups with strong metabolic activity and environmental adaptability, playing a key role in the bioelectro-Fenton system of this invention. *Pseudomonas* possesses highly efficient aromatic compound degradation capabilities, able to recognize and break thioether bonds, dithio groups, and benzene ring structures in organic collectors (such as black powder), gradually converting them into small-molecule organic acids or intermediate metabolites; while *Bacillus* is known for its strong resistance to toxicity, salt and alkali tolerance, and spore-forming ability, enabling it to survive stably in high-concentration toxic wastewater environments and participate in the oxidation and desulfurization processes of sulfur-containing pollutants. More importantly, both types of microorganisms possess excellent extracellular electron transport capabilities. They can efficiently transfer electrons released during the degradation of organic matter to the surface of the anode carbon felt through direct contact, electron shuttles (or membrane-bound redox proteins), forming a stable bio-electrode interface current. These electrons spontaneously flow to the cathode via the external circuit 400, driving the oxygen reduction reaction to generate H2O2, thereby triggering the bioelectric Fenton effect and achieving a closed-loop coupling of pollutant degradation, electricity generation, and advanced oxidation. By enriching and colonizing this composite functional microbial community on the carbon felt carrier, not only is the removal efficiency of the anode for recalcitrant organic collectors significantly improved, but the system's start-up speed, operational stability, and long-term resistance to shock loads are also enhanced, forming the core biological basis for achieving self-powered and sustainable water treatment.

[0056] In some embodiments of the present invention, a method for treating wastewater containing an organic collector includes the following steps: Wastewater containing organic mineral collectors is mixed with oxygen and then introduced into the device through inlet 110 via a peristaltic pump. The wastewater flows through cathode chamber 100 where it undergoes an oxygen reduction reaction to generate H2O2 and produces hydroxyl radicals for oxidative degradation. The microorganisms in the anode chamber 200 utilize organic pollutants as a carbon source for metabolism, release electrons, and transfer them to the cathode through the external circuit 400; The wastewater continues to flow through the anode chamber 200, where residual pollutants are further degraded by microorganisms, and the treated wastewater is discharged through the outlet 210.

[0057] The present invention is further illustrated below with specific embodiments and comparative examples. However, it should be understood that these embodiments are merely for illustrative purposes and should not be construed as limiting the invention in any way. Unless otherwise specified, the raw materials used in the embodiments and comparative examples of the present invention were carried out under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0058] The Mn-C@N catalyst used in this invention was prepared according to the following steps: manganese acetate and 2-methylimidazole were weighed and dissolved in methanol, stirred for 24 hours, centrifuged to collect the precipitate, washed and dried to obtain a rod-shaped Mn-MOF precursor. Transmission electron microscopy was performed on the Mn-MOF, and the results are as follows: Figure 3 As shown in the figure. Mn-MOF was placed in a tube furnace and heated to 800℃ at a rate of 5℃ / min under a nitrogen atmosphere, held at that temperature for 2 hours, cooled, and then washed with dilute nitric acid to remove unstable components. After repeated washing with deionized water and drying at 60℃, a black powder was obtained, which is the Mn-C@N catalyst. The corresponding transmission electron microscopy (TEM) image is shown in the figure. Figure 4 As shown.

[0059] Figure 3 The image is a transmission electron microscope image of Mn-MOF, showing that it has a well-defined rod-shaped morphology with a size in the nanometer range (scale bar 100 nm). The rod-shaped structure is regular and well-dispersed. Figure 4 This is a transmission electron microscope image of the Mn-C@N catalyst. It can be seen that it still retains the basic rod-shaped morphology, but compared with the precursor, there are certain structural changes, and the details and dispersion state of the rod-shaped structure are different.

[0060] In summary, the Mn-MOF precursor exhibits a regular nanorod-like structure, and the Mn-C@N catalyst obtained after high-temperature calcination and acid washing still maintains the rod-like morphology, indicating that the basic morphology was preserved during the preparation process.

[0061] Example 1 This embodiment provides a method for treating wastewater containing organic collectors, the specific process of which is as follows: 1. Cut commercially available porous carbon felt into 3cm circles. Place the carbon felt in a methanol solution containing Mn-C@N catalyst and repeatedly turn it over. After 10 minutes, remove the carbon felt and place it in a tube furnace for calcination. Under a nitrogen atmosphere, heat the carbon felt to 800℃ at a rate of 5℃ / min and hold for 1 hour. After natural cooling, carefully insert a titanium mesh into the carbon felt to obtain cathode plate 120.

[0062] 2. Cut commercially available carbon felt to a suitable size and immerse it in a nutrient solution containing NH4Cl, KH2PO4, NaCl, MgSO4, and CaCl2. Inoculate it with a mixed bacterial strain derived from activated sludge from mine wastewater and culture it at 30℃ under alternating anaerobic and microaerobic conditions for 20 days. Use the carbon felt colonized with microorganisms as the anode plate 220, embedding one end of a titanium wire inside the carbon felt and connecting the other end to the external circuit 400.

[0063] 3. For example Figure 2As shown, the cathode plate 120 and anode plate 220 are installed parallel to each other on both sides of the reactor, leaving a reaction chamber 300 in the middle. The inlet 110 is connected to a peristaltic pump and an oxygen cylinder. The outlet 210 is equipped with a filter screen 240. The external circuit 400 is connected to the anode and cathode via wires and connected in series with a light-emitting diode (LED) as an indicator of power generation signal.

[0064] 4. Prepare simulated wastewater containing 100 mg / L butylamine black powder. Turn on the peristaltic pump and control the flow rate at 2 mL / min, while simultaneously introducing oxygen (0.5 L / min). The wastewater flows in from inlet 110, passes through the cathode layer, reaction chamber 300, and anode layer in sequence, and is then discharged.

[0065] 5. Samples were taken from the first sampling port 130 and the second sampling port 230 at the 0th, 15th, 25th, 50th, 60th, and 80th hours of operation, respectively; the concentration of butylamine black powder was measured, the degradation rate was calculated, and the degradation curve was plotted, as shown below. Figure 5 As shown.

[0066] The results showed that the concentration of butylamine black powder continuously decreased with increasing reaction time, and the degradation rate reached 82.3% within 80 hours, indicating that the system has excellent pollutant removal capabilities. Simultaneously, stable LED illumination was observed, proving that the system successfully achieved microbial electro-Fenton process-driven electro-electricity.

[0067] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A horizontal penetration type bio-electro-Fenton device, characterized in that, The horizontal penetration type bio-electro-Fenton device comprises an anode chamber, a reaction chamber and a cathode chamber arranged in sequence in the horizontal direction. The cathode chamber is provided with a water inlet on the side away from the reaction chamber for introducing oxygen-containing organic wastewater, and the anode chamber is provided with a water outlet on the side away from the reaction chamber for discharging treated effluent. The reaction chamber is formed between the cathode chamber and the anode chamber. The cathode chamber is provided with a cathode electrode plate mainly composed of a porous carbon felt loaded with a catalyst, which has a porous and water-permeable structure. The anode chamber is provided with an anode electrode plate mainly composed of a carbon felt cultured with Pseudomonas and Bacillus microorganisms.

2. The horizontal penetrating bio-electro-Fenton device according to claim 1, wherein, The horizontal penetration type bio-electro-Fenton device further comprises an external circuit connected between the cathode electrode plate and the anode electrode plate and a resistor element to form a closed loop, so that the device can generate electricity and drive the electro-Fenton reaction spontaneously without an external voltage. The water inlet and / or the water outlet are provided in a conical or triangular buffer structure to slow down the water flow impact and stabilize the flow state.

3. The horizontal penetrating bio-electro-Fenton device according to claim 1, wherein, Preferably, the water inlet is provided with an oxygen injection device for pumping oxygen while introducing water to increase the dissolved oxygen concentration in the device.

4. The horizontal penetrating bio-electro-Fenton device according to any one of claims 1-3, characterized in that, A first sampling port is provided above the cathode chamber, and a second sampling port is provided above the anode chamber for monitoring the water quality change during the reaction process.

5. The horizontal penetrating bio-electro-Fenton device according to any one of claims 1-3, wherein, The water inlet is further provided with a peristaltic pump for controlling the water inflow to realize continuous flow operation.

6. A method for treating wastewater containing an organic collector, characterized by, The water outlet is further provided with a filter screen for intercepting solid substances to further purify the effluent. The horizontal penetration type bio-electro-Fenton device according to any one of claims 1-5 is used to treat wastewater containing organic collectors.

7. The treatment method according to claim 6, characterized in that, The wastewater flows through the water inlet into the horizontal penetration type bio-electro-Fenton device, penetrates the cathode chamber into the reaction chamber, and then penetrates the anode chamber to flow out through the water outlet, realizing continuous flow operation.

8. The treatment method of claim 6, wherein The organic collector includes at least one of sodium cyanide and ethylthiuram. The cathode electrode plate is assembled from a porous carbon felt loaded with a catalyst. Preferably, the catalyst is a strip-shaped Mn-C@N. Preferably, the doping amount of the catalyst is ≤8%. Preferably, the Mn-C@N is obtained by high-temperature calcination, acid pickling, washing and drying of Mn-MOF.

9. The processing method according to claim 6, wherein Preferably, the high-temperature calcination is performed at a temperature of 700-900°C for 2-4h. The carbon felt loaded with microorganisms is made into an anode electrode plate.

10. The treatment method according to any one of claims 6 to 9, characterized in that, Preferably, the microorganisms include Pseudomonas and Bacillus for degrading organic collectors to release electrons and participate in bio-electrochemical reactions. The method comprises the following steps: The wastewater containing organic mineral collectors is mixed with oxygen and introduced into the device through the water inlet by a peristaltic pump. The wastewater penetrates the cathode electrode plate in the cathode chamber to generate H2O2 through an oxygen reduction reaction and produce hydroxyl radicals for oxidative degradation. The microorganisms in the anode chamber metabolize organic pollutants as carbon sources to release electrons and transmit them to the cathode through an external circuit. The treated wastewater is discharged through the water outlet.

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