Electrocatalytic reduction-oxidation reaction device and application thereof

Abstract

The application belongs to the field of organic wastewater degradation, and particularly relates to an electro-catalytic reduction-oxidation reaction device and application thereof. The device comprises a reactor (4), a power supply (12), a peristaltic pump (3), a water inlet pool (1) and a water outlet pool (11), and is characterized in that the reactor (4) is divided into a cathode chamber and an anode chamber by a proton exchange membrane; the anode chamber comprises a graphite sheet (9) and a Sn-Sb-Ag modified three-dimensional ceramic particle electrode (8), and the cathode chamber comprises a titanium sheet (5) and a Pd-In modified three-dimensional ceramic particle electrode (6). In the use process, the total / multi-halogenated organic matter in water first undergoes a reduction reaction to remove halogen in the cathode chamber, and then enters the anode chamber to undergo an oxidation reaction for degradation, which is conducive to realizing safe and efficient synergistic mineralization of total / multi-halogenated organic matter.

Description

Technical Field

[0001] This invention belongs to the field of organic wastewater degradation, specifically relating to an electrocatalytic reduction-oxidation reaction device and its application. Background Technology

[0002] Full- and polyhalogenated organic compounds (PHOCs) are widely found in pesticides, wood preservatives, herbicides, disinfectants, personal care formulations, dye intermediates, and other chemical products. Due to the biotoxicity of the halogen atoms (X = F, Cl, Br, I) in their molecules, large amounts of halogenated pollutants remaining in water, air, soil, and even biological substrates not only endanger environmental and ecological safety but can also threaten human health through the food chain. Examples include perfluorooctanoic acid (PFOA), polychlorinated biphenyls (PCBs), and dichlorodiphenyltrichloroethane (DDTs). Because halogen atoms are electron-withdrawing groups and have a high number of substitutions, these substances have low highest occupied molecular orbital energies, making it difficult to break the CX bonds using conventional physical or biological methods. Furthermore, conventional oxidation methods may generate even more toxic degradation intermediates.

[0003] Electrocatalytic reduction hydrodehalogenation is a process that utilizes an electroreduction reaction to generate atomic hydrogen (H₂). The technology of dehalogenating and detoxifying halogenated organic compounds is widely used due to its advantages such as high selectivity, simple operation, and environmental friendliness. Atomic hydrogen (H) () is a highly reducing active group with a redox potential of -2.1V. vs. RHE (Reduced Hexavalent Iron) selectively breaks CX bonds. Compared to other dehalogenation technologies such as zero-valent iron (ZVI) and bioreduction, its reaction conditions are mild and do not generate secondary waste. However, as the number of halogen atoms decreases, the dehalogenated products are difficult to further reduce, and their toxicity is even higher than that of the parent pollutants. Compared to fully / polyhalogenated organic compounds, low-halogenated organic compounds are more prone to oxidative degradation. Therefore, this invention designs a flow-through electrocatalytic reduction-oxidation relay degradation system based on a three-dimensional particle electrode. That is, fully / polyhalogenated organic pollutants are first reduced to low-halogenated products using a reduction method, and then these intermediate products are degraded using an oxidation method, thereby achieving deep dehalogenation and mineralization.

[0004] This flow-through electrocatalytic reduction-oxidation relay degradation system based on three-dimensional particle electrodes allows wastewater to flow within a space filled with these electrodes. This reduces the thickness of the diffusion layer on the electrode surface, overcoming the mass transfer limitations of traditional flat-plate electrocatalytic systems and significantly improving the interphase mass transfer rate of pollutants. The continuous flow reactor is divided into a cathode chamber and an anode chamber by a proton exchange membrane. The particle electrodes in the cathode chamber are cathode particles, and those in the anode chamber are anode particles, making it suitable for treating wastewater with low conductivity. Under the influence of an electric field, the particle electrodes at both the cathode and anode become charged, thus greatly increasing the surface area of ​​the main electrodes within a limited space and promoting pollutant degradation. Each electrode chamber has an inlet and an outlet, and the influent flow rate is controlled by a peristaltic pump. Wastewater first undergoes a reduction reaction in the cathode chamber and then enters the anode chamber for oxidation, ultimately achieving complete mineralization and degradation.

[0005] Chinese invention patent application CN202210717325.6 discloses a method for treating halogenated organic wastewater using an advanced reduction-oxidation coupling system based on semi-dry flue gas desulfurization ash. This system utilizes the coupling of ultraviolet light and sulfite to generate a strongly reducing active substance for the reduction and dehalogenation of halogenated organic compounds. After the dehalogenation stage, a certain amount of desulfurization ash, nano-transition metal oxide catalyst, and dissolved oxygen are added in situ, and the pH is adjusted. Then, under ultraviolet light, a strong oxidizing substance is generated for oxidative degradation. While this reduction-oxidation coupling system can effectively remove halogenated organic compounds, it suffers from problems such as high energy consumption, difficulty in recovering the added catalyst, and a large reactor footprint.

[0006] Therefore, there is a need to develop an electrocatalytic reduction-oxidation reaction device that has low energy consumption, small footprint, and can achieve safe, efficient, and synergistic mineralization of fully / multi-halogenated organic compounds. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides an electrocatalytic reduction-oxidation reactor and its application. This invention constructs a flow-through electrocatalytic reduction-oxidation relay degradation system based on a three-dimensional particle electrode. The reactor in this system is divided into a cathode chamber and an anode chamber by a proton exchange membrane. Wastewater flows within a space filled with the three-dimensional particle electrode. All / polyhalogenated organic compounds in the water first undergo reduction and dehalogenation in the cathode chamber, and then enter the anode chamber for oxidation and degradation. This facilitates the safe, efficient, and synergistic mineralization of all / polyhalogenated organic compounds.

[0008] To achieve the above-mentioned objectives of this invention, the specific technical solution adopted by this invention is as follows:

[0009] The present invention provides an electrocatalytic reduction-oxidation reaction device, comprising a reactor (4), a power supply (12), a peristaltic pump (3), an inlet pool (1) and an outlet pool (11). The reactor (4) is divided into a cathode chamber and an anode chamber by a proton exchange membrane. The anode chamber comprises a graphite sheet (9) and a Sn-Sb-Ag modified three-dimensional ceramic particle electrode (8). The cathode chamber comprises a titanium sheet (5) and a Pd-In modified three-dimensional ceramic particle electrode (6).

[0010] Preferably, both the cathode chamber and the anode chamber are provided with an inlet and an outlet; the inlet pool (1) and the peristaltic pump (3) are connected to the inlet of the cathode chamber through the inlet pipe (2), the outlet pool (11) is connected to the outlet of the anode chamber through the outlet pipe (10), and the outlet of the cathode chamber is connected to the inlet of the anode chamber; the positive and negative terminals of the power supply (12) are connected to the anode and cathode of the reactor (4) through wires, respectively.

[0011] Preferably, the anode is a graphite sheet (9), the cathode is a titanium sheet (5), the cathode and the anode are located on both sides of the reactor, and are separated by a Sn-Sb-Ag modified three-dimensional ceramic particle electrode (8), a Pd-In modified three-dimensional ceramic particle electrode (6) and a proton exchange membrane.

[0012] Preferably, both the cathode chamber and the anode chamber are "serpentine" spaces; the Sn-Sb-Ag modified three-dimensional ceramic particle electrode (8) and the Pd-In modified three-dimensional ceramic particle electrode (6) are placed in the "serpentine" spaces of the anode chamber and the cathode chamber, respectively.

[0013] Preferably, the thickness of the proton exchange membrane is 0.4-0.5 mm.

[0014] Preferably, the preparation method of the Sn-Sb-Ag modified three-dimensional ceramic particle electrode (6) includes:

[0015] S1: Ceramic microparticles are etched in boiling hydrochloric acid and then washed with water to obtain pretreated ceramic microparticles;

[0016] S2: The pretreated ceramic particles are soaked in AgNO3 aqueous solution, dried, and calcined;

[0017] S3: Take the ceramic particles treated by S2, soak them in an ethanol solution containing SnCl4 and SbCl3, dry them, and calcine them;

[0018] S4: Repeat steps S2 and S3 alternately 3-6 times to obtain the result.

[0019] More preferably, the ceramic microparticles in step S1 are spherical alumina ceramic particles with an open pore structure; the spherical alumina ceramic particles, by mass percentage, comprise 70-75% SiO2, 20-25% Al2O3, 2-4% K2O, and 0.5-1.5% Fe2O3; the particle size of the spherical alumina ceramic particles is 2.5-4.0 mm, and the density is 1.6-2.0 g / cm³. -3 The pore volume is 0.1-0.15 cm³. 3 / g.

[0020] More preferably, the hydrochloric acid in step S1 has a mass fraction of 12-24%, the etching time is 20-40 min, the water washing is ultrasonic water washing, the water washing time is 5-15 min, and the number of water washings is 2-3 times.

[0021] More preferably, in step S2, the concentration of the AgNO3 aqueous solution is 0.02-0.05 M, the soaking time is 0.3-0.6 h, the drying temperature is 100-110℃, and the drying time is 8-15 min; the calcination temperature is 400-500℃, and the calcination time is 0.5-1.5 h.

[0022] More preferably, in step S3, the concentrations of SnCl4 and SbCl3 are 0.25-0.35 M and 0.02-0.03 M, respectively; the soaking time is 0.3-0.6 h; and the drying temperature is 100-110 °C. ℃ The drying time is 8-15 minutes; the calcination temperature is 400-500℃ and the calcination time is 0.5-1.5 hours.

[0023] Preferably, the preparation method of the Pd-In modified three-dimensional ceramic particle electrode (8) includes:

[0024] (1) The pretreated ceramic particles were immersed in a mixed solution of PdCl2 and InCl3·4H2O, sonicated, allowed to stand, dried, and calcined.

[0025] (2) Repeat step (1) 2-4 times, then reduce in an H2 atmosphere to obtain the product.

[0026] More preferably, the solvent of the mixed solution in step (1) is a 0.05-0.15M HCl solution; the concentrations of PdCl2 and InCl3 in the mixed solution are both 0.25-0.35 M; the molar ratio of Pb:In in the mixed solution is 1:0.5-2; the ultrasonication time is 5-8 h, the standing time is 20-30 h; the drying temperature is 100-130℃, the calcination temperature is 280-320℃, and the calcination time is 100-130 min.

[0027] More preferably, the reduction temperature in step (2) is 180-220℃, the reduction time is 4-6 h, and the flow rate of H2 is 80-120 mL / min.

[0028] This invention also relates to the application of the above-mentioned electrocatalytic reduction-oxidation reaction device in the degradation of all-halogenated or polyhalogenated organic compounds in water.

[0029] Preferably, the concentration of the halogenated organic compound is 0.5-10.0 mg / L.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) This invention provides a reaction device for electrocatalytic reduction-oxidation of all / multi-halogenated organic compounds in water. Wastewater flows in a space filled with three-dimensional ceramic particle electrodes. Since the particle electrodes have a microporous structure, it is beneficial to compress the thickness of the diffusion layer on the electrode surface to improve the mass transfer efficiency of the system and greatly improve the removal efficiency of pollutants.

[0032] (2) The continuous flow reactor is divided into a cathode chamber and an anode chamber by a proton exchange membrane. The particle electrode in the cathode chamber is in contact with the cathode to form a single cathode three-dimensional electrode, and the particle electrode in the anode chamber is in contact with the anode to form a single cathode three-dimensional electrode. This can greatly increase the effective area of ​​the electrode, and the system can be used to treat wastewater with low conductivity.

[0033] (3) The cathode chamber and anode chamber are designed as a “serpentine” space, which ensures the water flux per unit area (usually the larger the water flux per unit area, the higher the mass transfer efficiency of pollutants on the electrode surface), effectively increases the hydraulic residence time of wastewater in the chamber, and has the characteristics of small footprint.

[0034] (4) The electrocatalytic reduction-oxidation relay degradation system constructed in this invention enables fully / polyhalogenated organic compounds to undergo reduction defluorination and oxidation degradation reactions in sequence, which is beneficial to the deep / complete dehalogenation and mineralization of fully / polyhalogenated organic compounds. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the reaction apparatus in Embodiment 1 of the present invention;

[0036] Figure 2 This is a schematic diagram of the reactor composition in Embodiment 1 of the present invention;

[0037] Figure 3 This is a schematic diagram of the cross-section of the cathode chamber in Embodiment 1 of the present invention, with the arrows indicating the direction of water flow;

[0038] Reference numerals: 1. Inlet pool; 2. Inlet pipe; 3. Inlet pump; 4. Reactor; 5. Titanium sheet; 6. Pd-In modified three-dimensional ceramic particle electrode; 7. Proton exchange membrane; 8. Sn-Sb-Ag modified three-dimensional ceramic particle electrode; 9. Graphite sheet; 10. Outlet pipe; 11. Outlet pool; 12. Power supply. Detailed Implementation

[0039] The technical solutions in the embodiments of the present invention will be further described in detail below. The described embodiments are only a part of the present invention and are used to explain the present invention, but are not intended to limit the present invention. Therefore, other embodiments obtained by other people skilled in the art without creative labor are all within the protection scope of the present invention.

[0040] Spherical alumina ceramic particles, purchased from Pingxiang Jinfeng Chemical Packing Co., Ltd., model number DA.

[0041] The raw materials used in the embodiments of this invention are all industrial products and are commercially available.

[0042] Example 1

[0043] An electrocatalytic reduction-oxidation reaction device, such as Figure 1 As shown, it includes: 1. Inlet pool; 2. Inlet pipe; 3. Inlet pump; 4. Reactor; 5. Titanium sheet; 6. Pd-In three-dimensional ceramic particle electrode; 7. Proton exchange membrane; 8. Sn-Sb-Ag modified three-dimensional ceramic particle electrode; 9. Graphite sheet; 10. Outlet pipe; 11. Outlet pool; 12. Power supply.

[0044] The preparation method of Sn-Sb-Ag modified three-dimensional ceramic particle electrode is as follows:

[0045] S1: Ceramic microparticles were etched in boiling 15% hydrochloric acid for 35 minutes. The etched microparticles were then ultrasonically cleaned in distilled water for 10 minutes, and the cleaning was repeated twice.

[0046] S2: Soak these pretreated ceramic particles in an aqueous solution containing 0.035 M AgNO3 for 0.4 h, dry them at 105 °C for 12 min, and then calcine them at 460 °C for 1.0 h.

[0047] S3: Then, using ethanol as a solvent, it was soaked in a solution containing 0.35 M SnCl4 and 0.025 M SbCl3 for 0.5 h, dried at 105 °C for 10 min, and then calcined at 460 °C for 1.0 h.

[0048] S4: Repeat steps S1 and S2 alternately 5 times to obtain a three-dimensional ceramic particle electrode modified with Sn-Sb-Ag.

[0049] The preparation method of Pd-In modified three-dimensional ceramic particle electrodes is as follows:

[0050] (1) Take the pretreated ceramic particles from S1;

[0051] (2) Prepare a mixed solution of 0.03M PdCl2 and 0.03M InCl3·4H2O using 0.1M HCl solution. The molar ratio of Pb:In in the mixed solution is 1:1. Then, immerse the pretreated ceramic particles in the solution, sonicate for 7 h, and let stand for 24 h.

[0052] (3) Then the ceramic particles after standing are dried at 120°C and then placed in a muffle furnace at 300°C for 120 min.

[0053] (4) After repeating steps (2) and (3) three times alternately, the active ceramic particles are reduced in H2 atmosphere (200℃; flow rate 100 mL / min) for 5 h to obtain Pd-In modified three-dimensional ceramic particle electrode.

[0054] according to Figure 1 The schematic diagram of the reaction device shows that the inlet tank (1) and the peristaltic pump (3) are connected to the inlet of the cathode chamber through the inlet pipe (2), the outlet tank (11) is connected to the outlet of the anode chamber through the outlet pipe (10), and the outlet of the cathode chamber is connected to the inlet of the anode chamber. The positive and negative terminals of the power supply (12) are connected to the anode and cathode of the reactor (4) through wires, respectively. By assembling the various devices, an electrocatalytic reduction-oxidation reaction device is obtained.

[0055] Example 2

[0056] An electrocatalytic reduction-oxidation reaction device, such as Figure 1 As shown.

[0057] The preparation method of Sn-Sb-Ag modified three-dimensional ceramic particle electrode is as follows:

[0058] S1: Ceramic microparticles were etched in boiling 12% hydrochloric acid for 40 min. The etched microparticles were then ultrasonically cleaned in distilled water for 5 min. The cleaning was repeated 3 times to obtain pretreated ceramic microparticles.

[0059] S2: These pretreated ceramic particles were soaked in an aqueous solution containing 0.02M AgNO3 for 0.6 h, dried at 100 °C for 15 min, and then... ℃ Calcination for 1.5 hours under the specified conditions;

[0060] S3: Then, using ethanol as a solvent, soak in a solution containing 0.25 M SnCl4 and 0.02 M SbCl3 for 0.6 h, dry at 100 °C for 15 min, and then at 400 °C. ℃ Calcination for 1.5 hours under the specified conditions;

[0061] S4: Repeat steps S1 and S2 alternately 6 times to obtain a three-dimensional ceramic particle electrode modified with Sn-Sb-Ag.

[0062] The preparation method of Pd-In modified three-dimensional ceramic particle electrodes is as follows:

[0063] (1) Take the pretreated ceramic particles from S1;

[0064] (2) Prepare a mixed solution of 0.035M PdCl2 and 0.02M InCl3·4H2O using 0.05 M HCl solution. Then, immerse the pretreated ceramic particles in the solution, sonicate for 8 hours, and let stand for 30 hours.

[0065] (3) Then the ceramic particles after standing are dried at 100°C and then placed in a muffle furnace at 280°C for 130 min.

[0066] (4) After repeating steps (2) and (3) 4 times alternately, the active ceramic particles were reduced in an H2 atmosphere (180℃; flow rate 80 mL / min) for 6 h to obtain a Pd-In modified three-dimensional ceramic particle electrode.

[0067] The electrocatalytic reduction-oxidation reaction apparatus is assembled in the same way as in Example 1.

[0068] Example 3

[0069] An electrocatalytic reduction-oxidation reaction device, such as Figure 1 As shown.

[0070] The preparation method of Sn-Sb-Ag modified three-dimensional ceramic particle electrode is as follows:

[0071] S1: Ceramic microparticles were etched in boiling 24% hydrochloric acid for 20 min, and the etched microparticles were ultrasonically cleaned in distilled water for 15 min, and the cleaning was repeated twice.

[0072] S2: These pretreated ceramic particles were soaked in an aqueous solution containing 0.05 M AgNO3 for 0.3 h, dried at 110 °C for 8 min, and then calcined at 500 °C for 0.5 h.

[0073] S3: Then, using ethanol as a solvent, it was soaked in a solution containing 0.35 M SnCl4 and 0.03 M SbCl3 for 0.3 h, dried at 110 °C for 8 min, and then calcined at 500 °C for 0.5 h.

[0074] S4: Repeat steps S1 and S2 alternately 4 times to obtain a three-dimensional ceramic particle electrode modified with Sn-Sb-Ag.

[0075] The preparation method of Pd-In modified three-dimensional ceramic particle electrodes is as follows:

[0076] (1) Take the pretreated ceramic particles from S1;

[0077] (2) Prepare a mixed solution of 0.02 M PdCl2 and 0.035 M InCl3·4H2O using 0.15 M HCl solution. The molar ratio of Pb:In in the mixed solution is 1:2. Then, immerse the pretreated ceramic particles in the solution, sonicate for 5 h, and let stand for 20 h.

[0078] (3) Then the ceramic particles after standing are dried at 130°C and then placed in a muffle furnace at 320°C for 100 min.

[0079] (4) After repeating steps (2) and (3) twice, the active ceramic particles were reduced in an H2 atmosphere (220℃; flow rate 1200 mL / min) for 4 h to obtain a Pd-In modified three-dimensional ceramic particle electrode.

[0080] The electrocatalytic reduction-oxidation reaction apparatus is assembled in the same way as in Example 1.

[0081] Comparative Example 1

[0082] An electrocatalytic reduction-oxidation reaction device is prepared in the same way as in Example 1, except that: 8. The Sn-Sb-Ag modified three-dimensional ceramic particle electrode is replaced with a Sn-Sb-Cu modified three-dimensional ceramic particle electrode.

[0083] In Example 1, the 0.035 M AgNO3 aqueous solution in step S2 was replaced with a 0.035 M CuNO3 aqueous solution, and the other preparation processes were the same as in Example 1.

[0084] Comparative Example 2

[0085] An electrocatalytic reduction-oxidation reaction device is prepared using the same method as in Example 1, except that: 6. The Pd-In modified three-dimensional ceramic particle electrode is replaced with a Pd modified three-dimensional ceramic particle electrode. The specific preparation process is as follows:

[0086] Pd-modified three-dimensional ceramic particle electrode:

[0087] (1) Take the pretreated ceramic particles from S1;

[0088] (2) Prepare a PdCl2 solution with a molar concentration of 0.06 M using 0.1 M HCl solution. Then, immerse the pretreated ceramic particles in the solution, sonicate for 7 h, and let stand for 24 h.

[0089] (3) Then the ceramic particles after standing are dried at 120°C and then placed in a muffle furnace at 300°C for 120 min.

[0090] (4) After repeating steps (2) and (3) three times alternately, the active ceramic particles are reduced in H2 atmosphere (200℃; flow rate 100 mL / min) for 5 h to obtain Pd-In modified three-dimensional ceramic particle electrode.

[0091] The other preparation process is the same as in Example 1.

[0092] Effect test

[0093] The specific operation mode of the electrocatalytic reduction-oxidation reactor is as follows: wastewater enters the cathode chamber under the action of the influent pump to undergo a cathodic reduction reaction, and then enters the anode chamber to undergo an oxidation reaction before being discharged. The cathode and anode chambers are separated by an ion exchange membrane to achieve independence between the cathode and anode chambers. The ion exchange membrane size is 80 mm × 80 mm. The cross-sectional area of ​​the "serpentine" space in the cathode / anode chamber is as follows. Figure 3 As shown, it is 30 mm wide, 15 mm high, and 305 mm long.

[0094] Test Example 1: Simulated wastewater for the degradation of polyhalogenated organic compounds, trichloronitrobenzene

[0095] The reactors prepared in Examples 1-3 and Comparative Examples 1-2 were used to treat simulated wastewater containing trichloronitrobenzene, a typical polyhalogenated organic compound, in continuous flow operation. The experimental parameters were: initial concentration of trichloronitrobenzene in the influent was 10 mg / L; current density was 10 mA / cm². 2 The electrolyte Na2SO4 concentration was 50 mM; the hydraulic residence time in a single chamber was 3 min. The test results are shown in Table 1.

[0096] Test Example 2: Degradation of perfluorooctane sulfonic acid (PFOS) in simulated wastewater

[0097] The reactors prepared in Examples 1-3 and Comparative Examples 1-2 were used to treat simulated wastewater containing perfluorooctane sulfonic acid (PFOS), a typical perhalogenated organic compound, in continuous flow operation. The experimental parameters were: initial PFOS concentration in the influent was 5 mg / L; current density was 10 mA / cm². 2 The electrolyte Na2SO4 concentration was 50 mM; the hydraulic residence time in a single chamber was 5 min. The test results are shown in Table 1.

[0098] Table 1. Test results of simulated wastewater containing degraded poly / full-halogenated organic compounds

[0099]

[0100] Test Example 3: Stability and Repeatability Test

[0101] After using the reactors of Examples 1-3 in continuous flow operation mode to degrade the simulated wastewater containing trichloronitrobenzene, a typical polyhalogenated organic compound in Test Example 1, and the simulated wastewater containing perfluorooctane sulfonic acid (PFOS), a typical perhalogenated organic compound in Test Example 2, for 10 h, the removal rate was maintained at over 90%.

[0102] The above detailed description is a specific description of one of the feasible embodiments of the present invention. This embodiment is not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included within the scope of the technical solution of the present invention.

Claims

1. An electrocatalytic reduction-oxidation reaction apparatus for degrading fully halogenated or polyhalogenated organic compounds, comprising a reactor (4), a power source (12), a peristaltic pump (3), an inlet tank (1), and an outlet tank (11), characterized in that, The reactor (4) is divided into a cathode chamber and an anode chamber by a proton exchange membrane; the anode chamber is a graphite sheet (9) and a three-dimensional ceramic particle electrode (8) modified with Sn-Sb-Ag, and the cathode chamber is a titanium sheet (5) and a three-dimensional ceramic particle electrode (6) modified with Pd-In; the positive and negative terminals of the power supply (12) are connected to the anode and cathode of the reactor (4) respectively by wires; The anode is a graphite sheet (9), the cathode is a titanium sheet (5), the cathode and the anode are located on opposite sides of the reactor, and the Sn-Sb-Ag modified three-dimensional ceramic particle electrode (8) and the Pd-In modified three-dimensional ceramic particle electrode (6) are separated by a proton exchange membrane (7). Both the cathode chamber and the anode chamber are "serpentine" spaces; the Sn-Sb-Ag modified three-dimensional ceramic particle electrode (8) and the Pd-In modified three-dimensional ceramic particle electrode (6) are placed in the "serpentine" spaces of the anode chamber and the cathode chamber, respectively.

2. The electrocatalytic reduction-oxidation reaction apparatus according to claim 1, characterized in that, The cathode chamber and the anode chamber are each provided with an inlet and an outlet; the inlet pool (1) and the peristaltic pump (3) are connected to the inlet of the cathode chamber through the inlet pipe (2), the outlet pool (11) is connected to the outlet of the anode chamber through the outlet pipe (10), and the outlet of the cathode chamber is connected to the inlet of the anode chamber.

3. The electrocatalytic reduction-oxidation reaction apparatus according to claim 1, characterized in that, The thickness of the proton exchange membrane (7) is 0.4-0.5 mm.

4. The electrocatalytic reduction-oxidation reaction apparatus according to claim 1, characterized in that, The preparation method of the Sn-Sb-Ag modified three-dimensional ceramic particle electrode (6) includes: S1: Ceramic microparticles are etched in boiling hydrochloric acid and then washed with water to obtain pretreated ceramic microparticles; S2: The pretreated ceramic particles are soaked in AgNO3 aqueous solution, dried, and calcined; S3: Take the ceramic particles treated by S2, soak them in an ethanol solution containing SnCl4 and SbCl3, dry them, and calcine them; S4: Repeat steps S2 and S3 alternately 3-6 times to obtain the result.

5. The electrocatalytic reduction-oxidation reaction apparatus according to claim 4, characterized in that, The ceramic microparticles mentioned in step S1 are spherical alumina ceramic particles with an open pore structure; the spherical alumina ceramic particles, by mass percentage, comprise 70-75% SiO2, 20-25% Al2O3, 2-4% K2O, and 0.5-1.5% Fe2O3; the particle size of the spherical alumina ceramic particles is 2.5-4.0 mm, and the density is 1.6-2.0 g / cm³. -3 The pore volume is 0.1-0.15 cm³. 3 / g.

6. The electrocatalytic reduction-oxidation reaction apparatus according to claim 4, characterized in that, In step S1, the hydrochloric acid has a mass fraction of 12-24%, the etching time is 20-40 min, the water washing is ultrasonic water washing, the water washing time is 5-15 min, and the number of water washings is 2-3 times.

7. The electrocatalytic reduction-oxidation reaction apparatus according to claim 4, characterized in that, In step S2, the concentration of the AgNO3 aqueous solution is 0.02-0.05 M, the soaking time is 0.3-0.6 h, the drying temperature is 100-110℃, and the drying time is 8-15 min; the calcination temperature is 400-500℃, and the calcination time is 0.5-1.5 h.

8. The electrocatalytic reduction-oxidation reaction apparatus according to claim 4, characterized in that, In step S3, the concentrations of SnCl4 and SbCl3 are 0.25-0.35 M and 0.02-0.03 M, respectively; the soaking time is 0.3-0.6 h; the drying temperature is 100-110℃; and the drying time is 8-15 min. The calcination temperature is 400-500℃; and the calcination time is 0.5-1.5 h.

9. The electrocatalytic reduction-oxidation reaction apparatus according to claim 1, characterized in that, The preparation method of the Pd-In modified three-dimensional ceramic particle electrode (8) includes: (1) The pretreated ceramic particles were immersed in a mixed solution of PdCl2 and InCl3, sonicated, allowed to stand, dried, and calcined. (2) Repeat step (1) 2-4 times, then reduce in an H2 atmosphere to obtain the product.

10. The electrocatalytic reduction-oxidation reaction apparatus according to claim 9, characterized in that, The solvent of the mixed solution in step (1) is a 0.05-0.15 M HCl solution; the concentrations of PdCl2 and InCl3 in the mixed solution are both 0.2-0.35 M; the molar ratio of Pb:In in the mixed solution is 1:0.5-2; the ultrasonication time is 5-8 h, and the standing time is 20-30 h; the drying temperature is 100-130℃, the calcination temperature is 280-320℃, and the calcination time is 100-130 min.

11. The electrocatalytic reduction-oxidation reaction apparatus according to claim 9, characterized in that, The reduction temperature in step (2) is 180-220℃, and the reduction time is 4-6 h; the flow rate of H2 is 80-120 mL / min.

12. The application of the electrocatalytic reduction-oxidation reaction device according to any one of claims 1-11 in the degradation of all-halogenated or polyhalogenated organic compounds in water.

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