System and device for electrochemical synthesis of hydrogen peroxide and preparation method

Abstract

The invention relates to the technical field of hydrogen peroxide synthesis, and discloses a hydrogen peroxide electrochemical synthesis device which comprises a movable modular box body, a fluid treatment module, a reaction module, a detection module, a safety module and a temperature control module, the fluid treatment module is arranged in the movable modular box body and comprises an alkali liquor box, a cathode process circulating pump, an anode process circulating pump, an anode alkali supplementing pump, a pure water inlet and a product collecting box; the reaction module is arranged in the middle of the movable modular box body and comprises a plate frame type electrolytic cell, a cathode gas-liquid separator and an anode gas-liquid separator, an outlet of a cathode of the plate frame type electrolytic cell is communicated with an inlet in the top of the cathode gas-liquid separator, and an outlet of an anode of the plate frame type electrolytic cell is communicated with an inlet in the top of the anode gas-liquid separator; the mode that a traditional intermittent electrolytic cell frequently stops to change liquid is abandoned, and continuous production is achieved through the cathode process circulating pump, the anode process circulating pump, the gas-liquid separator and closed-loop control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydrogen peroxide synthesis, in particular to a system and device for electrochemically synthesizing hydrogen peroxide and a preparation method. BACKGROUND

[0002] Hydrogen peroxide (H2O2) is a green oxidant with great application value. It plays an important role in medical disinfection, wastewater treatment, chemical synthesis, and new energy due to its strong oxidation ability and clean reaction products. Currently, the global industrial production mainly adopts the anthraquinone method, which includes hydrogenation, oxidation, extraction, and purification. The complete industrial production system has an annual production capacity of millions of tons. However, the anthraquinone method has problems such as complex process, high energy consumption, use of organic solvents and noble metal catalysts, and faces pressure for transformation and upgrading under increasingly stringent environmental policies.

[0003] Under this background, electrochemical synthesis of hydrogen peroxide technology has become a research hotspot due to its unique advantages. This technology directly synthesizes H2O2 through a two-electron reduction reaction (2e-ORR, O2+2H + +2e - →H2O2) of oxygen at the cathode. It has the characteristics of mild reaction conditions (normal temperature and pressure), environmental friendliness (no need for organic solvents), high atom economy, and the ability to achieve distributed production. However, the electrochemical synthesis of H2O2 technology still faces many challenges for large-scale industrial application: first, in terms of materials, the activity and selectivity of existing electrode catalysts are difficult to balance, and the long-term stability is insufficient; second, in terms of engineering, the reactor design faces problems such as mass transfer limitation and gas diffusion electrode wetting, resulting in low current density and energy efficiency; third, in terms of safety control, the decomposition characteristics of H2O2 make it risky to accumulate high-concentration products online, posing a serious challenge to the miniaturization and distributed application of the system. Solving these problems requires the collaborative innovation of materials science, electrochemical engineering, and process safety, and is a key direction for both academia and industry.

[0004] Defects and deficiencies of the prior art: (1) The traditional anthraquinone method has significant defects: The process is complex and lengthy, involving multiple steps such as hydrogenation, oxidation, and extraction. It requires large equipment investment and high energy consumption, uses a large amount of organic solvents (such as heavy aromatic hydrocarbons and tri-octyl phosphate), generates toxic waste, and must produce high-concentration (>27.5%) products. The subsequent dilution for use increases the risk of transportation and storage, and the device size is large, making it only suitable for centralized production and unable to meet the needs of distributed production. (2) Main problems of existing electrochemical synthesis technology: Unreasonable reactor design: low mass transfer efficiency, limited yield by oxygen solubility in electrolyte; uneven flow field distribution, performance sharply decreased after scale-up; lack of integrated design, large space occupied by auxiliary equipment; poor long-term operation stability, active components easily lost; Safety control missing: no real-time gas monitoring system, high risk of H2 / O2 mixture explosion; lack of automatic protection mechanism, potential safety hazard; large application limitations: bulky equipment, difficult to move; large fluctuation of product concentration, difficult to accurately control; short continuous operation time (usually <500 hours), frequent maintenance.

[0005] Limitations of other alternative technologies: Photocatalytic method: low quantum efficiency, energy utilization rate less than 5%, catalyst easily deactivated, short service life; difficult to achieve continuous production; hydrogen-oxygen direct synthesis method; harsh reaction conditions, high pressure environment required; high safety risk, inert gas protection required; complex equipment, high cost; In summary, the existing hydrogen peroxide production technologies generally have high energy consumption, high pollution, poor safety, and are difficult to miniaturize, which seriously restricts their application in distributed scenarios. There is an urgent need for safe, convenient, and mobile disinfectant production equipment, and new hydrogen peroxide preparation technologies need to be developed.

[0006] Therefore, an electrochemical synthesis system, device and preparation method of hydrogen peroxide are proposed. SUMMARY

[0007] The purpose of the present application is to provide an electrochemical synthesis system, device and preparation method of hydrogen peroxide, thereby solving or at least alleviating one or more of the above problems and other aspects of the prior art.

[0008] To achieve the above-mentioned purpose, the present application provides the following technical solutions: an electrochemical synthesis device of hydrogen peroxide, comprising a movable modular box, a fluid treatment module and a reaction module; The fluid treatment module is arranged inside the movable modular box, and the fluid treatment module comprises a lye tank, a cathode process circulating pump, an anode process circulating pump, an anode alkali supplementing pump, a pure water inlet and a product collection tank. The reaction module is arranged in the middle of the movable modular box, and the reaction module comprises a plate-and-frame electrolytic cell, a cathode gas-liquid separator and an anode gas-liquid separator, the outlet of the cathode of the plate-and-frame electrolytic cell is communicated with the inlet at the top of the cathode gas-liquid separator, and the anode outlet of the plate-and-frame electrolytic cell is communicated with the inlet at the top of the anode gas-liquid separator. The alkali liquor tank outlet is connected with the inlet of the anode gas-liquid separator through the anode alkali supplement pump, the inlet of the cathode process circulation pump is communicated with the bottom of the cathode gas-liquid separator, the outlet of the cathode process circulation pump is communicated with the inlet of the cathode of the plate-frame electrolytic cell, the inlet of the anode process circulation pump is communicated with the bottom of the anode gas-liquid separator, the outlet of the anode process circulation pump is communicated with the inlet of the anode of the plate-frame electrolytic cell, the pure water inlet is respectively communicated with the cathode gas-liquid separator and the anode gas-liquid separator through pipelines, the product collecting tank is communicated with the outlet of the cathode gas-liquid separator, and the outlet at the upper end of the anode gas-liquid separator is communicated with the inlet of the cathode of the plate-frame electrolytic cell through a circulation pipeline.

[0009] Optionally, the safety module comprises a first oxygen emergency cut-off valve, a second oxygen emergency cut-off valve, a high-purity nitrogen source inlet, a nitrogen cut-off valve, a cathode gas-liquid separator safety valve, an anode gas-liquid separator safety valve, an oxygen detector and a high-purity oxygen inlet, the first oxygen emergency cut-off valve and the second oxygen emergency cut-off valve are connected in parallel on the gas outlet pipeline of the anode gas-liquid separator, the gas outlet of the first oxygen emergency cut-off valve and the gas outlet of the second oxygen emergency cut-off valve are both communicated with an oxygen release port, the high-purity nitrogen source inlet is communicated with the top of the cathode gas-liquid separator and the top of the anode gas-liquid separator through the nitrogen cut-off valve, the cathode gas-liquid separator safety valve and the anode gas-liquid separator safety valve are respectively arranged at the top of the cathode gas-liquid separator and the top of the anode gas-liquid separator, the oxygen detector is arranged at the bottom of the movable modular box, the high-purity oxygen inlet is communicated with the inlet of the cathode of the plate-frame electrolytic cell through an oxygen supply pipeline, and a flow meter is arranged in series on the oxygen supply pipeline.

[0010] Optionally, the safety module comprises a first oxygen emergency cut-off valve, a second oxygen emergency cut-off valve, a high-purity nitrogen source inlet, a nitrogen cut-off valve, a cathode gas-liquid separator safety valve, an anode gas-liquid separator safety valve, an oxygen detector and a high-purity oxygen inlet, the first oxygen emergency cut-off valve and the second oxygen emergency cut-off valve are connected in parallel on the gas outlet pipeline of the anode gas-liquid separator, the gas outlet of the first oxygen emergency cut-off valve and the gas outlet of the second oxygen emergency cut-off valve are both communicated with an oxygen release port, the high-purity nitrogen source inlet is communicated with the top of the cathode gas-liquid separator and the top of the anode gas-liquid separator through the nitrogen cut-off valve, the cathode gas-liquid separator safety valve and the anode gas-liquid separator safety valve are respectively arranged at the top of the cathode gas-liquid separator and the top of the anode gas-liquid separator, the oxygen detector is arranged at the bottom of the movable modular box, the high-purity oxygen inlet is communicated with the inlet of the cathode of the plate-frame electrolytic cell through an oxygen supply pipeline, and a flow meter is arranged in series on the oxygen supply pipeline.

[0011] Optionally, the system also includes a temperature control module, which comprises a cathode heat exchanger, an anode heat exchanger, a refrigeration unit, and a cathode gas-liquid separator heat exchanger. The cathode heat exchanger is connected in series in the pipeline between the cathode process circulation pump and the cathode inlet of the plate and frame electrolytic cell. The anode heat exchanger is connected in series in the pipeline between the anode process circulation pump and the anode inlet of the plate and frame electrolytic cell. The cathode gas-liquid separator heat exchanger is sleeved on the outside of the cathode gas-liquid separator. The refrigeration unit is connected to the cooling water inlets of the cathode heat exchanger, the anode heat exchanger, and the cathode gas-liquid separator heat exchanger via pipelines. The cooling water outlets of the cathode heat exchanger, the anode heat exchanger, and the cathode gas-liquid separator heat exchanger are all connected to the cooling water return port of the refrigeration unit.

[0012] Optionally, the fluid processing module further includes a hydrogen peroxide internal / external circulation switching valve, a hydrogen peroxide internal circulation valve, a cathode gas-liquid separator ultrapure water supply valve, and an anode gas-liquid separator ultrapure water supply valve. One end of the hydrogen peroxide internal / external circulation switching valve is connected to the bottom outlet of the cathode gas-liquid separator, and the other end is connected to the hydrogen peroxide internal circulation valve and the product outlet valve, respectively. The end of the hydrogen peroxide internal circulation valve away from the hydrogen peroxide internal / external circulation switching valve is connected to the top inlet of the cathode gas-liquid separator. The end of the product outlet valve away from the hydrogen peroxide internal / external circulation switching valve is connected to the product collection tank. The cathode gas-liquid separator ultrapure water supply valve is connected in series in the pipeline between the pure water inlet and the cathode gas-liquid separator. The anode gas-liquid separator ultrapure water supply valve is connected in series in the pipeline between the pure water inlet and the anode gas-liquid separator.

[0013] Optionally, the alkali tank level sensor, the cathode gas-liquid separator level sensor, and the anode gas-liquid separator level sensor are all capacitive sensors and are installed vertically along the corresponding container sidewalls; the electrolytic cell cathode inlet temperature sensor, the electrolytic cell cathode outlet temperature transmitter, the electrolytic cell anode inlet temperature sensor, the electrolytic cell anode outlet temperature sensor, the cathode gas-liquid separator temperature sensor, and the anode gas-liquid separator temperature sensor are all PT100 resistance thermometers and are inserted into the corresponding pipes or container walls; the electrolytic cell cathode inlet pressure sensor and the anode gas-liquid separator pressure sensor are both piezoelectric sensors.

[0014] Optionally, both the first and second oxygen emergency shut-off valves are electromagnetically driven butterfly valves, and the nitrogen shut-off valve is a normally closed solenoid valve; both the cathode gas-liquid separator safety valve and the anode gas-liquid separator safety valve are spring-loaded safety valves, with the cathode gas-liquid separator safety valve having a starting pressure of 1.2 MPa and the anode gas-liquid separator safety valve having a starting pressure of 1.2 MPa.

[0015] Optionally, the temperature control module further includes a cathode heat exchanger cooling water valve, an anode heat exchanger cooling water valve, and a cathode gas-liquid separator heat exchanger cooling water valve. The cathode heat exchanger cooling water valve is connected in series in the pipeline between the refrigeration unit and the cooling water inlet of the cathode heat exchanger. The anode heat exchanger cooling water valve is connected in series in the pipeline between the refrigeration unit and the cooling water inlet of the anode heat exchanger. The cathode gas-liquid separator heat exchanger cooling water valve is connected in series in the pipeline between the refrigeration unit and the cooling water inlet of the cathode gas-liquid separator heat exchanger. Both the cathode heat exchanger and the anode heat exchanger are plate heat exchangers.

[0016] The present invention also provides a system for electrochemical synthesis of hydrogen peroxide, including a PLC controller and the above-mentioned device, wherein the PLC controller is electrically connected to the fluid processing module, the reaction module, the detection module, the safety module and the temperature control module respectively.

[0017] This invention also provides a method for preparing hydrogen peroxide by electrochemical synthesis, using the aforementioned system for preparing hydrogen peroxide by electrochemical synthesis, specifically including the following steps: S1: System initialization and lazy purging: The PLC controller sends a command to open the nitrogen shut-off valve, allowing high-purity nitrogen gas with a purity ≥99.99% to enter the high-purity nitrogen source inlet, and controlling the nitrogen pressure to stabilize at 0.4MPa. The high-purity nitrogen gas then enters the cathode gas-liquid separator, anode gas-liquid separator, and the anode and cathode pipelines of the plate and frame electrolytic cell to purge the entire system for 5 minutes to replace residual air and eliminate the risk of explosion from the mixing of oxygen and air. During the purging process, the PLC controller monitors the pressure sensor data of the cathode gas-liquid separator and the anode gas-liquid separator in real time to ensure that the system pressure does not exceed 0.6MPa. After the purging is completed, the nitrogen shut-off valve is closed.

[0018] S2: Graded material supply and parameter calibration: S2.1 Ultrapure Water Supply: The PLC controller opens the ultrapure water supply valves of the cathode gas-liquid separator and the anode gas-liquid separator, allowing ultrapure water to be injected into the cathode gas-liquid separator and the anode gas-liquid separator respectively through the pure water inlet; the ultrapure water injection flow rate is controlled at 5-10L / h, and the liquid level is fed back in real time through the liquid level sensors of the cathode gas-liquid separator and the anode gas-liquid separator. When the liquid level reaches 50% of the total volume of the container, the above two supply valves are closed; S2.2 Alkali replenishment: The PLC controller starts the anode alkali replenishment pump to inject 30wt% sodium hydroxide solution from the alkali tank into the anode gas-liquid separator. The injection flow rate is controlled at 0.1-0.2 L / min. The remaining liquid level in the alkali tank is monitored by the alkali tank level sensor. When the liquid level in the anode gas-liquid separator is stable at 50%, the anode alkali replenishment pump is turned off. S2.3 Oxygen Supply: The PLC controller opens the gas supply valve of the high-purity oxygen inlet, and introduces oxygen with a purity of 90% to 95% into the cathode chamber of the plate and frame electrolytic cell. The oxygen flow rate is controlled at 3 to 6 L / min. The oxygen purity is calibrated in real time by a micro oxygen sensor to ensure that the oxygen purity entering the cathode chamber is not less than 90%.

[0019] S3: Constant Temperature and Pressure Electrolysis Reaction and Dynamic Control: S3.1 Circulation System Start-up: The PLC controller starts the cathode process circulation pump and the anode process circulation pump, controls the flow rate of the cathode process circulation pump to 0.05~0.2L / min, and transports the liquid in the cathode gas-liquid separator to the cathode heat exchanger; controls the flow rate of the anode process circulation pump to 0.05~0.2L / min, and transports the liquid in the anode gas-liquid separator to the anode heat exchanger. S3.2 Temperature Control Linkage: The PLC controller starts the valves of the refrigeration unit and the temperature control module. Based on the detection data of the cathode liquid inlet temperature sensor and the anode liquid inlet temperature sensor of the electrolytic cell, the PLC controller dynamically adjusts the opening of the cathode heat exchanger cooling water valve, the anode heat exchanger cooling water valve and the cathode gas-liquid separator heat exchanger cooling water valve through the PID algorithm to maintain the cathode liquid inlet temperature and the anode liquid inlet temperature at 10±0.5℃. The temperature inside the cathode gas-liquid separator is monitored by the cathode gas-liquid separator temperature sensor to ensure that it does not exceed 12℃. S3.3 Electrolysis Start-up and Parameter Maintenance: Apply a DC voltage of 20–40V to the plate and frame electrolytic cell, and adjust the current output through the PLC controller to maintain a current density of 100–300mA / cm². 2 During electrolysis, the inlet pressure is monitored in real time by the cathode inlet pressure sensor and the anode inlet pressure sensor of the electrolytic cell. When the pressure is >0.6MPa, the corresponding circulation pump speed is reduced by 10% to 15%, and when the pressure is <0.3MPa, the corresponding circulation pump speed is increased by 10% to 15% to ensure that the pressure is stable at 0.3-0.6MPa. S3.4 Electrode reaction: Oxygen reduction reaction occurs in the cathode chamber of the plate and frame electrolytic cell: O2 + 2H+ + +2e - →H₂O₂, producing a gas-liquid mixture containing hydrogen peroxide; oxygen evolution reaction occurs in the anode chamber: 4OH⁻ - →O2↑+2H2O+4e - This produces an oxygen-containing gas-liquid mixture.

[0020] S4: Gas-liquid separation, product collection and resource recycling: S4.1 Gas-liquid separation: The gas-liquid mixture containing hydrogen peroxide enters the cathode gas-liquid separator from the cathode outlet of the plate and frame electrolyzer. After separation by the internal baffles, the liquid collects at the bottom of the separator and flows back to the inlet of the cathode process circulation pump. The separated gas is transported through the top pipeline of the cathode gas-liquid separator. Along the way, the hydrogen concentration is detected by an electrochemical trace hydrogen analyzer. If the hydrogen concentration is ≤1000ppm, the gas is returned to the cathode chamber of the plate and frame electrolyzer. If the hydrogen concentration is >1000ppm, the PLC controller triggers an audible and visual alarm. If it is >2000ppm, the electrolysis power supply is immediately cut off and the nitrogen purging program is restarted. The oxygen-containing gas-liquid mixture enters the anode gas-liquid separator from the anode outlet of the plate and frame electrolytic cell. After being separated by internal baffles, the liquid collects at the bottom of the separator and flows back to the inlet of the anode process circulation pump. The separated gas is transported through the circulation pipeline at the top of the anode gas-liquid separator. The oxygen purity is detected by a micro oxygen sensor. When the purity is >85%, the PLC controller opens the oxygen circulation valve to return the gas to the cathode chamber of the plate and frame electrolytic cell to improve the oxygen utilization rate. When the purity is ≤85%, the first oxygen emergency shut-off valve or the second oxygen emergency shut-off valve is opened to allow the gas to be discharged through the oxygen vent. S4.2 Product Collection: The PLC controller determines the hydrogen peroxide concentration in the cathode gas-liquid separator by inferring logic based on the electrolysis time and circulating liquid concentration. When the concentration reaches 1% to 3%, the PLC controller switches the internal / external circulation valve of hydrogen peroxide to connect with the product outlet valve, allowing the hydrogen peroxide solution to enter the product collection tank. When the concentration does not meet the standard, the internal / external circulation valve of hydrogen peroxide remains connected with the internal circulation valve of hydrogen peroxide, and the liquid flows back to the inside of the cathode gas-liquid separator, and is then output to the plate and frame electrolyzer via the cathode process circulation pump for further concentration. S4.3 Safety and Liquid Level Control: During the process, if the oxygen detector detects that the oxygen concentration in the movable modular box is >23%, the PLC controller will immediately close the first and second oxygen emergency shut-off valves and open the nitrogen shut-off valve for inertial purging; if the cathode gas-liquid separator liquid level sensor detects that the liquid level is <20%, the cathode gas-liquid separator ultrapure water supply valve will be automatically opened and closed after the liquid level is restored to 50%.

[0021] Compared with the prior art, the beneficial effects of the present invention are: This invention, through a modular and compact integrated design, highly integrates core components such as electrolytic cells, circulating pumps, gas-liquid separators, and control units into a mobile housing, solving the pain point of traditional electrochemical synthesis devices being "large in size and fixed in deployment"—it can meet the centralized production needs of industries such as chemical and electronics, and can also be flexibly transported to distributed scenarios such as medical disinfection sites, emergency field operations, and university research laboratories, filling the gap in existing technologies that cannot achieve "real-time and scenario-based production"; Abandoning the traditional intermittent electrolytic cell model of "frequent shutdowns for liquid replacement", continuous production is achieved by using cathode process circulating pumps, anode process circulating pumps, gas-liquid separators, and closed-loop control. Directly synthesizing 1%–3% hydrogen peroxide solutions avoids the drawbacks of existing gas diffusion electrode systems, which require additional concentration (energy consumption of 4–6 kWh / kg) due to product concentrations <0.5%, significantly reducing subsequent processing energy consumption and costs. Simultaneously, through PID temperature control (±0.5℃) and multi-parameter regulation, product concentration fluctuations are minimized, and quality stability is greatly improved. Furthermore, the use of a bidirectional check valve in the oxygen reuse pipeline, hydrogen concentration interlock, and real-time monitoring with a trace hydrogen analyzer, combined with nitrogen purging and replacement of residual air in the system, significantly reduces the risk of hydrogen-related accidents. A spring-loaded safety valve is configured to prevent overpressure in the gas-liquid separator, and a three-stage liquid level interlock between the alkali tank and the gas-liquid separator prevents the electrodes from dry burning. Waste of raw materials is reduced by "returning oxygen from the anode to the cathode"; ultrapure water and alkali solution are replenished as needed to avoid excessive consumption of reagents; By adopting "on-demand cooling design" combined with PID algorithm to regulate heat exchange efficiency, the energy waste of "full power operation" in traditional systems is avoided; at the same time, the "organic waste liquid treatment" of the anthraquinone method and the "energy consumption of the concentration process" of the existing electrochemical system are eliminated, and the overall operating cost is significantly reduced. By linking the sensor network with the PLC controller, the entire process of "system initialization - material supply - electrolysis reaction - product collection - emergency handling" can be automated without frequent manual adjustments. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the connection structure of the cathode gas-liquid separator in the electrochemical hydrogen peroxide synthesis apparatus of the present invention. Figure 2 This is a schematic diagram of the connection structure of the anode gas-liquid separator in the electrochemical hydrogen peroxide synthesis apparatus of the present invention; Figure 3 This is a schematic diagram of the connection structure of the refrigeration unit in the electrochemical synthesis of hydrogen peroxide apparatus of the present invention; Figure 4 This is a schematic diagram of the installation structure of the anode heat exchanger in the electrochemical synthesis of hydrogen peroxide apparatus of the present invention; Figure 5 This is a schematic diagram of the installation structure of the cathode gas-liquid separator in the electrochemical hydrogen peroxide synthesis apparatus of the present invention; Figure 6 This is a schematic diagram of the installation structure of the anode alkali replenishment pump in the electrochemical synthesis of hydrogen peroxide apparatus of the present invention; Figure 7 This is a schematic diagram of the installation structure of the cathode heat exchanger in the electrochemical hydrogen peroxide synthesis apparatus of the present invention. Figure 8This is a schematic diagram of the installation structure of the plate-and-frame electrolyzer in the apparatus for electrochemical synthesis of hydrogen peroxide of the present invention. Figure 9 This is a schematic diagram of the installation structure of the cathode process circulation pump in the electrochemical synthesis of hydrogen peroxide apparatus of the present invention. Figure 10 This is a schematic diagram of the installation structure of the pure water inlet in the electrochemical hydrogen peroxide synthesis apparatus of the present invention; Figure 11 This is a schematic diagram of the installation structure of the anode alkali replenishment pump control valve in the electrochemical synthesis of hydrogen peroxide apparatus of the present invention; Figure 12 This is a schematic diagram of the installation structure of the high-purity oxygen inlet in the electrochemical hydrogen peroxide synthesis apparatus of the present invention; Figure 13 This is a schematic diagram of the installation structure of the alkali tank in the electrochemical synthesis of hydrogen peroxide apparatus of the present invention; Figure 14 This is a schematic diagram of the installation structure of the alkali tank level sensor in the electrochemical synthesis of hydrogen peroxide apparatus of the present invention.

[0023] In the diagram: 1. Movable modular housing; 1001. Casters; 2. Alkali solution tank; 3. Cathode process circulating pump; 4. Anode process circulating pump; 5. Anode alkali replenishment pump; 6. Refrigeration unit; 7. High-purity oxygen inlet; 8. Plate and frame electrolytic cell; 9. Cathode gas-liquid separator; 901. Cathode gas-liquid separator heat exchanger; 10. Anode gas-liquid separator; 11. Cathode heat exchanger; 12. Anode heat exchanger; 13. Product collection box; 14. Pure water inlet; 101. Alkali tank level sensor; 102. Cathode gas-liquid separator level sensor; 103. Anode gas-liquid separator level sensor; 104. Electrolytic cell cathode inlet temperature sensor; 1041. Electrolytic cell cathode outlet temperature transmitter; 1042. Electrolytic cell cathode inlet pressure sensor; 105. Electrolytic cell anode inlet temperature sensor; 1051. Electrolytic cell anode inlet pressure sensor; 106. Electrolytic cell anode outlet temperature sensor; 107. Cathode gas-liquid separator temperature sensor; 108. Anode gas-liquid separator temperature sensor; 109. Cathode gas-liquid separator pressure sensor; 110. Anode gas-liquid separator pressure sensor; 111. Trace hydrogen analyzer; 112. Trace oxygen sensor; 113. Oxygen circulation valve; 201. Hydrogen peroxide internal / external circulation switching valve; 202. Hydrogen peroxide internal circulation valve; 203. Product outlet valve; 204. Cathode heat exchanger cooling water valve; 205. Anode heat exchanger cooling water valve; 206. Anode alkali replenishment pump control valve; 2071. Cathode gas-liquid separator ultrapure water supply valve; 2072. Anode gas-liquid separator ultrapure water supply valve; 208. Cathode gas-liquid separator heat exchanger cooling water valve; 300. PLC controller; 401. First oxygen emergency shut-off valve; 402. Second oxygen emergency shut-off valve; 421. Oxygen vent; 403. High-purity nitrogen source inlet; 404. Nitrogen shut-off valve; 405. Cathode gas-liquid separator safety valve; 406. Anode gas-liquid separator safety valve; 407. Oxygen detector. Detailed Implementation

[0024] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0025] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual images. They should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0026] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0027] In the description of this invention, unless otherwise explicitly specified and limited, the term "connection" or similar designation indicating a connection between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] Example Please see Figures 1 to 14 This embodiment provides an apparatus for the electrochemical synthesis of hydrogen peroxide, including a movable modular housing 1, a fluid processing module, and a reaction module; The fluid processing module is located inside the movable modular housing 1. The fluid processing module includes an alkali tank 2, a cathode process circulation pump 3, an anode process circulation pump 4, an anode alkali replenishment pump 5, a pure water inlet 14, and a product collection tank 13. The reaction module is located in the middle of the movable modular box 1. The reaction module includes a plate and frame electrolytic cell 8, a cathode gas-liquid separator 9 and an anode gas-liquid separator 10. The cathode outlet of the plate and frame electrolytic cell 8 is connected to the inlet at the top of the cathode gas-liquid separator 9, and the anode outlet of the plate and frame electrolytic cell 8 is connected to the inlet at the top of the anode gas-liquid separator 10. The outlet of the alkali tank 2 is connected to the inlet of the anode gas-liquid separator 10 via the anode replenishing pump 5. The inlet of the cathode process circulation pump 3 is connected to the bottom of the cathode gas-liquid separator 9, and the outlet of the cathode process circulation pump 3 is connected to the cathode inlet of the plate and frame electrolytic cell 8. The inlet of the anode process circulation pump 4 is connected to the bottom of the anode gas-liquid separator 10, and the outlet of the anode process circulation pump 4 is connected to the anode inlet of the plate and frame electrolytic cell 8. The pure water inlet 14 is connected to the cathode gas-liquid separator 9 and the anode gas-liquid separator 10 via pipelines. The product collection box 13 is connected to the outlet of the cathode gas-liquid separator 9. The outlet at the top of the anode gas-liquid separator 10 is connected to the cathode inlet of the plate and frame electrolytic cell 8 via a circulation pipeline.

[0029] By adopting the above technical solution, the movable modular housing 1 provides an installation carrier for the fluid processing module and the reaction module, realizing the mobility of the device; in the fluid processing module, the alkali solution in the alkali tank 2 is transported to the anode gas-liquid separator 10 via the anode alkali replenishment pump 5 to replenish electrolyte for the anode reaction; the pure water inlet 14 replenishes ultrapure water to the cathode gas-liquid separator 9 and the anode gas-liquid separator 10; the cathode process circulation pump 3 transports the liquid at the bottom of the cathode gas-liquid separator 9 to the cathode inlet of the plate and frame electrolytic cell 8; and the anode process circulation pump 4 transports the liquid at the bottom of the anode gas-liquid separator 10 to the plate and frame electrolytic cell 8. The anode inlet of the frame electrolytic cell 8 forms a liquid circulation between the cathode and anode. In the reaction module, the hydrogen peroxide-containing gas-liquid mixture discharged from the cathode outlet of the plate-and-frame electrolytic cell 8 enters the top of the cathode gas-liquid separator 9, and the oxygen-containing gas-liquid mixture discharged from the anode outlet enters the top of the anode gas-liquid separator 10. After separation, the outlet of the cathode gas-liquid separator 9 conveys the product to the product collection box 13. The upper outlet of the anode gas-liquid separator 10 returns the separated oxygen to the cathode inlet of the plate-and-frame electrolytic cell 8 through the circulation pipeline, realizing oxygen recovery and utilization, and finally completing the continuous operation of electrochemical synthesis of hydrogen peroxide.

[0030] In this embodiment, a proton exchange membrane is provided inside the plate and frame electrolytic cell 8, which divides the interior of the plate and frame electrolytic cell 8 into a cathode chamber and an anode chamber. A titanium alloy-based gas diffusion electrode is provided inside the cathode chamber, and a nickel-based oxygen evolution electrode is provided inside the anode chamber. Both the cathode gas-liquid separator 9 and the anode gas-liquid separator 10 are equipped with baffles.

[0031] By adopting the above technical solution, the proton exchange membrane in the plate and frame electrolytic cell 8 precisely divides its interior into a cathode chamber and an anode chamber, preventing the mixing of cathode and anode materials. The titanium alloy-based gas diffusion electrode in the cathode chamber has good conductivity and gas diffusion performance, providing a suitable reaction site for the oxygen reduction reaction at the cathode to generate hydrogen peroxide. The nickel-based oxygen evolution electrode in the anode chamber has excellent oxygen evolution catalytic activity, ensuring the efficient execution of the oxygen evolution reaction at the anode. The inclined baffles inside the cathode gas-liquid separator 9 and the anode gas-liquid separator 10 can extend the residence time of the gas-liquid mixture in the separator, enhance the gas-liquid contact and separation effect, allow the liquid to collect more fully at the bottom of the separator, and allow the gas to be discharged more smoothly from the top, improving the gas-liquid separation efficiency and laying the foundation for subsequent material circulation or product collection.

[0032] The bottom of the movable modular box 1 is fixedly equipped with rollers 1001. In this embodiment, the rollers 1001 are fuma wheels, which facilitate the rapid movement and fixation of the movable modular box 1.

[0033] In this embodiment, a detection module is also included, comprising an alkali tank level sensor 101, a cathode gas-liquid separator level sensor 102, an anode gas-liquid separator level sensor 103, an electrolytic cell cathode inlet temperature sensor 104, an electrolytic cell cathode outlet temperature transmitter 1041, an electrolytic cell cathode inlet pressure sensor 1042, an electrolytic cell anode inlet temperature sensor 105, an electrolytic cell anode inlet pressure sensor 1051, an electrolytic cell anode outlet temperature sensor 106, a cathode gas-liquid separator temperature sensor 107, an anode gas-liquid separator temperature sensor 108, and a cathode gas-liquid separator pressure sensor. The apparatus includes a pressure sensor 110 for the anode gas-liquid separator, an electrochemical trace hydrogen analyzer 111, and a trace oxygen sensor 112. Each sensor is installed on the inlet and outlet pipes of the alkaline tank 2, the cathode gas-liquid separator 9, the anode gas-liquid separator 10, and the plate-and-frame electrolytic cell 8, respectively. The electrochemical trace hydrogen analyzer 111 is connected in series to the gas outlet pipe of the cathode gas-liquid separator 9. The gas outlet pipe of the cathode gas-liquid separator 9 is connected to the inlet of the cathode of the plate-and-frame electrolytic cell 8. The trace oxygen sensor 112 is installed in series on the circulation pipe, and an oxygen circulation valve 113 is installed on the circulation pipe.

[0034] By adopting the above technical solution, each sensor in the detection module monitors the parameters of its corresponding component in real time: Alkali tank level sensor 101 is installed on alkali tank 2 to monitor the alkali level; cathode gas-liquid separator level sensor 102 is installed on cathode gas-liquid separator 9 to monitor its level; anode gas-liquid separator level sensor 103 is installed on anode gas-liquid separator 10 to monitor its level; electrolytic cell cathode inlet temperature sensor 104 and electrolytic cell cathode inlet pressure sensor 1042 are installed on the cathode inlet pipe of plate-and-frame electrolytic cell 8 to monitor the cathode inlet temperature and pressure, respectively; electrolytic cell cathode outlet temperature transmitter 1041 is installed on the cathode outlet pipe of plate-and-frame electrolytic cell 8 to monitor the cathode outlet temperature; electrolytic cell anode inlet temperature sensor 105 and electrolytic cell anode inlet pressure sensor 1051 are installed on the anode inlet pipe of plate-and-frame electrolytic cell 8 to monitor the anode inlet temperature and pressure, respectively. Temperature sensor 106 is installed on the anode outlet pipe of plate and frame electrolytic cell 8 to monitor the anode liquid temperature; cathode gas-liquid separator temperature sensor 107 and cathode gas-liquid separator pressure sensor 109 are installed on cathode gas-liquid separator 9 to monitor its temperature and pressure respectively; anode gas-liquid separator temperature sensor 108 and anode gas-liquid separator pressure sensor 110 are installed on anode gas-liquid separator 10 to monitor its temperature and pressure respectively; electrochemical trace hydrogen analyzer 111 is connected in series in the gas outlet pipe of cathode gas-liquid separator 9, which is connected to the cathode inlet of plate and frame electrolytic cell 8, to detect the hydrogen concentration in the cathode separated gas; trace oxygen sensor 112 is connected in series in the circulation pipe between the upper outlet of anode gas-liquid separator 10 and the cathode inlet of plate and frame electrolytic cell 8, and works with oxygen circulation valve 113 on the circulation pipe to detect the purity of circulating oxygen, providing parameter basis for oxygen recycling and ensuring that system operating parameters can be monitored in real time.

[0035] In this embodiment, a safety module is also included. The safety module includes a first oxygen emergency shut-off valve 401, a second oxygen emergency shut-off valve 402, a high-purity nitrogen source inlet 403, a nitrogen shut-off valve 404, a cathode gas-liquid separator safety valve 405, an anode gas-liquid separator safety valve 406, an oxygen detector 407, and a high-purity oxygen inlet 7. The first oxygen emergency shut-off valve 401 and the second oxygen emergency shut-off valve 402 are connected in parallel to the gas outlet pipeline of the anode gas-liquid separator 10. The outlet of the first oxygen emergency shut-off valve 401 is connected to the outlet of the second oxygen emergency shut-off valve 406. The outlets of 2 are all connected to the oxygen vent 421. The high-purity nitrogen source inlet 403 is connected to the top of the cathode gas-liquid separator 9 and the anode gas-liquid separator 10 through the nitrogen shut-off valve 404. The cathode gas-liquid separator safety valve 405 and the anode gas-liquid separator safety valve 406 are respectively installed on the top of the cathode gas-liquid separator 9 and the anode gas-liquid separator 10. The oxygen detector 407 is installed at the bottom of the movable modular box 1. The high-purity oxygen inlet 7 is connected to the cathode inlet of the oxygen supply pipeline plate frame electrolytic cell 8. A flow meter is installed in series on the oxygen supply pipeline.

[0036] By adopting the above technical solution, the safety module achieves multiple safety protections for the system: the first oxygen emergency shut-off valve 401 and the second oxygen emergency shut-off valve 402 are connected in parallel on the gas outlet pipeline of the anode gas-liquid separator 10. When it is necessary to discharge the anode separated gas, the gas flow can be controlled to the oxygen vent 421 through the two valves. The redundant design improves safety; the high-purity nitrogen source inlet 403 is connected to the top of the cathode gas-liquid separator 9 and the top of the anode gas-liquid separator 10 respectively through the nitrogen shut-off valve 404, which can introduce high-purity nitrogen into the cathode gas-liquid separator 9 and the anode gas-liquid separator 10 for inert blowing. The system is designed to eliminate the risk of explosion. A safety valve 405 for the cathode gas-liquid separator 9 and a safety valve 406 for the anode gas-liquid separator 10 are installed on top of each other. When the pressure inside either the cathode gas-liquid separator 9 or the anode gas-liquid separator 10 exceeds the limit, the safety valve automatically opens to release pressure. An oxygen detector 407 is installed at the bottom of the movable modular housing 1 to monitor the oxygen concentration inside the housing in real time. A high-purity oxygen inlet 7 is connected to the cathode inlet of the plate-and-frame electrolytic cell 8 via an oxygen delivery pipeline with a series flow meter, ensuring that the oxygen flow into the cathode chamber is controllable and guaranteeing a safe and stable reaction.

[0037] In this embodiment, a temperature control module is also included. The temperature control module includes a cathode heat exchanger 11, an anode heat exchanger 12, a refrigeration unit 6, and a cathode gas-liquid separator heat exchanger 901. The cathode heat exchanger 11 is connected in series in the pipeline between the cathode process circulation pump 3 and the cathode inlet of the plate and frame electrolytic cell 8. The anode heat exchanger 12 is connected in series in the pipeline between the anode process circulation pump 4 and the anode inlet of the plate and frame electrolytic cell 8. The cathode gas-liquid separator heat exchanger 901 is sleeved on the outside of the cathode gas-liquid separator 9. The refrigeration unit 6 is connected to the cooling water inlets of the cathode heat exchanger 11, the anode heat exchanger 12, and the cathode gas-liquid separator heat exchanger 901 through pipelines. The cooling water outlets of the cathode heat exchanger 11, the anode heat exchanger 12, and the cathode gas-liquid separator heat exchanger 901 are all connected to the cooling water return port of the refrigeration unit 6.

[0038] By adopting the above technical solution, the temperature control module realizes temperature regulation of key parts of the system: the cathode heat exchanger 11 is connected in series in the pipeline between the cathode process circulation pump 3 and the cathode inlet of the plate and frame electrolytic cell 8 to regulate the temperature of the liquid delivered by the cathode process circulation pump 3 to the cathode inlet; the anode heat exchanger 12 is connected in series in the pipeline between the anode process circulation pump 4 and the anode inlet of the plate and frame electrolytic cell 8 to regulate the temperature of the liquid delivered by the anode process circulation pump 4 to the anode inlet; the cathode gas-liquid separator heat exchanger 901 is installed... Temperature control is implemented on the outside of the cathode gas-liquid separator 9 to control the temperature of the material inside the cathode gas-liquid separator 9. The refrigeration unit 6 supplies cooling water to the cooling water inlets of the cathode heat exchanger 11, the anode heat exchanger 12, and the cathode gas-liquid separator heat exchanger 901 through pipelines. After heat exchange, the cooling water flows back from the cooling water outlet of each heat exchanger to the cooling water return port of the refrigeration unit 6, forming a cooling water circulation. This stabilizes the temperature of the cathode liquid inlet, the anode liquid inlet, and the material inside the cathode gas-liquid separator 9 within a suitable range, ensuring the efficient electrolysis reaction.

[0039] In this embodiment, the fluid processing module further includes a hydrogen peroxide internal / external circulation switching valve 201, a hydrogen peroxide internal circulation valve 202, a cathode gas-liquid separator ultrapure water supply valve 2071, and an anode gas-liquid separator ultrapure water supply valve 2072. One end of the hydrogen peroxide internal / external circulation switching valve 201 is connected to the bottom outlet of the cathode gas-liquid separator 9, and the other end is connected to the hydrogen peroxide internal circulation valve 202 and the product outlet valve 203 respectively. The end of the hydrogen peroxide internal circulation valve 202 away from the hydrogen peroxide internal / external circulation switching valve 201 is connected to the top inlet of the cathode gas-liquid separator 9. The end of the product outlet valve 203 away from the hydrogen peroxide internal / external circulation switching valve 201 is connected to the product collection tank 13. The cathode gas-liquid separator ultrapure water supply valve 2071 is connected in series in the pipeline between the pure water inlet 14 and the cathode gas-liquid separator 9. The anode gas-liquid separator ultrapure water supply valve 2072 is connected in series in the pipeline between the pure water inlet 14 and the anode gas-liquid separator 10.

[0040] By adopting the above technical solution, one end of the hydrogen peroxide internal / external circulation switching valve 201 is connected to the bottom outlet of the cathode gas-liquid separator 9, and the other end is connected to the hydrogen peroxide internal circulation valve 202 and the product outlet valve 203. When the hydrogen peroxide concentration in the cathode gas-liquid separator 9 does not meet the standard, the hydrogen peroxide internal / external circulation switching valve 201 is connected to the hydrogen peroxide internal circulation valve 202, the product outlet valve 203 is closed, and the other end of the hydrogen peroxide internal circulation valve 202 is connected to the top inlet of the cathode gas-liquid separator 9, so that the liquid flows back to the cathode gas-liquid separator 9 for further concentration; when the concentration meets the standard, the hydrogen peroxide internal / external circulation switching valve 201 and the product outlet valve 203 are connected. The hydrogen peroxide internal circulation valve 202 is closed, and the other end of the product outlet valve 203 is connected to the product collection box 13 to transport the product to the product collection box 13. The cathode gas-liquid separator ultrapure water supply valve 2071 is connected in series in the pipeline between the pure water inlet 14 and the cathode gas-liquid separator 9 to control the supply of ultrapure water to the cathode gas-liquid separator 9. The anode gas-liquid separator ultrapure water supply valve 2072 is connected in series in the pipeline between the pure water inlet 14 and the anode gas-liquid separator 10 to control the supply of ultrapure water to the anode gas-liquid separator 10, so as to ensure the stability of the liquid level and material concentration in the cathode gas-liquid separator 9 and the anode gas-liquid separator 10.

[0041] In this embodiment, the alkali tank level sensor 101, the cathode gas-liquid separator level sensor 102, and the anode gas-liquid separator level sensor 103 are all capacitive sensors and are installed vertically along the corresponding container sidewalls; the electrolytic cell cathode inlet temperature sensor 104, the electrolytic cell cathode outlet temperature transmitter 1041, the electrolytic cell anode inlet temperature sensor 105, the electrolytic cell anode outlet temperature sensor 106, the cathode gas-liquid separator temperature sensor 107, and the anode gas-liquid separator temperature sensor 108 are all PT100 resistance thermometers and are inserted into the corresponding pipes or container walls; the electrolytic cell cathode inlet pressure sensor 1042 and the anode gas-liquid separator pressure sensor 110 are both piezoelectric sensors.

[0042] By adopting the above technical solution, the alkali tank level sensor 101 is a capacitive sensor, vertically installed along the side wall of the alkali tank 2; the cathode gas-liquid separator level sensor 102 is a capacitive sensor, vertically installed along the side wall of the cathode gas-liquid separator 9; and the anode gas-liquid separator level sensor 103 is a capacitive sensor, vertically installed along the side wall of the anode gas-liquid separator 10. Vertical installation ensures that the level detection range covers the effective height of the container. The electrolytic cell cathode inlet temperature sensor 104 is a PT100 resistance thermometer, inserted into the cathode inlet pipe of the plate-and-frame electrolytic cell 8; the electrolytic cell cathode outlet temperature transmitter 1041 is a PT100 resistance thermometer, inserted into the cathode outlet pipe of the plate-and-frame electrolytic cell 8; and the electrolytic cell anode inlet temperature sensor 105 is a P… The T100 RTD is inserted into the anode inlet pipe of the plate-and-frame electrolytic cell 8. The anode outlet temperature sensor 106 is a PT100 RTD inserted into the anode outlet pipe of the plate-and-frame electrolytic cell 8. The cathode gas-liquid separator temperature sensor 107 is a PT100 RTD inserted into the wall of the cathode gas-liquid separator 9. The anode gas-liquid separator temperature sensor 108 is a PT100 RTD inserted into the wall of the anode gas-liquid separator 10. The insertion installation ensures that the temperature detection is close to the actual temperature of the material. The cathode inlet pressure sensor 1042 and the anode gas-liquid separator pressure sensor 110 are piezoelectric sensors. The piezoelectric type ensures rapid pressure detection response and high accuracy, providing accurate data for system parameter control.

[0043] In this embodiment, the first oxygen emergency shut-off valve 401 and the second oxygen emergency shut-off valve 402 are both electromagnetically driven butterfly valves, and the nitrogen shut-off valve 404 is a normally closed solenoid valve; the cathode gas-liquid separator safety valve 405 and the anode gas-liquid separator safety valve 406 are both spring-loaded safety valves, with the opening pressure of the cathode gas-liquid separator safety valve 405 being 1.2 MPa and the opening pressure of the anode gas-liquid separator safety valve 406 being 1.2 MPa.

[0044] By adopting the above technical solutions, the types and parameters of key valves in the safety module are clearly defined to ensure the safety protection effect: the first oxygen emergency shut-off valve 401 and the second oxygen emergency shut-off valve 402 are both electromagnetically driven butterfly valves. The electromagnetic drive method has a fast response speed and can quickly shut off the gas passage in an emergency. The butterfly valve structure is convenient for controlling large flow of gas. The nitrogen shut-off valve 404 is a normally closed solenoid valve. The normally closed state can prevent nitrogen leakage during non-purging periods. The solenoid valve control is convenient for automated operation. The cathode gas-liquid separator safety valve 405 and the anode gas-liquid separator safety valve 406 are both spring-loaded safety valves. The spring structure relies on the spring force to achieve sealing. When the pressure inside the separator exceeds the set value, the spring is compressed, the valve opens to release pressure, and the starting pressure of both is set to 1.2MPa to ensure that the pressure inside the cathode gas-liquid separator 9 and the anode gas-liquid separator 10 does not exceed the safety threshold and avoids safety accidents caused by excessive pressure.

[0045] In this embodiment, the temperature control module further includes a cathode heat exchanger cooling water valve 204, an anode heat exchanger cooling water valve 205, and a cathode gas-liquid separator heat exchanger cooling water valve 208. The cathode heat exchanger cooling water valve 204 is connected in series in the pipeline between the refrigeration unit 6 and the cooling water inlet of the cathode heat exchanger 11. The anode heat exchanger cooling water valve 205 is connected in series in the pipeline between the refrigeration unit 6 and the cooling water inlet of the anode heat exchanger 12. The cathode gas-liquid separator heat exchanger cooling water valve 208 is connected in series in the pipeline between the refrigeration unit 6 and the cooling water inlet of the cathode gas-liquid separator heat exchanger 901. Both the cathode heat exchanger 11 and the anode heat exchanger 12 are plate heat exchangers.

[0046] By adopting the above technical solution, the cathode heat exchanger cooling water valve 204 is connected in series in the pipeline between the chiller unit 6 and the cooling water inlet of the cathode heat exchanger 11. By adjusting the valve opening, the flow rate of cooling water entering the cathode heat exchanger 11 is controlled, thereby regulating the cathode inlet temperature. The anode heat exchanger cooling water valve 205 is connected in series in the pipeline between the chiller unit 6 and the cooling water inlet of the anode heat exchanger 12. By adjusting the valve opening, the flow rate of cooling water entering the anode heat exchanger 12 is controlled, thereby regulating the anode inlet temperature. The cathode gas-liquid separator heat exchanger cooling water valve 208 is connected in series in the pipeline between the chiller unit 6 and the cooling water inlet of the cathode gas-liquid separator heat exchanger 901. By adjusting the valve opening, the flow rate of cooling water entering the cathode gas-liquid separator heat exchanger 901 is controlled, thereby regulating the temperature inside the cathode gas-liquid separator 901. Both the cathode heat exchanger 11 and the anode heat exchanger 12 are plate heat exchangers. Plate heat exchangers have the characteristics of large heat exchange area, high heat transfer efficiency, and compact structure, which can efficiently regulate the temperature of the circulating liquid and ensure the stability of the system temperature.

[0047] This embodiment also provides a system for the electrochemical synthesis of hydrogen peroxide, which uses a PLC controller 300 and the above-mentioned device. The PLC controller 300 is electrically connected to the fluid processing module, reaction module, detection module, safety module and temperature control module respectively.

[0048] By adopting the above technical solution, the system achieves automated control through the PLC controller 300: the PLC controller 300 is electrically connected to the fluid processing module, which can control the operation and action of components such as the alkali tank 2, cathode process circulation pump 3, anode process circulation pump 4, anode alkali replenishment pump 5, and hydrogen peroxide internal / external circulation switching valve 201; it is electrically connected to the reaction module, which can monitor the operating status of the plate and frame electrolyzer 8, cathode gas-liquid separator 9, and anode gas-liquid separator 10; it is electrically connected to the detection module, which can receive detection data from various sensors such as the alkali tank level sensor 101 and the electrochemical trace hydrogen analyzer 111; it is electrically connected to the safety module, which can control the action of valves such as the first oxygen emergency shut-off valve 401 and the nitrogen shut-off valve 404 and receive signals from the oxygen detector 407; and it is electrically connected to the temperature control module, which can control the operation of components such as the refrigeration unit 6 and the cathode heat exchanger cooling water valve 204, thereby realizing the coordinated control of all modules of the entire device, improving the system's automation level and operational stability.

[0049] This embodiment also provides a method for preparing hydrogen peroxide by electrochemical synthesis, which uses the above-mentioned system for preparing hydrogen peroxide by electrochemical synthesis and specifically includes the following steps: S1: System initialization and lazy purging: The PLC controller 300 sends a command to open the nitrogen shut-off valve 404, allowing high-purity nitrogen gas with a purity ≥99.99% to enter the high-purity nitrogen source inlet 403, and controlling the nitrogen pressure to stabilize at 0.4MPa. The high-purity nitrogen gas then enters the cathode gas-liquid separator 9, the anode gas-liquid separator 10, and the anode and cathode pipelines of the plate and frame electrolytic cell 8 to purge the entire system for 5 minutes to replace residual air and eliminate the risk of explosion from the mixing of oxygen and air. During the purging process, the PLC controller 300 monitors the pressure data of the cathode gas-liquid separator pressure sensor 109 and the anode gas-liquid separator pressure sensor 110 in real time to ensure that the system pressure does not exceed 0.6MPa. After the purging is completed, the nitrogen shut-off valve 404 is closed.

[0050] S2: Graded material supply and parameter calibration: S2.1 Ultrapure Water Supply: The PLC controller 300 opens the ultrapure water supply valve 2071 of the cathode gas-liquid separator and the ultrapure water supply valve 2072 of the anode gas-liquid separator, allowing ultrapure water to be injected into the cathode gas-liquid separator 9 and the anode gas-liquid separator 10 through the pure water inlet 14 respectively; the ultrapure water injection flow rate is controlled to be 5-10 L / h, and the liquid level is fed back in real time through the liquid level sensor 102 of the cathode gas-liquid separator and the liquid level sensor 103 of the anode gas-liquid separator. When the liquid level reaches 50% of the total volume of the container, the above two supply valves are closed; S2.2 Alkali replenishment: PLC controller 300 starts anode alkali replenishment pump 5 to inject 30wt% sodium hydroxide solution from alkali tank 2 into anode gas-liquid separator 10, controlling the injection flow rate to 0.1~0.2L / min. The remaining liquid level in alkali tank 2 is monitored by alkali tank level sensor 101. When the liquid level in anode gas-liquid separator 10 stabilizes at 50%, anode alkali replenishment pump 5 is turned off. S2.3 Oxygen Supply: The PLC controller 300 opens the gas supply valve of the high-purity oxygen inlet 7, and introduces oxygen with a purity of 90% to 95% into the cathode chamber of the plate and frame electrolytic cell 8. The oxygen flow rate is controlled at 3 to 6 L / min. The oxygen purity is calibrated in real time by the micro oxygen sensor 112 to ensure that the oxygen purity entering the cathode chamber is not lower than 90%.

[0051] S3: Constant Temperature and Pressure Electrolysis Reaction and Dynamic Control: S3.1 Circulation System Start-up: PLC controller 300 starts the cathode process circulation pump 3 and the anode process circulation pump 4, controls the flow rate of cathode process circulation pump 3 to 0.05~0.2L / min, and transports the liquid in the cathode gas-liquid separator 9 to the cathode heat exchanger 11; controls the flow rate of anode process circulation pump 4 to 0.05~0.2L / min, and transports the liquid in the anode gas-liquid separator 10 to the anode heat exchanger 12; S3.2 Temperature Control Linkage: The PLC controller 300 starts the valves of the refrigeration unit 6 and the temperature control module. Based on the detection data of the cathode liquid inlet temperature sensor 104 and the anode liquid inlet temperature sensor 105 of the electrolytic cell, the opening degree of the cathode heat exchanger cooling water valve 204, the anode heat exchanger cooling water valve 205 and the cathode gas-liquid separator heat exchanger cooling water valve 208 are dynamically adjusted through the PID algorithm to maintain the cathode liquid inlet temperature and the anode liquid inlet temperature at 10±0.5℃. The temperature inside the cathode gas-liquid separator 9 is monitored by the cathode gas-liquid separator temperature sensor 107 to ensure that it does not exceed 12℃. S3.3 Electrolysis Start-up and Parameter Maintenance: Apply a DC voltage of 20-40V to the plate and frame electrolytic cell 8, and adjust the current output through the PLC controller 300 to maintain a current density of 100-300mA / cm². 2 During electrolysis, the inlet pressure is monitored in real time by the cathode inlet pressure sensor 1042 and the anode inlet pressure sensor 1051. When the pressure is >0.6MPa, the corresponding circulation pump speed is reduced by 10% to 15%, and when the pressure is <0.3MPa, the corresponding circulation pump speed is increased by 10% to 15% to ensure that the pressure is stable at 0.3-0.6MPa. S3.4 Electrode reaction: Oxygen reduction reaction occurs in the cathode chamber of plate and frame electrolytic cell 8: O2 + 2H+ + +2e -→H₂O₂, producing a gas-liquid mixture containing hydrogen peroxide; oxygen evolution reaction occurs in the anode chamber: 4OH⁻ - →O2↑+2H2O+4e - This produces an oxygen-containing gas-liquid mixture.

[0052] S4: Gas-liquid separation, product collection and resource recycling: S4.1 Gas-liquid separation: The gas-liquid mixture containing hydrogen peroxide enters the cathode gas-liquid separator 9 from the cathode outlet of the plate and frame electrolyzer 8. After separation by the internal baffles, the liquid collects at the bottom of the separator and flows back to the inlet of the cathode process circulation pump 3. The separated gas is transported through the top pipeline of the cathode gas-liquid separator 9. Along the way, the hydrogen concentration is detected by the electrochemical trace hydrogen analyzer 111. If the hydrogen concentration is ≤1000ppm, the gas is returned to the cathode chamber of the plate and frame electrolyzer 8. If the hydrogen concentration is >1000ppm, the PLC controller 300 triggers an audible and visual alarm. If the concentration is >2000ppm, the electrolysis power supply is immediately cut off and the nitrogen purging program is restarted. The oxygen-containing gas-liquid mixture enters the anode gas-liquid separator 10 from the anode outlet of the plate and frame electrolytic cell 8. After being separated by the internal baffles, the liquid collects at the bottom of the separator and flows back to the inlet of the anode process circulation pump 4. The separated gas is transported through the circulation pipeline at the top of the anode gas-liquid separator 10. The oxygen purity is detected by the micro oxygen sensor 112. When the purity is >85%, the PLC controller 300 opens the oxygen circulation valve 113 to return the gas to the cathode chamber of the plate and frame electrolytic cell 8 to improve the oxygen utilization rate. When the purity is ≤85%, the first oxygen emergency shut-off valve 401 or the second oxygen emergency shut-off valve 402 is opened to allow the gas to be discharged through the oxygen vent 421. S4.2 Product Collection: The PLC controller 300 determines the hydrogen peroxide concentration in the cathode gas-liquid separator 9 by deducing logic based on the electrolysis time and circulating liquid concentration. When the concentration reaches 1% to 3%, the PLC controller 300 controls the hydrogen peroxide internal / external circulation switching valve 201 to switch to connect with the product outlet valve 203, allowing the hydrogen peroxide solution to enter the product collection tank 13. When the concentration does not meet the standard, the hydrogen peroxide internal / external circulation switching valve 201 remains connected with the hydrogen peroxide internal circulation valve 202, and the liquid flows back to the inside of the cathode gas-liquid separator 9, and is then output to the plate and frame electrolyzer 8 via the cathode process circulation pump 3 for further concentration. S4.3 Safety and Liquid Level Control: During the process, if the oxygen detector 407 detects that the oxygen concentration in the movable modular housing 1 is >23%, the PLC controller 300 immediately closes the first oxygen emergency shut-off valve 401 and the second oxygen emergency shut-off valve 402, and opens the nitrogen shut-off valve 404 for inertial purging; if the cathode gas-liquid separator liquid level sensor 102 detects that the liquid level is <20%, the cathode gas-liquid separator ultrapure water supply valve 2071 is automatically opened, and is closed after the liquid level is restored to 50%.

[0053] By adopting the above technical solution, this preparation method relies on the above system to achieve standardized and automated electrochemical synthesis of hydrogen peroxide: In step S1, the high-purity nitrogen source inlet 403 and nitrogen shut-off valve 404 are controlled by PLC controller 300 to purge the system, and the pressure is monitored by cathode gas-liquid separator pressure sensor 109 and anode gas-liquid separator pressure sensor 110 to eliminate safety hazards; In step S2, the ultrapure water supply valve 2071 of cathode gas-liquid separator, ultrapure water supply valve 2072 of anode gas-liquid separator, anode alkali replenishment pump 5, and high-purity oxygen inlet 7 are controlled by PLC controller 300, and the liquid level sensor and trace oxygen sensor 112 are used to realize material... The process involves graded supply and parameter calibration. In step S3, the PLC controller 300 controls the cathode process circulation pump 3, the anode process circulation pump 4, the refrigeration unit 6, and the temperature control valves. Combined with temperature and pressure sensors and PID algorithms, constant temperature and pressure electrolysis is achieved, and specific electrode reactions occur simultaneously. In step S4, gas-liquid separation is performed through the baffles of the cathode gas-liquid separator 9 and the anode gas-liquid separator 10. Combined with the electrochemical trace hydrogen analyzer 111 and the trace oxygen sensor 112, the gas flow direction is controlled. The product collection or reflux is controlled by the hydrogen peroxide internal / external circulation switching valve 201. Safety and liquid level replenishment are achieved through the oxygen detector 407 and the liquid level sensor, ultimately producing hydrogen peroxide efficiently and safely.

[0054] All parts not described in this invention are the same as or can be implemented using existing technology. Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An apparatus for the electrochemical synthesis of hydrogen peroxide, characterized in that, Includes a movable modular housing (1), a fluid handling module, and a reaction module; The fluid processing module is located inside the movable modular housing (1). The fluid processing module includes an alkali tank (2), a cathode process circulation pump (3), an anode process circulation pump (4), an anode alkali replenishment pump (5), a pure water inlet (14), and a product collection tank (13). The reaction module is located in the middle of the movable modular box (1). The reaction module includes a plate and frame electrolytic cell (8), a cathode gas-liquid separator (9), and an anode gas-liquid separator (10). The cathode outlet of the plate and frame electrolytic cell (8) is connected to the inlet at the top of the cathode gas-liquid separator (9), and the anode outlet of the plate and frame electrolytic cell (8) is connected to the inlet at the top of the anode gas-liquid separator (10). The outlet of the alkali tank (2) is connected to the inlet of the anode gas-liquid separator (10) through the anode alkali replenishment pump (5). The inlet of the cathode process circulation pump (3) is connected to the bottom of the cathode gas-liquid separator (9), and the outlet of the cathode process circulation pump (3) is connected to the cathode inlet of the plate and frame electrolytic cell (8). The inlet of the anode process circulation pump (4) is connected to the bottom of the anode gas-liquid separator (10), and the outlet of the anode process circulation pump (4) is connected to the anode inlet of the plate and frame electrolytic cell (8). The pure water inlet (14) is connected to the cathode gas-liquid separator (9) and the anode gas-liquid separator (10) through pipelines. The product collection box (13) is connected to the outlet of the cathode gas-liquid separator (9). The outlet at the upper end of the anode gas-liquid separator (10) is connected to the cathode inlet of the plate and frame electrolytic cell (8) through a circulation pipeline.

2. The apparatus for electrochemical synthesis of hydrogen peroxide according to claim 1, characterized in that, It also includes a detection module, which includes an alkali tank level sensor (101), a cathode gas-liquid separator level sensor (102), an anode gas-liquid separator level sensor (103), an electrolytic cell cathode inlet temperature sensor (104), an electrolytic cell cathode outlet temperature transmitter (1041), an electrolytic cell cathode inlet pressure sensor (1042), an electrolytic cell anode inlet temperature sensor (105), an electrolytic cell anode inlet pressure sensor (1051), an electrolytic cell anode outlet temperature sensor (106), a cathode gas-liquid separator temperature sensor (107), an anode gas-liquid separator temperature sensor (108), a cathode gas-liquid separator pressure sensor (109), and an anode gas-liquid separator... The pressure sensor (110), the electrochemical trace hydrogen analyzer (111), and the trace oxygen sensor (112) are respectively installed on the inlet and outlet pipelines of the alkaline tank (2), the cathode gas-liquid separator (9), the anode gas-liquid separator (10), and the plate and frame electrolytic cell (8). The electrochemical trace hydrogen analyzer (111) is connected in series to the gas outlet pipeline of the cathode gas-liquid separator (9). The gas outlet pipeline of the cathode gas-liquid separator (9) is connected to the inlet of the cathode of the plate and frame electrolytic cell (8). The trace oxygen sensor (112) is connected in series to the circulation pipeline. An oxygen circulation valve (113) is installed on the circulation pipeline.

3. The apparatus for electrochemical synthesis of hydrogen peroxide according to claim 2, characterized in that, It also includes a safety module, which comprises a first oxygen emergency shut-off valve (401), a second oxygen emergency shut-off valve (402), a high-purity nitrogen source inlet (403), a nitrogen shut-off valve (404), a cathode gas-liquid separator safety valve (405), an anode gas-liquid separator safety valve (406), an oxygen detector (407), and a high-purity oxygen inlet (7). The first oxygen emergency shut-off valve (401) and the second oxygen emergency shut-off valve (402) are connected in parallel to the gas outlet pipeline of the anode gas-liquid separator (10). The outlet of the first oxygen emergency shut-off valve (401) and the outlet of the second oxygen emergency shut-off valve (402) are both connected to... The oxygen vent (421) is connected, and the high-purity nitrogen source inlet (403) is connected to the top of the cathode gas-liquid separator (9) and the anode gas-liquid separator (10) respectively through the nitrogen shut-off valve (404). The cathode gas-liquid separator safety valve (405) and the anode gas-liquid separator safety valve (406) are respectively installed on the top of the cathode gas-liquid separator (9) and the anode gas-liquid separator (10). The oxygen detector (407) is installed at the bottom of the movable modular box (1). The high-purity oxygen inlet (7) is connected to the inlet of the cathode of the plate and frame electrolytic cell (8) through the oxygen supply pipeline. A flow meter is connected in series on the oxygen supply pipeline.

4. The apparatus for electrochemical synthesis of hydrogen peroxide according to claim 3, characterized in that, It also includes a temperature control module, which comprises a cathode heat exchanger (11), an anode heat exchanger (12), a refrigeration unit (6), and a cathode gas-liquid separator heat exchanger (901). The cathode heat exchanger (11) is connected in series in the pipeline between the cathode process circulation pump (3) and the cathode inlet of the plate and frame electrolytic cell (8). The anode heat exchanger (12) is connected in series in the pipeline between the anode process circulation pump (4) and the anode inlet of the plate and frame electrolytic cell (8). The cathode gas-liquid separator heat exchanger... The device (901) is fitted outside the cathode gas-liquid separator (9). The refrigeration unit (6) is connected to the cooling water inlet of the cathode heat exchanger (11), the anode heat exchanger (12), and the cathode gas-liquid separator heat exchanger (901) through pipelines. The cooling water outlet of the cathode heat exchanger (11), the cooling water outlet of the anode heat exchanger (12), and the cooling water outlet of the cathode gas-liquid separator heat exchanger (901) are all connected to the cooling water return port of the refrigeration unit (6).

5. The apparatus for electrochemical synthesis of hydrogen peroxide according to claim 4, characterized in that, The fluid processing module also includes a hydrogen peroxide internal / external circulation switching valve (201), a hydrogen peroxide internal circulation valve (202), a cathode gas-liquid separator ultrapure water supply valve (2071), and an anode gas-liquid separator ultrapure water supply valve (2072). One end of the hydrogen peroxide internal / external circulation switching valve (201) is connected to the bottom outlet of the cathode gas-liquid separator (9), and the other end is connected to the hydrogen peroxide internal circulation valve (202) and the product outlet valve (203) respectively. The hydrogen peroxide internal circulation valve (202) is located away from the hydrogen peroxide internal / external circulation switching valve. One end of the switching valve (201) is connected to the top inlet of the cathode gas-liquid separator (9), and the end of the product outlet valve (203) away from the hydrogen peroxide internal / external circulation switching valve (201) is connected to the product collection box (13). The cathode gas-liquid separator ultrapure water supply valve (2071) is connected in series in the pipeline between the pure water inlet (14) and the cathode gas-liquid separator (9). The anode gas-liquid separator ultrapure water supply valve (2072) is connected in series in the pipeline between the pure water inlet (14) and the anode gas-liquid separator (10).

6. The apparatus for electrochemical synthesis of hydrogen peroxide according to claim 5, characterized in that, The alkali tank level sensor (101), the cathode gas-liquid separator level sensor (102), and the anode gas-liquid separator level sensor (103) are all capacitive sensors and are installed vertically along the corresponding container sidewalls; the electrolytic cell cathode inlet temperature sensor (104), the electrolytic cell cathode outlet temperature transmitter (1041), the electrolytic cell anode inlet temperature sensor (105), the electrolytic cell anode outlet temperature sensor (106), the cathode gas-liquid separator temperature sensor (107), and the anode gas-liquid separator temperature sensor (108) are all PT100 resistance thermometers and are inserted into the corresponding pipes or container walls; the electrolytic cell cathode inlet pressure sensor (1042) and the anode gas-liquid separator pressure sensor (110) are both piezoelectric sensors.

7. The apparatus for electrochemical synthesis of hydrogen peroxide according to claim 3, characterized in that, The first oxygen emergency shut-off valve (401) and the second oxygen emergency shut-off valve (402) are both electromagnetically driven butterfly valves, and the nitrogen shut-off valve (404) is a normally closed solenoid valve; the cathode gas-liquid separator safety valve (405) and the anode gas-liquid separator safety valve (406) are both spring-loaded safety valves, the opening pressure of the cathode gas-liquid separator safety valve (405) is 1.2 MPa, and the opening pressure of the anode gas-liquid separator safety valve (406) is 1.2 MPa.

8. The apparatus for electrochemical synthesis of hydrogen peroxide according to claim 6, characterized in that, The temperature control module also includes a cathode heat exchanger cooling water valve (204), an anode heat exchanger cooling water valve (205), and a cathode gas-liquid separator heat exchanger cooling water valve (208). The cathode heat exchanger cooling water valve (204) is connected in series in the pipeline between the refrigeration unit (6) and the cooling water inlet of the cathode heat exchanger (11). The anode heat exchanger cooling water valve (205) is connected in series in the pipeline between the refrigeration unit (6) and the cooling water inlet of the anode heat exchanger (12). The cathode gas-liquid separator heat exchanger cooling water valve (208) is connected in series in the pipeline between the refrigeration unit (6) and the cooling water inlet of the cathode gas-liquid separator heat exchanger (901). The cathode heat exchanger (11) and the anode heat exchanger (12) are both plate heat exchangers.

9. A system for the electrochemical synthesis of hydrogen peroxide, characterized in that, The device includes a PLC controller (300) and an electrochemical synthesis apparatus for hydrogen peroxide as described in any one of claims 1-8, wherein the PLC controller (300) is electrically connected to the fluid processing module, the reaction module, the detection module, the safety module, and the temperature control module, respectively.

10. A method for preparing hydrogen peroxide by electrochemical synthesis, characterized in that, The preparation of hydrogen peroxide using the electrochemical synthesis system described in claim 9 specifically includes the following steps: S1: System initialization and lazy purging: The PLC controller (300) sends a command to open the nitrogen shut-off valve (404), allowing high-purity nitrogen with a purity ≥99.99% to enter the high-purity nitrogen source inlet (403), and controlling the nitrogen pressure to stabilize at 0.4MPa. The high-purity nitrogen enters the cathode gas-liquid separator (9), the anode gas-liquid separator (10), and the anode and cathode pipelines of the plate and frame electrolytic cell (8) to purge the entire system for 5 minutes to replace residual air and eliminate the risk of explosion from the mixing of oxygen and air. During the purging process, the PLC controller (300) monitors the data of the cathode gas-liquid separator pressure sensor (109) and the anode gas-liquid separator pressure sensor (110) in real time to ensure that the system pressure does not exceed 0.6MPa. After the purging is completed, the nitrogen shut-off valve (404) is closed. S2: Graded material supply and parameter calibration: S2.1 Ultrapure water supply: The PLC controller (300) opens the ultrapure water supply valve (2071) of the cathode gas-liquid separator and the ultrapure water supply valve (2072) of the anode gas-liquid separator, so that ultrapure water is injected into the cathode gas-liquid separator (9) and the anode gas-liquid separator (10) through the pure water inlet (14); the ultrapure water injection flow rate is controlled to be 5-10 L / h, and the liquid level is fed back in real time through the liquid level sensor (102) of the cathode gas-liquid separator and the liquid level sensor (103) of the anode gas-liquid separator. When the liquid level reaches 50% of the total volume of the container, the two supply valves are closed. S2.2 Alkali replenishment: The PLC controller (300) starts the anode alkali replenishment pump (5) to inject 30wt% sodium hydroxide solution from the alkali tank (2) into the anode gas-liquid separator (10), controlling the injection flow rate to be 0.1~0.2L / min. The remaining liquid level in the alkali tank (2) is monitored by the alkali tank level sensor (101). When the liquid level in the anode gas-liquid separator (10) is stable at 50%, the anode alkali replenishment pump (5) is turned off. S2.3 Oxygen Supply: The PLC controller (300) opens the gas supply valve of the high-purity oxygen inlet (7) and introduces oxygen with a purity of 90% to 95% into the cathode chamber of the plate and frame electrolytic cell (8). The oxygen flow rate is controlled to be 3 to 6 L / min. The oxygen purity is calibrated in real time by the micro oxygen sensor (112) to ensure that the oxygen purity entering the cathode chamber is not less than 90%. S3: Constant Temperature and Pressure Electrolysis Reaction and Dynamic Control: S3.1 Circulation System Start-up: The PLC controller (300) starts the cathode process circulation pump (3) and the anode process circulation pump (4), controls the flow rate of the cathode process circulation pump (3) to be 0.05~0.2L / min, and transports the liquid in the cathode gas-liquid separator (9) to the cathode heat exchanger (11); controls the flow rate of the anode process circulation pump (4) to be 0.05~0.2L / min, and transports the liquid in the anode gas-liquid separator (10) to the anode heat exchanger (12). S3.2 Temperature control linkage: The PLC controller (300) starts the valves of the refrigeration unit (6) and the temperature control module. Based on the detection data of the cathode liquid inlet temperature sensor (104) and the anode liquid inlet temperature sensor (105) of the electrolytic cell, the opening degree of the cathode heat exchanger cooling water valve (204), the anode heat exchanger cooling water valve (205) and the cathode gas-liquid separator heat exchanger cooling water valve (208) are dynamically adjusted through the PID algorithm to maintain the cathode liquid inlet temperature and the anode liquid inlet temperature at 10±0.5℃. The temperature inside the cathode gas-liquid separator (9) is monitored by the cathode gas-liquid separator temperature sensor (107) to ensure that it does not exceed 12℃. S3.3 Electrolysis Start-up and Parameter Maintenance: Apply a DC voltage of 20-40V to the plate and frame electrolytic cell (8), and adjust the current output through the PLC controller (300) to maintain the current density at 100-300mA / cm². 2 During electrolysis, the inlet pressure is monitored in real time by the cathode inlet pressure sensor (1042) and the anode inlet pressure sensor (1051). When the pressure is >0.6MPa, the corresponding circulation pump speed is reduced by 10% to 15%, and when the pressure is <0.3MPa, the corresponding circulation pump speed is increased by 10% to 15% to ensure that the pressure is stable at 0.3-0.6MPa. S3.4 Electrode reaction: Oxygen reduction reaction occurs in the cathode chamber of the plate and frame electrolytic cell (8): O2 + 2H + +2e - →H₂O₂, producing a gas-liquid mixture containing hydrogen peroxide; oxygen evolution reaction occurs in the anode chamber: 4OH⁻ - →O2↑+2H2O+4e - This produces an oxygen-containing gas-liquid mixture; S4: Gas-liquid separation, product collection and resource recycling: S4.1 Gas-liquid separation: The gas-liquid mixture containing hydrogen peroxide enters the cathode gas-liquid separator (9) from the cathode outlet of the plate and frame electrolyzer (8). After being separated by the internal baffle plate, the liquid is collected at the bottom of the separator and flows back to the inlet of the cathode process circulation pump (3). The separated gas is transported through the top pipeline of the cathode gas-liquid separator (9). Along the way, the hydrogen concentration is detected by the electrochemical trace hydrogen analyzer (111). If the hydrogen concentration is ≤1000ppm, the gas is returned to the cathode chamber of the plate and frame electrolyzer (8). If the hydrogen concentration is >1000ppm, the PLC controller (300) triggers an audible and visual alarm. If the concentration is >2000ppm, the electrolysis power supply is immediately cut off and the nitrogen purging program is restarted. The oxygen-containing gas-liquid mixture enters the anode gas-liquid separator (10) from the anode outlet of the plate and frame electrolytic cell (8). After being separated by the internal baffle plate, the liquid is collected at the bottom of the separator and flows back to the inlet of the anode process circulation pump (4). The separated gas is transported through the circulation pipeline at the top of the anode gas-liquid separator (10). The oxygen purity is detected by the micro oxygen sensor (112). When the purity is >85%, the PLC controller (300) opens the oxygen circulation valve (113) to return the gas to the cathode chamber of the plate and frame electrolytic cell (8) to improve the oxygen utilization rate. When the purity is ≤85%, the first oxygen emergency shut-off valve (401) or the second oxygen emergency shut-off valve (402) is opened to allow the gas to be discharged through the oxygen vent (421). S4.2 Product Collection: The PLC controller (300) determines the hydrogen peroxide concentration in the cathode gas-liquid separator (9) by deducing logic based on the associated electrolysis time and circulating liquid concentration. When the concentration reaches 1% to 3%, the PLC controller (300) controls the hydrogen peroxide internal / external circulation switching valve (201) to switch to be connected with the product outlet valve (203), so that the hydrogen peroxide solution enters the product collection tank (13). When the concentration does not meet the standard, the hydrogen peroxide internal / external circulation switching valve (201) remains connected with the hydrogen peroxide internal circulation valve (202), and the liquid flows back to the inside of the cathode gas-liquid separator (9), and is then output to the plate and frame electrolyzer (8) for further concentration via the cathode process circulation pump (3). S4.3 Safety and Liquid Level Control: During the process, if the oxygen detector (407) detects that the oxygen concentration in the movable modular box (1) is >23%, the PLC controller (300) immediately closes the first oxygen emergency shut-off valve (401) and the second oxygen emergency shut-off valve (402), and opens the nitrogen shut-off valve (404) for inertial purging; if the cathode gas-liquid separator liquid level sensor (102) detects that the liquid level is <20%, the cathode gas-liquid separator ultrapure water supply valve (2071) is automatically opened, and the valve is closed after the liquid level is restored to 50%.

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