Membrane-free chemical-looping cyclic water electrolysis hydrogen production device and method based on intrinsic safety

Abstract

The present invention relates to a membrane-free chemical-looping cyclic water electrolysis hydrogen production device and method based on intrinsic safety. The device comprises two electrolytic cells, a normal-temperature alkali liquor buffer tank, a high-temperature alkali liquor buffer tank, an oxygen separation device, a hydrogen separation device, a storage tank, and an external power supply, wherein at least one electrolytic chamber is formed in each electrolytic cell, an anode plate and a cathode plate are provided in each electrolytic chamber, a porous partition plate is provided between the anode plate and the cathode plate, and the anode plate material contains a chemical-looping oxygen carrier. The method comprises: each electrolytic cell alternately operating in first and second working conditions, and the two electrolytic cells in the same time period being in different working conditions, so as to realize synchronous and continuous production of hydrogen and oxygen in different spaces. The first and the second working conditions are respectively as follows: under the conditions of a normal-temperature alkali liquor and circuit connection, a cathode performs electrochemical hydrogen production, and the chemical-looping oxygen carrier of an anode is oxidized into an oxidized-state chemical-looping oxygen carrier; and under the conditions of a high-temperature alkali liquor and circuit disconnection, the oxidized-state chemical-looping oxygen carrier of the anode is reduced and generates oxygen.

Description

Intrinsically safe membrane-free chemical looping electrolysis water production device and method for hydrogen production Technical Field

[0001] This invention relates to the field of water electrolysis for hydrogen production technology, and in particular to an intrinsically safe membrane-free chemical looping electrolysis water production apparatus and method. Background Technology

[0002] Hydrogen is considered a green energy carrier due to its high energy density and clean properties. However, currently, over 90% of hydrogen is produced from fossil fuels, leading to significant carbon dioxide emissions. To achieve a carbon-free economy, hydrogen production through water electrolysis is crucial, and it can utilize renewable energy sources such as solar, wind, hydro, and geothermal energy to generate electricity. This hydrogen production method not only enables renewable energy storage but also bridges the gaps in the sustainable supply of energy in both time and space.

[0003] Traditional membrane-based water electrolysis for hydrogen production faces challenges such as the safety hazards of hydrogen and oxygen mixing and the high cost of membrane materials. Furthermore, traditional water electrolysis devices must use diaphragms to prevent gas mixing between the anode and cathode, but this method suffers from efficiency losses due to membrane resistance and low capacity, limiting the large-scale application of water electrolysis for hydrogen production. In recent years, research institutions both domestically and internationally have developed over a hundred novel membrane materials; however, due to limitations in the membrane's own ion transport activity and physicochemical stability, membrane-based water electrolysis for hydrogen production still faces the "impossible triangle" problem of safety, large capacity, and high efficiency. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an intrinsically safe membrane-free chemical loop electrolysis water hydrogen production device and method. It employs a chemical loop circulation method to achieve stepwise hydrogen and oxygen production in space and time within a single electrolyzer, thus ensuring intrinsic safety.

[0005] The technical solution adopted in this invention is as follows:

[0006] This invention provides an intrinsically safe membrane-free chemical loop electrolysis water production device, comprising: a first electrolyzer, a second electrolyzer, a room temperature alkaline solution buffer tank, a high temperature alkaline solution buffer tank, an oxygen separation device, a hydrogen separation device, an oxygen storage tank, a hydrogen storage tank, and an external power supply.

[0007] Each electrolytic cell forms at least one electrolytic chamber, which contains an anode plate and a cathode plate. A porous partition is provided between the anode plate and the cathode plate. The anode plate material contains a chemically chained oxygen carrier.

[0008] The first electrolytic cell is connected to the ambient temperature alkaline solution buffer tank via a first automatic pump and to the high temperature alkaline solution buffer tank via a second automatic pump. The product outlet of the first electrolytic cell is connected to the inlet of the oxygen separation device and the hydrogen separation device, respectively.

[0009] The second electrolytic cell is connected to the ambient temperature alkaline solution buffer tank via a fourth automatic pump and to the high temperature alkaline solution buffer tank via a third automatic pump. The product outlet of the second electrolytic cell is connected to the inlet of the oxygen separation device and the hydrogen separation device, respectively.

[0010] The liquid outlet of the oxygen separation device is connected to the ambient temperature alkaline buffer tank and the high temperature alkaline buffer tank respectively, and the gas outlet of the oxygen separation device is connected to the oxygen storage tank.

[0011] The liquid outlet of the hydrogen separation device is connected to the ambient temperature alkaline buffer tank and the high temperature alkaline buffer tank respectively, and the gas outlet of the hydrogen separation device is connected to the hydrogen storage tank through the hydrogen purification device.

[0012] The external power supply is connected to the anode plate and the cathode plate to form a circuit, and the circuit of the first electrolytic cell is controlled by the first power switch and the circuit of the second electrolytic cell is controlled by the second power switch.

[0013] The device is operated by controlling the power switch and the automatic pump, so that each electrolytic cell alternates between the first and second operating conditions, and the two electrolytic cells are in different operating conditions at the same time, so as to realize the synchronous and continuous production of hydrogen and oxygen in different spaces.

[0014] The first operating condition is: under the condition of room temperature alkaline solution and circuit connection, the cathode performs electrochemical hydrogen production, and the chemical chain oxygen carrier at the anode is oxidized to an oxidized chemical chain oxygen carrier.

[0015] The second operating condition is as follows: under the conditions of high temperature alkaline solution and circuit disconnection, the oxidized chemical chain oxygen carrier at the anode is reduced back to the initial chemical chain oxygen carrier by thermochemical means, and oxygen is generated;

[0016] The room-temperature alkaline solution comes from the room-temperature alkaline solution buffer tank, and the high-temperature alkaline solution comes from the high-temperature alkaline solution buffer tank.

[0017] The further technical solution is as follows:

[0018] Within each electrolytic cell, multiple series-connected electrolytic chambers are formed by a plurality of stacked plate assemblies arranged in parallel at intervals; the stacked plate assembly includes the anode plate and the cathode plate, and a nickel plate is provided between the anode plate and the cathode plate of each stacked plate assembly to separate two adjacent electrolytic chambers.

[0019] The chemically chained oxygen carrier is a metal hydroxide.

[0020] In the preparation of the anode plate, the chemically chained oxygen carrier is formed by doping with one or more elements selected from Co, Ba, Ca, Zn, Mg, and Mn to regulate its performance.

[0021] The high-temperature alkaline solution in the high-temperature alkaline solution buffer tank contains a reducing agent.

[0022] The ambient temperature alkaline solution in the ambient temperature alkaline solution buffer tank is 25°C, and the high temperature alkaline solution in the high temperature alkaline solution buffer tank is 60-100°C.

[0023] The alkaline solution in the ambient temperature alkaline solution buffer tank and the high temperature alkaline solution buffer tank is a 10%-30% concentration NaOH solution or KOH solution.

[0024] It also includes an alkali concentration detection device and a pure water storage tank. The alkali concentration detection device is used to detect the concentration of the ambient temperature alkali buffer tank and the high temperature alkali buffer tank. The pure water storage tank is connected to the oxygen separation device and is used to supply water to the device when the alkali concentration exceeds a set value.

[0025] The cathode plate material is one of Pt-based noble metals, Ru-based noble metals, and Ni-based non-noble metals.

[0026] The present invention also provides an intrinsically safe membrane-free chemical looping electrolysis method for hydrogen production based on the aforementioned apparatus, comprising:

[0027] S1. The first automatic pump delivers room temperature alkaline solution to the first electrolytic cell, turns on the first power switch, and the first electrolytic cell operates under the first working condition. The generated hydrogen enters the hydrogen separation device. After separation, the hydrogen is purified by the hydrogen purification device and enters the hydrogen storage tank. The room temperature alkaline solution at the bottom of the hydrogen separation device returns to the room temperature alkaline solution buffer tank. After the hydrogen production limit is reached, the first power switch is turned off, and the first automatic pump draws the room temperature alkaline solution from the first electrolytic cell back to the room temperature alkaline solution buffer tank.

[0028] S2. The second automatic pump delivers the high-temperature alkaline solution to the first electrolytic cell. The first electrolytic cell operates under the second working condition. The generated oxygen is separated by the oxygen separation device and enters the oxygen storage tank. The alkaline solution at the bottom of the oxygen separation device is returned to the high-temperature alkaline solution buffer tank.

[0029] Simultaneously, the fourth automatic pump delivers the room-temperature alkaline solution to the second electrolyzer, turns on the second power switch, and the second electrolyzer operates under the first working condition. The generated hydrogen enters the hydrogen separation device, and after being purified by the hydrogen purification device, it enters the hydrogen storage tank. The room-temperature alkaline solution at the bottom of the hydrogen separation device returns to the room-temperature alkaline solution buffer tank. After the hydrogen production limit is reached, the second power switch is turned off, and the fourth automatic pump draws the room-temperature alkaline solution from the second electrolyzer back to the room-temperature alkaline solution buffer tank. The second automatic pump draws the high-temperature alkaline solution from the first electrolyzer back to the high-temperature alkaline solution buffer tank.

[0030] S3. The first automatic pump delivers the room temperature alkaline solution to the first electrolytic cell, turns on the first power switch, and the first electrolytic cell operates under the first working condition. The generated hydrogen enters the hydrogen separation device. After separation, the hydrogen is purified by the hydrogen purification device and enters the hydrogen storage tank. The room temperature alkaline solution at the bottom of the hydrogen separation device returns to the room temperature alkaline solution buffer tank.

[0031] Meanwhile, the third automatic pump delivers the high-temperature alkaline solution to the second electrolyzer, which operates under the second working condition. The generated oxygen is separated by an oxygen separator and enters the oxygen storage tank. The alkaline solution at the bottom of the oxygen separator is returned to the high-temperature alkaline solution buffer tank. After the hydrogen production limit is reached, the first power switch is turned off, and the first automatic pump draws the room-temperature alkaline solution from the first electrolyzer back to the room-temperature alkaline solution buffer tank. The third automatic pump draws the high-temperature alkaline solution from the second electrolyzer back to the high-temperature alkaline solution buffer tank.

[0032] S4. Repeat S2 to S3.

[0033] The method further includes:

[0034] Regularly check the alkali concentration in the high-temperature alkali buffer tank and the normal-temperature alkali buffer tank. When the alkali concentration is higher than the set value, add water to both alkali buffer tanks.

[0035] The beneficial effects of this invention are as follows:

[0036] 1. This invention employs a chemically chained oxygen carrier circulation system to achieve electrochemical stepwise hydrogen and oxygen evolution, eliminating direct contact between hydrogen and oxygen at the source and ensuring intrinsic safety. This invention achieves synchronous and continuous production of hydrogen and oxygen in different spaces through alternating operation of the electrolyzer under different operating conditions and the coordinated operation of two electrolyzers.

[0037] 2. This invention achieves the recycling of chemically chained oxygen carriers through a combination of electrochemical and thermochemical methods, which can significantly reduce hydrogen production energy consumption compared to using only electrochemical methods.

[0038] 3. This invention improves production efficiency by using series electrolytic cells, while ensuring operability and continuity, providing a reliable technical solution for large-scale industrial applications.

[0039] 4. The device of this invention eliminates the need for traditional diaphragms, effectively avoiding efficiency losses caused by membrane resistance and low capacity caused by membrane specific surface area. Furthermore, this invention only uses porous diaphragms to prevent short circuits between the anode and cathode, without involving the use of expensive membrane materials, thus offering a significant cost advantage.

[0040] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0041] Figure 1 is a schematic diagram of the structure of the device according to an embodiment of the present invention.

[0042] Figure 2 is a schematic diagram of the structure of the electrolytic cell according to an embodiment of the present invention.

[0043] Figure 3 is a schematic diagram of the stacked board assembly according to an embodiment of the present invention.

[0044] In the diagram: 1. First electrolytic cell; 101. Anode plate; 102. Cathode plate; 103. Stacked plate assembly; 1031. Nickel plate; 104. Porous partition; 105. Electrolysis chamber; 11. First automatic pump; 12. Second automatic pump; 2. Second electrolytic cell; 21. Third automatic pump; 22. Fourth automatic pump; 3. Room temperature alkali buffer tank; 4. High temperature alkali buffer tank; 41. Temperature control device; 5. Oxygen separation device; 51. Oxygen storage tank; 6. Hydrogen separation device; 61. Hydrogen purification device; 62. Hydrogen storage tank; 7. Pure water storage tank; 8. External power supply; 81. First power switch; 82. Second power switch. Detailed Implementation

[0045] The specific embodiments of the present invention are described below with reference to the accompanying drawings.

[0046] Example 1

[0047] Referring to Figures 1 and 2, the intrinsically safe membrane-free chemical looping electrolysis water hydrogen production device of this embodiment includes: a first electrolyzer 1, a second electrolyzer 2, a room temperature alkaline solution buffer tank 3, a high temperature alkaline solution buffer tank 4, an oxygen separation device 5, a hydrogen separation device 6, an oxygen storage tank 51, a hydrogen storage tank 62, and an external power supply 8.

[0048] Each electrolytic cell forms at least one electrolytic chamber, which is provided with an anode plate 101 and a cathode plate 102. A porous partition 104 is provided between the anode plate 101 and the cathode plate 102. A chemically chained oxygen carrier is provided on the anode plate 101.

[0049] The first electrolytic cell 1 is connected to the ambient temperature alkaline solution buffer tank 3 via the first automatic pump 11 and to the high temperature alkaline solution buffer tank 4 via the second automatic pump 12. The product outlet of the first electrolytic cell 1 is connected to the inlet of the oxygen separation device 5 and the hydrogen separation device 6, respectively.

[0050] The second electrolytic cell 2 is connected to the ambient temperature alkaline buffer tank 3 via the fourth automatic pump 22 and to the high temperature alkaline buffer tank 4 via the third automatic pump 21. The product outlet of the second electrolytic cell 2 is connected to the inlet of the oxygen separation device 5 and the hydrogen separation device 6, respectively.

[0051] The liquid outlet of the oxygen separation device 5 is connected to the ambient temperature alkaline buffer tank 3 and the high temperature alkaline buffer tank 4 respectively, and the gas outlet of the oxygen separation device 5 is connected to the oxygen storage tank 51.

[0052] The liquid outlet of the hydrogen separation device 6 is connected to the ambient temperature alkaline buffer tank 3 and the high temperature alkaline buffer tank 4 respectively, and the gas outlet of the hydrogen separation device 6 is connected to the hydrogen storage tank 62 through the hydrogen purification device 61.

[0053] An external power supply 8 is connected to the anode plate 101 and the cathode plate 102 to form a circuit. The external power supply 8 controls the circuit on and off of the first electrolytic cell 1 through the first power switch 81 and controls the circuit on and off of the second electrolytic cell 2 through the second power switch 82.

[0054] By controlling the power switch and the automatic pump drive device, each electrolyzer operates alternately in the first and second working conditions, and the two electrolyzers are in different working conditions at the same time, so as to realize the synchronous and continuous production of hydrogen and oxygen in different spaces.

[0055] The first operating condition is: under the conditions of room temperature alkaline solution and circuit connection, the cathode performs electrochemical hydrogen production, and the chemical chain oxygen carrier at the anode is oxidized to an oxidized chemical chain oxygen carrier.

[0056] The second operating condition is as follows: Under the conditions of high temperature alkaline solution and circuit disconnection, the oxidized chemical chain oxygen carrier of the anode is reduced back to the initial chemical chain oxygen carrier in the high temperature alkaline solution in a thermochemical manner, and oxygen is generated;

[0057] The ambient temperature alkaline solution comes from the ambient temperature alkaline solution buffer tank 3, and the high temperature alkaline solution comes from the high temperature alkaline solution buffer tank 4.

[0058] To further improve production efficiency, in this embodiment, multiple electrolytic chambers are formed in series by multiple parallel and spaced stacked plate assemblies 103 in each electrolytic cell. In this embodiment, these are named electrolytic chambers 105. Referring to Figure 3, the stacked plate assembly 103 includes an anode plate 101 and a cathode plate 102. A nickel plate 1031 is provided between the anode plate 101 and the cathode plate 102 in each stacked plate assembly 103, which is used to separate two adjacent electrolytic chambers 105.

[0059] Referring to Figure 2, the anode plate 101 and cathode plate 102 located on the outermost side of the entire electrolytic cell are used to connect to the external power supply 8. The current is transmitted through the nickel plate 1031, and the electrolytic cells 105 are connected in series. During operation, the electrolyte (alkali solution) enters each electrolytic cell 105 synchronously.

[0060] It is understood that each electrolysis chamber 105 is provided with a porous partition 104, which is located between the anode plate 101 and the cathode plate 102, and can effectively prevent short circuits.

[0061] As a preferred embodiment, the chemically chained oxygen carrier is a metal hydroxide.

[0062] As a preferred embodiment, the anode plate 101 material is composed of nickel foam current collector, chemically chained oxygen carrier Ni(OH)2, polyvinylidene fluoride, acetylene black, and N-methylpyrrolidone, and the preparation method is as follows:

[0063] The chemically chained oxygen carrier can have its performance regulated by doping, creating defects, controlling size, and creating pores. Preferably, during the preparation of the anode plate 101, the chemically chained oxygen carrier is formed after performance regulation by doping with one or more elements selected from Co, Ba, Ca, Zn, Mg, and Mn.

[0064] A certain amount of Ni(OH)₂, polyvinylidene fluoride, acetylene black, and N-methylpyrrolidone solution were mixed to form a slurry; then the slurry was brushed onto cleaned nickel foam, with multiple brushings applied. The mass loading of Ni(OH)₂ was 200 mg / cm³. -2 .

[0065] As a preferred embodiment, the cathode plate 102 is made of one of Pt-based noble metals, Ru-based noble metals, or Ni-based non-noble metals.

[0066] As a specific implementation, the room temperature alkaline solution in the room temperature alkaline solution buffer tank 3 is 25°C, and the high temperature alkaline solution in the high temperature alkaline solution buffer tank 4 is 60-100°C, preferably 90°C.

[0067] As a preferred embodiment, the alkaline solution stored in the ambient temperature alkaline solution buffer tank 3 and the high temperature alkaline solution buffer tank 4 is a 10%-30% concentration NaOH solution or KOH solution.

[0068] As a preferred embodiment, a temperature control device 41 is installed on the front side of the inlet of the high-temperature alkali buffer tank 4, which is used to control the temperature of the alkali entering the high-temperature alkali buffer tank 4.

[0069] To further improve the convenience of automated operation, the device in this embodiment is also equipped with an alkali concentration detection device and a pure water storage tank 7. The alkali concentration detection device is used to detect the concentration of the room temperature alkali buffer tank 3 and the high temperature alkali buffer tank 4. The pure water storage tank 7 is connected to the oxygen separation device 5 and is used to supply water to the device when the alkali concentration exceeds the set value.

[0070] Example 2

[0071] This embodiment provides an intrinsically safe membrane-free chemical looping cycle water electrolysis method for hydrogen production based on the apparatus of Embodiment 1, comprising:

[0072] S1. The first automatic pump 11 delivers room temperature alkaline solution to the first electrolytic cell 1. The first power switch 81 is turned on, and the first electrolytic cell 1 operates under the first working condition. Hydrogen evolution reaction occurs at the cathode to generate hydrogen gas. Ni(OH)2 in the anode plate 101 is oxidized to NiOOH. The generated hydrogen gas enters the hydrogen separation device 6. After separation, the hydrogen gas is purified by the hydrogen purification device 61 and enters the hydrogen storage tank 62. The room temperature alkaline solution at the bottom of the hydrogen separation device 6 is returned to the room temperature alkaline solution buffer tank 3. After the hydrogen production limit is reached, the first power switch 81 is turned off, and the first automatic pump 11 draws the room temperature alkaline solution from the first electrolytic cell 1 back to the room temperature alkaline solution buffer tank 3.

[0073] S2. The second automatic pump 12 delivers the high-temperature alkaline solution to the first electrolytic cell 1. The first electrolytic cell 1 operates under the second working condition. The NiOOH in the anode plate 101 is spontaneously reduced back to Ni(OH)2 in the high-temperature alkaline solution in a thermochemical manner, and oxygen is generated. The generated oxygen is separated by the oxygen separation device 5 and enters the oxygen storage tank 51. The alkaline solution at the bottom of the oxygen separation device 5 is returned to the high-temperature alkaline solution buffer tank 4.

[0074] Simultaneously, the fourth automatic pump 22 delivers the room-temperature alkaline solution to the second electrolytic cell 2, and the second power switch 82 is turned on. The second electrolytic cell 2 operates under the first working condition. Hydrogen evolution reaction occurs at the cathode to generate hydrogen gas. Ni(OH)2 in the anode plate 101 is oxidized to NiOOH. The generated hydrogen gas enters the hydrogen separation device 6. After separation, the hydrogen gas is purified by the hydrogen purification device 61 and then enters the hydrogen storage tank 62. The room-temperature alkaline solution at the bottom of the hydrogen separation device 6 returns to the room-temperature alkaline solution buffer tank 3. After the hydrogen production limit is reached, the second power switch 82 is turned off. The fourth automatic pump 22 draws the room-temperature alkaline solution from the second electrolytic cell 2 back to the room-temperature alkaline solution buffer tank 3. The second automatic pump 12 draws the high-temperature alkaline solution from the first electrolytic cell 1 back to the high-temperature alkaline solution buffer tank 4.

[0075] S3. The first automatic pump 11 delivers the room temperature alkaline solution to the first electrolytic cell 1. The first power switch 81 is turned on, and the first electrolytic cell 1 operates under the first working condition. Hydrogen evolution reaction occurs at the cathode to generate hydrogen gas. Ni(OH)2 in the anode plate 101 is oxidized to NiOOH. The generated hydrogen gas enters the hydrogen separation device 6. After separation, the hydrogen gas is purified by the hydrogen purification device 61 and enters the hydrogen storage tank 62. The room temperature alkaline solution at the bottom of the hydrogen separation device 6 is returned to the room temperature alkaline solution buffer tank 3.

[0076] Meanwhile, the third automatic pump 21 delivers the high-temperature alkaline solution to the second electrolyzer 2. The second electrolyzer 2 operates under the second working condition. The generated oxygen is separated by the oxygen separation device 5 and enters the oxygen storage tank 51. The alkaline solution at the bottom of the oxygen separation device 5 is returned to the high-temperature alkaline solution buffer tank 4. After the hydrogen production limit is reached, the first power switch 81 is turned off. The first automatic pump 11 pumps the room temperature alkaline solution from the first electrolyzer 1 back to the room temperature alkaline solution buffer tank 3, and the third automatic pump 21 pumps the high-temperature alkaline solution from the second electrolyzer 2 back to the high-temperature alkaline solution buffer tank 4.

[0077] S4. Repeat S2 to S3.

[0078] The intrinsically safe membrane-free chemical looping electrolysis method for hydrogen production further includes:

[0079] The concentration of alkali solution in the high-temperature alkali solution buffer tank 4 and the normal-temperature alkali solution buffer tank 3 is checked regularly. When the alkali solution concentration is higher than the set value, water is added to both alkali solution buffer tanks. Specifically, water is added to the oxygen separation device 5 through the pure water storage tank 7 connected to the oxygen separation device 5, and then water is added to the two alkali solution buffer tanks.

[0080] In addition, this embodiment can promote the reduction of the oxidized chemical chain oxygen carrier in the anode plate 101 by adding a reducing agent to the high-temperature alkaline buffer tank 4. The reducing agent includes one of glucose, urea, and reducing wastewater.

[0081] Application Examples:

[0082] According to Embodiment 2, the alkaline solution is a 30% KOH solution.

[0083] The hydrogen production current density used in the first operating condition is 500-4000 A / m 2 The operating time for the first and second operating conditions is 10 minutes to 6 hours, and the specific operating time depends on the content of competitive oxygen evolution during the hydrogen production stage.

[0084] The hydrogen produced under the first operating condition has a purity of not less than 99%. When the hydrogen purity is less than 99%, regardless of whether the chemical chain oxygen carrier is completely oxidized, it is necessary to switch to the second operating condition.

[0085] As a specific implementation method, the first operating condition uses 1000A / m 2 The hydrogen production current density is [not specified], the operating time for the first and second operating conditions is 30 minutes, the average hydrogen production voltage of the electrolysis chamber is 1.68V, and the hydrogen purity is 99.9%.

[0086] It will be understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A membrane-free chemical looping electrolysis water production device based on intrinsic safety, characterized in that, include: The system includes a first electrolytic cell (1), a second electrolytic cell (2), a room temperature alkaline solution buffer tank (3), a high temperature alkaline solution buffer tank (4), an oxygen separation device (5), a hydrogen separation device (6), an oxygen storage tank (51), a hydrogen storage tank (62), and an external power supply (8). Each electrolytic cell forms at least one electrolytic chamber, which is provided with an anode plate (101) and a cathode plate (102). A porous partition (104) is provided between the anode plate (101) and the cathode plate (102). The anode plate (101) is made of a chemically chained oxygen carrier. The first electrolytic cell (1) is connected to the ambient temperature alkaline buffer tank (3) via a first automatic pump (11) and to the high temperature alkaline buffer tank (4) via a second automatic pump (12). The product outlet of the first electrolytic cell (1) is connected to the inlet of the oxygen separation device (5) and the hydrogen separation device (6) respectively. The second electrolytic cell (2) is connected to the ambient temperature alkaline buffer tank (3) via a fourth automatic pump (22) and to the high temperature alkaline buffer tank (4) via a third automatic pump (21). The product outlet of the second electrolytic cell (2) is connected to the inlet of the oxygen separation device (5) and the hydrogen separation device (6) respectively. The liquid outlet of the oxygen separation device (5) is connected to the ambient temperature alkaline buffer tank (3) and the high temperature alkaline buffer tank (4) respectively, and the gas outlet of the oxygen separation device (5) is connected to the oxygen storage tank (51). The liquid outlet of the hydrogen separation device (6) is connected to the ambient temperature alkaline buffer tank (3) and the high temperature alkaline buffer tank (4) respectively, and the gas outlet of the hydrogen separation device (6) is connected to the hydrogen storage tank (62) through the hydrogen purification device (61). The external power supply (8) is connected to the anode plate (101) and the cathode plate (102) to form a circuit, and controls the circuit opening and closing of the first electrolytic cell (1) through the first power switch (81) and the circuit opening and closing of the second electrolytic cell (2) through the second power switch (82); The device is operated by controlling the power switch and the automatic pump, so that each electrolytic cell alternates between the first and second operating conditions, and the two electrolytic cells are in different operating conditions at the same time, so as to realize the synchronous and continuous production of hydrogen and oxygen in different spaces. The first operating condition is: under the conditions of room temperature alkaline solution and circuit connection, the cathode performs electrochemical hydrogen production, and the chemical chain oxygen carrier at the anode is oxidized to an oxidized chemical chain oxygen carrier. The second operating condition is as follows: under the conditions of high temperature alkaline solution and circuit disconnection, the oxidized chemical chain oxygen carrier at the anode is reduced back to the initial chemical chain oxygen carrier by thermochemical means, and oxygen is generated; The ambient temperature alkaline solution comes from the ambient temperature alkaline solution buffer tank (3), and the high temperature alkaline solution comes from the high temperature alkaline solution buffer tank (4).

2. The membrane-free chemical loop electrolysis water production device based on intrinsic safety according to claim 1, characterized in that, Within each electrolytic cell, multiple electrolytic chambers (105) are formed by multiple parallel and spaced stacked plate assemblies (103); each stacked plate assembly (103) includes an anode plate (101) and a cathode plate (102), and a nickel plate (1031) is provided between the anode plate (101) and the cathode plate (102) of each stacked plate assembly (103) to separate two adjacent electrolytic chambers (105).

3. The intrinsically safe membrane-free chemical looping electrolysis water production device for hydrogen production according to claim 1, characterized in that, The chemically chained oxygen carrier is a metal hydroxide.

4. The intrinsically safe membrane-free chemical looping electrolysis water production device for hydrogen production according to claim 3, characterized in that, In the preparation of the anode plate (101), the chemically chained oxygen carrier is formed by doping with one or more elements selected from Co, Ba, Ca, Zn, Mg, and Mn to regulate its performance.

5. The intrinsically safe membrane-free chemical looping electrolysis water production device for hydrogen production according to claim 1, characterized in that, The high-temperature alkaline solution in the high-temperature alkaline solution buffer tank (4) contains a reducing agent.

6. The membrane-free chemical looping electrolysis water production device based on intrinsic safety according to claim 1, characterized in that, The room temperature alkaline solution in the room temperature alkaline solution buffer tank (3) is 25°C, and the high temperature alkaline solution in the high temperature alkaline solution buffer tank (4) is 60-100°C. The alkaline solutions in the ambient temperature alkaline solution buffer tank (3) and the high temperature alkaline solution buffer tank (4) are 10%-30% NaOH or KOH solutions.

7. The membrane-free chemical looping electrolysis water production device based on intrinsic safety according to claim 1, characterized in that, It also includes an alkali concentration detection device and a pure water storage tank (7). The alkali concentration detection device is used to detect the concentration of the ambient temperature alkali buffer tank (3) and the high temperature alkali buffer tank (4). The pure water storage tank (7) is connected to the oxygen separation device (5) and is used to supply water to the device when the alkali concentration exceeds the set value.

8. The membrane-free chemical looping electrolysis water production device based on intrinsic safety according to claim 1, characterized in that, The cathode plate (102) is made of one of the following materials: Pt-based noble metals, Ru-based noble metals, and Ni-based non-noble metals.

9. A membrane-free chemical looping electrolysis method for hydrogen production based on the apparatus according to any one of claims 1-8, characterized in that, include: S1. The first automatic pump (11) delivers room temperature alkaline solution to the first electrolytic cell (1), turns on the first power switch (81), and the first electrolytic cell (1) operates under the first working condition. The generated hydrogen enters the hydrogen separation device (6). After separation, the hydrogen is purified by the hydrogen purification device (61) and enters the hydrogen storage tank (62). The room temperature alkaline solution at the bottom of the hydrogen separation device (6) returns to the room temperature alkaline solution buffer tank (3). After reaching the hydrogen production limit, the first power switch (81) is turned off, and the first automatic pump (11) draws the room temperature alkaline solution from the first electrolytic cell (1) back to the room temperature alkaline solution buffer tank (3). S2, the second automatic pump (12) delivers the high-temperature alkaline solution to the first electrolytic cell (1). The first electrolytic cell (1) operates under the second working condition. The generated oxygen is separated by the oxygen separation device (5) and enters the oxygen storage tank (51). The alkaline solution at the bottom of the oxygen separation device (5) is returned to the high-temperature alkaline solution buffer tank (4). At the same time, the fourth automatic pump (22) delivers the room temperature alkaline solution to the second electrolytic cell (2), turns on the second power switch (82), and the second electrolytic cell (2) operates under the first working condition. The generated hydrogen enters the hydrogen separation device (6). After separation, the hydrogen enters the hydrogen storage tank (62) after being purified by the hydrogen purification device (61). The room temperature alkaline solution at the bottom of the hydrogen separation device (6) returns to the room temperature alkaline solution buffer tank (3). After reaching the hydrogen production limit, the second power switch (82) is turned off, and the fourth automatic pump (22) draws the room temperature alkaline solution from the second electrolytic cell (2) back to the room temperature alkaline solution buffer tank (3). The second automatic pump (12) draws the high temperature alkaline solution from the first electrolytic cell (1) back to the high temperature alkaline solution buffer tank (4). S3. The first automatic pump (11) delivers the room temperature alkaline solution to the first electrolytic cell (1), turns on the first power switch (81), and the first electrolytic cell (1) operates under the first working condition. The generated hydrogen enters the hydrogen separation device (6). After separation, the hydrogen is purified by the hydrogen purification device (61) and enters the hydrogen storage tank (62). The room temperature alkaline solution at the bottom of the hydrogen separation device (6) is returned to the room temperature alkaline solution buffer tank (3). Meanwhile, the third automatic pump (21) delivers the high-temperature alkaline solution to the second electrolytic cell (2). The second electrolytic cell (2) operates under the second working condition. The generated oxygen is separated by the oxygen separation device (5) and enters the oxygen storage tank (51). The alkaline solution at the bottom of the oxygen separation device (5) is returned to the high-temperature alkaline solution buffer tank (4). After the hydrogen production limit is reached, the first power switch (81) is turned off. The first automatic pump (11) draws the room temperature alkaline solution from the first electrolytic cell (1) back to the room temperature alkaline solution buffer tank (3). The third automatic pump (21) draws the high-temperature alkaline solution from the second electrolytic cell (2) back to the high-temperature alkaline solution buffer tank (4). S4. Repeat S2 to S3.

10. The intrinsically safe membrane-free chemical looping electrolysis method for hydrogen production based on claim 9, characterized in that, Also includes: Regularly check the concentration of alkali in the high-temperature alkali buffer tank (4) and the normal-temperature alkali buffer tank (3). When the concentration of alkali is higher than the set value, add water to the two alkali buffer tanks.

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