Method and system for producing hydrogen from air

Abstract

The present invention belongs to the field of electrochemical technology, specifically a method and system for producing hydrogen from air. This method provides energy input through a power supply module, and a hygroscopic medium is placed in an atmospheric environment. Under the action of the pressure difference at the interface between the air and the hygroscopic medium, water molecules are induced to liquefy and absorb by the hygroscopic medium to undergo a first-order phase change migration; at the same time, driven by the pressure difference at the interface between the hygroscopic medium and the electrolyte, the water in the hygroscopic medium undergoes a second-order phase change migration through the water vapor mass transfer layer and enters the electrolyte; at the same time, the hydrophobic effect of the water vapor mass transfer layer effectively blocks the impurities in the hygroscopic medium. During electrolysis, the water in the electrolyte is consumed to produce hydrogen and oxygen, and induces electrolyte regeneration, etc. This system can perform continuous in-situ hydrogen production without being restricted by time and space. At the same time, the system device can be coupled with wind power and photovoltaics to realize energy conversion of non-stable renewable energy, and the hydrogen energy generated is conducive to stable storage.

Description

Technical Field

[0001] The present invention belongs to the field of electrochemical technology and relates to a novel direct air hydrogen production technology driven by multi-stage phase change, specifically an air hydrogen production method and system. Background Art

[0002] Hydrogen energy has the advantages of wide sources, storability, multiple uses, zero carbon and zero pollution, and high energy density. It is a key component of the future energy field.

[0003] There are currently two ways to obtain hydrogen energy through water electrolysis. One is to directly use non-pure aqueous solutions such as seawater, river water or lake water in nature. Taking seawater electrolysis for hydrogen production as an example, there are the following problems: ① The composition of seawater is complex, and its composition varies with factors such as season, climate, temperature, region and human activities. Therefore, direct hydrogen production electrolysis devices from seawater in different regions are not directly compatible; ② Cl in seawater is not directly compatible with the chlorine content of chlorine in seawater. - The highest content, in the electrolysis reaction, Cl - Can be oxidized in the oxygen evolution reaction to produce toxic, environmentally harmful, and corrosive ClO - and Cl2; ③ When hydrogen is produced directly from seawater, H + and OH - The ion concentration is too small or the buffer molecules cannot transport OH at the cathode and anode respectively. - and H + , resulting in low electrolysis efficiency, so additional additives or ion exchange membranes are needed, which greatly increases costs. At the same time, the exchange membrane is highly sensitive to impurities and may have deactivation or maintenance costs; ④ Due to local pH differences during electrolysis, precipitation may occur with calcium and magnesium ions, and acid precipitation treatment is required, which incurs additional costs; ⑤ Seawater resources are geographically limited, and it is difficult for inland areas to directly use seawater resources to produce hydrogen. The second is to purify various non-pure water solutions to produce pure water for use in electrolytic cells. This method requires the establishment of a desalination plant, which greatly increases costs in terms of energy consumption, construction, operation, manpower, maintenance, etc.; at the same time, the transportation and utilization of water resources and hydrogen energy will further increase the cost of laying pipelines.

[0004] Air, as the medium of communication between oceans, lakes, and land, is rich in water molecules. According to statistics, the global atmosphere contains approximately 13 trillion tons of water vapor, making it a highly promising source of water for hydrogen production through water electrolysis. Therefore, the development of an air-to-hydrogen system would avoid the costs and technical challenges associated with hydrogen transportation, thus possessing considerable research value. Summary of the Invention

[0005] The present invention addresses the challenges of the existing technology by providing an air-to-hydrogen system. This system utilizes gas-liquid and liquid-liquid phase equilibria to drive continuous and stable hydrogen production through multi-stage phase transitions of water molecules. This invention fundamentally addresses the issue of water resource limitations in hydrogen production through water electrolysis. It also contributes to the future of hydrogen energy conversion, enabling it to be unconstrained by time and space, while completely avoiding the costs and technical challenges associated with hydrogen transportation.

[0006] Another object of the present invention is to provide a method for producing hydrogen from air using the above system.

[0007] In order to achieve the above object of the invention, the specific technical solution of the present invention is:

[0008] A method for producing hydrogen from air comprises the following steps: a power supply module provides energy input, a hygroscopic medium is placed in an atmospheric environment, and under the action of the interface pressure difference between the air and the hygroscopic medium, water molecules are induced to liquefy and absorb by the hygroscopic medium to undergo a primary phase change migration; simultaneously, driven by the interface pressure difference between the hygroscopic medium and the electrolyte, water in the hygroscopic medium undergoes a secondary phase change migration through a water vapor mass transfer layer and enters the electrolyte; simultaneously, the hydrophobic effect of the water vapor mass transfer layer effectively blocks impurities in the solution, and during electrolysis, water in the electrolyte is consumed to produce hydrogen and oxygen, and induces electrolyte regeneration, further maintaining the interface pressure difference; when the water migrated in the primary phase change and the secondary phase change is equal to the amount of water consumed in hydrogen production by electrolysis, dynamically stable and balanced hydrogen production from air is achieved.

[0009] The specific steps of this method are as follows:

[0010] The power supply module is connected to the cathode plate and the anode plate to provide electrical energy for the hydrogen production reaction; the hygroscopic medium layer is in direct contact with the air. By utilizing the pressure difference between the air and the hygroscopic interface, the hygroscopic medium will induce the liquefaction of water molecules in the air to form a first-order phase change migration;

[0011] At the same time, under the action of the interface pressure difference between the cathode electrolyte layer and the cathode hygroscopic medium layer, and between the anode electrolyte layer and the anode hygroscopic medium layer, the water in the hygroscopic medium layer undergoes secondary migration into the electrolyte layer. The mass transfer layer between the two prevents mutual penetration due to the hydrophobic effect and transmits water vapor molecules through its own porous structure.

[0012] After water molecules enter the electrolyte layer, if the electrolyte is alkaline, a reduction hydrogen evolution reaction will first occur on the surface of the cathode catalyst layer. The reaction formula is as follows:

[0013] 2H2O+2e - →H2+2OH -

[0014] The produced hydrogen passes through a hydrogen scrubber and a hydrogen dryer to remove the water vapor contained in the hydrogen, and is collected through a pipeline into a hydrogen collection bottle for storage and further use.

[0015] The generated OH - It is transferred to the anode catalyst layer through the diaphragm / ion exchange membrane, where an oxidation reaction occurs to produce oxygen; the reaction formula is as follows:

[0016]

[0017] The oxygen generated by the oxygen evolution reaction passes through the oxygen scrubber and oxygen dryer and is collected in an oxygen collection bottle.

[0018] If the electrolyte is acidic, the oxidation and oxygen evolution reaction will first occur on the surface of the anode catalyst layer, and the reaction formula is as follows:

[0019]

[0020] The oxygen generated by the oxygen evolution reaction passes through the oxygen scrubber and oxygen dryer and is collected in an oxygen collection bottle.

[0021] The generated H + It is transferred to the cathode catalyst layer through the diaphragm / ion exchange membrane, where a reduction reaction occurs to produce hydrogen;

[0022] The reaction formula is as follows:

[0023] 2H + +2e - →H2

[0024] The produced hydrogen passes through a hydrogen scrubber and a hydrogen dryer to remove the water vapor contained in the hydrogen, and is collected through a pipeline into a hydrogen collection bottle for storage and further use.

[0025] An air hydrogen production system is used in air hydrogen production processes. The system includes an electrolysis device consisting of an anode chamber, a cathode chamber, and a diaphragm arranged between the anode and cathode chambers, a power supply device, a primary phase change migration device, a secondary phase change migration device, and an electrolytic catalytic hydrogen production device; the power supply device is respectively connected to the cathode plate and the anode plate for providing energy; the secondary phase change migration device and the primary phase change migration device are sequentially arranged on the periphery of the electrolysis device, and the electrolytic catalytic hydrogen production device is arranged inside the electrolysis device.

[0026] As a better implementation method in the present application, the energy source in the power supply device can be renewable energy sources such as solar energy and wind energy converted into electrical energy, or it can directly utilize thermal power, hydropower, etc.

[0027] As a better embodiment of the present application, the secondary phase change migration device includes an anode mass transfer layer, an anode electrolyte layer, a cathode electrolyte layer, and a cathode mass transfer layer; the anode electrolyte layer is laid in the anode chamber, the cathode electrolyte layer is laid in the cathode chamber, the anode mass transfer layer is arranged on the outer layer of the anode electrolyte layer, and the cathode mass transfer layer is arranged on the outer layer of the cathode electrolyte layer.

[0028] As a better embodiment of the present application, the primary phase change migration device includes an anode hygroscopic medium layer and a cathode hygroscopic medium layer, the anode hygroscopic medium layer is connected to the anode mass transfer layer, and the cathode hygroscopic medium layer is connected to the cathode mass transfer layer.

[0029] As a preferred embodiment of the present application, an anode plate is provided in the anode chamber, and a cathode plate is provided in the cathode chamber.

[0030] As a preferred embodiment of the present application, the electrolytic catalytic hydrogen production device includes an anode catalyst layer and a cathode catalyst layer, the anode catalyst layer is connected to the anode plate, and the cathode catalyst layer is connected to the cathode plate.

[0031] As a better embodiment of the present application, the electrolytic catalytic hydrogen production device also includes an oxygen scrubber, an oxygen dryer, an oxygen collecting bottle, a hydrogen scrubber, a hydrogen dryer and a hydrogen collecting bottle; under the action of the anode catalytic layer, the oxygen generated in the anode chamber is passed into the oxygen scrubber and the oxygen dryer connected to the anode chamber in sequence, and finally collected in the oxygen collecting bottle; under the action of the cathode catalytic layer, the hydrogen generated in the cathode chamber is passed into the hydrogen scrubber and the hydrogen dryer connected to the cathode chamber in sequence, and finally collected in the hydrogen collecting bottle.

[0032] As a better embodiment of the present application, the anode mass transfer layer and the cathode mass transfer layer include but are not limited to a waterproof and breathable layer of any one of TPU, PDMS, PTFE with a pore size of 0.1 to 100 um, or a porous waterproof and breathable layer prepared by spraying, screen printing, or electrostatic adsorption of graphene, PVDF particles, PTFE membrane, or PTFE particles.

[0033] As a preferred embodiment of the present application, the hygroscopic medium in the anode hygroscopic medium layer and the cathode hygroscopic medium layer includes but is not limited to hygroscopic gels such as PVA, PAMPS, PAAM, or liquid absorbents such as glycerol, CaSO4, MgSO4, LiBr, CaCl2, CsF, LiCl, etc. with a concentration of 30-100wt%.

[0034] As a better embodiment of the present application, the electrolytes in the anode electrolyte layer and the cathode electrolyte layer include but are not limited to solid gel electrolytes such as PVA, PAMPS, PAAM, or liquid electrolytes such as Na2SO4, K2SO4, K3PO4, K2CO3, NaOH, KOH with a concentration of 30-100wt%.

[0035] As a better embodiment of the present application, the anode catalytic electrode includes but is not limited to FexCoyNiz type catalyst, iridium tantalum, ruthenium iridium, NiFe-LDH, NiFeCu alloy catalyst supported titanium mesh or Mo-Ni3S2, etc.; the hydrogen evolution catalyst includes but is not limited to platinum mesh, nickel-plated platinum mesh or Pt / C.

[0036] Compared with the prior art, the positive effects of the present invention are embodied in:

[0037] (1) The system provides electrical energy through a power supply module, induces water vapor phase change migration through a hygroscopic medium and electrolyte, and then produces hydrogen using the principle of catalytic electrolysis. First, the system can achieve a dynamic and continuous process in the atmospheric environment without time and space differences. Second, the use of two separate solutions as a hygroscopic medium and electrolyte to absorb water molecules from the air and electrolyze water can effectively prevent the solution from reacting with acidic and alkaline media in the air or the solution's own ions from participating in the electrolysis reaction, thereby extending the system's service life and reaction stability. Furthermore, it can achieve energy conversion and stable storage for unstable renewable energy in water-scarce areas such as deserts and inland areas, providing a technical means for the construction of future energy systems. Finally, this technology can compensate for the geographical limitations of hydrogen production by electrolysis of seawater or freshwater, enabling on-site hydrogen production in any region and resolving the cost or technical issues associated with water resources and hydrogen energy transportation.

[0038] (2) The present invention can achieve efficient and stable hydrogen energy conversion under high voltage and high current density.

[0039] (3) The present invention adopts a two-stage phase transition migration strategy, which independently separates the functions of direct contact with air to absorb water and electrolytic hydrogen production, which are independently completed by the hygroscopic medium and electrolyte. On the one hand, this prevents the high-conductivity electrolyte from reacting with gases such as carbon dioxide in the air, which would reduce its own conductivity and affect the electrolysis reaction; it also prevents the ions inherent in the highly hygroscopic electrolyte from participating in the electrolysis reaction. On the other hand, the two-stage phase transition migration of water ensures timely replenishment of water to meet electrolysis consumption.

[0040] (IV) The mass transfer power of the present invention comes from the interfacial pressure difference between the solution and the air, and the migration of water is a spontaneous reaction, which avoids the extra energy consumption of traditional air condensation and pressurization to obtain pure water.

[0041] (5) The ion content of water molecules in the air is extremely low, and the water obtained from the air provides a single pure environment for hydrogen production.

[0042] (6) The present invention breaks through the bottleneck of finding water sources for electrolytic hydrogen storage in traditional arid areas. There is no need to build long-distance water pipelines or carry out long-distance hydrogen transportation, which greatly reduces the costs of construction, operation, manpower, maintenance, etc.

[0043] (7) The present invention can realize on-site hydrogen production, solve the cost and technical problems of hydrogen transportation, and provide technical support for the future layout of on-site hydrogen production and hydrogenation stations, hydrogen fuel power systems and other integrated "hydrogen production-use" construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a structural schematic diagram of an air hydrogen production system according to the present invention;

[0045] Among them, 1-anode hygroscopic medium layer, 2-anode mass transfer layer, 3-anode electrolyte layer, 4-anode plate, 5-anode catalyst layer, 6-diaphragm / ion exchange membrane, 7-cathode catalyst layer, 8-cathode plate, 9-cathode electrolyte layer, 10-cathode mass transfer layer, 11-cathode hygroscopic medium layer, 12-energy supply module, 13-oxygen scrubber, 14-oxygen dryer, 15-oxygen collection bottle, 16-hydrogen scrubber, 17-hydrogen dryer, 18-hydrogen collection bottle.

[0046] Figure 2 This is the stability diagram of hydrogen production from air in Example 1;

[0047] Figure 3 This is the stability diagram of hydrogen production from air in Example 2;

[0048] Figure 4 This is the stability diagram of hydrogen production from air in Example 3;

[0049] Figure 5 This is the stability diagram of hydrogen production from air in Example 4. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments. However, this should not be construed as limiting the scope of the above-mentioned subject matter of the present invention to the following embodiments. Without departing from the above-mentioned technical concept of the present invention, various substitutions and modifications can be made according to common technical knowledge and customary means in the art, and all of these should be included within the scope of the present invention.

[0051] Example 1:

[0052] An air hydrogen production system, the structural diagram is as follows Figure 1As shown, the system includes an electrolysis device consisting of an anode chamber, a cathode chamber and a diaphragm arranged between the cathode and anode chambers, a power supply device, a primary phase change migration device, a secondary phase change migration device and an electrolytic catalytic hydrogen production device; the power supply device is respectively connected to the cathode plate and the anode plate for providing energy; the secondary phase change migration device and the primary phase change migration device are sequentially arranged on the periphery of the electrolysis device, and the electrolytic catalytic hydrogen production device is arranged inside the electrolysis device.

[0053] The power supply of the power supply device is an external power supply.

[0054] The secondary phase change migration device includes an anode mass transfer layer 2, an anode electrolyte layer 3, a cathode electrolyte layer 9, and a cathode mass transfer layer 10; the anode electrolyte layer 3 is laid in the anode chamber, the cathode electrolyte layer 9 is laid in the cathode chamber, the anode mass transfer layer 2 is arranged on the outer layer of the anode electrolyte layer 3, and the cathode mass transfer layer 10 is arranged on the outer layer of the cathode electrolyte layer 9.

[0055] The primary phase change migration device comprises an anode hygroscopic dielectric layer 1 and a cathode hygroscopic dielectric layer 11 . The anode hygroscopic dielectric layer 1 is connected to the anode mass transfer layer 2 , and the cathode hygroscopic dielectric layer 11 is connected to the cathode mass transfer layer 10 .

[0056] An anode plate 4 is arranged in the anode chamber, and a cathode plate 8 is arranged in the cathode chamber.

[0057] Preferably, the electrolytic catalytic hydrogen production device includes an anode catalyst layer 5 and a cathode catalyst layer 7, the anode catalyst layer 5 is connected to the anode plate 4, and the cathode catalyst layer 7 is connected to the cathode plate 8; the cathode plate and the anode plate are both stainless steel plates.

[0058] The cathode mass transfer layer and the anode mass transfer layer used in this embodiment are both PTFE membranes with a pore size of 1 μm, and the diaphragm used is a hydrophilic ceramic diaphragm.

[0059] The entire hydrogen production system is placed in the air. The anode hygroscopic medium 1 (30% lithium chloride solution by mass) and the cathode hygroscopic medium 11 (30% lithium chloride solution by mass) absorb water molecules from the air through the interfacial pressure difference, causing the water molecules to undergo primary migration. Under the action of the interfacial pressure difference between the anode hygroscopic medium 1 and the anode electrolyte layer 3 (50wt% KOH solution), and the cathode hygroscopic medium 11 and the cathode electrolyte layer 9 (50wt% KOH solution), water is transferred from the hygroscopic medium to the electrolyte, undergoing secondary migration. Water undergoes a reduction hydrogen evolution reaction on the surface of the cathode catalyst layer 7 (nickel-platinum-plated mesh), according to the following reaction formula:

[0060] 2H2O+2e - →H2+2OH -

[0061] The generated OH -The oxygen is transferred to the anode catalyst layer 5 (1 cm x 1 cm nickel-molybdenum foam) through the diaphragm 6, and an oxidation reaction occurs to produce oxygen. The reaction formula is as follows:

[0062]

[0063] The implementation effect: During the experiment, the size of the anode hygroscopic medium layer 1 and the cathode hygroscopic medium layer 11 was set to 10cmx10cmx10cm, wherein the hygroscopic medium was a 30wt% lithium chloride solution, and the cathode mass transfer layer 10 and the anode mass transfer layer 2 were both PTFE membranes with a pore size of 1um; the size of the anode electrolyte layer and the cathode electrolyte layer was set to 10cmx10cmx1.5cm, and the anode electrolyte layer 3 and the cathode electrolyte layer 9 were both 50wt% KOH solutions. Under these conditions, about 2g of water migrated from the air to the hygroscopic medium within 200min, and about 1.75g ​​of water migrated from the hygroscopic medium to the electrolyte. The system forms a stable water supply through multi-stage migration. At 1.85V and 100mA / cm 2 Under the condition of 1cm, it can be stable for at least 24h; under the condition of 1cm 2 Under the catalytic layer area, 1.09LH2 was collected, and the electrolysis efficiency was close to 100%. Figure 2 shown.

[0064] Example 2:

[0065] An air hydrogen production system, the structural diagram is as follows Figure 1 As shown, the structural setting is consistent with that of Example 1, with the only difference being:

[0066] The entire system is placed in air. The anode hygroscopic medium 1 (a 30 wt% lithium chloride and calcium chloride composite solution) and the cathode hygroscopic medium 11 (a 30 wt% lithium chloride and calcium chloride composite solution) absorb water molecules from the air through the interfacial pressure difference, causing the water molecules to undergo primary migration. Under the influence of the interfacial pressure difference between the anode hygroscopic medium 1 and the anode electrolyte layer 3 (a 40 wt% H2SO4 solution), and the cathode hygroscopic medium 11 and the cathode electrolyte layer 9 (a 40 wt% H2SO4 solution), water is transferred from the hygroscopic medium to the electrolyte, undergoing secondary migration. Water undergoes an oxidation reaction in the anode catalyst layer 5 (Ir / C) to produce oxygen, according to the following reaction formula:

[0067] 2H2O-4e - →O2+4H +

[0068] The generated H + The hydrogen is transferred to the surface of the cathode catalyst layer 7 (Pt / C) through the ion exchange membrane 6 (Nafion membrane) to undergo a reduction hydrogen evolution reaction. The reaction formula is as follows:

[0069] 2H + +2e- →H2

[0070] The implementation effect: The structure is the same as that of Example 1, with the only difference being the change in the electrolyte layer, which uses 40 wt% H2SO4 solution, the cathode catalyst layer is replaced by Pt / C, the anode catalyst layer is replaced by Ir / C, and the diaphragm / ion exchange membrane is Nafion membrane. The result: The system forms a stable water supply through multi-stage migration, at 2V, 50mA / cm 2 Under the condition of , it can be stable for at least 24h, and the electrolysis efficiency is greater than 99%. Figure 3 .

[0071] Example 3

[0072] The structural diagram of the air hydrogen production system is as follows: Figure 1 As shown, the structural setting is consistent with that of Example 1, with the only difference being:

[0073] The entire system is placed in air. The anode hygroscopic medium 1 (a 30% lithium chloride and calcium chloride composite solution) and the cathode hygroscopic medium 11 (a 30% lithium chloride and calcium chloride composite solution) absorb water molecules from the air through the interfacial pressure difference, causing the water molecules to undergo primary migration. Under the influence of the interfacial pressure difference between the anode hygroscopic medium 1 and the anode electrolyte layer 3 (PVA gel), and the cathode hygroscopic medium 11 and the cathode electrolyte layer 9 (PVA gel), water is transferred from the hygroscopic medium to the electrolyte, undergoing secondary migration. Water undergoes a reduction hydrogen evolution reaction on the surface of the cathode catalyst layer 7 (nickel-platinum-coated mesh), according to the following reaction formula:

[0074] 2H2O+2e - →H2+2OH -

[0075] The generated OH- is transferred to the anode catalyst layer 5 (nickel molybdenum foam) through the diaphragm 6 (hydrophilic ceramic diaphragm), and an oxidation reaction occurs to produce oxygen. The reaction formula is as follows:

[0076]

[0077] The implementation effect: The structure is the same as that of Example 1, the only difference is that the electrolyte layer is changed, and PVA gel is used here. The result: The system forms a stable water supply through multi-stage migration, at 2.6V, 100mA / cm 2 Under these conditions, it can be stable for at least 24 hours, and the electrolysis efficiency is greater than 99%. Figure 4 .

[0078] Example 4

[0079] The structural diagram of the air hydrogen production system is as follows: Figure 1 As shown, the structural setting is consistent with that of Example 1, with the only difference being:

[0080] The entire system is placed in air. The anode hygroscopic medium 1 (calcium chloride) and the cathode hygroscopic medium 11 (calcium chloride) absorb water molecules from the air through the interfacial pressure difference, causing the water molecules to undergo primary migration. Under the influence of the interfacial pressure difference between the anode hygroscopic medium 1 and the anode electrolyte layer 3 (PAMPS gel), and the cathode hygroscopic medium 11 and the cathode electrolyte layer 9 (PAMPS gel), water moves from the hygroscopic medium into the electrolyte, undergoing secondary migration. Water undergoes an oxidation reaction in the anode catalyst layer 5 (Ir / C) to produce oxygen, according to the following reaction formula:

[0081] 2H2O-4e - →O2+4H +

[0082] The generated H + The hydrogen is transferred to the surface of the cathode catalyst layer 7 (Pt / C) through the ion exchange membrane 6 (Nafion membrane) to undergo a reduction hydrogen evolution reaction. The reaction formula is as follows:

[0083] 2H + +2e - →H2

[0084] The implementation effect: The structure is the same as that of Example 1, with the only difference being the change in the electrolyte layer, which uses PAMPS gel, the cathode catalyst layer uses Pt / C, the anode catalyst layer uses Ir / C, and the diaphragm / ion exchange membrane uses Nafion membrane. The result: The system forms a stable water supply through multi-stage migration, at 2.8V, 30mA / cm 2 Under the condition of Figure 5 .

[0085] Example 5

[0086] In this embodiment, a direct air electrolysis hydrogen production system is provided. The hydrogen production system includes the direct air electrolysis hydrogen production device described in the above embodiment 1, and further includes:

[0087] An oxygen collection unit and a hydrogen collection unit, each of the oxygen collection unit and the hydrogen collection unit is connected to the anode catalyst layer 5 and the cathode catalyst layer 7 respectively, so as to dry, collect and process the produced oxygen and hydrogen respectively.

[0088] The oxygen collection unit includes an oxygen scrubber 13 connected to the anode catalyst layer 5. The oxygen scrubber 13 is connected to an oxygen dryer 14, which is connected to an oxygen collection bottle 15. The oxygen produced by the oxygen evolution reaction on the anode catalyst layer passes through a pipeline through the oxygen scrubber 13 and the oxygen dryer 14 for washing and drying, and is then collected in the oxygen collection bottle 15 for storage and subsequent use. The hydrogen collection unit includes a hydrogen scrubber 16 connected to the cathode catalyst layer 7. The hydrogen scrubber 16 is connected to a hydrogen dryer 17, which is connected to a hydrogen collection bottle 18. The hydrogen produced by the reduction hydrogen evolution reaction on the cathode catalyst layer 7 passes through the hydrogen scrubber 16 and the hydrogen dryer 17 for washing and drying, removing entrained hydrogen, and is then collected through a pipeline into the hydrogen collection bottle 18 for storage and subsequent use.

[0089] The entire system can be designed into an integrated system that is easy to carry or prepare on a large scale according to the demand for hydrogen production. It can be used in various environments with circulating air, including deserts, rainforests, islands, etc., and can perform continuous in-situ hydrogen production without being restricted by time and space.

[0090] The above examples are merely preferred embodiments of this patent, but the scope of protection of this patent is not limited thereto. It should be noted that, without departing from the principles of this patent, those skilled in the art may make improvements and modifications based on the technical solution and patent concept of this patent, and such improvements and modifications shall also be considered within the scope of protection of this patent.

Claims

1. A method for producing hydrogen from air, characterized in that The method includes the following steps: a power supply module provides energy input, a hygroscopic medium is placed in an atmospheric environment, and under the action of the interface pressure difference between the air and the hygroscopic medium, water molecules are induced to liquefy and absorb by the hygroscopic medium to undergo a primary phase change migration; at the same time, driven by the interface pressure difference between the hygroscopic medium and the electrolyte, the moisture in the hygroscopic medium undergoes a secondary phase change migration through the water vapor mass transfer layer and enters the electrolyte; at the same time, the hydrophobic effect of the water vapor mass transfer layer effectively blocks impurities in the solution, and during electrolysis, the water in the electrolyte is consumed to produce hydrogen and oxygen, and induces electrolyte regeneration to further maintain the interface pressure difference; when the moisture migrated in the primary phase change and the secondary phase change is equal to the amount of water consumed in hydrogen production by electrolysis, dynamically stable and balanced air hydrogen production is achieved.

2. The method for producing hydrogen from air according to claim 1, wherein The specific steps include: The power supply module is connected to the cathode plate and the anode plate to provide electrical energy for the hydrogen production reaction; The hygroscopic medium layer is in direct contact with the air. By utilizing the pressure difference between the air and the hygroscopic interface, the hygroscopic medium will induce the liquefaction of water molecules in the air to form a first-order phase change migration. At the same time, under the action of the interface pressure difference between the cathode electrolyte layer and the cathode hygroscopic medium layer, and between the anode electrolyte layer and the anode hygroscopic medium layer, the water in the hygroscopic medium layer undergoes secondary migration into the electrolyte layer. The mass transfer layer between the two prevents mutual penetration due to the hydrophobic effect and transmits water vapor molecules through its own porous structure. After water molecules enter the electrolyte layer, if the electrolyte is alkaline, a reduction hydrogen evolution reaction will first occur on the surface of the cathode catalyst layer, and the generated OH - It is transferred to the anode catalyst layer through the diaphragm / ion exchange membrane, where an oxidation reaction occurs to produce oxygen; If the electrolyte is acidic, the oxidation reaction will first occur on the surface of the anode catalyst layer, and the generated H + It is transferred to the cathode catalyst layer through the diaphragm / ion exchange membrane, where a reduction reaction occurs to produce hydrogen.

3. An air hydrogen production system, characterized in that: An electrolysis device comprising an anode chamber, a cathode chamber, and a diaphragm disposed between the anode and cathode chambers, a power supply device, a primary phase change migration device, a secondary phase change migration device, and an electrolytic catalytic hydrogen production device; the power supply device is connected to the cathode plate and the anode plate, respectively, for providing energy; A secondary phase change migration device and a primary phase change migration device are sequentially arranged on the periphery of the electrolysis device, and an electrolytic catalytic hydrogen production device is arranged inside the electrolysis device.

4. The air hydrogen production system according to claim 3, characterized in that: The secondary phase change migration device includes an anode mass transfer layer, an anode electrolyte layer, a cathode electrolyte layer, and a cathode mass transfer layer; the anode electrolyte layer is laid in the anode chamber, the cathode electrolyte layer is laid in the cathode chamber, the anode mass transfer layer is arranged on the outer layer of the anode electrolyte layer, and the cathode mass transfer layer is arranged on the outer layer of the cathode electrolyte layer.

5. The air hydrogen production system according to claim 3, characterized in that: The primary phase change migration device comprises an anode hygroscopic medium layer and a cathode hygroscopic medium layer. The anode hygroscopic medium layer is connected to the anode mass transfer layer, and the cathode hygroscopic medium layer is connected to the cathode mass transfer layer.

6. The air hydrogen production system according to claim 3, characterized in that: An anode plate is arranged in the anode chamber, and a cathode plate is arranged in the cathode chamber.

7. The air hydrogen production system according to claim 3, characterized in that: The electrolytic catalytic hydrogen production device comprises an anode catalyst layer and a cathode catalyst layer. The anode catalyst layer is connected to the anode plate, and the cathode catalyst layer is connected to the cathode plate.

8. The air hydrogen production system according to claim 7, characterized in that: The electrolytic catalytic hydrogen production device also includes an oxygen scrubber, an oxygen dryer, an oxygen collecting bottle, a hydrogen scrubber, a hydrogen dryer and a hydrogen collecting bottle; under the action of the anode catalyst layer, the oxygen generated in the anode chamber is passed into the oxygen scrubber and the oxygen dryer connected to the anode chamber in sequence, and finally collected in the oxygen collecting bottle; under the action of the cathode catalyst layer, the hydrogen generated in the cathode chamber is passed into the hydrogen scrubber and the hydrogen dryer connected to the cathode chamber in sequence, and finally collected in the hydrogen collecting bottle.

9. The air hydrogen production system according to claim 4, characterized in that: The anode mass transfer layer and the cathode mass transfer layer include a waterproof and breathable layer which is any one of TPU, PDMS, PTFE with a pore size of 0.1-100 μm, or a porous waterproof and breathable layer prepared by spraying, screen printing, or electrostatic adsorption of graphene, PVDF particles, PTFE membrane, or PTFE particles.

10. The air hydrogen production system according to claim 4, characterized in that: The hygroscopic medium in the anode hygroscopic medium layer and the cathode hygroscopic medium layer includes any one of PVA, PAMPS, and PAAM hygroscopic gel or any one of glycerol, CaSO4, MgSO4, LiBr, CaCl2, CsF, and LiCl liquid absorbents with a concentration of 30-100wt%; the electrolyte in the anode electrolytic layer and the cathode electrolytic layer includes any one of PVA, PAMPS, and PAAM solid gel electrolytes or Na2SO4, K2SO4, K3PO4, K2CO3, NaOH, and KOH liquid electrolytes with a concentration of 30-100wt%; the anode catalytic electrode includes a FexCoyNiz type catalyst, iridium tantalum, ruthenium iridium, NiFe-LDH, or NiFeCu alloy catalyst-loaded titanium mesh or Mo-Ni3S2; the hydrogen evolution catalyst includes a platinum mesh, a nickel-plated platinum mesh, or Pt / C.

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