Seawater electrolysis hydrogen production device
By using gel electrolytes and hydrophobic permeable membranes in seawater electrolysis hydrogen production devices, the problems of catalyst corrosion and hydrodynamic disturbances in seawater electrolysis hydrogen production have been solved, achieving efficient and safe hydrogen production, simplifying the system structure and reducing energy consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SICHUAN UNIV
- Filing Date
- 2025-05-16
- Publication Date
- 2026-05-12
AI Technical Summary
Existing seawater electrolysis hydrogen production technology faces safety hazards and high energy consumption issues caused by catalyst corrosion, membrane pore blockage, and hydrodynamic disturbances, which limit its application in marine environments.
A gel electrolyte is used as the electrolyte in the direct seawater electrolysis hydrogen production system. The migration of gaseous water molecules is induced by a hydrophobic and breathable membrane to achieve a highly efficient ion pathway between the anode and cathode. The multifunctionality of the gel electrolyte is used to separate hydrogen and oxygen gases, simplifying the device structure.
It achieves efficient, safe and stable production of hydrogen through seawater electrolysis, reduces energy consumption, simplifies system structure, adapts to the fluctuating marine environment, and avoids gas cross-mixing and liquid seawater infiltration.
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Figure CN224227230U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of hydrogen electrolysis technology, and more specifically, to a seawater electrolysis hydrogen production device. Background Technology
[0002] As an important pathway for clean energy conversion, the large-scale application of water electrolysis for hydrogen production is significantly constrained by the cost of raw material acquisition. Although the marine environment possesses abundant water resources, existing water electrolysis systems generally use pure water as the feed medium, primarily due to multiple technical bottlenecks in seawater electrolysis. Firstly, the rich multi-ionic composition of seawater can induce electrochemical corrosion at the active sites of the electrode catalyst, leading to a continuous decline in catalytic efficiency. Secondly, the precipitation of sparingly soluble salts formed by metal ions on the surface of the ion exchange membrane during electrolysis can clog the membrane pores, significantly reducing proton transport efficiency and thus affecting system stability. To address these issues, existing technologies typically require multi-stage reverse osmosis and ion exchange water treatment devices for seawater purification, which not only increases equipment construction costs but also generates additional pretreatment energy consumption.
[0003] Furthermore, during electrolytic hydrogen production operations in dynamic marine conditions, the mechanical vibrations of ships or floating platforms and the impact of waves can cause unsteady fluid flow inside the electrolyzer. This hydrodynamic disturbance poses two safety hazards: first, the electrolyte is prone to leakage through the sealing interface under pressure pulsation, resulting in the leakage of highly corrosive alkaline or acidic solutions; second, the disordered movement of the gas-liquid two-phase flow can intensify the cross-mixing of hydrogen and oxygen gases in the electrode area, posing a serious risk of combustion and explosion when the concentration of the mixed gas reaches the explosive limit. These technical defects severely restrict the engineering application of seawater electrolytic hydrogen production technology in marine environments. Utility Model Content
[0004] The purpose of this application is to overcome the shortcomings of existing technologies and provide a seawater electrolysis hydrogen production device. The device uses a gel electrolyte as the electrolyte in the direct seawater electrolysis hydrogen production system. It induces gaseous water molecules in seawater to migrate into the gel through a hydrophobic and breathable membrane, conducts hydroxide ions to achieve an efficient ion pathway between the anode and cathode, and effectively separates hydrogen and oxygen to avoid gas cross-contamination and achieve hydrogen production.
[0005] The objective of this application is achieved through the following technical solution:
[0006] In a first aspect, this application proposes a seawater electrolysis hydrogen production device, the device comprising, from left to right, a left outer shell, a first hydrophobic and breathable porous membrane, a cathode conductive sheet, a cathode catalyst, a gel electrolyte, an anode catalyst, an anode conductive sheet, a second hydrophobic and breathable porous membrane, and a right outer shell;
[0007] The first hydrophobic and breathable porous membrane is disposed on the inner side of the upper half of the left outer shell and is tightly fitted with the through hole. The second hydrophobic and breathable porous membrane is disposed on the inner side of the upper half of the right outer shell. Both the first and second hydrophobic and breathable porous membranes are tightly fitted with the through hole.
[0008] The upper half of the cathode conductive sheet is provided with pores of the same shape as the first hydrophobic and breathable porous membrane, the upper half of the anode conductive sheet is provided with pores of the same shape as the second hydrophobic and breathable porous membrane, and the lower half of both the cathode conductive sheet and the anode conductive sheet are provided with reaction channels.
[0009] The cathode catalyst is in contact with the lower side of the gel electrolyte, and the anode catalyst is in contact with the lower side of the gel electrolyte.
[0010] Both the upper parts of the left and right outer shells are provided with through holes to allow seawater to enter and come into contact with the hydrophobic and breathable porous membrane.
[0011] The first and second hydrophobic and breathable porous membranes are fixed inside the shell and separate the seawater from the gel electrolyte, allowing gaseous water molecules to pass through while blocking liquid seawater.
[0012] Gel electrolytes are used to drive the migration of gaseous water molecules in seawater into the interior of the gel electrolyte via a saturated vapor pressure difference.
[0013] The cathode conductive sheet and cathode catalyst are used to electrolyze water molecules to generate hydrogen and hydroxide ions;
[0014] Anode catalyst and anode conductive sheet are used to electrolyze hydroxide ions to generate oxygen;
[0015] A hydrogen outlet is located at the lower part of the left outer casing, which is connected to the cathode area for discharging and collecting hydrogen.
[0016] An oxygen outlet is located at the bottom of the right-side casing, which is connected to the anode area for discharging and collecting oxygen.
[0017] In one possible implementation, both the first hydrophobic and breathable porous membrane and the second hydrophobic and breathable porous membrane are porous membranes made of polytetrafluoroethylene.
[0018] In one possible implementation, the symmetrically arranged left and right outer shells are made of corrosion-resistant plastic.
[0019] In one possible implementation, the through holes are arranged in an array.
[0020] In one possible implementation, anti-backflow valves are installed at the outlets of the hydrogen and oxygen outlets.
[0021] In one possible implementation, the gel electrolyte is composed of at least one polymer selected from polyvinyl alcohol, polyacrylic acid, or polyacrylamide.
[0022] In one possible implementation, the gel electrolyte has a three-dimensional interconnected channel formed by cryogenic salting out, and the channel is permeated with a 20-50 wt% potassium hydroxide solution.
[0023] In one possible implementation, the cathode conductive sheet and the anode conductive sheet are conductive sheets made of stainless steel, copper, titanium, or nickel.
[0024] In one possible implementation, the cathode catalyst and the anode catalyst are catalysts made of platinum or nickel-based composite materials.
[0025] The main solution and its various further alternatives described above can be freely combined to form multiple solutions, all of which are solutions that can be adopted and are claimed in this application; furthermore, the (non-conflicting alternatives) can also be freely combined with each other and with other alternatives. Those skilled in the art, after understanding the solution of this application, will realize from the prior art and common general knowledge that there are many combinations, all of which are technical solutions to be protected by this application, and will not be exhaustively listed here.
[0026] This application discloses a seawater electrolysis hydrogen production device. A hydrophobic and breathable porous membrane is tightly fitted with through-holes, blocking liquid seawater while allowing gaseous water molecules to pass through. The upper half of the cathode and anode conductive sheets has pores corresponding to the hydrophobic membrane, and the lower half has reaction channels. The gel electrolyte has three-dimensional interconnected channels and is permeated with a high-concentration electrolyte solution. Gaseous water molecules in the seawater migrate into the gel electrolyte inside the device through vapor pressure difference. The cathode catalyst contacts one side of the lower part of the gel electrolyte, catalyzing water decomposition to generate hydrogen gas; the anode catalyst contacts the other side of the lower part of the gel electrolyte, catalyzing the generation of oxygen from hydroxide ions. The gas barrier function of the gel electrolysis hydrogen production allows for the independent separation and collection of hydrogen and oxygen gases at the hydrogen and oxygen outlets. By using the hydrophobic and breathable porous membrane to block liquid seawater, the gel electrolyte to self-humidify, conduct ions, and provide gas barrier functions, the structure of the seawater electrolysis hydrogen production system is simplified, enabling direct and efficient hydrogen production without seawater desalination. Attached Figure Description
[0027] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0028] Figure 1 A schematic diagram of a seawater electrolysis hydrogen production device according to an embodiment of this application is shown.
[0029] Figure 2 A schematic flowchart of a gel electrolyte preparation method proposed in an embodiment of this application is shown.
[0030] Figure 3 A schematic diagram showing the water migration rate of gel electrolytes prepared with KOH solutions of different concentrations and the corresponding current densities that can be satisfied is presented.
[0031] Figure 4 A schematic diagram showing the changes in ionic conductivity of gel electrolytes prepared with KOH solutions of different concentrations is presented.
[0032] Figure 5 The stress-strain curves of gel electrolytes prepared with KOH solutions of different concentrations are shown.
[0033] Reference numerals: 1-Left outer shell; 2-First hydrophobic and breathable porous membrane; 3-Cathode conductive sheet; 4-Cathode catalyst; 5-Gel electrolyte; 6-Anode catalyst; 7-Anode conductive sheet; 8-Second hydrophobic and breathable porous membrane; 9-Right outer shell; 10-Through hole; 11-Hydrogen outlet; 12-Oxygen outlet. Detailed Implementation
[0034] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.
[0035] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0036] In existing technologies, the presence of numerous impurity ions in seawater negatively impacts the electrolysis system, causing catalyst corrosion and ion precipitation that clogs membrane pores, making stable operation difficult. Therefore, current mature water electrolysis hydrogen production methods all use pure water as raw material. Using seawater for electrolysis requires water purification equipment and additional energy consumption for purification. Furthermore, in the fluctuating marine environment, the liquid electrolyte within the electrolysis system can experience safety issues such as corrosive electrolyte leakage and gas cross-contamination due to liquid flow and pressure fluctuations.
[0037] Therefore, in order to solve the above-mentioned technical problems, this application proposes a seawater electrolysis hydrogen production device. A gel with water molecule capture, high ionic conductivity and mechanical strength is used as the electrolyte in the direct seawater electrolysis hydrogen production system. The gel induces gaseous water molecules in seawater to migrate into the gel through a hydrophobic and breathable membrane, conducts hydroxide ions to realize an efficient ion pathway between the anode and cathode, effectively separates hydrogen and oxygen to avoid gas cross-contamination and achieve safe hydrogen production. The multifunctionality of the gel electrolyte further simplifies the structure of the seawater electrolysis hydrogen production device, which will be described in detail below.
[0038] Please refer to Figure 1 , Figure 1 The diagram shows a structural schematic of a seawater electrolysis hydrogen production device according to an embodiment of this application. The device includes a left outer shell 1, a first hydrophobic and breathable porous membrane 2, a cathode conductive sheet 3, a cathode catalyst 4, a gel electrolyte 5, an anode catalyst 6, an anode conductive sheet 7, a second hydrophobic and breathable porous membrane 8, and a right outer shell 9 arranged from left to right.
[0039] The first hydrophobic and breathable porous membrane 2 is disposed on the inner side of the upper half of the left outer shell 1 and is tightly fitted with the through hole. The second hydrophobic and breathable porous membrane 5 is disposed on the inner side of the upper half of the right outer shell 9. Both the first hydrophobic and breathable porous membrane 2 and the second hydrophobic and breathable porous membrane 8 are tightly fitted with the through hole.
[0040] The upper half of the cathode conductive sheet 3 is provided with pores of the same shape as the first hydrophobic and breathable porous membrane 2, the upper half of the anode conductive sheet 6 is provided with pores of the same shape as the second hydrophobic and breathable porous membrane 8, and the lower half of both the cathode conductive sheet 3 and the anode conductive sheet 7 are provided with reaction channels.
[0041] The cathode catalyst 4 is in contact with the lower part of the gel electrolyte 5, and the anode catalyst 6 is in contact with the upper part of the gel electrolyte 5.
[0042] Both the left outer shell 1 and the right outer shell 9 have through holes 10 at the top to allow seawater to enter and come into contact with the hydrophobic and breathable porous membrane.
[0043] The first hydrophobic and breathable porous membrane 2 and the second hydrophobic and breathable porous membrane 8 are fixed inside the shell and separate the seawater from the gel electrolyte 5, allowing gaseous water molecules to pass through while blocking liquid seawater.
[0044] Gel electrolyte 5 is used to drive the migration of gaseous water molecules in seawater to the interior of gel electrolyte 5 through saturated vapor pressure difference;
[0045] The cathode conductive sheet 3 and the cathode catalyst 4 are used to electrolyze water molecules to generate hydrogen and hydroxide ions.
[0046] Anode catalyst 6 and anode conductive sheet 7 are used to electrolyze hydroxide ions to generate oxygen.
[0047] A hydrogen outlet 11 is provided at the lower part of the left outer casing 1, which is connected to the cathode area and is used to discharge and collect hydrogen.
[0048] An oxygen outlet 12 is provided at the lower part of the right outer casing 9, which is connected to the anode area and is used to discharge and collect oxygen.
[0049] The working principle of the seawater electrolysis hydrogen production device is as follows: Seawater enters through the through-holes 10 at the top of the left outer shell 1 and the right outer shell 9, and comes into contact with the first hydrophobic and breathable porous membrane 2 and the second hydrophobic and breathable porous membrane 8. Due to the vapor pressure difference between the gel electrolyte 5 and the seawater, gaseous water molecules in the seawater spontaneously migrate into the interior of the gel electrolyte 5 through the hydrophobic and breathable porous membrane under the impetus of the vapor pressure difference, while liquid seawater is blocked outside the membrane.
[0050] An external power source transfers electrons to the cathode catalyst 4 through the cathode conductive plate 3. Water molecules gain electrons on the cathode catalyst 4 and decompose into hydrogen gas and hydroxide ions. The reaction is: 2H2O + 2e- on the cathode side. - →H2+2OH - The generated hydrogen gas is discharged through hydrogen outlet 11 and collected and stored. Hydroxide ions migrate from gel electrolyte 5 to anode catalyst 6 under the influence of an electric field. Upon reaching anode catalyst 6, they lose electrons to produce oxygen. The reaction is as follows: Anode side... The generated oxygen is discharged through oxygen outlet 12 and collected and stored.
[0051] The electrolysis process consumes water molecules in the gel electrolyte, which maintains the saturated vapor pressure difference between the gel electrolyte and seawater. This allows the electrolytic hydrogen production process and the water molecule migration and capture process of the gel electrolyte to reach a dynamic balance, enabling the continuous acquisition of water molecules from seawater and achieving stable hydrogen production.
[0052] Water molecules in the upper part of the gel electrolyte are transferred to the lower part of the gel electrolyte under the influence of the concentration gradient.
[0053] Within the gel electrolyte, due to the concentration gradient, water molecules move from the top to the bottom. This movement is a natural diffusion process of water molecules from areas of high concentration to areas of low concentration, which helps maintain the balance of water molecule distribution throughout the electrolyte, thereby supporting the continuous progress of the electrolysis reaction.
[0054] Both the first and second hydrophobic and breathable porous membranes are porous membranes made of polytetrafluoroethylene.
[0055] These two hydrophobic and breathable porous membranes are made of polytetrafluoroethylene (PTFE), which has excellent chemical stability and hydrophobicity. The porous structure of PTFE allows gaseous water molecules to pass through, but effectively blocks the permeation of liquid seawater, thus forming a selective isolation layer between the seawater and the electrolysis zone inside the device. This ensures that only water vapor enters the electrolysis reaction area, preventing salt and other impurities from interfering with the hydrogen production process.
[0056] The symmetrically arranged left and right outer shells are made of corrosion-resistant plastic.
[0057] The left and right outer shells of the device are made of corrosion-resistant plastic with a symmetrical design, which can resist corrosive substances in the seawater environment while ensuring the mechanical strength and sealing of the structure. The symmetrical layout simplifies the assembly process and ensures uniform pressure distribution inside the device, making it suitable for stable operation in the undulating marine environment.
[0058] The through holes are arranged in an array.
[0059] The perforations on the top of the outer shell are evenly arranged in an array. This design increases the contact area between seawater and the hydrophobic and breathable membrane, improving the migration efficiency of gaseous water molecules. The array distribution also avoids local blockage, ensuring that water molecules continuously and evenly pass through the porous membrane into the device, maintaining the continuity of the electrolysis reaction.
[0060] Backflow prevention valves are installed at the outlets of hydrogen and oxygen.
[0061] Installing anti-backflow valves at the hydrogen and oxygen outlets can prevent the gas from flowing back into the reaction zone when the external pressure changes or the equipment is shut down, thus avoiding the safety hazards caused by the mixing of hydrogen and oxygen.
[0062] The gel electrolyte is composed of at least one polymer selected from polyvinyl alcohol, polyacrylic acid, or polyacrylamide.
[0063] The gel electrolyte uses polymers containing hydrophilic groups, such as polyvinyl alcohol, polyacrylic acid, or polyacrylamide, as the matrix material. These polymers form a three-dimensional network structure through hydrogen bonds or cross-linking between molecular chains, which can both adsorb water and have good mechanical toughness, adapting to the physical deformation in the marine environment.
[0064] The gel electrolyte has three-dimensional interconnected channels formed by freeze salting out, and 20-50 wt% potassium hydroxide solution permeates into the channels.
[0065] By freezing the polymer solution and immersing it in a high-concentration electrolyte solution, three-dimensional interconnected channels, left over from the melting of ice crystals, are formed inside the gel. These channels not only provide pathways for water molecule migration but also enhance ionic conductivity through the infiltration of 20-50 wt% potassium hydroxide solution, while maintaining the vapor pressure difference between the gel and seawater, driving the spontaneous migration of water molecules.
[0066] The cathode and anode conductive sheets are made of stainless steel, copper, titanium, or nickel.
[0067] The cathode and anode conductive plates are made of stainless steel, copper, titanium, or nickel metal. Their high specific surface area and porous structure enhance electron transport efficiency and provide a stable supporting substrate for the catalyst. The porous design also allows for the rapid diffusion of electrolysis products (such as hydroxide ions), reducing reaction resistance and improving electrolysis efficiency.
[0068] The cathode catalyst and the anode catalyst are platinum or nickel-based composite materials.
[0069] The cathode and anode use platinum or nickel-based composite materials as catalysts, respectively. Platinum catalysts have extremely high hydrogen evolution reaction activity, while nickel-based materials are less expensive and have strong corrosion resistance.
[0070] It is worth noting that the gel electrolyte in this application is alkaline, conducting the anode and cathode by transferring hydroxide ions, but it can also be replaced with an acidic gel capable of transferring protons. The waterproof and breathable membrane used separates seawater from the gel electrolyte, preventing direct contact between liquid seawater and gaseous water molecules, while allowing gaseous water molecules to pass through. This membrane can also be replaced with hydrophobic carbon paper or similar materials. The device's shape and functional area layout are flexible and can be adjusted to different shapes as needed, such as circular. Furthermore, the positions of water molecule migration and hydrogen electrolysis can be interchanged, such as water molecules migrating in the lower part and hydrogen electrolysis occurring in the upper part.
[0071] Primarily designed for hydrogen production via seawater electrolysis, it is also applicable to non-pure water containing impurity ions, such as sewage and salt lake water. While mainly used as a direct electrolyte in liquid environments, it can also be used for water molecule capture and hydrogen electrolysis in humid atmospheres after the hydrophobic and breathable membrane is removed, demonstrating broad application potential and flexibility.
[0072] Based on the above-described gel electrolyte, to generate this gel electrolyte, please refer to... Figure 2 , Figure 2 This paper illustrates a flowchart of a method for preparing a gel electrolyte according to an embodiment of this application. The method includes:
[0073] Step S1: Dissolve the polymer with hydrophilic groups in deionized water, stir and heat to form a polymer matrix solution.
[0074] The polymer has a mass fraction of 3-20 wt%.
[0075] First, a polymer matrix solution is prepared by dissolving polyvinyl alcohol (or other polymers with hydrophilic groups such as polyacrylic acid or polyacrylamide) particles in deionized water, followed by vigorous stirring and heating. The heating conditions are 80-95℃ for 24 hours, with sufficiently vigorous stirring to ensure complete dissolution of the polymer particles. The polymer mass fraction in the resulting polymer matrix solution should be controlled between 3-20 wt%. Through stirring and heating, the polymer particles are fully dissolved in the deionized water, forming a homogeneous and transparent solution, providing the basic polymer matrix for the preparation of the gel electrolyte.
[0076] The polymer is at least one of polyvinyl alcohol, polyacrylic acid, and polyacrylamide. These polymers have hydrophilic groups, can dissolve in water to form a solution, and can be processed to form a gel electrolyte with a three-dimensional network structure.
[0077] Heating at 80-95℃ for 24 hours ensures that the polymer is fully dissolved.
[0078] Step S2: Inject the polymer matrix solution into a mold and freeze-mold to obtain a polymer precursor with a three-dimensional network structure.
[0079] A polymer matrix solution is injected into a mold and frozen at -20°C for 24 hours. During freezing, the water in the polymer solution freezes to form ice crystals. The formation of ice crystals exerts a compressive effect on the polymer molecular chains, causing them to approach and bond together. Simultaneously, the ice crystals occupy space, thus forming a usable three-dimensional porous structure within the polymer. After freezing, a polymer precursor with a three-dimensional network structure is obtained.
[0080] Step S3: Immerse the polymer precursor in a self-humidifying solution with high ionic conductivity. The polymer molecular chains are induced to aggregate through salting out, causing the ice crystals to melt and form interconnected channels. At the same time, electrolyte ions permeate into the polymer network structure to form a gel electrolyte.
[0081] Soaking time is 48 hours.
[0082] The polymer precursor is immersed in a high-ionic-conductivity self-humidifying solution for 48 hours. This solution can be a 20wt%-50wt% potassium hydroxide solution, or other high-ionic-conductivity self-humidifying solutions such as sodium hydroxide, sulfuric acid, phosphoric acid, or potassium phosphate. During immersion, ice crystals melt into water and precipitate from the polymer matrix. Simultaneously, water molecules between the gel molecular chains gradually precipitate, promoting further aggregation and strengthening of the polymer molecular chains. As immersion continues, electrolyte ions from the high-ionic-conductivity self-humidifying solution gradually penetrate into the polymer network structure, with some ions binding to the polymer molecular chains. Ultimately, salting out induces polymer molecular chain aggregation, causing the ice crystals to melt and form interconnected channels. Simultaneously, electrolyte ions are uniformly distributed within the polymer network, thus forming a gel electrolyte with self-humidifying properties, high ionic conductivity, and strong mechanical properties.
[0083] Based on gel electrolytes, Figure 3 The diagram shows the water migration rate of gel electrolytes prepared with KOH solutions of different concentrations and the corresponding current densities that can be met. As the KOH concentration increases, both the water migration rate and the current density that can be met by the gel electrolyte show an upward trend, indicating that a higher KOH concentration helps to improve the water absorption capacity and conductivity of the gel electrolyte, thereby supporting a higher current density.
[0084] Figure 4 A schematic diagram illustrating the changes in ionic conductivity of gel electrolytes prepared with KOH solutions of different concentrations is shown. As the KOH concentration increases, the ionic conductivity of the gel electrolyte also increases. This increase in ionic conductivity indicates enhanced ion transport capacity within the electrolyte, which is beneficial for improving ion migration efficiency during electrolysis, reducing energy loss, and ultimately improving the performance of the entire electrolytic hydrogen production system.
[0085] Figure 5 The stress-strain curves of gel electrolytes prepared with KOH solutions of different concentrations are shown. As the KOH concentration increases, both the stress and strain of the gel electrolyte increase, indicating that a higher KOH concentration can enhance the mechanical properties of the gel electrolyte, enabling it to better withstand various mechanical stresses, such as tension and compression, in practical applications, thereby improving the stability and reliability of the gel electrolyte under fluctuating environments.
[0086] The mass fraction of the high ionic conductivity self-humidifying solution is 20-50 wt%, and the appropriate concentration range helps to form an ideal gel electrolyte structure and performance.
[0087] The self-humidifying solution is at least one of potassium hydroxide, sodium hydroxide, sulfuric acid, phosphoric acid, or potassium phosphate aqueous solution. Such solutions have high ionic conductivity, which can provide good conductivity for gel electrolytes, and have self-humidifying ability, which helps to maintain the humidity of the electrolyte.
[0088] This application also proposes a gel electrolyte, which is prepared according to the above-described gel electrolyte preparation method. This gel electrolyte simultaneously achieves self-humidifying properties that induce water molecule migration, high ionic conductivity for efficient conduction of hydroxide ions, and robust mechanical properties adapted to fluctuating environments. The seawater electrolysis hydrogen production device can directly use seawater without desalination for stable hydrogen production in fluctuating environments. The gel electrolyte in the device combines the functions of water molecule capture, ion conduction, and hydrogen and oxygen gas separation, further simplifying the system structure for direct seawater electrolysis hydrogen production and making seawater hydrogen production in fluctuating marine environments more flexible, safe, and stable.
[0089] Compared with the prior art, the embodiments of this application have the following beneficial effects:
[0090] First, the device is ingeniously designed, applying gel electrolytes to the direct electrolysis of seawater to produce hydrogen, providing a new direction for the development of electrolysis hydrogen production technology.
[0091] Secondly, it eliminates the need for seawater desalination pretreatment, saving desalination energy consumption and reducing energy consumption compared to traditional seawater hydrogen production. The electrolysis process is self-humidifying, reducing the energy consumption for additional water replenishment and lowering overall system energy consumption. It directly uses non-pure water sources such as seawater, avoiding the generation of large amounts of high-salinity wastewater from seawater desalination and reducing pressure on marine ecosystems. The produced hydrogen has high purity, eliminating the need for complex gas purification, reducing the use of chemical reagents, and lowering the risk of environmental pollution.
[0092] Third, gel electrolytes have high ionic conductivity, which improves electrolysis efficiency and enables rapid hydrogen production. Their robust mechanical properties ensure stable operation in complex environments and reduce malfunctions.
[0093] Fourth, the gel electrolyte is strong and resilient, able to withstand compression, tension, and torsional stress, ensuring structural integrity and adapting to complex marine environments. The device design prevents gas cross-contamination, avoids the explosion of hydrogen-oxygen mixtures, and effectively blocks liquid seawater, preventing contamination by impurity ions and ensuring a pure and stable electrolysis process.
[0094] In summary, this application uses a gel that combines water molecule capture, high ionic conductivity, and mechanical strength as the electrolyte for a direct seawater electrolysis hydrogen production system. This gel electrolyte induces gaseous water molecules in seawater to migrate into the gel through a hydrophobic and breathable membrane, conducting hydroxide ions to achieve an efficient ion pathway between the anode and cathode. It effectively separates hydrogen and oxygen to prevent gas cross-contamination and achieve safe hydrogen production. The multifunctionality of the gel electrolyte further simplifies the seawater electrolysis hydrogen production device, making it more miniaturized and flexible. At the same time, it can adapt to fluctuating environments to achieve stable and safe direct seawater electrolysis hydrogen production, laying the foundation for future direct seawater electrolysis hydrogen production without time and space limitations. Through the hydrophobic and breathable porous membrane blocking liquid seawater, the gel electrolyte's self-humidification, ion conduction, and gas barrier functions, the structure of the seawater electrolysis hydrogen production system is simplified, enabling direct and efficient hydrogen production without seawater desalination.
[0095] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A seawater electrolysis hydrogen production device, characterized in that, The device includes, from left to right, a left outer shell, a first hydrophobic and breathable porous membrane, a cathode conductive sheet, a cathode catalyst, a gel electrolyte, an anode catalyst, an anode conductive sheet, a second hydrophobic and breathable porous membrane, and a right outer shell; The first hydrophobic and breathable porous membrane is disposed on the inner side of the upper half of the left outer shell and is tightly fitted with the through hole. The second hydrophobic and breathable porous membrane is disposed on the inner side of the upper half of the right outer shell. Both the first and second hydrophobic and breathable porous membranes are tightly fitted with the through hole. The upper half of the cathode conductive sheet is provided with pores of the same shape as the first hydrophobic and breathable porous membrane, the upper half of the anode conductive sheet is provided with pores of the same shape as the second hydrophobic and breathable porous membrane, and the lower half of both the cathode conductive sheet and the anode conductive sheet are provided with reaction channels. The cathode catalyst is in contact with the lower side of the gel electrolyte, and the anode catalyst is in contact with the lower side of the gel electrolyte. Both the upper parts of the left and right outer shells are provided with through holes to allow seawater to enter and come into contact with the hydrophobic and breathable porous membrane. The first and second hydrophobic and breathable porous membranes are fixed inside the shell and separate the seawater from the gel electrolyte, allowing gaseous water molecules to pass through while blocking liquid seawater. Gel electrolytes are used to drive the migration of gaseous water molecules in seawater into the interior of the gel electrolyte via a saturated vapor pressure difference. The cathode conductive sheet and cathode catalyst are used to electrolyze water molecules to generate hydrogen and hydroxide ions; Anode catalyst and anode conductive sheet are used to electrolyze hydroxide ions to generate oxygen; A hydrogen outlet is located at the lower part of the left outer casing, which is connected to the cathode area for discharging and collecting hydrogen. An oxygen outlet is located at the bottom of the right-side casing, which is connected to the anode area for discharging and collecting oxygen.
2. The seawater electrolysis hydrogen production apparatus as described in claim 1, characterized in that, Both the first and second hydrophobic and breathable porous membranes are porous membranes made of polytetrafluoroethylene.
3. The seawater electrolysis hydrogen production apparatus as described in claim 1, characterized in that, The symmetrically arranged left and right outer shells are made of corrosion-resistant plastic.
4. The seawater electrolysis hydrogen production apparatus as described in claim 1, characterized in that, The through holes are arranged in an array.
5. The seawater electrolysis hydrogen production apparatus as described in claim 1, characterized in that, Backflow prevention valves are installed at the outlets of hydrogen and oxygen.
6. The seawater electrolysis hydrogen production apparatus as described in claim 1, characterized in that, The gel electrolyte is composed of at least one polymer selected from polyvinyl alcohol, polyacrylic acid, or polyacrylamide.
7. The seawater electrolysis hydrogen production apparatus as described in claim 1, characterized in that, The gel electrolyte has three-dimensional interconnected channels formed by freeze salting out, and 20-50 wt% potassium hydroxide solution permeates into the channels.
8. The seawater electrolysis hydrogen production apparatus as described in claim 1, characterized in that, The cathode and anode conductive sheets are made of stainless steel, copper, titanium, or nickel.
9. The seawater electrolysis hydrogen production apparatus as described in claim 1, characterized in that, The cathode catalyst and anode catalyst are catalysts made of platinum or nickel-based composite materials.