A biomimetic photocatalytic hydrogen production device and method for simultaneous seawater desalination

Abstract

This invention provides a biomimetic photocatalytic hydrogen production and simultaneous seawater desalination device and method. The device consists of several parts, including a concentrating glass, a communicating vessel, a water absorber, and a pipe shell. First-stage, second-stage, and third-stage blades surround the pipe shell to form a biomimetic tower-like structure. Sunlight enters the concentrating glass from above and converges on each stage of the blades, directly heating the seawater in the hydrophilic material installed within each stage of the blades, causing the seawater to evaporate. Simultaneously, the hydrophilic material provides water for the photocatalyst and absorbs sunlight to catalyze the water reaction, generating a hydrogen-oxygen mixture. The water vapor is compressed downwards by the small-molecule non-condensable hydrogen gas and diffuses to the condensation chamber, where it exchanges heat with the seawater to accelerate condensation. The generated hydrogen-oxygen mixture undergoes countercurrent heat exchange with the seawater in the seawater pipe through the hydrogen-oxygen gas pipe, achieving multi-stage heat utilization. Multiple membranes can separate the products, enabling the device to produce fresh water, high-purity hydrogen, and oxygen-enriched gas.

Description

Technical Field

[0001] This invention belongs to the field of solar thermal utilization technology, specifically relating to a biomimetic photocatalytic hydrogen production from water and simultaneous seawater desalination device and method. Background Technology

[0002] With rapid economic and industrial development, society's consumption of fossil fuels has increased significantly, leading to problems such as global warming and increased environmental pollution. Developing clean energy sources is therefore urgently needed to address these issues. Hydrogen, with its high energy density, ease of storage and transportation, zero carbon emissions, and renewable nature, has become a leading representative of clean energy. Consequently, the demand for hydrogen is growing, making research into hydrogen production devices and methods extremely important.

[0003] Using solar energy to photocatalytically split water to produce hydrogen is one of the methods to achieve pollution-free hydrogen production. Its main characteristics are that it converts solar energy into hydrogen energy, and is characterized by being clean, having mild reaction conditions, and being scalable.

[0004] The basic principle of photocatalytic water splitting to produce hydrogen is that a semiconductor photocatalyst generates photogenerated electron-hole pairs under the excitation of sunlight. Electrons that migrate to the surface of the photocatalyst reduce water to hydrogen, while holes oxidize water to oxygen.

[0005] However, due to the strict requirements of the band gap of semiconductor materials for photocatalytic water splitting to produce hydrogen, most current photocatalysts can only utilize ultraviolet light and part of the visible light band in solar energy, while the infrared light band is difficult to utilize directly and is instead converted into heat dissipation. This results in low conversion efficiency of photocatalysts and a decline in overall actual performance.

[0006] On the other hand, seawater constitutes the majority of global water resources, while freshwater resources face a severe shortage. Interfacial photothermal evaporation is a typical seawater desalination technology that utilizes the heat dissipated by the infrared light band of solar energy to evaporate seawater and produce water vapor, which is eventually condensed to produce freshwater. However, the energy in the short-wavelength band of sunlight cannot be utilized, resulting in low energy efficiency.

[0007] Therefore, research combining seawater desalination with seawater photocatalytic hydrogen production technology is very important and valuable. However, seawater has a complex composition, and seawater photocatalytic hydrogen production faces many problems and difficulties. Two major issues are that the presence of various ions in seawater can affect the stable operation of photocatalysts, and seawater can corrode the surface structure of photocatalysts. Therefore, water vapor generated from seawater desalination can be provided to the photocatalyst as a reaction feedstock, because water vapor contains fewer ions, which has a less significant impact on the efficiency of the photocatalyst, and the corrosive effect of water vapor on the surface structure of the photocatalyst is much lower than that of seawater.

[0008] In summary, combining seawater technology with photocatalytic water reaction for hydrogen production can improve the efficiency and lifespan of photocatalytic water hydrogen production, while simultaneously producing two very important resources: hydrogen and freshwater. Therefore, seawater desalination and simultaneous hydrogen production devices have high research value.

[0009] However, existing seawater desalination and simultaneous hydrogen production devices have a relatively simple structure and poor integration. They require manual operation or other equipment to provide seawater or brackish water sources. At the same time, product collection is also inconvenient. Multiple parts are not integrated, resulting in a high space occupancy rate. They cannot be modularized and mass-produced, leading to low economic efficiency and limited output.

[0010] The relatively simple structure also results in low utilization efficiency of solar energy (light and heat) in existing seawater desalination and simultaneous hydrogen production devices. The heat carried by the gas generated by photocatalysis and the latent heat of condensation of water vapor are also not efficiently utilized. Furthermore, in existing devices, the coupling between seawater desalination and photocatalytic water reaction is weak; the two are independent and cannot mutually improve each other's efficiency. Summary of the Invention

[0011] In view of this, the present invention proposes a biomimetic photocatalytic hydrogen production device and method for simultaneous seawater desalination. The device can float on the sea surface or be placed in a groove filled with seawater, and directly produce fresh water, hydrogen and oxygen-enriched gas using solar energy. It is suitable for unitized and small-scale production.

[0012] The technical solution adopted by this invention to solve the technical problem is:

[0013] A biomimetic photocatalytic hydrogen production and simultaneous seawater desalination device includes a focusing glass, a base, a water inlet pipe, a water absorber, a pipe shell, a freshwater pipe, a hydrogen-oxygen gas pipe, a seawater pipe, first-stage blades, a photocatalyst, a hydrophilic material, a water-separating plate, a condensation chamber, second-stage blades, third-stage blades, a hydrophobic membrane, a membrane separation device, an oxygen-repellent membrane, a valve, an oxygen-enriched gas pipe, and a float. The device is characterized in that first-stage blades, second-stage blades, and third-stage blades are installed from top to bottom on the outer wall of the pipe shell, and the first-stage blades, second-stage blades, and third-stage blades tilt upwards from the installation point on the pipe shell towards the base, forming a tower-like biomimetic structure.

[0014] Photocatalysts are installed on the inner top edges of the first-stage blade, the second-stage blade, and the third-stage blade, and the hydrophilic material is adhered below the photocatalysts;

[0015] A condensation chamber is installed on the inner bottom of the first-stage blade, the second-stage blade, and the third-stage blade, and a water-proof plate is installed between the condensation chamber and the hydrophilic material.

[0016] The water-blocking plate can prevent seawater from flowing downwards in the hydrophilic material, but allows water vapor to pass through;

[0017] The hydrophilic material draws seawater in through a seawater pipe. The seawater in the hydrophilic material absorbs heat and heats up by using sunlight focused by a concentrating glass. Hot seawater and cold seawater are formed in the upper and lower halves of the hydrophilic material, respectively. At the same time, the hot seawater evaporates to generate water vapor.

[0018] The condensation chamber is located directly below the seawater pipe.

[0019] The upper part of the hydrophilic material allows hot seawater to seep out and come into contact with the photocatalyst above the hydrophilic material. The seeping hot seawater is catalyzed by the photocatalyst to generate a hydrogen-oxygen mixture gas. The hydrogen-oxygen mixture gas contains hydrogen and oxygen. Since the total molar mass of hydrogen is less than that of water vapor, it can act as a small molecule gas to promote the downward diffusion of the high-temperature water vapor generated in the hydrophilic material and enter the condensation chamber through the water baffle. The high-temperature water vapor entering the condensation chamber exchanges heat with the low-temperature seawater in the seawater pipe through the chamber wall to accelerate the condensation of water vapor into fresh water. Its latent heat of condensation is used to increase the temperature of the seawater in the seawater pipe.

[0020] The oxygen generated by the photocatalytic reaction, with a total molar mass greater than that of water vapor, enters the hydrophilic material downwards. In the hydrophilic material, the higher-temperature oxygen mixes thoroughly with the cold seawater and exchanges heat, raising the temperature of the cold seawater and accelerating the conversion of the cold seawater into hot seawater, thus improving desalination efficiency. The hydrogen-oxygen mixture diffuses downwards into the condensation chamber, carrying away heat from the photocatalyst. Subsequently, the hydrogen and oxygen generated by the photocatalyst from the hot seawater replenish the gas gaps left by the hydrogen-oxygen mixture, forming a gas flow cycle. This ensures the stability of the temperature of the hydrophilic material and the photocatalyst, as well as the stability of the photocatalytic reaction environment temperature and the stability of the gas pressure around the photocatalyst, preventing the seawater desalination efficiency and the photocatalytic reaction efficiency from decreasing due to changes in ambient temperature and pressure.

[0021] After the first product generation is completed, the condensation chamber and the photocatalyst form a cycle, simultaneously generating a hydrogen-oxygen mixture and water vapor.

[0022] The outer shell of the pipeline contains fresh water pipelines, hydrogen-oxygen gas pipelines, and seawater pipelines.

[0023] The hydrogen-oxygen gas pipeline is installed in close contact with the seawater pipeline on the inner side of the pipeline shell. The hydrogen-oxygen mixed gas flowing downward in the hydrogen-oxygen gas pipeline exchanges heat with the seawater flowing upward in the seawater pipeline through the pipe wall in a countercurrent manner, thereby increasing the base temperature of the seawater in the seawater pipeline.

[0024] The lower inner side of the condensation chamber in the first-stage blade, the second-stage blade, and the third-stage blade is directly connected to the fresh water pipe, the hydrogen-oxygen gas pipe, the hydrophobic film, and the oxygen-phobic film.

[0025] The first-stage blade, the second-stage blade, and the third-stage blade have a V-shaped structure, and the blades of each stage are installed in an alternating manner so that sunlight can reach the upper surface of the blades. In addition, the lower blades, which are blocked by the upper blades in the vertical direction, can also obtain the obliquely incident sunlight from the radial direction, thereby improving the utilization rate of sunlight.

[0026] The device for photocatalytic hydrogen production and simultaneous seawater desalination is equipped with a float that can float on the sea surface.

[0027] The first-stage, second-stage, and third-stage blades are staggered and installed around the pipe casing. From the top to the bottom of the pipe casing, the first-stage blades of the third layer, the second-stage blades of the second layer, and the third-stage blades of the first layer form a three-stage tower structure (more stages can be set with blades having the same internal structure as the first-stage, second-stage, and third-stage blades to form a multi-stage tower structure). Sunlight shines on the first-stage, second-stage, and third-stage blades through the concentrating glass, improving the utilization efficiency of solar energy.

[0028] Seawater fills the outer wall of the base and enters the inlet pipe, which is then introduced into the seawater pipeline through the suction body. The cooler seawater exchanges heat with the warmer water vapor in the condensation chamber through the lower wall of the condensation chamber, which accelerates the condensation rate of the water vapor and increases the freshwater production. At the same time, the seawater entering the system is preheated, which reduces heat loss and improves energy utilization.

[0029] The photocatalyst catalyzes the hot seawater seeping from the upper layer of the hydrophilic material to generate hydrogen and oxygen. The total molar mass of the photocatalytic product oxygen is greater than that of water vapor. The higher temperature oxygen flows downward into the hydrophilic material and exchanges heat with the lower temperature seawater in the hydrophilic material. The total molar mass of the photocatalytic product hydrogen is less than that of water vapor. It can act as a small molecule gas to promote the downward diffusion of the water vapor generated by the hydrophilic material into the condensation chamber, where it is condensed.

[0030] The inlet pipe, water intake body, pipe shell, freshwater pipe, hydrogen and oxygen gas pipe, seawater pipe, first-stage blade, photocatalyst, hydrophilic material, water-proof plate, condensation chamber, second-stage blade, third-stage blade, hydrophobic membrane, membrane separation device, oxygen-repellent membrane, valve, and oxygen-enriched gas pipe are all installed inside the focusing glass and base, forming an independent whole. The device draws in seawater or brackish water from the outside and independently completes seawater desalination and hydrogen and oxygen-enriched gas production within the focusing glass and base. The overall size of the device is determined by the base, making it adaptable to working on the sea surface and in pit environments. It is also easy to carry and can form a unitized production.

[0031] The hydrophobic and oxygen-repellent membranes can separate various mixed products in the condensation chamber, allowing fresh water to enter the fresh water pipeline and hydrogen-oxygen mixed gas to enter the hydrogen-oxygen gas pipeline. Hydrogen can be output downwards through the membrane separation device below the hydrogen-oxygen gas pipeline, and oxygen-enriched gas can be output from the oxygen-enriched gas pipeline by opening the valve.

[0032] Sunlight is focused by a concentrator and evenly illuminates the first, second, and third stage blades, providing both light and heat for the photocatalytic reaction and for the desalination of seawater by the hydrophilic material. Seawater absorbs heat within the hydrophilic material, forming hot and cold water flows in the upper and lower halves, respectively. Simultaneously, the hot water flows evaporate to generate water vapor. The photocatalyst catalyzes the hot water flowing from the top of the hydrophilic material to generate hydrogen and oxygen. Hydrogen, with a molar mass less than water vapor, promotes the downward diffusion of water vapor into the condensation chamber, while oxygen, with a molar mass greater than water vapor, moves downward into the hydrophilic material. The higher-temperature oxygen exchanges heat with the lower-temperature seawater within the material, increasing the base temperature of the seawater and accelerating the desalination rate. The water vapor, hydrogen, and oxygen then mix and enter the condensation chamber. The higher-temperature water vapor can exchange heat with the lower-temperature seawater in the seawater pipes below the condensation chamber through the condensation chamber walls, accelerating the evaporation process. The gas condensation rate increases freshwater production and raises the base temperature of seawater before it enters the hydrophilic material. Water vapor in the condensation chamber condenses into freshwater, which enters the freshwater pipe at the bottom of the condensation chamber. An oxygen-repellent membrane is installed near the condensation chamber inlet to prevent oxygen from entering. When the condensation chamber is half-filled with a hydrogen-oxygen mixture, the mixture can be discharged through the hydrogen-oxygen gas pipe inside the condensation chamber. The hydrogen-oxygen mixture flows downwards in the hydrogen-oxygen gas pipe and transfers heat through the pipe wall to the cooler seawater in the adjacent seawater pipe, further raising the base temperature of the seawater and improving the overall heat utilization efficiency of the device. When the hydrogen-oxygen mixture reaches the bottom of the hydrogen-oxygen gas pipe, the valve can be closed. At this time, through the action of the membrane separation device, high-purity hydrogen gas can be output from the bottom of the hydrogen-oxygen gas pipe. After a period of time, the valve is opened, and oxygen-enriched gas can be output from the oxygen-enriched gas pipe, achieving the goal of simultaneously generating freshwater, hydrogen, and oxygen-enriched gas.

[0033] Select some multi-fiber hydrophilic materials with strong affinity or capillary action for water, such as cotton or jute cloth, and connect one end to a seawater pipe. Under the capillary action of the fibers, seawater is drawn into the hydrophilic material, forming a uniform film, which facilitates the heat absorption and evaporation of seawater and improves the efficiency of seawater desalination.

[0034] The beneficial effects of this invention are:

[0035] The device has a low space occupancy rate, is easy to carry and install, and is highly flexible. It can be placed on the sea surface or in a pit filled with seawater. Multiple devices can also be combined into an array to improve the production output and efficiency of hydrogen and fresh water.

[0036] 2. It adopts a three-layer tower-shaped biomimetic structure. A light-concentrating glass is installed above the base to concentrate sunlight on the first-stage blade, the second-stage blade, and the third-stage blade, thereby increasing the light-receiving area of ​​the device. In addition, the seawater pipe is closely attached to the bottom of the condensation chamber. When the high-temperature water vapor in the condensation chamber condenses, it can transfer heat through the bottom wall of the condensation chamber to the lower-temperature seawater in the seawater pipe, thereby improving the utilization of the latent heat of water vapor condensation and achieving the goal of efficient utilization of solar thermal energy.

[0037] 3. In the first-stage, second-stage, and third-stage blades, the photocatalyst is in direct contact with the hydrophilic material. The photocatalyst generates hydrogen-oxygen composite gas through the water source provided by the hydrophilic material. Both the photocatalyst and the generated hydrogen-oxygen composite gas carry a certain amount of residual heat. Through structural design, the direct contact between the hydrophilic material and the photocatalyst can absorb this residual heat, thereby accelerating the rate of seawater evaporation.

[0038] 4. Seawater desalination and photocatalytic water reaction are coupled together. Seawater desalination can stabilize the efficiency of photocatalytic reaction. A high-temperature hydrogen-oxygen complex gas is generated below the photocatalyst. The hydrogen-oxygen complex gas diffuses downward and exchanges heat with the seawater in the hydrophilic material, ensuring the stability of the photocatalytic reaction environment temperature. At the same time, a gas flow circulation is formed to ensure the stability of the photocatalytic reaction environment pressure, thereby stabilizing the overall photocatalytic reaction efficiency and ensuring that the reaction efficiency does not decrease over time.

[0039] 5. In the hydrogen-oxygen gas pipeline that is closely connected to the seawater pipeline, the hydrogen-oxygen mixture flows downward, while the seawater in the seawater pipeline flows upward. The two form a countercurrent heat exchange, and the waste heat of the hydrogen-oxygen mixture can be absorbed by the seawater, achieving the purpose of efficient utilization of the waste heat of the hydrogen-oxygen mixture. At the same time, it increases the initial temperature of the seawater, accelerates seawater evaporation, and improves the efficiency of seawater desalination.

[0040] 6. By using hydrophobic membranes, oxygen-repellent membranes, and membrane separation devices, relatively pure fresh water and hydrogen can be obtained, as well as oxygen-enriched gas. Attached Figure Description

[0041] Figure 1 This is a schematic cross-sectional view of a biomimetic photocatalytic hydrogen production and simultaneous seawater desalination device.

[0042] Figure 2 A top view schematic diagram of a biomimetic photocatalytic hydrogen production and simultaneous seawater desalination device;

[0043] Figure 3 This is a schematic cross-sectional view of the first-stage blade, second-stage blade, and third-stage blade of a biomimetic photocatalytic hydrogen production and simultaneous seawater desalination device.

[0044] Figure 4This is a top view schematic diagram of the structure of the first-stage blade, the second-stage blade, and the third-stage blade of a biomimetic photocatalytic hydrogen production and simultaneous seawater desalination device.

[0045] Figure 5 This is a partially enlarged cross-sectional schematic diagram of a biomimetic photocatalytic hydrogen production and simultaneous seawater desalination device.

[0046] The components are as follows: 1-Concentrating glass, 2-Base, 3-Inlet pipe, 4-Water absorber, 5-Pipe shell, 6-Fresh water pipe, 7-Hydrogen and oxygen gas pipe, 8-Seawater pipe, 9-First-stage blade, 10-Photocatalyst, 11-Hydrophilic material, 12-Water barrier, 13-Condensation chamber, 14-Second-stage blade, 15-Third-stage blade, 16-Hydrophobic membrane, 17-Membrane separation device, 18-Oxygen-repellent membrane, 19-Valve, 20-Oxygen-enriched gas pipe, 21-Float. Detailed Implementation

[0047] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0048] As attached Figure 1 To be continued Figure 4 As shown, a biomimetic photocatalytic hydrogen production and simultaneous seawater desalination device includes a focusing glass 1, a base 2, a water inlet pipe 3, a water absorber 4, a pipe shell 5, a freshwater pipe 6, a hydrogen-oxygen gas pipe 7, a seawater pipe 8, a first-stage blade 9, a photocatalyst 10, a hydrophilic material 11, a water-separating plate 12, a condensation chamber 13, a second-stage blade 14, a third-stage blade 15, a hydrophobic membrane 16, a membrane separation device 17, an oxygen-repellent membrane 18, a valve 19, an oxygen-enriched gas pipe 20, and a float 21. The device is characterized in that the first-stage blade 9, the second-stage blade 14, and the third-stage blade 15 are installed from top to bottom on the outer wall of the pipe shell 5. The first-stage blade 9, the second-stage blade 14, and the third-stage blade 15 tilt upwards from the installation point of the pipe shell 5 towards the base 2, forming a tower-shaped biomimetic structure.

[0049] Photocatalyst 10 is installed on the inner top of the first-stage blade 9, the second-stage blade 14, and the third-stage blade 15, and the hydrophilic material 11 is adhered below the photocatalyst 10.

[0050] A condensation chamber 13 is installed on the bottom inner side of the first-stage blade 9, the second-stage blade 14, and the third-stage blade 15. A water-separating plate 12 is installed between the condensation chamber 13 and the hydrophilic material 11.

[0051] The water-blocking plate 12 can block the downward flow of seawater in the hydrophilic material 11, but allows water vapor to pass through;

[0052] The hydrophilic material 11 draws seawater from the seawater pipe 8. The seawater in the hydrophilic material 11 absorbs heat and rises in temperature by using the sunlight gathered by the concentrating glass 1. Hot seawater flow a and cold seawater flow b are formed in the upper and lower halves of the hydrophilic material 11, respectively. At the same time, hot seawater flow a evaporates to generate water vapor.

[0053] The condensation chamber 13 is located directly above the seawater pipe 8;

[0054] The hot seawater a in the upper part of the hydrophilic material 11 can permeate out of the hydrophilic material 11 and come into contact with the photocatalyst 10 above the hydrophilic material 11. The permeated hot seawater a is catalyzed by the photocatalyst 10 to generate a hydrogen-oxygen mixed gas e. The hydrogen-oxygen mixed gas e contains hydrogen c and oxygen d. Since the total molar mass of hydrogen c is less than that of water vapor e, it can act as a small molecule gas to promote the downward diffusion of the high-temperature water vapor e generated in the hydrophilic material 11 through the water-blocking plate 12 into the condensation chamber 13. The high-temperature water vapor e entering the condensation chamber 13 exchanges heat with the low-temperature seawater in the seawater pipe 8 through the chamber wall to accelerate the condensation of water vapor into fresh water. Its latent heat of condensation is used to increase the temperature of the seawater in the seawater pipe 8.

[0055] The oxygen d generated by the photocatalytic reaction, with a total molar mass greater than that of water vapor, enters the hydrophilic material 11. In the hydrophilic material 11, the high-temperature oxygen d mixes thoroughly with the cold seawater b and exchanges heat, raising the temperature of the cold seawater b and accelerating the conversion of the cold seawater b into the hot seawater a, thus improving the desalination efficiency. The hydrogen-oxygen mixed gas e diffuses downward into the condensation chamber 13, carrying away the heat from the photocatalyst 10. Subsequently, the hydrogen c and oxygen d generated by the photocatalyst 10 catalyzing the hot seawater a can fill the gas gap after the flow of the hydrogen-oxygen mixed gas e, forming a gas flow cycle. This ensures the temperature stability of the hydrophilic material 11 and the photocatalyst 10, as well as the stability of the photocatalytic reaction environment temperature, and the stability of the gas pressure around the photocatalyst 10, so that the seawater desalination efficiency and the photocatalytic reaction efficiency will not decrease due to changes in ambient temperature and pressure.

[0056] After the first product generation is completed, the condensation chamber 13 and the photocatalyst 10 form a cycle, simultaneously generating a hydrogen-oxygen mixed gas e and water vapor.

[0057] The outer casing 5 houses a freshwater pipe 6, a hydrogen-oxygen gas pipe 7, and a seawater pipe 8. The hydrogen-oxygen gas pipe 7 is fitted to the seawater pipe 8 on the inner side of the outer casing 5. The hydrogen-oxygen mixture e flowing downward in the hydrogen-oxygen gas pipe 7 exchanges heat with the seawater flowing upward in the seawater pipe 8 through the pipe wall, increasing the base temperature of the seawater in the seawater pipe 8. The lower inner side of the condensation chamber 13 in the first-stage blade 9, the second-stage blade 14, and the third-stage blade 15 is directly connected to the freshwater pipe 6, the hydrogen-oxygen gas pipe 7, the hydrophobic film 16, and the oxygen-phobic film 18. The first-stage blade 9, the second-stage blade 14, and the third-stage blade 15 have a V-shaped structure, with each stage of the blades installed alternately, so that sunlight can reach the upper surface of the blades. Even in the vertical direction, the lower blades, which are blocked by the upper blades, can still receive obliquely incident sunlight radially, improving the utilization rate of sunlight. The photocatalytic hydrogen production and simultaneous seawater desalination device is equipped with a float 21, which can float on the sea surface.

[0058] The first-stage blade 9, the second-stage blade 14, and the third-stage blade 15 are staggered and installed around the pipe shell 5, from the top to the bottom of the pipe shell 5. The first-stage blade 9 of the third layer, the second-stage blade 14 of the second layer, and the third-stage blade 15 of the first layer form a three-stage tower structure. More stages of blades can be set to form a multi-stage tower structure. Sunlight shines on the first-stage blade 9, the second-stage blade 14, and the third-stage blade 15 through the concentrating glass 1, increasing the area of ​​sunlight exposure.

[0059] Seawater fills the outer wall of the base 2 and enters the water inlet pipe 3. The seawater is then introduced into the seawater pipe 8 through the water suction body 4. The lower temperature seawater exchanges heat with the higher temperature water vapor in the condenser 13 through the lower wall of the condenser 13.

[0060] The first-stage blade 9, the second-stage blade 14, and the third-stage blade 15 all pass through the seawater pipe 8, utilizing capillary and siphon effects to transport seawater to the hydrophilic material 11. The hydrophilic material 11 is installed below the photocatalyst 10, and the hydrophilic material 11 is in direct contact with the photocatalyst 10. The photocatalyst 10 catalyzes the hot seawater a seeping from the upper layer of the hydrophilic material 11 to generate hydrogen c and oxygen d. The oxygen d, with a total molar mass greater than water vapor and a higher temperature, flows downward into the hydrophilic material 11 and exchanges heat with the lower-temperature seawater in the hydrophilic material 11. The hydrogen c, with a total molar mass less than water vapor, forces the water vapor generated by the hydrophilic material 11 to move downward into the condensation chamber 13.

[0061] The following components are installed within the focusing glass 1 and the base 2, forming an independent unit: 3. Water inlet pipe; 4. Water intake body; 5. Pipe shell; 6. Freshwater pipe; 7. Hydrogen and oxygen gas pipe; 8. Seawater pipe; 9. First-stage blade; 10. Photocatalyst; 11. Hydrophilic material; 12. Water separator; 13. Condensation chamber; 14. Second-stage blade; 15. Third-stage blade; 16. Hydrophobic membrane; 17. Membrane separation device; 18. Oxygen-enriched membrane; 19. Valve; and 20. Oxygen-enriched gas pipe. The device draws in seawater or brackish water from the outside and independently completes seawater desalination and the production of hydrogen and oxygen-enriched gas within the focusing glass 1 and the base 2. The overall size and specifications of the device are determined by the base 2, allowing it to adapt to working environments such as the sea surface and pits. It is also easy to carry and can form a modular production unit.

[0062] The hydrophobic membrane 16 and oxygen-repellent membrane 18 can separate the various mixed products in the condensation chamber 13, allowing fresh water to enter the fresh water pipe 6 and the hydrogen-oxygen mixed gas e to enter the hydrogen-oxygen gas pipe 7. Below the hydrogen-oxygen gas pipe 7, hydrogen gas c can be output downward through the membrane separation device 17, and oxygen-enriched gas can be output from the oxygen-enriched gas pipe 20 by opening the valve 19.

[0063] As attached Figure 2In one embodiment shown, sunlight is focused by the concentrating glass 1 and evenly illuminates the first-stage blade 9, the second-stage blade 14, and the third-stage blade 15, providing a light source and heat source for the photocatalyst 10's catalytic reaction and a heat source for the hydrophilic material 11 to desalinate seawater. Seawater in the hydrophilic material 11 absorbs heat to generate water vapor, forming hot and cold water currents. The hot water current moves upwards, causing the upper part of the hydrophilic material 11 to contain a larger amount of hot water current. Simultaneously, the hot water current evaporates to generate water vapor, and the photocatalyst 10 desalinates the water vapor that seeps from the top of the hydrophilic material 11. The hot seawater generates hydrogen and oxygen. Hydrogen, with a total molar mass less than water vapor, forces the water vapor in hydrophilic material 11 to move downwards into condensation chamber 13. Oxygen, with a total molar mass greater than water vapor, moves downwards into hydrophilic material 11. The higher-temperature oxygen exchanges heat with the lower-temperature seawater in hydrophilic material 11, increasing the base temperature of the seawater in hydrophilic material 11 and improving the seawater desalination rate. Water vapor, hydrogen, and oxygen mix together and enter condensation chamber 13. The higher-temperature water vapor can pass through the condensation chamber wall and the warmer seawater in the seawater pipe below condensation chamber 13. The system uses cooler seawater for heat exchange, accelerating the condensation of water vapor and increasing the base temperature of the seawater before it enters the hydrophilic material 11. Water vapor condenses into freshwater in the condensation chamber 13, which enters the freshwater pipe 6 at the bottom of the condensation chamber 13. An oxygen-repellent membrane 18 is installed near the inlet of the condensation chamber 13 to prevent oxygen from entering. When the condensation chamber is half-filled with a hydrogen-oxygen mixture, the mixture can be discharged through the hydrogen-oxygen gas pipe 7 inside the condensation chamber 13. The hydrogen-oxygen mixture flows downwards in the hydrogen-oxygen gas pipe 7 and transfers heat through the pipe wall to the cooler seawater in the seawater pipe 8 adjacent to the hydrogen-oxygen gas pipe 7, further increasing the base temperature of the seawater in the seawater pipe 8 and improving the overall heat utilization efficiency of the device. When the hydrogen-oxygen mixture e reaches the bottom of the hydrogen-oxygen gas pipe 7, the valve 19 can be closed. At this time, through the action of the membrane separation device 17, high-purity hydrogen can be output from the bottom of the hydrogen-oxygen gas pipe 7. After a period of time, the valve 19 is opened, and oxygen-enriched gas can be output from the oxygen-enriched gas pipe 20, achieving the goal of simultaneously generating freshwater, hydrogen, and oxygen-enriched gas.

[0064] Therefore, the description of the specific embodiments in this invention is not intended to limit the concept and scope of the invention. Any modifications and improvements made to the technical solution by those skilled in the art without departing from the technical solution of this invention will still fall within the protection scope of this invention.

Claims

1. A device for producing hydrogen and desalinating seawater simultaneously by using photocatalysis, comprising a light-gathering glass (1), a base (2), a water inlet pipe (3), a water-absorbing body (4), a pipe shell (5), a fresh water pipe (6), a hydrogen-oxygen gas pipe (7), a seawater pipe (8), a first-stage blade (9), a photocatalyst (10), a hydrophilic material (11), a water-blocking plate (12), a condensation cavity (13), a second-stage blade (14), a third-stage blade (15), a hydrophobic film (16), a membrane separation device (17), an oxygen-permeable film (18), a valve (19), an oxygen-rich gas pipe (20), and a float (21), characterized in that, The first stage blade (9), the second stage blade (14) and the third stage blade (15) are installed on the outer wall of the pipeline shell (5) from top to bottom, and are inclined upward from the installation position of the pipeline shell (5) to the base (2), forming a tower-shaped biomimetic structure; The first stage blade (9), the second stage blade (14) and the third stage blade (15) are installed on the outer wall of the pipeline shell (5) from top to bottom, and are inclined upward from the installation position of the pipeline shell (5) to the base (2), forming a tower-shaped biomimetic structure; The first stage blade (9), the second stage blade (14) and the third stage blade (15) are installed on the outer wall of the pipeline shell (5) from top to bottom, and are inclined upward from the installation position of the pipeline shell (5) to the base (2), forming a tower-shaped biomimetic structure; The water stop plate (12) blocks the downward flow of seawater in the hydrophilic material (11), but allows water vapor to pass through; The hydrophilic material (11) absorbs seawater from the seawater pipeline (8), and the seawater in the hydrophilic material (11) absorbs heat and warms up using sunlight concentrated by the light concentrating glass (1), forming hot seawater (a) and cold seawater (b) in the upper and lower parts of the hydrophilic material (11), respectively, while the hot seawater (a) evaporates to form water vapor; The condensing cavity (13) is tightly attached to the upper part of the seawater pipeline (8); The hot seawater (a) in the upper part of the hydrophilic material (11) seeps out of the hydrophilic material (11) and contacts the photocatalyst (10) above the hydrophilic material (11), and the seeped hot seawater (a) is catalyzed by the photocatalyst (10) to generate hydrogen-oxygen mixed gas (e), which contains hydrogen (c) and oxygen (d), wherein the unit molar mass of hydrogen (c) is less than that of water vapor (e), as a small molecule gas to promote the downward diffusion of high-temperature water vapor (e) generated in the hydrophilic material (11) through the water stop plate (12) into the condensing cavity (13), and the high-temperature water vapor (e) entering the condensing cavity (13) exchanges heat with the low-temperature seawater in the seawater pipeline (8) through the cavity wall to accelerate the condensation of water vapor into fresh water, and the latent heat of condensation is used to increase the temperature of the seawater in the seawater pipeline (8); The oxygen (d) with a unit molar mass greater than water vapor generated by the photocatalytic reaction goes down into the hydrophilic material (11), and the oxygen (d) with a higher temperature is fully mixed with the cold seawater (b) in the hydrophilic material (11) and exchanges heat, so as to increase the temperature of the cold seawater (b) and accelerate the speed of the cold seawater (b) to the hot seawater (a), thereby improving the desalination efficiency, and the hydrogen-oxygen mixed gas (e) diffuses downward into the condensation cavity (13) and takes away the heat in the photocatalyst (10), and then the hydrogen (c) generated by the photocatalyst (10) from the hot seawater (a) makes up for the gas vacancy after the flow of the hydrogen-oxygen mixed gas (e), so as to form a gas flow cycle, ensure the temperature stability of the hydrophilic material (11) and the photocatalyst (10) and the photocatalytic reaction environment, and ensure the stability of the air pressure around the photocatalyst (10), so that the seawater desalination efficiency and the photocatalytic reaction efficiency will not be reduced due to the change of the environmental temperature and pressure. The pipeline shell (5) is internally provided with a fresh water pipeline (6), a hydrogen-oxygen gas pipeline (7) and a seawater pipeline (8). The hydrogen-oxygen gas pipeline (7) is internally provided with the seawater pipeline (8) on the inner side of the pipeline shell (5), and the hydrogen-oxygen mixed gas (e) flowing downward in the hydrogen-oxygen gas pipeline (7) exchanges heat with the seawater flowing upward in the seawater pipeline (8) through the pipeline wall, so as to increase the basic temperature of the seawater in the seawater pipeline (8). The membrane separation device (17) is internally provided in the hydrogen-oxygen gas pipeline (7), wherein the membrane separation device (17) separates the hydrogen (c) and oxygen in the hydrogen-oxygen mixed gas (e). The oxygen-rich gas pipeline (20) is provided on the side of the hydrogen-oxygen gas pipeline (7) above the membrane separation device, and the valve (19) is internally provided in the oxygen-rich gas pipeline (20). The condensation cavity (13) in the first-stage blade (9), the second-stage blade (14) and the third-stage blade (15) is directly connected with the fresh water pipeline (6) through the oxygen-permeable membrane (18) below the inner side of the condensation cavity (13). The condensation cavity (13) in the first-stage blade (9), the second-stage blade (14) and the third-stage blade (15) is directly connected with the hydrogen-oxygen gas pipeline (7) through the water-permeable membrane (16) below the inner side of the condensation cavity (13). The first-stage blade (9), the second-stage blade (14) and the third-stage blade (15) are in V-shaped structure, and the blades are staggered, so that the sunlight can irradiate the upper surface of the blades, and the part of the lower blade blocked by the upper blade in the vertical direction can also obtain the sunlight obliquely incident from the radial direction, thereby improving the utilization rate of the sunlight. The device for producing hydrogen from seawater by photocatalysis and desalinating seawater simultaneously is provided with the floating body (21) floating on the sea surface.

2. The device according to claim 1, wherein The first-stage blade (9), the second-stage blade (14) and the third-stage blade (15) are staggered and arranged around the pipeline shell (5) to form a three-stage tower structure.

3. The device according to claim 2, wherein More blades with the same structure as the first-stage blade (9), the second-stage blade (14) and the third-stage blade (15) are arranged to form a multi-stage tower structure.

4. The device according to claim 1, wherein The seawater fills the outer wall of the base (2), the seawater enters the water inlet pipe (3) through the water suction body (4) and is introduced into the seawater pipeline (8), the seawater with lower temperature exchanges heat with the water vapor with higher temperature in the condensation cavity (13) through the cavity wall below the condensation cavity (13), the condensation rate of the water vapor is accelerated, the output of fresh water is improved, the seawater entering the system is preheated, the heat loss is reduced, and the energy utilization rate is improved.

5. The device according to claim 1, wherein The water inlet pipe (3), the water suction body (4), the pipeline shell (5), the fresh water pipeline (6), the hydrogen-oxygen gas pipeline (7), the seawater pipeline (8), the first-stage blade (9), the photocatalyst (10), the hydrophilic material (11), the water isolation plate (12), the condensation cavity (13), the second-stage blade (14), the third-stage blade (15), the hydrophobic film (16), the membrane separation device (17), the oxygen-permeation-resistant film (18), the valve (19) and the oxygen-enriched gas pipeline (20) are all installed in the light-condensing glass (1) and the base (2), form an independent whole, the device inhales seawater from the outside, independently completes seawater desalination and hydrogen and oxygen-enriched gas production in the light-condensing glass (1) and the base (2), and the size of the whole device is determined by the base (2).

6. The device according to claim 1, wherein The hydrophobic film (16) and the oxygen-permeation-resistant film (18) separate the mixed products in the condensation cavity (13), so that the fresh water enters the fresh water pipeline (6), the hydrogen-oxygen mixed gas (e) enters the hydrogen-oxygen gas pipeline (7), the hydrogen (c) is output downward through the membrane separation device (17) below the hydrogen-oxygen gas pipeline (7), and the oxygen-enriched gas is output from the oxygen-enriched gas pipeline (20) by opening the valve (19).

7. The method according to any one of claims 1-6, wherein the method is characterized in that, The method comprises: sunlight is converged by a light collecting glass (1) and uniformly irradiated on a first-stage blade (9), a second-stage blade (14) and a third-stage blade (15) to provide a light source and a heat source for catalytic reaction of a photocatalyst (10) and to provide a heat source for seawater desalination of a hydrophilic material (11), wherein seawater in the hydrophilic material (11) absorbs heat to form hot seawater (a) and cold seawater (b) in the upper half and the lower half of the hydrophilic material (11) respectively, and the hot seawater (a) is evaporated to generate water vapor; the photocatalyst (10) catalyzes the hot seawater (a) seeping out above the hydrophilic material (11) to generate hydrogen (c) and oxygen (d); the unit molar mass of the hydrogen (c) is smaller than that of the water vapor, and the hydrogen (c) promotes the downward diffusion of the water vapor in the hydrophilic material (11) into a condensation cavity (13); the unit molar mass of the oxygen (d) is greater than that of the water vapor, and the oxygen (d) moves downward into the hydrophilic material (11) to exchange heat with seawater in the hydrophilic material (11) at a lower temperature, thereby increasing the basic temperature of the seawater in the hydrophilic material (11) and the seawater desalination rate; the water vapor, the hydrogen (c) and the oxygen (d) are mixed together and enter the condensation cavity (13), wherein the water vapor at a higher temperature exchanges heat with seawater at a lower temperature in a seawater pipeline below the condensation cavity (13) through the wall of the condensation cavity to accelerate the condensation speed of the water vapor and increase the basic temperature of the seawater before entering the hydrophilic material (11); the water vapor in the condensation cavity (13) is condensed into fresh water and enters a fresh water pipeline (6) at the innermost lower part of the condensation cavity (13); an oxygen-permeation membrane (18) is installed at the entrance of the fresh water pipeline (6) near the condensation cavity (13) to block the oxygen (d) from entering; when the condensation cavity is filled with half of hydrogen-oxygen mixed gas (e), the hydrogen-oxygen mixed gas (e) is discharged through a hydrogen-oxygen gas pipeline (7) at the inner side of the condensation cavity (13); the hydrogen-oxygen mixed gas (e) flows downward in the hydrogen-oxygen gas pipeline (7) and transfers heat to seawater at a lower temperature in a seawater pipeline (8) close to the hydrogen-oxygen gas pipeline (7) through the wall of the hydrogen-oxygen gas pipeline (7), thereby increasing the basic temperature of the seawater in the seawater pipeline (8) and the heat utilization efficiency of the entire device; when the hydrogen-oxygen mixed gas (e) reaches below the hydrogen-oxygen gas pipeline (7), a valve (19) is closed; at this time, the hydrogen-oxygen gas pipeline (7) outputs hydrogen with a higher purity at the lowermost part through the action of a membrane separation device (17); after a period of time, the valve (19) is opened, and an oxygen-enriched gas pipeline (20) outputs oxygen-enriched gas at this time, thereby achieving the purpose of simultaneously generating fresh water, hydrogen and oxygen-enriched gas.

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