Hydrogen production apparatus
The integrated hydrogen production apparatus addresses inefficiencies in separate-step methods by combining laser-induced reduction, separation, and hydrogen generation, achieving high productivity and efficiency with continuous processes and resource conservation.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2026-06-18
AI Technical Summary
Conventional hydrogen production methods involving separate steps for iron oxide reduction and oxidation are inefficient and lack industrial productivity.
A hydrogen production apparatus that integrates laser-induced reduction of metal oxide in solution, separation and transport of reduced metal, hydrogen generation through metal-water reaction, and hydrogen recovery, with optional metal oxide resupply, enabling continuous processes.
Facilitates highly productive and efficient hydrogen production with reduced metal activity loss and material reuse, enhancing sustainability and resource efficiency.
Smart Images
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Abstract
Description
Hydrogen production equipment
[0001] This disclosure relates to a hydrogen production apparatus.
[0002] Technologies that produce hydrogen, which does not emit carbon dioxide when burned, are attracting attention as a technology that could help solve the problems of global warming and the depletion of fossil fuels. In conventional technology, iron oxide particles are dispersed in a liquid, the iron oxide is reduced by laser irradiation to produce iron, and the produced iron is reacted (oxidized) with water (water vapor) to produce hydrogen (see, for example, Non-Patent Document 1).
[0003] "Hydrogen Production Using Reduced-Iron Nanoparticles by Laser Ablation in Liquids" ISRN Renewable Energy, Article ID: 827681 (2013)
[0004] However, in the hydrogen production method described in Non-Patent Document 1, the reduction process of iron oxide (iron production process) and the oxidation process of iron (hydrogen production process) are carried out as separate steps by separate devices, which presents challenges in terms of productivity and efficiency from an industrial standpoint.
[0005] This disclosure is made in view of the above points and aims to provide a hydrogen generation device that enables highly productive and efficient hydrogen production.
[0006] A hydrogen production apparatus according to one aspect of the present disclosure includes means for reducing a metal oxide in a solution by irradiating it with laser light; means for separating and transporting the reduced metal; means for generating hydrogen by reacting the reduced metal with water; and means for recovering the generated hydrogen.
[0007] According to this disclosure, it is possible to provide a hydrogen production apparatus that enables highly productive and efficient hydrogen production.
[0008] This figure shows an example of a hydrogen production apparatus according to this embodiment. This figure shows the reaction system proceeding in the hydrogen production apparatus according to this embodiment.
[0009] Embodiments of the present invention will be described below with reference to the drawings. The embodiments described below are merely examples, and the embodiments to which the present invention is applied are not limited to the embodiments described below.
[0010] Figure 1 shows an example of a hydrogen production apparatus according to this embodiment. The hydrogen production apparatus 1 shown in Figure 1 includes a metal oxide reduction means 10, a metal separation and transport means 20, a hydrogen generation means 30, a hydrogen recovery means 40, and a metal oxide recovery and resupply means 50.
[0011] Figure 2 shows the reaction system proceeding in the hydrogen production apparatus according to this embodiment. As shown in Figure 2, by irradiating metal oxide MO in solution S with laser light L, the metal oxide MO is reduced to obtain metal M. The reduced metal M is then treated with water (H ２ By reacting with O), metal M is oxidized to produce metal oxide MO, and water is reduced to hydrogen (H ２ ) is generated.
[0012] The metal M can be appropriately selected depending on the purpose, and examples include Mg, Al, Fe, Co, Ni, Mo, and W. The metal oxide MO can be appropriately selected from oxides corresponding to metal M. Among these, from the viewpoint of safety and availability, it is preferable that metal M is iron (Fe) and metal oxide MO is iron oxide. Here, the metal oxide MO corresponding to metal M can be appropriately selected according to the valence of the target metal. Examples of iron oxides include iron(II) oxide (FeO) and iron(II,III) oxide (Fe). ３ O ４ , iron(III) oxide Fe ２ O ３ These are some examples.
[0013] The metal oxide reduction means 10 is a means for reducing metal oxide MO in solution S by irradiating it with laser light L, and comprises a container 11 for containing solution S and metal oxide MO, a laser light source 12 for irradiating the metal oxide MO in solution S with laser light L, and a stirring unit 13 for stirring the metal oxide MO in solution S. The metal oxide reduction means 10 reduces the metal oxide MO by irradiating it with laser light while stirring the metal oxide MO in solution S, thereby obtaining metal M.
[0014] Examples of solution S include water, organic solvents such as ethanol, and mixed solvents thereof. The content of metal oxide MO in solution S can be appropriately selected depending on the container shape, stirring conditions, laser irradiation conditions, etc., and examples include 5 mg / mL to 100 mg / mL.
[0015] The container 11 is capable of containing the solution S and metal oxide MO, and has a region through which laser light L can pass. For example, a transparent container can be used as the container 11. The shape of the container 11 can be appropriately selected according to stirring conditions, laser irradiation conditions, etc., so that the laser can be efficiently irradiated onto each particle of metal oxide MO. Examples include a pear-shaped flask and a glass container with a laser-transmitting region diameter of 10 mm to 30 mm.
[0016] For example, an infrared pulsed laser can be used as the laser light source 12. The conditions for the laser light source 12 and the irradiated laser light L can be appropriately selected depending on the metal oxide MO used, for example, Fe ２ O ３ In contrast, a high repetition rate pulsed fiber laser can be used. Methods for irradiating the metal oxide MO in solution S with laser light L include irradiating the laser light from the side of the container, or irradiating the laser light from the top and / or bottom of the container. Furthermore, the efficiency of laser irradiation can be increased by methods such as rotating the container while irradiating with laser light, or scanning the laser light while irradiating.
[0017] There are no particular restrictions on the method for confirming that metal M has been obtained by the reduction of metal oxide MO. For example, its reducing ability may be estimated from its hydrogen-generating ability, or the presence of metal M may be identified by X-ray diffraction.
[0018] Regarding the particle size of metal M, from the viewpoint of improving the reaction efficiency with water, it is preferable to make the metal particles finer and increase the surface area. For example, the volume-average particle size measured by laser diffraction scattering is preferably 10 nm to 1 μm, and more preferably 10 nm to 500 nm. The particle size of metal M obtained by reduction can be reduced by irradiating metal oxide MO with laser light L. The particle size of metal oxide MO may be 1 μm to 50 μm in volume-average particle size measured by laser diffraction scattering.
[0019] The stirring unit 13 is not particularly limited as long as it can stir the metal oxide MO in the solution S, and can be appropriately selected. For example, a stirrer, stirring rod, ultrasonic vibration, etc., can be used. The stirring conditions can be appropriately selected so that the laser is efficiently irradiated onto each particle of metal oxide MO.
[0020] The metal separation and transport means 20 is a means for separating and transporting the reduced metal M, and includes a separation unit 21 for separating the reduced metal M in the solution S, a transport unit 22 for transporting the separated metal M, and further includes a drying unit 23 for drying the separated metal M as needed.
[0021] The separation unit 21 is, for example, a filter, and by filtering the solution S after laser irradiation, the reduced metal M and the solution S can be separated. The transport unit 22 can be, for example, a transport belt, a transport stage, or a transport container, and can transport the filter containing the filtered metal M or the transport container containing the filter. The metal M is then transported to the reaction vessel 31 in the subsequent hydrogen generation means 30. The metal M may be dried during transport; for example, a drying unit can be installed on the transport path, and the metal M can be dried by passing it through a hot zone while flowing a gas such as nitrogen. On the other hand, the solution S filtered by the filter may be recovered and returned to the container 11 for reuse.
[0022] The hydrogen generation means 30 is a means for generating hydrogen by reacting a reduced metal M with water, and includes a reaction vessel 31 for reacting the reduced metal with water, and a heating unit 32 for heating the reaction vessel 31.
[0023] The reaction vessel 31 accommodates the metal M conveyed from the metal separation and conveyance means 20. For example, it has a water supply port and a hydrogen discharge port, can react the supplied water with the metal M, and discharge the generated hydrogen. As the reaction vessel 31, a vessel having heat resistance at the reaction temperature and no reactivity with water can be used. For example, an aluminum vessel can be used. The heating unit 32 is, for example, a heater and can heat the reaction vessel 31 and the reaction system to the reaction temperature. The reaction temperature can be appropriately selected according to the metal M used. When the metal M is iron, it is 250°C to 500°C, preferably 350°C to 450°C. The water presented in the reaction may be water vapor. Here, as shown in the metal oxidation reaction (right side) of FIG. 2, by reacting the reduced metal M with water (H ２ O), the metal M is oxidized to form the metal oxide MO, and at the same time, the water is reduced to generate hydrogen (H ２ ).
[0024] The hydrogen recovery means 40 is a means for recovering the generated hydrogen. It has a hydrogen recovery container 41 capable of accommodating hydrogen, and can recover and bottle the generated hydrogen through a pipe connected to the hydrogen discharge port of the reaction vessel 31. A filter (for example, a polymer membrane) selectively permeable to hydrogen may be provided in the pipe and / or the opening of the hydrogen recovery container 41, or it may be recovered by the water displacement method. As the hydrogen recovery container 41, for example, a known hydrogen tank, a high-pressure hydrogen tank, a hydrogen storage alloy, etc. can be used. The hydrogen recovered in the hydrogen recovery container 41 can be, for example, further filled into a high-pressure hydrogen tank at high pressure for storage and transportation.
[0025] The hydrogen production apparatus of this embodiment preferably has a metal oxide recovery and resupply means 50, as in the hydrogen production apparatus 1. The metal oxide recovery and resupply means 50 is a means for recovering metal (metal oxide MO) that has been oxidized by reaction with water and resupplying it into the solution S, and includes a metal oxide recovery unit 51 that recovers the metal oxide MO produced by the reaction with water from the reaction vessel 31, and a metal oxide supply unit 52 that supplies the recovered metal oxide MO to the container 11 of the metal oxide reduction means 10. The metal oxide recovery unit 51 and the metal oxide supply unit 52 may be integrated. The metal oxide supply unit 52 may supply only metal oxide MO to the container 11, or it may suspend the metal oxide MO in the solution S filtered in the separation unit 21 and then supply it to the container 11, or it may be configured to further wash the metal oxide supply unit 52 with the solution S or pure water after supplying the metal oxide MO to the container 11.
[0026] According to the hydrogen production apparatus of this embodiment, the metal oxide reduction process and the hydrogen production process by oxidation of the generated metal can be carried out continuously within a single apparatus, resulting in high productivity and efficient hydrogen production. Furthermore, since the highly active reduced metal (metal M) obtained by the metal oxide reduction means can be immediately supplied to the hydrogen production means by the metal separation and transport means, the decrease in metal activity due to long-term storage or transport can be reduced, resulting in high productivity and efficient hydrogen production. In addition, if a metal oxide recovery and resupply means is provided to resupply the metal oxide generated by hydrogen production back into the solution, even more efficient hydrogen production can be achieved. Moreover, materials can be reused, enabling sustainability and resource conservation.
[0027] The following additional information is disclosed regarding the embodiments described above.
[0028] <Notes> (Note 1) A hydrogen production apparatus characterized by comprising: means for reducing a metal oxide in a solution by irradiating it with laser light; means for separating and transporting the reduced metal; means for generating hydrogen by reacting the reduced metal with water; and means for recovering the generated hydrogen. (Note 2) The hydrogen production apparatus according to Note 1, wherein the metal is iron and the metal oxide is iron oxide. (Note 3) The hydrogen production apparatus according to Note 1 or 2, further comprising means for recovering the metal that has been oxidized by reacting with water and resupplying it into the solution.
[0029] The present invention is not limited to the embodiments specifically disclosed above, and various modifications, changes, and combinations with known technologies are possible without departing from the scope of the claims.
[0030] 1 Hydrogen production apparatus 10 Metal oxide reduction means 11 Container 12 Laser light source 13 Stirring unit 20 Metal separation and transport means 21 Separation unit 22 Transport unit 23 Drying unit 30 Hydrogen generation means 31 Reaction vessel 32 Heating unit 40 Hydrogen recovery means 41 Hydrogen recovery container 50 Metal oxide recovery and resupply means 51 Metal oxide recovery unit 52 Metal oxide supply unit L Laser light MO Metal oxide M Metal S Solution
Claims
1. A hydrogen production apparatus comprising: means for reducing a metal oxide in a solution by irradiating it with laser light; means for separating and transporting the reduced metal; means for generating hydrogen by reacting the reduced metal with water; and means for recovering the generated hydrogen.
2. The hydrogen production apparatus according to claim 1, wherein the metal is iron and the metal oxide is iron oxide.
3. The hydrogen production apparatus according to claim 1 or 2, further comprising means for recovering the metal that has been oxidized by reaction with the water and resupplying it into the solution.