Catalyst structure capable of oxidizing hydrogen in air and hydrogen oxidation device

Abstract

To provide a catalytic structure capable of preventing a support material from collapsing due to moisture absorption, and converting hydrogen even in a non-high temperature environment in the catalyst structure for oxidizing and removing hydrogen in the air in a place where there is a possibility of the leakage of hydrogen.SOLUTION: The catalyst structure has a catalyst layer 12 disposed on a surface 111 of a base material 11, and the catalyst layer includes a carbon carrier 121, a plurality of catalyst particles 122 containing platinum metal or a platinum alloy, and a fluorine-based polymer 123. The catalyst particles are supported on a carbon carrier, and the carbon carrier is adhered to the surface of the base material by the fluorine-based polymer. The base material may have a flat plate, corrugated plate, honeycomb plate, or a thin plate wound in a spiral shape. The present invention further provides a hydrogen oxidation device, comprising the catalyst structure and a casing.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a catalytic structure, and in particular to a catalytic structure used for oxidizing hydrogen and a hydrogen oxidation device including said catalytic structure. [Background technology]

[0002] The International Energy Agency (IEA) predicts that in order to achieve the goal of substantially zero carbon dioxide emissions in 2050, the energy structure will be significantly adjusted and transformed, and hydrogen energy will receive increasing attention. Hydrogen can be used not only as a raw material for energy production, but also as an energy carrier. When power supply exceeds demand, hydrogen can be used to store surplus energy generated by renewable energy. In the manufacturing process of integrated circuits (ICs), hydrogen is also used as a carrier gas and hydrogen is generated by process reactions, so waste hydrogen is generated after the IC manufacturing process. However, hydrogen has flammable and explosive properties, so when the volume concentration of hydrogen in the air is 4.0% or more, it will cause an explosion if it encounters a fire source.

[0003] Therefore, hydrogen leak detectors are often installed in places where hydrogen may leak, such as places where hydrogen is used or produced. If hydrogen leaks and exceeds a preset safety value, an alarm is issued to initiate a chain reaction of safety measures, such as stopping the operation of the equipment, evacuating people and flammable materials on-site, operating exhaust fans, or using natural convection to continue suspended operations until the hydrogen concentration in the environment drops to a set safety value, or reusing the space. In other words, current safety measures can consume a large amount of resources and time. In addition, because hydrogen tends to concentrate in the ceiling and blind spots of the space, there are still areas where the hydrogen concentration does not fall within the safe range by relying only on convection and exhaust fans. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] China Patent Publication No. CN112271003A Summary of the Invention [Problem to be solved by the invention]

[0005] In order to solve the above problems, related research has been proposed to convert hydrogen into water with high safety. For example, the electric coupling heating method uses electric coupling heating to raise the temperature and make hydrogen reach the temperature required for oxidation, or a catalyst (e.g., palladium catalyst) is used to promote the conversion of hydrogen into water under low oxygen concentration. However, although the above-mentioned methods can reduce the hydrogen concentration in the space by converting hydrogen into water, they all need to be carried out at high temperatures. In addition, since the catalyst is usually fixed by sintering on a ceramic carrier, if the moisture content in the air is too high, the ceramic carrier is easily hydrolyzed and collapsed, which leads to the ineffectiveness of the catalyst structure. [Means for solving the problem]

[0006] In view of the technical deficiencies in the prior art, the objective of the present invention is to provide a catalytic structure capable of oxidizing hydrogen in air, which can convert hydrogen in a non-high temperature environment, thereby reducing the hydrogen concentration in a space.

[0007] Another object of the present invention is to provide a catalytic structure capable of oxidizing hydrogen in air, which can still effectively convert hydrogen in a high humidity environment, thus reducing the hydrogen concentration in the space.

[0008] In order to achieve the above object, the present invention provides a catalyst structure capable of oxidizing hydrogen in air. The catalyst structure includes a substrate having a first surface and a catalyst layer disposed on the first surface of the substrate. The catalyst layer includes a carbon support, a plurality of catalyst particles containing platinum metal or a platinum alloy, and a fluoropolymer. The plurality of catalyst particles are supported on the surface of the carbon support, and the carbon support is adhered to the first surface of the substrate by the fluoropolymer.

[0009] In the present invention, a structurally stable catalyst structure can be obtained by dispersing and attaching a carbon support carrying platinum metal by a fluoropolymer to the substrate, and the catalyst structure has strong oxidation resistance. Since the present invention uses catalyst particles containing platinum metal or a platinum alloy, the catalyst can be activated even in a non-high temperature environment (for example, 0°C to 100°C). In addition, since the present invention uses a carbon support, it is possible to avoid the susceptibility to moisture that occurs when using a ceramic support. Therefore, the catalyst structure capable of oxidizing hydrogen in the air according to the present invention can improve heat resistance and have better durability.

[0010] In some embodiments, the carbon support may include, but is not limited to, carbon black, carbon fiber, carbon nanotubes, activated carbon, mesoporous carbon, mesoporous carbon microspheres, graphite, graphene, or combinations thereof. Preferably, the carbon support is carbon black.

[0011] When the carbon support has a plurality of holes, the plurality of catalyst particles can be supported on the surface of the carbon support or dispersed within the holes. When the carbon support has a powder or granular structure (powder-like structure), the plurality of catalyst particles are supported on the surface of the carbon support, and each of the powder or granular carbon supports is adhered to each other by the fluoropolymer covering the surface of the carbon support. In other words, the fluoropolymer can cover a part or the whole of the surface of the carbon support.

[0012] When the carbon support has a powder or granular structure, the average particle size of the carbon support is preferably, but not limited to, 10 nanometers (nm) to 100 nm. The average particle size means the particle size corresponding to the cumulative particle size distribution percentage reaching 50%, and D 50 The average particle size of the carbon support is preferably 10 nm to 50 nm.

[0013] According to the present invention, the average particle size of the plurality of catalyst particles may be, but is not limited to, 1 nm to 50 nm. 50 It is preferable that the plurality of catalyst particles have an average particle size of 2 nm to 10 nm.

[0014] In some embodiments, the platinum alloy contained in the plurality of catalyst particles has a platinum content of 0.1 weight percent (wt%) to 99 wt%, and it is preferable that the platinum alloy has a platinum content of 1 wt% to 50 wt%.

[0015] In some embodiments, the plurality of catalyst particles further comprises palladium (Pd) metal, a palladium alloy, nickel (Ni) metal, a nickel alloy, cobalt (Co) metal, a cobalt alloy, ruthenium (Ru) metal, a ruthenium alloy, or a combination thereof.

[0016] In some embodiments, the fluoropolymer may include, but is not limited to, polytetrafluoroethene (PTFE), perfluorosulfonic acid resin (PFSA), poly(vinylidene fluoride), PVDF, or combinations thereof.

[0017] In some embodiments, the amount of the catalyst particles used is 0.1 wt % to 90 wt % based on the total weight of the carbon support and the catalyst particles in the catalyst layer.

[0018] In some embodiments, the amount of the carbon support used is 10 wt % to 99.9 wt % based on the total weight of the carbon support and the plurality of catalyst particles in the catalyst layer.

[0019] In some embodiments, the amount of the fluoropolymer used is 0.1 wt % to 50 wt % based on the total weight of the catalyst layer.

[0020] In some embodiments, the substrate material may include, but is not limited to, aluminum metal, aluminum alloy, copper metal, copper alloy, nickel metal, nickel alloy, stainless steel, carbon material, carbon fiber composite material, plastic, glass fiber composite material, or combinations thereof. Specifically, the carbon fiber composite material is a composite material combining carbon fiber and polymer resin, and the glass fiber composite material is a composite material combining glass fiber and polymer resin.

[0021] In some embodiments, the substrate geometry may include a solid plate shape, a plate shape with a plurality of through holes, a corrugated shape, a grid shape (fence shape), a lattice shape (mesh shape), a honeycomb shape, a foamed shape, or a combination thereof. For example, the substrate may be a porous or mesh material, such as a porous material such as nickel foam, aluminum foam, copper foam, carbon foam, etc. In other embodiments, the opposing ends of the substrate may be further extended to form two wings, which may secure the catalyst structure by a locking assembly.

[0022] According to the invention, the substrate has a first surface and a second surface, the second surface being opposite the first surface. In some embodiments, the substrate has the catalyst structure disposed only on the first surface. In other embodiments, the substrate further has another catalyst layer disposed on the second surface.

[0023] For example, the other catalyst layer on the second surface may be completely the same as the catalyst layer on the first surface, or the other catalyst layer on the second surface may be made of the same material as the catalyst layer on the first surface but have a different average thickness, or the other catalyst layer on the second surface may have the same carbon support as the catalyst layer on the first surface but a different type of catalyst particle, or the other catalyst layer on the second surface may have the same catalyst particles as the catalyst layer on the first surface but a different type of carbon support, but is not limited to the above.

[0024] In some embodiments, the catalyst structure has an average thickness of between 0.06 mm and 10.5 mm.

[0025] In some embodiments, the substrate has an average thickness of 0.05 mm to 10 mm.

[0026] In some embodiments, the medium layer has an average thickness of 0.01 mm to 0.5 mm.

[0027] In some embodiments, the catalytic structure of the present invention can be directly installed at the site where hydrogen processing is to be performed. For example, the two wings formed by the extension of the substrate of the catalytic structure are fixed to the wall by a locking assembly. The catalytic structure is also installed vertically on the ground. When the air passes through the catalytic structure, hydrogen contained in the air reacts with oxygen in the air to promote the production of water.

[0028] The catalyst structure of the present invention may be preferably placed in an environment with a temperature of 0° C. to 100° C. so as to promote the conversion of the hydrogen to water, but is not limited thereto.

[0029] The present invention is preferably applied to treating air containing hydrogen with a volume concentration of 5% or less and converting the hydrogen into water, thereby preventing disasters such as fires and explosions caused by hydrogen.

[0030] The present invention further provides a hydrogen oxidation device. The hydrogen oxidation device includes at least one of the catalyst structures and a casing having a storage space, a first gas flow section, and a second gas flow section that are in communication with each other. The storage space is located inside the casing, and the first gas flow section and the second gas flow section are installed at both ends of the storage space, respectively. The medium structure is installed in the storage space and is located between the first gas flow section and the second gas flow section.

[0031] In some embodiments, the at least one catalyst structure is a plurality of catalyst structures, each of which is spaced apart from one another. Specifically, the catalyst structures may be arranged in parallel with a space between them, or the media structures may be arranged in concentric circles with a space between them.

[0032] In some embodiments, the at least one catalyst structure may be generally spirally wound, with each cycle forming passages spaced apart from one another, and as the hydrogen-containing air spirals through the passages in the catalyst structure, the time the hydrogen-containing air passes through the catalyst structure may be extended, allowing the hydrogen oxidation reaction to occur more completely.

[0033] In some embodiments, the casing may have one or more openings only in the first gas flow section and the second gas flow section, respectively, or the entire casing may have a grid or mesh shape.

[0034] In some embodiments, gas is introduced from the first gas flow section and discharged from the second gas flow section. For example, the direction of the airflow introduced from the first gas flow section is the same as the direction of the airflow discharged from the second gas flow section, or the direction of the airflow introduced from the first gas flow section is perpendicular to the direction of the airflow discharged from the second gas flow section. In some other embodiments, gas flows in both directions between the first gas flow section and the second gas flow section.

[0035] In some embodiments, the catalytic structure is removably attached to the hydrogen oxidizer.

[0036] In some embodiments, the hydrogen oxidation device may further include a thermochromic assembly disposed on an outer surface of the casing and including a thermochromic dye, When hydrogen contained in air comes into contact with the catalytic structure in the hydrogen oxidation device, an oxidation reaction of the hydrogen occurs, the temperature of the hydrogen oxidation device increases, and the thermochromic assembly changes color to indicate this.

[0037] In some embodiments, the hydrogen oxidation device may further include a moisture sensing unit disposed on the outer surface of the casing, the moisture sensing unit including a dye that changes color after absorbing moisture. When hydrogen contained in air comes into contact with the catalytic structure in the hydrogen oxidation device, the hydrogen undergoes an oxidation reaction to generate moisture, and the moisture sensing unit can indicate this by changing color. Preferably, the moisture sensing unit is disposed on an upper surface of the casing, the upper surface may be perpendicular to the first gas flow section and the second gas flow section, or the upper surface may be a part of the second gas flow section. That is, when the installation of the hydrogen oxidation device is completed, the moisture sensing unit is located above the casing.

[0038] In some embodiments, the hydrogen oxidation device can be used together with a hydrogen sensing unit. The hydrogen sensing unit is installed outside the casing. The hydrogen sensing unit has a dye that changes color after absorbing hydrogen. When hydrogen comes into contact with the hydrogen oxidation device, the hydrogen sensing unit can indicate this by changing color. The hydrogen sensing unit is preferably installed correspondingly above the hydrogen oxidation device.

[0039] In some embodiments, since the hydrogen oxidation reaction is an exothermic reaction, the hydrogen oxidation device may further include a temperature detector disposed on the outer surface of the casing, which may generate an alarm when the temperature of the hydrogen oxidation device is too high.

[0040] In some embodiments, the hydrogen oxidation device is suitable for installation in an enclosed or semi-open space where a small amount of hydrogen may be generated or leaked, such as, but not limited to, a lead-acid battery charging room or a hydrogen cylinder cabinet, a nuclear power plant, etc. For example, the hydrogen oxidation device is installed in an upper layer within the space.

[0041] In some embodiments, the hydrogen oxidation device may further include a fastening assembly, which may include, but is not limited to, a magnetic assembly, a buckle or locking member, or the like.

[0042] According to the present invention, the hydrogen oxidation device may be placed in an environment with a temperature of 0° C. to 100° C., but is not limited thereto. [Brief description of the drawings]

[0043] [Figure 1] FIG. 2 is a schematic side cross-sectional view of the catalyst structure of Example 1. [Diagram 2] FIG. 2 is a schematic diagram of the catalyst structure of Example 2. [Diagram 3] FIG. 11 is a schematic perspective view of a hydrogen oxidation device according to a third embodiment. [Figure 4] FIG. 11 is a schematic perspective view of a hydrogen oxidation device according to a fourth embodiment. [Diagram 5] FIG. 11 is a schematic perspective view of the hydrogen oxidation device of Example 4 as viewed from another angle. [Figure 6] FIG. 11 is a schematic perspective view of a hydrogen oxidation device according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] Hereinafter, the embodiments of the present invention will be described by enumerating several examples. In the description of the present invention, the directions or positional relationships indicated by "center", "upper", "lower", "ceiling", "bottom", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, and are merely for the purpose of easily explaining the present invention, and do not mean or suggest that the mentioned device or assembly has a specific direction and must be constructed and operated in a specific direction.

[0045] <Catalyst structure of Example 1> As shown in FIG. 1, the catalyst structure 10 of this embodiment includes a single catalyst layer 12. That is, the catalyst structure 10 includes a substrate 11 and a catalyst layer 12. The substrate 11 has a first surface 111 and a second surface 112. The catalyst layer 12 is disposed on the first surface 111 of the substrate 11. The catalyst layer 12 includes a carbon support 121, a plurality of catalyst particles 122, and a fluoropolymer 123. The plurality of catalyst particles 122 are supported on the surface of the carbon support 121, and the fluoropolymer 123 covers a portion of the surface of the carbon support 121.

[0046] The material of the substrate 11 is a glass fiber composite material. The average thickness of the substrate 11 is 0.2 mm. The average thickness of the catalyst layer 12 is 0.05 mm. In the catalyst layer 12, the carbon support 121 is made of powdered or granular carbon black, and the average particle size of the carbon black is 30 nm. The catalyst particles 122 include platinum metal. The average particle size of the catalyst particles 122 is less than 10 nm. The fluorine-based polymer 123 is PFSA. The fluorine-based polymer 123 covers the surface of the powdered or granular carbon support 121, and not only bonds the powdered or granular carbon support 121 to each other, but also adheres the powdered or granular carbon support 121 to the first surface 111 of the substrate 11.

[0047] <Catalyst structure of Example 2> The catalyst structure 10 of this embodiment includes a substrate 11 and two catalyst layers 12. The catalyst structure 10 shown in FIG. 2 will be described in detail. The catalyst structure 10 includes a flat substrate 11 and two catalyst layers 12. The substrate 11 has a first surface 111 and a second surface 112 facing each other. One catalyst layer 12 is disposed on the first surface 111 of the substrate 11, and the other catalyst layer 12 is disposed on the second surface 112 of the substrate 11. That is, the substrate 11 is disposed between the two catalyst layers 12. The two catalyst layers 12 have the same material and average thickness. The material selection and average thickness of the substrate 11 and the catalyst layer 12 in this embodiment are the same as those of the substrate 11 and the catalyst layer 12 in Example 1.

[0048] <Hydrogen oxidation device of Example 3> As shown in Fig. 3, the hydrogen oxidation device 1 of this embodiment includes a plurality of catalyst structures 10 and a box-shaped casing 20. The casing 20 has a storage space 201, a first gas circulation section 202, and a second gas circulation section 203 that are in communication with each other. The storage space 201 is located inside the casing 20. The first gas circulation section 202 and the second gas circulation section 203 are respectively installed at opposite ends of the storage space 201. The plurality of catalyst structures 10 are inserted and installed in the storage space 201, and are located between the first gas circulation section 202 and the second gas circulation section 203.

[0049] The first gas flow section 202 and the second gas flow section 203 each have two rectangular openings. Each catalyst structure 10 is made of the same material as the catalyst structure 10 of Example 2, and the only difference is that the multiple catalyst structures 10 included in the hydrogen oxidation device 1 of this example further have multiple through holes. The multiple catalyst structures 10 contain a total of 0.672 grams of platinum metal. The multiple catalyst structures 10 are arranged in parallel with a gap between them. Each catalyst structure 10 is flat, and each flat plate has multiple through holes. After the hydrogen-containing air is introduced from the first gas flow section 202 into the hydrogen oxidation device 1, the hydrogen-containing air can pass through the multiple catalyst structures 10 while maintaining the same airflow direction, and is discharged from the second gas flow section 202. When hydrogen comes into contact with the catalyst structure 10, it can carry out an oxidation reaction, so that the hydrogen content in the hydrogen-containing air can be reduced.

[0050] <Hydrogen oxidation test> First, a hydrogen concentration detector with a detection limit of 10,000 ppm is prepared, and the hydrogen concentration detector is placed in a space that does not contain hydrogen and has an ambient temperature of 10° C. to 15° C. Then, hydrogen is introduced into the space at an air flow rate of 1.2 liters per minute (1.2 L / min). After continuously injecting hydrogen for 320 seconds, the hydrogen concentration in the space reaches the detection limit (i.e., 10,000 ppm).

[0051] In addition, the hydrogen oxidation device of Example 3 is placed in the same space where the ambient temperature is 10°C to 15°C and does not contain hydrogen. Similarly, hydrogen is introduced into the space in the same manner as above, and hydrogen is continuously injected for 370 seconds, and the hydrogen concentration in the space reaches a maximum value of 8150 ppm. Thereafter, the hydrogen concentration in the space begins to decrease, and when hydrogen is continuously injected for 900 seconds, the hydrogen concentration in the space is balanced. The hydrogen concentration at this time is 4500 ppm. As can be seen from the above, the hydrogen oxidation device of the present invention can indeed promote the hydrogen oxidation reaction in a non-high temperature (e.g., room temperature) environment and reduce the hydrogen concentration in the space.

[0052] <Hydrogen oxidation device of Example 4> As shown in FIG. 4 and FIG. 5, the hydrogen oxidation device 1 of this embodiment includes a catalyst structure 10 and a casing 20. The casing 20 is formed surrounded by the mesh-like outer peripheral surface of a hollow cylinder, and the openwork ceiling surface perpendicular to the outer peripheral surface and the bottom surface having a plurality of circular holes are the second gas circulation section 203 and the first gas circulation section 202 of the casing 20, respectively. The mesh-like inner peripheral surface of the hollow cylinder surrounds and forms the storage space 201. That is, the casing 20 has the storage space 201, the first gas circulation section 202, and the second gas circulation section 203, which are in communication with each other. The storage space 201 is located inside the casing 20. The first gas circulation section 202 and the second gas circulation section 203 are installed at both opposing ends of the storage space 201, respectively. In addition, the catalyst structure 10 is installed in the storage space 201 and is located between the first gas circulation section 202 and the second gas circulation section 203.

[0053] The catalyst structure 10 has a thin sheet-like shape. The entire catalyst structure 10 is spirally wound, and each cycle is spaced apart from each other to form an air flow passage for hydrogen-containing air. The catalyst structure 10 of this embodiment has the same material as the catalyst structure 10 of embodiment 2.

[0054] <Hydrogen oxidation device of Example 5> As shown in FIG. 6, the hydrogen oxidation device 1 of this embodiment includes a casing 20 and two catalyst structures 10. The hydrogen oxidation device 1 of this embodiment has the same casing 20 as the hydrogen oxidation device 1 of Example 4, the entire catalyst structure 10 is wound in a spiral manner and installed in the receiving space 201, and the material type of the catalyst structure 10 is also the same. The main difference between the hydrogen oxidation device 1 of this embodiment and the hydrogen oxidation device 1 of Example 4 is that the hydrogen oxidation device 1 of this embodiment has two catalyst structures 10, one of which has the same geometric structure as the catalyst structure 10 of Example 4, while the other catalyst structure 10 has a different geometric structure from the catalyst structure 10 of Example 4. Specifically, the other catalyst structure 10 is a thin corrugated plate, which is sandwiched between two cycles of the thin sheet-like catalyst structure 10.

[0055] As described above, the catalyst structure of the present invention can certainly promote the oxidation reaction of hydrogen in a non-high temperature (e.g., room temperature) environment, and therefore can reduce the hydrogen concentration in the space in which the catalyst structure is installed. This can prevent hydrogen explosions and ensure the safety of the space. In addition, the catalyst structure of the present invention uses a carbon support instead of the conventional ceramic support, which can prevent the catalyst structure from being affected by moisture, improve the heat resistance and moisture resistance of the catalyst structure, and provide better durability. Therefore, a hydrogen oxidation device including the catalyst structure can be applied to different spatial environments, and further has the potential for commercial product development.

Claims

1. A catalytic structure capable of oxidizing hydrogen in air, a substrate having a first surface; a catalyst layer disposed on the first surface of the substrate; The catalyst layer is A carbon support; a plurality of catalyst particles containing platinum metal or a platinum alloy; and a fluorine-based polymer, A catalyst structure, characterized in that the plurality of catalyst particles are supported on a surface of the carbon support, and the carbon support is adhered to the first surface of the substrate by the fluoropolymer.

2. The catalyst structure according to claim 1, wherein the plurality of catalyst particles have an average particle size of 1 nm to 50 nm.

3. 10. The catalyst structure of claim 1, wherein the plurality of catalyst particles further comprises palladium metal, palladium alloy, nickel metal, nickel alloy, cobalt metal, cobalt alloy, ruthenium metal, ruthenium alloy, or combinations thereof.

4. 2. The catalyst structure of claim 1, wherein the carbon support comprises carbon black, carbon fiber, carbon nanotubes, activated carbon, mesoporous carbon, mesoporous carbon microspheres, graphite, graphene, or a combination thereof.

5. 2. The catalyst structure according to claim 1, wherein the amount of the catalyst particles is 0.1% by weight to 90% by weight based on the total weight of the carbon support and the catalyst particles in the catalyst layer.

6. The catalyst structure according to any one of claims 1 to 5, characterized in that the geometric form of the substrate includes a solid flat plate shape, a flat plate shape with a plurality of through holes, a wave shape, a grid shape, a lattice shape, a honeycomb shape, a foamed porous shape, or a combination thereof.

7. The catalyst structure according to any one of claims 1 to 5, characterized in that the substrate has a second surface, the second surface facing the first surface, and another catalyst layer is provided on the second surface, the another catalyst layer having the same material as the catalyst layer provided on the first surface.

8. At least one catalyst structure according to any one of claims 1 to 5; a casing having a storage space, a first gas flow section, and a second gas flow section, the storage space and the first gas flow section being in communication with each other; the storage space is located inside the casing, and the first gas circulation part and the second gas circulation part are respectively installed at both ends of the storage space, The hydrogen oxidation device is characterized in that the catalyst structure is installed in the accommodation space and is located between the first gas flow section and the second gas flow section.

9. 10. The hydrogen oxidation apparatus of claim 8, wherein the at least one catalyst structure is a plurality of catalyst structures, each of which is spaced apart from the others.

10. 10. The hydrogen oxidation device of claim 8, wherein the at least one catalytic structure is spirally wound.

11. 9. The hydrogen oxidation device of claim 8, further comprising a thermochromic assembly disposed on an outer surface of the casing and including a thermochromic dye.

12. 9. The hydrogen oxidation device according to claim 8, further comprising a moisture sensing unit disposed on an outer surface of the casing, the moisture sensing unit including a dye that changes color after absorbing moisture.

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