Hydrogen slow-release composite material, hydrogen slow-release device and hydrogen slow-release method based on moisture self-regulation

Abstract

The invention discloses a hydrogen slow-release composite material based on moisture self-regulation and a hydrogen slow-release device and method.The composite material comprises, by mass, 15-25 wt% of a hydrogen production component, and the hydrogen production component comprises a solid hydrogen production material and is used for reacting with water to release hydrogen; the water absorption component is used for absorbing and retaining water; 5-25 wt% of a water-consuming component for reacting with water to consume water; wherein the total solid water amount corresponding to the water absorption component and the water consumption component is greater than the theoretical water amount required by complete reaction of the hydrogen production component; the raw materials are mixed, compacted and molded to obtain the hydrogen slow-release composite material. When external water supply fluctuates, the material system can spontaneously adjust moisture entering a reaction environment, so that the effective water consumption participating in the hydrolysis reaction of magnesium hydride is more stable, the hydrogen production process is easier to maintain a slow and stable release state, and the dependence on high-precision external water supply equipment and complex control links is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydrogen production, and particularly relates to a hydrogen slow-release composite based on water self-regulation, a hydrogen slow-release device and a method. BACKGROUND

[0002] The hydrogen supply route of the solid-state hydrogen production material and water hydrolysis reaction to release hydrogen has been used in distributed hydrogen supply, portable hydrogen terminal and other scenes because of the relative ease of raw material storage, fast response to start and stop, and compact device structure. The solid-state hydrogen production system represented by magnesium-based hydrogen production materials (such as magnesium, magnesium hydride and their composites) can react with water to produce hydrogen at room temperature, but the reaction process is extremely sensitive to water supply, and often shows the characteristics that changes in water quantity, temperature and interface state can cause significant fluctuations in hydrogen production rate, making it difficult to maintain stable output in actual use.

[0003] The existing hydrolysis hydrogen supply system usually relies on an external water supply unit for quantitative water supply or intermittent drop to control the reaction rate. However, in actual application, factors such as flow fluctuation, vibration and shaking, posture change, residual water and back infiltration of the water supply unit can cause short-term enrichment of free water in the reaction cavity, leading to sudden increase in hydrogen production rate and local heat release concentration, and then causing uneven gas output, decreased reaction efficiency or local material clogging and other problems. On the other hand, when the hydrogen supply needs to be stopped or the water supply needs to be stopped, the residual free water in the reaction cavity may continue to react with the hydrogen production material, making it difficult to stop hydrogen production in time, affecting controllable start and stop, and possibly causing adverse effects on safety and maintenance.

[0004] To improve controllability, existing technologies attempt to constrain from the material or structure aspect, such as changing the shape of the hydrogen production material, introducing catalytic or inhibiting components, using a coating layer or a separation layer, setting a porous medium or a membrane structure to regulate water flux, or increasing complex valve control, metering and feedback control on the device level to stabilize hydrogen supply. The above-mentioned solutions can alleviate fluctuations under certain conditions, but generally have the disadvantages of high dependence on external control, increased structural complexity, limited adaptability to different working conditions, etc. Especially in the water stop condition, if there is no effective reduction mechanism for the free water in the reaction system, the reaction may continue after the water is stopped, which fundamentally limits the application of hydrolysis hydrogen supply in portable and long-term stable output scenarios.

[0005] For example, in the invention CN108059127A, a hydrolysis hydrogen production aluminum alloy reaction hydrogen supply device and its use method are disclosed. The device is provided with a water supply container, a filtering and drying container, and at least two reaction containers in the shell. The water supply unit supplies water to each reaction container through the pipeline, and the generated hydrogen is output after drying and filtering. The use method emphasizes supplying water to different reaction containers in sequence to realize real-time hydrogen use. This scheme mainly relies on the water supply process of the water supply unit and the organization mode of multiple reaction containers to adjust the reaction. Under the working conditions of short-time fluctuation of water supply amount, residual water in the pipeline or local water accumulation, the hydrogen production output is still easily affected by the change of free water state and fluctuates. At the same time, after stopping water supply, the continuous reaction caused by residual water in the reaction space is still difficult to completely avoid, thereby affecting the controllability and use convenience of shutdown.

[0006] Similarly, in the invention CN114195095A, a high-temperature continuous solid block hydrogenated magnesium hydrogen production control system is disclosed. The system includes a solid hydrogen storage device, a hydrogen release cabin, and a reaction water storage tank. The reaction water enters the hydrogen release cabin through the pipeline with an electric control valve and a water pump, and is matched with a feeding mechanism, a liquid filter device, and a water recovery cycle. It is proposed to adjust the reaction rate by using solid block hydrogenated magnesium with different particle sizes to obtain a more stable hydrogen production process. In order to realize continuous and stable hydrogen supply, this scheme needs more mechanisms and control links to cooperate, and the system composition is relatively complex and strongly dependent on external control units. When the water supply is uneven for a short time, the water is stopped or there is residual water, the disclosed content still mainly relies on device control and process management to avoid the continuation of the reaction after stopping water supply or the fluctuation of the output with the change of the water state, thereby limiting the stable output and controllable shutdown in a simplified application scenario.

[0007] Therefore, how to make the hydrogen production process more stable, the hydrogen output more stable, and the shutdown process more controllable under the working conditions of fluctuation of water supply amount or stopping water supply, while reducing the dependence on valve pump adjustment and complex control links, is a problem to be solved by those skilled in the art. SUMMARY

[0008] In view of the defects in the prior art, the present application provides a hydrogen slow-release composite material based on water self-regulation, which can self-regulate the water entering the reaction environment when the external water supply fluctuates, making the effective water amount participating in the hydrolysis reaction of magnesium hydride more stable, thereby making the hydrogen production process more easily maintain a slow and stable release state, and reducing the dependence on high-precision external water supply equipment and complex control links.

[0009] In a first aspect, the present application provides a hydrogen slow-release composite material based on water self-regulation, which comprises the following raw materials in mass percentage: Hydrogen-producing components, 15–25 wt%, including solid hydrogen-producing materials, used to react with water to release hydrogen; Water-absorbing component, 50–80 wt%, used for water absorption and retention; Water-consuming component, 5–25 wt%, used to react with water to consume water; Wherein, the total solid water content corresponding to the water-absorbing component and the water-consuming component is greater than the theoretical water content required for the complete reaction of the hydrogen-producing component; The raw materials are mixed, compacted, and molded to obtain the hydrogen slow-release composite material.

[0010] In the hydrogen slow-release composite material of this invention, the hydrogen-producing component undergoes a hydrolysis reaction with water to release hydrogen gas. The hydrogen production system is highly sensitive to moisture, especially when using a miniaturized and convenient peristaltic pump for water supply. The water supply is prone to fluctuations, leading to over-reaction of the hydrogen-producing component and affecting the stable supply of hydrogen. Therefore, real-time control and matching of the water volume reacting with the hydrogen-producing component is a crucial aspect of this invention. Specifically, after water is introduced, most of the water is absorbed and fixed by the water-absorbing component, while the hydrogen-producing component reacts with a small portion of the water to generate hydrogen gas, thereby reducing the impact of peristaltic pump water supply fluctuations on hydrogen production. Simultaneously, the water-consuming component reacts with water to consume free water. By limiting the total solid water volume corresponding to the water-absorbing and water-consuming components to be greater than the theoretical water volume required for the complete reaction of the hydrogen-producing component, free water can be continuously fixed or consumed when the water supply stops. This causes a rapid decrease in available water at the hydrogen-producing component interface, thereby inhibiting further reaction and improving the controllability of the shutdown process, reducing the risk of continued reaction due to residual moisture.

[0011] Preferably, the solid hydrogen-producing material includes one or more of Mg powder, magnesium hydride, magnesium-hydrogen complex, calcium hydride, potassium hydride, lithium borohydride, and potassium borohydride. Optionally, the hydrogen-producing component further includes a room-temperature catalyst, including one or more of citric acid, ferric chloride, and aluminum ferric sulfate, wherein the mass ratio of the room-temperature catalyst to the solid hydrogen-producing material is 1:(2-10).

[0012] For magnesium-based hydrogen production systems such as Mg powder, magnesium hydride, and magnesium-hydrogen complexes, room-temperature catalysts can be introduced into the hydrogen-producing components to improve room-temperature start-up and promote a more stable reaction process. These room-temperature catalysts may include one or more of citric acid, ferric chloride, or aluminum ferric sulfate. For solid hydrogen production materials with high water reactivity, such as calcium hydride and potassium hydride, hydrogen production can be achieved by reacting with water at room temperature, typically without the need for additional catalysts. For borohydride systems, the corresponding reaction-promoting systems can be selected based on their hydrolysis characteristics. For example, potassium borohydride can be combined with phosphoric acid or boric acid to promote hydrogen release from hydrolysis, while lithium borohydride can be combined with ferric chloride to promote the reaction. By selecting suitable reaction-promoting systems for different solid hydrogen production materials or simplifying the addition of components in catalyst-free material systems, it is beneficial to achieve a more controllable hydrogen production process and more stable hydrogen release performance under room-temperature conditions.

[0013] Preferably, the absorbent component includes at least one of superabsorbent resin and superabsorbent fiber; Water-consuming components are inorganic solids that react chemically with water to consume free water, including one or more of calcium oxide and magnesium oxide.

[0014] The water-consuming component is an inorganic solid capable of chemically reacting with water to consume free water, and this reaction does not produce gases or toxic byproducts. The water-consuming component includes one or more of calcium oxide and magnesium oxide. After absorbing or binding moisture, the water-consuming component reduces the free water content, thereby reducing the amount of flowable moisture within the material under conditions of water supply interruption or insufficient supply. This reduces the possibility of residual moisture causing the reaction to continue, improving the controllability of the shutdown process and reducing fluctuations in output caused by changes in moisture content.

[0015] Superabsorbent polymer (SAP) is a functional polymer material capable of absorbing hundreds or even thousands of times its own weight in water. The surface of SAP particles typically has hydrophilic groups, such as carboxyl, hydroxyl, and amino groups. Its water absorption behavior is related to the osmotic pressure caused by the internal ion concentration difference and the cross-linking structure. The cross-linking structure can be used to regulate water absorption and retention properties. Due to its strong water absorption capacity and ability to withstand certain pressure without leakage, it is widely used in soil water retention materials, sanitary materials such as sanitary paper and diapers, and in recent years has also been used in waterproofing materials and building materials such as concrete.

[0016] Superabsorbent fiber (SAF) is a special functional fiber developed after superabsorbent polymer (SAP). Its water absorption rate is tens or hundreds of times higher than that of conventional synthetic fibers, exhibiting high water absorption, excellent water retention, and good shape retention. The "superabsorbent fiber" described in this application refers to a fibrous superabsorbent material formed by introducing a superabsorbent polymer phase onto a fiber matrix. The fiber matrix is ​​one or more of cellulose fibers, regenerated cellulose fibers, polyolefin fibers, or polyamide fibers. The superabsorbent polymer phase is fixed inside and outside the fiber matrix by coating, grafting, or co-extrusion integral molding. The superabsorbent polymer phase is obtained by polymerization of acrylic acid and / or acrylates as the main monomers in the presence of a multifunctional crosslinking agent, and its repeating structural unit can be represented as [-CH2-CH(COOR1)-]. n R1 is a hydrogen or alkali metal ion, which makes the resulting fiber have a continuous fiber shape in the longitudinal direction and have a high water absorption ratio and water retention capacity.

[0017] More preferably, the superabsorbent fiber can undergo surface crosslinking treatment. For example, after spraying a surface crosslinking agent onto the surface of the superabsorbent fiber, electron beam irradiation is used to crosslink the surface crosslinking agent with the superabsorbent fiber. The crosslinking agent may include one or more of ethylene glycol diglycidyl ether, aziridine crosslinking agent, amide vinyl crosslinking agent, epichlorohydrin, and glycerol. By increasing the crosslinking density of the fiber surface, excessive gelation of the surface after water absorption can be suppressed, making the fiber surface drier, reducing the tendency of fibers to stick together, and maintaining the fiber's water absorption channels, which is beneficial for maintaining good water absorption performance and morphological stability under water absorption conditions.

[0018] Preferably, the raw materials of the hydrogen slow-release composite material further include a water-conducting component, which is a fibrous material with capillary water-conducting ability, and the mass percentage of the water-conducting component is 1-10 wt%. The water-conducting component can be selected from various sources; any fibrous material with water-conducting properties is acceptable. Preferably, the fibrous material includes at least one of viscose fiber, viscose fabric, viscose nonwoven fabric, lyocell fiber, lyocell fabric, and lyocell nonwoven fabric.

[0019] The water-conducting component forms continuous or semi-continuous fiber pores and capillary channels inside the material, causing water entering the system to migrate under the driving force of fiber surface wetting and capillary wicking. This improves the uniformity of water distribution inside the material, reduces the reaction unevenness and gas production fluctuations caused by short-term accumulation of free water in local areas, and facilitates the transfer of water to the inside of the material along a predetermined path, thus making it easier to maintain a stable output of hydrogen production.

[0020] Preferably, the hydrogen slow-release composite material is molded into a composite having a hydrogen-producing part and a water-consuming part; The hydrogen-producing portion includes a mixture of the hydrogen-producing component, a portion of the water-absorbing component, and a portion of the water-conducting component. The water-consuming portion includes the water-consuming component, the remaining water-absorbing component, and the remaining water-conducting component in a water-consuming mixture; The water absorption rate of the water-absorbing component in the hydrogen production section is less than that of the water-consuming component in the water consumption section. The composite is obtained by compacting and combining the hydrogen-producing mixture and the water-consuming mixture.

[0021] This invention utilizes a composite structure with different compositions and functions to ensure a stable hydrogen supply in the hydrogen-producing section under normal water supply and fluctuating water supply conditions. It also enables the water-consuming section to quickly and fully absorb and consume residual free water within the material when water supply ceases, reducing the impact of free water retention on reaction continuation or slow cessation. Specifically, when water flows into the hydrogen-producing section, most of the water is absorbed and fixed by the water-absorbing component, while the hydrogen-producing component reacts with a small portion of the water to generate hydrogen gas, thus reducing the impact of peristaltic pump water supply fluctuations on hydrogen production. As the water supply increases, the hydrogen-producing component in the hydrogen-producing section is gradually consumed, and the water-absorbing component in this section tends to saturate. After water supply stops, a small amount of water may precipitate from the water-absorbing component (such as SAP) in the hydrogen-producing section at room temperature. If this precipitated water cannot be consumed quickly, it will hinder reaction termination. Therefore, by using a water-conducting component and a water-absorbing component with a higher absorption rate (such as SAF) in the water-consuming section, the precipitated small amount of water is captured and supplied to the water-consuming component for consumption, thereby quickly and completely terminating the reaction.

[0022] Optionally, the water-absorbing components of both the hydrogen-producing and water-consuming parts include superabsorbent resin and superabsorbent fiber, with the mass proportion of superabsorbent fiber in the water-consuming part being higher than that in the hydrogen-producing part.

[0023] Preferably, the water-absorbing component in the hydrogen-producing section is made of superabsorbent resin, and the water-absorbing component in the water-consuming section is made of superabsorbent fiber, with a mass ratio of superabsorbent resin to superabsorbent fiber of (1-5):(2-15). The mass ratio of the water-conducting component in the hydrogen-producing section to the water-consuming section is 1:(1-5).

[0024] Under the aforementioned material distribution relationship, the hydrogen production section can possess a water absorption buffering capacity that matches water supply fluctuations, while the water consumption section has sufficient water absorption and morphology retention capabilities. This avoids situations where insufficient free water control in the hydrogen production section or channel blockage in the water consumption section occurs due to improper distribution of water-absorbing materials. Furthermore, by limiting the mass ratio of the water-conducting component in the hydrogen production section to that in the water consumption section to 1:(1-5), a more matched capillary water conduction and water migration gradient can be formed within the composite. This makes it easier to maintain the migration speed and amount of water between the two parts within an appropriate range, thereby balancing the water supply stability during the hydrogen production stage and the water reduction effect during the water outage stage, resulting in a more stable overall output and easier shutdown control.

[0025] Preferably, in the water-consuming portion of the composite, the water-consuming component accounts for 10–25 wt% of the total mass of the composite material. When a composite structure is used, the hydrogen production and water-consuming portions are set independently, allowing them to function largely without interference. To enhance the water consumption effect and improve the efficiency of water and hydrogen shutdown, the amount of water-consuming component in the water-consuming portion can be relatively high. In contrast, when the hydrogen slow-release composite material is simply mixed and compacted, the water-consuming component is preferably 5–15 wt% of the total mass of the composite material.

[0026] Preferably, a porous silicone layer is pressed between the hydrogen production section and the water consumption section.

[0027] Preferably, the thickness of the porous silicone layer accounts for 1 / 50 to 1 / 10 of the total thickness of the composite structure, more preferably 1 / 30 to 1 / 15.

[0028] The three-dimensional network structure of the porous silica layer (porosity ranging from 30% to 80%, pore size easily tunable in the nanometer to micrometer range) effectively forms a "physical barrier," preventing direct contact or interference between the hydrogen-producing and water-consuming parts. This prevents performance failure caused by mutual influence from physical mixing and chemical reactions, ensuring that both maintain stable physicochemical properties. Furthermore, the porous structure of the silica layer has a dual function of "mass transfer channel" and "rate regulation," making the migration of water from the hydrogen-producing to the water-consuming part smoother and reducing the tendency for localized water accumulation and short-term enrichment caused by free water directly migrating along the interface. The adsorption and retention of water by the porous silica layer can regulate the water state at the interface, reducing instantaneous backflow or reverse permeation of water between the two parts, thus helping to maintain the stability of the hydrogen production process and improve the controllability of the water shutdown phase. In addition, the porous silica layer itself has excellent thermal stability and mechanical properties. When there are temperature and pressure fluctuations in the reaction system, the porous silica layer can provide a buffering and regulating effect for the composite material as a whole, ensuring the safe and stable operation of the system.

[0029] The thickness of the porous silica layer should not be too low, otherwise it will be difficult to play the aforementioned barrier and regulation role; however, its thickness should not be too high either, as it will occupy the space of the effective components of the composite material and reduce the hydrogen supply density.

[0030] Secondly, the present invention also provides a hydrogen slow-release device based on self-regulating moisture, including a reaction container, the reaction container having a water inlet and a gas outlet, and the reaction container being filled with the aforementioned hydrogen slow-release composite material based on self-regulating moisture.

[0031] Preferably, the upper space of the reaction vessel accommodates the hydrogen-producing portion of the hydrogen-releasing composite material, and the lower space accommodates the water-consuming portion of the hydrogen-releasing composite material; the water inlet and the gas outlet are connected to the upper space. The hydrogen-producing component includes the hydrogen-producing component, a portion of the water-absorbing component, and an optional water-conducting component; The water-consuming component includes the water-consuming component, the remaining water-absorbing component, and an optional water-conducting component.

[0032] Thirdly, the present invention also provides a stable hydrogen supply method using the aforementioned hydrogen slow-release device, comprising the following steps: S1. Fill the reaction vessel with a self-regulating hydrogen slow-release composite material based on moisture, so that the water inlet is connected to the water supply unit and the gas outlet is connected to the hydrogen use unit. S2. Water is intermittently or continuously supplied to the reaction vessel through the water inlet. Part of the water is absorbed by the water-absorbing component, and part of the water reacts with the solid hydrogen-producing material in the hydrogen-producing component to generate hydrogen gas, which is then stably output through the gas outlet. The stable hydrogen supply method further includes the following moisture self-regulation stable hydrogen supply step: (1) Increased fluctuations in water supply lead to increased absorption of water-absorbing components, thus maintaining the water consumption of hydrogen-producing components; (2) Stop water supply to produce hydrogen. The water analyzed by the water absorption group is consumed by the water-consuming component, and the hydrolysis reaction of the solid hydrogen production material is terminated. (3) When hydrogen production is needed again, repeat step S2.

[0033] Preferably, after the hydrogen slow-release composite material is compacted and molded, it is vacuum-packed, sealed and stored, and when used, the packaging is torn open and filled into the reaction vessel.

[0034] Optionally, after the hydrogen slow-release composite material is filled, the reaction vessel is closed, a vacuum is drawn into the reaction vessel through the gas outlet, and then the process proceeds to step S2.

[0035] Fourthly, the present invention also provides an application of the aforementioned hydrogen slow-release composite material or the aforementioned hydrogen slow-release device in a hydrogen source system.

[0036] The hydrogen source system includes, but is not limited to, portable hydrogen inhalation devices, hydrogen release glasses, hydrogen water cups, and other medical and health care equipment.

[0037] The present invention provides a hydrogen slow-release composite material, device, and method based on moisture self-regulation, which has at least the following beneficial effects: (1) When there are fluctuations in the external water supply, the hydrogen slow-release composite material of the present invention can spontaneously regulate the water entering the reaction environment, so that the effective water volume participating in the magnesium hydride hydrolysis reaction is more stable, thereby making it easier to maintain a slow and stable hydrogen release state in the hydrogen production process, and the hydrogen output is less likely to fluctuate significantly with the water supply fluctuation, and the dependence on high-precision external water supply equipment and complex control links is reduced.

[0038] (2) Under the condition of water supply stoppage or insufficient water supply, the material system can promote the gradual reduction of free water content, making the hydrolysis reaction easier to terminate in time, reducing the risk of reaction continuation due to residual water, thereby improving the controllability and safety of the shutdown process.

[0039] (3) By coordinating the absorption, retention, migration and consumption of water in the material, the present invention makes it less likely for water to accumulate locally or cause adverse effects due to migration imbalance during the reaction process, thereby improving the uniformity and stability of the reaction process, and making it easier to achieve stable hydrogen release and controllable shutdown in the same material system. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the structure of a hydrogen slow-release composite material based on self-regulating moisture according to an embodiment of the present invention; Figure 2 for Figure 1 A schematic diagram of the compaction molding of hydrogen-released composite materials; Figure 3 This is a schematic diagram of the structure of a hydrogen slow-release composite material based on self-regulating moisture according to another embodiment of the present invention; Figure 4 for Figure 3 A schematic diagram of the compaction molding of hydrogen-released composite materials; Figure 5 This is a schematic diagram of the structure of a hydrogen slow-release device based on self-regulating moisture according to an embodiment of the present invention.

[0041] Explanation of reference numerals in the attached figures: 1-Solid hydrogen production material, 21-Super absorbent resin, 22-Super absorbent fiber, 3-Water-consuming component, 4-Room temperature catalyst, 5-Water-conducting component, 100-Hydrogen production section, 200-Water-consuming section, 300-Porous silica gel layer, 10-Reaction vessel, 11-Gas outlet, 12-Water inlet. Detailed Implementation

[0042] To better understand the above technical solutions, a detailed description of the solutions will be provided below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0043] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0044] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0045] like Figures 1-5 As shown, the present invention provides a hydrogen slow-release composite material based on moisture self-regulation, wherein the hydrogen slow-release composite material comprises the following raw materials by mass percentage: This invention provides a self-regulating hydrogen-releasing composite material, which comprises the following raw materials by weight percentage: (1) A hydrogen-producing component, 15-25 wt%, comprising a solid hydrogen-producing material 1, used to react with water to release hydrogen; the solid hydrogen-producing material 1 comprises one or more of Mg powder, magnesium hydride, magnesium-hydrogen complex, calcium hydride, potassium hydride, lithium borohydride, and potassium borohydride. Optionally, the hydrogen-producing component further comprises a room-temperature catalyst 4, the room-temperature catalyst comprising one or more of citric acid, ferric chloride, and aluminum ferric sulfate, wherein the mass ratio of the room-temperature catalyst to the solid hydrogen-producing material is 1:2 to 10.

[0046] (2) Water-absorbing component, 50-80 wt%, used for water absorption and retention, and capable of releasing some water; the water-absorbing component includes at least one of superabsorbent resin 21 and superabsorbent fiber 22. The superabsorbent resin 21 is a polymeric water-absorbing material, and the surface of the superabsorbent resin particles usually has hydrophilic groups such as carboxyl, hydroxyl, and amino groups. The superabsorbent fiber 22 is a fibrous superabsorbent material. The "superabsorbent fiber" refers to a fibrous superabsorbent material formed by introducing a superabsorbent polymer phase onto a fiber matrix. The fiber matrix is ​​one or more of cellulose fiber, regenerated cellulose fiber, polyolefin fiber, or polyamide fiber. The superabsorbent polymer phase is fixed inside and outside the fiber matrix by coating, grafting, or co-extrusion integral molding. The superabsorbent polymer phase is obtained by polymerization of acrylic acid and / or acrylate as the main monomers in the presence of a multifunctional crosslinking agent. Its repeating structural unit can be represented as [-CH2-CH(COOR1)-]n, where R1 is hydrogen or alkali metal ion. More preferably, the superabsorbent fiber can undergo surface crosslinking treatment, for example, after applying a surface crosslinking agent to the surface of the superabsorbent fiber, the surface crosslinking agent and the superabsorbent fiber are crosslinked by electron beam irradiation; the crosslinking agent includes one or more of ethylene glycol diglycidyl ether, aziridine crosslinking agent, amide vinyl crosslinking agent, epichlorohydrin and glycerol.

[0047] (3) Water-consuming component 3, 5-25 wt%, is used to react with water to consume water; the water-consuming component 3 is an inorganic solid that reacts chemically with water to consume free water, including one or more of calcium oxide and magnesium oxide. In the case of simple mixing and compaction of hydrogen-release composite material, the water-consuming component should preferably account for 5-15 wt% of the total mass of composite material; when the hydrogen-release composite material uses a composite structure, the water-consuming component is set in the water-consuming part, and the amount accounts for 10-25 wt% of the total mass of composite material.

[0048] In one preferred embodiment, the raw materials of the hydrogen slow-release composite material further include a water-conducting component 5, which is a fibrous material with capillary water-conducting capability, and the mass percentage of the water-conducting component 5 is 1-10 wt%. The fibrous material includes at least one of viscose fiber, viscose fabric, viscose nonwoven fabric, lyocell fiber, lyocell fabric, and lyocell nonwoven fabric.

[0049] The hydrogen-producing component, water-absorbing component, water-consuming component 3, and optional water-conducting component 5 can be blended and then compacted to obtain a hydrogen slow-release composite material of the required size.

[0050] In one preferred embodiment, such as Figure 1 and Figure 2The hydrogen-releasing composite material is molded into a composite having a hydrogen-producing portion 100 and a water-consuming portion 200. The hydrogen-producing portion 100 includes a hydrogen-producing mixture comprising the hydrogen-producing component 1, a portion of a water-absorbing component, and a portion of a water-conducting component. The water-consuming portion includes a water-consuming mixture comprising the water-consuming component 3, the remaining water-absorbing component, and the remaining water-conducting component 5. The hydrogen-producing mixture and the water-consuming mixture are compacted and bonded together to obtain the composite. The water absorption rate of the water-absorbing component in the hydrogen-producing portion 100 is less than the water absorption rate of the water-absorbing component in the water-consuming portion 200.

[0051] In one preferred embodiment, the water-absorbing component in the hydrogen-generating section 100 is a superabsorbent resin 21, and the water-absorbing component in the water-consuming section 200 is a superabsorbent fiber 22. The mass ratio of the superabsorbent resin 21 to the superabsorbent fiber 22 is (1-5):(2-15); the mass ratio of the water-conducting component 5 in the hydrogen-generating section 100 to the water-conducting component 5 in the water-consuming section 200 is 1:(1-5).

[0052] In one preferred embodiment, such as Figure 3 and Figure 4 A porous silicone layer 300 is pressed between the hydrogen production section 100 and the water consumption section 200.

[0053] The total solid water content corresponding to the water-absorbing components (21, 22) and the water-consuming component 3 is greater than the theoretical water content required for the complete reaction of the hydrogen-producing components; the raw materials are mixed and compacted to obtain the hydrogen slow-release composite material.

[0054] The preparation method of the above-mentioned hydrogen slow-release composite material based on self-regulation of moisture is as follows: weigh each raw material according to the formula; premix the solid hydrogen production material 1 with the optional room temperature catalyst 4, and then mix it evenly with the water-absorbing component (21,22) and the water-consuming component 3; when the water-conducting component 5 is included, further mix the water-conducting component 5 with the above mixture evenly; then put the mixture into a mold and compact it to obtain an integral compacted body.

[0055] For a composite structure having a hydrogen-producing portion 100 and a water-consuming portion 200, a hydrogen-producing mixture and a water-consuming mixture are prepared separately and pre-compacted separately. Then, the two are stacked and compacted together, as shown below. Figure 2 When the porous silica gel layer 300 is installed, it is placed between the pre-pressed hydrogen-producing part 100 and the water-consuming part 200, and simultaneously pressed and formed during the compaction process. Figure 4 .

[0056] like Figure 5 As shown, the present invention also provides a hydrogen slow-release device based on self-regulating moisture, including a reaction container 10, wherein the reaction container 10 is provided with a water inlet 12 and a gas outlet 11, and the reaction container 10 is filled with the above-mentioned hydrogen slow-release composite material based on self-regulating moisture.

[0057] In a preferred embodiment, the reaction vessel 10 is a sealable container with an upper space and a lower space formed along its height. The upper space is used to accommodate the hydrogen-producing portion 100 of the hydrogen-releasing composite material, and the lower space is used to accommodate the water-consuming portion 200 of the hydrogen-releasing composite material. The water inlet 12 and the gas outlet 11 are both located in the upper region of the reaction vessel and communicate with the upper space, allowing water to enter the upper space and come into contact with the hydrogen-producing portion. The generated hydrogen gas is collected in the upper space and then discharged through the gas outlet.

[0058] The water inlet 12 can be connected to a water supply unit, which can be a combination of a liquid storage container and valves or pumps. The gas outlet 11 can be connected to a hydrogen consumption unit, which can be a hydrogen consumption device or a gas storage buffer assembly. Before the device is put into use, the reaction vessel 10 can be checked for sealing to ensure that the connection between the water inlet 12 and the gas outlet 11 meets the requirements for water and gas supply.

[0059] In another preferred embodiment, the outlet 11 further includes at least a separation layer covering the outlet 11, the separation layer allowing hydrogen to pass through and blocking or absorbing the reaction medium and solid products.

[0060] The hydrogen-producing section 100 includes the hydrogen-producing component, a portion of the water-absorbing component, and an optional water-conducting component. The water-consuming section 200 includes the water-consuming component, the remaining water-absorbing component, and an optional water-conducting component. During filling, the pressed hydrogen-releasing composite material is placed into the reaction vessel 10 with the hydrogen-producing section 100 facing upwards and the water-consuming section 200 facing downwards. The vessel lid is then closed and sealed.

[0061] In another preferred embodiment, multiple water inlets 12 are provided on the container lid, for example, forming an annular closed water inlet band, so that water can enter the reaction vessel 10 more evenly. During the reaction, the pressure inside the reaction vessel 10 increases, and pressurized water can be introduced into the water inlet band.

[0062] In another preferred embodiment, a gap exists between the inner top surface of the reaction vessel 10 and the hydrogen-releasing composite material, and the gap is filled with the water-conducting component 5, so that the incoming water can be supplied to the composite material more uniformly. See [link to previous embodiment]. Figure 5 .

[0063] In another preferred embodiment, the reaction vessel 10 may be provided with structural components for limiting or supporting, so as to keep the relative positions of the hydrogen-producing part and the water-consuming part stable within the vessel. The structural components may be in the form of partitions, support nets or limiting rings, etc. The structural components are provided on the inner wall of the reaction vessel or integrally formed with the reaction vessel, and are used to position the filled composite material and prevent it from shifting significantly during use.

[0064] The present invention also provides a stable hydrogen supply method using the above-mentioned hydrogen slow-release device, comprising the following steps.

[0065] S1. Prepare a hydrogen slow-release composite material based on self-regulating moisture, fill the reaction vessel 10 with the hydrogen slow-release composite material, or fill the reaction vessel with a pre-formed and sealed package of the hydrogen slow-release composite material. When the composite material is a composite structure having a hydrogen-producing part 100 and a water-consuming part 200, the composite is placed in the reaction vessel 10 with the hydrogen-producing part 100 facing upward and the water-consuming part 200 facing downward, so that the hydrogen-producing part 100 is located in the upper space of the reaction vessel and the water-consuming part 200 is located in the lower space of the reaction vessel. Optionally, the water-conducting component 5 is filled in the gap between the top surface of the reaction vessel 10 and the hydrogen slow-release composite material; The container lid is then closed to form a sealed reaction vessel 10, connecting the water inlet 12 to the water supply unit and the gas outlet 11 to the hydrogen utilization unit.

[0066] Optionally, a sealed reaction space can be obtained by evacuating the reaction vessel 10 through the gas outlet 11, which is beneficial to improving the purity of the hydrogen gas discharged after water supply.

[0067] S2. Start the water supply unit and supply water to the reaction vessel 10 intermittently or continuously through the water inlet 12. The water supply method can be set to drip water supply, pulse water supply, or constant flow water supply according to the needs of the hydrogen-using unit. After the water enters the upper space of the reaction vessel 10, it first achieves uniform dispersion of water on the top of the composite material through the water-conducting component 5 in the gap; then, the water comes into contact with the hydrogen-producing part 100 and triggers the hydrolysis reaction of the solid hydrogen-producing material 1. The generated hydrogen gas is collected in the upper space and then filtered through the gas outlet 11 and its separation layer before being output to the hydrogen-using unit.

[0068] In the hydrogen supply process of this invention, to obtain relatively stable hydrogen, it is necessary to control the amount of water reacting with the hydrogen-producing component. After water is introduced, most of the water is absorbed by the water-absorbing component (SAP), while the hydrogen-producing component reacts with a small portion of the water to generate hydrogen. Subsequently, at room temperature, the water-absorbing component (SAP) will precipitate some water, which is captured by the SAF with a higher water absorption rate and combined with the water-consuming material. This allows for flexible control of the amount of water reacting with magnesium hydride, thereby achieving a stable hydrogen supply. Specifically, water supply adjustment and operation switching can be performed as follows: (1) When the water supply fluctuates, the amount of water-absorbing component SAP in the hydrogen production section 100 increases, maintaining the water consumption of the hydrogen production component, so that the reaction vessel 10 can continuously and stably produce hydrogen and output it from the gas outlet 11. (2) When it is necessary to stop the hydrogen supply or suspend the hydrogen production, the water supply is stopped. The water precipitated by the water-absorbing component SAP in the hydrogen production section 100 is quickly captured by the water-absorbing component SAF in the water-consuming section 200 with a larger water absorption rate. The water is quickly introduced from the hydrogen production section 100 to the water-consuming section 200 for consumption by the water-consuming component 3, and the hydrolysis reaction of the solid hydrogen production material 1 is terminated. (3) When hydrogen production is needed again, restart the water supply unit and continue to supply water to the reaction vessel according to step S2, so that the device can resume hydrogen production and output through the gas outlet 11.

[0069] In one specific embodiment, to adapt to different hydrogen demand, the water supply unit can use a water storage container with valves to achieve intermittent water supply, or it can use a pump to achieve continuous water supply; the water supply volume and water supply interval can be set according to the hydrogen consumption level of the hydrogen-using unit. Through the configuration of the hydrogen slow-release composite material and its composite of the present invention, the influence of water volume fluctuations can be avoided during the hydrogen supply process, a relatively stable hydrogen supply can be obtained, ensuring the safety and stability of hydrogen use, and helping to extend the service life of hydrogen-using equipment.

[0070] Example 1 The hydrogen slow-release composite material is composed of the following raw materials by mass percentage: (1) Solid hydrogen production material: magnesium hydride 20wt%; (2) Catalyst at room temperature: 2.5 wt% ferric chloride; (3) Water-absorbing component: Superabsorbent polymer (SAP) 65wt%; (4) Water-consuming components: Calcium oxide 7.5 wt%; (5) Water-conducting component: 5wt% viscose fiber.

[0071] Magnesium hydride and ferric chloride together constitute the hydrogen-producing component. The above raw materials are weighed according to the stated proportions, mixed evenly, and then compacted to obtain the hydrogen-releasing composite material.

[0072] Example 2 The difference between Example 2 and Example 1 is that the absorbent component includes 25wt% superabsorbent polymer (SAP) and 40wt% superabsorbent fiber (SAF).

[0073] Example 3 In this embodiment, the hydrogen slow-release composite material is molded into a composite having a hydrogen-producing portion and a water-consuming portion. The overall material composition of the composite is the same as in Example 2, by mass percentage. The hydrogen-producing portion includes a hydrogen-producing mixture. (1) Solid hydrogen production material: magnesium hydride 20wt%; (2) Catalyst at room temperature: 2.5 wt% ferric chloride; (3) Water-absorbing component: Superabsorbent polymer (SAP) 25wt%; (4) Water-conducting component: 2wt% viscose fiber.

[0074] The water-consuming part includes the water-consuming mixture: (1) Absorbent component: Super absorbent fiber SAF 35wt%; (2) Water-consuming components: calcium oxide 12.5 wt%; (3) Water-conducting component: 3wt% viscose fiber.

[0075] The hydrogen-producing portion is pre-compressed from a hydrogen-producing mixture, and the water-consuming portion is pre-compressed from a water-consuming mixture. The pre-compressed hydrogen-producing portion and the pre-compressed water-consuming portion are stacked and compacted together to obtain the composite.

[0076] Example 4 The hydrogen-releasing composite material and its composite structure in this embodiment are the same as those in Embodiment 3 in terms of the hydrogen-generating and water-consuming portions. The difference is that a porous silica gel layer is provided between the hydrogen-generating and water-consuming portions in the composite structure. The thickness of the porous silica gel layer is 1 / 20 of the total thickness of the composite structure, and the porosity is about 60%.

[0077] The hydrogen-producing part is pre-pressed from a hydrogen-producing mixture, and the water-consuming part is pre-pressed from a water-consuming mixture. The pre-pressed hydrogen-producing part and the pre-pressed water-consuming part are stacked on both sides of a porous silicone layer and then compacted to obtain the composite of this embodiment.

[0078] Example 5 The difference between the hydrogen slow-release composite material in this embodiment and that in Example 4 is that the hydrogen-producing part and the water-consuming part of the composite structure are different.

[0079] The hydrogen production portion, by mass percentage, includes the hydrogen production mixture: (1) Solid hydrogen production material: 15 wt% magnesium hydride; (2) Catalyst at room temperature: 2.5 wt% ferric chloride; (3) Water-absorbing component: Superabsorbent polymer (SAP) 25wt%; (4) Water-conducting component: 2wt% viscose fiber.

[0080] The water-consuming part includes the water-consuming mixture: (1) Absorbent component: Super absorbent fiber SAF 40wt%; (2) Water-consuming components: calcium oxide 12.5 wt%; (3) Water-conducting component: 3wt% viscose fiber.

[0081] Example 6 The difference between the hydrogen slow-release composite material in this embodiment and that in Example 4 is that the hydrogen-producing part and the water-consuming part of the composite structure are different.

[0082] The hydrogen production portion, by mass percentage, includes the hydrogen production mixture: (1) Solid hydrogen production material: 15 wt% magnesium hydride; (2) Catalyst at room temperature: 2.5 wt% ferric chloride; (3) Water-absorbing component: Superabsorbent polymer (SAP) 30wt%; (4) Water-conducting component: 1 wt% viscose fiber.

[0083] The water-consuming part includes the water-consuming mixture: (1) Absorbent component: Super absorbent fiber SAF 45wt%; (2) Water-consuming component: Calcium oxide 5wt%; (3) Water-conducting component: 1.5wt% viscose fiber.

[0084] Tests and Results To evaluate the hydrogen release stability, controllable termination, and sustained release efficiency of the self-regulating hydrogen release composite material based on water supply fluctuations, the following test methods and evaluation indicators were used.

[0085] (1) Test methods and evaluation indicators for hydrogen output stability under fluctuating water supply conditions The hydrogen slow-release composite material samples of Examples 1 to 6 were filled into the reaction vessel, with the water inlet connected to the water supply unit and the gas outlet connected to the gas flow meter.

[0086] The water supply unit is started synchronously to supply water to each reaction vessel. After the hydrogen output enters a relatively stable stage, the water supply conditions are changed according to the preset program to form a water supply fluctuation condition, and the gas flow meter fluctuation of each reaction vessel is recorded. When it is necessary to test the controllability of shutdown, the water supply unit is stopped from supplying water to the reaction vessel, while the hydrogen flow rate is continuously recorded. The termination response time is used as the evaluation index, which is defined as the time required from the moment the water supply is stopped to the moment the hydrogen supply is stopped.

[0087] The results are shown in Table 1: Table 1:

[0088] (2) Test methods and evaluation indicators for hydrogen production per unit mass The hydrogen production per unit mass of solid hydrogen-producing material (1g) was used as the evaluation index. According to calculations, the theoretical water consumption for the complete hydrolysis of 1g of MgH2 is about 1.4ml. 50ml of water was continuously introduced into the samples (5g) of each embodiment using a peristaltic pump, the hydrogen production value of each sample was detected, and the sustained-release efficiency parameters were calculated.

[0089] The hydrogen production value is the ratio of the cumulative hydrogen production volume to the mass of the hydrogen slow-release composite material used. Since the porous silica layer has large pores and a small mass, it is not included in the total mass calculation.

[0090] Hydrogen production (ml / g) = Actual hydrogen production / Mass of hydrogen slow-release composite material; The actual hydrogen production is measured in ml, and the mass of the hydrogen slow-release composite material is measured in g.

[0091] Examples 1-6 all used 1g of MgH2 to prepare hydrogen slow-release composite materials, with a theoretical hydrogen production of approximately 1700ml.

[0092] Calculate the sustained-release efficacy parameter P (in %): P (%) = (Actual hydrogen production A / Theoretical hydrogen production B) × Mass percentage of slow-release components C (%); The results are shown in Table 2: Table 2

[0093] The smaller the value of P, the stronger the hydrogen control capability of the slow-release material under the same packing mass. In practical applications, appropriate slow-release efficiency parameters can be selected based on the amount of hydrogen used and the water supply fluctuations in the application scenario.

[0094] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if these modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include these modifications and modifications.

Claims

1. A hydrogen slow-release composite material based on self-regulating moisture, characterized in that, The hydrogen-release composite material comprises the following raw materials by weight percentage: Hydrogen-producing components, 15–25 wt%, including solid hydrogen-producing materials, used to react with water to release hydrogen; Water-absorbing component, 50-80 wt%, used for water absorption and retention; Water-consuming component, 5–25 wt%, used to react with water to consume water; Wherein, the total solid water content corresponding to the water-absorbing component and the water-consuming component is greater than the theoretical water content required for the complete reaction of the hydrogen-producing component; The raw materials are mixed, compacted, and molded to obtain the hydrogen slow-release composite material.

2. The hydrogen-controlled release composite material as described in claim 1, characterized in that, The solid hydrogen production material includes one or more of the following: Mg powder, magnesium hydride, magnesium-hydrogen complex, calcium hydride, potassium hydride, lithium borohydride, and potassium borohydride. Optionally, the hydrogen-producing component further includes a room-temperature catalyst, including one or more of citric acid, ferric chloride, and aluminum ferric sulfate, wherein the mass ratio of the room-temperature catalyst to the solid hydrogen-producing material is 1:(2-10).

3. The hydrogen-releasing composite material as described in claim 1 or 2, characterized in that, The absorbent component includes at least one of superabsorbent resin and superabsorbent fiber; Water-consuming components are inorganic solids that react chemically with water to consume free water, including one or more of calcium oxide and magnesium oxide.

4. The hydrogen-release composite material as described in claim 3, characterized in that, The raw materials of the hydrogen slow-release composite material also include a water-conducting component, which is a fiber-containing material with capillary water-conducting ability, and the mass percentage of the water-conducting component is 1 to 10 wt%.

5. The hydrogen-release composite material as described in claim 4, characterized in that, The hydrogen slow-release composite material is molded into a composite having a hydrogen-producing part and a water-consuming part; The hydrogen-producing portion includes a mixture of the hydrogen-producing component, a portion of the water-absorbing component, and a portion of the water-conducting component. The water-consuming portion includes the water-consuming component, the remaining water-absorbing component, and the remaining water-conducting component in a water-consuming mixture; The water absorption rate of the water-absorbing component in the hydrogen production section is less than that of the water-consuming component in the water consumption section. The composite is obtained by compacting and combining the hydrogen-producing mixture and the water-consuming mixture.

6. The hydrogen-release composite material as described in claim 5, characterized in that, The water-absorbing component in the hydrogen-generating section uses superabsorbent resin, and the water-absorbing component in the water-consuming section uses superabsorbent fiber. The mass ratio of superabsorbent resin to superabsorbent fiber is (1-5):(2-15). The mass ratio of the water-conducting component in the hydrogen-producing section to the water-consuming section is 1:(1-5).

7. The hydrogen-controlled release composite material as described in claim 5 or 6, characterized in that, A porous silicone layer is pressed between the hydrogen production section and the water consumption section.

8. A hydrogen slow-release device based on self-regulating moisture, characterized in that, The invention includes a reaction vessel, which is provided with a water inlet and a gas outlet, and is filled with a self-regulating hydrogen slow-release composite material based on moisture as described in any one of claims 1 to 7.

9. The hydrogen slow-release device as described in claim 8, characterized in that, The upper space of the reaction vessel accommodates the hydrogen-producing portion of the hydrogen-releasing composite material, and the lower space accommodates the water-consuming portion of the hydrogen-releasing composite material. The water inlet and the gas outlet are connected to the upper space. The hydrogen-producing component includes the hydrogen-producing component, a portion of the water-absorbing component, and an optional water-conducting component; The water-consuming component includes the water-consuming component, the remaining water-absorbing component, and an optional water-conducting component.

10. A method for stable hydrogen supply using the hydrogen slow-release device according to claim 8 or 9, characterized in that, Includes the following steps: S1. Fill the reaction vessel with a self-regulating hydrogen slow-release composite material based on moisture, so that the water inlet is connected to the water supply unit and the gas outlet is connected to the hydrogen use unit. S2. Water is intermittently or continuously supplied to the reaction vessel through the water inlet. Part of the water is absorbed by the water-absorbing component, and part of the water reacts with the solid hydrogen-producing material in the hydrogen-producing component to generate hydrogen gas, which is then stably output through the gas outlet. The stable hydrogen supply method further includes the following moisture self-regulation stable hydrogen supply step: (1) Increased fluctuations in water supply lead to increased absorption of water-absorbing components, thus maintaining the water consumption of hydrogen-producing components; (2) Stop water supply to produce hydrogen. The water analyzed by the water absorption group is consumed by the water-consuming component, and the hydrolysis reaction of the solid hydrogen production material is terminated. (3) When hydrogen production is needed again, repeat step S2.

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