Hydrogen storage hollow glass microsphere and preparation method and hydrogen charging and discharging method thereof

Abstract

The invention discloses a hydrogen storage hollow glass microsphere, a preparation method thereof and a hydrogen charging and discharging method. The hydrogen storage hollow glass microspheres are composed of borosilicate glass ball walls and hollow cavities wrapped by the ball walls, transition metal nanoparticles are dispersed in the borosilicate glass ball walls, and the transition metal nanoparticles are products obtained by reducing transition metal oxide nanoparticles through hydrogen. The preparation method comprises the steps of preparation of uniform glass frits, preparation of primary hollow glass microspheres, preparation of hydrogen storage hollow glass microspheres and the like. The hydrogen charging and discharging method comprises the two steps of hydrogen charging of the hydrogen storage hollow glass microspheres and hydrogen discharging of the hydrogen storage hollow glass microspheres. Under the catalytic action of the transition metal nanoparticles, the hydrogen adsorption free energy is reduced, the permeation and diffusion rate of hydrogen is increased, the hydrogen permeation coefficient of the hydrogen storage hollow glass microspheres at the low temperature of 100-200 DEG C is increased, the operation temperature of hydrogen charging and discharging is reduced, and the energy consumption is reduced.

Description

Technical Field

[0001] This invention relates to the field of hydrogen storage technology, and more specifically, to a hydrogen storage hollow glass microsphere, its preparation method, and its hydrogen filling and releasing method. Background Technology

[0002] Hollow glass microspheres possess advantages such as safety, lightweight, low density, non-toxicity, and low cost, making them suitable as high-pressure containers for hydrogen storage. Hydrogen filling and discharging are primarily achieved through hydrogen permeation through the glass walls of the microspheres, significantly reducing reliance on expensive hydrogen storage pressure vessels. At low temperatures or room temperature, hollow glass microspheres exhibit extremely low hydrogen permeability. When the temperature rises to 300–400°C, hydrogen permeability increases significantly, allowing hydrogen to enter the microsphere cavity under a certain filling pressure (10–200 MPa). When the temperature drops to room temperature, the permeability of the glass walls decreases significantly, storing hydrogen within the microsphere cavity. Raising the temperature again releases the hydrogen. However, due to the low thermal conductivity of the glass components, a high external heating temperature is required for rapid hydrogen filling and discharging. High temperatures not only easily lead to excessive internal pressure within the hollow microspheres, causing damage to the outer walls during filling, but also restrict the permeation and diffusion of hydrogen from the outside into the microspheres, limiting the hydrogen storage capacity of the hollow glass microspheres. Furthermore, the high energy consumption required to maintain the high temperature, as well as the high-temperature system itself, limits its integration into fuel cell systems. Therefore, further reducing the operating temperature required for hollow glass microspheres during hydrogen charging and discharging is a key issue that urgently needs to be addressed for their widespread application in the field of high-efficiency hydrogen storage technology.

[0003] Patent CN201610184565.9 discloses a cobalt-doped glass microsphere, its preparation method, and its applications. The cobalt-doped glass microspheres of this invention can absorb visible light and, upon illumination at room temperature, form rapid channels for gas molecules, thereby achieving controlled release of hydrogen from within the microspheres. However, it does not address the issue of excessively high operating temperatures for hydrogen filling and discharging in hollow glass microspheres. Summary of the Invention

[0004] To address the problem of excessively high operating temperatures for hydrogen filling and discharging in existing hollow glass microspheres, this invention provides a hydrogen storage hollow glass microsphere, its preparation method, and its hydrogen filling and discharging method.

[0005] The hydrogen storage hollow glass microspheres provided by the present invention are composed of a borosilicate glass sphere wall and a hollow cavity enclosed by the sphere wall. Transition metal nanoparticles are dispersed in the borosilicate glass sphere wall. The transition metal nanoparticles are the product of the reduction of transition metal oxide nanoparticles by hydrogen.

[0006] The particle size of the hydrogen storage hollow glass microspheres is generally 10–250 μm, and the wall thickness is generally 0.5–2 μm.

[0007] This invention also provides a method for preparing hydrogen storage hollow glass microspheres, comprising the following steps:

[0008] 1) Preparation of homogeneous glass frit

[0009] Transition metal oxide nanoparticles and glass components are mixed in a certain proportion and melted in a crucible at 1200-1400℃ for 2-4 hours. The molten block is then subjected to rapid cooling, mechanical crushing, mixing and remelting processes until a transparent and uniform glass molten block is obtained.

[0010] The weight of the transition metal oxide nanoparticles is 2 to 15 wt% of the weight of the glass component;

[0011] The transition metal oxide nanoparticles are one or more of the following: single metal oxides, bimetallic oxides, and polymetallic oxides of nickel (Ni), iron (Fe), cobalt (Co), or copper (Cu).

[0012] The glass component comprises, by weight percentage, 62-80 wt% silica, 10-20 wt% boron oxide, 5-10 wt% alumina (Al2O3), and 1-10 wt% foaming agent.

[0013] The silica component is one or both of quartz sand and silica; the boron oxide component is one or more of B2O3, anhydrous borax (Na2O·2B2O3), and boric acid (H3BO3); the foaming agent is one or more of sodium phosphate, sodium sulfate, and sodium nitrate.

[0014] 2) Preparation of primary hollow glass microspheres

[0015] The uniform glass frit prepared in step 1) is mechanically crushed and sieved in sequence. Powder particles with a particle size of 10-80 μm are collected and fed into a flame burner. Under the heating of the combustion flame of the combustion gas and the combustion-supporting gas, they expand to form primary hollow glass microspheres.

[0016] 3) Preparation of hydrogen storage hollow glass microspheres

[0017] The primary hollow glass microspheres prepared in step 2) are heated in a hydrogen atmosphere at 400-600℃ for 6-12 hours to reduce the transition metal oxides and obtain hydrogen storage hollow glass microspheres containing transition metal nanoparticles.

[0018] 4) Sieving of hydrogen storage hollow glass microspheres

[0019] The hydrogen storage hollow glass microspheres prepared in step 3) are sequentially subjected to air cooling, flotation collection, and vacuum drying, and finally sieved to obtain hydrogen storage hollow glass microspheres with different particle size ranges; generally, hydrogen storage hollow glass microspheres with a particle size range of 20 to 200 μm are preferred as the final product.

[0020] The transition metal oxide nanoparticles in step 1) can be prepared by sol-gel method, hydrothermal method or thermal pyrolysis method, and the particle size is 5-50 nm.

[0021] The single metal oxides mentioned are NiO, CoO, and Fe. x O y One or more of the following.

[0022] The bimetallic oxide is one or more of NiFeO, NiCoO, NiCuO, and CoFeO.

[0023] The polymetallic oxide is one or both of FeCoNiO and FeCoNiCuO.

[0024] The combustion gas in step 2) is mainly one of methane, propane and acetylene; the combustion-supporting gas is mainly one of air and oxygen.

[0025] This invention also provides a method for filling and releasing hydrogen into hydrogen-storing hollow glass microspheres, comprising the following steps:

[0026] 1) Hydrogen filling of hydrogen storage hollow glass microspheres

[0027] First, vacuum degassing is performed on the hydrogen storage container after adding hydrogen storage hollow glass microspheres. Then, high-temperature compressed hydrogen is introduced into the hydrogen storage container, with the hydrogen temperature controlled at 100-200℃. The pressure inside the hydrogen storage container is adjusted to 10-100MPa. After the hydrogen storage hollow glass microspheres are saturated with hydrogen, the hydrogen storage container is cooled to below 100℃, preferably to room temperature, to complete the hydrogen filling process.

[0028] 2) Hydrogen release from hydrogen storage hollow glass microspheres

[0029] When releasing hydrogen, the hydrogen storage container is first evacuated to a negative pressure, and then the temperature is gradually increased to 100-200°C, so that the hydrogen-saturated hollow glass microspheres can release hydrogen.

[0030] The present invention has the following beneficial effects:

[0031] 1) Because transition metal nanoparticles are dispersed in the borosilicate glass spheres, the high thermal conductivity of the nanoparticles during the heating and hydrogen charging / discharging process significantly increases the heating rate of the hydrogen storage hollow glass microspheres, thereby improving the hydrogen charging / discharging rate.

[0032] 2) Transition metal nanoparticles can act as catalysts at high temperatures, reducing the hydrogen adsorption free energy, effectively adsorbing and dissociating hydrogen molecules, accelerating the hydrogen permeation and diffusion rate, improving the hydrogen permeability coefficient of hydrogen storage hollow glass microspheres at lower temperatures of 100-200℃, reducing the operating temperature for charging and discharging hydrogen, and reducing energy consumption. Attached Figure Description

[0033] Figure 1 An optical photograph of the hydrogen storage hollow glass microspheres of the present invention;

[0034] Figure 2 This is a comparison chart showing the hydrogen release rates of the hydrogen storage hollow glass microspheres of the present invention and hollow glass microspheres without catalysts. Detailed Implementation

[0035] To more clearly illustrate the present invention, the following description, in conjunction with preferred examples of the preparation of hydrogen storage hollow glass microspheres and embodiments of hydrogen filling and discharging, along with accompanying drawings, further explains the invention. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention.

[0036] Preparation Example 1

[0037] 1) Preparation of homogeneous glass frit

[0038] 20nm nickel oxide (NiO) nanoparticles and glass components are mixed in a certain proportion and melted in a crucible at 1200℃ for 4 hours. The molten block is then subjected to rapid cooling, mechanical crushing, mixing and remelting processes until a transparent and uniform glass molten block is obtained.

[0039] The weight of the nickel oxide (NiO) nanoparticles is 10 wt% of the weight of the glass component.

[0040] The glass components and their contents by weight percentage are: 75 wt% quartz sand, 12 wt% anhydrous borax (Na2O·2B2O3), 5 wt% alumina (Al2O3), and 8 wt% foaming agent sodium phosphate.

[0041] 2) Preparation of primary hollow glass microspheres

[0042] The uniform glass frit from step 1) is mechanically crushed and sieved in sequence. Powder particles with a particle size of 10-80 μm are collected and fed into a flame burner. Under the heating of the combustion flame of the combustion gas and the combustion-supporting gas, they expand to form primary hollow glass microspheres.

[0043] 3) Preparation of hydrogen storage hollow glass microspheres

[0044] The primary hollow glass microspheres from step 2) were heated at 600°C for 6 hours in a hydrogen atmosphere to reduce the transition metal oxides and obtain hydrogen storage hollow glass microspheres containing transition metal nanoparticles.

[0045] 4) Sieving of hydrogen storage hollow glass microspheres

[0046] The hydrogen storage hollow glass microspheres prepared in step 3) were sequentially subjected to air cooling, flotation collection, vacuum drying, and finally sieved to obtain hydrogen storage hollow glass microspheres with a particle size range of 20–200 μm.

[0047] Preparation Example 1 corresponds to Hydrogen Charging and Discharging Example 1

[0048] Hydrogen storage hollow glass microspheres with a particle size range of 20–200 μm were added to a high-pressure vessel for vacuum degassing. Subsequently, hydrogen was added under heating at a pressure of 70 MPa and a heating temperature of 200 °C. Hydrogen release also occurred under heating at 200 °C. The hydrogen storage capacity of the microspheres reached 7 wt%.

[0049] Preparation Example 2

[0050] 1) Preparation of homogeneous glass frit

[0051] After mixing 50nm nickel-iron oxide (NiFeO) nanoparticles and glass components in a certain proportion, the mixture was melted and mixed in a crucible at 1400℃ for 2 hours. The molten block was then subjected to rapid cooling, mechanical crushing, mixing and remelting processes until a transparent and uniform glass molten block was obtained.

[0052] The weight of the nickel-iron oxide (NiFeO) nanoparticles is 8 wt% of the weight of the glass component.

[0053] The glass components and their contents by weight percentage are: 68 wt% silica, 15 wt% boric acid (H3BO3), 7 wt% alumina (Al2O3), and 10 wt% foaming agent sodium sulfate.

[0054] 2) Preparation of primary hollow glass microspheres

[0055] The uniform glass frit from step 1) is mechanically crushed and sieved in sequence. Powder particles with a particle size of 10-80 μm are collected and fed into a flame burner. Under the heating of the combustion flame of the combustion gas and the combustion-supporting gas, they expand to form primary hollow glass microspheres.

[0056] 3) Preparation of hydrogen storage hollow glass microspheres

[0057] The primary hollow glass microspheres from step 2) are heated at 500°C for 6 hours in a hydrogen atmosphere to reduce the transition metal oxides and obtain hydrogen storage hollow glass microspheres containing transition metal nanoparticles.

[0058] 4) Sieving of hydrogen storage hollow glass microspheres

[0059] The hydrogen storage hollow glass microspheres prepared in step 3) were sequentially subjected to air cooling, flotation collection, vacuum drying, and finally sieved to obtain hydrogen storage hollow glass microspheres with a particle size range of 20–200 μm.

[0060] Preparation Example 2 corresponds to Hydrogen charging and discharging Example 2

[0061] Hydrogen storage hollow glass microspheres with a particle size range of 20–200 μm were added to a high-pressure vessel for vacuum degassing. Subsequently, hydrogen was added under heating at a pressure of 10 MPa and a heating temperature of 120 °C. Hydrogen release also occurred under heating at 120 °C. The hydrogen storage capacity of the microspheres reached 1 wt%.

[0062] Preparation Example 3

[0063] 1) Preparation of homogeneous glass frit

[0064] After mixing 25nm iron cobalt nickel copper (FeCoNiCuO) nanoparticles and glass components in a certain proportion, the mixture was melted and mixed in a crucible at 1300℃ for 3 hours. The molten block was then subjected to rapid cooling, mechanical crushing, mixing and remelting processes until a transparent and uniform glass molten block was obtained.

[0065] The weight of the iron cobalt nickel copper (FeCoNiCuO) nanoparticles is 15 wt% of the weight of the glass component.

[0066] The glass components and their contents by weight percentage are: 75 wt% quartz sand, 12 wt% boron oxide (B2O3), 5 wt% alumina (Al2O3) and 8 wt% foaming agent sodium nitrate.

[0067] 2) Preparation of primary hollow glass microspheres

[0068] The uniform glass frit from step 1) is mechanically crushed and sieved in sequence. Powder particles with a particle size of 10-80 μm are collected and fed into a flame burner. Under the heating of the combustion flame of the combustion gas and the combustion-supporting gas, they expand to form primary hollow glass microspheres.

[0069] 3) Preparation of hydrogen storage hollow glass microspheres

[0070] The primary hollow glass microspheres from step 2) are heated at 400°C for 10 hours in a hydrogen atmosphere to reduce the transition metal oxides and obtain hydrogen storage hollow glass microspheres containing transition metal nanoparticles.

[0071] 4) Sieving of hydrogen storage hollow glass microspheres

[0072] The hydrogen storage hollow glass microspheres prepared in step 3) were sequentially subjected to air cooling, flotation collection, vacuum drying, and finally sieved to obtain hydrogen storage hollow glass microspheres with a particle size range of 20–200 μm.

[0073] Preparation Example 3 corresponds to Hydrogen Charging and Discharging Example 3

[0074] Hydrogen storage hollow glass microspheres with a particle size range of 20–200 μm were added to a high-pressure vessel for vacuum degassing. Subsequently, hydrogen was added under heating at a pressure of 40 MPa and a heating temperature of 100 °C. Hydrogen release also occurred under heating at 100 °C. The hydrogen storage capacity of the microspheres reached 4 wt%.

[0075] Figure 1 An optical photograph of the hydrogen storage hollow glass microspheres prepared by the method of the present invention is shown, revealing the microstructure of the hydrogen storage hollow glass microspheres.

[0076] Figure 2 This graph compares the hydrogen release rates of the hydrogen storage hollow glass microspheres of the present invention with those of hollow glass microspheres without a catalyst. The red dots in the graph represent the hydrogen storage hollow glass microspheres containing transition metal nanoparticles of the present invention. Due to the catalytic effect of the transition metal nanoparticles, the hydrogen storage hollow glass microspheres of the present invention can achieve a very high hydrogen release rate at a relatively low temperature of 100℃ to 200℃. In contrast, the hydrogen release rate of the hollow glass microspheres without a catalyst (represented by black squares in the graph) is far lower than that of the present invention, even at high temperatures of 250℃ to 400℃. Therefore, the hydrogen storage hollow glass microspheres of the present invention have significant technical advantages.

Claims

1. A hydrogen storage hollow glass microsphere, characterized by: The hydrogen storage hollow glass microspheres are composed of borosilicate glass walls and hollow cavities enclosed by the walls, and transition metal nanoparticles are dispersed in the borosilicate glass walls, wherein the transition metal nanoparticles are products of reduction of transition metal oxide nanoparticles by hydrogen.

2. The hydrogen storage hollow glass microspheres according to claim 1, characterized in that: The hydrogen storage hollow glass microspheres have a particle size of 10-250 μm and a wall thickness of 0.5-2 μm.

3. A method of producing the hydrogen storage hollow glass microspheres of claim 1, characterized by The method comprises the following steps: 1) Preparation of homogeneous glass frit The transition metal oxide nanoparticles and the glass components are mixed in a certain proportion, and then melted and mixed in a crucible at 1200-1400 ℃ for 2-4 hours. The frit is then subjected to rapid cooling, mechanical crushing, mixing and remelting until a transparent homogeneous glass frit is obtained. The weight of the transition metal oxide nanoparticles is 2-15 wt% of the weight of the glass components. The transition metal oxide nanoparticles are one or more of single metal oxides, double metal oxides and multi-metal oxides of nickel, iron, cobalt or copper. The components and contents of the glass components are as follows in terms of weight percentage: 62-80 wt% of silica component, 10-20 wt% of boron oxide component, 5-10 wt% of aluminum oxide (Al2O3) and 1-10 wt% of foaming agent. The silica component is one or both of quartz sand and silicon dioxide; the boron oxide component is one or more of B2O3, anhydrous borax and boric acid; and the foaming agent is one or more of sodium phosphate, sodium sulfate and sodium nitrate. 2) Preparation of primary hollow glass microspheres The homogeneous glass frit prepared in step 1) is subjected to mechanical crushing and sieving in sequence, and the powder particles with a particle size of 10-80 μm are collected and fed into a flame burner to expand and form primary hollow glass microspheres under the heating of a combustion flame of combustion gas and combustion-supporting gas. 3) Preparation of hydrogen storage hollow glass microspheres The primary hollow glass microspheres prepared in step 2) are heated in a hydrogen atmosphere at 400-600 ℃ for 6-12 hours to reduce the transition metal oxides and obtain hydrogen storage hollow glass microspheres containing transition metal nanoparticles.

4. The method of claim 3, wherein: The hydrogen storage hollow glass microspheres prepared in step 3) are subjected to gas cooling, floatation collection, vacuum drying and sieving in sequence to obtain hydrogen storage hollow glass microspheres with different particle size ranges.

5. The method of claim 3, wherein: The particle size of the transition metal oxide nanoparticles in step 1) is 5-50 nm.

6. The method of claim 3, wherein: The monometallic oxide is NiO, CoO and Fe x O y one or more of the group consisting of 7. The method of claim 3, wherein: The double metal oxides are one or more of NiFeO, NiCoO, NiCuO and CoFeO.

8. The method of claim 3, wherein: The multi-metal oxides are one or both of FeCoNiO and FeCoNiCuO.

9. The method of claim 3, wherein: The combustion gas in step 2) is one of methane, propane and acetylene; and the combustion-supporting gas is one of air and oxygen.

10. A method for charging and discharging hydrogen to the hydrogen storage hollow glass microspheres of claim 1, characterized by 1) Hydrogen charging of hydrogen storage hollow glass microspheres ​ The hydrogen storage hollow glass microspheres are added into a hydrogen storage container, vacuum degassing is carried out, high-temperature compressed hydrogen is introduced into the hydrogen storage container, the hydrogen temperature is controlled at 100-200℃, the pressure in the hydrogen storage container is adjusted to 10-100MPa, the hydrogen storage hollow glass microspheres are saturated with hydrogen, the hydrogen storage container is lowered to below 100℃, preferably to room temperature, and the hydrogen filling process is completed; 2) Hydrogen release of the hydrogen storage hollow glass microspheres During hydrogen release, the hydrogen storage container is first pumped to negative pressure, then gradually heated to 100-200℃, and the hydrogen saturated hydrogen storage hollow glass microspheres release hydrogen.

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