A method of hydrogen energy storage

Abstract

The present disclosure relates to a hydrogen energy storage method, which comprises: contacting raw hydrogen produced by a hydrogen production device, a hydrogenation carrier and a catalyst in a hydrogenation reactor to carry out hydrogen storage treatment, and obtaining a hydrogen storage product; the temperature of the hydrogen storage treatment is 25-90 DEG C; the hydrogenation carrier is selected from one or more of aromatic hydrocarbons; the catalyst is composed of a carrier and an active metal oxide; the carrier comprises a porous body with a pore size of 1-100 nm, and the active metal element in the active metal oxide is Ni. The catalyst of the present disclosure can make the hydrogenation carrier react with the raw hydrogen at a lower temperature, and the hydrogenation carrier can be converted into the hydrogen storage product only by the waste heat of the upstream raw hydrogen, without using an additional heating device, thereby reducing the difficulty of coupling the hydrogen storage treatment and the hydrogen production system, and further reducing the energy consumption of the hydrogen storage treatment.

Description

Technical Field

[0001] This disclosure relates to the field of new energy, and specifically to a method for hydrogen energy storage. Background Technology

[0002] Among numerous chemical hydrogen storage technologies, liquid organic hydrogen carrier hydrogen storage technology is considered the most promising technology for large-scale, spatiotemporal hydrogen storage in the future. It utilizes a reversible addition and dehydrogenation reaction between a liquid organic compound and its corresponding alkane to achieve hydrogen storage and release, offering advantages such as high mass hydrogen storage density and the ability to utilize existing petrochemical facilities for storage and transportation. Hydrogenation is an exothermic reaction, while dehydrogenation is an endothermic reaction, resulting in the loss of 30% of hydrogen during this process. Therefore, reducing energy consumption in the hydrogenation and dehydrogenation stages is a topic worthy of exploration. For this reason, the development of cryogenic hydrogen storage and release technology is crucial. In water electrolysis hydrogen production systems, the electrolyzer temperature is generally around 80-90℃, while the ideal temperature for toluene hydrogen storage is currently 95-105℃. Therefore, simple coupling of green hydrogen production systems and hydrogen storage systems is difficult and requires additional energy. Summary of the Invention

[0003] The purpose of this disclosure is to provide a method for hydrogen energy storage to solve the problem that additional energy is required when hydrogen production and storage systems are coupled in the prior art.

[0004] To achieve the above objectives, this disclosure provides a method for hydrogen energy storage, the method comprising: contacting raw material hydrogen produced by a hydrogen production device, a hydrogenation support, and a catalyst in a hydrogenation reactor to perform hydrogen storage treatment, thereby obtaining a hydrogen storage product; the temperature of the hydrogen storage treatment is 25–90°C; the hydrogenation support is selected from one or more aromatic hydrocarbons; the catalyst comprises a support and an active metal oxide; the support comprises a porous body with a pore size of 1–100 nm, and the active metal element in the active metal oxide is Ni.

[0005] Optionally, the support comprises MCM-41 porous material and / or SBA-15 porous material; the active metal oxide is NiO.

[0006] Optionally, the carrier has a pore size of 1–10 nm and a specific surface area of ​​300–800 m². 2 / g.

[0007] Optionally, based on the total weight of the catalyst, the content of the support is 80-95% by weight; and the content of the active metal oxide is 5-20% by weight.

[0008] Optionally, based on the total weight of the catalyst, the content of the support is 85-93% by weight, and the content of the active metal oxide is 7-15% by weight.

[0009] Optionally, the hydrogenation support is selected from aromatic hydrocarbons with 6 carbon atoms and / or aromatic hydrocarbons with 7 carbon atoms.

[0010] Optionally, the hydrogenation support is benzene and / or toluene.

[0011] Optionally, the conditions for the hydrogen storage treatment include: a temperature of 25–80°C, a pressure of 0.1–0.15 MPa, a time of 2–10 seconds, and a volume hourly space velocity of 0.5–5 h⁻¹. -1 .

[0012] Optionally, the hydrogen content in the raw material hydrogen is 50-100%; the temperature of the raw material hydrogen is 25-90°C.

[0013] Optionally, the hydrogen storage product may be used directly; and / or the hydrogen storage product may be transported to a dehydrogenation unit for dehydrogenation treatment, and the resulting hydrogen may be fed into a downstream hydrogen-using unit.

[0014] Through the above technical solution, the catalyst disclosed herein enables the hydrogenation support to react with the feedstock hydrogen at a lower temperature. The hydrogenation support can be converted into hydrogen storage products using only the residual heat of the upstream feedstock hydrogen, without the need for additional heating devices. This reduces the difficulty of coupling hydrogen storage treatment and hydrogen production systems, and thus reduces the energy consumption of hydrogen storage treatment.

[0015] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of a hydrogen energy storage method disclosed herein.

[0018] Explanation of reference numerals in the attached figures

[0019] 1. Hydrogen production unit; 2. Hydrogenation reactor; 3. Dehydrogenation unit; 4. Downstream hydrogen consumption unit. Detailed Implementation

[0020] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0021] The first aspect of this disclosure provides a method for hydrogen energy storage, the method comprising: contacting raw material hydrogen, a hydrogenation support, and a catalyst generated by a hydrogen production device 1 in a hydrogenation reactor 2 for hydrogen storage treatment to obtain a hydrogen storage product; the temperature of the hydrogen storage treatment is 25-90°C; the hydrogenation support is selected from one or more aromatic hydrocarbons; the catalyst comprises a support and an active metal oxide; the support comprises a porous body with a pore size of 1-100 nm, and the active metal element in the active metal oxide is Ni.

[0022] Through the above technical solution, the catalyst disclosed herein enables the hydrogenation support to react with the feedstock hydrogen at a lower temperature. The hydrogenation support can be converted into hydrogen storage products using only the residual heat of the upstream feedstock hydrogen, without the need for additional heating devices. This reduces the difficulty of coupling hydrogen storage treatment and hydrogen production systems, and thus reduces the energy consumption of hydrogen storage treatment.

[0023] The raw material hydrogen used in this disclosure is produced by hydrogen production device 1, and the hydrogen content in the raw material hydrogen is 30-100% by volume, preferably 50-100% by volume, and more preferably 70-100% by volume. The raw material hydrogen can be selected from one or more of by-product hydrogen, gray hydrogen, blue hydrogen, and green hydrogen. In this embodiment, gray hydrogen refers to hydrogen produced by burning fossil fuels, which emits carbon dioxide and other pollutants during the production process; blue hydrogen refers to hydrogen produced by reforming natural gas through steam methane reforming or autothermal steam reforming coupled with CCUS (carbon dioxide capture and application) technology; green hydrogen refers to hydrogen produced using renewable energy, with no carbon emissions; and by-product hydrogen refers to hydrogen by-products generated in hydrogen production devices and / or hydrogen production devices.

[0024] In this disclosure, the raw material hydrogen is green hydrogen. Electricity generated from renewable energy is directly used in the water electrolysis device, and the hydrogen obtained from electrolysis is used as the raw material hydrogen. The temperature of the raw material hydrogen is 25–90°C, preferably 30–85°C, and more preferably 55–80°C. The hydrogen production device 1 is a conventional choice in the art, and this application does not impose special requirements. For example, the hydrogen production device 1 disclosed herein is a water electrolysis device. The renewable energy includes solar energy and / or wind energy.

[0025] The hydrogenation carrier used in this disclosure is a liquid hydrogen storage material, preferably an aromatic hydrocarbon with 6 carbon atoms and / or an aromatic hydrocarbon with 7 carbon atoms, and more preferably benzene and toluene. In this embodiment, the liquid hydrogen storage material is selected from aromatic hydrocarbon compounds with a high degree of unsaturation. Through hydrogenation treatment, hydrogen can react with the hydrogenation carrier to convert the corresponding aromatic hydrocarbon into the corresponding cycloalkanes, so that hydrogen can be stored in the hydrogenation carrier. The higher the degree of unsaturation of the hydrogenation carrier, the better the hydrogen storage capacity.

[0026] The catalyst used in this disclosure consists of a support and an active metal oxide.

[0027] The carrier comprises MCM-41 porous material and / or SBA-15 porous material; the pore size of the carrier is 1–10 nm, and the specific surface area is 300–800 m². 2 / g.

[0028] SBA-15 porous body refers to SBA-15 mesoporous silica-based molecular sieve, which has highly ordered hexagonal straight pores. The pore size of the straight pores can be flexibly adjusted within the range of 4-10 nm, the pore wall thickness is within the range of 3.1 nm to 6.0 nm, and the specific surface area is 400-800 m². 2 / g, preferably 500-700m 2 / g. The framework structure is stable, with thick walls that are easy to dope.

[0029] MCM-41 is an ordered mesoporous material and a typical representative of the M41S group. At the nanoscale, MCM-41 exhibits an ordered honeycomb-like porous structure, i.e., an array of one-dimensional linear channels arranged in a hexagonal close-packed pattern. The pore size of the MCM-41 porous body can be continuously adjusted within the range of 2-10 nm, preferably 3-5 nm. Electron microscopy observation revealed that the channels can penetrate the entire molecular sieve particle, with pore wall thickness generally around 1 nm; the specific surface area is 350-800 m² / g. 2 / g, preferably 500-700m 2 / g.

[0030] The active metal element in the active metal oxide includes one or more of Ni, Pd, Pt, V, Cr and Co, with Ni being preferred.

[0031] The active metal oxide includes Ni2O3 and / or NiO, preferably NiO.

[0032] In a preferred embodiment, the carrier is an SBA-15 porous body, and the active metal oxide is NiO.

[0033] In one embodiment, based on the total weight of the catalyst, the content of the support is 80-95% by weight; and the content of the active metal oxide is 5-20% by weight.

[0034] In a preferred embodiment, the content of the support is 85-93% by weight and the content of the active metal oxide is 7-15% by weight, based on the total weight of the catalyst.

[0035] In one specific embodiment, the preparation method of NiO-loaded SBA-15 porous body includes: dissolving a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock polymer (abbreviated as P123) in distilled water at room temperature, then adding tetraethyl orthosilicate, stirring until homogeneous, adding hydrochloric acid solution, and then heating to react. After the reaction is complete, filtering, washing with water, drying and calcining the solid product, yielding mesoporous SBA-15 porous body. Alternatively, dissolving an appropriate amount of nickel nitrate in ethanol solvent, adding the SBA-15 porous body, reacting, evaporating the solvent, and calcining, yielding NiO-loaded SBA-15 porous body.

[0036] In the above embodiments, in the presence of hydrogen, the active metal oxide in the catalyst undergoes a reduction reaction with hydrogen to reduce the active metal oxide to an active metal. The active metal can enhance the reactivity of the hydrogenation reaction between the hydrogenation support and the feedstock hydrogen, and reduce the reaction temperature and pressure of the hydrogenation reaction. For example, the hydrogenation temperature of toluene can be reduced from the lowest ideal temperature of 95-105°C recorded in the literature to a preferred 40°C, and the pressure can be reduced to atmospheric pressure.

[0037] In one embodiment, the conditions for the hydrogen storage treatment include: a temperature of 25–90°C, preferably 25–80°C, more preferably 25–50°C; a pressure of 0.1–0.3 MPa, preferably 0.1–0.15 MPa; a time of 2–10 seconds, preferably 5–10 seconds; and a volume hourly space velocity of 0.5–50 h⁻¹. -1 Preferably 1 to 20 hours -1 .

[0038] The hydrogenation reactor 2 used for hydrogen storage treatment is a conventional choice in the art, and this application does not make any special requirements. For example, the hydrogenation reactor 2 used in this disclosure is a microreactor, and the inner diameter of the reaction tube of the microreactor is 0.6 cm.

[0039] The flow rate of the raw hydrogen is 20-50 mL / min.

[0040] The method further includes first adding the catalyst to the hydrogenation reactor 2 and reducing it under the conditions of raw material hydrogen, and then adding the hydrogenation support to the hydrogenation reactor 2 to carry out the hydrogenation reaction to obtain the hydrogen storage product.

[0041] The reduction treatment is carried out at a temperature of 450–550℃ for 4–6 hours to reduce the active metal oxide supported in the catalyst to the corresponding active metal, thereby enhancing the reactivity of the hydrogenation reaction.

[0042] In one specific embodiment, the hydrogen storage treatment includes: placing a catalyst in a microreactor, performing a reduction treatment for 4–6 hours under feed hydrogen and 450–550°C conditions, and then cooling to room temperature. Under feed hydrogen conditions, a hydrogenation support is added to carry out a hydrogenation reaction to obtain the hydrogen storage product.

[0043] In one embodiment, the hydrogen storage product can be used directly. Specifically, the hydrogen storage product can be used as fuel to supply fuel-using equipment such as automobiles, ships, and aircraft; or it can be used as a solvent or a conventional chemical.

[0044] In another embodiment, the hydrogen storage product is sent to the dehydrogenation unit 3 of the downstream hydrogen-using unit 4 for dehydrogenation treatment to obtain hydrogen and hydrogenation carrier; the obtained hydrogen is sent to the downstream hydrogen-using unit 4 for use, and the obtained hydrogenation carrier is sent out or recycled to the hydrogenation reactor 2 or used directly.

[0045] The dehydrogenation device 3 used in this disclosure is a conventional choice in the art, and this application does not make any special requirements for it. The dehydrogenation method used in this disclosure is a conventional choice in the art, and this application does not make any special requirements for it.

[0046] In one embodiment, a method for hydrogen energy storage includes:

[0047] Catalyst preparation: P123 was dissolved in distilled water at room temperature, followed by the addition of tetraethyl orthosilicate, and the mixture was stirred until homogeneous. Hydrochloric acid solution was then added, and the mixture was heated to react. After the reaction was complete, the mixture was filtered, washed with water, and the solid product was dried and calcined to obtain mesoporous SBA-15 porous material. An appropriate amount of nickel nitrate was dissolved in ethanol solvent, and the SBA-15 porous material was added. After the reaction, the solvent was evaporated, and the mixture was calcined to obtain the catalyst.

[0048] Hydrogen storage treatment: The feedstock hydrogen, hydrogenation support, and catalyst produced by hydrogen production unit 1 are contacted in hydrogenation reactor 2 for hydrogen storage treatment to obtain hydrogen storage products; the conditions for the hydrogen storage treatment include: temperature of 25-90℃, pressure of 0.1-0.15MPa, time of 2-10 seconds, and volume hourly space velocity of 0.5-5h. -1 The hydrogenation carrier is selected from one or more aromatic hydrocarbons; the hydrogen storage product is used directly as fuel; and / or the hydrogen storage product is transported to the dehydrogenation unit 3 for dehydrogenation treatment, and the resulting hydrogen is fed into the downstream hydrogen use unit 4.

[0049] The method provided by the present invention will be further described below through specific embodiments, but this does not limit the present invention.

[0050] Preparation Example 1

[0051] Preparation of catalyst A1: 4 g of P123 was dissolved in 105 g of distilled water at room temperature, followed by the addition of 8.52 g of tetraethyl orthosilicate. The mixture was stirred for 30 minutes, and then 28.6 g of hydrochloric acid solution was added. The mixture was immediately placed in a 60°C oil bath and heated with stirring for 24 hours. After the reaction was complete, the mixture was filtered, washed with water, and the solid product was dried overnight at 80°C and calcined at 550°C for 10 hours to obtain a pore size of 6.8 nm and a specific surface area of ​​650 m². 2 / g of mesoporous SBA-15 support. An appropriate amount of nickel nitrate was placed in 10g of ethanol solvent, dissolved by ultrasonic vibration, and then 3g of mesoporous support was added. After vibrating for another half hour, the ethanol was allowed to evaporate naturally in a fume hood, and then calcined at 500 degrees Celsius for 10 hours to obtain NiO-supported catalyst A1. Based on the total weight of catalyst A1, the content of SBA-15 support was 85% by weight, and the content of NiO was 15% by weight.

[0052] Preparation Example 2

[0053] The method for preparing catalyst A2 is the same as in Example 1, except that the pore size of the SBA-15 porous body in catalyst A2 is 15 nm and the specific surface area is 900 m². 2 / g.

[0054] Preparation Example 3

[0055] The method for preparing catalyst A3 is the same as in Example 1, except that, based on the total weight of catalyst A3, the content of SBA-15 porous body is 95% by weight and the content of NiO is 5% by weight.

[0056] Preparation of Comparative Example 1

[0057] Preparation of comparative catalyst D1: As the main supported metal liquid, 1.328 g of chloroplatinic acid hexahydrate was dissolved in 200 mL of distilled water; as the secondary supported metal liquid, 0.128 g of rhodium chloride trihydrate was dissolved in 100 mL of distilled water; the two aqueous solutions were mixed to prepare a mixture of about 300 mL.

[0058] 4.45 g of activated carbon was impregnated in the mixture as a carrier and stirred thoroughly. After standing overnight, the activated carbon was removed from the mixture, washed thoroughly with water, and dried. Then, the dried activated carbon was impregnated in 500 mL of a 10% sodium borohydride aqueous solution to reduce and activate the supported metal. Further washing and drying were performed to prepare approximately 5 g of comparative catalyst D1. The contents of the main supported metal platinum and the secondary supported metal rhodium in the prepared comparative catalyst D1 were 10 wt% and 1 wt%, respectively. It should be noted that the atomic ratio of platinum to rhodium in this case was rhodium / platinum = 0.053.

[0059] Preparation of Comparative Example 2

[0060] The method for preparing catalyst D2 is the same as in Example 1, except that iron oxide is used instead of nickel oxide as the active metal oxide of the catalyst.

[0061] Preparation of Comparative Example 3

[0062] The method for preparing catalyst D3 is the same as in Example 1, except that non-porous silica (Kyoto Chemical) is used instead of SBA-15 as the support, and comparative catalyst D3 is obtained using the method of preparation in Example 1.

[0063] Example 1

[0064] Hydrogen storage treatment: Catalyst A1 (catalyst bed height 2 cm) was placed in a microreactor (reaction tube inner diameter 0.3 cm), and reduced at 500 °C for 5 h with a hydrogen flow rate of 34 mL / min, followed by cooling to 20 °C. Hydrogen storage treatment was then performed by injecting 0.2 μmL of benzene using a syringe under a hydrogen flow rate of 34 mL / min to obtain cyclohexane. The conditions for the hydrogen storage treatment included: temperature 25 °C, pressure 0.1013 MPa, time 2 seconds, and volume hourly space velocity (VHSV) 0.67 h⁻¹. -1 The hydrogenation support is selected from one or more aromatic hydrocarbons.

[0065] The hydrogen storage product is used directly as fuel; and / or the hydrogen storage product is transported to the dehydrogenation unit 3 for dehydrogenation treatment, and the resulting hydrogen is fed into the downstream hydrogen-using unit 4.

[0066] Example 2

[0067] The method for hydrogen energy storage is the same as in Example 1, except that the hydrogenation carrier is 0.2 μmL of toluene, and the hydrogen storage conditions include: a temperature of 40°C, a pressure of 0.1013 MPa, a time of 2 seconds, and a volume hourly space velocity of 0.67 h⁻¹. -1 .

[0068] Example 3

[0069] The method for hydrogen energy storage is the same as in Example 2, except that the catalyst used is catalyst A2.

[0070] Example 4

[0071] The method for hydrogen energy storage is the same as in Example 2, except that the catalyst used is catalyst A3.

[0072] Comparative Example 1

[0073] The method for hydrogen energy storage is the same as in Example 1, except that catalyst D1 is used.

[0074] Comparative Example 2

[0075] The method for hydrogen energy storage is the same as in Example 2, except that catalyst D1 is used.

[0076] Comparative Example 3

[0077] The method for hydrogen energy storage is the same as in Example 2, except that catalyst D2 is used.

[0078] Comparative Example 4

[0079] The method for hydrogen energy storage is the same as in Example 2, except that catalyst D3 is used.

[0080] Table 1. Conditions and Product Properties of Hydrogen Storage Treatment

[0081]

[0082]

[0083] As shown in Table 1, a comparison of the data from Examples 1-2 and Comparative Examples 1-4 reveals that the catalyst disclosed herein enables the hydrogenation reaction of benzene and toluene at relatively low reaction temperatures and atmospheric pressures. A comparison of the data from Examples 2, 3, and 4 shows that the parameters of the support in the catalyst satisfy a pore size of 1-10 nm and a specific surface area of ​​300-800 m². 2 When the content of the catalyst is 85-93% by weight and the content of the support is 7-15% by weight, based on the total weight of the catalyst, the conversion rate of the hydrogenation support can be improved, thereby enhancing the hydrogen storage effect. Furthermore, the hydrogen production device and the hydrogenation device of this disclosure have good temperature matching, eliminating the need for reheating during the hydrogenation reaction. This not only reduces the difficulty of coupling the hydrogen storage device and the hydrogen production device but also reduces the energy consumption of hydrogen storage processing.

[0084] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0085] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0086] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A method for hydrogen energy storage, characterized in that, The method includes: The hydrogen produced by the hydrogen production unit, the hydrogenation support, and the catalyst are contacted in a hydrogenation reactor to perform hydrogen storage treatment, yielding a hydrogen storage product. The conditions for this hydrogen storage treatment include: a temperature of 25–80°C, a pressure of 0.1–0.15 MPa, a time of 2–10 seconds, and a volume hourly space velocity (VHSV) of 0.5–5 h⁻¹. -1 ; The hydrogenation support is benzene and / or toluene; the conversion rate of the hydrogenation support is 100%. The catalyst comprises a support and an active metal oxide; the support comprises an SBA-15 porous body with a pore size of 1-10 nm, and the active metal oxide is NiO; the specific surface area of ​​the support is 300-800 m². 2 / g; Based on the total weight of the catalyst, the content of the support is 85-93% by weight, and the content of the active metal oxide is 7-15% by weight.

2. The method according to claim 1, characterized in that, The hydrogen content in the raw material hydrogen is 50-100% by volume; the temperature of the raw material hydrogen is 25-90℃.

3. The method according to claim 1, characterized in that, The hydrogen storage product can be used directly; and / or, The hydrogen storage product is transported to a dehydrogenation unit for dehydrogenation treatment, and the resulting hydrogen is then fed into downstream hydrogen-using units.

Images