Antioxidant waste magnesium alloy-aqueous solution hydrogen production system and preparation method thereof
By preparing CeNb2O7 bimetallic oxide via a high-temperature solid-state method and treating magnesium-based materials with EDTA-2Na and sodium hexametaphosphate solution, the passivation layer problem of magnesium-based hydrolysis hydrogen production materials was solved, achieving rapid response hydrolysis hydrogen production after long-term storage.
Patent Information
- Application Number
- CN202511170864.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-21
- Publication Date
- 2025-11-11
AI Technical Summary
Magnesium-based hydrolysis hydrogen production materials are easily hindered by the passivation layer of by-products during the hydrolysis process, and are difficult to respond quickly to hydrogen production after long-term storage, resulting in slower reaction kinetics and reduced hydrogen production efficiency.
CeNb2O7 bimetallic oxide was prepared by a high-temperature solid-state method. By combining EDTA-2Na and sodium hexametaphosphate solution, the oxide layer on the surface of magnesium-based materials was broken through complexation and chelation, which promoted electron transfer and hydrolysis reactions.
This technology enables magnesium-based materials to rapidly respond to hydrolysis for hydrogen production even after long-term storage and transportation, improving the hydrogen production rate and yield, and making it suitable for industrial production.
Smart Images
Figure CN120922825A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to an antioxidant waste magnesium alloy-aqueous solution hydrogen production system and its preparation method, belonging to the technical field of hydrogen production materials and waste magnesium alloy recycling. Background Technology
[0002] Metal hydrolysis hydrogen production materials are an emerging decentralized hydrogen source that can react with water on-site at ambient temperature and pressure to produce hydrogen, directly driving fuel cells and eliminating the need for storage and transportation, thus enabling on-site generation and immediate utilization of hydrogen. Currently, magnesium is the most promising metallic material for hydrolysis hydrogen production, as magnesium-based materials are abundant, low-cost, have mild reaction conditions, environmentally friendly byproducts, and a high theoretical hydrogen yield. The hydrolysis reactions of metallic magnesium and magnesium hydride can produce 8.2 wt% and 15.2 wt% hydrogen (including water mass), respectively. From a thermodynamic perspective, the enthalpy changes of the Mg and MgH2 hydrolysis reactions are -354 kJ·mol⁻¹, respectively. -1 and -277kJ·mol -1 The only byproduct of hydrolysis is magnesium hydroxide, Mg(OH)₂. Mg(OH)₂ is harmless to humans and does not pollute the environment. However, Mg(OH)₂ rapidly precipitates on the surface of Mg, forming a dense passivation layer that hinders the full contact between unreacted substances and the solution, leading to slower reaction kinetics and, in severe cases, direct cessation of the reaction. This reduces the actual hydrogen production and conversion efficiency of the material, making it difficult to achieve its high theoretical value. Therefore, reducing the impact of the Mg(OH)₂ passivation layer on the hydrolysis reaction is a key focus in the research and development of magnesium-based hydrolysis materials. High-energy ball milling to refine the size of magnesium-based materials is an effective method to accelerate their hydrolysis for hydrogen production. Adding a catalyst during ball milling can effectively inhibit the formation of a continuous Mg(OH)₂ passivation layer on the surface of the refined particles. However, the ball-milled magnesium-based particles are easily oxidized in practical applications with mobile hydrogen sources, forming a passivation layer such as MgO on the surface, making it difficult to react quickly with water. Therefore, it is still necessary to solve the key problems of stable storage and transportation of magnesium-based particles and rapid hydrogen production after storage.
[0003] This invention first prepares CeNb₂O₇ bimetallic oxide using a high-temperature solid-state method. The abundant oxygen vacancies in CeNb₂O₇ bimetallic oxide prevent severe internal oxidation of the magnesium-based particles after high-energy ball milling during long-term storage and transportation. Simultaneously, Ce ions, Nb ions, and oxygen vacancies accelerate electron transfer, thereby accelerating the hydrolysis hydrogen production rate. EDTA is then used as a catalyst. 4- With the complexation and chelation effects of phosphate groups, and equipped with a mixed solution of disodium ethylenediaminetetraacetate (EDTA-2Na), sodium hexametaphosphate, and sodium chloride, the magnesium-based hydrogen production composite material can still rapidly respond to hydrolysis to produce hydrogen even after long-term storage and transportation. Summary of the Invention
[0004] The purpose of this invention is to address the key problems of magnesium-based hydrolysis hydrogen production materials being easily interrupted by byproducts during hydrolysis and failing to respond quickly to hydrogen production after long-term storage. This invention provides a method for preparing an oxidation-resistant waste magnesium alloy-aqueous solution hydrogen production system that enables rapid hydrolysis and continues to hydrolyze rapidly even after long-term storage and transportation. First, CeNb₂O₇ bimetallic oxide is prepared using a high-temperature solid-state method. The abundant oxygen vacancies in CeNb₂O₇ bimetallic oxide prevent severe oxidation inside the nanoparticles, while simultaneously accelerating electron transfer and thus accelerating the hydrolysis hydrogen production rate.
[0005] A mixed solution was prepared to enable the magnesium-based composite hydrogen production material to still respond rapidly to hydrolysis for hydrogen production after long-term storage and transportation. This was achieved using EDTA formed by dissolving disodium ethylenediaminetetraacetate (EDTA-2Na) in water. 4- Continuously "grabbing" Mg 2+ The formation of stable complexes will continuously break down the magnesium oxide "Mg" on the surface of waste magnesium alloys. 2+ The "dissociation-equilibrium" state is needed to replenish the complexed Mg. 2+ The MgO on the surface of magnesium oxide will continue to react with water and release Mg. 2+ Ultimately, the solid MgO that was originally attached to the surface of the object will gradually transform into soluble [Mg-EDTA] through a cycle of "dissociation → complexation". 2- Upon entering the water, the exposed fresh metal surface continuously participates in the hydrolysis reaction to produce hydrogen. After hydrolysis, sodium hexametaphosphate slightly adjusts the pH of the aqueous solution (making it weakly alkaline), providing more suitable conditions for the dissolution of magnesium oxide (MgO). This promotes the initial reaction of MgO with water to form magnesium hydroxide Mg(OH)₂, which further dissociates into Mg²⁺. 2+ On the other hand, the phosphate ions produced by hydrolysis can react with Mg. 2+ Combined, reducing the amount of free Mg in the solution. 2+ The concentration of MgO disrupts the aforementioned dissociation equilibrium, driving the continuous transformation of MgO from the solid state to the ionic state. In the long-chain structure of sodium hexametaphosphate, multiple phosphate groups can react with the dissociated MgO. 2+ Forming soluble chelates to prevent Mg from forming 2+ They recombine to form Mg(OH)2 or MgO precipitates.
[0006] Meanwhile, this invention provides an antioxidant waste magnesium alloy-aqueous solution hydrogen production system.
[0007] Meanwhile, this invention provides an application of an antioxidant waste magnesium alloy-aqueous solution hydrogen production system in hydrogen production materials.
[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for preparing an antioxidant waste magnesium alloy-aqueous solution hydrogen production system includes the following steps: Step 1: First, place the weighed niobium pentoxide (Nb2O5) and cerium dioxide (CeO2) into a ball mill jar and perform continuous long-term low-energy ball milling and short-term high-energy ball milling respectively. Step 2: Calcine the above mixed powder at a temperature of 1150°C to 1250°C for 9 to 12 hours to prepare CeNb2O7 material; Step 3: After mechanically crushing the waste magnesium alloy, it is subjected to high-energy ball milling with the CeNb2O7 obtained above to prepare waste magnesium alloy-CeNb2O7 composite hydrogen production particles, which are then pressed into tablets. After mechanical crushing, the particle size of the waste magnesium alloy is less than 3 mm, and the particle size range of the CeNb2O7 material obtained is 1~30 micrometers.
[0009] Step four, solution preparation. The aqueous solution used in this invention is an aqueous solution formed by dissolving disodium ethylenediaminetetraacetate (EDTA-2Na), sodium hexametaphosphate (NaPO3)6, and sodium chloride in water.
[0010] Preferably, in step one, the atomic ratio of niobium pentoxide (Nb₂O₅) and cerium dioxide (CeO₂) is 1:1 (mass ratio is 1.56:1), the ball-to-material ratio is 20:1 to 30:1, the low-energy ball milling speed is 150 to 200 rpm, and the continuous ball milling time is 40 to 50 hours; the high-energy ball milling speed is 800 to 1200 rpm, and the continuous ball milling time is 1 to 2 hours.
[0011] Preferably, in step two, the mixed powder after ball milling in step one is first placed in a muffle furnace for calcination, with a heating rate of 5~10°C / min, and held at the predetermined temperature for 9~12 hours.
[0012] Preferably, in step three, the waste magnesium alloy includes models such as AZ91, AZ31, AM60, ZK61, and ZK60, and the mechanical crushing methods used include dry turning, metal pulverizer crushing, and mechanical ball mill crushing.
[0013] The CeNb₂O₇ mass fraction is 3%~8%. Waste magnesium alloy scraps and CeNb₂O₇ are weighed according to a specific mass ratio and then subjected to high-energy ball milling under argon protection. The ball-to-material ratio is 20:1~30:1, and the milling time is 1.5~2 hours. Tableting is then performed using a tablet press at a pressure of 10~20 MPa, resulting in a material diameter of 10~15 mm and a thickness of 2~6 mm.
[0014] Preferably, in step four, the aqueous solution contains 2% to 3% disodium ethylenediaminetetraacetate (EDTA-2Na), 2% to 3% sodium hexametaphosphate (NaPO3)6, and 3.5% sodium chloride.
[0015] The present invention discloses an antioxidant waste magnesium alloy-aqueous solution hydrogen production system, which produces 705~738 mL / g of hydrogen at room temperature, with an initial hydrogen production rate of 1.58~2.38 mL / g. -1 min -1 After five minutes of reaction, the hydrogen production rate can reach 3.41~4.75 mL g. -1 min -1 .
[0016] The present invention relates to the application of an antioxidant waste magnesium alloy-aqueous solution hydrogen production system in hydrogen production materials.
[0017] Compared with the prior art, the beneficial effects of the present invention are: (1) The CeNb2O7 bimetallic oxide synthesized by the high-temperature solid-state method of this invention contains a large number of oxygen vacancies, which can effectively suppress the internal oxidation of magnesium-based hydrogen production composite materials during long-term storage and transportation, and at the same time significantly accelerate the electron transfer during the hydrolysis process, thereby accelerating the hydrogen production rate.
[0018] (2) The EDTA in the mixed solution of disodium ethylenediaminetetraacetate (EDTA-2Na), sodium hexametaphosphate (NaPO3)6 and sodium chloride prepared in this invention 4- Phosphate ions can effectively eliminate MgO in magnesium-based composite hydrogen production materials, allowing the composite material to still rapidly hydrolyze and produce hydrogen after long-term storage, thus obtaining an antioxidant waste magnesium alloy-aqueous solution hydrogen production system.
[0019] (3) Magnesium alloys are widely used in 3C, automotive, and aerospace fields due to their excellent properties such as lightweight, high strength, and electromagnetic shielding. Examples include engine blocks, transmission system components, seat frames, electronic product casings, and brackets. However, magnesium alloy materials generate waste magnesium alloys after processing, use, or disposal. This includes large amounts of scrap, chips, and gate material generated from cutting, casting, and forging processes, scrapped automotive parts, and discarded electronic product casings and brackets. This invention uses waste magnesium alloys as raw materials, achieving low-cost recycling and reuse of waste magnesium alloys, especially low-quality magnesium alloys.
[0020] In summary, the present invention has a simple preparation process, low cost, and achieves efficient utilization of waste magnesium alloys. The prepared composite hydrogen production material can be stably stored and transported and can quickly respond to hydrolysis to produce hydrogen, making it suitable for industrial production. Attached Figure Description
[0021] Figure 1 The image shows the SEM morphology of the Nb2O5+CeO2 particles after ball milling in Example 1 of this invention. Figure 2This is an elemental surface scan distribution diagram of the Nb2O5+CeO2 particles after ball milling in Example 1 of the present invention; Figure 3 This is a morphology image of the waste AZ91D magnesium alloy-6%CeNb2O7 composite particles after ball milling in Example 1 of the present invention; Figure 4 This is a morphology image of the waste ZK60 magnesium alloy-8%CeNb2O7 composite particles after ball milling in Example 2 of the present invention. Figure 5 This is a morphology diagram of the waste AZ31 magnesium alloy-3%CeNb2O7 composite particles after ball milling in Example 3 of the present invention. Detailed Implementation
[0022] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The following embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Example 1
[0023] A method for preparing an antioxidant waste magnesium alloy-aqueous solution hydrogen production system includes the following steps: After weighing Nb₂O₅ and CeO₂ at a mass ratio of 1.56:1, they were placed in a ball mill jar for long-term low-energy ball milling at a ball-to-material ratio of 20:1 and a ball mill speed of 200 rpm for 50 hours. This was followed by 1 hour of high-energy ball milling at a speed of 1000 rpm. Figure 1 The SEM morphology of the ball-milled particles is shown. Figure 2 The image shows the elemental surface scan distribution of the ball-milled particles. As can be seen, the CeO2 and Nb2O5 particles are uniformly mixed and have small sizes after ball milling. The ball-milled particles were then placed in a muffle furnace at room temperature for high-temperature calcination at a heating rate of 5°C / min, reaching 1200°C and holding for 9 hours to prepare CeNb2O7 bimetallic oxide. Collected waste AZ91D magnesium alloy cuttings (particle size range: 1-3 mm) were mixed with 6% CeNb2O7 bimetallic oxide (particle size range: 1-30 μm) and then ball-milled under argon protection at a ball-to-material ratio of 20:1 for 2 hours. Figure 3The image shows the SEM morphology of the ball-milled waste AZ91D magnesium alloy-6%CeNb2O7 composite particles. As can be seen, the fine CeNb2O7 particles are uniformly distributed on the surface of the waste magnesium alloy, effectively preventing further oxidation within the alloy. Simultaneously, during hydrolysis, they form a galvanic cell with the waste magnesium alloy, accelerating electron transfer and the hydrolysis rate of the matrix. The ball-milled composite particles were then compressed into tablets using a tablet press at a pressure of 20 MPa. The resulting material has a diameter of 10 mm and a thickness of 2 mm. After the prepared waste AZ91D magnesium alloy-6%CeNb2O7 composite material tablets were placed in air for 120 hours, they were then placed in a prepared mixed solution of disodium ethylenediaminetetraacetate (EDTA-2Na), sodium hexametaphosphate (NaPO3)6, and sodium chloride. The concentrations of disodium ethylenediaminetetraacetate (EDTA-2Na), sodium hexametaphosphate (NaPO3)6, and sodium chloride were 3.5%. The composite material tablets exhibited rapid hydrogen production, with an initial hydrogen production rate of 2.27 mL g. -1 min -1 After five minutes of reaction, the hydrogen production rate can reach 4.12 mL g. -1 min -1 .
[0024] The composite material tablets of this invention were prepared using novel AZ91D magnesium alloy, such as the novel AZ91D magnesium alloy-6%CeNb2O7 composite material tablet (prepared using the same method as in this embodiment). The initial hydrogen production rate in a mixed solution of 3% disodium ethylenediaminetetraacetate (EDTA-2Na), 3% sodium hexametaphosphate (NaPO3)6, and 3.5% sodium chloride was 2.43 mL g. -1 min -1 After five minutes of reaction, the hydrogen production rate was 4.33 mL g. -1 min -1 .
[0025] The hydrogen production rate of the waste AZ91D magnesium alloy-6%CeNb2O7 composite material tablet in this embodiment is comparable to that of the new AZ91D magnesium alloy-6%CeNb2O7 composite material tablet, which is about 93% to 95% of the hydrogen production rate of the new AZ91D magnesium alloy-6%CeNb2O7 composite material tablet.
[0026] Whether it's brand new AZ91D magnesium alloy or scrap AZ91D magnesium alloy, if it's not ball-milled with CeNb2O7 but is simply pure AZ91D magnesium alloy, its hydrogen production rate in sodium chloride solution and mixed solutions of disodium ethylenediaminetetraacetate, sodium hexametaphosphate (NaPO3)6, and sodium chloride is very slow. The hydrogen production rate in a 3.5% sodium chloride solution remains at approximately 0.086 mLg. -1 min -1The hydrogen production rate in a mixed solution of 3% disodium ethylenediaminetetraacetate, 3% sodium hexametaphosphate (NaPO3)6, and 3.5% sodium chloride remained at approximately 0.1 mL g. -1 min -1 .
[0027] Total hydrogen production: 1 g of brand new AZ91D magnesium alloy-6%CeNb2O7 composite material tablets produces ~761 mL of hydrogen at room temperature, while 1 g of waste AZ91D magnesium alloy-6%CeNb2O7 composite material tablets in this embodiment produces ~722 mL of hydrogen at room temperature, which is 95% of the hydrogen production of brand new AZ91D magnesium alloy-6%CeNb2O7 composite material tablets.
[0028] The antioxidant waste magnesium alloy-aqueous solution hydrogen production system obtained in this embodiment has a hydrogen production rate of ~722 mL / g at room temperature, and an initial hydrogen production rate of up to 2.27 mL / g. -1 min -1 After five minutes of reaction, the hydrogen production rate can reach 4.12 mLg. -1 min -1 .
[0029] This embodiment demonstrates the application of an antioxidant waste magnesium alloy-aqueous solution hydrogen production system in hydrogen production materials. Example 2
[0030] A method for preparing an antioxidant waste magnesium alloy-aqueous solution hydrogen production system includes the following steps: After weighing Nb₂O₅ and CeO₂ at a mass ratio of 1.56:1, they were placed in a ball mill jar for long-term low-energy ball milling at a ball-to-material ratio of 20:1 and a mill speed of 150 rpm for 50 hours. This was followed by 1 hour of high-energy ball milling at a speed of 1200 rpm. The milled particles were then placed in a muffle furnace at room temperature for high-temperature calcination at a heating rate of 10°C / min, reaching 1150°C and holding for 10 hours to prepare CeNb₂O₇ bimetallic oxide. Collected waste ZK60 magnesium alloy cuttings were mixed with 8% CeNb₂O₇ bimetallic oxide (waste ZK60 magnesium alloy cutting particle size range: 1~3 mm, CeNb₂O₇ particle size range: 1~30 μm) and then subjected to high-energy ball milling under argon protection at a ball-to-material ratio of 20:1 for 2 hours. Figure 4The image shows the morphology of the ball-milled waste ZK60 magnesium alloy-8%CeNb2O7 composite particles. As can be seen, fine CeNb2O7 particles are uniformly distributed on the surface of the waste magnesium alloy. The ball-milled composite particles were then compressed into tablets using a tablet press at a pressure of 10 MPa. The resulting material had a diameter of 13 mm and a thickness of 2.5 mm. After the prepared waste AZ91D magnesium alloy-8%CeNb2O7 composite tablets were placed in air for 144 hours, they were then immersed in a mixed solution of disodium ethylenediaminetetraacetate (EDTA-2Na), sodium hexametaphosphate (NaPO3)6, and sodium chloride. The concentrations of EDTA-2Na were 2%, sodium hexametaphosphate (NaPO3)6 were 3%, and sodium chloride was 3.5%. The composite tablets exhibited rapid hydrogen production, with an initial hydrogen production rate of 2.38 mL g. -1 min -1 After five minutes of reaction, the hydrogen production rate can reach 4.75 mL g. -1 min -1 .
[0031] The antioxidant waste magnesium alloy-aqueous solution hydrogen production system obtained in this embodiment has a hydrogen production rate of ~738 mL / g at room temperature, and an initial hydrogen production rate of up to 2.38 mL / g. -1 min -1 After five minutes of reaction, the hydrogen production rate can reach 4.75 mLg. -1 min -1 .
[0032] This embodiment demonstrates the application of an antioxidant waste magnesium alloy-aqueous solution hydrogen production system in hydrogen production materials. Example 3
[0033] A method for preparing an antioxidant waste magnesium alloy-aqueous solution hydrogen production system includes the following steps: After weighing Nb₂O₅ and CeO₂ at a mass ratio of 1.56:1, they were placed in a ball mill jar for long-term low-energy ball milling at a ball-to-material ratio of 30:1 and a mill speed of 200 rpm for 40 hours. This was followed by 2 hours of high-energy ball milling at a speed of 800 rpm. The milled particles were then placed in a muffle furnace at room temperature for high-temperature calcination at a heating rate of 8°C / min, reaching 1250°C and holding for 12 hours to prepare CeNb₂O₇ bimetallic oxide. Collected waste AZ91D magnesium alloy cuttings were mixed with 3% CeNb₂O₇ bimetallic oxide (waste AZ91D magnesium alloy cuttings with a particle size less than 3 mm, CeNb₂O₇ particle size range: 1~30 μm) and then subjected to high-energy ball milling under argon protection at a ball-to-material ratio of 30:1 for 1.5 hours. Figure 5The image shows the morphology of the ball-milled waste AZ31 magnesium alloy-3%CeNb2O7 composite particles. As can be seen from the image, fine CeNb2O7 particles are uniformly distributed on the surface of the waste magnesium alloy. The ball-milled composite particles were then compressed into tablets using a tablet press at a pressure of 15 MPa. The resulting material had a diameter of 15 mm and a thickness of 6 mm. After the prepared waste AZ31 magnesium alloy-3%CeNb2O7 composite tablets were placed in air for 144 hours, they were then immersed in a prepared mixed solution of disodium ethylenediaminetetraacetate (EDTA-2Na), sodium hexametaphosphate (NaPO3)6, and sodium chloride. The concentrations of EDTA-2Na, sodium hexametaphosphate (NaPO3)6, and sodium chloride were 2% and 3.5%, respectively. The composite tablets exhibited rapid hydrogen production, with an initial hydrogen production rate of 1.58 mL g. -1 min -1 After five minutes of reaction, the hydrogen production rate can reach 3.41 mL g. -1 min -1 .
[0034] The antioxidant waste magnesium alloy-aqueous solution hydrogen production system obtained in this embodiment has a hydrogen production rate of ~705 mL / g at room temperature, and an initial hydrogen production rate of up to 1.58 mL / g. -1 min -1 After five minutes of reaction, the hydrogen production rate can reach 3.41 mLg. -1 min -1 .
[0035] This embodiment demonstrates the application of an antioxidant waste magnesium alloy-aqueous solution hydrogen production system in hydrogen production materials.
[0036] Comparative Example 1
[0037] The only difference between this comparative example and Example 1 is that the prepared aqueous solution was a 3.5% NaCl solution, without the addition of any disodium ethylenediaminetetraacetate or sodium hexametaphosphate, and the initial hydrogen production rate of the prepared composite material tablets after being placed in air for 120 hours was only 0.23 mL g. -1 min -1 After five minutes of reaction, the hydrogen production rate was 0.58 mL g. -1 min -1 .
[0038] It should be understood that, in order to simplify this disclosure and aid in understanding one or more of the various aspects of the invention, features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the above description of exemplary embodiments of the invention. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed invention requires more features than expressly recited in each claim. Rather, as reflected in the claims, inventive aspects lie in fewer than all the features of the foregoingly disclosed embodiments. Therefore, the claims, following the detailed description, are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.
[0039] Although the invention has been described with reference to a limited number of embodiments, those skilled in the art will understand from the foregoing description that other embodiments are conceivable within the scope of the invention described herein. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and instructional purposes, and not for the purpose of interpreting or limiting the subject matter of the invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the invention is illustrative and not restrictive, and the scope of the invention is defined by the appended claims.
[0040] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing an antioxidant waste magnesium alloy-aqueous solution hydrogen production system, characterized in that, Includes the following steps: Step 1: Niobium pentoxide and cerium dioxide with a mass ratio of 1.56:1 are placed in a ball mill jar and subjected to continuous long-term low-energy ball milling and short-term high-energy ball milling respectively to obtain mixed powder; Step 2: Calcine the above mixed powder at a temperature of 1150°C to 1250°C for 9 to 12 hours to prepare CeNb2O7 material; Step 3: After mechanically crushing the waste magnesium alloy, it is subjected to high-energy ball milling with CeNb2O7 material with a mass fraction of 3%~8% to prepare waste magnesium alloy-CeNb2O7 composite hydrogen production particles, which are then pressed into tablets. Step 4, prepare the aqueous solution: dissolve 2%~3% disodium ethylenediaminetetraacetate, 2%~3% sodium hexametaphosphate, and 3.5% sodium chloride in water to form an aqueous solution.
2. The preparation method according to claim 1, characterized in that, In step one, the ball-to-material ratio is 20:1 to 30:1; the low-energy ball mill speed is 150 to 200 rpm, and the continuous ball milling time is 40 to 50 hours; the high-energy ball mill speed is 800 to 1200 rpm, and the continuous ball milling time is 1 to 2 hours.
3. The preparation method according to claim 1, characterized in that, In step two, the heating rate of calcination is 5~10°C / min.
4. The preparation method according to claim 1, characterized in that, In step three, the scrap magnesium alloys include magnesium alloy scraps of models AZ91, AZ31, AM60, ZK61, and ZK60. Magnesium alloy scrap includes scrap, chips, and gate material generated from cutting, casting, or forging operations; scrapped automotive parts; and casings or brackets of discarded electronic products.
5. The preparation method according to claim 1, characterized in that, In step three, mechanical crushing methods include dry turning, metal pulverizer crushing, or mechanical ball mill crushing.
6. The preparation method according to claim 1, characterized in that, In step three, the high-energy ball milling process is as follows: high-energy ball milling is carried out under argon protection, the ball-to-material ratio is 20:1 to 30:1, and the milling time is 1.5 to 2 hours.
7. The preparation method according to claim 1, characterized in that, In step three, the tableting process is as follows: tablets are pressed using a tablet press at a pressure of 10~20MPa, and the resulting material has a diameter of 10~15mm and a thickness of 2~6mm.
8. An antioxidant waste magnesium alloy-aqueous solution hydrogen production system obtained by the preparation method according to any one of claims 1 to 7.
9. The antioxidant waste magnesium alloy-aqueous solution hydrogen production system according to claim 8, characterized in that, The hydrogen production at room temperature is 705–738 mL / g, and the initial hydrogen production rate can reach 1.58–2.38 mL / g. -1 min -1 After five minutes of reaction, the hydrogen production rate can reach 3.41~4.75 mL g. -1 min -1 .
10. The application of the antioxidant waste magnesium alloy-aqueous solution hydrogen production system according to claim 8 in hydrogen production materials.