Regeneration method of pulverization polymer-hydrogen storage alloy composite material poisoned by impurity gas

Abstract

The invention discloses a regeneration method of a pulverization polymer-hydrogen storage alloy composite material poisoned by foreign gas, and the pulverization polymer-hydrogen storage alloy composite material poisoned by foreign gas comprises a hydrogen storage alloy and a polymer partially coating the hydrogen storage alloy, the exposed surface, which is not coated by the polymer, of the hydrogen storage alloy is partially or completely adsorbed and / or covered by impurity gas; the regeneration method comprises the following steps: purging the pulverization polymer-hydrogen storage alloy composite material poisoned by impurity gas by using flowing hydrogen at 50-200 DEG C to desorb the impurity gas, so as to obtain an intermediate repair material; and the middle repairing material is subjected to dynamic vacuum heating, so that the polymer is softened and thermally deformed and then spreads and flows again, the coating rate of the polymer on the hydrogen storage alloy is increased, secondary coating is completed, and then the regenerated polymer-hydrogen storage alloy composite material is obtained through cooling. The method has the advantages of being simple in technological process, mild in operation temperature, easy to apply on a large scale and the like, and the long-acting anti-poisoning performance of the hydrogen storage alloy can be remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of polymer-hydrogen storage alloy composite materials, and more specifically to a method for regenerating pulverized polymer-hydrogen storage alloy composite materials poisoned by impurity gases. Background Technology

[0002] Solid-state hydrogen storage is one of the mainstream hydrogen storage technologies, with core advantages such as high safety, high volumetric hydrogen storage density, mild operating conditions, material diversity and designability, making it suitable for various application scenarios.

[0003] In practical applications, impurity gases preferentially adsorb onto the active sites on the surface of hydrogen storage materials such as alloys, causing surface poisoning effects and leading to irreversible capacity decay. Furthermore, as the number of hydrogen absorption and desorption cycles increases, the pulverization of hydrogen storage materials such as alloys intensifies, further deteriorating the hydrogen storage performance.

[0004] Polymer composite systems exhibit unique advantages in improving the anti-poisoning properties of hydrogen storage materials.

[0005] For example, the patent specification with publication number CN110316698A discloses a PMMA organic-coated one-dimensional magnesium nanoparticle hydrogen storage material and its preparation method, including nano-Mg particles prepared by liquid-phase reduction method and PMMA and DMF solvent. The nano-Mg is ultrasonically dispersed in the PMMA solution of DMF, and the organic coating of PMMA is completed by electrospinning. The nano-Mg particles prepared by this method are small in size, have a large specific surface area, and have high surface activity. The diffusion of hydrogen molecules in them is short-range diffusion. PMMA, as a hydrophobic, oxygen-phobic, and hydrogen-permeable organic material, can coat the nano-Mg particles, which can prevent water vapor and oxygen in the air from contacting the nano-Mg particles, while not affecting the normal hydrogen absorption and desorption process, and can effectively prevent the formation of a surface passivation film.

[0006] For example, patent specification CN116101974A discloses a polymer-doped aluminum hydride hydrogen storage material and its preparation method, including a composite hydrogen storage material composed of a light metal hydride and a polymer. The light metal hydride includes at least one of LiH, MgH2, or AlH3, and the polymer includes at least one of PMMA, ABS, or PVP. The mass ratio of the light metal hydride to the polymer is 1:0.1~100. The preparation method of the polymer-doped aluminum hydride hydrogen storage material prepared by this patent technology is simple, easy to control, and has good controllability. The additive cost is low, and the material after ball milling is pressed into a disc shape under high pressure, which can effectively increase space utilization.

[0007] None of the patented technologies mentioned above involve hydrogen storage alloys. In fact, current commercially available solid-state hydrogen storage materials are mainly AB5-type (LaNi5) and AB2-type (TiCr2, TiMn2) alloys. Among them, AB2-type alloys have become a research hotspot due to their excellent comprehensive hydrogen storage performance, such as high hydrogen storage density, adjustable hydrogen absorption / desorption plateau pressure, and mild hydrogen absorption / desorption temperature. However, their widespread application in scenarios using industrial gray hydrogen or low-purity hydrogen faces serious challenges.

[0008] In existing composite systems, hydrogen storage alloy matrices are prone to pulverization during repeated hydrogen absorption and desorption cycles. Although strengthening the interfacial bonding between the coating layer and the matrix can improve the anti-poisoning performance during the cycle to some extent, the fresh surface generated by pulverization is often exposed to the hydrogen environment containing impurity gases because it is not effectively covered by the polymer. The poisoning effect of impurity gases on such new interfaces is still difficult to suppress. There is no effective solution for regenerating the anti-poisoning performance of composite hydrogen storage material powder after hydrogen absorption and desorption cycles. Summary of the Invention

[0009] To address the aforementioned technical problems and shortcomings in the field, this invention provides a method for regenerating a pulverized polymer-hydrogen storage alloy composite material poisoned by impurity gases. First, the material is purged with flowing hydrogen under mild temperature conditions, causing the impurity gases adsorbed and / or covering the fresh surface of the material generated by the hydrogen absorption and desorption cycle to desorb. Then, under mild temperature conditions, the polymer coating layer is thermally deformed by heat treatment, causing the polymer film to spread and flow, thereby achieving secondary coating of the repulverized powder surface.

[0010] The specific technical solution is as follows: A method for regenerating a pulverized polymer-hydrogen storage alloy composite material poisoned by impurity gases, wherein the pulverized polymer-hydrogen storage alloy composite material poisoned by impurity gases includes a hydrogen storage alloy and a polymer partially coating the hydrogen storage alloy, and the exposed surface of the hydrogen storage alloy not coated by the polymer is partially or completely adsorbed and / or covered by impurity gases. The regeneration method includes the following steps: (1) The powdered polymer-hydrogen storage alloy composite material poisoned by the impurity gas is purged with flowing hydrogen at 50~200℃ (e.g., 120℃, etc.) to desorb the impurity gas and obtain intermediate repair material; (2) The intermediate repair material is dynamically vacuum heated to soften and thermally deform the polymer and then spread and flow again, thereby increasing the coating rate of the polymer on the hydrogen storage alloy, completing the secondary coating, and then cooling to obtain the regenerated polymer-hydrogen storage alloy composite material.

[0011] Furthermore, the impurity gas includes one or more of CO, CO2, N2, and Ar.

[0012] The regeneration method of this invention is particularly applicable to composite hydrogen storage materials that have undergone hydrogen absorption and desorption cycling and pulverization in a hydrogen atmosphere containing trace amounts of impurity gases. Furthermore, the poisoning environment of the pulverized polymer-hydrogen storage alloy composite material poisoned by impurity gases is a hydrogen atmosphere with an impurity gas content not exceeding 500 ppmv (e.g., 20 ppmv).

[0013] Furthermore, the polymer includes one or more of polymethyl methacrylate (PMMA), polyethylene (PE), polypropylene (PP), and polycaprolactone (PCL). Even further, the polymer includes both PMMA and polypropylene. PMMA is a flexible polymer, and polypropylene is a rigid polymer; their synergistic coating forms a gradient coating structure on the surface of the hydrogen storage alloy, which can significantly improve the hydrogen absorption and desorption cycle performance and resistance to poisoning of the hydrogen storage alloy. Even further, the mass ratio of PMMA to polypropylene is 10:1 to 100, preferably 1:1.

[0014] Furthermore, the hydrogen storage alloy includes at least one of AB5-type hydrogen storage alloy and AB2-type hydrogen storage alloy, preferably one or more of LaNi5-type hydrogen storage alloy, TiMn2-type hydrogen storage alloy, and TiCr2-type hydrogen storage alloy, and more preferably includes Ti 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 Hydrogen storage alloy.

[0015] Furthermore, the mass ratio of the polymer to the hydrogen storage alloy is 1~50:100, preferably 5~20:100.

[0016] Furthermore, the pulverized polymer-hydrogen storage alloy composite material poisoned by impurity gases is wherein the polymer is coated onto the surface of the hydrogen storage alloy by ball milling. Specifically, a one-step ball milling process can be used.

[0017] By optimizing ball milling parameters (such as ball-to-material ratio, ball milling speed, ball milling time, and ball milling media), additives can be uniformly dispersed on the surface of hydrogen storage alloys. Their lubrication effect can significantly reduce the accumulation of internal stress during the ball milling process, reduce the probability of impurity gases entering the material pores, and improve the effective contact interface between hydrogen and hydrogen storage alloys.

[0018] The ball milling is preferably performed under an inert atmosphere. The inert atmosphere refers to a gaseous atmosphere that will not chemically react with the hydrogen storage alloy and the additives, preferably including a nitrogen atmosphere and / or a rare gas atmosphere. The rare gas preferably includes at least one of argon and helium.

[0019] The ball mill is preferably a planetary ball mill or a vibrating ball mill.

[0020] The preferred material for the grinding jar used in the ball mill is one or more of stainless steel, agate, and polytetrafluoroethylene.

[0021] The preferred rotational speed of the ball mill is 100~600 rpm, for example, 400 rpm.

[0022] The preferred ball milling time is 1 to 100 hours, for example, 12 hours.

[0023] The preferred ball-to-material ratio in the ball milling process is 10 to 100:1, such as 40:1.

[0024] In some preferred embodiments, in step (1), the flow rate of the flowing hydrogen purging is 10~200 mL / min, for example 60 mL / min.

[0025] In some preferred embodiments, in step (1), the time for the flowing hydrogen purging is 0.5 to 12 h, for example, 1 h.

[0026] Step (2) of this invention utilizes the viscous flow characteristics of polymers to restore the anti-poisoning properties of materials without the need for additional processing steps or offline material recycling steps.

[0027] Furthermore, in step (2), the temperature of the vacuum heating is greater than or equal to the temperature of the polymer softening heat deformation.

[0028] For different polymers, the temperature of the vacuum heating in step (2) can be adapted to vary. In some preferred embodiments, the temperature of the vacuum heating in step (2) is 50~200°C, for example 120°C.

[0029] In some preferred embodiments, in step (2), the vacuum degree of the vacuum heating is below 0.01 Pa.

[0030] In some preferred embodiments, the time for dynamic vacuum heating in step (2) is 0.5 to 12 h, for example, 1 h.

[0031] Compared with the prior art, the beneficial effects of this invention are as follows: To address the issue of continuous kinetic degradation caused by the pulverization of the hydrogen storage alloy matrix in composite hydrogen storage materials during hydrogen absorption and desorption cycles in a hydrogen atmosphere containing trace amounts of impurities, this invention proposes a regeneration method. This method offers advantages such as a simple process flow, mild operating temperature, and ease of large-scale application, significantly improving the long-term anti-poisoning performance of the hydrogen storage alloy. By optimizing heat treatment parameters (including heating temperature, holding time, and cooling rate), the polymer on the surface of the composite hydrogen storage material after hydrogen absorption and desorption cycles can be re-spread and uniformly cover the surface, effectively mitigating problems such as coating layer detachment and exposure of fresh surfaces caused by pulverization due to lattice stress generated during hydrogen absorption and desorption cycles. Experiments show that the regenerated composite material still maintains excellent hydrogen storage capacity and anti-poisoning ability in a hydrogen atmosphere containing impurities. Attached Figure Description

[0032] Figure 1 The following are the structural formula, X-ray diffraction (XRD) pattern, and Fourier transform infrared (FTIR) spectrum of PMMA (polymethyl methacrylate).

[0033] Figure 2 The following are the structural formula, XRD pattern, and FTIR spectrum of PE (polyethylene).

[0034] Figure 3 The following are the structural formula, XRD pattern, and FTIR spectrum of PP (polypropylene).

[0035] Figure 4 The following are the structural formula, XRD pattern, and FTIR spectrum of PCL (polycaprolactone).

[0036] Figure 5 For Ti 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 As-cast alloys and different polymers-Ti 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 XRD pattern of alloy composite hydrogen storage material.

[0037] Figure 6 For (a) ball-milled Ti 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2Alloy, 5 wt.% PMMA(b), 5 wt.% PP(c), 5 wt.% PE(d), 5 wt.% PCL(e), 2.5 wt.%PMMA+2.5 wt.%PP(f)@Ti 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 Scanning electron microscope (SEM) image of composite hydrogen storage materials.

[0038] Figure 7 The product is 2.5 wt.% PMMA + 2.5 wt.% PP@Ti after 10 hydrogen adsorption / desorption cycles in a hydrogen atmosphere containing trace impurities. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 SEM image of composite hydrogen storage material.

[0039] Figure 8 The regenerated product is 2.5 wt.% PMMA + 2.5 wt.% PP@Ti. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 SEM image of composite hydrogen storage material.

[0040] Figure 9 The composition is 2.5 wt.% PMMA + 2.5 wt.% PP@Ti before and after regeneration. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 kinetic diagram of CO and CO2 poisoning hydrogen absorption of composite hydrogen storage materials. Detailed Implementation

[0041] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Operating methods not specifically specified in the following embodiments are generally performed under conventional conditions or as recommended by the manufacturer.

[0042] Figure 1 The image shows the structural formula, XRD pattern, and FTIR spectrum of PMMA (polymethyl methacrylate). Figure 1As shown in (b) the XRD pattern, PMMA is an amorphous organic material with only one amorphous diffraction peak around 2θ=15°. Figure 1 (c) shows the FTIR spectrum of PMMA at 3400 cm⁻¹. -1 The absorption peak is the OH stretching vibration peak, at 2900 cm⁻¹. -1 The peak at 1750 cm⁻¹ represents the stretching vibration of methyl (-CH₃) and methylene (-CH₂-). -1 The characteristic absorption peak of C=O in the ester group is 1500~1300 cm⁻¹. -1 The absorption peaks are for the bending vibrations of the CH bonds in methyl and methylene groups, ranging from 1300 to 1100 cm⁻¹. -1 The characteristic absorption peak of COC in the ester group, and Figure 1 The structure of (a) is consistent.

[0043] Figure 2 The structure, XRD pattern, and FTIR spectrum of PE (polyethylene) are shown. Figure 2 (b) shows that PE has two diffraction peaks at 21.2° and 23.5°. Figure 2 (c) shows the FTIR spectrum at 2920 cm⁻¹. -1 2850 cm -1 There is an absorption peak at 1450 cm⁻¹ for the stretching vibration of methylene-CH₂-. -1 There is an absorption peak at 720 cm⁻¹ for the bending vibration of the CH bond in -CH₂-. -1 The absorption peak at this location is the in-plane rocking vibration of -CH2-, and... Figure 2 The structure of (a) is consistent.

[0044] Figure 3 The structure, XRD pattern, and FTIR spectrum of PP (polypropylene) are shown. Figure 3 (b) shows that PP has four distinct diffraction peaks at 14.1°, 16.8°, 18.4° and 21.8°. Figure 3 (c) shows the FTIR spectrum at 2900–2800 cm⁻¹. -1 There are absorption peaks at 1500~1300 cm⁻¹ for the stretching vibrations of methyl CH₃- and methylene CH₂-. -1 The absorption peak at this location is due to the CH bond bending vibration. Figure 3 The structure of (a) is consistent.

[0045] Figure 4 The structure, XRD pattern, and FTIR spectrum of PCL (polycaprolactone) are shown. Figure 4 (b) shows that PCL has three relatively obvious diffraction peaks at 21.5°, 22.4° and 24.1°. Figure 4(c) shows the FTIR spectrum from 3000 to 2900 cm⁻¹. -1 The peak at 1750 cm⁻¹ represents the stretching vibration peak of the CH bond. -1 The characteristic absorption peak for C=O in the ester group is 1500~1300 cm⁻¹. -1 The absorption peak for CH bond bending vibration is 1300–1150 cm⁻¹. -1 The characteristic absorption peak of COC in the ester group, and Figure 4 The structure of (a) is consistent.

[0046] Example 1: According to Ti 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 The alloy formula is prepared by mixing and melting various elemental metal raw materials to obtain Ti. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 Alloy. The specific parameters and conditions for smelting are those conventional techniques in this field.

[0047] Use 5 wt.% (in Ti) respectively 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 The alloy comprises 100% PMMA (polymethyl methacrylate), 5 wt.% PP (polypropylene), 5 wt.% PE (polyethylene), 5 wt.% PCL (polycaprolactone), and 2.5 wt.% PMMA + 2.5 wt.% PP as additives, with Ti as the base. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 Using an alloy as the matrix, polymer-doped modified composite hydrogen storage materials were prepared using a planetary ball mill. The raw materials were placed in a ball mill jar at a ball-to-material ratio of 40:1 under argon protection, and the jar was kept sealed. The mill was then ball-milled at 400 rpm for 12 hours. The mill was stopped for 10 minutes after every 30 minutes of operation to prevent overheating inside the jar, and then the mill was reversed. As a control, Ti was used without polymer additives. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V0.2 The alloy was prepared using a planetary ball mill with the same ball milling process parameters, resulting in ball-milled Ti. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 Alloy. After ball milling, remove the hydrogen storage material from the glove box and store it for later use.

[0048] Figure 5 Different polymers-Ti were shown 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 XRD patterns of the alloy composite hydrogen storage material. The ball milling process introduces significant lattice strain and distortion into the alloy, leading to broadening of the diffraction peaks in the ball-milled modified hydrogen storage material. The main diffraction peaks near 43° are significantly broadened and overlap. Due to the low concentration of polymer additives (only 5 wt.%) and their poor crystallinity, the diffraction peaks of the additives are barely visible in the XRD patterns of the ball-milled modified composite hydrogen storage material.

[0049] Figure 6 Ti modified by ball milling 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 SEM images of alloy materials and composite hydrogen storage materials. Figure 6 (a) is pure Ti after ball milling. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 SEM images of the alloys are shown in (b)-(f), representing the SEM images of composite hydrogen storage materials with added PMMA, PP, PE, PCL, and PMMA+PP, respectively. The pure alloy particles are approximately several micrometers in size, with a relatively regular surface morphology and visible cracks, similar to the cracks seen in the SEM images of the alloy after hydrogen absorption / desorption cycles. This is because the alloy is mechanically crushed by external force during ball milling, resulting in particle size reduction and crack formation. The composite hydrogen storage material particles are approximately several micrometers in size, with many smaller particles appearing on the surface; these particles are polymer additives. It is evident that the preferred high-energy ball milling at 400 rpm for 12 hours can effectively form a polymer film on the surface of the alloy particles, achieving relatively complete coating of the alloy particles.

[0050] Example 2: In practical applications, hydrogen storage materials may come into contact with impurity gases after several working cycles. These hydrogen adsorption and desorption cycles cause the alloy to expand and contract in volume, leading to pulverization of the alloy particles and subsequent rupture of the polymer film on the particle surface, affecting its anti-poisoning performance. To investigate the effect of hydrogen adsorption and desorption cycles on the polymer film on the surface of composite hydrogen storage materials, PMMA and PMMA+PP ball-milled modified composite hydrogen storage materials were subjected to 10 hydrogen adsorption and desorption cycles in a hydrogen atmosphere containing trace impurity gas (20 ppm CO2).

[0051] Figure 7 The images show SEM images of PMMA and PMMA+PP ball-milled modified composite hydrogen storage materials after hydrogen absorption and desorption cycles. The white circles in the images represent fine polymer particles on the alloy surface. However, compared to the previous text... Figure 6 Unlike the SEM images, the hydrogen adsorption / desorption cycle causes a certain degree of pulverization of the alloy particles. Newly formed particles do not form a complete polymer film on their surface, and surfaces already covered with polymer films experience rupture due to volume expansion, exposing the alloy to impurity gases and leading to a decrease in the composite material's resistance to poisoning. Furthermore, no oxide / carbide formation was observed on the exposed fresh alloy surface, indicating that at room temperature, trace amounts of impurity gases can only be adsorbed on the alloy surface without causing chemical poisoning. As the hydrogen adsorption / desorption cycle continues, it can be observed that the surface polymer film of the PMMA+PP modified composite hydrogen storage material ruptures less than that of the PMMA-modified composite hydrogen storage material, reflecting its superior resistance to poisoning. This is because PP (polypropylene) has higher strength, resulting in a relatively stronger polymer film on the surface of the composite hydrogen storage material containing 2.5 wt.% PMMA and 2.5 wt.% PP, thus exhibiting a lower degree of degradation in its resistance to poisoning compared to the PMMA-modified composite material.

[0052] Example 3: To address the issue of the degradation of the anti-poisoning performance of polymer-modified metal hydride hydrogen storage materials during hydrogen absorption and desorption cycles, and in response to the problem of the degradation of the anti-poisoning performance of polymer-modified metal hydride hydrogen storage materials during hydrogen absorption and desorption cycles, the 2.5 wt.% PMMA+2.5 wt.% PP ball-milled Ti from Example 2 was subjected to 10 hydrogen absorption and desorption cycles in a hydrogen atmosphere containing trace impurities. 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2The hydrogen storage material was placed in a reactor and heated to 393 K (120 °C). It was then purged at a rate of 60 mL / min for 1 h to ensure complete desorption of impurity gases adsorbed on the exposed, powdered alloy surface. Next, it was held under a vacuum below 0.01 Pa for 1 h to achieve thermal repair. SEM images of the repaired modified hydrogen storage material are shown below. Figure 8 As shown, the alloy surface is re-covered with relatively complete polymer particles, and the polymer particles are finer. Since the heat distortion temperature of PMMA is about 368~378 K (95~105℃) and that of PP is about 383 K (110℃), heating to 393 K can effectively soften the polymer film on the alloy surface and allow it to redistribute. As the temperature gradually decreases to room temperature, it recrystallizes and hardens, forming a polymer film with a higher coverage than before the heat repair.

[0053] To investigate the impact of regeneration treatment on the anti-poisoning performance of modified metal hydride hydrogen storage materials, the hydrogen absorption kinetics of the regenerated PMMA+PP modified composite hydrogen storage material in impurity gases were tested. Figure 9 As shown in the figure, compared to the hydrogen absorption capacity of the composite hydrogen storage material in impurity gas after 10 hydrogen absorption / desorption cycles, regeneration treatment effectively improves its anti-poisoning performance. In H2 + 500 ppm CO impurity gas, the regenerated hydrogen storage material retains 74% of its theoretical maximum hydrogen absorption capacity, significantly higher than the 25% of the pure alloy and 58% before regeneration treatment, only slightly lower than the 80% absorbed during the first hydrogen absorption in impurity gas after activation. In H2 + 500 ppm CO2 impurity gas, the hydrogen absorption capacity of the regenerated hydrogen storage material is 98% of the theoretical maximum value, slightly lower than the 99% absorbed during the first hydrogen absorption in impurity gas after activation, but higher than the 93% before regeneration treatment and the 86% of the pure alloy. Thanks to the high-coverage polymer film reformed on the alloy surface during the heat treatment process of the modified metal hydride hydrogen storage material, its anti-poisoning performance is improved compared to before treatment.

[0054] Furthermore, it should be understood that after reading the above description of the present invention, those skilled in the art can make various alterations or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims.

Claims

1. A method for regenerating a pulverized polymer-hydrogen storage alloy composite material poisoned by impurity gases, characterized in that, The impurity gas poisoning pulverized polymer-hydrogen storage alloy composite material includes a hydrogen storage alloy and a polymer that partially coats the hydrogen storage alloy, and the exposed surface of the hydrogen storage alloy that is not coated by the polymer is partially or completely adsorbed and / or covered by the impurity gas. The regeneration method includes the following steps: (1) The powdered polymer-hydrogen storage alloy composite material poisoned by the impurity gas is purged with flowing hydrogen at 50~200℃ to desorb the impurity gas and obtain intermediate repair material; (2) The intermediate repair material is dynamically vacuum heated to soften and thermally deform the polymer and then spread and flow again, thereby increasing the coating rate of the polymer on the hydrogen storage alloy, completing the secondary coating, and then cooling to obtain the regenerated polymer-hydrogen storage alloy composite material.

2. The regeneration method according to claim 1, characterized in that, The impurity gas includes one or more of CO, CO2, N2, and Ar.

3. The regeneration method according to claim 1, characterized in that, The poisoning environment of the powdered polymer-hydrogen storage alloy composite material poisoned by impurity gases is a hydrogen atmosphere with an impurity gas content not exceeding 500 ppmv.

4. The regeneration method according to claim 1, characterized in that, The polymer includes one or more of polymethyl methacrylate, polyethylene, polypropylene, and polycaprolactone.

5. The regeneration method according to claim 4, characterized in that, The polymer includes polymethyl methacrylate and polypropylene; The mass ratio of the polymethyl methacrylate to the polypropylene is 10:1 to 100, and more preferably 1:

1.

6. The regeneration method according to claim 1, characterized in that, The hydrogen storage alloy includes at least one of AB5 type hydrogen storage alloy and AB2 type hydrogen storage alloy, further includes one or more of LaNi5 type hydrogen storage alloy, TiMn2 type hydrogen storage alloy, and TiCr2 type hydrogen storage alloy, and even further includes Ti 0.9 Zr 0.2 Cr 0.7 Mn 0.7 Fe 0.4 V 0.2 Hydrogen storage alloy.

7. The regeneration method according to claim 1, characterized in that, The mass ratio of the polymer to the hydrogen storage alloy is 1~50:100, and more specifically 5~20:

100.

8. The regeneration method according to claim 1, characterized in that, The impurity gas poisoned pulverized polymer-hydrogen storage alloy composite material, wherein the polymer is coated onto the surface of the hydrogen storage alloy by ball milling; The ball milling is carried out under an inert atmosphere; the inert atmosphere includes a nitrogen atmosphere and / or a rare gas atmosphere; the rare gas includes at least one of argon and helium; The ball mill is a planetary ball mill or a vibrating ball mill; The ball mill jar used in the ball mill is made of one or more of the following materials: stainless steel, agate, and polytetrafluoroethylene. The ball mill rotates at a speed of 100~600 rpm; The ball milling time is 1~100 h; The ball-to-material ratio in the ball milling process is 10~100:

1.

9. The regeneration method according to claim 1, characterized in that, In step (1): The flow rate of the flowing hydrogen purging is 10~200 mL / min; The purging time with flowing hydrogen is 0.5 to 12 hours.

10. The regeneration method according to claim 1, characterized in that, In step (2): The vacuum heating temperature is greater than or equal to the softening heat deformation temperature of the polymer, for example, 50~200℃; The vacuum degree of the vacuum heating is below 0.01 Pa; The dynamic vacuum heating time is 0.5~12 h.

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