A method for producing a titanium-based hydrogen storage alloy block and use thereof

Abstract

The present application relates to a kind of preparation method of titanium hydrogen storage alloy block and its use.The titanium hydrogen storage alloy block prepared by the preparation method of the present application can directly occur hydrogen absorption and desorption reaction at room temperature in the form of complete block after peeling from outer titanium shell without secondary treatment;It effectively avoids that the shell is too dense and it is difficult to peel the titanium hydrogen storage alloy block;Titanium waste is used as raw material, and the cost of raw material is maintained at a low level.In addition, the preparation process of the present application simplifies the traditional smelting crushing or large plastic deformation process, and only one step sintering can obtain the titanium hydrogen storage alloy block that can be directly used, and the addition of high-cost rare earth elements is avoided, and the advantages of short process and low cost are considered.

Description

Technical Field

[0001] This invention relates to the field of hydrogen storage alloy technology, specifically to a method for preparing a titanium-based hydrogen storage alloy block and its applications. Background Technology

[0002] Against the backdrop of an escalating energy crisis, hydrogen's high calorific value makes it an ideal energy carrier to replace fossil fuels. Hydrogen storage alloys, as a safe and efficient method of hydrogen storage, hold promise for applications in fields such as hydrogen-powered vehicles. Currently, practically viable hydrogen storage materials include titanium-based, magnesium-based, rare-earth-based, and vanadium-based alloys. Among these, titanium-based hydrogen storage alloys, with their abundant raw material reserves and mild hydrogen absorption / desorption conditions, have become one of the most promising hydrogen storage alloys.

[0003] Because titanium alloys have a high affinity for oxygen, the oxide layer on their surface hinders the hydrogen absorption process. In laboratory studies, arc melting is the most widely used method for synthesizing gram-scale titanium-based hydrogen storage alloys. However, the prepared hydrogen storage alloys are costly and often suffer from problems such as component segregation, requiring lengthy homogenization treatment. Therefore, methods such as component optimization, surface modification, and large plastic deformation are used to improve hydrogen absorption activation performance. However, defects such as strain and amorphous material introduced by plastic deformation can cause significant hydrogen absorption / desorption hysteresis and poor cycle stability. Powder metallurgy, as a near-net-shape metal forming technology, can effectively address the segregation of high-melting-point elements during melting by optimizing the sintering process. Furthermore, the formation of sintering necks during powder consolidation creates a small number of pores, which helps improve the mass and heat transfer performance during hydrogen absorption / desorption. However, the oxygen content of hydrogen storage alloys prepared using this method is usually higher than the industrial requirements for the oxygen content in pure titanium. Summary of the Invention

[0004] To address the current technical challenges facing the industry, this invention develops a method for preparing titanium-based hydrogen storage alloy blocks and their applications. The titanium-based hydrogen storage alloy blocks prepared by this method, after being peeled from the outer titanium shell, have no oxide layer on their surface that hinders the hydrogen absorption process. Therefore, no secondary processing is required, and the intact block can directly undergo hydrogen absorption and desorption reactions at room temperature. Furthermore, the titanium-based hydrogen storage alloy blocks prepared by this method exhibit low oxygen content and suitable porosity. The uniform coating of the titanium-based hydrogen storage alloy billet with a titanium-based cladding material containing FeCl3 achieves oxygen removal and isolation, greatly reducing the oxidation risk during sintering and effectively preventing the outer shell from being too dense to easily peel off the titanium-based hydrogen storage alloy block. Using titanium waste as raw material and titanium shavings or powder waste as the cladding material to form the titanium shell maintains a low raw material cost. Furthermore, the preparation process of this invention simplifies the traditional processes of smelting, crushing, or large plastic deformation, and can obtain directly usable titanium-based hydrogen storage alloy blocks in just one sintering step. It also avoids the addition of high-cost rare earth elements, combining the advantages of short process and low cost, and provides an efficient, reliable, and low-cost production process for the large-scale application of titanium-based hydrogen storage alloys.

[0005] On one hand, the present invention provides a method for preparing a titanium-based hydrogen storage alloy block, comprising the following steps: Step 1): According to the raw material ratio of the titanium-based hydrogen storage alloy block, the raw material powder is mixed in an inert atmosphere to obtain a mixed powder. The oxygen content of the mixed powder is greater than 0.35 wt.% and less than 0.65 wt.%. The titanium raw material in the raw material powder is titanium raw material containing titanium powder waste, and the mass percentage of titanium powder waste in the titanium raw material is 25~75 wt.%, and the titanium raw material is doped with 0.5 wt.% and less than 2.0 wt.% FeCl3; Step 2): The mixed powder is pre-pressed in an inert atmosphere to obtain a titanium-based hydrogen storage alloy billet; Step 3): The titanium-based hydrogen storage alloy billet is placed in a sintering furnace, and a coating material is uniformly spread on the surface of the billet. The coating material has a thickness of 3-15 mm and a looseness of 1.0-2.0 g / cm³ per unit volume. 3 ; The coating material is titanium scrap or titanium powder waste doped with FeCl3, wherein the FeCl3 doping content in the coating material is greater than or equal to 1.0 wt.% and less than 4.0 wt.%. Step 4): The titanium-based hydrogen storage alloy billet with the coating material is sintered under high-purity argon protection at a temperature of 850~1250 ℃ for 2~5 h to obtain a titanium shell-titanium-based hydrogen storage alloy block with a titanium shell coating; the titanium shell is peeled off to obtain the titanium-based hydrogen storage alloy block.

[0006] In this invention, the thickness of the coating material on the surface of the titanium-based hydrogen storage alloy billet is 3~15 mm, and the coating thickness varies depending on the location of the coating on the block surface.

[0007] In this invention, the obtained titanium-based hydrogen storage alloy block is a complete, unbroken block. Protected by an outer titanium shell, its surface exhibits a metallic luster and is free of an oxide layer that hinders the hydrogen absorption process. The complete, unbroken shape of the titanium-based hydrogen storage alloy block means that the shape of the sintered alloy block is consistent with the shape of the powder compact before sintering. The samples used for performance testing are complete blocks directly peeled from the outer titanium shell, eliminating the need for secondary processing such as crushing, thus simplifying the process.

[0008] In this invention, titanium powder waste is used as the source of titanium in the raw materials, and titanium shavings or titanium powder waste is used as the coating material to form the titanium shell, further reducing material costs. By utilizing the deoxygenating effect of FeCl3 and the protective effect of the outer titanium shell on the internal titanium-based hydrogen storage alloy block, the oxygen content in the sintered titanium-based hydrogen storage alloy block is controlled at a low level.

[0009] In this invention, the doping amount of FeCl3 in the titanium raw material and coating material is controlled within the range described herein. Combined with the processing technology, the dual functions of FeCl3 in deoxygenation and pore formation can be fully utilized. Thermodynamically, it spontaneously reacts with titanium oxides to generate oxygen-containing products, which are then removed from the pores. After sintering, a porous titanium shell with low oxygen content is obtained. This effectively protects the internal alloy block while the porous structure of the shell facilitates the peeling off of the internal alloy block.

[0010] In this invention, for the directly usable titanium-based hydrogen storage alloy block inside, an excessively high oxygen content in the mixture negatively impacts hydrogen storage performance. However, reducing the oxygen content of the mixture is often limited by cost and specific preparation processes. The oxygen content of the mixture, greater than 0.35 wt.% and less than 0.65 wt.%, represents the suitable oxygen content range achievable under the conditions of titanium shell protection and the use of inexpensive titanium powder, as described in this invention.

[0011] In this invention, the sintering temperature is specifically selected based on the phase diagram of the titanium alloy. If the sintering time is too long, the risk of oxidation will be greatly increased; conversely, if the sintering time is too short, it will be difficult to ensure that the alloy is sufficiently homogeneous.

[0012] In this invention, during the sintering process, the titanium-based hydrogen storage alloy block is coated with a coating material. During the sintering process, the outer coating material undergoes particle consolidation and elemental diffusion. At the interface between the outer titanium shell and the inner titanium-based hydrogen storage alloy block, there is a possibility of component segregation. The segregation of the hydrophilic coating material on the surface of the titanium-based hydrogen storage alloy block is conducive to the dissociation of hydrogen molecules, which makes the titanium-based hydrogen storage alloy block of this invention have good hydrogen absorption kinetics. At the same time, the titanium-based hydrogen storage alloy block has good cycle stability.

[0013] Furthermore, in the preparation method of the titanium-based hydrogen storage alloy block of the present invention, the titanium powder waste is metal powder, and the particle size of the metal powder is 50~200 mesh. The titanium powder waste contains O < 0.45 wt.%, Fe < 0.3 wt.%, Si < 0.1 wt.%, Ni < 0.1 wt.%, Cu < 0.1 wt.%, Cr < 0.1 wt.%, with the balance being Ti. The titanium shavings are strip-shaped sheets with a width of about 5 mm. The titanium shavings contain O < 0.4 wt.%, Cr < 0.1 wt.%, Fe < 0.5 wt.%, Al < 0.65 wt.%, V < 0.1 wt.%, and the balance is Ti.

[0014] In this invention, the titanium scrap or titanium powder waste is inexpensive titanium, which further reduces costs. If metal particles with too small a powder size are used, due to their higher surface energy, a denser titanium shell will be obtained after sintering, making it difficult to peel off the internal titanium-based hydrogen storage alloy block and hindering the discharge of oxygen-containing products. By using titanium scrap or titanium powder waste as the outer titanium shell component, controlling the raw material size, and combining this with the looseness and thickness of the coating material, the problem of the titanium-based hydrogen storage alloy block being difficult to peel off from the shell can be cleverly avoided.

[0015] In this invention, the inexpensive titanium coating eliminates the need for pre-pressing and other treatment processes on the outer titanium shell. On the one hand, this shortens the preparation process. On the other hand, by utilizing the consolidation effect of the sintering process, combined with the pore-forming effect of ferric chloride, a loose outer titanium shell can be obtained during the sintering process, which facilitates the removal of the hydrogen storage alloy from it.

[0016] Furthermore, in the preparation method of the titanium-based hydrogen storage alloy block of the present invention, in step 4), the remaining amount of FeCl3 in the titanium shell is 5% to 30% of the initial content.

[0017] Furthermore, in the preparation method of the titanium-based hydrogen storage alloy block of the present invention, in step 4), the thickness of the titanium shell is 1~10 mm; the titanium shell has a porous structure.

[0018] Furthermore, in the preparation method of the titanium-based hydrogen storage alloy block of the present invention, the oxygen content of the titanium-based hydrogen storage alloy block is greater than 0.2 wt.% and less than 0.65 wt.%.

[0019] Furthermore, in the preparation method of the titanium-based hydrogen storage alloy block of the present invention, the surface of the titanium-based hydrogen storage alloy block exhibits a metallic luster, and the titanium-based hydrogen storage alloy block does not contain rare earth elements lanthanum, cerium, and yttrium.

[0020] In this invention, the presence of a fresh, metallic-lustered surface on the titanium-based hydrogen storage alloy block is due, in part, to the protective effect of the outer titanium shell, which allows the sintered block to retain its metallic luster due to lack of oxidation. This fresh surface indicates that the oxygen content on the surface of the block material remains at a low level, a prerequisite for good hydrogen absorption kinetics. Furthermore, because a metal cladding material is applied to the titanium-based hydrogen storage alloy blank, the outer metal cladding material undergoes particle consolidation and elemental diffusion during sintering. This results in compositional segregation at the interface between the outer titanium shell and the inner titanium-based hydrogen storage alloy block. The segregation of the hydrophilic metal on the block surface facilitates the dissociation of hydrogen molecules.

[0021] Furthermore, in the preparation method of the titanium-based hydrogen storage alloy block of the present invention, the titanium-based hydrogen storage alloy block is any one of Ti-Fe, Ti-Mn, Ti-Cr and Ti-Co systems.

[0022] Furthermore, in the preparation method of the titanium-based hydrogen storage alloy block of the present invention, the Ti-Fe system is TiFe. 0.9 Zr 0.1 TiFe 0.8 Ni 0.2 TiFe 0.9 Al 0.1 Any one of them; The Ti-Mn system is Ti 0.9 Zr 0.2 Mn 1.8 V 0.2 Ti 1.2 MnCr, Ti 0.8 Zr 1.2 Mn 1.5 Cu 0.5 Any one of them; The Ti-Cr system is TiCr 1.8 Ti 1.2 Cr 1.2 Mn 0.8 Ti 0.8 Zr 0.2 CrMn 0.8 Co 0.2 Any one of them; The Ti-Co system is TiCo, TiCo 0.75 Ni 0.25 Ti 0.9 V 0.1 Any of Co.

[0023] Furthermore, in the preparation method of the titanium-based hydrogen storage alloy block of the present invention, in step 1), the mixing speed is 20~100 r / min and the mixing time is 30~180 min; in step 2), the pre-pressing pressure is 2~10 MPa and the holding time is 3~20 min.

[0024] In this invention, the selection of the pre-pressing pressure range should, on the basis of ensuring that the powder can be formed into a green body, improve the contact between metal powders as much as possible and enhance the bonding force between raw material powders. However, excessive pre-pressing pressure is not conducive to the removal of pore-forming agents and gaseous products, reduces the porosity of pores, and affects the mass and heat transfer performance of the material during hydrogen absorption and desorption. Therefore, the process parameters of pressing molding also need to be matched with the pore-forming agent, alloy composition, etc.

[0025] On the other hand, the present invention provides an application of a titanium-based hydrogen storage alloy block, wherein the titanium-based hydrogen storage alloy block is prepared by the preparation method of the titanium-based hydrogen storage alloy block described in any of the above claims, and the titanium-based hydrogen storage alloy block does not require secondary processing and crushing, and directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0026] The beneficial effects of this invention are: The ready-to-use titanium-based hydrogen storage alloy block of the present invention is prepared by sintering a titanium shavings or titanium powder waste containing FeCl3 onto the outer surface of the alloy powder compact. Combining the deoxidizing effect of FeCl3 and the oxygen-barrier effect of the titanium shell, the oxidation risk of the material during sintering is greatly reduced. The oxygen content in the prepared titanium-based hydrogen storage alloy block is less than 0.65 wt.%, while maintaining low raw material costs. Low oxygen content is a key condition for ensuring good hydrogen storage performance of the alloy. The deoxidizing effect of FeCl3 in the outer titanium shell effectively prevents the outer shell from being too dense to peel off the titanium-based hydrogen storage alloy block. The alloy block is protected by the outer titanium shell, exhibits a metallic luster, and has no oxide layer that hinders the hydrogen absorption process. The ready-to-use titanium-based hydrogen storage alloy block obtained by one-step sintering is a complete titanium-based hydrogen storage alloy block that does not require breakage.

[0027] On the other hand, the preparation method of this invention can effectively solve the problems of high cost and component segregation in traditional smelting methods. Furthermore, through the synergistic design of the pre-compression pressure (2~10 MPa) of the mixed powder and ferric chloride (content 0.5~2.0 wt.%), a low-oxygen titanium-based hydrogen storage alloy block material with suitable porosity is prepared. This process simplifies traditional smelting, crushing, or large plastic deformation processes, avoids the addition of high-cost rare earth elements, and combines the advantages of short process and low cost, providing an efficient and reliable technical route for the large-scale application of titanium-based hydrogen storage alloys. Attached Figure Description

[0028] Figure 1 This is a complete external view of the titanium-based hydrogen storage alloy block of Embodiment 1 of the present invention; Figure 2 This is a test diagram of the hydrogen absorption and desorption cycle performance of the titanium-based hydrogen storage alloy block in Embodiment 1 of the present invention. Detailed Implementation

[0029] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments are now described in detail with reference to the accompanying drawings. The described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the detailed embodiments, conventional conditions or conditions provided by the manufacturer shall apply.

[0030] In the following description, when referring to the accompanying drawings, the same numbers in different drawings denote the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure.

[0031] The present invention discloses a method for preparing a titanium-based hydrogen storage alloy block, comprising the following steps: Step 1): According to the raw material ratio of the titanium-based hydrogen storage alloy block, the raw material powder is mixed in an inert atmosphere to obtain a mixed powder. The oxygen content of the mixed powder is greater than 0.35 wt.% and less than 0.65 wt.%. The titanium raw material in the above-mentioned raw material powder is titanium raw material containing titanium powder waste. The mass percentage of titanium powder waste in the above-mentioned titanium raw material is 25~75 wt.%, and the above-mentioned titanium raw material is doped with 0.5 wt.% and less than 2.0 wt.% FeCl3. Step 2): The above mixed powder is pre-pressed in an inert atmosphere to obtain a titanium-based hydrogen storage alloy billet; Step 3): The titanium-based hydrogen storage alloy billet is placed in a sintering furnace, and a coating material is uniformly spread on the surface of the billet. The thickness of the coating material is 3-15 mm, and the looseness of the coating is 1.0-2.0 g / cm³. 3 ; The aforementioned coating material is titanium scrap or titanium powder waste doped with FeCl3, wherein the FeCl3 doping content in the coating material is greater than or equal to 1.0 wt.% and less than 4.0 wt.%. Step 4): The titanium-based hydrogen storage alloy billet with the coating material is sintered under high-purity argon protection at a temperature of 850~1250 ℃ for 2~5 h to obtain a titanium shell-titanium-based hydrogen storage alloy block with a titanium shell coating; the titanium shell is peeled off to obtain the titanium-based hydrogen storage alloy block.

[0032] In some embodiments, the titanium powder waste is metal powder with a particle size of 50-200 mesh, and the titanium powder waste contains O < 0.45 wt.%, Fe < 0.3 wt.%, Si < 0.1 wt.%, Ni < 0.1 wt.%, Cu < 0.1 wt.%, Cr < 0.1 wt.%, with the balance being Ti; The titanium shavings are strip-shaped sheets with a width of about 5 mm. The titanium shavings contain O < 0.4 wt.%, Cr < 0.1 wt.%, Fe < 0.5 wt.%, Al < 0.65 wt.%, V < 0.1 wt.%, and the balance is Ti.

[0033] In some embodiments, in step 4) above, the remaining amount of FeCl3 in the titanium shell is 5% to 30% of the initial content.

[0034] In some embodiments, in step 4) above, the thickness of the titanium shell is 1 to 10 mm, and the titanium shell has a porous structure.

[0035] In some embodiments, the oxygen content of the above-mentioned titanium-based hydrogen storage alloy block is greater than 0.2 wt.% and less than 0.65 wt.%.

[0036] In some embodiments, the surface of the titanium-based hydrogen storage alloy block exhibits a metallic luster, and the titanium-based hydrogen storage alloy block does not contain the rare earth elements lanthanum, cerium, and yttrium.

[0037] In some embodiments, the aforementioned titanium-based hydrogen storage alloy block is any one of the Ti-Fe, Ti-Mn, Ti-Cr, and Ti-Co systems.

[0038] In some embodiments, the above-mentioned Ti-Fe system is TiFe. 0.9 Mn0.1 TiFe 0.8 Ni 0.2 TiFe 0.9 Al 0.1 Any one of them; In some embodiments, the above-mentioned Ti-Mn system is Ti 0.9 Zr 0.2 Mn 1.8 V 0.2 Ti 1.2 MnCr, Ti 0.8 Zr 1.2 Mn 1.5 Cu 0.5 Any one of them; In some embodiments, the above-mentioned Ti-Cr system is TiCr 1.8 Ti 1.2 Cr 1.2 Mn 0.8 Ti 0.8 Zr 0.2 CrMn 0.8 Co 0.2 Any one of them; In some embodiments, the above-mentioned Ti-Co system is TiCo or TiCo. 0.75 Ni 0.25 Ti 0.9 V 0.1 Any of Co.

[0039] In some embodiments, in step 1) above, the mixing speed is 20~100 r / min and the mixing time is 30~180 min; in step 2) above, the pre-pressing pressure is 2~10 MPa and the holding time is 3~20 min. Specific Implementation Method Two: On the other hand, the present invention provides an application of a titanium-based hydrogen storage alloy block, wherein the titanium-based hydrogen storage alloy block is a titanium-based hydrogen storage alloy block prepared by any of the above-mentioned methods in Embodiment 1. The titanium-based hydrogen storage alloy block does not require secondary processing and crushing, and directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0041] The present invention will be further described in detail below with reference to specific embodiments.

[0042] Example 1: This invention discloses a method for preparing a titanium-based hydrogen storage alloy block, wherein the titanium-based hydrogen storage alloy block is Ti 0.8 Zr 1.2 Mn 1.5 Cu 0.5 The preparation method includes the following steps: Step 1): According to Ti 0.8 Zr 1.2 Mn 1.5 Cu 0.5 The raw material ratio was determined by mixing 3.83 g of titanium raw material, 10.95 g of Zr, 8.24 g of Mn and 3.18 g of Cu raw material powder in an inert atmosphere to obtain a mixed powder with an oxygen content of 0.39 wt.%. The mixing speed was 30 r / min and the mixing time was 180 min.

[0043] The titanium raw material in the raw material powder is titanium raw material containing titanium powder waste, and the mass percentage of titanium powder waste in the titanium raw material is 25 wt.%, and the titanium raw material is doped with 0.5 wt.% FeCl3; Step 2): The mixed powder is pre-pressed in an inert atmosphere to obtain a titanium-based hydrogen storage alloy billet. The pre-pressing pressure is 10 MPa, and the holding time is 10 min.

[0044] Step 3): The titanium-based hydrogen storage alloy billet is placed in the sintering furnace, and a coating material is evenly spread on the surface of the billet. Considering the different positions of the coating material on the surface of the block, the minimum coating thickness is not less than 3 mm, and the looseness of the coating is: the mass of the coating material per unit volume is 2.0 g / cm³. 3 ; The coating material is titanium powder waste doped with FeCl3, and the FeCl3 doping content in the coating material is 1.0 wt.%. Step 4): The titanium-based hydrogen storage alloy billet coated with the cladding material is sintered under high-purity argon protection at a temperature of 850–1250 °C for 2–5 h to obtain a titanium-shell-titanium-based hydrogen storage alloy block with a titanium shell coating. The titanium shell is then removed to obtain the titanium-based hydrogen storage alloy block. The remaining FeCl3 content in the titanium shell is 5%–30% of the initial content. The titanium shell has a porous structure with a porosity of 20%–25%.

[0045] The titanium powder waste is a metal powder with a particle size of 50-200 mesh. The titanium powder waste contains O < 0.45 wt.%, Fe < 0.3 wt.%, Si < 0.1 wt.%, Ni < 0.1 wt.%, Cu < 0.1 wt.%, Cr < 0.1 wt.%, and the balance is Ti. The titanium-based hydrogen storage alloy block prepared in Example 1 has no oxide layer on its surface that hinders the hydrogen absorption process, and requires no secondary processing or crushing; it directly undergoes hydrogen absorption and desorption reactions at room temperature in its complete block form. Figure 1 As shown, after the sintered titanium-based hydrogen storage alloy block is peeled off from the outer titanium shell, it exhibits a metallic luster because it has not been significantly oxidized, and the oxygen content on the surface of the titanium-based hydrogen storage alloy block material remains at a low level.

[0046] The oxygen content, initial hydrogen absorption incubation period (min), hydrogen absorption capacity of the titanium-based hydrogen storage alloy block in Example 1, the hydrogen absorption capacity after 10 cycles, and the room-temperature hydrogen storage capacity decay rate are shown in Table 1. The hydrogen absorption capacity of the titanium-based hydrogen storage alloy block in Example 1 after 10 cycles is shown in Table 1. Figure 2 As shown.

[0047] Example 2: The only difference between Example 2 and Example 1 is that the titanium-based hydrogen storage alloy block is TiFe. 0.8 Ni 0.2 In step 1), according to TiFe 0.8 Ni 0.2 The raw materials were weighed according to the specified ratio, and the oxygen content of the mixed powder was 0.48 wt.%.

[0048] In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.6 g / cm³. 3 The FeCl3 doping content in the coating material is 2.0 wt.%.

[0049] In step 4), the titanium shell has a porous structure with a porosity of 30-35%.

[0050] The titanium-based hydrogen storage alloy block prepared in Example 2 has no oxide layer on its surface that hinders the hydrogen absorption process, and it does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0051] Example 3: The only difference between Example 3 and Example 1 is that the titanium-based hydrogen storage alloy block is TiFe. 0.9 Al 0.1 In step 1), according to TiFe 0.9 Al 0.1 The raw materials were weighed according to the specified ratio, and the oxygen content of the mixed powder was 0.48 wt.%.

[0052] In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.2 g / cm³. 3 The FeCl3 doping content in the coating material is 4.0 wt.%.

[0053] In step 4), the titanium shell has a porous structure with a porosity of 45-55%.

[0054] The titanium-based hydrogen storage alloy block prepared in Example 3 has no oxide layer on its surface that hinders the hydrogen absorption process, and it does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0055] Example 4: The only difference between Example 4 and Example 1 is that the titanium-based hydrogen storage alloy block is Ti. 0.9 Zr 0.2 Mn 1.8 V 0.2 In step 1), according to Ti 0.9 Zr 0.2 Mn 1.8 V 0.2 The raw materials were weighed according to the specified ratio. The oxygen content of the mixed powder was 0.39 wt.%, and the titanium raw material was doped with 1.0 wt.% FeCl3.

[0056] In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.4 g / cm³. 3 The FeCl3 doping content in the coating material is 3.0 wt.%.

[0057] In step 4), the titanium shell has a porous structure with a porosity of 40-45%.

[0058] The titanium-based hydrogen storage alloy block prepared in Example 4 has no oxide layer on its surface that hinders the hydrogen absorption process, and it does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0059] Example 5: The only difference between Example 5 and Example 1 is that the titanium-based hydrogen storage alloy block is Ti. 1.2 In step 1) of MnCr, according to Ti 1.2 The raw materials were weighed according to the MnCr ratio. The mass percentage of titanium powder waste in the titanium raw material was 50 wt.%, the oxygen content of the mixed powder was 0.51 wt.%, and the titanium raw material was doped with 1.0 wt.% FeCl3. In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.6 g / cm³. 3 The FeCl3 doping content in the coating material is 2.0 wt.%. In step 4), the titanium shell has a porous structure with a porosity of 30-35%.

[0060] The titanium-based hydrogen storage alloy block prepared in Example 5 has no oxide layer on its surface that hinders the hydrogen absorption process, and it does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0061] Example 6: The only difference between Example 6 and Example 1 is that the titanium-based hydrogen storage alloy block is TiFe. 0.9 Mn 0.1 In step 1), according to TiFe 0.9 Mn 0.1The raw materials were weighed according to the specified ratio. The titanium powder waste accounted for 50 wt.% of the titanium raw materials, the oxygen content of the mixed powder was 0.52 wt.%, and 1.0 wt.% FeCl3 was doped into the titanium raw materials. In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.2 g / cm³. 3 The coating material contains 4.0 wt.% FeCl3. In step 4), the titanium shell has a porous structure with a porosity of 45-55%.

[0062] The titanium-based hydrogen storage alloy block prepared in Example 6 has no oxide layer on its surface that hinders the hydrogen absorption process, and it does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0063] Example 7: The only difference between Example 7 and Example 1 is that the titanium-based hydrogen storage alloy block is TiCr. 1.8 In step 1), according to TiCr 1.8 The raw materials were weighed according to the specified ratio. The titanium powder waste accounted for 50 wt.% of the titanium raw materials, the oxygen content of the mixed powder was 0.47 wt.%, and 1.5 wt.% FeCl3 was doped into the titanium raw materials. In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.2 g / cm³. 3 The coating material contains 4.0 wt.% FeCl3. In step 4), the titanium shell has a porous structure with a porosity of 45-55%.

[0064] The titanium-based hydrogen storage alloy block prepared in Example 7 has no oxide layer on its surface that hinders the hydrogen absorption process, and it does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0065] Example 8: The only difference between Example 8 and Example 1 is that the titanium-based hydrogen storage alloy block is Ti. 1.2 Cr 1.2 Mn 0.8 In step 1), according to Ti 1.2 Cr 1.2 Mn 0.8 The raw materials were weighed according to the specified ratio. The oxygen content of the mixed powder was 0.57 wt.%, the mass ratio of titanium powder waste in the titanium raw material was 75 wt.%, and the titanium raw material was doped with 1.5 wt.% FeCl3. In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.8 g / cm³. 3The coating material contains 1.0 wt.% FeCl3; In step 4), the titanium shell has a porous structure with a porosity of 20% to 25%.

[0066] The titanium-based hydrogen storage alloy block prepared in Example 8 has no oxide layer on its surface that hinders the hydrogen absorption process, and it does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0067] Example 9: The only difference between Example 9 and Example 1 is that the titanium-based hydrogen storage alloy block is Ti. 0.8 Zr 0.2 CrMn 0.8 Co 0.2 In step 1), according to Ti 0.8 Zr 0.2 CrMn 0.8 Co 0.2 The raw materials were weighed according to the specified ratio. The titanium powder waste accounted for 75 wt.% of the titanium raw materials, the oxygen content of the mixed powder was 0.55 wt.%, and 1.5 wt.% FeCl3 was doped into the titanium raw materials. In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.4 g / cm³. 3 The coating material contains 3.0 wt.% FeCl3; In step 4), the titanium shell has a porous structure with a porosity of 40% to 45%.

[0068] The titanium-based hydrogen storage alloy block prepared in Example 9 has no oxide layer on its surface that hinders the hydrogen absorption process, and it does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0069] Example 10: The only difference between Example 10 and Example 1 is that the titanium-based hydrogen storage alloy block is TiCo. In step 1), the raw materials are weighed according to the proportion of TiCo. The mass percentage of titanium powder waste in the titanium raw material is 75 wt.%, the oxygen content of the mixed powder is 0.65 wt.%, and 1.5 wt.% of FeCl3 is doped in the titanium raw material. In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.2 g / cm³. 3 The coating material contains 4.0 wt.% FeCl3. In step 4), the titanium shell has a porous structure with a porosity of 45-55%.

[0070] The titanium-based hydrogen storage alloy block prepared in Example 10 does not require secondary processing or crushing; it directly undergoes hydrogen absorption and desorption reactions at room temperature in its complete block form.

[0071] Example 11: The only difference between Example 11 and Example 1 is that the titanium-based hydrogen storage alloy block is TiCo. 0.75 Ni 0.25 In step 1), according to TiCo 0.75 Ni 0.25 The raw materials were weighed according to the specified ratio. The titanium powder waste accounted for 75 wt.% of the titanium raw materials, the oxygen content of the mixed powder was 0.59 wt.%, and 2.0 wt.% FeCl3 was doped into the titanium raw materials. In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.8 g / cm³. 3 The coating material contains 1.0 wt.% FeCl3; In step 4), the titanium shell has a porous structure with a porosity of 20-25%.

[0072] The titanium-based hydrogen storage alloy block prepared in Example 11 does not require secondary processing or crushing; it directly undergoes hydrogen absorption and desorption reactions at room temperature in its complete block form.

[0073] Example 12: The only difference between Example 12 and Example 1 is that the titanium-based hydrogen storage alloy block is Ti. 0.9 V 0.1 In step 1), according to Ti 0.9 V 0.1 The raw materials were weighed according to the Co ratio. The titanium raw materials contained 75 wt.% titanium powder waste, 0.60 wt.% oxygen content of mixed powder, and 2.0 wt.% FeCl3 doped into the titanium raw materials. In step 3), the looseness of the covering material is: the mass of the covering material per unit volume is 1.2 g / cm³. 3 The coating material contains 4.0 wt.% FeCl3. In step 4), the titanium shell has a porous structure with a porosity of 45-55%.

[0074] The titanium-based hydrogen storage alloy block prepared in Example 12 has no oxide layer on its surface that hinders the hydrogen absorption process, and does not require secondary processing or crushing. It directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

[0075] Comparative Example 1: The only difference between Comparative Example 1 and Example 1 is that, in step 1), the FeCl3 doping in the titanium raw material is 0 wt.%.

[0076] Comparative Example 2: The only difference between Comparative Example 2 and Example 2 is that, in step 1), the titanium powder waste in the titanium powder raw material accounts for 100 wt.% of the mixed powder.

[0077] Comparative Example 3: The only difference between Comparative Example 3 and Example 7 is that, in step 3), the spread density is: the mass of the covering material per unit volume is 3.0 g / cm³. 3 The mass percentage of FeCl3 in the coating material is 0 wt.%. In step 4), the titanium shell has a porous structure with a porosity of 5-20%.

[0078] Comparative Example 4: The only difference between Comparative Example 4 and Example 10 is that, in step 3), the spread density is: the mass of the covering material per unit volume is 0.8 g / cm³. 3 The mass percentage of FeCl3 in the coating material is 5.0 wt.%. In step 4), the titanium shell has a porous structure with a porosity of 45-65%.

[0079] The oxygen content, initial hydrogen absorption incubation period (min), hydrogen absorption capacity of the titanium-based hydrogen storage alloy blocks of Examples 1-12 and Comparative Examples 1-4 are shown in Table 1.

[0080] Table 1. Comparison of performance parameters of titanium-based hydrogen storage alloy blocks in Examples 1-12 and Comparative Examples 1-4.

[0081]

[0082] This invention has been described through the specific embodiments described above. Those skilled in the art should understand that various modifications and equivalent substitutions can be made to this invention without departing from its scope. Parts not described in detail in this specification are well-known to those skilled in the art. Furthermore, various modifications can be made to this invention for specific situations or circumstances without departing from its scope. Therefore, this invention is not limited to the specific embodiments disclosed, but should include all embodiments falling within the scope of the claims.

Claims

1. A method for preparing a titanium-based hydrogen storage alloy block, characterized in that, Includes the following steps: Step 1): According to the raw material ratio of the titanium-based hydrogen storage alloy block, the raw material powder is mixed in an inert atmosphere to obtain a mixed powder. The oxygen content of the mixed powder is greater than 0.35 wt.% and less than 0.65 wt.%. The titanium raw material in the raw material powder is titanium raw material containing titanium powder waste, the mass percentage of titanium powder waste in the titanium raw material is 25~75 wt.%, and the titanium raw material is doped with more than 0.5 wt.% and less than 2.0 wt.% FeCl3; Step 2): The mixed powder is pre-pressed in an inert atmosphere to obtain a titanium-based hydrogen storage alloy billet; Step 3): The titanium-based hydrogen storage alloy billet is placed in a sintering furnace, and a coating material is uniformly and loosely spread on the surface of the billet. The coating material has a thickness of 3-15 mm and a looseness of 1.0-2.0 g / cm³ per unit volume. 3 ; The coating material is titanium scrap or titanium powder waste doped with FeCl3, wherein the FeCl3 doping content in the coating material is greater than or equal to 1.0 wt.% and less than 4.0 wt.%. Step 4): The titanium-based hydrogen storage alloy billet with the coating material is sintered under the protection of high-purity argon gas at a sintering temperature of 850~1250 ℃ and a sintering time of 2~5 h to obtain a titanium shell-titanium-based hydrogen storage alloy block with titanium shell coating. After removing the titanium shell, a titanium-based hydrogen storage alloy block is obtained; The titanium powder waste is a metal powder with a particle size of 50-200 mesh. The titanium powder waste contains O < 0.45 wt.%, Fe < 0.3 wt.%, Si < 0.1 wt.%, Ni < 0.1 wt.%, Cu < 0.1 wt.%, Cr < 0.1 wt.%, and the balance is Ti. The titanium shavings are strip-shaped sheets with a width of about 5 mm. The titanium shavings contain O < 0.4 wt.%, Cr < 0.1 wt.%, Fe < 0.5 wt.%, Al < 0.65 wt.%, V < 0.1 wt.%, and the balance is Ti.

2. The method for preparing the titanium-based hydrogen storage alloy block according to claim 1, characterized in that, In step 4), the remaining amount of FeCl3 in the titanium shell is 5% to 30% of the initial content.

3. The method for preparing the titanium-based hydrogen storage alloy block according to claim 1, characterized in that, In step 4), the thickness of the titanium shell is 1~10 mm, and the titanium shell has a porous structure.

4. The method for preparing the titanium-based hydrogen storage alloy block according to claim 1, characterized in that, The oxygen content of the titanium-based hydrogen storage alloy block is greater than 0.2 wt.% and less than 0.65 wt.%.

5. The method for preparing the titanium-based hydrogen storage alloy block according to claim 1, characterized in that, The surface of the titanium-based hydrogen storage alloy block exhibits a metallic luster, and the titanium-based hydrogen storage alloy block does not contain the rare earth elements lanthanum, cerium, and yttrium.

6. The method for preparing the titanium-based hydrogen storage alloy block according to claim 1, characterized in that, The titanium-based hydrogen storage alloy block is any one of the Ti-Fe, Ti-Mn, Ti-Cr, and Ti-Co systems.

7. The method for preparing the titanium-based hydrogen storage alloy block according to claim 6, characterized in that, The Ti-Fe system is TiFe. 0.9 Mn 0.1 TiFe 0.8 Ni 0.2 TiFe 0.9 Al 0.1 Any one of them; The Ti-Mn system is Ti 0.9 Zr 0.2 Mn 1.8 V 0.2 Ti 1.2 MnCr, Ti 0.8 Zr 1.2 Mn 1.5 Cu 0.5 Any one of them; The Ti-Cr system is TiCr 1.8 Ti 1.2 Cr 1.2 Mn 0.8 Ti 0.8 Zr 0.2 CrMn 0.8 Co 0.2 Any one of them; The Ti-Co system is TiCo, TiCo 0.75 Ni 0.25 Ti 0.9 V 0.1 Any of Co.

8. The method for preparing the titanium-based hydrogen storage alloy block according to claim 1, characterized in that, In step 1), the mixing speed is 20~100 r / min and the mixing time is 30~180 min; in step 2), the pre-pressing pressure is 2~10 MPa and the holding time is 3~20 min.

9. The use of a titanium-based hydrogen storage alloy block, characterized in that, The titanium-based hydrogen storage alloy block is prepared by the method described in any one of claims 1 to 8. The titanium-based hydrogen storage alloy block does not require secondary processing or crushing and directly undergoes hydrogen absorption and desorption reactions at room temperature in the form of a complete block.

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