Tantalum powder preparation device and tantalum powder preparation method

Abstract

The invention relates to a tantalum powder preparation device and a tantalum powder preparation method. The tantalum powder preparation device comprises: a reaction container, in which a vessel is arranged, the vessel is used for containing materials for preparing tantalum powder, and the materials comprise tantalum oxide and magnesium powder; the collector is arranged in the reaction container, the collector comprises a top wall, a bottom wall and a circumferential side wall connected with the top wall and the bottom wall, the bottom wall covers the upper part of the vessel and is provided with a plurality of first through holes, the top wall is provided with a second through hole communicated with an evacuation pipeline, and the bottom wall is provided with a plurality of second through holes communicated with the evacuation pipeline. The collector is configured to collect magnesium vapor entering the collector through the plurality of first through holes. The residual excessive magnesium in the material is collected by the collector, so that the magnesium content in the final tantalum powder product can be obviously reduced, and the purity of the tantalum powder and the performance stability of the product are improved. And moreover, the metal magnesium collected by the collector can be recycled after being purified, so that the reutilization of resources is realized, the consumption of raw materials is reduced, and the potential pollution of magnesium-containing wastes to the environment is reduced.

Description

Technical Field

[0001] This invention relates to the field of rare metal material preparation technology, and in particular to a tantalum powder preparation apparatus and a tantalum powder preparation method. Background Technology

[0002] Tantalum electrolytic capacitors (hereinafter referred to as tantalum capacitors) have advantages such as high capacitance, small size, strong self-healing ability, and high reliability, and are widely used in high-end technology fields such as communications, computers, automotive electronics, medical devices, radar, aerospace, and automatic control devices. Tantalum powder is the key material for making tantalum capacitors; only by using capacitor-grade tantalum powder with higher voltage withstand performance can tantalum capacitors with better reliability be produced. Therefore, only by continuously developing capacitor-grade tantalum powder with higher voltage withstand performance can the produced tantalum capacitors continuously meet the high reliability requirements of electronic devices and electronic circuits.

[0003] In some related technologies, the industrial-scale preparation of capacitor-grade tantalum powder employs the magnesium reduction of tantalum oxide method. During the process of preparing tantalum powder using magnesium as a reducing agent, the amount of magnesium added is 1 to 5 times the theoretically required amount. After the reduction reaction, all excess magnesium in the material must be discharged; otherwise, it will be used together with the prepared tantalum powder and the byproduct magnesium oxide in the subsequent water acid washing process (pure water and inorganic acid will be added, preferably one or more of hydrochloric acid, nitric acid, sulfuric acid, and hydrogen peroxide). At this time, the excess magnesium will react violently with the inorganic acid, releasing a large amount of heat, leading to phenomena such as material boiling and spraying. This not only results in a significant loss of tantalum powder but also poses safety hazards to operators. Furthermore, it will also have a detrimental effect on the physicochemical properties of the tantalum powder, such as oxygen content and magnesium content. Summary of the Invention

[0004] Some embodiments of the present invention provide a tantalum powder preparation apparatus and a tantalum powder preparation method to solve the problem of poor performance of tantalum powder products caused by the inability to properly collect excess magnesium during the industrial production of certain magnesium reduction processes.

[0005] In one aspect of the present invention, a tantalum powder preparation apparatus is provided, comprising:

[0006] A reaction vessel containing a container for holding materials for preparing tantalum powder, the materials including tantalum oxide and magnesium powder; and

[0007] A collector is disposed within the reaction vessel. The collector includes a top wall, a bottom wall, and a circumferential side wall connecting the top wall and the bottom wall. The bottom wall covers the top of the vessel and is provided with a plurality of first through holes. The top wall is provided with a second through hole communicating with a vacuum pipe. The collector is configured to collect magnesium vapor entering therethrough through the plurality of first through holes.

[0008] In some embodiments, the collector has a trapezoidal cross-section, and the area of ​​the top wall is smaller than the area of ​​the bottom wall.

[0009] In some embodiments, the bottom wall is located 20cm to 40cm above the vessel.

[0010] In some embodiments, the tantalum powder preparation apparatus further includes:

[0011] A cooling assembly is located on the outer periphery of the reaction vessel, at a position corresponding to the collector.

[0012] In some embodiments, the tantalum powder preparation apparatus further includes:

[0013] An evacuation pipe passes through the top cover of the reaction vessel and communicates with the second through hole.

[0014] In some embodiments, the evacuation pipeline is configured to evacuate magnesium for 3 to 20 hours after the material reaction is completed.

[0015] In some embodiments, the evacuation conduit is configured to have an evacuation pressure of -0.1 MPa to -0.05 MPa.

[0016] In some embodiments, the tantalum powder preparation apparatus further includes:

[0017] A heating component is disposed outside the reaction vessel and configured to heat the material. The heating component is configured to control the material temperature at 650°C to 850°C after the material reaction is completed.

[0018] In some embodiments, the tantalum powder preparation apparatus further includes:

[0019] A heating element is located outside the reaction vessel and is configured to control the material temperature at 850°C to 1000°C during the material reaction process.

[0020] In some embodiments, the collector is made of a nickel-based alloy material.

[0021] In one aspect of the present invention, a method for preparing tantalum powder is provided, employing the aforementioned tantalum powder preparation apparatus, wherein the tantalum powder preparation method includes the following steps:

[0022] S10 involves placing materials for preparing tantalum powder into a vessel within a reaction vessel and subjecting the materials to a reduction reaction to prepare tantalum powder; the materials include tantalum oxide and magnesium powder; and

[0023] After the S20 material reduction reaction is completed, magnesium vapor in the reaction vessel is collected by a collector.

[0024] In some embodiments, in step S20, after the material reduction reaction is completed, the material temperature is first controlled to 650°C~850°C, and then magnesium vapor in the reaction vessel is collected by a collector.

[0025] In some embodiments, in step S20, a suction force is provided through a evacuation pipe to allow magnesium vapor to enter the collector, and the evacuation time of the evacuation pipe is controlled to be 3h~20h so that the collector can collect magnesium vapor in the reaction vessel.

[0026] In some embodiments, in step S20, the evacuation pressure in the evacuation pipe is -0.1MPa to -0.05MPa.

[0027] In some embodiments, in step S10, the material temperature is controlled at 850℃~1000℃ and kept at that temperature for 1h~10h, and the pressure inside the reaction vessel is controlled at 0.1MPa~0.15MPa, so that the material undergoes a reduction reaction to prepare tantalum powder.

[0028] Based on the above technical solution, the present invention has at least the following beneficial effects:

[0029] In the above embodiments, a collector is installed above the reaction zone inside the reaction vessel. After the magnesium reduction of tantalum oxide reaction is completed, a negative pressure is applied to the interior of the reaction vessel through a vacuum pipe. This allows residual excess magnesium to be drawn into the inner cavity of the collector in vapor form, where it condenses and accumulates. This process effectively captures the residual excess magnesium in the material, significantly reducing the magnesium content in the final tantalum powder product, thereby improving the purity and performance stability of the tantalum powder. Furthermore, the collected metallic magnesium can be purified and recycled, achieving resource reuse, reducing raw material consumption, and minimizing the potential environmental pollution from magnesium-containing waste. Attached Figure Description

[0030] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0031] Figure 1 This is a schematic diagram of the structure of a tantalum powder preparation apparatus provided according to some embodiments of the present invention;

[0032] Figure 2 The image shows the morphology of tantalum powder prepared using the tantalum powder preparation apparatus provided in this embodiment of the invention.

[0033] The labels in the attached diagram are explained as follows:

[0034] 1-Reaction vessel; 11-Vessel; 12-Resource rack; 13-Top cover;

[0035] 2-Collector; 21-Top wall; 22-Bottom wall; 23-Circumferential side wall;

[0036] 3-Evacuation pipe;

[0037] 4-Cooling components;

[0038] 5-Heating component; 51-Resistant furnace; 52-Resistant strip; 53-Connector; 54-Insulation layer.

[0039] It should be understood that the dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Furthermore, the same or similar reference numerals denote the same or similar components. Detailed Implementation

[0040] Various exemplary embodiments of the invention will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are in no way intended to limit the invention or its application or use. The invention can be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the invention thorough and complete, and to fully express the scope of the invention to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values ​​set forth in these embodiments should be interpreted as merely exemplary and not as limiting.

[0041] The terms "first," "second," and similar words used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Words such as "including" or "comprising" mean that the element preceding the word encompasses the element listed after it, without excluding the possibility of encompassing other elements. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0042] In this invention, when a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other devices without an intermediary device, or it may be not directly connected to the other devices but have an intermediary device.

[0043] All terms used in this invention (including technical or scientific terms) have the same meaning as understood by one of ordinary skill in the art to which this invention pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and not as idealized or highly formalized, unless expressly defined herein.

[0044] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0045] In the process of reducing tantalum oxide with magnesium to produce tantalum powder, a large amount of magnesium is required as a reducing agent, typically 1 to 5 times the theoretically required amount. Therefore, a large amount of unreacted magnesium remains after the reaction. If this excess magnesium is not effectively collected and processed, it will not only waste resources and increase production costs, but also result in high levels of impurities such as magnesium and oxygen in the final tantalum powder product, affecting product purity and electrochemical performance. Traditional reduction furnace structures lack a dedicated magnesium vapor recovery mechanism, making it difficult to meet the high magnesium vapor emission demands of large-scale production.

[0046] To address the technical problems mentioned above regarding the difficulty in effectively collecting excess metallic magnesium during the magnesium reduction of tantalum oxide, which affects the performance of tantalum powder and production safety, some embodiments of the present invention provide a tantalum powder preparation apparatus and method. This apparatus and method, by integrating a collector with a through-hole structure inside the reaction vessel and combining it with an external evacuation system, can actively guide the volatilized magnesium vapor to the collector for directional condensation and centralized collection after the reduction reaction. This apparatus and method not only significantly improve the recovery efficiency of excess magnesium, reduce environmental pollution and raw material loss, but also reduce the magnesium and oxygen impurity content in the final tantalum powder, improving product purity. It is particularly suitable for large-scale industrial production scenarios, significantly improving production efficiency, operational safety, and resource recycling rate while ensuring the excellent performance of tantalum powder, thereby reducing overall production costs.

[0047] Figure 1 This is a schematic diagram of the structure of some embodiments of the tantalum powder preparation apparatus according to the present invention.

[0048] refer to Figure 1 In some embodiments, the tantalum powder preparation apparatus includes a reaction vessel 1 and a collector 2.

[0049] The reaction zone inside the reaction vessel 1 is equipped with a vessel 11, which holds materials for preparing tantalum powder, including tantalum oxide and magnesium powder. Optionally, the materials also include a diluent, the main function of which is to absorb the large amount of heat generated by the magnesium reduction of tantalum oxide reaction.

[0050] Collector 2 is located above the reaction zone within reaction vessel 1. Collector 2 includes a top wall 21, a bottom wall 22, and a circumferential side wall 23. The circumferential side wall 23 connects the top wall 21 and the bottom wall 22. The top wall 21 is located away from the reaction zone relative to the bottom wall 22. The bottom wall 22 covers the vessel 11 and has multiple first through holes. The top wall 21 is located above the bottom wall 22. The top wall 21 has a second through hole communicating with the evacuation pipe 3. Collector 2 is configured to collect magnesium vapor entering it through the multiple first through holes.

[0051] In the above embodiment, the vessel 11 is disposed within the reaction zone of the reaction container 1. The collector 2 is located above the reaction zone. The bottom wall 22 is closer to the vessel 11 than the top wall 21.

[0052] In the above embodiment, a collector 2 is installed above the reaction zone inside the reaction vessel 1. During the high-temperature reaction of magnesium reducing tantalum oxide, the reducing agent magnesium evaporates due to the high temperature, forming magnesium vapor. Some of the magnesium vapor rises and enters the interior of the collector 2 through multiple first through holes on the bottom wall 22. Furthermore, after the magnesium reducing tantalum oxide reaction is completed, a negative pressure is applied to the interior of the reaction vessel 1 through the evacuation pipe 3, which can draw the remaining excess magnesium in vapor form into the inner cavity of the collector 2. Because the temperature of the area where the collector 2 is located is relatively low, the magnesium vapor condenses in the condensation zone formed by the top wall 21, bottom wall 22, and circumferential sidewalls 23 of the collector 2, forming solid or liquid magnesium, which accumulates on the top wall 21, bottom wall 22, and circumferential sidewalls 23. Therefore, by setting up the collector 2, the excess magnesium can be effectively captured. After the excess magnesium is collected and the material cools down, the condensed magnesium in the collector 2 can be centrally cleaned and recovered.

[0053] In the above embodiment, the bottom wall 22 of the collector 2 is provided with multiple first through holes. This structure allows magnesium vapor to smoothly enter the interior of the collector 2, while preventing condensed magnesium in the collector 2 from flowing back into the reaction zone of the vessel 11 due to gravity or vibration. The top wall 21 of the collector 2 is provided with a second through hole that communicates with the evacuation pipe 3. The evacuation pipe 3 provides continuous suction to the interior of the collector 2 through the second through hole, driving magnesium vapor in the reaction zone of the reaction vessel 1 to flow directionally into the collector 2, ensuring that excess magnesium is efficiently removed. The condensation and accumulation area formed by the top wall 21, bottom wall 22, and circumferential sidewalls 23 of the collector 2 is conducive to the full condensation and deposition of magnesium vapor, improving the magnesium recovery rate.

[0054] In the above embodiments, after the magnesium reduction of tantalum oxide reaction is completed and magnesium vapor is removed, collector 2 can effectively capture excess residual magnesium in the material, significantly reducing the magnesium content in the final tantalum powder product, thereby improving the purity and performance stability of the tantalum powder. Furthermore, after cooling the entire device to room temperature, the magnesium crystals or solids deposited in collector 2 can be collected and processed centrally. The recovered metallic magnesium can be purified and recycled, realizing resource reuse, reducing raw material consumption, and simultaneously reducing the potential environmental pollution from magnesium-containing waste. This aligns with the technological trends of green manufacturing and sustainable development, demonstrating significant environmental and economic benefits.

[0055] In some embodiments, the tantalum powder preparation apparatus further includes a material rack 12. The material rack 12 is disposed within the reaction zone of the reaction vessel 1. A vessel 11 is placed on the material rack 12, and the vessel 11 contains materials such as tantalum oxide to be reduced. A collector 2 is located above the material rack 12.

[0056] In some embodiments, the vessel 11 includes a crucible. Multiple crucibles may be arranged vertically on the rack 12.

[0057] In some embodiments, the collector 2 has a trapezoidal cross-section, and the area of ​​the top wall 21 is smaller than the area of ​​the bottom wall 22.

[0058] In the above embodiment, the collector 2 has a trapezoidal cross-section, giving its bottom wall 22 a large area that effectively covers the area above the vessel 11. This facilitates the uniform and smooth entry of magnesium vapor into the collector 2 through the multiple first through holes on the bottom wall 22, improving the magnesium vapor capture efficiency. The top wall 21 of the collector 2 has a smaller area and is equipped with a second through hole that connects to the evacuation pipe 3. This helps to create a more concentrated and stable negative pressure airflow field inside the collector 2 during the vacuuming process, promoting the directional flow of magnesium vapor from bottom to top along the axial direction and reducing eddies or airflow backflow, thereby improving the magnesium vapor transmission efficiency and condensation collection effect. Furthermore, the circumferential sidewall 23 of the collector 2 is an inclined sidewall, which increases the area and facilitates the flow and accumulation of condensed solid or liquid magnesium along the circumferential sidewall 23 under gravity, improving the magnesium recovery effect.

[0059] In some embodiments, the bottom wall 22 is located 20cm to 40cm above the vessel 11.

[0060] In some embodiments, the container 11 is located in a position corresponding to the reaction zone. The bottom wall 22 is located 20cm to 40cm above the reaction zone, or the bottom wall 22 is located 20cm to 40cm above the material rack 12.

[0061] In the above embodiments, setting the bottom wall 22 of the collector 2 at a specific height of 20cm to 40cm above the top of the vessel 11 provides sufficient buffer and transition space for magnesium vapor to diffuse upward from the reaction zone (the area where the vessel 11 is located). If the height is too small, the safe distance between the collector 2 and the reactants may be insufficient, posing a risk of magnesium condensation backflow or thermal radiation affecting reaction control; if the height is too large, magnesium vapor may condense prematurely or deposit on the wall of the reaction vessel 1 during transport, affecting collection efficiency and increasing the overall height of the reaction vessel 1, leading to increased costs. Therefore, setting the bottom wall 22 20cm to 40cm above the top of the vessel 11 ensures good gas phase transport and condensation collection while reducing the volume of the reaction vessel 1.

[0062] In some embodiments, collector 2 is configured as a frustum.

[0063] In some embodiments, the tantalum powder preparation apparatus further includes a cooling component 4, which is disposed on the outer periphery of the reaction vessel 1 and corresponds to the location of the collector 2.

[0064] In the above embodiment, the interior of collector 2 is a condensation zone for magnesium vapor, and the exterior of collector 2, corresponding to the outer wall of reaction vessel 1, is equipped with a cooling component 4. This component provides directional and localized cooling to the area where collector 2 is located, effectively reducing the temperature inside collector 2 and creating a large temperature gradient between the interior of collector 2 and the reaction zone. This allows magnesium vapor to be rapidly cooled and efficiently condensed when it enters collector 2, promoting uniform and stable crystallization and precipitation of magnesium on the inner wall of collector 2. This reduces the risk of liquid magnesium dripping or secondary volatilization, ensuring that excess magnesium is captured promptly and thoroughly. Furthermore, since the cooling component 4 is located on the outer periphery of reaction vessel 1, there is no need to directly introduce the cooling medium into the interior of reaction vessel 1, reducing the impact on the high-temperature reaction zone.

[0065] In some embodiments, the cooling assembly 4 includes cooling water pipes wound around the outer periphery of the reaction vessel 1, corresponding to the area of ​​the collector 2, for reducing the temperature inside the collector 2.

[0066] In some embodiments, the tantalum powder preparation apparatus further includes a vacuum pipe 3. The reaction vessel 1 includes a top cover 13 located at the top, and a collector 2 located below the top cover 13. The vacuum pipe 3 passes through the top cover 13 of the reaction vessel 1 and communicates with a second through hole on the top wall 21 of the collector 2.

[0067] In the above embodiment, the evacuation pipe 3 is introduced through the top cover 13 of the reaction vessel 1 and communicates with the second through hole on the top wall 21 of the collector 2, forming a directional suction channel from the reaction zone to the interior of the collector 2. After the magnesium reduction reaction is completed, by activating the evacuation system connected to the evacuation pipe 3, a controllable negative pressure environment can be established in the reaction vessel 1, driving the residual excess magnesium in vapor form to pass through multiple first through holes on the bottom wall 22 of the collector 2 from bottom to top, and enter the interior space of the collector 2 for centralized condensation, which is beneficial to achieve efficient and rapid collection of magnesium vapor.

[0068] In some embodiments, the evacuation pipe 3 is configured to evacuate magnesium for 3 to 20 hours after the material reaction is completed.

[0069] In some embodiments, the evacuation pipe 3 is configured to evacuate magnesium for 3h to 15h, or 5h to 20h, after the material reaction is completed. Optionally, the evacuation pipe 3 is configured to evacuate magnesium for 3h, 5h, 10h, 15h, or 20h after the material reaction is completed.

[0070] In the above embodiments, after the magnesium reduction of tantalum oxide reaction is completed, a large amount of unreacted excess metallic magnesium remains in reaction vessel 1. This magnesium continues to volatilize at high temperatures, forming magnesium vapor. Negative pressure is applied through evacuation pipe 3 to continuously draw the magnesium vapor into collector 2 for condensation and collection. If the evacuation time is too short (less than 3 hours), the residual magnesium vapor cannot be fully discharged, resulting in some excess magnesium remaining in the reaction zone or adhering to the surface of the tantalum powder. This leads to an increase in magnesium and oxygen impurities in the final product, affecting the purity and electrochemical performance of the tantalum powder; it may also increase the safety risks of subsequent processing due to magnesium residue. If the evacuation time is too long (more than 20 hours), it will prolong the production cycle, reduce equipment turnover efficiency, and is not conducive to large-scale continuous production. Therefore, controlling the magnesium removal time within the range of 3 to 20 hours achieves a good balance between magnesium removal efficiency, product purity, production efficiency, and process safety. Within this time, excess magnesium in reaction vessel 1 can be effectively and almost completely removed in vapor form, significantly reducing the magnesium and oxygen content in the tantalum powder and improving product quality.

[0071] In some embodiments, the tantalum powder preparation apparatus further includes a evacuation system connected to the evacuation pipe 3. The evacuation system provides evacuation pressure or negative pressure to the evacuation pipe 3.

[0072] In some embodiments, the evacuation pipe 3 is configured to have an evacuation pressure of -0.1 MPa to -0.05 MPa.

[0073] In the above embodiments, controlling the evacuation pressure of the evacuation pipe 3 at -0.1 MPa to -0.05 MPa creates a stable vacuum environment inside the reaction vessel 1, causing the residual metallic magnesium to continuously volatilize and flow directionally under high temperature conditions, entering the collector 2 through the first through-hole on the bottom wall 22. Simultaneously, this negative pressure environment effectively enhances the airflow driving force, enabling magnesium vapor to migrate rapidly and completely from the reaction zone to the cooling area of ​​the collector 2, preventing it from condensing and flowing back in the reaction zone or adhering to the surface of the tantalum powder product.

[0074] In the above embodiments, if the evacuation pressure is too high (i.e., insufficient vacuum, such as greater than -0.05 MPa), magnesium vapor diffusion is hindered, migration rate decreases, resulting in insufficient magnesium removal and affecting the purity and magnesium removal rate of the final tantalum powder. If the evacuation pressure is too low (i.e., excessive vacuum, such as below -0.1 MPa), it increases the difficulty of system sealing and the risk of leakage, and may also cause fine particles such as tantalum powder to be carried into collector 2 by the strong airflow. Therefore, setting the evacuation pressure in the range of -0.1 MPa to -0.05 MPa can not only efficiently remove excess magnesium, significantly reduce the content of magnesium and oxygen impurities in tantalum powder, and improve the chemical stability and electrochemical performance of the product, but also enhance process controllability, making it suitable for continuous industrial production and conducive to the stable preparation of high-quality tantalum powder.

[0075] In some embodiments, the tantalum powder preparation apparatus further includes a heating assembly 5. The heating assembly 5 is located outside the reaction vessel 1 and is configured to heat the materials.

[0076] Since excess magnesium needs to be removed after reducing tantalum oxide with magnesium as a reducing agent to prepare tantalum powder, the vapor pressure of magnesium metal varies with temperature, based on the melting point of magnesium being 650℃ and the boiling point being 1107℃. Table 1 below shows the variation of magnesium metal vapor pressure with temperature.

[0077] Table 1. Vapor pressure of magnesium metal as a function of temperature

[0078] As can be seen from the vapor pressure of magnesium, magnesium has a relatively large vapor pressure between 650℃ and 1000℃, and magnesium can be removed by vacuuming in all of these temperatures.

[0079] Based on this, the heating component 5 is configured to control the material temperature at 650℃~850℃ after the material reaction is completed.

[0080] In the above embodiments, the heating component 5 is disposed outside the reaction vessel 1, which can uniformly and controllably heat the material (a mixture of tantalum oxide and magnesium powder) inside the vessel 11, ensuring that the magnesium reduction reaction is successfully started and fully carried out under high temperature conditions.

[0081] After the reduction reaction, the heating component 5 continues to operate, maintaining the temperature of the reaction zone within a specific range of 650℃ to 850℃. This provides the necessary thermodynamic conditions for the subsequent "vacuum-driven magnesium removal" process via the evacuation pipe 3. Within this temperature range, metallic magnesium has a high saturated vapor pressure, enabling it to continuously and stably volatilize and form magnesium vapor, which then migrates directionally into the collector 2 under vacuum. If the temperature is below 650℃, the magnesium vapor pressure is too low, and the volatilization rate decreases significantly, resulting in insufficient magnesium removal and difficulty in effectively removing residual magnesium. If the temperature is above 850℃, it may cause agglomeration or sintering of tantalum powder particles. Therefore, controlling the material temperature at 650℃ to 850℃ after the reaction ensures that excess magnesium is efficiently and thoroughly extracted in vapor form and condensed and collected in the collector 2, significantly reducing the residual magnesium content in the final tantalum powder product and improving product purity and consistency.

[0082] In the above embodiments, the temperature range of 650℃ to 850℃, along with process parameters such as evacuation pressure (-0.1MPa to -0.05MPa) and evacuation time (3h to 20h), are coordinated to form a complete magnesium removal process system of "high-temperature volatilization + negative pressure drive + directional condensation", which improves the magnesium recovery rate.

[0083] In some embodiments, the heating assembly 5 includes a resistance furnace 51. The reaction vessel 1 is placed inside the resistance furnace 51. The resistance furnace 51 is provided with a heat insulation layer 54, which is in contact with the outer wall of the reaction vessel 1, to reduce heat loss in the reaction zone, improve heating efficiency, and achieve uniform temperature distribution.

[0084] In some embodiments, the resistance furnace 51 is further provided with a resistance band 52. The resistance band 52 serves as a heating element, generating heat when energized, and heating the reaction zone of the reaction vessel 1 through convection and radiation, thereby providing the required high-temperature environment for the magnesium reduction reaction of the materials.

[0085] In some embodiments, the resistance strip 52 is fixed to the insulation layer 54 by the connector 53, which can realize the stable installation and positioning of the resistance strip 52 and ensure the safety and reliability of the heating process.

[0086] In some embodiments, the tantalum powder preparation apparatus further includes a heating component 5. The heating component 5 is disposed outside the reaction vessel 1 and is configured to control the material temperature at 850°C to 1000°C during the material reaction process.

[0087] In the above embodiments, controlling the material temperature within the range of 850℃ to 1000℃ during the magnesium reduction of tantalum oxide to prepare tantalum powder ensures that metallic magnesium possesses sufficient activity and fluidity to fully react with tantalum oxide, generating metallic tantalum and magnesium oxide as byproducts. If the reaction temperature is below 850℃, the reducing power of magnesium is insufficient, potentially leading to incomplete reduction and residual unreacted tantalum oxide, affecting the purity and chemical consistency of the tantalum powder. If the temperature exceeds 1000℃, it may exacerbate the vigorous volatilization of magnesium, causing excessive loss of the reducing agent and potentially causing sintering of the tantalum powder particles. Therefore, controlling the material temperature during the reaction process within the range of 850℃ to 1000℃ achieves a balance between reaction completeness, product quality, equipment safety, and energy consumption.

[0088] In some embodiments, collector 2 is made of a nickel-based alloy. Of course, collector 2 can also be made of other high-temperature resistant materials that do not react with magnesium.

[0089] In the above embodiments, the nickel-based alloy has excellent high-temperature strength, good thermal stability, and resistance to hot corrosion and oxidation. It can withstand high temperatures during the preparation of tantalum powder without deformation, cracking or performance degradation, ensuring the structural integrity and service life of collector 2 under repeated thermal cycling.

[0090] Some embodiments of the present invention also provide a method for preparing tantalum powder, using the above-described tantalum powder preparation apparatus, wherein the tantalum powder preparation method includes the following steps:

[0091] S10 places the materials used to prepare tantalum powder into a vessel 11 within the reaction vessel 1, and allows the materials to undergo a reduction reaction to prepare tantalum powder; the materials include tantalum oxide and magnesium powder, etc.; and

[0092] After the material reduction reaction is completed, S20 collects the magnesium vapor in the reaction vessel 1 through collector 2.

[0093] In the above embodiment, after the material reduction reaction is completed, a negative pressure is created in the collector 2 using the evacuation pipe 3. This drives the residual excess magnesium in vapor form through multiple first through holes on the bottom wall 22 of the collector 2, into the interior of the collector 2, where it is cooled and condensed on its inner wall surface. This achieves the targeted collection and centralized recovery of the excess reducing agent. Through active suction and condensation recovery, the magnesium and oxygen impurity content in the final tantalum powder is significantly reduced, improving product purity and electrochemical performance. Furthermore, the recovered metallic magnesium can be recycled after processing, reducing resource waste and lowering production costs.

[0094] In some embodiments, in step S20, after the material reduction reaction is completed, the material temperature is first controlled to 650°C~850°C, and then magnesium vapor in the reaction vessel 1 is collected by collector 2.

[0095] In the above embodiments, maintaining the temperature of the reaction zone within a specific range of 650℃ to 850℃ after the material reduction reaction is completed provides the necessary thermodynamic conditions for the subsequent "vacuum magnesium removal" process via the evacuation pipe 3. Within this temperature range, metallic magnesium has a high saturated vapor pressure, enabling it to continuously and stably volatilize to form magnesium vapor, which then migrates directionally into the collector 2 under vacuum. If the temperature is below 650℃, the magnesium vapor pressure is too low, and the volatilization rate decreases significantly, resulting in insufficient magnesium removal and difficulty in effectively removing residual magnesium. If the temperature is above 850℃, it may cause agglomeration or sintering of tantalum powder particles. Therefore, controlling the material temperature at 650℃ to 850℃ after the reaction can promote the efficient and thorough extraction and condensation of excess magnesium in the form of vapor in the collector 2, significantly reducing the residual magnesium content in the final tantalum powder product and improving the purity and consistency of the product.

[0096] In some embodiments, in step S20, a suction force is provided through the evacuation pipe 3 to allow magnesium vapor to enter the collector 2, and the evacuation time of the evacuation pipe 3 is controlled to be 3h~20h, so that the collector 2 collects the magnesium vapor in the reaction vessel 1.

[0097] In the above embodiments, after the magnesium reduction of tantalum oxide reaction is completed, a large amount of unreacted excess metallic magnesium remains in reaction vessel 1. This magnesium continues to volatilize at high temperatures, forming magnesium vapor. Negative pressure is applied through evacuation pipe 3 to continuously draw the magnesium vapor into collector 2 for condensation and collection. If the evacuation time is too short (less than 3 hours), the residual magnesium vapor cannot be fully discharged, resulting in some excess magnesium remaining in the reaction zone or adhering to the surface of the tantalum powder. This leads to an increase in magnesium and oxygen impurities in the final product, affecting the purity and electrochemical performance of the tantalum powder; it may also increase the safety risks of subsequent processing due to magnesium residue. If the evacuation time is too long (more than 20 hours), it will prolong the production cycle, reduce equipment turnover efficiency, and is not conducive to large-scale continuous production. Therefore, controlling the magnesium removal time within the range of 3 to 20 hours achieves a good balance between magnesium removal efficiency, product purity, production efficiency, and process safety. Within this time range, excess magnesium in reaction vessel 1 can be effectively and almost completely removed in vapor form, significantly reducing the magnesium and oxygen content in the tantalum powder and improving product consistency and quality stability.

[0098] In some embodiments, in step S20, the evacuation pressure in the evacuation pipe 3 is -0.1MPa to -0.05MPa.

[0099] In the above embodiments, controlling the evacuation pressure of the evacuation pipe 3 at -0.1MPa to -0.05MPa creates a stable vacuum environment inside the reaction vessel 1, promoting the continuous volatilization and directional flow of residual magnesium metal under high-temperature conditions. The magnesium vapor then enters the collector 2 through the first through-hole on the bottom wall 22. Simultaneously, this negative pressure environment effectively enhances the airflow driving force, promoting the rapid and complete migration of magnesium vapor from the reaction zone to the cooling area of ​​the collector 2, preventing it from condensing and flowing back into the reaction zone or adhering to the surface of the tantalum powder product.

[0100] In some embodiments, in step S10, the material temperature is controlled at 850℃~1000℃ and kept at that temperature for 1h~10h, and the pressure inside the reaction vessel 1 is controlled at 0.1MPa~0.15MPa, so that the material undergoes a reduction reaction to prepare tantalum powder.

[0101] In the above embodiments, controlling the material temperature within the range of 850℃ to 1000℃ ensures that the magnesium powder is fully melted and possesses good fluidity and reactivity, thereby effectively reducing tantalum oxide to metallic tantalum. The holding time is set to 1h to 10h, providing sufficient time for complete reduction of tantalum oxide; too short a time results in incomplete reaction, affecting product purity; too long a time reduces production efficiency. Controlling the pressure inside reaction vessel 1 at 0.1MPa to 0.15MPa (slightly higher than atmospheric pressure) helps suppress excessive volatilization of magnesium at high temperatures and reduces ineffective loss of the reducing agent.

[0102] In some embodiments, the method for preparing tantalum powder using a tantalum powder preparation apparatus includes the following steps:

[0103] 1) Prepare tantalum oxide, diluent, and magnesium powder reducing agent at 1.1 to 5 times the required dosage. Mix them evenly and place them in container 11 inside reaction vessel 1 for high-temperature reduction reaction.

[0104] 2) After the material reduction reaction is completed, the material temperature is reduced to 650℃~850℃, and magnesium is evacuated through the evacuation pipe 3 on the top cover 13 of the reaction vessel 1 for 3h~20h. During the evacuation process, excess reducing agent magnesium in the material is evacuated and cooled to the condensation zone of the collector 2.

[0105] 3) After the magnesium is removed by evacuation, the material in reaction vessel 1 is cooled to room temperature, and the tantalum powder in reaction vessel 1 is passivated.

[0106] 4) The tantalum powder material is discharged from the furnace, washed with water, acid-washed and dried to obtain tantalum powder raw powder;

[0107] 5) The tantalum powder raw powder undergoes the following processes: any 2 to 3 of the following processes can be selected: tantalum powder molten salt assisted heat treatment, high temperature heat treatment, deoxidation, etc.

[0108] 6) Perform the necessary water washing, acid washing, drying and powdering steps according to the process selected in 5) to obtain the final tantalum powder product.

[0109] 7) Finally, clean and collect the reducing agent magnesium crystal blocks collected in collector 2.

[0110] The following is in conjunction with the appendix Figure 1 Detailed description of some specific embodiments of tantalum powder preparation apparatus and tantalum powder preparation methods.

[0111] refer to Figure 1 In some specific embodiments, the tantalum powder preparation apparatus includes: a reaction vessel 1, a collector 2, an evacuation pipe 3, a cooling component 4, and a heating component 5.

[0112] The reaction vessel 1 includes a rack 12 located within its reaction zone, on which a vessel 11 is placed for holding materials. The reaction vessel 1 also includes a top cover 13 that seals the internal cavity of the reaction vessel 1. A collector 2 is located inside the reaction vessel 1, above the reaction zone and below the top cover 13. The collector 2 includes a top wall 21, a bottom wall 22, and a circumferential side wall 23. The circumferential side wall 23 connects the top wall 21 and the bottom wall 22. The top wall 21 is located away from the reaction zone of the reaction vessel 1 relative to the bottom wall 22. The bottom wall 22 has multiple first through holes, and the top wall 21 has a second through hole communicating with the evacuation pipe 3. The heating assembly 5 includes a resistance furnace 51, a resistance band 52, a connector 53, and an insulation layer 54. The reaction vessel 1 is placed inside the resistance furnace 51. The insulation layer 54 contacts the outer wall of the reaction vessel 1 to reduce heat loss, improve heating efficiency, and achieve uniform temperature distribution. The resistance band 52 serves as a heating element. When energized, it generates heat, which heats the reaction vessel 1 through convection and radiation, thereby providing the necessary high-temperature environment for the magnesium reduction reaction of the materials. The resistance band 52 is fixed to the insulation layer 54 by the connector 53, achieving stable installation and positioning.

[0113] An evacuation pipe 3 is installed on the top cover 13 of the reaction vessel 1. The first end of the evacuation pipe 3 is connected to the second through hole, and the second end of the evacuation pipe 3 is connected to an external evacuation system. The evacuation system includes a mechanical evacuation pump, etc. The top wall 21 of the collector 2 has one or two holes, and the bottom wall 22 is a perforated baffle. During the high-temperature heating process of magnesium reduction of tantalum oxide, some magnesium vapor rises to the condensation zone of the collector 2 and condenses. At the same time, after the magnesium reduction of tantalum oxide reaction is completed, the excess reducing agent magnesium vapor is evacuated by the evacuation system, and a large amount of magnesium vapor is drawn to the condensation zone of the collector 2, where it condenses into solid crystalline magnesium.

[0114] In some specific embodiments, the tantalum powder preparation method includes the following steps:

[0115] 1) Mix tantalum oxide, diluent, and magnesium powder (reducing agent) at 1.1 to 3 times the required amount evenly and place them in a crucible on the rack 12 in the reaction zone of reaction container 1; then place the reaction container 1 containing the materials in a pit-type resistance furnace 51, evacuate the reaction container 1 and replace it with an inert gas - argon, then heat it to 850℃~1000℃ and hold it for 1h~10h to allow the materials to fully reduce and react.

[0116] 2) After the material reduction reaction is completed, the material temperature is reduced to 650℃~800℃, and then a mechanical vacuum pump is used to provide power to the evacuation pipeline 3 to remove magnesium vapor from the reaction vessel 1 for 3h~15h, so that the magnesium vapor continues to condense in the collector 2.

[0117] 3) After the magnesium is removed by evacuation, the material in reaction vessel 1 is cooled to room temperature and then passivated.

[0118] 4) The material is discharged from the furnace, washed with water, acid-washed, and dried to obtain tantalum powder raw powder;

[0119] 5) The tantalum powder raw powder undergoes subsequent processes such as tantalum powder molten salt assisted heat treatment, high temperature heat treatment, and deoxidation;

[0120] 6) Perform the necessary washing, acid washing, drying, and powdering steps according to the process selected in 5) to obtain the final tantalum powder product, refer to... Figure 2 .

[0121] 7) Finally, the excess reducing agent magnesium collected in collector 2 is cleaned up and collected.

[0122] The tantalum powder preparation apparatus and method provided in this embodiment of the invention produce tantalum powder with good performance, low oxygen content, low magnesium content, and the ability to recover excess magnesium, thus achieving resource reuse.

[0123] The following examples and comparative examples provide further illustration.

[0124] Example:

[0125] Mix 50.0 kg of tantalum oxide (Ta2O5), diluent, and 37.8 kg of magnesium powder (theoretically, 13.5 kg of magnesium is needed to completely remove oxygen from tantalum oxide, so the excess magnesium weight is 24.3 kg or more). Place the mixture evenly in a vessel 11 inside reaction vessel 1. Then place reaction vessel 1 inside a pit-type resistance furnace 51. Secure the top cover 13 and the fixing screws of reaction vessel 1, as well as the evacuation pipe 3 and evacuation system. Evacuate and replace the gas inside reaction vessel 1, and fill it with inert gas—Ar. During the heating process, maintain the pressure inside reaction vessel 1 at 0.1 MPa~0.15 MPa, heat to 930℃, and hold for 2 hours.

[0126] Then the temperature is lowered to 750℃. At this point, the excess magnesium vapor in the reaction vessel 1 still has a high vapor pressure. Then the evacuation system is used to provide power to the evacuation pipe 3 to evacuate the excess magnesium vapor in the reaction vessel 1 to the condensation zone of the collector 2, so that the magnesium vapor cools and forms solid magnesium grains.

[0127] After evacuating through evacuation pipe 3 for 15 hours, once the excess magnesium has been evacuated and vented, the material in reaction vessel 1 is cooled to room temperature and passivated.

[0128] Next, the material in reaction vessel 1 was subjected to water acid washing to separate tantalum powder, which was then dried and sieved to obtain raw tantalum powder. The weight of the collected tantalum powder was 41 kg, the oxygen content was 3500 ppm, the magnesium content was 5 ppm, and the collected magnesium was 21.9 kg.

[0129] In the above embodiments, no material spraying phenomenon caused by excessive heat generation occurred during the acid washing process, thus avoiding harm to personal safety and loss of tantalum powder. The tantalum powder raw powder is then subjected to subsequent high-temperature heat treatment and deoxidation processes to obtain the tantalum powder product. The electrical properties of the final tantalum powder product are significantly better than those of the comparative example, as shown in Table 2.

[0130] Comparative example:

[0131] After thoroughly mixing 50.0 kg of tantalum oxide (Ta2O5), diluent, and 37.8 kg of magnesium powder (theoretically, 13.5 kg of magnesium is needed to completely remove oxygen from tantalum oxide, so the excess magnesium weight is 24.3 kg or more), the mixture is placed in a reaction vessel. The gas inside the reaction vessel is then evacuated and replaced with an inert gas—Ar. During the heating process, the pressure inside the reaction vessel is maintained at 0.1 MPa~0.15 MPa. The temperature is raised to 930℃ and held for 2 hours.

[0132] Then the temperature is lowered to 750°C. At this point, the excess magnesium vapor in the reaction vessel still has a high vapor pressure. The vessel is evacuated directly for 15 hours through the evacuation pipe. Then the material in the reaction vessel is cooled to room temperature and passivated (same as in the example).

[0133] Upon opening the reaction vessel, a large amount of residual magnesium was found in the material and even on the lid of the material crucible. This was because there was no collector 2 installed, and the magnesium was directly drawn into the evacuation pipe, causing blockage. This prevented the complete removal of the large amount of magnesium from the reaction vessel. Furthermore, the absence of collector 2 to collect this large amount of magnesium also caused magnesium vapor to condense and flow back onto the material rack.

[0134] Next, the material in the reaction vessel is subjected to acid washing to separate tantalum powder. During the acid washing process, a large amount of residual magnesium generates a large amount of heat, which causes the material to boil and spray, endangering personal safety and causing serious loss of tantalum powder.

[0135] After drying and sieving, tantalum powder was obtained. 15 kg of tantalum powder was collected (significant loss), with an oxygen content of 8100 ppm and a magnesium content of 45 ppm. 4.1 kg of magnesium was collected (a large amount could not be collected). Due to the significant loss of tantalum powder and its high impurity content, the performance of the tantalum powder product after subsequent processing was poor (see Table 2). Furthermore, only a small portion of the excess magnesium powder was recovered, resulting in resource waste.

[0136] Table 2 Electrical performance data of finished tantalum powder

[0137] According to Table 2, the tantalum powder prepared in the examples has better performance than that in the comparative examples.

[0138] Since the weight of excess magnesium added during the magnesium reduction of tantalum oxide to prepare tantalum powder is 10 to 30 times that of excess magnesium during the magnesium reduction and deoxygenation of tantalum powder, the tantalum powder preparation apparatus and method provided in this embodiment of the invention can effectively capture the excess magnesium remaining in the material by suction and discharge of magnesium after the magnesium reduction of tantalum oxide reaction, thereby significantly reducing the magnesium content in the final tantalum powder product and improving the purity and performance stability of tantalum powder.

[0139] Based on the various embodiments of the present invention described above, in the absence of explicit denial or conflict, the technical features of one embodiment may be advantageously combined with one or more other embodiments.

[0140] While specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the invention. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A tantalum powder production apparatus characterized by comprising: The application relates to a tantalum powder preparation method and a device thereof. The device comprises a reaction container (1) provided with a vessel (11) for containing material for preparing tantalum powder, wherein the material comprises tantalum oxide and magnesium powder; and a collector (2) arranged in the reaction container (1), wherein the collector (2) comprises a top wall (21), a bottom wall (22) and a circumferential side wall (23) connecting the top wall (21) and the bottom wall (22), the bottom wall (22) covers the upper portion of the vessel (11) and is provided with a plurality of first through holes, the top wall (21) is provided with a second through hole communicated with an evacuation pipeline (3), and the collector (2) is configured to collect magnesium vapor entering the collector (2) through the plurality of first through holes. The cross section of the collector (2) is trapezoidal, and the area of the top wall (21) is smaller than that of the bottom wall (22).

2. The tantalum powder production apparatus according to claim 1, characterized by The bottom wall (22) is located at a position 20-40 cm above the vessel (11).

3. The tantalum powder production apparatus of claim 1, wherein The device further comprises a cooling assembly (4) arranged at the outer periphery of the reaction container (1) and located at a position corresponding to the collector (2).

4. The tantalum powder production apparatus of claim 1, wherein The device further comprises the evacuation pipeline (3) penetrating through a top cover (13) of the reaction container (1) and communicated with the second through hole. The evacuation pipeline (3) is configured to evacuate and discharge magnesium for 3-20 hours after the reaction of the material.

5. The tantalum powder production apparatus of claim 1, wherein The evacuation pipeline (3) is configured to have an evacuation pressure of -0.1 MPa to -0.05 MPa. The device further comprises a heating assembly (5) arranged outside the reaction container (1) and configured to heat the material, wherein the heating assembly (5) is configured to control the temperature of the material to be 650-850 DEG C after the reaction of the material.

6. The tantalum powder production apparatus according to claim 5, wherein The device further comprises a heating assembly (5) arranged outside the reaction container (1), and the heating assembly (5) is configured to control the temperature of the material to be 850-1000 DEG C during the reaction of the material.

7. The tantalum powder production apparatus of claim 6, wherein The collector (2) is made of a nickel-based alloy material.

8. The tantalum powder production apparatus of claim 6, wherein The tantalum powder preparation method comprises the following steps: S10, placing the material for preparing tantalum powder in the vessel (11) in the reaction container (1) and making the material undergo a reduction reaction to prepare tantalum powder, wherein the material comprises tantalum oxide and magnesium powder; and 9. The tantalum powder production apparatus of claim 1, wherein S20, collecting the magnesium vapor in the reaction container (1) by the collector (2) after the reduction reaction of the material is completed. In step S20, after the reduction reaction of the material is completed, the temperature of the material is controlled to be 650-850 DEG C, and then the magnesium vapor in the reaction container (1) is collected by the collector (2).

10. The tantalum powder production apparatus of claim 1, wherein In step S20, the evacuation pipeline (3) is provided with suction force to make the magnesium vapor enter the collector (2), and the evacuation and magnesium discharge time of the evacuation pipeline (3) is controlled to be 3-20 hours to make the collector (2) collect the magnesium vapor in the reaction container (1).

11. A method for producing tantalum powder using the tantalum powder production apparatus according to any one of claims 1 to 10, wherein In step S20, the evacuation pressure in the evacuation pipeline (3) is -0.1 MPa to -0.05 MPa. ​ ​ 12. The method of claim 11, wherein the tantalum powder is prepared by a process comprising: ​ 13. The method of claim 12, wherein the tantalum powder is prepared by a process comprising: ​ 14. The method of claim 13, wherein the tantalum powder is prepared by the steps of: ​ ​ 15. The method of claim 11, wherein the tantalum powder is prepared by the steps of: In the step S10, the material temperature is controlled to be 850-1000 ℃, the temperature is kept for 1-10 h, and the pressure in the reaction container (1) is controlled to be 0.1-0.15 MPa, so that the material is subjected to a reduction reaction to prepare tantalum powder. ​

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