Method for preparing high-purity manganese by using high and low vacuum

Abstract

The invention relates to the technical field of high-purity manganese preparation, and discloses a high-purity manganese preparation method using high and low vacuum, which comprises the following steps: S0, pretreatment operation: before pickling operation, carrying out mechanical polishing or sand blasting treatment on a manganese sheet to remove oxides and impurity layers on the surface; the method comprises the following steps: S1, pickling operation: carrying out pickling on a manganese sheet with the purity of 2N by using 0.5-10% dilute sulfuric acid under an ultrasonic condition through cleaning equipment; s2, washing and drying: washing the manganese sheet subjected to acid washing in the step S1 with pure water through cleaning equipment under an ultrasonic condition, and transferring the manganese sheet into a vacuum drying oven for drying after the pure water washing is completed; and S3, high-vacuum smelting is conducted, specifically, manganese sheets obtained through washing and drying in the step S2 are loaded into a suspension smelting furnace, smelting is conducted under the high-vacuum condition, high-purity hydrogen is introduced, the manganese solution is subjected to hydrogen treatment, and oxides and hydrides which are difficult to volatilize are removed. High-purity hydrogen is introduced for treatment under a high-vacuum condition, and a low-vacuum pulling technology is combined, so that impurities are effectively removed, and the purity of a finished product is improved.

Description

Technical Field

[0001] The invention relates to the technical field of high-purity manganese preparation, and in particular to a method for preparing high-purity manganese by utilizing high and low vacuum. Background Art

[0002] As a key material, high-purity manganese is widely used in high-tech fields such as electronics, aerospace, and special alloys, especially in the preparation of high-performance electromagnetic materials, magnetic alloys, and electronic devices. However, the existing manganese purification process has some problems and it is difficult to meet the demand for extremely high-purity manganese.

[0003] Traditional methods of manganese purification usually rely on electrolysis and chemical metallurgy, but these processes have obvious limitations. First, the electrolysis method is less efficient in removing impurities, especially for non-metallic impurities such as oxides and hydrides, resulting in the purity of the obtained manganese usually remaining at around 2N (99%). Secondly, although the high-temperature smelting process in the metallurgical method can effectively remove some metal impurities, it is easy to introduce secondary pollution in the process, making it difficult to significantly improve the purity of the final product. At the same time, in terms of crystal structure control, traditional processes often have the problem of difficult to effectively eliminate thermal stress, which makes it easy for cracks and defects to appear inside the crystal, affecting the quality of the material.

[0004] In addition, due to the lack of effective physical enhancement methods, the existing pickling and pure water cleaning processes make it difficult to completely remove oxides and impurities during the cleaning process, especially trace impurities are prone to remain on the surface of manganese sheets, affecting the effects of subsequent smelting and purification processes.

[0005] In order to meet the demand for ultra-high purity manganese materials in the field of high-end technology, it is urgent to develop a more efficient preparation process that can remove metal and non-metallic impurities while ensuring the structural integrity and high purity of manganese single crystals, while improving production efficiency and adapting to large-scale industrial production. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention provides a method for preparing high-purity manganese using high and low vacuum, which solves the problem in the prior art that it is difficult to effectively remove non-metallic impurities such as oxides and hydrides, resulting in insufficient manganese purity and incomplete crystal structure.

[0007] To achieve the above objectives, the present invention is implemented by the following technical solutions: A method for preparing high-purity manganese using high and low vacuum, comprising:

[0008] S1. Pickling operation: pickling the manganese sheet with a purity of 2N with 0.5-10% dilute sulfuric acid under ultrasonic conditions through a cleaning device;

[0009] S2, water washing and drying: the manganese sheet after the acid washing in step S1 is washed with pure water by a cleaning device under ultrasonic conditions, and after the pure water washing is completed, it is transferred to a vacuum oven for drying;

[0010] S3, high vacuum smelting: the manganese flakes obtained by washing and drying in step S2 are placed into a suspension smelting furnace and smelted under high vacuum conditions;

[0011] S4, low vacuum pulling: after the high vacuum melting in step S3, the vacuum degree of the suspension melting furnace is adjusted to low vacuum, and the manganese solution is pulled by a seeding rod to purify it in a manner of pulling single crystals to obtain high-purity manganese with a purity of 5N;

[0012] The following steps are also included:

[0013] S0. Pretreatment: Before pickling, the manganese sheet is mechanically polished or sandblasted to remove the surface oxide and impurity layer;

[0014] While performing high vacuum melting in step S3, high-purity hydrogen is introduced to treat the manganese solution with hydrogen to remove oxides and hydrides that are difficult to volatilize.

[0015] Preferably, the mechanical polishing or sandblasting in step S0 makes the surface roughness of the manganese sheet reach Ra≤1 μm, thereby improving the uniformity and efficiency of subsequent pickling.

[0016] Preferably, the pickling in step S1 is performed under an ultrasonic frequency of 20-40 kHz, and the pickling time is 10-30 minutes.

[0017] Preferably, the vacuum drying in step S2 is carried out at a temperature of 80-120° C. and a vacuum degree of 0.1-10 Pa, and the drying time is 1-3 hours.

[0018] Preferably, the purity of the high-purity hydrogen in step S3 is not less than 99.999%, the hydrogen introduction rate is 10-50 ml / min, and the hydrogen treatment time is 30-120 minutes.

[0019] Preferably, the pulling speed in step S4 is 0.5-5 mm / h, and the melt temperature is kept constant at 5-20° C. above the melting point of manganese during the pulling process.

[0020] Preferably, the segmented cooling in step S5 is carried out by lowering the temperature by 10-30°C per hour until the room temperature, and the temperature gradient is controlled not to exceed 5°C / cm during the cooling process.

[0021] Preferably, the cleaning equipment used in steps S1 to S2 includes a cleaning box, which is provided with a circular groove for placing different cleaning liquids, an ultrasonic generator is provided at a position corresponding to the circular groove at the lower part of the cleaning box, a cleaning mechanism is provided in the circular groove, a notch is connected between the two circular grooves, a discharge port is provided on the circular groove on the left, the bottom wall of the inner cavity of the circular groove is an inclined surface inclined toward the rear side, and a drain pipe is connected to the rear end surface of the cleaning box at a position corresponding to the circular groove one by one, and a drain valve is installed on the drain pipe.

[0022] Preferably, the cleaning mechanism comprises a top plate, the top plate is installed on the upper end surface of the cleaning box, a No. 1 screw is rotatably installed between the top plate and the bottom wall of the circular groove, a sliding tube is slidably installed on the No. 1 screw, a circular mesh plate is installed on the lower end of the sliding tube through an adjusting member, a compression spring is installed between the upper end surface of the sliding tube and the top plate, a No. 1 telescopic tube connected to the sliding tube and the top plate is sleeved on the outer side of the compression spring, a stirring member is arranged below the circular mesh plate, the stirring member comprises a screw sleeve, a screw sleeve is installed on the lower end surface of the sliding tube in cooperation with the screw thread, the lower part of the screw sleeve is rotatably inserted through the circular mesh plate, and a stirring plate is evenly installed on the circumferential outer wall of the screw sleeve along its circumference;

[0023] The adjusting member includes a first compression spring, a second compression spring is installed between the lower end surface of the sliding tube and the circular mesh plate, and the outer side of the first compression spring is sleeved with a second expansion tube connected to the sliding tube and the circular mesh plate, and a cross rod is slidably installed on the sliding tube, and the lower end of the cross rod is hinged with the circular mesh plate, and the horizontal section of the cross rod on the left side conflicts with the lower end surface of the sliding tube, and the horizontal section of the cross rod on the right side conflicts with the upper end surface of the sliding tube. A driving member for driving the sliding tube to move is arranged on the top plate. The driving member includes a rope, and a rope is symmetrically installed on the front and rear ends of the upper end surface of the sliding tube. The upper end of the rope slides through the top plate through a support and is rotated by a guide wheel on the top plate, and a rotating shaft is rotated by an axle seat to install a guide wheel at a position corresponding to the rope. The position of the rotating shaft corresponding to the rope is installed, and the rope is fixedly connected to the retractable wheel after passing the corresponding guide wheel. An actuator for driving the two rotating shafts to rotate synchronously is arranged on the top plate.

[0024] The actuator includes a synchronous belt. The front ends of the two rotating shafts are connected through a synchronous belt transmission. A No. 2 screw is rotatably installed on the top plate through the shaft plate. An incomplete gear is fixedly installed on the No. 2 screw. A spur gear is installed at the rear end of the right rotating shaft. The spur gear is meshed with the incomplete gear. A slide groove is provided in the toothless section of the incomplete gear. A fan-shaped plate is slidably installed in the slide groove through a tension spring. The arc surface of the fan-shaped plate is evenly installed with teeth. A pushing piece for pushing the fan-shaped plate to move is provided on the No. 2 screw.

[0025] Preferably, the pushing member includes a rectangular groove, a rectangular groove is connected to the slide groove position on the front end surface of the incomplete gear, an inclined block is installed on the front end surface of the fan-shaped plate, and the inclined block is in a right-angled triangle structure. A support plate is installed on the rectangular groove position on the front end surface of the incomplete gear through a No. 2 compression spring, and a pushing block is installed on the end surface of the support plate close to the inclined block, and the surface of the pushing block in contact with the inclined block is an inclined surface, and a ball is evenly rolled on the end surface of the support plate away from the incomplete gear, a pressure plate is slidably installed on the No. 2 screw rod, a limiting rod is installed between the two shaft plates, the pressure plate is slidably installed on the limiting rod, and a guide column is slidably installed on the pressure plate through a No. 3 compression spring, and a group of guide components are respectively arranged at the positions corresponding to the circular grooves on the cleaning box, and each group of guide components consists of two flow channels symmetrical front and rear, and the upper and lower ports of the flow channel are connected to the corresponding circular grooves.

[0026] The present invention provides a method for preparing high-purity manganese using high and low vacuum. It has the following beneficial effects:

[0027] 1. The present invention effectively removes impurities by introducing high-purity hydrogen and treating under high vacuum conditions, combining low-vacuum pulling technology, so that the purity of the final manganese single crystal reaches 99.999%.

[0028] 2. The present invention adopts an ultrasonic frequency of 20-40kHz, combined with mechanical stirring, to make the pickling process more efficient, thoroughly remove oxides and impurities on the surface of the manganese sheet, and improve the overall process effect.

[0029] 3. The present invention effectively reduces the thermal stress in the crystal and avoids structural defects through segmented cooling and low vacuum pulling, thus ensuring that the manganese single crystal has excellent mechanical strength and stability.

[0030] 4. The dual effects of ultrasonic wave and stirring of the cleaning equipment of the present invention ensure uniform and rapid processing of manganese flakes during the cleaning process, improve the cleaning quality, and further ensure the effect of the subsequent smelting step. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a flow chart of the present invention;

[0032] Figure 2 It is a schematic diagram of the three-dimensional structure from a first viewing angle of the present invention;

[0033] Figure 3 is a schematic diagram of a second viewing angle stereoscopic structure of the present invention;

[0034] Figure 4 for Figure 3 Enlarged view of point A in the middle;

[0035] Figure 5 It is a schematic diagram of the structure between the flow channel and the circular groove of the present invention;

[0036] Figure 6is a cross-sectional view of the present invention;

[0037] Figure 7 for Figure 6 Enlarged view of point B in the middle;

[0038] Figure 8 A partial structural cross-sectional view of an actuator of the present invention;

[0039] Fig. 9 It is a partial cross-sectional view of the push member of the present invention.

[0040] Among them, 10, cleaning box; 11, round groove; 110, flow channel; 12, notch; 13, discharge port; 14, drain pipe; 2, cleaning mechanism; 20, top plate; 21, No. 1 screw rod; 22, slide pipe; 23, round mesh plate; 24, compression spring; 25, No. 1 telescopic tube; 26, adjustment part; 260, No. 1 compression spring; 261, No. 2 telescopic tube; 262, cross rod; 27, stirring part; 270, screw sleeve; 271, stirring Plate; 28, driving member; 280, rope; 281, guide wheel; 282, rotating shaft; 283, retracting and releasing wheel; 3, actuator; 30, synchronous belt; 31, No. 2 screw rod; 32, incomplete gear; 33, spur gear; 34, fan-shaped plate; 35, teeth; 4, pushing member; 40, rectangular groove; 41, inclined block; 42, No. 2 compression spring; 43, support plate; 44, pushing block; 45, pressure plate; 46, limit rod; 47, guide column. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Embodiment 1:

[0043] Please see attached Figure 1 The embodiment of the present invention provides a method for preparing high-purity manganese using high and low vacuum, comprising the following steps:

[0044] S0, pre-processing operation:

[0045] In this embodiment, before the pickling operation, the manganese sheet with a purity of 2N is mechanically polished or sandblasted. Specifically, the surface of the manganese sheet is mechanically polished using precision polishing equipment until the surface roughness reaches Ra≤1μm; or, the manganese sheet is sandblasted using sandblasting equipment by adjusting the sandblasting pressure and abrasive particle size, so that the surface roughness reaches Ra≤1μm.

[0046] The purpose of this step is to remove the oxide and impurity layer on the surface of the manganese sheet, increase the surface finish, and improve the uniformity and efficiency of subsequent pickling. The surface of the pretreated manganese sheet is clean and flat, which is conducive to the full contact and reaction between the acid and the metal surface.

[0047] S1. Pickling operation:

[0048] In this embodiment, the pretreated manganese sheet is placed in a specially designed cleaning device and pickled with a dilute sulfuric acid solution with a concentration of 0.5-10%. During the pickling process, the ultrasonic generator set in the cleaning device operates at a frequency of 20-40kHz, and the pickling time is controlled to be 10-30 minutes.

[0049] The specific operation is as follows: the manganese sheet is placed on the circular mesh plate 23 of the cleaning mechanism 2, and the cleaning mechanism can move up and down in the acid solution. The cavitation effect of the ultrasonic wave causes the acid solution to form a tiny impact on the surface of the manganese sheet, which enhances the acid solution's ability to dissolve and strip oxides and impurities. At the same time, the stirring member 27 of the cleaning mechanism produces a stirring effect in the acid solution, promoting the flow and renewal of the acid solution, and ensuring the uniformity and adequacy of the pickling.

[0050] This step effectively removes residual oxides, oil stains and other impurities on the surface of the manganese flakes, laying a good foundation for the subsequent purification process.

[0051] S2, washing and drying:

[0052] After the pickling is completed, the manganese sheet is directly transferred to the pure water cleaning tank through the notch 12 in the cleaning equipment to avoid re-oxidation due to exposure to air in the middle. In this embodiment, the pure water cleaning is also carried out under ultrasonic conditions with a frequency of 20-40kHz, and the cleaning time is adjusted according to the actual situation until the surface of the manganese sheet is free of acid residue.

[0053] The purpose of pure water cleaning is to completely remove the acid and soluble impurities on the surface of the manganese sheet after pickling to prevent the residual acid from corroding the manganese sheet. After cleaning, the manganese sheet is taken out through the discharge port 13 of the cleaning equipment and transferred to a vacuum oven for drying.

[0054] The drying process is carried out at a temperature of 80-120°C and a vacuum degree of 0.1-10Pa for 1-3 hours. Vacuum drying can quickly remove moisture and insoluble particles on the surface of the manganese flakes and prevent the manganese flakes from reacting with oxygen in the air at high temperatures and being oxidized again.

[0055] S3, High Vacuum Melting and Hydrogen Treatment:

[0056] In this embodiment, the dried manganese flakes are loaded into a suspension smelting furnace and smelted under high vacuum conditions with a vacuum degree better than 1×10^-3 Pa. At the same time, high-purity hydrogen with a purity of not less than 99.999% is introduced, the hydrogen introduction rate is 10-50 ml / min, and the hydrogen treatment time is 30-120 minutes.

[0057] The smelting temperature is controlled at 5-20℃ above the melting point of manganese, about 1246℃, to ensure that manganese is fully melted without excessive evaporation. Hydrogen reacts with oxides and hydrides in the manganese solution at high temperature to generate volatile substances such as water vapor and hydrogen, which are quickly extracted under high vacuum conditions, thereby effectively removing non-volatile impurities in manganese.

[0058] The design of the suspension smelting furnace prevents the molten manganese from contacting any container material, thus avoiding the secondary introduction of impurities. The combination of high vacuum and hydrogen treatment greatly improves the purity of manganese and reduces the content of impurity elements.

[0059] S4, low vacuum pulling:

[0060] After completing high vacuum melting and hydrogen treatment, the vacuum degree of the suspension melting furnace is adjusted to a low vacuum condition with a vacuum degree of 1-10 Pa. In this embodiment, a seeding rod is used to pull a manganese single crystal from a molten manganese solution at a speed of 0.5-5 mm / h.

[0061] During the pulling process, the melt temperature is kept constant at 5-20°C above the melting point of manganese. By controlling the pulling speed and temperature gradient, manganese gradually solidifies at the solid-liquid interface to form a single crystal structure. Due to the different distribution coefficients of impurity elements in the solid phase and the liquid phase, impurities tend to remain in the liquid phase. Therefore, during the pulling process, impurities are gradually removed and the purity of manganese is further improved.

[0062] Under low vacuum conditions, the evaporation rate of molten manganese is reduced, which is conducive to stabilizing the crystal growth environment and improving the quality of single crystals.

[0063] S5, staged cooling:

[0064] After the pulling is completed, the obtained high-purity manganese single crystal needs to be gradually cooled to room temperature. In this embodiment, a segmented cooling method is adopted, the temperature is reduced by 10-30°C per hour, and the temperature gradient is controlled not to exceed 5°C / cm during the cooling process.

[0065] Segmented cooling can effectively reduce the thermal stress in the crystal and prevent cracks and structural defects in the crystal. By precisely controlling the cooling rate and temperature gradient, the integrity and stability of the manganese single crystal are ensured, and the product quality is improved.

[0066] The specific cleaning equipment is used to ensure efficient and uniform cleaning effect during the cleaning process of manganese flakes. The design focus of the cleaning equipment is on the efficiency and controllability of the cleaning process, especially in the acid cleaning and pure water cleaning steps, ultrasonic and stirring are used to effectively remove oxides and impurities on the surface of manganese flakes to ensure the cleaning quality.

[0067] In the present invention, the cleaning equipment includes a cleaning box 10, which is designed to carry two separated circular grooves 11 of acid cleaning liquid and pure water cleaning liquid, each of which is used for storage and circulation cleaning operation of different cleaning media. The design of the cleaning box is compact and easy to operate, while providing sufficient cleaning space and liquid storage capacity for subsequent operations.

[0068] As shown in the figure, ultrasonic generators (not shown) are arranged at the lower part of the cleaning box 10 and at the position of each circular groove 11. The ultrasonic generator generates high-frequency vibrations during the cleaning process, and utilizes the cavitation effect of ultrasonic waves to accelerate the flow and cleaning efficiency of acid or pure water, and can effectively remove oxides, impurities and residual acidic substances on the surface of the manganese sheet. A cleaning mechanism 2 is respectively arranged in the two circular grooves 11, and the cleaning mechanism is responsible for the up and down movement and stirring of the manganese sheet.

[0069] The two circular grooves 11 are interconnected through the middle notch 12, which facilitates the conversion of the manganese flakes between the pickling solution and the pure water cleaning solution during the cleaning process. A discharge port 13 is provided on the circular groove 11 on the left side so that the manganese flakes can be transferred to an external drying device for drying after the cleaning is completed. The bottom wall of the circular groove 11 is designed as an inclined surface inclined to the rear side so that the liquid and deposited impurities can be discharged smoothly during the drainage process. In order to achieve regular discharge and replacement of the liquid, a drain pipe 14 is connected to the rear end face of the cleaning box 10 at a position corresponding to the circular groove 11, and a drain valve (not shown) is installed on the drain pipe for discharging waste liquid.

[0070] like Figure 2 , Figure 3 and Figure 6 As shown, the key parts of the cleaning mechanism 2 are the top plate 20 and the first screw 21. The top plate 20 is installed on the upper end surface of the cleaning box 10, and the top plate is connected to the bottom wall of the circular groove 11 through the first screw 21 that is rotatably installed. A slide tube 22 is slidably installed on the first screw 21, and the lower end of the slide tube is connected to the circular mesh plate 23 through an adjusting member 26, and the circular mesh plate is used to carry the manganese flakes being cleaned.

[0071] During operation, the up and down movement of the slide tube 22 is controlled by the No. 1 screw rod 21. A compression spring 24 is installed between the upper end of the slide tube and the top plate 20. When the slide tube 22 rises, the compression spring is compressed to provide a rebound force. A No. 1 telescopic tube 25 is sleeved on the outside of the compression spring to protect the compression spring and ensure the smooth movement of the slide tube. When the slide tube moves downward, the manganese sheet will be pushed downward into the cleaning liquid through the circular mesh plate 23, and at the same time, the ultrasonic wave is cooperated to ensure that the manganese sheet is fully in contact with the cleaning liquid.

[0072] A stirring member 27 is also installed below the circular mesh plate 23, and the stirring member includes a screw sleeve 270 and a stirring plate 271. During the cleaning process, the stirring member cooperates with the sliding pipe thread through the screw sleeve, so that when the sliding pipe moves, the stirring plate can generate a rotating stirring effect in the cleaning liquid, thereby enhancing the fluidity of the cleaning liquid and ensuring the uniformity of cleaning.

[0073] The driving device 28 of the cleaning device is as follows Figure 2 , Figure 3 and Figure 6 As shown, it mainly includes a rope 280, a guide wheel 281, a retractable wheel 283 and a rotating shaft 282. The rope 280 is symmetrically installed on the upper end surface of the slide tube 22. The rope slides through the top plate 20, passes around the guide wheel 281 and is connected to the retractable wheel 283. The rotating shaft 282 is connected to the actuator 3 through a synchronous belt 30 to ensure that the two rotating shafts can rotate synchronously, thereby driving the slide tube to move up and down.

[0074] The driving device is responsible for controlling the lifting and lowering of the slide tube 22, ensuring that the manganese sheet can move up and down in the cleaning liquid at an appropriate speed during the cleaning process, increasing the contact frequency between the cleaning liquid and the surface of the manganese sheet. At the same time, the retracting wheel 283 can flexibly adjust the length of the rope to control the movement range of the circular mesh plate 23.

[0075] like Figure 3 , Figure 4 , Figure 8 and Fig. 9 As shown, the actuator 3 is used to accurately control the movement of the circular screen 23. The actuator is connected to the two shafts 282 through a synchronous belt 30, and the rotation of the shaft is transmitted to the second screw 31 through the synchronous belt. An incomplete gear 32 is fixedly installed on the second screw, and the toothless section of the gear cooperates with the spur gear 33. When the second screw rotates, the gear drives the spur gear to rotate synchronously, so that the slide tube moves up.

[0076] The incomplete gear 32 is provided with a slide groove, in which a sector plate 34 is slidably installed, and teeth 35 are evenly installed on the arc surface of the sector plate, so as to realize accurate mesh plate movement in coordination with the movement of the gear. The slide groove cooperates with the sector plate through a tension spring, and when the tension spring is stressed, the sector plate is pushed to move along the slide groove to adjust the position of the circular mesh plate.

[0077] The role of the push member 4 in the actuator is shown in the figure. It can push the teeth out of or into the gear meshing position at a specific stage in the cleaning process to ensure that the manganese sheet moves smoothly during the cleaning and transfer process.

[0078] Pickling process: First, the operator adds pure water to the left circular groove 11, and acid to the right circular groove 11, and puts the manganese sheets into the acid in turn. At this time, the circular mesh plate 23 is located at the bottom of the acid tank, and the manganese sheets will slowly fall onto the mesh plate. During the pickling process, the drive device drives the circular mesh plate to move up slowly, so that the manganese sheets are evenly affected by the ultrasonic wave and acid in the acid. At the same time, the rotation of the stirring element ensures that the acid flows on the surface of the manganese sheet to avoid dead corners.

[0079] Pure water cleaning: After the pickling is completed, the driving device lifts the circular screen plate 23 to the position of the pure water cleaning tank 11, and smoothly moves the manganese sheet into the pure water tank through the notch 12. At this time, the screen plate moves up and down again, and the pure water is used to clean the acid and impurities remaining on the surface of the manganese sheet.

[0080] Drying: After cleaning, the manganese flakes are transferred to an external drying device for drying through the discharge port 13. At this point, the manganese flakes have been thoroughly cleaned and are ready to enter the subsequent smelting and pulling steps.

[0081] Liquid replacement: During the cleaning process, the acid and pure water will gradually become saturated with impurities, so the cleaning liquid needs to be replaced regularly. By opening the drain valve on the drain pipe 14, the waste liquid can be smoothly discharged from the circular groove, and the residual sediment in the cleaning box can be naturally discharged through the inclined design.

[0082] The cleaning equipment provided in this embodiment provides technical support for the key links in the preparation process of high-purity manganese. Through ultrasonic cleaning, mechanical stirring and precisely controlled mesh plate movement, the equipment can achieve efficient and uniform cleaning of manganese flakes, improving the efficiency of the entire preparation process and product quality. The equipment has a reasonable structural design and is easy to operate, which can meet the needs of large-scale industrial production and ensure the high purity and cleanliness of manganese flakes.

[0083] Embodiment 2:

[0084] This embodiment provides a method for preparing high-purity manganese using high and low vacuum. The main difference from the first embodiment is that the frequency of the ultrasonic wave during the pickling process is different, which is used to verify that the pickling process in the first embodiment is optimal. Specifically, the following steps are included:

[0085] S0, pre-processing operation:

[0086] The pretreatment operation of this embodiment is the same as that of the first embodiment. The manganese sheet with a purity of 2N is mechanically polished or sandblasted to ensure that the surface roughness of the manganese sheet reaches Ra≤1μm. After the pretreatment, the oxide and impurity layer on the surface of the manganese sheet are removed, which improves the efficiency and uniformity of the subsequent pickling.

[0087] S1. Pickling operation:

[0088] The difference from Example 1 is that the ultrasonic frequency in the pickling process of this embodiment is set to 10-20kHz, instead of 20-40kHz in Example 1. This frequency is still used to generate the cavitation effect of the ultrasonic wave, promoting the removal of oxides and impurities on the surface of the manganese sheet by the acid solution. The specific conditions of pickling are as follows:

[0089] Acid concentration: 0.5-10% dilute sulfuric acid solution;

[0090] Pickling time: 15 minutes.

[0091] The specific operation process is the same as that of the first embodiment. The manganese sheet is placed on the circular screen plate (23) of the cleaning mechanism (2). The screen plate moves up and down in the pickling liquid. The ultrasonic cavitation effect and the mechanical action of the stirring element make the acid liquid flow fully, ensuring the uniformity of cleaning.

[0092] S2, washing and drying:

[0093] After the pickling is completed, the manganese sheet is directly transferred to the pure water cleaning tank through the notch (12) of the cleaning equipment to prevent the manganese sheet from being exposed to the air and oxidized again. As in Example 1, the pure water cleaning in this example is carried out under the condition of an ultrasonic frequency of 10-20kHz, the purpose of which is to completely remove the residual acid and impurities on the surface of the manganese sheet. After the pure water cleaning, the manganese sheet is taken out and transferred to a vacuum oven for drying. The specific conditions are:

[0094] Drying temperature: 80-120℃;

[0095] Vacuum degree: 0.1-10Pa;

[0096] Drying time: 1-3 hours.

[0097] Vacuum drying can effectively remove moisture and insoluble particles on the surface of manganese flakes and prevent oxidation reactions.

[0098] S3, High Vacuum Melting and Hydrogen Treatment:

[0099] This embodiment is the same as the first embodiment, the dried manganese flakes are loaded into a suspension smelting furnace and smelted under high vacuum conditions. During the smelting process, high-purity hydrogen with a purity of not less than 99.999% is introduced to remove oxides and hydrides in the manganese solution. The specific conditions are as follows:

[0100] Vacuum degree: better than 1×10^-3Pa;

[0101] Melting temperature: 5-20℃ above the melting point of manganese;

[0102] Hydrogen flow rate: 10-50ml / min;

[0103] Hydrogen treatment time: 30-120 minutes.

[0104] Under the combined action of high vacuum and high-temperature hydrogen, the non-volatile impurities in the manganese solution are effectively removed, ensuring that the purity of the molten manganese reaches a high level.

[0105] S4, low vacuum pulling:

[0106] After completing high vacuum melting and hydrogen treatment, the vacuum degree of the suspension melting furnace is adjusted to 1-10Pa, and the manganese single crystal is pulled at a speed of 0.5-5mm / h by the seeding rod. During the pulling process, the melt temperature is kept constant at 5-20℃ above the melting point of manganese. Due to the segregation effect of impurities at the solid-liquid interface, the purity of manganese is further improved during the pulling process.

[0107] S5, staged cooling:

[0108] As in Example 1, after the pulling is completed, the manganese single crystal needs to be gradually cooled to room temperature. The segmented cooling method is adopted, the temperature is reduced by 10-30°C per hour, and the temperature gradient is controlled not to exceed 5°C / cm. This cooling method effectively reduces the thermal stress in the crystal and avoids the generation of crystal cracks and defects.

[0109] Compared with Example 1, the frequency of ultrasound in the pickling process of this embodiment is reduced from 20-40kHz to 10-20kHz. The experimental results show that although the lower ultrasonic frequency can still produce cavitation effect, the removal effect of oxides and impurities is relatively slow. After pickling, there is still a small amount of oxides remaining on the surface of the manganese sheet, and the smoothness after cleaning in Example 1 cannot be achieved. Therefore, the pickling efficiency and effect of this embodiment are obviously not as good as those of Example 1, especially in the subsequent steps of pulling single crystals, the purity of manganese is reduced, and the impurity content in the crystal is high.

[0110] By comparing the present embodiment, it is proved that the pickling condition with an ultrasonic frequency of 20-40 kHz in the first embodiment is optimal, which can effectively remove oxides and impurities on the surface of the manganese sheet and ensure the most ideal preparation process of high-purity manganese.

[0111] In Example 2, only the ultrasonic frequency of the pickling step is changed, which proves that in the present technical solution, the pickling process with an ultrasonic frequency of 20-40kHz is more efficient in removing impurities. In contrast, the pickling process with a frequency of 10-20kHz has a poor effect and cannot achieve the same cleaning effect. Therefore, the process method in Example 1 is the best choice, ensuring the efficient preparation of high-purity manganese.

[0112] Embodiment three:

[0113] This embodiment provides a method for preparing high-purity manganese using high and low vacuum. Except for changing the purity of hydrogen in the hydrogen treatment process, the other steps are the same as those in the first embodiment. Through this change, the effect of the hydrogen treatment step of the first embodiment on the removal of impurities is verified, and it is proved that the hydrogen purity condition of the first embodiment is optimal. Specifically, the following steps are included:

[0114] S0, pre-processing operation:

[0115] The pretreatment operation of this embodiment is the same as that of the first embodiment. The manganese sheet with a purity of 2N is treated by mechanical polishing or sandblasting to make its surface roughness reach Ra≤1μm. This step effectively removes oxides and impurities on the surface of the manganese sheet, and improves the uniformity and efficiency of subsequent pickling.

[0116] S1. Pickling operation:

[0117] The pickling operation is the same as that in Example 1. The pretreated manganese sheet is placed in a cleaning device and pickled with a dilute sulfuric acid solution having a concentration of 0.5-10%, an ultrasonic frequency of 20-40kHz, and a pickling time of 10-30 minutes. The cavitation effect of the ultrasonic wave and the mechanical action of the stirring element allow the acid solution to fully contact the surface of the manganese sheet to remove oxides and impurities.

[0118] S2, washing and drying:

[0119] After pickling, the manganese sheet is transferred to a pure water cleaning tank, where it is cleaned with pure water at an ultrasonic frequency of 20-40kHz to completely remove the acid residue, and then transferred to a vacuum oven for drying. The specific conditions are:

[0120] Drying temperature: 80-120℃;

[0121] Vacuum degree: 0.1-10Pa;

[0122] Drying time: 1-3 hours.

[0123] This step effectively removes moisture and residual impurities on the surface of the manganese sheet, preventing subsequent oxidation.

[0124] S3, High Vacuum Melting and Hydrogen Treatment:

[0125] The difference from Example 1 is that this example uses 99.9% pure hydrogen instead of 99.999% high-purity hydrogen in Example 1. The amount of hydrogen introduced and the hydrogen treatment time remain unchanged, and the specific conditions are as follows:

[0126] Vacuum degree: better than 1×10^-3Pa;

[0127] Melting temperature: 5-20℃ above the melting point of manganese;

[0128] Hydrogen flow rate: 10-50ml / min;

[0129] Hydrogen treatment time: 30-120 minutes.

[0130] During the smelting process, hydrogen is used to remove oxides and hydrides in the manganese solution. Since the hydrogen used in this embodiment is of low purity, a small amount of impurities remaining in the hydrogen may react with elements in the manganese solution, resulting in some impurities being unable to be effectively removed.

[0131] S4, low vacuum pulling:

[0132] After high vacuum melting and hydrogen treatment, the vacuum degree is adjusted to 1-10Pa, and the manganese single crystal is pulled at a speed of 0.5-5mm / h by the seeding rod. During the pulling process, the melt temperature is kept 5-20℃ above the melting point of manganese, and the pulling speed and temperature gradient are controlled to reduce the impurity content in the crystal.

[0133] S5, staged cooling:

[0134] The segmented cooling method in this embodiment is the same as that in embodiment 1. After the pulling is completed, the manganese single crystal is gradually cooled to room temperature by cooling by 10-30°C per hour, and the temperature gradient is controlled not to exceed 5°C / cm. This cooling method reduces the thermal stress in the crystal and prevents the generation of crystal cracks.

[0135] By comparison with Example 1, it can be seen that when 99.9% pure hydrogen is used for hydrogen treatment in this embodiment, although some impurities in the manganese solution can still be effectively removed, since the hydrogen contains trace impurities, these impurities are introduced into the manganese solution during the smelting process, resulting in a high impurity content in the manganese single crystal finally prepared. Specifically, in the subsequent low vacuum pulling process, the manganese single crystal pulled out has more impurities remaining and the purity is reduced.

[0136] Compared with Example 1, the hydrogen treatment effect of this example is not as good as that of using 99.999% high-purity hydrogen. Although low-purity hydrogen can provide reducing properties, it cannot completely remove oxides and hydrides in the manganese solution, resulting in the purity of the prepared high-purity manganese not meeting expectations.

[0137] By comparing with Example 3, it is proved that the process of using 99.999% high-purity hydrogen for treatment in Example 1 is the most effective. Although lower-purity hydrogen can remove impurities to a certain extent, due to its own purity problem, it will introduce trace impurities into the manganese solution, thereby affecting the purity of the final product. Therefore, the hydrogen purity condition in Example 1 is the optimal choice, ensuring the best effect of the high-purity manganese preparation process.

[0138] Table 1 Experimental data table of embodiment

[0139]

[0140]

[0141] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing high-purity manganese using high and low vacuum, comprising: S1. Pickling operation: pickling the manganese sheet with a purity of 2N with 0.5-10% dilute sulfuric acid under ultrasonic conditions through a cleaning device; S2, water washing and drying: the manganese sheet after the acid washing in step S1 is washed with pure water by a cleaning device under ultrasonic conditions, and after the pure water washing is completed, it is transferred to a vacuum oven for drying; S3, high vacuum smelting: the manganese flakes obtained by washing and drying in step S2 are placed into a suspension smelting furnace and smelted under high vacuum conditions; S4, low vacuum pulling: after the high vacuum melting in step S3, the vacuum degree of the suspension melting furnace is adjusted to low vacuum, and the manganese solution is pulled by a seeding rod to purify it in a manner of pulling single crystals to obtain high-purity manganese with a purity of 5N; It is characterized in that it also includes the following steps: S0. Pretreatment: Before pickling, the manganese sheet is mechanically polished or sandblasted to remove the surface oxide and impurity layer; While performing high vacuum melting in step S3, high-purity hydrogen is introduced to treat the manganese solution with hydrogen to remove oxides and hydrides that are difficult to volatilize.

2. The method for preparing high-purity manganese using high and low vacuum according to claim 1, characterized in that: The mechanical polishing or sandblasting in step S0 makes the surface roughness of the manganese sheet reach Ra≤1μm, thereby improving the uniformity and efficiency of subsequent pickling.

3. The method for preparing high-purity manganese using high and low vacuum according to claim 1, characterized in that: The pickling in step S1 is carried out under the condition of ultrasonic frequency of 20-40kHz, and the pickling time is 10-30 minutes.

4. The method for preparing high-purity manganese using high and low vacuum according to claim 1, characterized in that: The vacuum drying in step S2 is carried out at a temperature of 80-120° C. and a vacuum degree of 0.1-10 Pa, and the drying time is 1-3 hours.

5. The method for preparing high-purity manganese using high and low vacuum according to claim 1, characterized in that: The purity of the high-purity hydrogen in step S3 is not less than 99.999%, the amount of hydrogen introduced is 10-50 ml / min, and the hydrogen treatment time is 30-120 minutes.

6. The method for preparing high-purity manganese using high and low vacuum according to claim 1, characterized in that: The pulling speed in step S4 is 0.5-5 mm / h, and the melt temperature is kept constant at 5-20° C. above the melting point of manganese during the pulling process.

7. The method for preparing high-purity manganese using high and low vacuum according to claim 1, characterized in that: The segmented cooling in step S5 is carried out by lowering the temperature by 10-30°C per hour until the room temperature is reached, and the temperature gradient is controlled not to exceed 5°C / cm during the cooling process.

8. The method for preparing high-purity manganese using high and low vacuum according to claim 1, characterized in that: The cleaning device used in steps S1 to S2 comprises a cleaning box (10), the cleaning box is provided with a circular groove (11) for placing different cleaning liquids, an ultrasonic generator is provided at a position corresponding to the circular groove at the bottom of the cleaning box, a cleaning mechanism (2) is provided in the circular groove, a notch (12) is connected between the two circular grooves (11), a discharge port (13) is provided on the circular groove (11) on the left side, the inner cavity bottom wall of the circular groove (11) is an inclined surface inclined toward the rear side, a drain pipe (14) is connected to the rear end surface of the cleaning box (10) at a position corresponding to the circular groove (11), and a drain valve is installed on the drain pipe (14).

9. The method for preparing high-purity manganese using high and low vacuum according to claim 8, characterized in that: The cleaning mechanism (2) comprises a top plate (20), the top plate (20) is installed on the upper end surface of the cleaning box (10), a first screw rod (21) is rotatably installed between the top plate (20) and the bottom wall of the circular groove (11), a slide tube (22) is slidably installed on the first screw rod (21), a circular mesh plate (23) is installed on the lower end of the slide tube (22) through an adjusting member (26), a compression spring (24) is installed between the upper end surface of the slide tube (22) and the top plate (20), and the compression spring (24) is installed between the upper end surface of the slide tube (22) and the top plate (20), and the compression spring (24) is installed between the upper end surface of the slide tube (22) and the top plate (20). The outer side of the compression spring (24) is sleeved with a first telescopic tube (25) connected to the slide tube (22) and the top plate (20); a stirring member (27) is arranged below the circular mesh plate (23); the stirring member (27) comprises a screw sleeve (270); the lower end surface of the slide tube (22) is fitted with the screw sleeve (270) in a threaded manner; the lower part of the screw sleeve (270) rotates and penetrates the circular mesh plate (23); stirring plates (271) are evenly arranged on the circumferential outer wall of the screw sleeve (270) along its circumference; The adjusting member (26) comprises a No. 1 compression spring (260), a No. 1 compression spring (260) is installed between the lower end surface of the sliding tube (22) and the circular mesh plate (23), a No. 2 telescopic tube (261) connected to the sliding tube (22) and the circular mesh plate (23) is sleeved on the outer side of the No. 1 compression spring (260), a cross rod (262) is slidably installed on the left and right sides of the sliding tube (22), the lower end of the cross rod (262) is hinged to the circular mesh plate (23), the horizontal section of the cross rod (262) located on the left side abuts against the lower end surface of the sliding tube (22), and the horizontal section of the cross rod (262) located on the right side abuts against the upper end surface of the sliding tube (22), and a driving member (28) for driving the sliding tube (22) to move is arranged on the top plate (20), and the driving member (28) The invention comprises a rope (280), the rope (280) is symmetrically installed on the upper end face of the sliding tube (22) in the front and rear directions, the upper end of the rope (280) slides through the top plate (20), a round shaft is rotatably installed on the top plate (20) through a support, a guide wheel (281) is installed on the round shaft at a position corresponding to the rope (280), a rotating shaft (282) is rotatably installed on the upper end face of the top plate (20) at a position corresponding to the first screw rod (21) through an axle seat, a retractable wheel (283) is installed on the rotating shaft (282) at a position corresponding to the rope (280), the rope (280) is fixedly connected to the retractable wheel (283) after passing the corresponding guide wheel (281), and an actuator (3) for driving the two rotating shafts (282) to rotate synchronously is arranged on the top plate (20); The actuator (3) comprises a synchronous belt (30), the front ends of the two rotating shafts (282) are connected by the synchronous belt (30), a second screw rod (31) is rotatably mounted on the top plate (20) through the shaft plate, an incomplete gear (32) is fixedly mounted on the second screw rod (31), a spur gear (33) is mounted on the rear end of the right rotating shaft (282), the spur gear (33) is meshed with the incomplete gear (32), a sliding groove is provided in the toothless section of the incomplete gear (32), a fan-shaped plate (34) is slidably mounted in the sliding groove through the cooperation of a tension spring, teeth (35) are evenly mounted on the arc surface of the fan-shaped plate (34), and a pushing member (4) for pushing the fan-shaped plate (34) to move is provided on the second screw rod (31).

10. The method for preparing high-purity manganese using high and low vacuum according to claim 9, characterized in that: The push member (4) comprises a rectangular groove (40), the front end surface of the incomplete gear (32) is connected to the rectangular groove (40) at the position corresponding to the slide groove, the front end surface of the sector plate (34) is installed with an inclined block (41), the inclined block (41) is in a right triangle structure, the front end surface of the incomplete gear (32) is installed with a support plate (43) at the position corresponding to the rectangular groove (40) through a second compression spring (42), a pushing block (44) is installed on one end surface of the support plate (43) close to the inclined block (41), the surface of the pushing block (44) contacting the inclined block (41) is an inclined surface, and the support plate (43) is away from the incomplete gear (32). A ball bearing is evenly and rollingly mounted on one end surface of the full gear (32); a pressure plate (45) is slidably mounted on the second screw rod (31); a limit rod (46) is installed between the two shaft plates; the pressure plate (45) is slidably mounted on the limit rod (46); a guide column (47) is slidably mounted on the pressure plate (45) via a third compression spring; a group of guide assemblies are respectively arranged at positions corresponding to the circular groove (11) on the cleaning box (10); each group of guide assemblies consists of two flow channels (110) symmetrically disposed front and rear; and upper and lower ports of the flow channel (110) are connected to the corresponding circular groove (11).

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