Method for separating and obtaining high-purity metal beryllium from electrolytic cathode product

Abstract

The invention relates to a method for separating and obtaining high-purity metal beryllium from an electrolytic cathode product. The method comprises the following steps that S1, the electrolytic cathode product is smashed and dried, and a first product is obtained; wherein the first product is a mixture of metal beryllium and fluoride molten salt; s2, heating the first product to a first temperature under a vacuum condition so as to melt the fluoride molten salt therein, and applying an auxiliary electric field which enables fluoride molten salt ions in a molten state in the first product to float upwards and generate rapid disturbance; the metal beryllium particles sink to the lower layer; continuously heating to a second temperature, and carrying out vacuum distillation at the second temperature to volatilize the upper fluoride fused salt in a gaseous state and recover the upper fluoride fused salt to prepare primary metal beryllium; and S3, the primary metal beryllium is cleaned with an aluminum sulfate solution and then dried, and pure metal beryllium is obtained. The method has the beneficial effect that the separation purity and the separation efficiency for separating the metal beryllium from the electrolytic cathode product can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrolytic cathode product processing, and particularly relates to a method for separating and obtaining high-purity metallic beryllium from an electrolytic cathode product. BACKGROUND

[0002] In the process of preparing metallic beryllium by means of fluoride molten salt electrolysis, the product reduced on the cathode is usually a mixture of metallic beryllium and unreacted or entrained molten salt (such as fluoride). The electrolytic cathode product is about 5% metallic beryllium wrapped in a large amount of fluoride molten salt. Reasonable processing of the electrolytic cathode product is a key link for obtaining high-purity metallic beryllium, improving process efficiency and ensuring product quality.

[0003] At present, the method for separating metallic beryllium from the electrolytic cathode product is to subject the electrolytic cathode to high-temperature vacuum distillation. The fluoride in the cathode product is volatilized into a gaseous state, and the melting point of metallic beryllium is higher, so it remains in a solid state, thereby separating the metallic beryllium wrapped in the fluoride molten salt. If the recovery rate and the recovery purity of metallic beryllium are to be improved, a longer time of high-temperature vacuum distillation treatment is required, which increases the energy consumption of high-temperature vacuum distillation. Therefore, in the existing recovery process of metallic beryllium from the electrolytic cathode product, it is impossible to balance the recovery effect (recovery rate and recovery purity) and the recovery cost and recovery efficiency. SUMMARY

[0004] (I) Technical problems to be solved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present application provides a method for separating and obtaining high-purity metallic beryllium from an electrolytic cathode product, which solves the technical problem that the purity of beryllium cannot be balanced with the recovery cost and recovery efficiency when separating metallic beryllium from an electrolytic cathode product in the prior art.

[0006] (II) Technical solutions

[0007] In order to achieve the above-mentioned purposes, the main technical solutions adopted by the present application include:

[0008] In a first aspect, the present application provides a method for separating and obtaining high-purity metallic beryllium from an electrolytic cathode product, comprising the following steps:

[0009] S1, crushing and drying the electrolytic cathode product to prepare a first product; wherein the first product is a mixture of metallic beryllium and fluoride molten salt;

[0010] S2, the first product is raised to the first temperature under vacuum conditions to melt the fluoride molten salt therein, then an auxiliary electric field is applied, and the beryllium metal particles sink to the lower layer; then the temperature is continuously raised to the second temperature, and vacuum distillation is carried out at the second temperature to volatilize and recycle the upper layer fluoride molten salt in a gaseous state, to obtain primary beryllium metal; then the temperature is continuously raised to the second temperature, and vacuum distillation is carried out at the second temperature to volatilize and recycle the upper layer fluoride molten salt in a gaseous state, to obtain primary beryllium metal;

[0011] S3, the primary beryllium metal is cleaned by an aluminum sulfate solution, and then dried to obtain pure beryllium metal.

[0012] On the basis of the molten treatment of the electrolytic cathode product (a mixture of beryllium metal and fluoride molten salt, such as FLiBe, LiF-BeF2-NaF system), a new direct current / pulse electric field auxiliary mechanism is added, which takes advantage of the difference between the ionization characteristics of fluoride molten salt at high temperature (650-1000℃) and the neutral solid state properties of beryllium metal, and drives the directional migration of charged molten salt ions through electric field force, to strengthen the separation effect of "molten salt floating and volatilizing-beryllium metal sinking and remaining". In addition, the electric field disturbance provided by this scheme for the molten state electrolytic cathode product can accelerate the release of beryllium metal particles wrapped from the inside of the fluoride molten salt, and improve the recovery rate and purity of beryllium metal.

[0013] As a preferred embodiment of the present application, in the method for separating and obtaining high-purity beryllium metal from the electrolytic cathode product, in S2, when the auxiliary electric field is applied, the first product is placed in a graphite container, the graphite container serves as a cathode, and a graphite hole plate above the graphite container serves as an anode.

[0014] The auxiliary electric field is pulse direct current, the output voltage is 3-16V, the pulse frequency is 10-50Hz, and the duty cycle is 15%-30%.

[0015] The working mode of the auxiliary electric field is to stop for 3-5min every 5-10s of work.

[0016] The auxiliary electric field is pulse direct current, the output voltage is 3-16V, the pulse frequency is 10-50Hz, and the duty cycle is 15%-30%. The above pulse power supply periodically interrupts the current through "on-off", so that the ion concentration can be relaxed and restored, ensuring that the electric field is mainly used for dielectrophoresis / electrophoresis to drive particle migration, rather than causing unnecessary electrolysis. 3-16V provides an electric field of about 100-500V / m, which is sufficient to drive the directional migration of charged molten salt ions and promote efficient stripping between them and Be particles, while maintaining the electrochemical inertness of the system. The working mode of the auxiliary electric field is intermittent, which can reduce the energy consumption of beryllium separation while meeting the requirements of providing sufficient electric field driving effect.

[0017] As a preferred embodiment of the present application, in S2, the first temperature is 650-800℃, and the fluoride melt in the first product is melted under the following conditions: the temperature is raised to 650-800℃ at a rate of 3-5℃ / min under vacuum, and the temperature is kept for 30-40min.

[0018] As a preferred embodiment of the present application, in S2, when the upper layer fluoride melt is removed by vacuum distillation, the evaporated gaseous fluoride melt is collected and condensed into solid fluoride melt.

[0019] As a preferred embodiment of the present application, in S2, the second temperature is 900-1000℃, and when the upper layer fluoride melt is removed by vacuum distillation, an auxiliary electric field is kept, the temperature is raised to 900-1000℃ at a rate of 5-8℃ / min, the distillation is kept for 0.5-3h, and the charged melt ions are accelerated to evaporate under the electric field force and the vacuum negative pressure, so that a solid layer of primary metal beryllium is prepared at the bottom of the graphite container.

[0020] As a preferred embodiment of the present application, after the distillation in S2 is finished, the vacuum is closed, the graphite container is taken out after the distillation kettle is cooled to room temperature, and the primary metal beryllium is collected.

[0021] As a preferred embodiment of the present application, in S1, the electrolytic cathode product is crushed to a particle size of ≤5mm.

[0022] In S3, the aluminum sulfate solution cleaning process is as follows: 0.1-0.5mol / L aluminum sulfate solution with pH of 3-3.5 is mixed with the primary metal beryllium at a solid-liquid mass / volume ratio of 1:5-10, and the mixture is ultrasonically cleaned for 1-3h.

[0023] The solid-liquid separation is performed, and the solid is retained.

[0024] The primary metal beryllium is cleaned with 0.1-0.5mol / L aluminum sulfate solution, which on the one hand ensures sufficient Al 3+ to complex F - , and on the other hand avoids the increase of solution viscosity and the rise of mass transfer resistance caused by too high concentration, thereby affecting the ultrasonic cleaning efficiency. At the same time, the pH of the aluminum sulfate solution is adjusted to 3-3.5, which can inhibit the hydrolysis of Al 3+ and maintain F - in HF / F - balance, HF can slightly corrode the BeO surface film to expose the internal fluoride salt, and promote F -The complexation reaction is carried out in a forward direction, thereby ensuring the complexation effect.

[0025] As a preferred embodiment of the present application, in S3, the solid product is rinsed with deionized water for 4-6 times until the pH of the last rinsing liquid is 7-8; and the solid product after water rinsing is vacuum dried at 120-130 DEG C for 2-4 hours to obtain pure metal beryllium.

[0026] (Three) beneficial effects

[0027] The beneficial effects of the present application are: the method for separating and obtaining high-purity metal beryllium from electrolytic cathode product belongs to the small test stage of metal beryllium separation, and the scheme is to first melt the fluoride salt in the first product after crushing and drying under vacuum conditions, and under the driving of an auxiliary electric field, on the one hand, the difference between the ionization characteristics of the fluoride salt at high temperature and the neutral solid state of the metal beryllium is utilized, the charged molten salt ions are driven to migrate directionally by the electric field force, the metal beryllium particles in the solid phase of the first product sink to the lower layer, and the molten fluoride salt floats to the upper layer; the upper layer fluoride salt is removed by vacuum distillation to obtain primary metal beryllium, the separation effect of "molten salt floating and volatilizing-metal beryllium sinking and remaining" is strengthened, the vacuum distillation time is reduced, and the recovery efficiency and purity of the metal beryllium particles are improved; on the other hand, the auxiliary electric field drives the movement of the charged ions of the fluoride, which can promote the stripping of the metal beryllium particles from the fluoride salt, and further improve the recovery rate of the metal beryllium particles; then the primary metal beryllium product is cleaned with aluminum sulfate solution, in this process, the fluoride (lithium fluoride, beryllium fluoride) reacts with aluminum sulfate to dissolve, the main reaction is F - and Al 3+ combine to form soluble [AlF6] 3- complex ions, remove the fluoride salt in the primary metal beryllium, and further improve the recovery purity of the metal beryllium. Compared with the prior art, the method can improve the separation purity and efficiency of the metal beryllium separated from the electrolytic cathode product, the purity of the separated metal beryllium is as high as 99.94%-99.97%, the recovery cost and economic benefit of the metal beryllium are considered, and the method can be scaled up and applied. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The picture of the high-purity metal beryllium prepared in Example 1 of the present application is enlarged by 160 times by a microscope;

[0029] Figure 2 The picture of the high-purity metal beryllium prepared in Example 1 of the present application is enlarged by 160 times by a microscope;

[0030] Figure 3 The schematic diagram of the reaction device used in the embodiment of the present application is shown. DETAILED DESCRIPTION

[0031] For a better understanding of the above technical solutions, the exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present application can be more clearly, thoroughly understood and the scope of the present application can be completely conveyed to those skilled in the art.

[0032] Embodiment 1

[0033] The present embodiment provides a method for obtaining high-purity metal beryllium from electrolytic cathode product, specifically comprising the following steps:

[0034] (1) Pretreatment of electrolytic cathode product: dry the electrolytic cathode product (metal beryllium mixed with fluoride salt, such as FLiBe, LiF-BeF2-NaF system, beryllium content 50%-70%) in a vacuum drying oven at 120°C for 2h to remove moisture; then crush to a particle size of ≤5mm.

[0035] (2) Loading: uniformly load the pretreated electrolytic cathode product into a high-temperature-resistant graphite boat, and place the boat into a vacuum distillation kettle, with the boat as the cathode of the external electric field.

[0036] As shown in Figure 3 , in the distillation kettle, a porous graphite plate (pore size 2mm, allowing molten salt vapor to pass through) is provided on the graphite boat, and the porous graphite plate serves as the anode, with an electrode spacing of 40mm (which can be adjusted according to the height of the boat); the electrodes are connected to an adjustable DC power supply (output voltage 0-50V, current 0-10A) supporting pulse electric field mode. The power supply is set outside the distillation kettle, and the specific structure of the power supply supplying power to the electrodes inside the distillation kettle is described in the prior art.

[0037] (3) Melting of fluoride salt: under vacuum conditions, start the heating system to rise to 650°C (first temperature) at a rate of 3°C / min, and keep the temperature for 40min to completely melt the fluoride salt; at this time, start the electric field system and apply an auxiliary pulse electric field (DC, voltage 5V, frequency 10Hz, duty cycle 15%), and the working mode of the auxiliary electric field is to work for 5min and stop for 3min.

[0038] The molten fluoride salt is ionized into charged ions, and under the action of electric field force, cations (such as Li + , Na + ) migrate to the cathode, and anions migrate to the anode, forming an interface layer of "molten salt floating and metal beryllium particles sinking".

[0039] (4) Vacuum distillation: under vacuum, continue to increase the temperature to 900°C (second temperature) at a rate of 5°C / min, while maintaining the electric field; keep distilling for 2.5 h, during which the external electric field promotes the interfacial electrochemical reaction, and the vacuum environment reduces the gas phase partial pressure, accelerating the evaporation of the molten fluoride salt components. The melting point of metallic beryllium is between 1278°C and 1283°C, which remains in a solid state in this environment and stays at the bottom of the boat under the action of gravity, obtaining high-purity metallic beryllium.

[0040] (5) Molten salt condensation collection: the gaseous products of the volatilized molten salt enter the condensation collection system with the airflow in the distillation kettle, the temperature of the inner wall of the condensation collector is controlled at 400°C, and the gaseous molten salt condenses into solid molten salt on the condensation wall, and the solid molten salt in the condensation collector is collected regularly;

[0041] (6) Metallic beryllium collection: turn off the vacuum unit, wait for the distillation kettle to cool to room temperature, break the vacuum, open the kettle cover, take out the boat, and collect the primary metallic beryllium with only a small amount of molten salt remaining on the surface.

[0042] (7) Put the primary metallic beryllium into an ultrasonic cleaning tank and perform aluminum sulfate complexation cleaning:

[0043] Liquid preparation: prepare a 0.1 mol / L aluminum sulfate solution with deionized water, and add dilute sulfuric acid to adjust the pH to 3.5;

[0044] Selective cleaning: add the primary metallic beryllium to the aluminum sulfate solution according to the liquid-solid ratio of 10:1 (mL / g), use an ultrasonic cleaning instrument, and continuously clean for 3 h, during which stir every 30 minutes;

[0045] Solid-liquid separation: collect the solid by suction filtration; transfer the solid into a rinsing tank, rinse with deionized water for 5 times, each time for 10 min, until the pH of the last washing liquid is 7-8, and then put it into a 130°C vacuum drying box for drying for 2 h to avoid the reaction of water with beryllium or fluoride salt during distillation. After cleaning with the aluminum sulfate solution, the metallic beryllium can be further purified to obtain high-purity metallic beryllium, see Figure 1 and Figure 2 .

[0046] According to the standard (YS / T 221), the impurity elements in the metallic beryllium recovery product are detected by inductively coupled plasma mass spectrometry (ICP-MS), and the content of metallic beryllium is calculated by difference method to be as high as 99.97%, see Table 1.

[0047] Example 2

[0048] The embodiment provides a method for separating and obtaining high-purity metallic beryllium from an electrolytic cathode product, which specifically comprises the following steps:

[0049] (1) Pretreatment of electrolytic cathode product: The electrolytic cathode product (metal beryllium and fluoride salt mixture, such as FLiBe, LiF-BeF2-NaF system, beryllium content 50%-70%) is dried in a vacuum drying oven at 120°C for 2h to remove moisture; then it is crushed to a particle size of ≤5mm.

[0050] (2) Loading: The pretreated electrolytic cathode product is uniformly loaded into a high-temperature-resistant graphite boat, and the graphite boat is placed in a vacuum distillation kettle, with the graphite boat as the cathode of the external electric field.

[0051] Referring to Figure 3 In the distillation kettle, a porous graphite plate (pore size 2mm, allowing molten salt vapor to pass through) is provided on the graphite boat, and the porous graphite plate serves as the anode, with an electrode spacing of 40mm (which can be adjusted according to the height of the boat); the electrodes are connected to a variable direct current power supply (output voltage 0-50V, current 0-10A) that supports pulse electric field mode.

[0052] (3) Melting of fluoride salt: Under vacuum conditions, the heating system is started, and the temperature is raised to 800°C at a rate of 5°C / min, and maintained for 30min to completely melt the fluoride salt; at this time, the electric field system is started, and an auxiliary pulse electric field (direct current, voltage 16V, frequency 50Hz, duty cycle 30%) is applied, with the auxiliary electric field working for 10s and stopping for 5min.

[0053] (4) Vacuum distillation: Under vacuum conditions, the temperature is continued to be raised to 1000°C at a rate of 8°C / min, while the electric field is maintained; the temperature is maintained for 1h of distillation, during which the external electric field promotes the interfacial electrochemical reaction, and the vacuum environment reduces the gas phase partial pressure, accelerating the evaporation of the molten fluoride salt components. The metal beryllium, being neutral and in solid phase, remains at the bottom of the boat under the action of gravity, and high-purity metal beryllium is obtained.

[0054] (5) Condensation and collection of molten salt: The gaseous molten salt product volatilized from the distillation kettle enters the condensation and collection system with the airflow in the kettle, and the inner wall temperature of the condensation and collection system is controlled at 300°C. The gaseous molten salt condenses into solid molten salt on the condensation wall, and the solid molten salt in the condensation and collection system is collected regularly.

[0055] (6) Collection of metal beryllium: The vacuum unit is turned off, the distillation kettle is cooled to room temperature, the vacuum is broken, the kettle cover is opened, and the boat is removed, and the primary metal beryllium with only a small amount of residual molten salt on the surface is collected.

[0056] (7) The primary metal beryllium is placed in an ultrasonic cleaning tank for aluminum sulfate complexing cleaning:

[0057] Liquid preparation: 0.5mol / L aluminum sulfate solution is prepared with deionized water, and dilute sulfuric acid is added to adjust the pH to 3;

[0058] Selective cleaning: the broken electrolytic cathode product was added into aluminum sulfate solution according to the liquid-solid ratio of 5:1 (mL / g), and an ultrasonic cleaning instrument was used for continuous cleaning for 1 h, and stirring was performed once every 30 min during the cleaning;

[0059] Solid-liquid separation: the solid was collected by suction filtration; the solid was transferred into a rinsing tank, and was rinsed with deionized water for 4 times, each time for 15 min, until the pH of the last washing liquid was 7-8, and then was placed into a 120 DEG C vacuum drying box for drying for 4 h, so as to avoid the reaction between water and beryllium or fluoride salt during distillation, and high-purity metal beryllium was obtained.

[0060] According to the standard (YS / T 221), the impurity elements in the metal beryllium recovery product were detected by inductively coupled plasma mass spectrometry (ICP-MS), and the content of the metal beryllium was calculated by difference method to be as high as 99.96%, and specific reference was made to Table 1.

[0061] Example 3

[0062] The embodiment provides a method for separating and obtaining high-purity metal beryllium from an electrolytic cathode product, and the difference between the embodiment and example 1 lies in that:

[0063] In (3), fluoride salt melting: under vacuum conditions, the heating system was started, and was raised to 730 DEG C at a temperature raising rate of 7 DEG C / min, and was kept for 35 min, so that the fluoride salt was completely melted; at this time, the electric field system was started, and an auxiliary pulse electric field (direct current, voltage 10 V, frequency 30 Hz, and duty cycle 20%) was applied.

[0064] The remaining steps are the same;

[0065] According to the standard (YS / T 221), the impurity elements in the metal beryllium recovery product were detected by inductively coupled plasma mass spectrometry (ICP-MS), and the content of the metal beryllium was calculated by difference method to be as high as 99.94%, and specific reference was made to Table 1.

[0066] Example 4

[0067] The embodiment provides a method for separating and obtaining high-purity metal beryllium from an electrolytic cathode product, and the difference between the embodiment and example 1 lies in that:

[0068] In (4), vacuum distillation: under vacuum conditions, the temperature was continuously raised to 950 DEG C at a temperature raising rate of 6 DEG C / min, and the electric field was kept; distillation was kept for 1.5 h, and the interface electrochemical reaction was promoted by the external electric field during the distillation, and the evaporation of the molten fluoride salt components was accelerated by combining the vacuum environment with the reduction of the gas phase partial pressure.

[0069] The remaining steps are the same;

[0070] According to the standard (YS / T 221), the impurity elements in the recovered beryllium metal products were detected by inductively coupled plasma mass spectrometry (ICP-MS). The beryllium metal content was calculated to be as high as 99.95% by the difference method, as shown in Table 1.

[0071] Comparative Example 1

[0072] This comparative example provides a method for separating and obtaining high-purity metallic beryllium from electrolytic cathode products. The difference between this comparative example and Example 1 is as follows:

[0073] In (3), the effect of the auxiliary electric field is cancelled;

[0074] The remaining steps are the same;

[0075] The beryllium content in the separated products was found to be as high as 98.07% using inductively coupled plasma mass spectrometry (ICP-MS).

[0076] Table 1. Mass percentage of major components in the separated products of different embodiments and comparative examples

[0077]

[0078] Referring to Table 1, the analysis based on the above embodiments and comparative examples is as follows:

[0079] The methods for separating and obtaining high-purity metallic beryllium from electrolytic cathode products provided in Examples 1 to 4 have a beryllium content as high as 99.94%-99.97% in the separated high-purity metallic beryllium.

[0080] Comparing Example 1 with Comparative Example 1, it can be seen that if the other steps remain unchanged, the removal of the auxiliary electric field will significantly affect the purity of metallic beryllium.

[0081] It should be noted that the embodiments of the present invention employ... Figure 3 The reaction apparatus is designed for the pilot-scale separation and purification of metallic beryllium. If the separation and purification process of metallic beryllium is to be expanded, the vacuum distillation vessel and the boat that can apply an auxiliary electric field can be coupled into a whole device. The corresponding purification process parameters (fluoride molten salt melting, vacuum distillation, etc.) can be adjusted as needed.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for separating and obtaining high-purity metallic beryllium from electrolytic cathode products, characterized in that, Includes the following steps: S1. The first product is prepared by pulverizing and drying the electrolytic cathode product; wherein the first product is a mixture of metallic beryllium and fluoride molten salt; S2. The first product is heated to a first temperature under vacuum to melt the fluoride molten salt therein. An auxiliary electric field is then applied, which causes the molten fluoride molten salt ions in the first product to float and be rapidly disturbed. The beryllium metal particles sink to the lower layer. The temperature is then further increased to a second temperature, and vacuum distillation is performed at the second temperature to cause the upper fluoride molten salt to evaporate in a gaseous state and be recovered, thus obtaining primary beryllium metal. S3. The primary metallic beryllium is washed with aluminum sulfate solution and then dried to obtain pure metallic beryllium.

2. The method for separating and obtaining high-purity metallic beryllium from electrolytic cathode products as described in claim 1, characterized in that, In S2, when an auxiliary electric field is applied, the first product is placed in a graphite container, which serves as the cathode, and the graphite perforated plate located above the graphite container serves as the anode. The auxiliary electric field is a pulsed DC current with an output voltage of 3-16V, a pulse frequency of 10-50Hz, and a duty cycle of 15%-30%. The auxiliary electric field operates by pausing for 3-5 minutes every 5-10 seconds.

3. The method for separating and obtaining high-purity metallic beryllium from electrolytic cathode products as described in claim 2, characterized in that, In S2, the first temperature is 650-800℃. The conditions for melting the fluoride molten salt in the first product are: heating to 650-800℃ at a heating rate of 3-5℃ / min under vacuum, and holding at that temperature for 30-40min.

4. The method for separating and obtaining high-purity metallic beryllium from electrolytic cathode products as described in claim 3, characterized in that, In S2, when the upper layer of fluoride molten salt is removed by vacuum distillation, the volatilized gaseous fluoride molten salt is collected and condensed into solid fluoride molten salt.

5. The method for separating and obtaining high-purity metallic beryllium from the electrolytic cathode product as described in claim 2, 3, or 4, characterized in that, In S2, the second temperature is 900-1000℃. When the upper fluoride molten salt is removed by vacuum distillation, the auxiliary electric field is maintained and the temperature is raised to 900-1000℃ at a rate of 5-8℃ / min. Distillation is carried out for 0.5-3 hours. The charged molten salt ions are accelerated to volatilize under the action of electric field force and vacuum negative pressure, and a solid layer of primary metallic beryllium is obtained at the bottom of the graphite container.

6. The method for separating and obtaining high-purity metallic beryllium from electrolytic cathode products as described in claim 5, characterized in that, After distillation in S2 is complete, the vacuum is turned off. After the distillation vessel has cooled to room temperature, the vacuum is broken, the graphite container is removed, and the primary metallic beryllium is collected.

7. The method for separating and obtaining high-purity metallic beryllium from electrolytic cathode products as described in claim 1, characterized in that, In S1, the particle size of the electrolytic cathode product after crushing is ≤5mm; In S3, the aluminum sulfate solution cleaning process is as follows: mix 0.1-0.5 mol / L aluminum sulfate solution with pH 3-3.5 with primary metal beryllium at a solid-liquid mass-to-volume ratio of 1:5-10, and ultrasonically clean for 1-3 hours. Solid-liquid separation, retaining the solid matter.

8. The method for separating and obtaining high-purity metallic beryllium from electrolytic cathode products as described in claim 7, characterized in that, In S3, the solid is rinsed with deionized water 4-6 times until the pH of the final wash solution is 7-8; the washed solid is then vacuum dried at 120-130℃ for 2-4 hours to obtain pure metallic beryllium.

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