CN113981491B - Method for preparing metallic beryllium by low-temperature molten salt electrolysis - Google Patents

Abstract

The invention discloses a method for preparing metal beryllium by electrolysis of low-temperature molten salt. A low-temperature liquid alloy is used to connect an anode working area and a cathode working area in an isolated state, raw materials containing beryllium enter the anode working area, and are electrolyzed by an electric field at a low temperature to produce beryllium-containing materials. The raw material is reduced to metal beryllium and dissolved into the low-temperature liquid alloy. At the same time, the beryllium in the low-temperature liquid alloy is oxidized into beryllium ions in the cathode working area, and then the solid metal beryllium is deposited by electron reduction at the cathode. The present invention adds an oxygen-containing auxiliary agent into the electrolyte to increase the solubility of the beryllium-containing raw material, expand the application range of the beryllium-containing raw material, and reduce the requirement for low purity of the raw material. The invention adds silicon to the liquid alloy, which increases the fluidity of the liquid alloy, reduces its thermal expansion, greatly reduces the melting point of the alloy, lowers the electrolysis temperature, reduces electrolysis energy consumption, and reduces volatilization loss of beryllium. The process of the invention is simple, and the obtained metal beryllium has high purity, which is a great innovation in the field of beryllium metallurgy.

Description

A method for preparing metal beryllium by low-temperature molten salt electrolysis

technical field

The invention relates to a method for preparing metal beryllium by low-temperature molten salt electrolysis, which belongs to the field of beryllium metallurgy.

Background technique

Beryllium is a silver-white metal that is 17 times more transparent to X-rays than aluminum, and is the only material used to make X-ray tube windows and radiation detection probes. Metal beryllium has a small neutron capture surface and a large neutron scattering cross section, and is often used in the manufacture of neutron breeding devices, reactor reflectors, moderators and nuclear weapon components. In addition, beryllium can be made into beryllium gyroscope, which is widely used in aerospace field. Therefore, beryllium is a metal of great strategic importance.

At present, most enterprises use beryllium fluoride magnesium thermal reduction method to produce metal beryllium, but there are also a small number of enterprises that use beryllium chloride electrolysis method to produce metal beryllium. Beryllium fluoride magnesium thermal reduction method first dissolves beryllium oxide or beryllium hydroxide in ammonium bifluoride to produce ammonium fluoroberyllium, then heats ammonium fluoroberyllium to decompose it to obtain ammonium fluoride and beryllium fluoride, and finally, use metal magnesium The method of reducing beryllium fluoride to obtain metal beryllium is widely used in industry, but the method is a batch operation and cannot be produced continuously. At the same time, the preparation process of beryllium fluoride is cumbersome and the production cost is relatively high. The beryllium chloride electrolysis method first chlorinates beryllium oxide to obtain beryllium chloride, and then electrolyzes beryllium chloride to obtain metal beryllium. Different from the magnesium thermal reduction method of beryllium fluoride, this method can continuously produce metal beryllium, but the preparation of beryllium chloride is very difficult, because beryllium oxide is difficult to be chlorinated, and carbon needs to be introduced. At the same time, chlorine gas will be generated during the electrolysis of beryllium chloride ,polluted environment.

U.S. Patent US 1980378A discloses a method for producing metal beryllium and its light alloys by electrolysis of molten salts. The method uses fluoride as a molten salt, dissolves beryllium fluoride or beryllium oxide in molten fluoride salts, and prepares beryllium or beryllium by electrolysis. Light alloys of beryllium. When using beryllium oxide as raw material for electrolysis, in order to ensure the dissolution of beryllium oxide, the addition rate of beryllium oxide must be strictly controlled. When using beryllium fluoride as raw material for electrolysis, fluorine gas will be precipitated at the anode, which is very harmful to the environment.

Chinese patent CN 109295309 B discloses a method for preparing metal beryllium by reducing beryllium chloride. The method utilizes sodium or potassium to reduce beryllium chloride to prepare metal beryllium. The preparation of high-purity metal beryllium can be realized through two steps of reduction and fractional distillation. , but this method cannot be produced continuously. At the same time, this method needs to use beryllium chloride as a raw material, but as mentioned above, the chlorination of beryllium oxide is very difficult.

Besides beryllium chloride and beryllium fluoride, beryllium oxide can also be used to prepare metal beryllium. U.S. Patent No. 6,811,678 B2 discloses a method for preparing metal beryllium by electrochemical reduction of beryllium oxide. In this method, metallic calcium is first obtained at the cathode of beryllium oxide through electrolytic reduction, and then the metallic calcium reacts with beryllium oxide to reduce beryllium oxide. For metal beryllium, this method can be continuously produced, but metal calcium will dissolve in molten salt, which will increase the electronic conductivity of molten salt and cause a decrease in current efficiency. At the same time, the metal beryllium obtained by reduction will easily contain CaBe ₁₃ impurities. Chinese patent CN 111235603 A discloses a method for preparing metal beryllium by electrodeoxidation of molten salt. In this method, beryllium oxide is uniformly mixed with a pore-forming agent and a conductive agent to make a cathode sheet. The obtained metal beryllium will be wrapped on the surface of the electrode, hindering the diffusion of oxygen ions inside the electrode, making it difficult for the oxygen inside the electrode to diffuse out. At the same time, this method requires the purity of beryllium oxide to be above 99%, which is poor in adaptability to raw materials.

Contents of the invention

Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a method for efficiently preparing metal beryllium at low temperature, the method has a simple process, and the obtained metal beryllium has high purity.

In order to achieve the above object, technical scheme of the present invention is:

A method for preparing metal beryllium by low-temperature molten salt electrolysis, using a low-temperature liquid alloy to connect an isolated anode working area and a cathode working area, the beryllium-containing raw material enters the anode working area, and is electrolyzed by an electric field at a low temperature, and the beryllium-containing raw material is reduced to The metal beryllium is dissolved into the low-temperature liquid alloy, and at the same time, the beryllium in the low-temperature liquid alloy is oxidized into beryllium ions in the cathode working area, and then the solid metal beryllium is deposited by electron reduction at the cathode.

Specifically, the following steps are included:

(1) The electrolytic cell is divided into an anode work area and a cathode work area, the anode work area and the cathode work area are filled with electrolyte, and the bottom of the electrolytic cell is also filled with a low-temperature liquid alloy; the electrolyte in the anode work area and the cathode work area They are not in contact with each other but connected by the low-temperature liquid alloy at the bottom of the electrolytic cell;

(2) Add beryllium-containing raw materials into the anode working area, then insert the anode and cathode respectively in the anode working area and the cathode working area, and electrify at low temperature, and the beryllium-containing raw materials are reduced to metal at the interface between the electrolyte and the low-temperature liquid alloy in the anode working area The beryllium is dissolved into the cryogenic liquid alloy, and at the same time, the beryllium in the cryogenic liquid alloy is oxidized into beryllium ions at the interface between the cryogenic liquid alloy and the cathode working area electrolyte, enters the cathode electrolyte, and is reduced to metal beryllium on the surface of the cathode.

Further, the low temperature is <600°C.

Further, the low-temperature liquid alloy contains 53-85 at.% gold, 0-38 at.% beryllium, 0-20 at.% silicon, and may contain one or more of copper, silver, and manganese, which is liquid at <600°C .

Further, the beryllium-containing raw material is at least one of beryllium oxide, beryllium fluoride, and beryllium chloride, and the purity of the beryllium-containing raw material is ≥50%.

Preferably, the low-temperature liquid alloy contains 54-81 at.% gold, 0.1-38 at.% beryllium, and 6-18 at.% silicon.

Further, the electrolysis process is controlled by one or more of current control and voltage control; when controlling current, the current density is 0.01-1.0A/cm ² , and when controlling voltage, the cathode voltage is ≤-2.5V (vs NHE).

Further, the electrolyte in the anode working area and the cathode working area is composed of molten salt electrolyte and auxiliary agent, and the amount of auxiliary agent added is ≤10 at.%.

Further, the molten salt electrolyte is lithium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, beryllium fluoride, lithium chloride, sodium chloride, potassium chloride, rubidium chloride, cesium chloride, Beryllium, magnesium chloride, calcium chloride, strontium chloride, barium chloride, lanthanum chloride, praseodymium chloride, scandium chloride, neodymium chloride, samarium chloride, thorium chloride, lithium bromide, sodium bromide, potassium bromide, At least one of rubidium bromide, cesium bromide, lithium iodide, sodium iodide, potassium iodide, rubidium iodide, cesium iodide; the auxiliary agent is lithium oxide, sodium oxide, potassium oxide, beryllium oxide, magnesium oxide, At least one of calcium oxide and barium oxide.

Further, the anode is one of an inert anode and an active anode; the cathode is at least one of platinum, gold, iron, silver, aluminum, copper, barium, cobalt, chromium, mercury, molybdenum, nickel, and graphite.

Further, the inert anode material is at least one of alloys and cermets; the active anode material is at least one of graphite, semi-graphite, graphite, graphene, carbon nanotubes, and carbon fibers.

Beneficial effects of the present invention:

1. The raw material purity requirement is low, and the product purity is higher. The method for preparing high-purity metal beryllium by low-temperature electrolysis of the present invention separates two electrolytic working areas by a low-temperature liquid alloy, and adds beryllium-containing raw materials into the anode working area, and the metal beryllium obtained by reducing the beryllium-containing raw materials can be directly dissolved into the Liquid alloy, wherein more negative ions than beryllium potential will not enter the liquid alloy from the anode working area, although more positive ions than the beryllium potential will enter the liquid alloy, but will not enter the cathode working area from the liquid alloy, therefore, the present invention can be very It is good for removing impurities in raw materials, reducing the purity requirements for raw materials containing beryllium, and has good adaptability of raw materials.

2. The sources of raw materials are more abundant. The method for preparing high-purity metal beryllium by low-temperature electrolysis of the present invention is different from molten salt electrolysis that requires beryllium oxide as a raw material, and magnesium reduction method that uses beryllium fluoride as a raw material or molten salt electrolysis that uses beryllium chloride as a raw material. The oxygen-containing auxiliary agent in the electrolyte is invented to increase the solubility of the beryllium-containing raw material, so the beryllium-containing raw material of the present invention can be one or more of beryllium oxide, beryllium fluoride, and beryllium chloride. At the same time, the increase in the solubility of beryllium-containing raw materials can greatly reduce the dependence of beryllium ions or complex ions on beryllium-containing raw materials, and further reduce the requirements for their purity. According to the application process requirements, the sources of beryllium-containing raw materials are more abundant.

3. Low operating temperature and low energy consumption. The electrolysis temperature of the present invention is lower (<600 DEG C), can reduce electrolysis energy consumption, and reduce volatilization loss of beryllium. The invention adds silicon into the liquid alloy, which increases the fluidity of the liquid alloy, reduces its thermal expansion, and greatly reduces the melting point of the alloy.

4. The concentration of beryllium ions in the electrolytic system is relatively high. By adding oxygen-containing auxiliary agents into the electrolyte, oxygen, halogen and beryllium form beryllium oxyhalide complex ions, which increases the solubility of beryllium-containing raw materials and the concentration of beryllium-containing ions in the electrolytic system.

5. The conductivity of the electrolyte system is high. Increasing the alkali metal and alkaline earth metal halide ionic compounds can increase the ion concentration in the electrolyte, reduce the viscosity of the system, and then improve the conductivity of the system.

6. Feed speed limit less. In the method for preparing high-purity metal beryllium by low-temperature electrolysis of the present invention, the beryllium-containing raw material can be dissolved in the electrolyte to cause ion diffusion, or it can be insoluble in the electrolyte, and the electrochemical reaction only occurs at the liquid-solid interface (electrolyte and solid raw material interface), reducing Requirements for feed rate.

7. In the method for preparing high-purity beryllium metal by low-temperature electrolysis of the present invention, the anode working area and the cathode working area in the preferred electrolytic cell structure are center-symmetrical, the electromagnetic field is more evenly distributed, and the tank has better thermal insulation.

Description of drawings

Figure 1 is a schematic diagram of a typical electrolysis device of the present invention. Among them, Fig. 1(1)-(4) shows different setting modes, the anode area and the cathode area correspond to the anode working area and the cathode working area. Among them, 1 is the cathode, 2 is the anode, 3 is the alloy area, 4 is the cathode area, and 5 is the anode area.

Detailed ways

The specific implementation of the present invention will be described in further detail below in conjunction with the examples.

Example 1

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add a beryllium-containing alloy (37.7at.% beryllium, 8.2at.% silicon, 54.1at.% gold) to the bottom of the electrolytic cell to ensure that the electrolytic device can be divided into an anode working area after melting , cathode working area, add 59at.% lithium chloride, 39at.% potassium chloride, 1at.% lithium oxide, 1at.% beryllium oxide mixture into the anode working area as the anode electrolyte, add 58.5at The mixture of .% lithium chloride, 41at.% potassium chloride and 0.5at.% beryllium oxide is used as catholyte; when heated, it becomes molten or suspended.

(2) Add beryllium oxide with a purity of 50% to the anode working area, raise the temperature of the electrolytic cell to 599°C, and keep the temperature constant for more than 0.5h. Insert the graphite anode and iron cathode into the anode electrolyte and cathode electrolyte respectively, and conduct constant temperature electrolysis with electricity to control the current The density is 1.0A/cm ² , the electrolysis is for 12 hours, and the solid metal beryllium is obtained at the cathode, and the purity of the solid metal beryllium obtained by analysis is 99.0%.

Example 2

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add a beryllium-containing alloy (3.1at.% beryllium, 16.8at.% silicon, 80.1at.% gold) to the bottom of the electrolytic cell to ensure that the electrolytic device can be divided into an anode working area after melting , cathode working area, add a mixture of 61at.% calcium chloride, 36at.% lithium chloride, 2.5at.% calcium oxide, 0.5at.% beryllium oxide to the anode working area as the anode electrolyte, and add A mixture of 55.5at.% lithium chloride, 43.4at.% rubidium chloride, 0.1at.% potassium oxide, and 1at.% beryllium oxide is used as the catholyte; it is molten or suspended when heated.

(2) Add beryllium oxide with a purity of 60% to the anode working area, raise the temperature of the electrolytic cell to 370°C, and keep the temperature at a constant temperature for more than 0.5h. Insert the graphite anode and platinum cathode into the anode electrolyte and cathode electrolyte respectively, and conduct electrolysis at a constant temperature with power on. The current density is 0.8A/cm ² , electrolysis is performed for 3 hours, and solid metal beryllium is obtained at the cathode. The purity of the solid metal beryllium obtained by analysis is 99.2%.

Example 3

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add beryllium-containing alloy (7.9at.% beryllium, 12.3at.% silicon, 78.3at.% gold, 0.7at.% copper, 0.8at.% silver) to the bottom of the electrolytic cell to ensure After melting, the electrolysis device can be divided into an anode working area and a cathode working area, and a mixture of 66 at.% potassium bromide, 33 at.% lithium bromide, 0.5 at.% calcium oxide and 0.5 at.% beryllium oxide is added to the anode working area As an anode electrolyte, a mixture of 62.5 at.% lithium iodide, 36.5 at.% potassium iodide and 1 at.% beryllium oxide is added to the cathode working area as the catholyte; it becomes molten or suspended when heated.

(2) Add beryllium oxide with a purity of 80% to the anode working area, raise the temperature of the electrolytic cell to 450°C, and keep the temperature at a constant temperature for more than 0.5h. Insert the carbon fiber anode and molybdenum cathode into the anode electrolyte and cathode electrolyte respectively, and electrolyze at a constant temperature with power on. The current density is 0.01A/cm ² , electrolysis is performed for 15 hours, and solid metal beryllium is obtained at the cathode. The purity of the solid metal beryllium obtained by analysis is 99.5%.

Example 4

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add beryllium-containing alloy (0.2at.% beryllium, 18.0at.% silicon, 81.0at.% gold, 0.5at.% copper, 0.3at.% manganese) to the bottom of the electrolytic cell to ensure After it is melted, the electrolysis device can be divided into an anode working area and a cathode working area, and a mixture of 17.5 at.% scandium chloride, 82 at.% lithium iodide, and 0.5 at.% beryllium oxide is added to the anode working area as the anode electrolyte. Add a mixture of 45at.% beryllium chloride, 54at.% sodium chloride, and 1at.% lithium oxide into the cathode working area as the catholyte; it will be molten or suspended when heated.

(2) Add beryllium fluoride with a purity of 50% into the anode working area, raise the temperature of the electrolytic cell to 400° C., and keep the temperature constant for more than 0.5 hours. Insert the cermet anode and nickel cathode into the anode electrolyte and the cathode electrolyte respectively, and electrolyze at a constant temperature with electricity. The current density is controlled at 0.5A/cm ² , electrolysis is performed for 3 hours, and solid metal beryllium is obtained at the cathode. The purity of the solid metal beryllium obtained by analysis is 99.7%.

Example 5

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add beryllium-containing alloy (24.7at.% beryllium, 6.3at.% silicon, 68.4at.% gold, 0.1at.% manganese, 0.2at.% copper, 0.3at .% silver), to ensure that the electrolytic device can be divided into an anode work area and a cathode work area after melting, add 60at.% sodium chloride, 36at.% scandium chloride, 3at.% calcium oxide, 1at A mixture of .% beryllium oxide is used as the anode electrolyte, and a mixture of 10 at.% lithium fluoride and 90 at.% beryllium fluoride is added to the cathode working area as the cathode electrolyte; it becomes molten or suspended when heated.

(2) Add beryllium fluoride with a purity of 70% to the anode working area, raise the temperature of the electrolytic cell to 580°C, and keep the temperature constant for more than 0.5h. Insert the graphite anode and the silver cathode into the anode electrolyte and the cathode electrolyte respectively, and electrolyze at a constant temperature with power on. The current density is 0.8A/cm ² , and the electrolysis takes 4 hours to obtain solid metal beryllium at the cathode. The purity of the solid metal beryllium obtained by analysis is 99.9%.

Example 6

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add beryllium-containing alloy (14.3at.% beryllium, 11.2at.% silicon, 74.0at.% gold, 0.5at.% silver) to the bottom of the electrolytic cell to ensure that it can be electrolyzed after melting The device is divided into an anode working area and a cathode working area. A mixture of 40 at.% lithium chloride, 55.5 at.% rubidium chloride, 4 at.% barium oxide and 0.5 at.% beryllium oxide is added to the anode working area as the anode electrolyte. Add a mixture of 23at.% lithium fluoride, 73at.% lithium iodide, 3.5at.% lithium oxide, and 0.5at.% beryllium oxide into the cathode working area as the catholyte; it will be molten or suspended when heated.

(2) Adding beryllium chloride with a purity of 80% to the anode working area, the electrolytic cell is heated to 595° C., and kept at a constant temperature for more than 0.5 hours. The graphene anode and the graphite cathode are respectively inserted into the anode electrolyte and the cathode electrolyte, and electrolyzed at a constant temperature with electricity. The current density is controlled at 0.3A/cm ² , electrolysis is performed for 6 hours, and solid metal beryllium is obtained at the cathode. The purity of the solid metal beryllium obtained by analysis is 99.5%.

Example 7

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add a beryllium-containing alloy (11.3at.% beryllium, 9.1at.% silicon, 79.6at.% gold) to the bottom of the electrolytic cell to ensure that the electrolytic device can be divided into an anode working area after melting , Cathode working area, add the mixture of 48at.% sodium chloride, 48at.% samarium chloride, 3at.% sodium oxide, 1at.% beryllium oxide to the anode working area as the anode electrolyte, add 41at.% to the cathode working area A mixture of % potassium chloride, 56 at.% lithium chloride, 2.5 at.% lithium oxide, and 0.5 at.% beryllium oxide is used as the catholyte; it is molten or suspended when heated.

(2) Adding beryllium oxide and 99% beryllium chloride (80at% beryllium chloride) with a purity of 99% to the anode working area, the electrolytic cell is heated up to 440°C, and the temperature is maintained for more than 0.5h, and the semi-graphite anode and The nickel cathode was inserted into the anode electrolyte and the cathode electrolyte respectively, energized and electrolyzed at a constant temperature, and the current density was controlled to be 0.5A/cm ² , electrolyzed for 6 hours, and solid metal beryllium was obtained at the cathode, and the purity of the solid metal beryllium obtained by analysis was 99.9%.

Example 8

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add beryllium-containing alloy (3.3at.% beryllium, 17.2at.% silicon, 79.0at.% gold, 0.3at.% copper, 0.2at.% manganese) to the bottom of the electrolytic cell to ensure After it is melted, the electrolysis device can be divided into an anode working area and a cathode working area, and a mixture of 47at.% beryllium chloride and 53at.% sodium chloride is added to the anode working area as the anode electrolyte, and 41at.% is added to the cathode working area. % beryllium chloride, 55 at. % sodium chloride, 4 at. % lithium oxide mixture as the catholyte; heated in molten state or suspended state.

(2) Add beryllium fluoride with a purity of 85% to the anode working area, raise the temperature of the electrolytic cell to 380°C, and keep the temperature at a constant temperature for more than 0.5h, insert the alloy anode and graphite cathode into the anode electrolyte and cathode electrolyte respectively, and electrolyze at a constant temperature with electricity, The current density is controlled at 0.7A/cm ² , electrolysis is performed for 2 hours, and solid metal beryllium is obtained at the cathode. The purity of the solid metal beryllium obtained by analysis is 99.3%.

Example 9

A method for preparing metal beryllium by low-temperature molten salt electrolysis, comprising the following steps:

(1) As shown in Figure 1, add beryllium-containing alloy (3.3at.% beryllium, 17.2at.% silicon, 79.0at.% gold, 0.3at.% copper, 0.2at.% manganese) to the bottom of the electrolytic cell to ensure After it is melted, the electrolysis device can be divided into an anode working area and a cathode working area, and a mixture of 47at.% beryllium chloride and 53at.% sodium chloride is added to the anode working area as the anode electrolyte, and 41at.% is added to the cathode working area. % beryllium chloride, 55at.% sodium chloride, 4at.% lithium oxide mixture as catholyte;

(2) Add beryllium fluoride with a purity of 90% to the anode working area, raise the temperature of the electrolytic cell to 380° C., insert the cermet anode and nickel cathode into the anode electrolyte and the cathode electrolyte respectively, power on and electrolyze, and control the cathode voltage to - 1.95V (vs NHE), electrolysis for 8 hours, solid metal beryllium was obtained at the cathode, and the purity of the solid metal beryllium obtained by analysis was 99.8%.

Claims (9)

1. A method for preparing metal beryllium by low-temperature molten salt electrolysis is characterized in that, adopting a low-temperature liquid alloy to connect an anode work area and a cathode work area in an isolated state, the beryllium-containing raw material enters the anode work area, and is electrolyzed by an electric field at a low temperature, The beryllium-containing raw material is reduced to metal beryllium and dissolved into the low-temperature liquid alloy. At the same time, the beryllium in the low-temperature liquid alloy is oxidized into beryllium ions in the cathode working area, and then the solid metal beryllium is deposited by electron reduction at the cathode; the low temperature <600 ℃; the low-temperature liquid alloy contains 53-85 at.% gold, 0-38 at.% beryllium, 0-20 at.% silicon, and may contain one or more of copper, silver, and manganese. The bottom is liquid. 2. the method for preparing metal beryllium by low temperature molten salt electrolysis according to claim 1, is characterized in that, comprises the following steps: (1) Divide the electrolytic cell into an anode working area and a cathode working area. Both the anode working area and the cathode working area contain electrolyte, and the bottom of the electrolytic cell also contains a low-temperature liquid alloy; the electrolyte in the anode working area and the cathode working area They are not in contact with each other but connected by the low-temperature liquid alloy at the bottom of the electrolytic cell; (2) Add beryllium-containing raw materials into the anode working area, then insert the anode and cathode in the anode working area and cathode working area respectively, and electrify at low temperature, and the beryllium-containing raw materials are reduced to metal at the interface between the electrolyte and the low-temperature liquid alloy in the anode working area The beryllium is dissolved into the cryogenic liquid alloy, and at the same time, the beryllium in the cryogenic liquid alloy is oxidized into beryllium ions at the interface between the cryogenic liquid alloy and the cathode working area electrolyte, enters the cathode electrolyte, and is reduced to metal beryllium on the surface of the cathode. 3. The method for preparing beryllium metal by low-temperature molten salt electrolysis according to claim 1 or 2, characterized in that, the beryllium-containing raw material is at least one of beryllium oxide, beryllium fluoride, and beryllium chloride, and the beryllium-containing raw material Purity≥50%. 4. the method for preparing metal beryllium by low temperature molten salt electrolysis according to claim 1, is characterized in that, contains 54-81 at.% gold, 0.1-38 at.% beryllium, 6-18 at.% in the described low temperature liquid alloy .%silicon. 5. The method for preparing metal beryllium by low-temperature molten salt electrolysis according to claim 1 or 2 is characterized in that the electrolysis process control mode is one or more of control current and control voltage; when controlling current, the current density is 0.01- 1.0 A/cm ² , when the voltage is controlled, the cathode voltage is ≤-2.5 V vs NHE. 6. The method for preparing metal beryllium by low-temperature molten salt electrolysis according to claim 2, characterized in that, the electrolyte in the anode work area and the cathode work area is made up of molten salt electrolyte and auxiliary agent, and the auxiliary agent addition ≤ 10 at .%. 7. The method for preparing metal beryllium by low-temperature molten salt electrolysis according to claim 6, wherein the molten salt electrolyte is lithium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, beryllium fluoride, chlorine Lithium chloride, sodium chloride, potassium chloride, rubidium chloride, cesium chloride, beryllium chloride, magnesium chloride, calcium chloride, strontium chloride, barium chloride, lanthanum chloride, praseodymium chloride, scandium chloride, chloride At least one of neodymium, samarium chloride, thorium chloride, lithium bromide, sodium bromide, potassium bromide, rubidium bromide, cesium bromide, lithium iodide, sodium iodide, potassium iodide, rubidium iodide, cesium iodide ; The auxiliary agent is at least one of lithium oxide, sodium oxide, potassium oxide, beryllium oxide, magnesium oxide, calcium oxide, and barium oxide. 8. the method for preparing metal beryllium by low-temperature molten salt electrolysis according to claim 2 is characterized in that, the anode is a kind of inert anode and active anode; the cathode is platinum, gold, iron, silver, aluminum, At least one of copper, barium, cobalt, chromium, mercury, molybdenum, nickel and graphite. 9. the method for preparing metal beryllium by low-temperature molten salt electrolysis according to claim 8 is characterized in that, the inert anode material is at least one of alloys and cermets; the active anode material is graphite, semi At least one of graphite, graphite, graphene, carbon nanotubes, and carbon fibers.

Images