Equipment and method for efficiently separating impurities and preparing high-purity magnesium

Abstract

The invention provides equipment and a method for efficiently separating impurities and preparing high-purity magnesium, and belongs to the technical field of preparation of high-purity metal materials. A device for efficiently separating impurities and preparing high-purity magnesium comprises a melting furnace used for melting raw materials and storing molten raw materials and connected with a separation furnace through a pipeline; the separation furnace is sequentially provided with a first heating area, a second heating area and a low-boiling-point impurity condensation area from bottom to top, and a crucible is placed in the first heating area and used for containing molten raw materials; a detachable filtering material is mounted between the first heating area and the second heating area; the second heating area is connected with the low-boiling-point impurity condensation area through a pipeline; the pressure control system comprises a gas storage tank and a vacuum pump and is used for adjusting the pressure in the separation furnace; and the first heating area, the second heating area and the low-boiling-point impurity condensation area are respectively provided with a collecting device. According to the technology, efficient separation of magnesium and high / low-boiling-point impurities is achieved by accurately controlling the evaporation temperature and the steam filtering and condensing process.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of high-purity metal material preparation, and particularly relates to an equipment and method for efficiently separating impurities and preparing high-purity magnesium. BACKGROUND

[0002] As the lightest structural metal, magnesium can be used to replace steel and aluminum materials on a large scale and is widely applied to the fields of new energy vehicles, aerospace, rail transportation, electronic equipment, national defense and military industry, and plays an important role in promoting energy saving and emission reduction. In addition, with the continuous development of the field of new materials, magnesium-based hydrogen storage materials, battery materials, medical materials and semiconductor materials and other emerging magnesium-based materials show excellent performance and broad application prospects. However, the actual application process shows that once the trace impurities or impurity combinations in the magnesium product exceed a certain limit, the corrosion resistance, biocompatibility, tensile strength, yield stress and elongation of the magnesium product will be greatly damaged. For example, when the iron content exceeds 170 ppm, the corrosion rate of magnesium will increase exponentially, and when the nickel and copper contents are higher than 5 ppm and 100 ppm, the corrosion rate of magnesium will increase and the biocompatibility of magnesium will decrease. When the contents of strontium, yttrium, cerium and gadolinium exceed a certain amount, the strength and elongation of the magnesium material will be affected. Therefore, it is very important to develop a method for efficiently separating impurities in magnesium for improving the performance of magnesium-based materials and large-scale application of magnesium.

[0003] Patent 202010963753.8 proposes a device and method for semi-continuous preparation of high-purity magnesium with different purities. At least three communicating reaction chambers are arranged in a high-temperature reaction box, the temperature of the reaction chambers is controlled at 655-800 DEG C, the system pressure is 500 Pa-1000 Pa, and 5N purity magnesium can be collected in the third reaction chamber corresponding to the condenser. By controlling the material flow and volatilization process, the corresponding purity condensate can be collected above the corresponding temperature material chamber, but the number of reaction chambers required is greater than or equal to three, and the vapor movement and condensation process cannot be effectively controlled, resulting in a complex device and limited impurity separation degree.

[0004] Patent 202010944755.2 proposes a method for producing high-purity magnesium from industrial magnesium ingots. The method uses crude magnesium or magnesium ingots conforming to the national standard GB / T3499-2011 as raw materials, sets a primary distillation furnace and a secondary distillation furnace, controls the furnace pressure at 3.03x10 4 -9.11x10 4 Pa, and the distillation temperature is between 650-1000 DEG C. According to whether the zinc content in the magnesium ingot meets the Mg9999 requirement in GB / T3499-2011, one or two distillation operations are performed to obtain 4N magnesium liquid. The method has high requirements for the composition of the raw materials, usually requires two distillation purification processes, and has the problems of complex equipment and long production process.

[0005] Patent 201711157115.1 proposes a method for producing ultra-high purity magnesium from industrial pure magnesium, controlling the system pressure 1.0-10Pa, the raw material distillation temperature 700-850℃, by adjusting the circulating water temperature and flow rate, the three-stage condensation zone temperature is controlled at 500-600℃, 350-500℃, 250-350℃, respectively, and 99.996wt% high purity magnesium is collected in the middle stage condensation zone. This method can effectively control the raw material distillation and metal vapor condensation process, but the vapor movement process is not controlled, and the wide condensation temperature control range lacks selection basis, which makes it difficult to further improve the product purity.

[0006] Patent 201711001069.6 proposes a high-purity magnesium semi-continuous distillation production method, which sets up a melting pot, an intermediate pot, a crude distillation tower, a distillation tower and other devices, and realizes the removal of high-boiling-point impurities by controlling the crude distillation tower temperature at about 1050℃. Then, magnesium and low-boiling-point impurity mixture is distilled to remove low-boiling-point impurities. However, this method does not consider the removal of elements similar to the saturation vapor pressure of magnesium, and the equipment structure is relatively complex and the operation is relatively cumbersome.

[0007] From the above patents, it can be seen that most of the existing methods for preparing high-purity magnesium require the setting of multiple reaction bins or multiple distillation towers, which are essentially multiple distillations. There are problems of long process flow, complex equipment, and low yield of high-purity magnesium. In addition, the purification process mostly only controls the distillation temperature, ignoring the important influence of vapor movement and condensation process on purification, and there is no clear basis for selecting basic parameters such as distillation temperature, system pressure and distillation time, resulting in incomplete separation of impurities and difficulty in breaking through the product purity of 5N. The purpose of the present patent is to provide a device and method for efficiently separating impurities and preparing high-purity magnesium to solve the problems of complex equipment, long process flow, no basis for production condition selection and incomplete separation of impurities in the prior art. SUMMARY

[0008] The technical problem to be solved by the present application is to provide a device and method for efficiently separating impurities and preparing high-purity magnesium to solve the problems of complex equipment, long process flow, no basis for production condition selection and incomplete separation of impurities in the prior art.

[0009] In order to achieve the purpose of the present application, the technical scheme adopted is as follows: a device for efficiently separating impurities and preparing high-purity magnesium, comprising:

[0010] A melting furnace is used for raw material melting and molten raw material storage, and is connected to a separation furnace through a pipeline;

[0011] The separation furnace is sequentially provided with a first heating zone, a second heating zone and a low-boiling-point impurity condensing zone from bottom to top, wherein:

[0012] A crucible is placed in the first heating zone for accommodating the molten raw material;

[0013] A detachable filter material is installed between the first heating zone and the second heating zone;

[0014] The second heating zone and the low-boiling-point impurity condensing zone are connected through a pipeline;

[0015] A pressure control system comprising a gas storage tank and a vacuum pump is used for adjusting the pressure in the separation furnace;

[0016] Preferably, the first heating zone, the second heating zone and the low-boiling-point impurity condensing zone are respectively provided with collecting devices, the collecting device of the first heating zone is a high-boiling-point impurity collector, the corresponding collecting device of the second heating zone is a high-purity magnesium collector, and the corresponding collecting device of the low-boiling-point impurity condensing zone is a low-boiling-point impurity collector.

[0017] Preferably, the melting furnace adopts resistance heating and is connected with the separation furnace through a pipeline, a high-temperature melt valve and a melt flow meter.

[0018] Preferably, the filter material is a porous filter material made of metal, semi-metal or ceramic material and is used for adsorbing impurities with a saturated vapor pressure similar to that of magnesium.

[0019] Preferably, the collecting structure of the low-boiling-point impurity condensing zone is obliquely arranged, and the outlet of the pipeline connecting the second heating zone and the low-boiling-point impurity condensing zone is higher than the lowermost collecting platform of the low-boiling-point impurity condensing zone.

[0020] Preferably, the collecting structure of the lowermost layer of the second heating zone is obliquely arranged to avoid the backflow of condensed magnesium to the first heating zone.

[0021] Further preferably, the pressure control system further comprises a gas flow meter and a valve for dynamically adjusting the pressure in the separation furnace, and the gas filled is an inert gas which does not react with magnesium.

[0022] Another technical scheme of the present application is a method for efficiently separating impurities and preparing high-purity magnesium, which adopts the above-mentioned device and comprises the following steps:

[0023] S1. Detecting the composition of the raw material, calculating the temperature at which the difference between the saturated vapor pressures of magnesium and impurities is maximum as the temperature condition of the first heating zone, calculating the time required for the complete volatilization of magnesium as the holding time, and calculating the initial condensing temperature of the volatile elements as the temperature condition of the second heating zone;

[0024] S2. Melting the raw material in the melting furnace and then inputting it into the crucible in the first heating zone of the separation furnace;

[0025] S3. Controlling the first heating zone to operate at the calculated temperature, so that high-boiling impurities remain in the crucible and low-boiling impurities and magnesium vapor move upward;

[0026] S4. Passing the vapor through a filtering material to adsorb impurities with a saturated vapor pressure close to that of magnesium;

[0027] S5. Controlling the second heating zone to operate at the condensation temperature of magnesium, so that magnesium vapor condenses and low-boiling impurities vapor enter the low-boiling impurities condensation zone;

[0028] S6. Collecting the materials from the first heating zone, the second heating zone and the low-boiling impurities condensation zone, respectively;

[0029] S7. Repeating the above steps to achieve continuous purification.

[0030] Preferably, the saturated vapor pressure calculation formula in step S1 is:

[0031] lg p * = AT -1 + B lg T + CT + D

[0032] wherein A, B, C and D are the volatilization constants of the substance.

[0033] The volatilization rate calculation formula is:

[0034]

[0035] wherein a is the evaporation coefficient of the substance, p pa is the saturated vapor pressure of the substance, M is the atomic mass of the substance, and T is the temperature.

[0036] The condensation temperature calculation formula is:

[0037] Δ r G θ = -RT ln (P g / p θ )

[0038] wherein T is the temperature, p g is the saturated vapor pressure of the substance at the corresponding temperature, and p θ is the standard atmospheric pressure.

[0039] Preferably, the raw material includes crude magnesium, magnesium ingot, magnesium alloy or magnesium-containing waste.

[0040] Further preferably, the high-boiling impurities include Ti, Si, Ni, MgCl2, CaCl2 or MgO; the low-boiling impurities include K, Na or Zn; and the impurities with a saturated vapor pressure close to that of magnesium include Ca, Mn or Pb.

[0041] Compared with the prior art, the present application achieves the following technical effects:

[0042] (1) Theoretical innovation: The precise selection model of experimental conditions such as distillation temperature, distillation time, and vapor condensation temperature is established by taking more accurate theoretical calculation as the basis for experimental condition selection, which can ensure that magnesium in the raw material is completely volatilized, and high-boiling-point impurities are completely enriched in the first heating zone, and low-boiling-point impurities completely enter the low-boiling-point impurity condensation zone, achieving accurate separation of impurities while improving the yield of high-purity magnesium, and providing a parameter selection basis for separation and purification of raw materials of any composition.

[0043] (2) Equipment innovation: The processes of material volatilization and separation, vapor filtration and purification, and vapor condensation and separation are integrated into one device, avoiding the problems of device complexity and increased energy consumption caused by multiple reaction chambers, multiple distillation columns, and multiple temperature control devices in existing devices, achieving "full-process" control and "short-process" production of high-purity magnesium. Through the connection of the separation furnace and the melting furnace, continuous production can be realized.

[0044] (3) Method innovation: Through theoretical innovation and equipment design, accurate control of material volatilization, vapor movement, and vapor condensation is achieved, shortening the preparation process of high-purity magnesium, simplifying the high-purity magnesium preparation equipment, and achieving the removal of "all elements" of impurity elements with saturated vapor pressure greater than, less than, or similar to magnesium, which can be applied to the separation and purification of raw materials with various impurity compositions, such as crude magnesium, magnesium ingots, and waste magnesium alloys. The results show that the high-purity magnesium prepared by the present application has higher purity than existing products. BRIEF DESCRIPTION OF DRAWINGS

[0045] For ease of illustration, the present application is described in detail by the following specific embodiments and drawings.

[0046] Figure 1 The figure is a structural schematic diagram of the device of the present application.

[0047] In the figure: 1 - melting furnace; 2 - high-temperature melt valve; 3 - melt flowmeter; 4 - vacuum pump; 5 - gas flowmeter; 6 - first heating zone; 7 - low-boiling-point impurity condensation zone; 8 - low-boiling-point impurity collector; 9 - second heating zone; 10 - high-purity magnesium collector; 11 - crucible; 12 - high-boiling-point impurity collector; 13 - pressure control system. DETAILED DESCRIPTION

[0048] The following are specific embodiments of the present application and further describe the technical solutions of the present application in conjunction with the drawings, but the present application is not limited to these embodiments; in the following description, specific details such as specific configurations are provided only to help a comprehensive understanding of the embodiments of the present application. Therefore, those skilled in the art should understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application.

[0049] It should be noted that the embodiments and features in the present application can be combined with each other without conflict.

[0050] The present application provides a device for efficiently separating impurities and preparing high-purity magnesium, comprising:

[0051] A melting furnace 1 is used for melting raw materials and storing the molten raw materials, and is connected to the separation furnace through a pipeline;

[0052] The separation furnace is sequentially provided with a first heating zone 6, a second heating zone 9 and a low-boiling-point impurity condensing zone 7 from bottom to top, wherein:

[0053] A crucible 11 is placed in the first heating zone 6 for accommodating the molten raw materials;

[0054] A detachable filter material is installed between the first heating zone 6 and the second heating zone 9;

[0055] The second heating zone 9 and the low-boiling-point impurity condensing zone 7 are connected through a pipeline;

[0056] A pressure control system 13 comprising a gas storage tank and a vacuum pump 4 is used for adjusting the pressure in the separation furnace;

[0057] Preferably, the first heating zone 6, the second heating zone 9 and the low-boiling-point impurity condensing zone 7 are respectively provided with collecting devices, the collecting device of the first heating zone 6 is a high-boiling-point impurity collector 12, the corresponding collecting device of the second heating zone 9 is a high-purity magnesium collector 10, and the corresponding collecting device of the low-boiling-point impurity condensing zone 7 is a low-boiling-point impurity collector 8.

[0058] Preferably, the melting furnace 1 adopts resistance heating and is connected to the separation furnace through a pipeline, a high-temperature-resistant melt valve 2 and a melt flow meter 3.

[0059] Preferably, the filter material is a porous filter material made of metal, semi-metal or ceramic material, which is used for adsorbing impurities with a saturated vapor pressure similar to that of magnesium.

[0060] Preferably, the collecting structure of the low-boiling-point impurity condensing zone 7 is obliquely arranged, and the outlet of the pipeline connecting the second heating zone 9 and the low-boiling-point impurity condensing zone 7 is higher than the lowermost collecting platform of the low-boiling-point impurity condensing zone 7.

[0061] Preferably, the collecting structure of the lowermost layer of the second heating zone 9 is obliquely arranged to avoid the backflow of condensed magnesium to the first heating zone 6.

[0062] Further preferably, the pressure control system further comprises a gas flow meter 5 and a valve for dynamically adjusting the pressure in the separation furnace, and the gas filled is an inert gas which does not react with magnesium.

[0063] The application also provides a method for separating impurities and preparing high-purity magnesium, which comprises the following steps by using the above device:

[0064] S1. Detecting the composition of raw materials, calculating the temperature at which the difference between the saturated vapor pressures of magnesium and impurities is the largest as the temperature condition of the first heating zone 6, calculating the time required for the complete volatilization of magnesium as the holding time, and calculating the initial condensation temperature of volatile elements as the temperature condition of the second heating zone 9;

[0065] S2. Melting the raw materials in the melting furnace 1 and then inputting them into the crucible 11 in the first heating zone 6 of the separation furnace;

[0066] S3. Controlling the first heating zone 6 to operate at the calculated temperature, so that high-boiling-point impurities remain in the crucible 11 and low-boiling-point impurities and magnesium vapor move upward;

[0067] S4. Making the vapor pass through the filtering material to adsorb impurities with a saturated vapor pressure close to that of magnesium;

[0068] S5. Controlling the second heating zone 9 to operate at the condensation temperature of magnesium, so that magnesium vapor is condensed and low-boiling-point impurity vapor enters the low-boiling-point impurity condensation zone 7;

[0069] S6. Collecting the materials in the first heating zone 6, the second heating zone 9 and the low-boiling-point impurity condensation zone 7, respectively;

[0070] S7. Repeating the above steps to realize continuous purification.

[0071] The saturated vapor pressure calculation formula in step S1 is as follows:

[0072] lg p * =AT -1 +B lg T+CT+D

[0073] Wherein, A, B, C and D are the volatilization constants of the substance.

[0074] The volatilization rate calculation formula is as follows:

[0075]

[0076] Wherein, α is the evaporation coefficient of the substance, p pa is the saturated vapor pressure of the substance, M is the atomic mass of the substance, and T is the temperature.

[0077] The condensation temperature calculation formula is as follows:

[0078] Δ r G θ =-RTln(P g / p θ )

[0079] Wherein, T is the temperature, and pg P0 is the saturated vapor pressure of the substance at the corresponding temperature, p θ P0 is the saturated vapor pressure of the substance at the corresponding temperature, p

[0080] Preferably, the raw material comprises crude magnesium, magnesium ingot, magnesium alloy or magnesium-containing waste.

[0081] Further preferably, the high-boiling-point impurities comprise Ti, Si, Ni, MgCl2, CaCl2 or MgO; the low-boiling-point impurities comprise K, Na or Zn; and the impurities having a saturated vapor pressure similar to that of magnesium comprise Ca, Mn or Pb.

[0082] Example 1

[0083] First step, raw material analysis. The Pijiang method was used to analyze the magnesium ingot as the raw material, and the composition of the raw material was obtained as shown in Table 1:

[0084] Table 1: Composition of the raw material

[0085]

[0086] Second step, parameter selection. According to the composition of the raw material, the saturated vapor pressures of each element were calculated, and the temperature conditions when the difference in saturated vapor pressure of each element was the largest were determined. It was calculated that when the temperature was 923-1073 K, the difference in saturated vapor pressure between magnesium and high-boiling-point impurities was large, which was beneficial to the separation of such impurities. The composition analysis and calculation results of the raw material showed that the impurities having a saturated vapor pressure similar to that of magnesium and less than that of magnesium were calcium and lead. Therefore, according to the properties of calcium and lead, copper-based and titanium-based filter materials were selected for targeted removal.

[0087] The temperature of the first heating zone was selected to be 1023 K. According to the maximum evaporation rate of the elements and the mass of the melt (5 kg) entering the crucible, it was calculated that the time required for complete evaporation of magnesium at this experimental temperature was 8.96 minutes.

[0088] If magnesium is to be distilled and purified in a liquid state, the system pressure needs to be greater than 376 Pa. Therefore, the system pressure was controlled to be 1000 Pa. Under this condition, the condensation temperature of the easily volatile elements was calculated. The condensation temperatures of Mg, Zn, Na and K metal vapors were 980.01 K, 854.92 K, 807.34 K and 701.14 K, respectively.

[0089] Third step, production preparation. The crucible was placed in the first heating zone, and copper-based and titanium-based filter materials were installed between the first heating zone and the second heating zone. The temperature of the first heating zone was set to 1073 K, and the temperature of the second heating zone was set to 980 K. The holding time was 8.96 minutes.

[0090] Fourth step, production operation. Keep the feed valve closed, melt the raw material in the melting furnace; open the vacuum pump, when the pressure in the separation furnace reaches below 10 Pa, fill the protective gas to 1000 Pa.

[0091] Fifth step, after the raw material in the melting furnace is completely melted, open the feed valve, and after 5 kg of melt enters the crucible in the first heating zone, close the feed valve. At this time, the melt in the crucible begins to evaporate, among which the impurities with a saturation vapor pressure much lower than magnesium remain in the crucible, and the impurities with a saturation vapor pressure lower than magnesium but close to magnesium (calcium, lead) evaporate in small amounts and are adsorbed and removed by the filter material during upward movement. With the continuous upward movement of the vapor, elements with a larger saturation vapor pressure (Mg, Zn, Na, K) enter the second heating zone. Since the temperature of the second heating zone can only make magnesium vapor condense, the metal vapor of Zn, Na, and K further moves upward and enters the low-boiling-point impurity condensing zone through the pipeline.

[0092] Sixth step, when the melt in the first heating zone, the second heating zone, and the low-boiling-point impurity condensing zone accumulates to a certain amount, open the valve of the corresponding collection device to make it enter the collection device. Open the valve between the melting furnace and the separation furnace to make a certain amount of raw material enter the separation furnace, and repeat the above operation.

[0093] Seventh step, after the production is completed, take a certain amount of sample in the high-purity magnesium collector for analysis and detection, and the obtained results are shown in Table 2:

[0094] Table 2 Purity detection of magnesium in the high-purity magnesium collector

[0095]

[0096] Example 2

[0097] First step, raw material analysis: the magnesium ingot obtained by the Pijiang method is used as the raw material, and the raw material is analyzed and detected to obtain the composition of the raw material as shown in Table 3:

[0098] Table 3 Composition detection of raw material

[0099]

[0100] Second step, parameter selection: according to the composition of the raw material, the saturation vapor pressure of each element is calculated, and the temperature condition when the difference value of the saturation vapor pressure of each element is the largest is determined. Through calculation, when the temperature is 923-1073 K, the difference value of the saturation vapor pressure of magnesium and high-boiling-point impurities is large, which is beneficial to the separation of such impurities. At this time, the impurities with a saturation vapor pressure close to magnesium and less than magnesium are calcium and a small amount of lead, and the extremely small amount of lead can be ignored. Therefore, according to the properties of calcium, copper-based filter material is selected for targeted removal.

[0101] The temperature of the first heating zone is selected as 1073 K. According to the maximum evaporation rate of the elements and the mass of the melt (10 kg) entering the crucible, the time required for complete evaporation of magnesium at this experimental temperature is calculated as 8.88 minutes.

[0102] If magnesium is to be distilled in liquid form, the system pressure needs to be greater than 376 Pa. Therefore, the system pressure is controlled at 2000 Pa. Under this condition, the condensation temperature of the volatile elements is calculated. The condensation temperatures of Mg, Zn, Na and K metal vapors are 1020.49 K, 889.63 K, 845.75 K and 736.37 K, respectively.

[0103] In the third step, production preparation, the crucible is placed in the first heating zone, and a copper-based filter material is installed between the first heating zone and the second heating zone. The temperature of the first heating zone is set to 1073 K, and the temperature of the second heating zone is set to 1020 K. The holding time is 8.88 minutes.

[0104] In the fourth step, production operation, the feed valve is kept closed, and the raw materials are added to the melting furnace for melting. The vacuum pump is started, and when the pressure in the separation furnace reaches below 10 Pa, the protective gas is filled to 2000 Pa.

[0105] In the fifth step, after the raw materials in the melting furnace are completely melted, the feed valve is opened, and 10 kg of melt is introduced into the crucible in the first heating zone. At this time, the melt in the crucible of the first heating zone begins to evaporate. The impurities with a saturation vapor pressure much lower than that of magnesium remain in the crucible, and a small amount of impurities with a saturation vapor pressure lower than that of magnesium but close to that of magnesium (calcium and lead) evaporate and are adsorbed and removed by the filter material during upward movement. As the vapor continues to move upward, elements with a higher saturation vapor pressure (Mg, Zn, Na, and K) enter the second heating zone. Since the temperature of the second heating zone can only cause magnesium vapor to condense, the metal vapors of Zn, Na, and K further move upward and enter the low-boiling-point impurity condensation zone through the pipeline.

[0106] In the sixth step, when the melt in the first heating zone, the second heating zone, and the low-boiling-point impurity condensation zone accumulates to a certain amount, the valve of the corresponding collection device is opened to allow it to enter the collection device. The valve between the melting furnace and the separation furnace is opened to allow a certain amount of raw materials to enter the separation furnace, and the above operation is repeated.

[0107] In the seventh step, after the production is completed, a certain amount of sample is taken from the high-purity magnesium collector for analysis and detection. The results are shown in Table 4.

[0108] Table 4 Purity detection of magnesium in the high-purity magnesium collector

[0109]

[0110] Those skilled in the art can make various modifications or supplements to the specific embodiments described or adopt similar ways to replace, but will not deviate from the inventive concept of the present application or beyond the scope defined by the appended claims.

Claims

1. An apparatus for efficiently separating impurities and preparing high-purity magnesium, characterized in that, include: A melting furnace (1) is used for melting raw materials and storing molten raw materials, and is connected to a separation furnace via a pipeline; The separator furnace is configured from bottom to top with a first heating zone (6), a second heating zone (9), and a low-boiling-point impurity condensation zone (7), wherein: A crucible (11) is placed in the first heating zone (6) to hold the molten raw material; A removable filter material is installed between the first heating zone (6) and the second heating zone (9); The second heating zone (9) and the low-boiling-point impurity condensation zone (7) are connected by a pipe; The pressure control system (13), including a gas storage tank and a vacuum pump (4), is used to regulate the pressure inside the separator furnace; The first heating zone (6), the second heating zone (9), and the low-boiling-point impurity condensation zone (7) are each equipped with a collection device.

2. The device according to claim 1, characterized in that, The melting furnace (1) is heated by resistance and is connected to the separation furnace through pipes, valves (2) and melt flow meters (3).

3. The device according to claim 1, characterized in that, The filter material is a porous filter material made of metal, semi-metal, or ceramic, used to adsorb impurities with a saturated vapor pressure similar to that of magnesium.

4. The device according to claim 1, characterized in that, The collection structure of the low-boiling-point impurity condensation zone (7) is inclined, and the outlet of the pipe connecting the second heating zone (9) and the low-boiling-point impurity condensation zone (7) is higher than the lowest collection platform of the low-boiling-point impurity condensation zone (7).

5. The device according to claim 1, characterized in that, The collection structure at the bottom of the second heating zone (9) is inclined to prevent condensed magnesium from flowing back to the first heating zone (6).

6. The device according to claim 1, characterized in that, The pressure control system also includes a gas flow meter (5) and valves for dynamically regulating the pressure inside the separation furnace. The gas introduced is an inert gas that does not chemically react with magnesium.

7. A method for efficiently separating impurities and preparing high-purity magnesium, characterized in that, Using the device according to any one of claims 1-6, the steps include: S1. Detect the raw material composition, calculate the temperature at which the difference between the saturated vapor pressure of magnesium and impurities is the largest as the temperature condition of the first heating zone (6), calculate the time required for magnesium to completely volatilize as the heat preservation time, and calculate the initial condensation temperature of volatile elements as the temperature condition of the second heating zone (9). S2. After the raw material is melted in the melting furnace (1), it is fed into the crucible (11) of the first heating zone (6) of the separation furnace; S3. Control the first heating zone (6) to operate at the calculated temperature so that high-boiling-point impurities remain in the crucible (11), while low-boiling-point impurities and magnesium vapor move upward. S4. Steam passes through the filter material, adsorbing impurities with a saturated vapor pressure similar to that of magnesium; S5. Control the second heating zone (9) to operate at the magnesium condensation temperature, so that magnesium vapor condenses and low-boiling-point impurity vapor enters the low-boiling-point impurity condensation zone (7); S6. Collect the materials from the first heating zone (6), the second heating zone (9), and the low-boiling-point impurity condensation zone (7) respectively; S7. Repeat the above steps to achieve continuous purification.

8. The method according to claim 7, characterized in that, The formula for calculating the saturated vapor pressure in step S1 is: lg p * =AT -1 +B lg T+CT+D The formula for calculating the evaporation rate is: The formula for calculating condensation temperature is: Δ r G θ =-RTln(P g / p θ )。 9. The method according to claim 7, characterized in that, The raw materials include crude magnesium, magnesium ingots, magnesium alloys, or magnesium-containing waste.

10. The method according to claim 7, characterized in that, The high-boiling-point impurities include Ti, Si, Ni, MgCl2, CaCl2, or MgO; the low-boiling-point impurities include K, Na, or Zn; and the impurities with saturated vapor pressures similar to magnesium include Ca, Mn, or Pb.

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