Method for synchronously recovering germanium tetrachloride from metal-state regenerated germanium raw material through oxychlorination
By integrating oxidation and chlorination distillation through simultaneous oxychlorination, the problems of lengthy processes, low germanium recovery rates, and high energy consumption in existing technologies have been solved, achieving efficient and economical germanium tetrachloride recovery.
Patent Information
- Application Number
- CN202511984135.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-03-17
AI Technical Summary
The existing technology for recovering germanium tetrachloride from metallic recycled germanium raw materials is lengthy and complex, with low germanium recovery rate, long production cycle, large consumption of auxiliary raw materials, and high energy consumption, resulting in low efficiency.
The simultaneous oxychlorination method integrates oxidation and chlorination distillation into the same reaction equipment. By adding hydrogen peroxide solution dropwise in stages and using the heat of reaction to distill germanium tetrachloride, intermediate steps and external heating are avoided, thus achieving a one-step continuous reaction.
It improves the direct recovery rate of germanium tetrachloride, saves energy and auxiliary raw material costs, simplifies the process, and enhances production efficiency.
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Figure CN121672574A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of germanium extraction metallurgy, and in particular to a method for synchronously recovering germanium tetrachloride from metal-state regenerated germanium raw materials through oxychlorination. BACKGROUND
[0002] Germanium, as a typical rare and dispersed metal, is an important scarce strategic resource and reserve material for the country, and plays an irreplaceable key role in the fields of national defense and military industry, modern communication, aerospace and cutting-edge medical treatment, etc. Therefore, developing efficient, economical and green germanium recovery technology is of great significance for guaranteeing the safety and sustainable supply of strategic resources.
[0003] Currently, germanium tetrachloride is recovered from germanium-containing materials such as scraps, waste and germanium mud generated in the process of germanium deep processing, and the industry generally adopts the classic two-step method process of "hydrogen peroxide solution oxidation-hydrochloric acid chlorination distillation". The process flow is as shown in Figure 1 The main steps of the traditional process are as follows: first, the metal-state regenerated germanium raw material is slurried in an oxidation reaction kettle, and hydrogen peroxide solution is added dropwise under stirring for oxidation. In order to fully oxidize metallic germanium into tetravalent germanium compounds, industrial liquid alkali (such as NaOH) must be continuously added to the reaction system to maintain the reaction liquid in a weak alkaline environment (pH 8-10). After oxidation is completed, the generated solid product needs to be filtered and dried. Subsequently, the dried intermediate product is transferred to a chlorination distillation kettle, concentrated hydrochloric acid is added, and heating is performed by an external heat source to above 83°C for chlorination distillation, and finally germanium tetrachloride product is obtained through condensation.
[0004] Although this process is widely used, it has a series of inherent technical defects and economic problems, which restrict the further improvement of its efficiency and benefit, mainly reflected in: 1. Long and complex process flow: oxidation and chlorination distillation must be carried out in two independent reaction devices in two steps, involving multiple processes such as solid-liquid separation, drying, etc., which not only increases equipment investment and land occupation, but also increases operation complexity and labor intensity.
[0005] 2. Limited germanium recovery rate (direct recovery rate): each intermediate processing process (such as filtration, washing, transfer, drying) inevitably causes entrainment and loss of germanium materials, making it difficult to effectively improve the overall direct recovery rate of germanium.
[0006] 3. Long production cycle and low efficiency: it usually takes about 72 hours to complete a complete oxidation, separation, drying and chlorination distillation process, which is slow in material turnover and low in production efficiency.
[0007] 4. Large consumption of auxiliary raw materials and high cost: a large amount of industrial liquid alkali is continuously consumed in the oxidation stage to maintain the alkaline environment, increasing the cost of raw materials.
[0008] 5. High energy consumption: The chlorination distillation process requires continuous external heating to maintain the reaction temperature above 83°C, resulting in significant energy consumption and increased operating costs.
[0009] The pursuit of those skilled in the art has always been to overcome the problems of complex and lengthy processes, low direct germanium recovery rates, long production cycles, high consumption of auxiliary reagents, and low energy efficiency in traditional processes, so as to achieve more efficient, economical, energy-saving and higher direct germanium resource recovery. Summary of the Invention
[0010] To address or partially address the problems existing in related technologies, this application provides a method for the simultaneous oxychlorination recovery of germanium tetrachloride from metallic regenerated germanium raw materials. This method features a simple process flow, high direct recovery rate of germanium tetrachloride, energy saving, environmental protection, and low cost.
[0011] This application discloses a method for the simultaneous oxychlorination recovery of germanium tetrachloride from metallic recycled germanium feedstock, comprising the following steps: (1) Add metallic regenerated germanium raw material and hydrochloric acid with a concentration of 35-37% to a chlorination distillation vessel and mix to form a slurry; wherein, the amount of hydrochloric acid added is calculated according to the mass-volume ratio of metallic regenerated germanium raw material to hydrochloric acid of 1:25 to 1:30, wherein the mass unit is grams and the volume unit is milliliters; (2) Add a 30-35% hydrogen peroxide solution to the slurry, so that the hydrogen peroxide reacts with hydrochloric acid to generate an active chlorine species, which oxidizes and chlorinates metallic germanium to generate germanium tetrachloride in one step; wherein, the total amount of hydrogen peroxide solution added is calculated according to the mass-volume ratio of metallic regenerated germanium raw material to hydrogen peroxide solution of 1:4 to 1:5, where the mass unit is grams and the volume unit is milliliters; During this process: a) Add hydrogen peroxide solution using a segmented dropping method: In the initial stage, add dropwise at the first flow rate; When the temperature of the reaction system rises to 45-50°C, the dropping rate is adjusted to the second flow rate; When no black particles are observed in the solution in the reactor, the dropping rate is reduced to the third flow rate, and the dropping continues until the hydrogen peroxide solution is completely added. b) Temperature control during the reaction process: The generated germanium tetrachloride is distilled out of the reaction system using the heat of reaction released by the oxychlorination reaction; when the temperature of the reaction system reaches 78-82°C, a cooling medium is introduced into the jacket of the chlorination distillation vessel to cool it and maintain the temperature of the reaction system at 82-84°C. (3) Determination of reaction endpoint and deep distillation: a) When the solution in the reaction vessel is light yellow and a milky white flocculent substance appears on the surface of the solution, the reaction is considered complete; b) Subsequently, the cooling medium in the jacket is discharged, and a heating medium is introduced into the jacket to raise the temperature of the material in the vessel to 90-98°C and maintain it for 30-35 minutes to perform deep distillation to distill off the residual germanium tetrachloride. (4) Product collection: Condensate and collect the germanium tetrachloride distilled in steps (2) and (3).
[0012] Furthermore, the first flow rate is 6–8 ml / min; the second flow rate is 15–20 mL / min.
[0013] Furthermore, the particle size of the metallic regenerated germanium raw material is ≤200 mesh.
[0014] Furthermore, the cooling medium is water; the heating medium is steam.
[0015] The mechanism of this application is as follows: The main reactions that occur when each material is added to the distillation vessel are as follows: H₂O₂ + 2HCl = 2H₂O + 2Cl₂ (Step 1 reaction) 4Cl▪ + Ge = GeCl4 (Second step reaction) Two-step addition: 2H₂O₂ + Ge + 4HCl = 4H₂O + GeCl₄ △H 反应 =-652.8kJ (Reaction 1) 2H₂O₂= O₂ + H₂O (Reaction 2) The oxidation of metallic germanium to Ge(Ⅳ) is mainly carried out by reaction one, and a large amount of heat is generated in this reaction. The amount of metallic germanium oxidized by reaction two is very small. At the end of the reaction, reaction two is the main reaction.
[0016] In particular, during the preparation of germanium tetrachloride, the reaction is highly exothermic. Adding H2O2 all at once or too quickly can cause a sudden increase in the reaction rate, resulting in a rapid accumulation of heat, which may lead to violent boiling, a pressure spike, and an exacerbation of side reactions (such as accelerated decomposition of H2O2). Therefore, this application adopts a segmented dropwise addition strategy of "slow at the beginning, fast in the middle, and slow in the later stage".
[0017] Slow initial reaction: This facilitates the initiation of the reaction and the establishment of a stable thermal equilibrium.
[0018] Mid-term rapid reaction: After the reaction temperature rises to 45-50℃, it indicates that the system has entered a stable active reaction period. Increasing the dropping rate can match the higher reaction demand at this time and improve efficiency.
[0019] Slowing down the dropping rate in the later stage: When the disappearance of black metal particles is observed, it indicates that the main reaction is nearing completion. Reducing the dropping rate can smoothly pass through the final stage of the reaction, avoid the ineffective decomposition of excessive H2O2 at high temperature, and ensure safety and efficient utilization of materials.
[0020] Furthermore, since GeCl4 has a boiling point of 83.1℃, the reaction temperature is controlled at 82-84℃ using jacket cooling, precisely maintaining it near its boiling point. This ensures that the generated GeCl4 is distilled off immediately upon formation, shifting the reaction equilibrium to the right and thus improving the conversion rate.
[0021] Compared with the prior art, the beneficial effects of this application are as follows: 1. This application integrates the two key steps of oxidation and chlorination distillation into the same reaction apparatus, achieving a one-step continuous reaction of "simultaneous oxygen and chlorination." This design fundamentally eliminates germanium loss caused by intermediate steps such as filtration, drying, and material transfer in traditional multi-step processes. Simultaneously, the active chlorine (Cl·) with extremely high oxidation potential generated in situ by hydrogen peroxide and hydrochloric acid directly oxidizes metallic germanium. This reaction pathway is more efficient and thorough, allowing metallic germanium to be more completely converted into the target product, germanium tetrachloride (GeCl4). Therefore, this method effectively improves the direct recovery rate of germanium tetrachloride, with an average direct recovery rate reaching 98.6%.
[0022] 2. This invention utilizes the strong exothermic nature of the oxychlorination reaction, the heat of reaction being sufficient to distill the generated GeCl4 out of the reaction system. In the main stage of the reaction, no external heat source is required to provide the energy needed for distillation; only a heating medium needs to be introduced into the jacket at the end of the reaction for deep distillation separation, thus significantly saving the huge energy consumption caused by continuous external heating in traditional chlorination distillation processes.
[0023] 3. This process completely eliminates the need for continuous addition of industrial liquid alkali to maintain a weakly alkaline environment (pH 8-10) in traditional oxidation processes. This not only saves on auxiliary material costs but also avoids the generation of saline wastewater, simplifies subsequent treatment, and reduces environmental pressure and overall production costs. Attached Figure Description
[0024] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of exemplary embodiments thereof in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments thereof.
[0025] Figure 1 This is a schematic diagram of the traditional preparation process; Figure 2 This is a schematic diagram of the process flow in this application. Detailed Implementation
[0026] The embodiments of this application will now be described in more detail with reference to the examples. While embodiments of this application are shown in the examples, it should be understood that this application can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.
[0027] Example 1 This embodiment describes a method for simultaneously recovering germanium tetrachloride from metallic recycled germanium feedstock via oxychlorination. The process flow is as follows: Figure 2 As shown, it includes the following steps: Step (1) Material preparation: Weigh out the 200-mesh metallic regenerated germanium raw material and add it to the intelligent chlorination distillation vessel. Then add hydrochloric acid (analytical grade concentrated hydrochloric acid) to the intelligent chlorination distillation vessel. The amount of hydrochloric acid added is calculated according to the mass-to-volume ratio of metallic regenerated germanium raw material to hydrochloric acid of 1:30, where the mass unit is grams and the volume unit is milliliters. Add the hydrochloric acid to the chlorination distillation vessel all at once, and turn on the stirrer to stir to prevent the metallic regenerated germanium raw material from settling at the bottom of the vessel and to form a uniform slurry.
[0028] The metallic recycled germanium raw material in this embodiment is a solid recycled germanium raw material in which germanium exists in a metallic state, such as elemental or alloy form. It mainly originates from substandard materials generated during the germanium zone melting and purification process; substandard materials generated during the growth of germanium single crystals; oily and watery sawdust and germanium sludge, and germanium-containing diamond powder generated during the processing of germanium single crystals and germanium single wafers for solar cells; substandard germanium-containing materials generated during the processing of infrared germanium single wafers and germanium lenses; and substandard gallium arsenide materials for electrical targets and germanium substrates.
[0029] Step (2) Oxychlorination reaction and primary distillation: Prepare a hydrogen peroxide solution (concentration of 35%). The total amount of hydrogen peroxide solution added is calculated based on a mass-to-volume ratio of 1:5 between the metallic regenerated germanium raw material and the hydrogen peroxide solution, where mass is expressed in grams and volume in milliliters. Measure the appropriate amount of hydrogen peroxide solution and place it in a storage tank remotely controlled by a horizontal flow pump.
[0030] a) Segmented dripping control: Initial stage (first flow rate): Start the horizontal flow pump and begin adding hydrogen peroxide solution dropwise at a flow rate of 7 mL / min. The reaction begins, and the system temperature rises slowly.
[0031] Intermediate stage (second flow rate): When the temperature of the reaction system rises to 47°C, the dropping rate is increased to 17 mL / min by the control system.
[0032] Later stage (third flow rate): Continue adding dropwise and observe. When the black particles in the slurry in the vessel have basically disappeared, reduce the dropping rate to 10 mL / min (third flow rate) and continue adding dropwise until all the hydrogen peroxide solution has been added.
[0033] b) Reaction temperature control: The reaction is a strongly exothermic process. The released heat causes the system temperature to rise rapidly and begins to distill off the generated GeCl4. When the system temperature reaches 80°C, the intelligent temperature control system automatically turns on and introduces cooling water into the jacket of the reactor. By adjusting the flow rate of the cooling water, the internal temperature of the reaction system is maintained at 82~84°C. This process continues until step (3).
[0034] Step (3) Determining the reaction endpoint and deep distillation: a) Endpoint determination: After the hydrogen peroxide solution has been added dropwise, and stirring and temperature control are maintained for approximately 10 minutes, the solution in the reactor is observed to change from turbid to clear light yellow, with a small amount of white flocculent matter floating on the surface. Based on this phenomenon, it is determined that the metallic germanium has been basically completely oxidized, and the reaction is complete.
[0035] b) Deep distillation: The automatic control system closes the cooling water inlet valve and opens the drain valve to drain the cooling water from the jacket. Then, the steam valve is opened to introduce steam into the jacket for heating. The temperature of the material inside the vessel is slowly raised to 95°C and maintained at this temperature for 32 minutes to perform deep distillation, ensuring that the trace amounts of GeCl4 dissolved or entrained in the liquid phase are fully distilled off.
[0036] Step (4) Product collection: The gaseous products distilled in steps (2) and (3) were completely condensed into liquid using a condenser and collected in a receiving bottle to obtain germanium tetrachloride. Based on weighing and chemical analysis, the direct recovery rate of germanium tetrachloride obtained in this example was 98.9%.
[0037] Example 2 This embodiment describes a method for simultaneously recovering germanium tetrachloride from metallic regenerated germanium feedstock via oxychlorination, comprising the following steps: Step (1) Material preparation: Weigh out the 180-mesh metallic regenerated germanium raw material and add it to the intelligent chlorination distillation vessel. Then add hydrochloric acid to the intelligent chlorination distillation vessel. The amount of hydrochloric acid added is calculated according to the mass-to-volume ratio of metallic regenerated germanium raw material to hydrochloric acid of 1:28, where the mass unit is grams and the volume unit is milliliters. Add the hydrochloric acid to the chlorination distillation vessel at one time and turn on the stirrer to stir to prevent the metallic regenerated germanium raw material from settling at the bottom of the vessel and to form a uniform slurry.
[0038] Step (2) Oxychlorination reaction and primary distillation: Prepare a hydrogen peroxide solution (concentration of 30%). The total amount of hydrogen peroxide solution added is calculated based on a mass-to-volume ratio of metallic regenerated germanium raw material to hydrogen peroxide solution of 1:4.5, where mass is in grams and volume is in milliliters. Measure the appropriate amount of hydrogen peroxide solution and place it in a storage tank remotely controlled by a horizontal flow pump.
[0039] a) Segmented dripping control: Initial stage (first flow rate): Start the horizontal flow pump and begin adding hydrogen peroxide solution dropwise at a flow rate of 6 mL / min. The reaction begins, and the system temperature rises slowly.
[0040] Intermediate stage (second flow rate): When the temperature of the reaction system rises to 50°C, the dropping rate is increased to 20 mL / min by the control system.
[0041] Later stage (third flow rate): Continue adding dropwise and observe. When the black particles in the slurry in the vessel have basically disappeared, reduce the dropping rate to 12 mL / min (third flow rate) and continue adding dropwise until all the hydrogen peroxide solution has been added.
[0042] b) Reaction temperature control: The reaction is a strongly exothermic process, and the released heat causes the system temperature to rise rapidly, and the generated GeCl4 begins to be distilled off. When the system temperature reaches 78°C, the intelligent temperature control system automatically turns on and introduces cooling water into the jacket of the reactor. By adjusting the flow rate of the cooling water, the internal temperature of the reaction system is maintained at 82~84°C. This process continues until step (3).
[0043] Step (3) Determining the reaction endpoint and deep distillation: a) Endpoint determination: After the hydrogen peroxide solution has been added dropwise, and stirring and temperature control are maintained for approximately 10 minutes, the solution in the reactor is observed to change from turbid to clear light yellow, with a small amount of white flocculent matter floating on the surface. Based on this phenomenon, it is determined that the metallic germanium has been basically completely oxidized, and the reaction is complete.
[0044] b) Deep distillation: The automatic control system closes the cooling water inlet valve and opens the drain valve to drain the cooling water from the jacket. Then, the steam valve is opened to introduce steam into the jacket for heating. The temperature of the material inside the vessel is slowly raised to 98°C and maintained at this temperature for 30 minutes to perform deep distillation, ensuring that the trace amounts of GeCl4 dissolved or entrained in the liquid phase are fully distilled off.
[0045] Step (4) Product collection: The gaseous products distilled in steps (2) and (3) were completely condensed into liquid using a condenser and collected in a receiving bottle to obtain germanium tetrachloride. Based on weighing and chemical analysis, the direct recovery rate of germanium tetrachloride obtained in this example was 98.6%.
[0046] Example 3 This embodiment describes a method for simultaneously recovering germanium tetrachloride from metallic regenerated germanium feedstock via oxychlorination, comprising the following steps: Step (1) Material preparation: Weigh out the 150-mesh metallic regenerated germanium raw material and add it to the intelligent chlorination distillation vessel. Then add hydrochloric acid to the intelligent chlorination distillation vessel. The amount of hydrochloric acid added is calculated according to the mass-to-volume ratio of metallic regenerated germanium raw material to hydrochloric acid of 1:25, where the mass unit is grams and the volume unit is milliliters. Add the hydrochloric acid to the chlorination distillation vessel at one time, and turn on the stirrer to stir to prevent the metallic regenerated germanium raw material from settling at the bottom of the vessel and to form a uniform slurry.
[0047] Step (2) Oxychlorination reaction and primary distillation: Prepare a hydrogen peroxide solution (concentration of 30%). The total amount of hydrogen peroxide solution added is calculated based on a mass-to-volume ratio of 1:4 between the metallic regenerated germanium raw material and the hydrogen peroxide solution, where mass is expressed in grams and volume in milliliters. Measure the appropriate amount of hydrogen peroxide solution and place it in a storage tank remotely controlled by a horizontal flow pump.
[0048] a) Segmented dripping control: Initial stage (first flow rate): Start the horizontal flow pump and begin adding hydrogen peroxide solution dropwise at a flow rate of 8 mL / min. The reaction begins, and the system temperature rises slowly.
[0049] Intermediate stage (second flow rate): When the temperature of the reaction system rises to 45°C, the dropping rate is increased to 15 mL / min by the control system.
[0050] Later stage (third flow rate): Continue adding dropwise and observe. When the black particles in the slurry in the vessel have basically disappeared, reduce the dropping rate to 9 mL / min (third flow rate) and continue adding dropwise until all the hydrogen peroxide solution has been added.
[0051] b) Reaction temperature control: The reaction is a strongly exothermic process. The released heat causes the system temperature to rise rapidly and begins to distill off the generated GeCl4. When the system temperature reaches 82°C, the intelligent temperature control system automatically turns on and introduces cooling water into the jacket of the reactor to maintain the internal temperature of the reaction system at 82~84°C. This process continues until step (3).
[0052] Step (3) Determining the reaction endpoint and deep distillation: a) Endpoint determination: After the hydrogen peroxide solution has been added dropwise, and stirring and temperature control are maintained for approximately 10 minutes, the solution in the reactor is observed to change from turbid to clear light yellow, with a small amount of white flocculent matter floating on the surface. Based on this phenomenon, it is determined that the metallic germanium has been basically completely oxidized, and the reaction is complete.
[0053] b) Deep distillation: The automatic control system closes the cooling water inlet valve and opens the drain valve to drain the cooling water from the jacket. Then, the steam valve is opened to introduce steam into the jacket for heating. The temperature of the material inside the vessel is slowly raised to 90°C and maintained at this temperature for 35 minutes to perform deep distillation, ensuring that the trace amounts of GeCl4 dissolved or entrained in the liquid phase are fully distilled off.
[0054] Step (4) Product collection: The gaseous products distilled in steps (2) and (3) were completely condensed into liquid using a condenser and collected in a receiving bottle to obtain colorless and transparent germanium tetrachloride. Based on weighing and chemical analysis, the direct recovery rate of germanium tetrachloride obtained in this example was 98.3%.
[0055] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.
Claims
1. A method for simultaneously recovering germanium tetrachloride from metal-state regenerated germanium raw material by oxychlorination, characterized by, The method comprises the following steps: (1) adding metal-state regenerated germanium raw material and hydrochloric acid with a concentration of 35-37% into a chlorination distillation kettle to form a slurry; wherein the amount of the hydrochloric acid is calculated according to the mass-volume ratio of the metal-state regenerated germanium raw material to the hydrochloric acid being 1:25-1:30, wherein the unit of mass is gram and the unit of volume is milliliter; (2) adding hydrogen peroxide solution with a concentration of 30-35% into the slurry drop by drop to make the hydrogen peroxide react with the hydrochloric acid to generate active chlorine species, and the active chlorine species oxidizes and chlorinates the metal germanium to generate germanium tetrachloride in one step; wherein the total amount of the hydrogen peroxide solution is calculated according to the mass-volume ratio of the metal-state regenerated germanium raw material to the hydrogen peroxide solution being 1:4-1:5, wherein the unit of mass is gram and the unit of volume is milliliter; During the process: a) the hydrogen peroxide solution is added in a segmented dropwise manner: in the initial stage, the hydrogen peroxide solution is added at a first flow rate; when the temperature of the reaction system rises to 45-50 ℃, the dropwise addition speed is adjusted to a second flow rate; when it is observed that no black particles appear in the solution in the reaction kettle, the dropwise addition speed is reduced to a third flow rate, and the dropwise addition is continued until the hydrogen peroxide solution is added completely; b) temperature control during the reaction process: the reaction heat released by the oxychlorination reaction is used to distill the generated germanium tetrachloride out of the reaction system; when the temperature of the reaction system reaches 78-82 ℃, cooling medium is introduced into the interlayer of the chlorination distillation kettle to cool, and the temperature of the reaction system is maintained at 82-84 ℃; (3) reaction end point judgment and deep distillation: a) when the solution in the reaction kettle is light yellow, and a milky white flocculent substance is generated on the surface of the solution, it is determined that the reaction is completed; b) subsequently, the cooling medium in the interlayer is discharged, heating medium is introduced into the interlayer, the temperature of the material in the kettle is raised to 90-98 ℃ and maintained for 30-35 minutes, and deep distillation is performed to distill out the residual germanium tetrachloride; (4) product collection: the germanium tetrachloride distilled out in steps (2) and (3) is condensed and collected.
2. The method for recovering germanium tetrachloride from metal germanium according to claim 1, wherein The first flow rate is 6-8 mL / min; and the second flow rate is 15-20 mL / min.
3. A method for simultaneous recovery of germanium tetrachloride from metallo-germanium raw material by oxychlorination according to claim 1, characterized in that, The particle size of the metal-state regenerated germanium raw material is ≤200 mesh.
4. The method for recovering germanium tetrachloride from metal germanium according to claim 1, wherein The cooling medium is water; and the heating medium is steam.