Preparation method of germanium dioxide

Abstract

The invention provides a preparation method of germanium dioxide. The invention relates to a preparation method of germanium dioxide, which comprises the following steps: preparing a concentrated hydrochloric acid solution of germanium tetrachloride, and enabling the germanium tetrachloride in the mixed solution not to generate hydrolysis reaction; the mixed solution is electrolyzed, chlorine is generated by an anode, hydrogen is generated by a cathode, and the concentration of hydrochloric acid in the mixed solution is reduced; and when the concentration of the hydrochloric acid is reduced to a threshold value for promoting the germanium tetrachloride and the water to generate hydrolysis reaction, continuously reacting to enable the germanium tetrachloride and the water to react to generate germanium dioxide precipitate, and separating out the germanium dioxide precipitate after the reaction is finished. The concentration of the germanium tetrachloride is 0.76 mol / L. According to the method for preparing germanium dioxide by promoting germanium tetrachloride hydrolysis through electrolysis of concentrated hydrochloric acid, the situation that extra alkali is used for adjusting the reaction is avoided, the production cost and environmental pollution are reduced, and meanwhile the product purity and the production efficiency are improved.

Description

Technical Field

[0001] This application belongs to the technical field of inorganic chemistry, and particularly relates to a method for preparing germanium dioxide. Background Art

[0002] As a key inorganic compound, germanium dioxide plays a crucial role in modern industry and high-tech fields. It has unique physical and chemical properties, such as good optical transparency, high refractive index, and excellent semiconductor characteristics, which enable it to be widely used in many fields.

[0003] Currently, there are various methods for preparing germanium dioxide industrially. Among them, the hydrolysis method of germanium tetrachloride is a relatively common preparation method. In this method, germanium tetrachloride reacts with water to form germanium dioxide precipitate, and then through a series of processes such as filtration, washing, and drying, germanium dioxide products are obtained. However, the hydrolysis precipitation method has obvious drawbacks. On the one hand, in order to promote the hydrolysis reaction, a large amount of alkali often needs to be added to neutralize the hydrochloric acid generated in the reaction to adjust the pH value of the solution. This not only increases the raw material cost and the complexity of the process flow, but also produces a large amount of salt-containing wastewater, causing serious pollution to the environment. On the other hand, the addition of alkali may introduce impurities, affecting the purity of germanium dioxide products.

[0004] In addition, the oxidation roasting method of germanium concentrate is also a common means for preparing germanium dioxide. In this method, germanium-containing concentrate is oxidized and roasted at high temperature to convert germanium into germanium dioxide. However, this method has relatively high requirements for raw materials and requires the use of high-grade germanium concentrate. Moreover, the roasting process consumes a large amount of energy and generates a large amount of waste gas, which contains pollutants such as sulfur dioxide and dust, causing great harm to the environment. At the same time, the recovery rate of this method is relatively low, resulting in serious waste of resources. Summary of the Invention

[0005] In view of this, this application provides a method for preparing germanium dioxide by promoting the hydrolysis of germanium tetrachloride through electrolysis of concentrated hydrochloric acid, which can prepare high-purity germanium dioxide in a green, efficient, and low-cost manner.

[0006] This application provides a method for preparing germanium dioxide, including:

[0007] Preparing a concentrated hydrochloric acid solution of germanium tetrachloride so that germanium tetrachloride in the mixed solution does not undergo hydrolysis reaction;

[0008] Electrolyzing the mixed solution, chlorine gas is generated at the anode and hydrogen gas is generated at the cathode, reducing the concentration of hydrochloric acid in the mixed solution;

[0009] When the concentration of hydrochloric acid is reduced to the threshold value that promotes the hydrolysis reaction of germanium tetrachloride with water, continue the reaction to make germanium tetrachloride react with water to form germanium dioxide precipitate. After the reaction ends, separate the germanium dioxide precipitate.

[0010] Preferably, the concentration of germanium tetrachloride in the mixed solution is 0.76 mol / L.

[0011] Preferably, the mass fraction of the concentrated hydrochloric acid is 36 - 38%.

[0012] Preferably, when preparing the mixed solution, the temperature is 20 - 30 °C.

[0013] Preferably, both the anode and the cathode are platinum electrodes.

[0014] Preferably, electrolysis is carried out at a constant current density and a constant temperature, and the reaction duration is 1.5 - 12 hours.

[0015] Preferably, the current density during the electrolysis process is 200 - 400 mA / cm 2 .

[0016] Preferably, the threshold value of the concentration of the hydrochloric acid is 5.2 mol / L.

[0017] Preferably, the separation method is centrifugal separation.

[0018] Preferably, the preparation method further includes washing the separated germanium dioxide precipitate with an ethanol solution and drying it at 50 - 60 °C for 24 hours.

[0019] The method for preparing germanium dioxide by promoting the hydrolysis of germanium tetrachloride through electrolyzing concentrated hydrochloric acid provided by this application ensures that germanium tetrachloride does not undergo hydrolysis reaction exactly at the initial stage by electrolyzing the concentrated hydrochloric acid in the mixed solution. Subsequently, the hydrochloric acid concentration is reduced through electrolysis, prompting germanium tetrachloride to react spontaneously with water to form germanium dioxide, avoiding the use of additional alkali to adjust the reaction, reducing production costs and environmental pollution, while improving product purity and production efficiency. At the same time, by precisely controlling the reaction conditions and process parameters, the quality stability and consistency of the product can be effectively improved to meet the requirements for high-purity germanium dioxide in different fields. And this application promotes the hydrolysis reaction by reducing the hydrochloric acid concentration through electrolysis, reducing the generation amount of wastewater, and the generated wastewater has relatively simple components and is easy to treat. In addition, the recycling of chlorine gas and hydrogen gas also reduces the emission of harmful gases, meeting the requirements of green chemistry and sustainable development. The process of this application is relatively simple, without complex reagent addition and cumbersome pH adjustment steps, the operation is more convenient, reducing human errors and process difficulties during the production process, and is conducive to large-scale industrial production. Description of the Drawings

[0020] Figure 1 It is a two-dimensional relationship diagram of the preparation temperature and the yield of this application.

[0021] Figure 2This is a two-dimensional relationship diagram of the current density and the acquisition rate of this application.

[0022] Figure 3 This is the particle size distribution diagram of this application when the current density is 400 mA / cm 2 . Specific embodiments

[0023] The technical solutions in this application will be described in detail below. Obviously, the described embodiments are only part of the embodiments of this application, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts shall fall within the scope of protection of this application.

[0024] A method for preparing germanium dioxide includes:

[0025] S1) Prepare a concentrated hydrochloric acid solution of germanium tetrachloride. The concentration of germanium tetrachloride is 0.76 mol / L, and the mass fraction of concentrated hydrochloric acid is 36-38%, with a concentration of 5.19 mol / L. The temperature during preparation can be 20-50 °C, preferably 20-30 °C, so that germanium tetrachloride in the mixed solution does not undergo hydrolysis reaction.

[0026] S2) Electrolyze the mixed solution at a constant current density and a constant temperature. The electrodes are both platinum electrodes, and the current density is preferably 200-400 mA / cm 2 . Heat the electrolytic cell to raise the temperature of the solution in the electrolytic cell to a preset temperature. Fix the electrolysis density and electrolysis duration. The electrolytic cell can be heated by a water bath to raise the temperature of the solution in the electrolytic cell to the preset temperature, thereby accelerating the movement speed of ions, enhancing the activity of ions, and increasing the rate of the electrolysis reaction. Among them, the preset temperature can be 20-50 °C. In some specific cases, experiments are carried out at temperatures of 20 °C, 30 °C, 40 °C, and 50 °C respectively, and the current density is 200 mA / cm 2 , and draw Figure 1 . Figure 1 It shows that the temperature is negatively correlated with the acquisition rate. The greater the temperature, the lower the acquisition rate. When the temperature is 20 °C, the acquisition rate is as high as 92.83%, that is, the product purity, yield, and particle size are relatively the highest at this time. Acquisition rate = actual germanium dioxide output / theoretical germanium dioxide output.

[0027] Under the condition of maintaining the preset temperature and current density, insert electrode plates into the electrolytic cell and energize.

[0028] In this application, a constant temperature environment can be created by maintaining the temperature of the water bath constant, so that the solution in the electrolytic cell is kept at a preset temperature. Then, electrode plates are inserted into the anode chamber and the cathode chamber of the electrolytic cell respectively, and it is ensured that the electrode plates are in full contact with the solution and firmly installed to ensure that the current can pass through smoothly.

[0029] Among them, the electrode plate inserted into the anode chamber can be made of materials such as graphite and platinum, which have good electrical conductivity and corrosion resistance and can withstand the action of oxidation reactions.

[0030] Among them, the electrode plate inserted into the cathode chamber can be made of materials such as stainless steel and copper, which can promote the progress of the reduction reaction.

[0031] Chlorine gas is generated at the anode and hydrogen gas is generated at the cathode, reducing the concentration of hydrochloric acid in the mixed solution. Here, when the electrode plate is energized, under the action of the electric field, chloride ions in hydrochloric acid are consumed on the anode plate to generate chlorine gas, and hydrogen ions in hydrochloric acid are consumed on the cathode plate to generate hydrogen gas, thereby consuming the hydrochloric acid concentration and increasing the water content, promoting the hydrolysis of germanium tetrachloride, and further generating germanium dioxide, realizing the preparation of germanium dioxide. It should be noted that during the electrolysis of germanium tetrachloride, by controlling the energization time and current intensity, the reaction process and the generation amount of the product can be controlled.

[0032] Specifically, during the electrolysis of hydrochloric acid, different chemical reactions will occur at the anode and the cathode respectively. At the anode, a reaction in which Cl - loses electrons to form Cl2 occurs, and the specific reaction formula is shown in Equation (1); at the cathode, a hydrogen evolution reaction occurs at the anode, and the specific reaction formula is shown in Equation (2). The overall reaction formula of the entire electrolysis process is shown in Equation (3).

[0033] 4Cl - -4e - = Cl2 (1),

[0034] 4H2O + 4e - = 2H2 + 4OH - (2),

[0035] GeCl4 + 2H2O = GeO2 + 4HCl (3).

[0036] As one of the preferences, the concentration range of the germanium tetrachloride solution is 0.76 mol / L, the concentration of hydrochloric acid as the electrolyte solution is 5.02 mol / L, the solution volume is 25 ml, and the temperature during preparation is 20 °C. In some specific cases, experiments are carried out respectively for electrolysis densities of 50 mA / cm 2 、100 mA / cm 2 、200 mA / cm 2 、400 mA / cm 2 And plotFigure 2 。 Figure 2 It shows that the current density is positively correlated with the yield, and the greater the current density, the greater the yield. When the current density reaches 400 mA / cm 2 , the yield is as high as 95.72%, that is, the product purity and yield are the highest at this time, and the particle size distribution is more uniform. When the current density reaches 200 mA / cm 2 , the yield is as high as 92.83%. At this time, the product purity and yield are relatively high, but the particle size is the smallest.

[0037] By applying the technical solution of the present application, the mixed solution of germanium tetrachloride is injected into the anode chamber, and the electrolyte solution is injected into the cathode chamber, and an efficient reaction system is constructed by using an electrolytic cell. When electrified at a preset temperature and current density, germanium tetrachloride undergoes a directional reaction under the action of an electric field. Compared with some traditional methods that require multiple complex chemical reactions to prepare germanium dioxide, the preparation process is greatly simplified, the reaction steps are reduced, so that the synthesis of germanium dioxide can be completed in a shorter time, and the production efficiency is significantly improved. Specifically, during the electrolysis process, the reaction proceeds in a relatively stable electric field and temperature environment, and the content of intermediate product impurities generated is low, and germanium dioxide products with good crystallization and high purity can be obtained. At the same time, a large amount of expensive chemical reagents are not required during the whole preparation process, thus effectively reducing the raw material cost. At the same time, the simplified process steps also reduce the energy consumption and equipment loss during the production process, further reducing the production cost, which is beneficial to large-scale industrial production.

[0038] In some possible embodiments disclosed in the present application, during the electrolysis reaction process, the current value of the electrode sheet is maintained constant, and the voltage value of the electrode sheet is monitored in real time, and the current progress of the electrolysis reaction is judged based on the voltage value.

[0039] In the present application, by monitoring the voltage value in real time, it is possible to intuitively understand the progress of the reaction, such as whether it is close to the end point of the reaction, which helps the operator accurately grasp the reaction process and avoid overreaction or incomplete reaction.

[0040] Among them, a constant current power supply can be used to load the electrode sheet to ensure that the current passing through the electrode sheet always remains at the set value. In the electrolysis reaction, the current is used to promote the occurrence and progress of the electrolysis reaction. Setting and maintaining the current passing through the electrode sheet at a fixed value can ensure that the electrolysis reaction proceeds under a relatively stable driving force, making the electrolysis reaction reproducible and controllable.

[0041] Among them, a voltmeter or an instrument with voltage monitoring function can be used to continuously measure the voltage across the electrode plate in real time. In the electrolysis reaction, the voltage reflects information such as the thermodynamic and kinetic states of the electrochemical reaction occurring on the surface of the electrode plate. Real-time monitoring of the voltage can timely obtain the voltage changes during the electrolysis process, so as to clarify various physical and chemical changes occurring in the electrolysis reaction system.

[0042] Specifically, at the beginning of the electrolysis reaction, the concentration of reactants in the electrolysis reaction system is relatively high, and there are sufficient reactive sites on the electrode surface. At this time, the voltage is usually at a relatively low level because the reaction can proceed smoothly and the polarization degree of the electrode plate is small. As the reaction progresses, the reactants are gradually consumed, products begin to form and accumulate on the surface of the electrode plate or in the solution, and the state of the electrode plate surface and the composition of the solution are constantly changing. These will cause the polarization phenomenon of the electrode plate to gradually increase, resulting in a gradual increase in voltage. When the electrolysis reaction proceeds to a certain extent, some characteristic trends may appear in the voltage change. For example, if there are multiple reaction stages or intermediate products are generated in the electrolysis reaction system, the voltage may show stage-wise stability or fluctuations. By analyzing the characteristics of these voltage changes, it can be judged whether the reaction has entered a specific intermediate stage, whether the expected intermediate products are generated, etc., so as to understand the depth and progress of the reaction. When approaching the end point of the reaction, the concentration of reactants is already very low, a large number of reactive sites on the electrode plate surface are reduced, and the reaction rate is significantly decreased. At this time, the voltage may show a sharp change or reach a relatively stable high value. According to this change characteristic of the voltage, it can be judged whether the reaction is about to be completed, whether the reaction conditions need to be adjusted or the reaction needs to be stopped, etc.

[0043] S3) When the concentration of hydrochloric acid is reduced to the threshold value that promotes the hydrolysis reaction of germanium tetrachloride with water, which is less than or equal to 5.2 mol / L, preferably 5.2 mol / L, continue the reaction to make germanium tetrachloride react with water to form germanium dioxide precipitate. After the reaction is completed, centrifuge to separate out the germanium dioxide precipitate, wash it with an ethanol solution, and dry it at 50 - 60 °C for 24 hours.

[0044] Centrifugation can quickly and effectively separate the precipitate from the electrolyte solution. After washing, a cleaning operation can further remove the residual electrolyte solution, reaction by-products, and other impurities adhering to the surface of the precipitate. Drying can remove the moisture in the cathode precipitate.

[0045] Among them, the precipitate is mixed with other impurities such as germanium tetrachloride solution and electrolyte solution.

[0046] Among them, centrifugation is a method for separating solid-liquid mixtures. Here, a centrifuge device can be used. Compared with traditional filtration methods, the centrifuge can achieve solid-liquid separation more efficiently and quickly, reduce the separation time, improve production efficiency, and can more effectively separate fine germanium dioxide particles, which helps to improve the recovery rate and purity of the product.

[0047] Among them, washing is a method for removing some soluble impurity ions or other contaminants remaining on the surface and inside of the precipitate after centrifugation. Here, the precipitate after centrifugation can be washed by adding appropriate solvents (such as deionized water, ethanol, etc.), and these solvents can dissolve and carry away the remaining impurities. It should be noted that the washing process can adopt the method of soaking multiple times, shaking and then centrifuging to ensure that as many impurities as possible are removed and the purity of the product is improved.

[0048] Among them, drying is a method for removing moisture or other solvents from the precipitate after washing. Here, the washed cathode precipitate can be placed in an oven, and under certain temperature and time conditions, the moisture or solvent is evaporated to obtain a dry solid product. The selection of drying temperature and time needs to be determined according to the specific material properties and experimental requirements to avoid decomposition, deterioration, etc. of the product during the drying process.

[0049] In addition, in some possible embodiments disclosed in the present application, the electrode plate is configured to be successively polished, first rinsed, degreased, pickled and activated, second rinsed, and dried before being inserted into the electrolytic cell.

[0050] In the present application, through polishing, the oxide layer, burrs, and uneven parts on the surface of the electrode plate can be removed, making the surface of the electrode plate smoother and more uniform, increasing the contact area between the electrode plate and the electrolyte solution, which is beneficial to the transfer of electrons and the exchange of ions, thereby improving the efficiency of the electrolysis reaction. Through the first rinse, impurities such as metal debris generated during the polishing process can be removed, preventing metal debris and other impurities from entering the electrolytic cell and contaminating the electrolyte solution, affecting the progress of the electrolysis reaction. Through degreasing, the oil stains on the surface of the electrode plate can be thoroughly removed, ensuring good contact between the electrode plate and the electrolyte solution and enabling the electrolysis reaction to proceed smoothly. Through pickling and activation, some micro-concave and convex structures or active sites can be formed on the surface of the electrode plate, increasing the roughness and active area of the electrode plate surface, further improving the catalytic effect of the electrode plate on the electrolysis reaction, and promoting the progress of the electrolysis reaction. Through the second rinse, the acid solution and some reaction products and other impurities remaining on the surface of the electrode plate after pickling and activation can be removed, preventing the acid solution and some reaction products and other impurities from entering the electrolytic cell and changing the composition and properties of the electrolyte solution, affecting the stability of the electrolysis reaction and the purity of the product. Through drying, the moisture on the surface of the electrode plate can be removed, ensuring the stability of the concentration and properties of the electrolyte solution, and enabling the electrolysis reaction to proceed under ideal conditions.

[0051] Among them, when polishing the electrode sheet, mechanical polishing can be carried out using tools such as sandpaper and grinding wheels. According to the material and surface condition of the electrode sheet, select sandpaper or grinding wheels of appropriate fineness and polish gradually from coarse to fine to achieve the desired surface finish. Chemical polishing or electrolytic polishing methods can also be used to dissolve the microscopic protrusions on the surface of the electrode sheet through chemical reactions or electrochemical reactions to achieve a flat and smooth surface.

[0052] Among them, deionized water can be used to rinse the electrode sheet for the first time. Specifically, the electrode sheet can be immersed in deionized water and assisted by an ultrasonic cleaner for cleaning. Utilize the cavitation effect of ultrasonic waves to more thoroughly remove the tiny impurities on the surface. Or use equipment such as a high-pressure water gun to rinse the surface of the electrode sheet with a water flow at a certain pressure to wash away the impurities.

[0053] Among them, when degreasing the electrode sheet, organic solvents can be used for degreasing. For example, soak the electrode sheet in organic solvents such as acetone and ethanol, and utilize the solubility of organic solvents in grease to dissolve and remove the grease. Alkaline degreasing agents can also be used. Through the saponification reaction of alkali and grease, the grease is converted into substances soluble in water and then rinsed off with water. Ultrasonic degreasing can also be adopted. Place the electrode sheet in an ultrasonic cleaning tank containing a degreasing agent, and utilize the mechanical action and cavitation effect of ultrasonic waves to accelerate the degreasing process and improve the degreasing effect.

[0054] Among them, when pickling and activating the electrode sheet, appropriate acid solutions can be selected according to the material of the electrode sheet. For example, for iron-based electrode sheets, dilute hydrochloric acid or dilute sulfuric acid can be used for pickling; for copper-based electrode sheets, dilute nitric acid can be used, etc. Immerse the electrode sheet in the acid solution for a period of time, and the acid solution reacts with the impurities and oxides on the surface of the electrode sheet to generate substances such as salts soluble in water.

[0055] Among them, deionized water can also be used to rinse the electrode sheet for the second time. The rinsing method is similar to the first rinsing, and methods such as soaking, ultrasonic cleaning, or high-pressure water rinsing can be adopted to ensure that the residual acid solution and other impurities on the surface of the electrode sheet are completely removed.

[0056] Among them, when drying the electrode sheet, the electrode sheet can be placed in an oven and dried at a certain temperature. The drying temperature and time are adjusted according to factors such as the material and size of the electrode sheet. Generally, the temperature is about 50 - 100 °C and the drying time is 1 - 2 hours. Natural air drying can also be adopted. Place the electrode sheet in a well-ventilated and dry environment to allow the water to evaporate naturally, but this method takes a longer time. Equipment such as a hair dryer can also be used to blow dry the electrode sheet to quickly remove the surface moisture.

[0057] In some possible embodiments disclosed in the present application, after the reaction ends, the method further includes:

[0058] Detect the microscopic morphology, particle size and phase structure of the electrolysis products.

[0059] In this application, by detecting the microscopic morphology, information such as the particle size, shape, particle size distribution, and agglomeration state of the electrolysis products can be visually observed. By detecting the phase structure, information such as the crystal structure of the electrolysis products, the presence of impurity phases, and the relative content of each phase can be determined, which helps to deeply study the mechanism and process of the electrolysis reaction and provides data support for the improvement and innovation of the process.

[0060] Among them, tools such as electron microscopes can be used to observe and analyze the appearance morphology of the electrolysis products at the microscopic level.

[0061] Specifically, if the particles of the electrolysis products show uniform spherical shapes and a narrow particle size distribution, it indicates that the nucleation and growth processes of the electrolysis reaction are relatively stable and uniform; if the particles of the electrolysis products show agglomeration phenomena, it may affect heat transfer and mass diffusion during the subsequent calcination process, and attention needs to be paid or measures need to be taken for dispersion in the subsequent process.

[0062] Example 1

[0063] A method for preparing germanium dioxide, comprising:

[0064] S1) Prepare a concentrated hydrochloric acid solution of germanium tetrachloride, where the concentration of germanium tetrachloride is 0.76 mol / L, the concentration of concentrated hydrochloric acid is 5.02 mol / L, and the mass fraction is 36%. The temperature during preparation is 20 °C to prevent the hydrolysis reaction of germanium tetrachloride in the mixed solution.

[0065] S2) Inject germanium tetrachloride into the anode chamber and concentrated hydrochloric acid into the cathode chamber to construct an efficient reaction system using an electrolytic cell. The volume of the mixed solution is 25 ml, and the mixed solution is electrolyzed at a constant current density and constant temperature. The electrodes are both platinum electrodes, and the current density is 200 mA / cm 2 , and the reaction duration is 6 hours. Chlorine gas is generated at the anode and hydrogen gas is generated at the cathode, reducing the concentration of hydrochloric acid in the mixed solution.

[0066] S3) When the concentration of hydrochloric acid is reduced to 5.2 mol / L, continue the reaction to cause germanium tetrachloride to react with water to form germanium dioxide precipitate. After the reaction ends, centrifuge to separate the germanium dioxide precipitate, wash it with an ethanol solution, and dry it at 60 °C for 24 hours to obtain germanium dioxide with a purity of 99.99% and a yield of 92.83%. The product purity and yield are relatively high, but the particle size is the smallest.

[0067] Example 2

[0068] A method for preparing germanium dioxide, the steps of which are similar to those of Example 1, except that the current density is 400 mA / cm 2 , germanium dioxide with a purity of 99.99% is obtained, the yield is 95.72%, the product purity and yield are the highest, and the particle size distribution is more uniform.

[0069] The current density is 400 mA / cm 2 The particle size distribution diagram at this time is as follows Figure 3 shown, the product particle size distribution is more uniform and the particle size is smaller.

[0070] Example 3

[0071] A method for preparing germanium dioxide, the steps of which are similar to those of Example 1, except that the reaction duration is 12 hours, and germanium dioxide with a purity of more than 99.99% is obtained, and the yield is 100%.

[0072] Example 4

[0073] A method for preparing germanium dioxide, the steps of which are similar to those of Example 1, except that when preparing the mixed solution, the temperature is 30 °C, and germanium dioxide with a purity of more than 99.99% is obtained, and the yield is 92.61%.

[0074] The above are only the preferred specific embodiments of this application, and are not limited to the above embodiments. Although the present application has been described in detail with general descriptions and specific embodiments above, on the basis of this application, some modifications or improvements can be made, which are obvious to those skilled in the art.

Claims

1. A method for preparing germanium dioxide, characterized in that, Including: Preparing a concentrated hydrochloric acid solution of germanium tetrachloride to prevent hydrolysis of germanium tetrachloride in the mixed solution; Electrolyzing the mixed solution to generate chlorine gas at the anode and hydrogen gas at the cathode, thereby reducing the concentration of hydrochloric acid in the mixed solution; When the concentration of hydrochloric acid is reduced to a threshold value that promotes the hydrolysis reaction of germanium tetrachloride with water, continuously reacting to cause the germanium tetrachloride to react with water to form germanium dioxide precipitate. After the reaction ends, separate the germanium dioxide precipitate.

2. The preparation method of germanium dioxide according to claim 1, characterized in that, The concentration of germanium tetrachloride in the mixed solution is 0.76 mol / L.

3. The preparation method of germanium dioxide according to claim 1, characterized in that, The mass fraction of the concentrated hydrochloric acid is 36 - 38%.

4. The method for preparing germanium dioxide according to claim 1, wherein When preparing the mixed solution, the temperature is 20 - 30 °C.

5. The method for preparing germanium dioxide according to claim 1, wherein Both the anode and the cathode are platinum electrodes.

6. The preparation method of germanium dioxide according to claim 1, wherein Electrolysis is carried out at a constant current density and a constant temperature, and the reaction duration is 1.5 - 12 hours.

7. The method for preparing germanium dioxide according to claim 1, wherein The current density in the electrolysis process is 200 - 400 mA / cm 2 .

8. The method for preparing germanium dioxide according to claim 1, wherein, The threshold value of the concentration of hydrochloric acid is 5.2 mol / L.

9. The method for preparing germanium dioxide according to claim 1, wherein The separation method is centrifugal separation.

10. The method for preparing germanium dioxide according to claim 1, characterized in that, It also includes washing the separated germanium dioxide precipitate with an ethanol solution and drying it at 50 - 60 °C for 24 hours.

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