Process for the recovery of valuable metal elements from tungsten-containing alloys

Abstract

A method for recovering valuable metal elements from a tungsten-containing alloy, comprising a setting step and an electrochemical step. The setting step is to immerse a cathode and a tungsten-containing alloy as an anode into an electrolytic solution, and to make the pH value of the electrolytic solution one of neutral, not greater than 2, or not less than 10. The electrochemical step is to apply a voltage for anodic treatment, so that when the voltage passes through the anode, a power density of not less than 3 W / cm 2 is generated, the metal oxide layer formed on the surface of the anode during anodic treatment is broken through, so that the anode can be continuously oxidized and released from the anode, to obtain at least one of a tungsten-containing ionic compound that can be dissolved in the electrolytic solution, or a tungsten-containing oxide precipitated in the electrolytic solution.

Description

Technical Field

[0001] This invention relates to an electrochemical recovery method, and more particularly to an electrochemical recovery method for tungsten-containing alloys. Background Technology

[0002] Tungsten alloys, with their high density, high hardness, and high melting and boiling points, have become popular materials in machining, military, and aerospace fields. Tungsten carbide, in particular, is widely used in cutting tools, wear-resistant implements, and other mechanical components, and accounts for more than half of the world's tungsten alloy resources. Therefore, the recycling of tungsten carbide and other tungsten alloys has become a key research focus in related fields.

[0003] Currently, common methods for tungsten alloy recycling in the industry include mechanical crushing, pyrometallurgy, hydrometallurgy, and electrochemical methods. Among these, electrochemical methods offer advantages such as high efficiency, high purity, and low solvent consumption. Taking the electrochemical recycling of tungsten carbide as an example, the tungsten carbide to be recycled is placed as the anode in an electrolyte for anodic treatment. This allows cobalt, which acts as a binder in the tungsten carbide, to be released from the anode, thereby obtaining tungsten or tungsten carbide separated from the anode. However, during electrochemical recycling, the anode passivation phenomenon, caused by the formation of oxides on the anode surface, leads to a decrease in recycling efficiency and incomplete separation of cobalt, resulting in the inability to improve the purity of the recycled products (i.e., tungsten or tungsten carbide). Summary of the Invention

[0004] The purpose of this invention is to provide a method for recovering valuable metal elements from tungsten alloys, which can effectively recover and improve the purity of the recovered products.

[0005] The present invention relates to a method for recovering valuable metal elements from tungsten-containing alloys, comprising a setup step and an electrochemical step.

[0006] The setup step involves immersing the cathode and the tungsten-containing alloy serving as the anode into an electrolyte solution, and controlling the pH value of the electrolyte solution to be neutral, not greater than 2, or not less than 10.

[0007] The electrochemical step applies a voltage to perform anodic treatment, and controls the power density of the voltage passing through the anode to be no less than 3 W / cm². 2 This allows the voltage to break down the metal oxide layer formed on the anode surface during the anodic treatment, so that the tungsten alloy can be continuously oxidized and released to obtain a tungsten-containing ionic compound that can be dissolved in the electrolyte or a tungsten-containing oxide that precipitates in the electrolyte.

[0008] Preferably, in the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention, in the setting step, the pH value of the electrolytic solution is neutral or not greater than 2, and in the electrochemical step, the tungsten-containing oxide precipitated in the electrolytic solution can be obtained.

[0009] Preferably, in the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention, in the setting step, the pH value of the electrolytic solution is not less than 10, and the electrochemical step is to obtain the tungsten-containing ionic compound dissolved in the electrolytic solution.

[0010] Preferably, the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention further includes a precipitation step performed after the electrochemical step, wherein the precipitation step involves adding an acidic electrolyte to the electrolytic solution to cause the tungsten-containing ionic compound to react and precipitate as the tungsten-containing oxide.

[0011] Preferably, in the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention, the power density is between 3 W / cm². 2 Up to 35W / cm 2 .

[0012] Preferably, in the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention, the electrolytic solution in the setting step is prepared with hydrochloric acid.

[0013] Preferably, in the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention, in the setting step, the tungsten-containing alloy is selected from tungsten steel, tungsten-lanthanum alloy, or tungsten metal doped with other elements.

[0014] Preferably, in the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention, the tungsten-containing alloy is selected from tungsten steel, and in the electrochemical step, the power density generated when the voltage passes through the anode is between 3 W / cm². 2 Up to 35W / cm 2 The anode has a solubility of not less than 15 mg / min, and the electrochemical step yields hydrated tungsten oxide with a purity of not less than 90%, as well as cobalt reduced from the cathode.

[0015] Preferably, in the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention, the tungsten-containing alloy is selected from tungsten steel, and in the electrochemical step, the power density generated when the voltage passes through the anode is between 3 W / cm². 2 Up to 35W / cm 2Tungstates dissolved in the electrolyte solution and cobalt oxide precipitated in the electrolyte solution can be obtained. The precipitation step involves filtering the cobalt oxide out of the electrolyte solution and then adding an acidic electrolyte to the electrolyte solution to cause the tungsten-containing ion compound to react and form the tungsten-containing oxide.

[0016] Preferably, in the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention, the temperature of the electrolytic solution is controlled between 60°C and 80°C during the electrochemical step.

[0017] The beneficial effect of this invention is that, by controlling the power density of the voltage passing through the tungsten-containing alloy during anodizing to be no less than 3 W / cm², the invention achieves the following: 2 Sufficient energy is available to break down the metal oxide layer formed on the surface of the tungsten alloy, thus preventing the tungsten alloy, which serves as the anode, from being affected by anode passivation, which would lead to a decrease in the decomposition rate and affect the recovery efficiency of valuable metals. Furthermore, by adjusting the pH of the electrolyte solution, the tungsten metal released from the anode can be converted into a tungsten-containing ionic compound soluble in the electrolyte solution, or a tungsten-containing oxide precipitated in the electrolyte solution, allowing for easy recovery through methods such as filtration. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating an embodiment of the method for recovering valuable metal elements from tungsten-containing alloys according to the present invention;

[0019] Figure 2 This is a diagram, for illustrative purposes only. Figure 1 The implementation details of the above embodiments are described. Detailed Implementation

[0020] Before the present invention is described in detail, it should be noted that similar elements are represented by the same numbers in the following description. Furthermore, the relevant technical content, features, and effects of the present invention will be clearly presented in the following detailed description of the embodiments with reference to the accompanying drawings. In addition, it should be noted that the drawings of the present invention are only for illustrating the structural and / or positional relationships between elements and are not related to the actual dimensions of each element.

[0021] See Figure 1 and Figure 2 An embodiment of the method for recovering valuable metal elements from tungsten alloys of the present invention includes a setup step 21 and an electrochemical step 22.

[0022] In the setting step 21, the cathode 3 and the tungsten-containing alloy serving as the anode 4 are immersed in the electrolyte solution 5, and the pH value of the electrolyte solution 5 is controlled to be neutral, not greater than 2, or not less than 10.

[0023] The cathode 3 can be selected from pure tungsten or an inert metal.

[0024] The tungsten-containing alloy can be selected from tungsten steel (i.e., tungsten carbide doped with cobalt), tungsten-lanthanum alloy, or tungsten metal doped with other trace impurities or elements, etc., from tungsten-containing waste recycled components. Furthermore, the tungsten-containing alloy can be, for example, from... Figure 2 The diagram shows a metal rod that is directly connected to a power supply, or a tungsten-containing waste recycling element of different shapes can be placed in an electrolytic basket (not shown) connected to the power supply. As long as the voltage applied by the power supply can be passed through the tungsten-containing alloy as the anode 4 for anodizing, the structural form is not limited to the examples mentioned above.

[0025] The electrolyte solution 5 is prepared by dissolving one of an acidic electrolyte, a neutral electrolyte, or an alkaline electrolyte in a solvent (e.g., deionized water). The acidic electrolyte is selected from hydrochloric acid, sulfuric acid, or other inorganic acids; the alkaline electrolyte is selected from sodium carbonate or other inorganic bases; and the neutral electrolyte is selected from sodium chloride or other supporting electrolytes. Preferably, the electrolyte solution 5 is prepared using hydrochloric acid as the acidic electrolyte.

[0026] The electrochemical step 22 involves applying voltage to perform anodic treatment while maintaining the temperature of the electrolyte solution 5 at a non-boiling level. Preferably, the temperature of the electrolyte solution 5 is controlled between 60°C and 80°C because when the temperature is above 80°C, the solvent in the electrolyte solution 5 is prone to evaporation or boiling, resulting in solvent loss and a change in concentration; when the temperature is below 60°C, the reaction rate of the electrochemical reaction will be too slow, and the introduction of a high-power voltage will generate heat, making it difficult to maintain a stable temperature.

[0027] Because a metal oxide layer coating the anode 4 (containing a tungsten alloy) is formed on the surface of the anode 4 due to an electrochemical reaction during the anode treatment process, and this metal oxide layer affects the progress of the electrochemical reaction, the electrochemical step 22 of the present invention specifically controls the voltage so that the power density when the voltage passes through the anode 4 is not less than 3 W / cm². 2 This allows the voltage to break down the metal oxide layer, enabling the tungsten-containing alloy coated by the metal oxide layer to be continuously oxidized and released from the anode 4. Depending on the characteristics of the electrolyte 5, tungsten-containing ionic compounds soluble in the electrolyte 5 or tungsten-containing oxides precipitated in the electrolyte 5 can be continuously obtained. Furthermore, as the power density through the anode 4 gradually increases, the electrochemical reaction rate increases accordingly, and the purity of the obtained tungsten-containing oxide is also higher. Preferably, the power density is between 3 W / cm². 2 Up to 35W / cm2 For example, the power density of the tungsten-containing alloy is less than 3 W / cm³. 2 The voltage energy is insufficient to break down the metal oxide layer on the surface of the tungsten alloy, causing the contact area between the tungsten alloy inside the anode 4 and the electrolyte solution 5 to decrease with increasing process time. This results in a gradual decrease in the dissolution rate of the tungsten alloy during the electrochemical reaction. When the power density is increased to 35 W / cm², 2 The voltage it provides is close to the upper limit of voltage that can be provided by a typical commercially available voltage supply.

[0028] In other embodiments, the power density may be 3.5 W / cm². 2 7W / cm 2 13W / cm 2 27W / cm 2 28W / cm 2 Or 34W / cm 2 Or between 3.5 and 34.5 W / cm 2 Or between 27 and 34.5 W / cm 2 Or between 27.6 and 34.5 W / cm 2 .

[0029] Specifically, during the anodic treatment of the electrochemical step 22, the power density generated when the voltage passes through the anode 4 is not less than 3 W / cm². 2 Sufficient energy is available to break through the metal oxide layer covering the surface of the anode 4, exposing the internal tungsten alloy for continuous oxidation. Furthermore, since the oxidation state of tungsten changes in solutions with different pH values, the form of the recovered product obtained after the electrochemical step 22 can be controlled by adjusting the pH of the electrolyte solution 5. Specifically, when the electrolyte solution 5 is a neutral solution or an acidic solution with a pH value not greater than 2, the tungsten alloy after anodizing will form tungsten oxide precipitated in the electrolyte solution 5; when the electrolyte solution 5 is an alkaline solution with a pH value not less than 10, the tungsten alloy after anodizing will form a tungsten ionic compound soluble in the electrolyte solution 5.

[0030] In some embodiments, when the pH value of the electrolyte solution 5 is not less than 10, the method for recovering valuable metal elements of tungsten alloys of the present invention may further include a precipitation step 23 performed after the electrochemical step 22. The precipitation step 23 involves adding an acidic electrolyte to the electrolyte solution 5, so that the tungsten-containing ionic compounds that were originally dissolved in the alkaline electrolyte solution 5 react under acidic conditions to form tungsten oxide precipitates.

[0031] The tungsten alloy used as the anode 4 in the above embodiment is selected from tungsten steel and tungsten-lanthanum alloy. The recovery method of this embodiment using an electrolyte solution 5 with different pH values ​​is explained through the following specific examples 1 to 8 and comparative examples 1 and 2. The results, such as the purity of the recovered product and the dissolution rate of the anode 4, are summarized in Table 1. The product purity was measured by energy-dispersive X-ray spectroscopy (EDS), and the dissolution rate of the anode 4 was obtained by dividing the weight difference of the anode 4 before and after performing the electrochemical step 22 by the process time.

[0032] Specific example 1

[0033] An electrolytic solution 5 with a concentration of 1M and a pH of approximately 0 is prepared by dissolving hydrochloric acid (HCl) in water as the acidic electrolyte. A rod-shaped tungsten carbide (anode 4) and a tungsten metal rod (cathode 3) are immersed in the electrolytic solution 5. Next, a voltage is applied for anodic treatment, and the power density generated when the voltage is controlled to pass through the tungsten carbide is approximately 3.5 W / cm³. 2 The metal oxide layer formed on the surface of the anode 4 can be broken down and dispersed into the electrolyte solution 5, forming hydrated tungsten oxide (WO3·nH2O) precipitated in the electrolyte solution 5. The hydrated tungsten oxide can be obtained by filtration, and the purity of the hydrated tungsten oxide can be as high as 98.35%. The process time of the anode treatment (i.e., the electrochemical step 22) is 10 minutes, and the dissolution rate of the anode 4 in Example 1 during the process time is 26.7 mg / min.

[0034] Furthermore, during the anode treatment, the cobalt element contained in the tungsten steel can be released from the tungsten steel to form a cobalt-containing complex dissolved in the electrolyte solution 5, thereby making the electrolyte solution 5 contain cobalt ions, and at least a portion of the cobalt element is reduced from the cathode 3, and the purity of the cobalt element produced by the reduction at the cathode 3 can reach 93.6%.

[0035] Specific examples 2 to 4

[0036] Examples 2 to 4 are similar to Example 1, except that in Examples 2 to 4, the power density generated by the tungsten steel is controlled to be 13.8 W / cm² during the anodizing process. 2 27.6W / cm 2 and 34.5W / cm 2The metal oxide layer is broken down and dispersed into the electrolyte solution 5, resulting in hydrated tungsten oxide precipitated in the electrolyte solution 5 with purities of 99.32%, 99.99%, and 99.99%, respectively; cobalt-containing ion complex dissolved in the electrolyte solution 5; and cobalt element reduced from the cathode 3. In specific examples 2 to 4, the dissolution rates of the anode 4 during the process time are 57.8 mg / min, 110.9 mg / min, and 147.5 mg / min, respectively.

[0037] Specific example 5

[0038] Specific Example 5 is similar to Specific Example 1, except that the anode 4 in Specific Example 5 is selected from a tungsten-lanthanum alloy, and during the anode treatment, the power density through the tungsten-lanthanum alloy is controlled to be 34.5 W / cm². 2 The metal oxide layer is broken down and dispersed into the electrolyte solution 5, resulting in hydrated tungsten oxide precipitated in the electrolyte solution 5 with a purity of up to 99.99%, lanthanum-containing complex dissolved in the electrolyte solution 5, and lanthanum element reduced from the cathode 3. In this specific example 5, the anode 4 has a solubility rate of 35.2 mg / min during the process time.

[0039] Specific example 6

[0040] Specific Example 6 is similar to Specific Example 1, except that in Specific Example 6, sulfuric acid (H2SO4) is dissolved in water as the acidic electrolyte to prepare an electrolytic solution 5 with a concentration of 1M and a pH value of approximately 0. Then, a voltage is applied for anodic treatment, and the power density passing through the tungsten steel is controlled at 3.5 W / cm². 2 The metal oxide layer is broken down and dispersed into the electrolyte solution 5, resulting in hydrated tungsten oxide with a purity of 99.36% precipitated in the electrolyte solution 5, a cobalt-containing complex dissolved in the electrolyte solution 5, and cobalt element reduced from the cathode 3. In this specific example 6, the anode 4 has a dissolution rate of 16 mg / min during the process time.

[0041] Specific example 7

[0042] Specific Example 7 is similar to Specific Example 1, except that in Specific Example 7, sodium chloride (NaCl) is dissolved in water as a neutral electrolyte to prepare an electrolytic solution 5 with a concentration of 1M and a pH value of approximately 7. Then, a voltage is applied for anodic treatment, controlling the power density through the tungsten steel to be 6.9 W / cm². 2The metal oxide layer is broken down and dispersed into the electrolyte solution 5, resulting in hydrated tungsten oxide precipitated in the electrolyte solution 5 with a purity of 94.32%, a cobalt-containing complex dissolved in the electrolyte solution 5, and cobalt element reduced from the cathode 3. In this specific example 7, the anode 4 has a solubility rate of 22.6 mg / min during the process time.

[0043] Specific example 8

[0044] Specific Example 8 is similar to Specific Example 1, except that in Specific Example 8, sodium carbonate (Na2CO3) is dissolved in water as an alkaline electrolyte to prepare an electrolytic solution 5 with a concentration of 1M and a pH value of approximately 12. Then, a voltage is applied for anodic treatment, and the power density passing through the tungsten steel is controlled to be 6.9 W / cm². 2 This disperses the metal oxide layer into the electrolyte solution 5, forming tungstate ions (WO4) dissolved in the electrolyte solution 5. 2- The cobalt released from the anode will form cobalt oxide (CoO) and / or cobalt hydroxy oxide (Co(OH)2) precipitated in the electrolyte solution 5, and the purity of the cobalt oxide is 93.06%.

[0045] Subsequently, in Specific Example 8, the precipitation step 23 can be performed again, filtering the cobalt oxide from the electrolyte solution 5, and then adding an acidic electrolyte (e.g., hydrochloric acid or sulfuric acid) to the electrolyte solution 5 after the cobalt oxide has been filtered out, so that the tungstate ions react in an acidic environment to form hydrated tungsten oxide (i.e., tungstic acid) precipitated in the electrolyte solution 5. In Specific Example 8, the dissolution rate of the anode 4 during the process time is 13.8 mg / min.

[0046] Comparative Example 1

[0047] Comparative Example 1 is similar to Specific Example 1, except that no voltage was applied to Comparative Example 1 (power density was 0 W / cm²). 2 The process involved immersing the tungsten carbide, serving as the anode 4, in the electrolyte solution 5 for only 10 minutes. No precipitate was formed during the entire process, and the dissolution rate of the anode 4 in Comparative Example 1 during the process was 0.2 mg / min.

[0048] Comparative Example 2

[0049] Comparative Example 2 is similar to Specific Example 1, except that in Comparative Example 2, the power density generated by the tungsten steel is controlled at 1.7 W / cm² when applying voltage for anodizing. 2No precipitate was produced in Comparative Example 2 during the entire process time (10 minutes), and the dissolution rate of the anode 4 in Comparative Example 2 during the process time was 4.2 mg / min.

[0050] Table 1

[0051]

[0052]

[0053] It should be noted that the cobalt-containing complexes generated during the anodic treatment in Examples 1 to 4, and 6 and 7 can also be reacted by adding an alkaline electrolyte or a precipitant (e.g., oxalic acid) to the electrolyte solution 5 after filtering out the precipitated hydrated tungsten oxide, causing the cobalt-containing complexes to precipitate in the electrolyte solution 5. Alternatively, direct current can be passed through the electrolyte solution, and cobalt metal can be formed by electroplating and precipitated from the electrolyte solution 5.

[0054] As shown in Table 1, the power density is no greater than 3 W / cm² compared to when no voltage is applied (Comparative Example 1) or when the anode treatment is performed. 2 In the case of (Comparative Example 2), the dissolution rate of anode 4 was less than 5 mg / min, resulting in poor metal recovery. However, the present invention controls the voltage to ensure that the power density generated when passing through anode 4 is not less than 3 W / cm². 2 Under these conditions, regardless of whether the electrolyte solution 5 is acidic, alkaline, or neutral, the dissolution rate of the anode 4 can reach over 13 mg / min, and as the power density passing through the anode 4 increases to nearly 35 W / cm², the dissolution rate can be achieved. 2 (For example, in Specific Example 5), the dissolution rate of the anode 4 can reach as high as 147.5 mg / min or more, without being affected by the anode passivation in conventional electrochemical tungsten alloy recovery, which leads to a decrease in dissolution rate (i.e., electrochemical passivation). Furthermore, by adjusting the pH of the electrolyte solution 5, the oxidation state of the tungsten and other valuable metals (cobalt, lanthanum) released from the tungsten alloy can be changed, causing them to dissolve or precipitate in the electrolyte solution 5. Therefore, the recovered tungsten alloy product can be easily separated and obtained by means such as filtration. As shown in Table 1, the purity of the hydrated tungsten oxide (i.e., the tungsten oxide) obtained by the recovery method of the present invention is not less than 90%, and the power density increases by 27 W / cm² when passing through the anode 4. 2Under the above conditions, and with the electrolyte solution 5 being acidic (hydrochloric acid) (for example, in Examples 3 to 4), the dissolution rate of the anode 4 can be greater than 110 mg / min, indicating that the electrochemical reaction rate can be faster, and the purity of the hydrated tungsten oxide obtained can reach 4N (99.99%), thus enabling more effective recovery of the valuable metals of the tungsten alloy.

[0055] In summary, the method for recovering valuable metal elements from tungsten-containing alloys of the present invention controls the power density generated by the voltage through the anode 4 (containing tungsten alloy) during anodic treatment to be no less than 3 W / cm². 2 This allows the metal oxide layer formed on the surface of the tungsten alloy to be broken down by the voltage and peeled off from the anode 4, avoiding the tungsten alloy 4, which serves as the anode, from being affected by anode passivation, thus preventing a decrease in the decomposition rate. In addition, by adjusting the pH value of the electrolyte solution 5, the oxidation state of tungsten can be changed, so that the metal oxide layer released from the anode 4 becomes a tungsten-containing ionic compound (tungstate compound) soluble in the electrolyte solution 5, or a tungsten-containing oxide (hydrated tungsten oxide, various hydrates of tungsten trioxide) precipitated in the electrolyte solution 5, which can be easily filtered out, thus effectively achieving the purpose of the present invention.

Claims

1. A method for recovering valuable metal elements from tungsten-containing alloys, characterized in that: Include: The setup steps involve immersing the cathode and the tungsten-containing alloy serving as the anode in an electrolyte solution, and controlling the pH value of the electrolyte solution to be neutral, not greater than 2, or not less than 10. and In the electrochemical step, a voltage is applied to perform anodic treatment, and the power density is controlled to be not less than 3 W / cm² when the voltage passes through the anode. 2 This allows the voltage to break down the metal oxide layer formed on the anode surface during the anodic treatment, so that the tungsten alloy can be continuously oxidized and released to obtain a tungsten-containing ionic compound that can be dissolved in the electrolyte or a tungsten-containing oxide that precipitates in the electrolyte.

2. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 1, characterized in that: In the setup step, the pH value of the electrolyte solution is neutral or not greater than 2, and the tungsten oxide precipitated in the electrolyte solution can be obtained in the electrochemical step.

3. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 1, characterized in that: In the setup step, the pH value of the electrolyte solution is not less than 10, and the electrochemical step is to obtain the tungsten-containing ion compound dissolved in the electrolyte solution.

4. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 3, characterized in that: It also includes a precipitation step performed after the electrochemical step, wherein the precipitation step involves adding an acidic electrolyte to the electrolyte solution to cause the tungsten-containing ion compound to react and precipitate as the tungsten-containing oxide.

5. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 1, characterized in that: The power density is between 3W / cm² 2 Up to 35W / cm 2 .

6. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 2, characterized in that: In the setup step, the electrolyte solution is prepared with hydrochloric acid.

7. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 1, characterized in that: In the setting step, the tungsten-containing alloy is selected from tungsten steel and tungsten-lanthanum alloy.

8. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 2, characterized in that: The tungsten-containing alloy is selected from tungsten steel, and in the electrochemical step, the power density generated when the voltage passes through the anode is between 3 W / cm². 2 Up to 35W / cm 2 The anode has a solubility of not less than 15 mg / min, and the electrochemical step yields hydrated tungsten oxide with a purity of not less than 90%, as well as cobalt reduced from the cathode.

9. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 4, characterized in that: The tungsten-containing alloy is selected from tungsten steel, and in the electrochemical step, the power density generated when the voltage passes through the anode is between 3 W / cm². 2 Up to 35W / cm 2 Tungstates dissolved in the electrolyte solution and cobalt oxide precipitated in the electrolyte solution can be obtained. The precipitation step involves filtering the cobalt oxide out of the electrolyte solution and then adding an acidic electrolyte to the electrolyte solution to cause the tungsten-containing ion compound to react and form the tungsten-containing oxide.

10. The method for recovering valuable metal elements from tungsten-containing alloys according to claim 1, characterized in that: In the electrochemical step, the temperature of the electrolyte solution is controlled between 60°C and 80°C.

Images