Copper-tungsten alloy waste recovery method based on in-situ hydrogen production principle
By optimizing the recycling process of tungsten-copper alloy waste through an oxidation-reduction process based on the principle of in-situ hydrogen production and an internal hydrogen circulation system, the problems of high energy consumption, low resource recycling efficiency and environmental pollution have been solved, achieving efficient and clean metal separation and recycling.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CENT SOUTH UNIV
- Filing Date
- 2026-03-24
- Publication Date
- 2026-05-08
AI Technical Summary
Existing methods for recycling tungsten-copper alloy waste suffer from problems such as high energy consumption, low resource recovery efficiency, complex processes, serious environmental pollution, and poor equipment adaptability, making it difficult to achieve efficient and clean metal separation and recycling.
The process employs an oxidation-reduction technique based on the principle of in-situ hydrogen production, combined with a mixture separation and internal hydrogen circulation system. Through steps such as primary crushing, oxidation, primary reduction, separation, secondary reduction, screening, secondary crushing, airflow pulverization, and acid washing to remove impurities, the equipment integration is optimized to improve energy utilization efficiency and product purity.
It achieves efficient and clean recycling of tungsten-copper alloy waste, with a tungsten recovery rate of 99.2% and a copper recovery rate of 99.5%. The product has high purity, meets the requirements for high-value utilization, and has no environmental pollution, which is in line with the concept of green and low-carbon development.
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Figure CN121992205A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of clean metallurgy and resource recycling technology for non-ferrous metal waste, specifically to a method for recycling and treating clean, low-carbon tungsten-copper alloy waste based on the principle of in-situ hydrogen production. Background Technology
[0002] Tungsten-copper alloy is a pseudo-alloy composite material composed of high-melting-point, high-hardness tungsten (melting point 3422℃) and highly conductive and thermally conductive copper (melting point 1085℃). It combines the arc erosion resistance and weldability of tungsten with the excellent electrical and thermal conductivity of copper. This material is commonly used in high-voltage electrical contacts, EDM electrodes, electronic packaging, and heat sink components. The production and use processes generate a large amount of waste such as turning chips and fragments; therefore, efficient recycling of this material is crucial for conserving strategic resources and reducing production costs.
[0003] Existing technologies for recycling tungsten-copper alloy waste mainly include mechanical separation, vacuum distillation, and hydrometallurgy. Mechanical separation is inefficient and struggles to achieve complete dissociation of tungsten and copper. While vacuum distillation can directly separate the metal elements, it requires prolonged operation at high temperatures of 800–1000°C and high vacuum of 1–10 Pa, resulting in complex equipment, extremely high energy consumption, and stringent requirements for raw material purity. Hydrometallurgy typically involves leaching with strong acids (such as nitric acid), resulting in lengthy processes and generating large amounts of acidic wastewater containing heavy metals and toxic gases (such as nitrogen oxides), posing significant environmental pollution risks and incurring high costs for subsequent wastewater treatment. These traditional methods generally suffer from high energy consumption, complex processes, severe secondary pollution, or difficulty in achieving both high metal recovery rates and purity, contradicting the current green, low-carbon, and circular economy development philosophy.
[0004] Clean metallurgical technologies, exemplified by hydrogen metallurgy, utilize hydrogen (H2) as a reducing agent to react with metal oxides under heating conditions, producing elemental metals and water (H2O). Theoretically, this process does not generate carbon dioxide (CO2) or other sulfur- and nitrogen-containing pollutants, making it a key pathway to achieving low-carbon and zero-pollution metal smelting and recycling processes. Compared to traditional recycling methods relying on carbothermic reduction or highly polluting hydrometallurgical processes, hydrogen reduction technology provides a new solution for the efficient and clean separation and extraction of non-ferrous metals such as tungsten and copper from complex waste materials.
[0005] Although metallurgical technology and equipment on the market are constantly improving, some common shortcomings still exist, and some obvious problems remain unresolved. These mainly include the following aspects:
[0006] 1. High energy consumption and low energy utilization: Oxidation, reduction and volatilization separation processes all need to be carried out at high temperatures (400℃~1100℃). Traditional equipment thermal integration design is insufficient, a large amount of reaction waste heat is not effectively recovered and utilized, and the overall thermal efficiency of the system is low.
[0007] 2. Low resource recovery efficiency and difficulty in ensuring product quality: The narrow process control window easily leads to the volatilization loss or incomplete dissociation of valuable metals (such as tungsten), resulting in a low overall recovery rate. At the same time, intermediate products or impurities are difficult to remove, resulting in insufficient purity of the final recovered metal powder, which affects its high-value utilization.
[0008] 3. Poor process coupling and discontinuous process: Most studies focus on the optimization of single reactions (such as oxidation or reduction), lacking the design of continuous and automated systems that efficiently integrate multiple steps such as oxidation, selective reduction, and volatilization separation, resulting in frequent material transfer, large heat loss, and low production efficiency.
[0009] 4. Significant environmental pollution and safety risks: High-temperature processes may produce harmful volatile substances, while wet processes use large amounts of acids and alkalis, resulting in wastewater and waste residue containing heavy metals, posing serious secondary pollution risks and high end-of-pipe treatment costs.
[0010] 5. Poor equipment adaptability and high maintenance and operating costs: Traditional equipment is mostly fixed and specialized in design, making it difficult to flexibly adapt to waste materials of different sources and characteristics. The equipment operates under harsh conditions such as high temperature, corrosion, or high vacuum for a long time, resulting in rapid component wear and frequent maintenance, leading to poor production continuity and high overall operating costs. Summary of the Invention
[0011] To address the technical deficiencies in the background technology, this invention proposes a method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production. This method is based on an optimized oxidation-reduction process and integrates a high-efficiency resource recovery device with a mixture separation and hydrogen internal circulation system. The aim is to solve common problems associated with traditional recycling methods for handling such refractory and highly stable waste, including environmental pollution, high energy consumption, complex processes, high costs for processing waste from dispersed sources, and safety risks associated with alternating high-temperature, oxidizing, and reducing atmospheres. Simultaneously, it focuses on improving the overall energy utilization efficiency and resource recycling level of the system. The specific technical solution is shown below:
[0012] A method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production includes the following steps:
[0013] S1 primary crushing: Prepare tungsten-copper alloy waste, crush the waste to obtain tungsten-copper alloy powder;
[0014] S2 oxidation: Tungsten copper alloy powder is oxidized to obtain a mixed powder of copper oxide and tungsten trioxide;
[0015] S3 primary reduction: The copper oxide-tungsten trioxide mixed powder is reduced to obtain copper-tungsten trioxide mixed powder;
[0016] S4 separation: The copper-tungsten trioxide mixed powder is separated to obtain tungsten trioxide powder and copper powder;
[0017] S5 Secondary Reduction: Tungsten trioxide powder is reduced to obtain tungsten powder;
[0018] S6 Screening: Use a 100~500 mesh standard sieve to sieve to obtain tungsten powder and copper powder that can pass through the 100~500 mesh standard sieve;
[0019] S7 triple reduction: Unsieved tungsten powder and copper powder are reduced again;
[0020] S8 Secondary Crushing: The tungsten powder and copper powder that have passed through step S7 are crushed to obtain tungsten powder and copper powder;
[0021] S9 Airflow pulverization: The tungsten powder and copper powder obtained in steps S6 and S8 are loaded into an airflow mill for high-pressure airflow pulverization to obtain fine tungsten powder and copper powder with uniform particle size.
[0022] S10 acid washing and impurity removal: Fine tungsten powder and copper powder are acid washed and dried to obtain tungsten powder and copper powder that can pass through a 200~500 mesh standard sieve.
[0023] Specifically, in step S2, tungsten-copper alloy powder is placed in an oxidation reaction vessel. First, oxygen at 0.5 MPa is introduced into the oxidation reaction vessel to increase the oxidation rate of the tungsten-copper alloy powder by increasing the pressure. The mixture is kept at 750°C for 1.8 hours. Then, the oxygen pressure is reduced to 0.25 MPa, and the mixture is kept at 750°C for 0.5 hours. After cooling, a copper oxide-tungsten trioxide mixed powder is obtained. It should be noted that if the temperature exceeds 800°C, tungsten trioxide will evaporate, resulting in product loss.
[0024] Specifically, in step S3, the copper oxide-tungsten trioxide mixed powder is placed in a reduction reactor, nitrogen gas at 0.25 MPa is introduced into the reduction reactor, and then hydrogen gas at 0.25 MPa is introduced into the reduction reactor. The mixture is kept at 450°C for 1 to 1.5 hours and then cooled to obtain copper-tungsten trioxide mixed powder.
[0025] Specifically, in step S4, the copper-tungsten trioxide mixed powder is placed in a reduction reactor, and nitrogen gas at 0.25 MPa is introduced into the reduction reactor. The mixture is heated to 1000°C and held at that temperature for 0.5 to 1 hour until the tungsten trioxide has completely volatilized, leaving copper powder in the reactor. The condensation method uses a multi-stage cooling system to guide the high-temperature flue gas containing tungsten trioxide to a condensation chamber with progressively decreasing temperatures. The first-stage condensation zone is maintained at 650°C, allowing some of the vapor to initially crystallize and precipitate. Subsequently, the gas enters the second and third-stage condensers, where the temperature is further reduced to 400°C and below, allowing the remaining vapor to continue to condense into solid particles. Finally, fine and uniform tungsten trioxide powder can be obtained in the low-temperature section (150°C).
[0026] Specifically, in step S5, the cooled and collected tungsten trioxide powder is placed in a reduction reactor, nitrogen gas at 0.25 MPa is introduced into the reduction reactor, and then hydrogen gas at 0.25 MPa is introduced into the reduction reactor. The mixture is kept at 720°C for 1.5 to 2 hours, then cooled to obtain tungsten powder.
[0027] Specifically, in step S7, unsieved tungsten powder and copper powder are placed in a reduction reactor one after the other. Nitrogen gas at 0.25 MPa is introduced into the reduction reactor, followed by hydrogen gas at 0.25 MPa. The reactor is kept at 720°C and 450°C for 2 hours respectively, and then cooled.
[0028] Specifically, in steps S1 and S8, a ball mill is used for crushing.
[0029] Specifically, in step S9, inert gas is used as a high-pressure gas flow, with the gas pressure controlled at 5~7 kPa, to make the copper powder and tungsten powder particles finer, thereby improving the purity of the tungsten powder and copper powder.
[0030] Specifically, in step S10, fine tungsten powder and copper powder are soaked in a 10-18% hydrochloric acid solution for 8-10 hours, then rinsed with clean water and dried.
[0031] The beneficial effects of this invention are as follows:
[0032] 1. The preparation method of this application first crushes and oxidizes the tungsten-copper alloy waste, and then first hydrogenates the copper, which can solve the problem that the intermediate product copper tungstate cannot be separated in the subsequent process, thereby making the separation of copper and tungsten more thorough.
[0033] 2. By first heating to distill tungsten trioxide, then cooling and separating the tungsten trioxide through a multi-stage condensation chamber, and finally reducing the tungsten trioxide separately, the purity of the product can be improved, the cost of directly separating copper powder and tungsten powder can be reduced, and the waste heat of the reduction reactor can be utilized to reduce energy consumption.
[0034] 3. First, use a 100-500 mesh standard sieve to sieve the copper powder and tungsten powder, and then perform secondary reduction and secondary crushing on the unsieved copper powder and tungsten powder. This can improve the crushing degree and purity of the copper powder and tungsten powder, thereby reducing the oxygen content.
[0035] 4. In the process of air jet milling, inert gas is used as high-pressure airflow. Copper powder and tungsten powder are successively loaded into the air jet mill for high-pressure air jet milling to obtain fine powder with uniform particle size. By combining ordinary crushing with high-pressure air jet milling, finer copper powder and tungsten powder with better particle size uniformity can be obtained. Attached Figure Description
[0036] Figure 1 This is a schematic diagram of the reduction reactor structure;
[0037] Figure 2 This is a schematic diagram of a magnetic field generator.
[0038] Figure 3 This is a schematic diagram of a ball mill structure;
[0039] Figure 4 This is a schematic diagram of the structure of a Type 100 air jet mill - ultrafine powder pulverizer - laboratory micro air jet mill - pulverizer;
[0040] Figure 5 This is a schematic diagram of the pickling system structure;
[0041] Figure 6 This is a schematic diagram of the oxidation reaction vessel.
[0042] Figure 7 This is a schematic diagram of a multi-stage cooling system.
[0043] Figure 8 This is a performance analysis diagram of copper oxide and copper;
[0044] Figure 9 This is a performance analysis diagram of tungsten trioxide and tungsten. Detailed Implementation
[0045] The embodiments of the present invention will be described below with reference to relevant examples. The embodiments of the present invention are not limited to the following examples, and the present invention relates to relevant necessary components in this technical field, which should be regarded as well-known technology in this technical field and can be known and mastered by those skilled in this technical field.
[0046] Example 1: Prepare tungsten-copper alloy turning waste material (70wt% tungsten content, 30wt% copper content) generated from high-voltage electrical contacts, and load the tungsten-copper alloy waste material into a ball mill. Figure 3 The tungsten-copper alloy powder was obtained by crushing it in an oxidation reactor for 2 hours. Figure 6In a reduction reactor, oxygen at 0.5 MPa is first introduced, and the mixture is kept at 750°C for 1.8 hours. Then, the oxygen pressure is reduced to 0.25 MPa, and the mixture is kept at 750°C for another 0.5 hours. After cooling, a copper oxide-tungsten trioxide mixed powder is obtained. The temperature is controlled to not exceed 800°C throughout the process. The copper oxide-tungsten trioxide mixed powder is then placed in a reduction reactor. Figure 1 In a reduction reactor, nitrogen gas at 0.25 MPa is first introduced, followed by hydrogen gas at 0.25 MPa. The mixture is kept at 450 °C for 1.2 h, then cooled to obtain a copper-tungsten trioxide mixed powder. The copper-tungsten trioxide mixed powder is then kept in the reduction reactor. Figure 1 Nitrogen gas at 0.25 MPa is introduced into the chamber, and the temperature is raised to 1000℃ and held for 0.8 hours until the tungsten trioxide has completely volatilized. The high-temperature flue gas containing tungsten trioxide is then guided to a multi-stage cooling system. Figure 7 After being condensed at 650℃, 400℃, and 150℃ in stages, tungsten trioxide powder was collected in the low-temperature section at 150℃ and then reduced in the reactor ( Figure 1 Copper powder is retained inside; the cooled and collected tungsten trioxide powder is placed in a reduction reactor. Figure 1 In the analysis of the properties of tungsten trioxide powder, such as... Figure 9 As shown, nitrogen gas at 0.25 MPa was introduced, followed by hydrogen gas at 0.25 MPa. The mixture was kept at 720°C for 1.8 hours and then cooled to obtain tungsten powder. The copper powder and tungsten powder were then sieved through a 300-mesh standard sieve. The tungsten powder and copper powder that could pass through the 300-mesh standard sieve were collected. The unsieved tungsten powder and copper powder were then placed in a reduction reactor. Figure 1 In each process, nitrogen gas at 0.25 MPa is first introduced, followed by hydrogen gas at 0.25 MPa. Tungsten powder is kept at 720℃ for 2 hours, and copper powder is kept at 450℃ for 2 hours. After cooling, the powder is removed and reloaded into the ball mill. Figure 3 The tungsten powder and copper powder were crushed in an air jet mill for 1.5 hours to obtain refined tungsten powder and copper powder; the tungsten powder and copper powder obtained by sieving and the tungsten powder and copper powder obtained by secondary crushing were respectively loaded into an air jet mill. Figure 4 In the process, inert gas is used as the high-pressure airflow, and the pressure is controlled at 6 kPa for high-pressure airflow pulverization to obtain fine tungsten and copper powder with uniform particle size. Finally, the fine tungsten and copper powder are placed in an acid washing system. Figure 5 The tungsten and copper powders were soaked in a 15% hydrochloric acid solution for 9 hours, rinsed with water until neutral, and then dried to obtain tungsten and copper powders that could pass through a 300-mesh standard sieve. Testing showed a tungsten recovery rate of 99.2% and a copper recovery rate of 99.5%. The oxygen content of both tungsten and copper powders was less than 0.05 wt%. Performance analyses of the copper and tungsten powders are as follows: Figure 8 and Figure 9 As shown.
[0047] Comparative Example 1: Prepare the same tungsten-copper alloy turning waste as in Example 1, and load the tungsten-copper alloy waste into a ball mill ( Figure 3 Tungsten-copper alloy powder was obtained by crushing in a reactor for 2 hours, and then subjected to oxidation reaction in a separate reactor. Figure 6Oxidation and reduction reactors ( Figure 1 Primary reduction, reduction reactor ( Figure 1 ) and multi-stage cooling system ( Figure 7 Separation and reduction reactor ( Figure 1 After secondary reduction, the powder is sieved through a 300-mesh standard sieve, and the sieved powder and unsieved coarse powder are directly mixed and loaded into an air jet mill. Figure 4 Inert gas is used as the high-pressure airflow at a pressure of 6 kPa for high-pressure airflow pulverization, and then the fine powder particles are placed in an acid washing system. Figure 5 The tungsten powder was soaked in 15% hydrochloric acid solution for 9 hours, rinsed with water until neutral, and then dried. After testing, the tungsten recovery rate was 95.1% and the copper recovery rate was 96.3%. The oxygen content of both tungsten powder and copper powder was higher than 0.12 wt%, and the particle size uniformity of the powder was poor.
[0048] Comparative Example 2: Prepare the same tungsten-copper alloy turning waste as in Example 1, and load the tungsten-copper alloy waste into a ball mill ( Figure 3 Tungsten-copper alloy powder was obtained by crushing in a reactor for 2 hours, and then subjected to oxidation reaction in a separate reactor. Figure 6 Oxidation and reduction reactors ( Figure 1 Primary reduction, reduction reactor ( Figure 1 ) and multi-stage cooling system ( Figure 7 Separation and reduction reactor ( Figure 1 Secondary reduction, screening with a 300-mesh standard sieve, reduction reactor ( Figure 1 ) Three-stage reduction, ball mill ( Figure 3 After secondary crushing, the crushed powder is directly placed in the pickling system. Figure 5 The sample was soaked in a 15% hydrochloric acid solution for 9 hours, rinsed with water until neutral, and then dried to obtain tungsten powder and copper powder. The tungsten recovery rate was 98.5%, the copper recovery rate was 98.8%, the oxygen content of the powder was about 0.07 wt%, the particle size D50 was 3-5 μm larger than that of Example 1, and the particle size uniformity was poor.
[0049] Comparative Example 3: The same tungsten-copper alloy turning waste as in Example 1 was treated using a traditional hydrometallurgical process. The tungsten-copper alloy waste was crushed and leached with concentrated nitric acid, heated to 80°C and held for 4 hours, and filtered to obtain a copper salt solution and tungsten slag. The copper salt solution was replaced and electrolyzed to obtain copper powder, and the tungsten slag was dissolved in alkali, precipitated in acid, and reduced with hydrogen to obtain tungsten powder. Finally, the obtained copper powder and tungsten powder were acid washed and dried. The tungsten recovery rate was 94.3% and the copper recovery rate was 95.6%. The powder purity was lower than that of Example 1, and a large amount of nitrogen oxide-containing waste gas and heavy metal acidic wastewater were generated during the production process.
[0050] Comparative Example 1 involved a series of steps including crushing, oxidation, reduction, separation, reduction, screening, airflow milling, and acid washing for impurity removal. Compared to Example 1, it omitted the three reduction and secondary crushing steps, directly mixing the unscreened coarse particles with the screened powder for airflow milling. This resulted in incomplete metal dissociation, a significant decrease in recovery rate and powder purity, and poor particle size uniformity. Comparative Example 2 involved a series of steps including crushing, oxidation, reduction, separation, reduction, screening, reduction, reduction, crushing, and acid washing for impurity removal. Compared to Example 1, it eliminated the airflow milling step, only... Crushing with a ball mill cannot produce finely sized powder with uniform particle size, failing to meet the particle size requirements of high-precision processing; Comparative Example 3 uses a traditional wet metallurgical process, achieving tungsten-copper separation only through acid leaching and alkali dissolution, generating large amounts of toxic waste gas and heavy metal wastewater, causing severe environmental pollution, and the metal recovery rate and powder purity are far lower than in Example 1, significantly increasing the overall treatment cost; Example 1 uses a complete process of primary crushing, oxidation, primary reduction, separation, secondary reduction, screening, tertiary reduction, secondary crushing, airflow powdering, and acid washing to remove impurities, combined with a ball mill ( Figure 3 ), oxidation reaction vessel ( Figure 6 ), reduction reactor ( Figure 1 Multi-stage cooling system Figure 7 air jet mill ( Figure 4 ), pickling system ( Figure 5 The synergistic use of these technologies enables efficient and clean recycling of tungsten-copper alloy waste. The resulting tungsten powder and copper powder meet the requirements of a recovery rate of ≥99%, oxygen content of <0.05wt%, and excellent particle size uniformity. Moreover, the entire process generates no waste, which aligns with the concept of green, low-carbon, and circular economic development.
[0051] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production, characterized in that, Includes the following steps: S1 primary crushing: Prepare tungsten-copper alloy waste, crush the waste to obtain tungsten-copper alloy powder; S2 oxidation: Tungsten copper alloy powder is oxidized to obtain a mixed powder of copper oxide and tungsten trioxide; S3 First Reduction: The copper oxide-tungsten trioxide mixed powder is reduced to obtain copper-tungsten trioxide mixed powder; S4 separation: The copper-tungsten trioxide mixed powder is separated to obtain tungsten trioxide powder and copper powder; S5 Secondary Reduction: Tungsten trioxide powder is reduced to obtain tungsten powder; S6 Screening: Use a 100~500 mesh standard sieve to sieve to obtain tungsten powder and copper powder that can pass through the 100~500 mesh standard sieve; S7 triple reduction: Unsieved tungsten powder and copper powder are reduced again; S8 Secondary Crushing: The tungsten powder and copper powder that have passed through step S7 are crushed to obtain tungsten powder and copper powder; S9 Airflow pulverization: The tungsten powder and copper powder obtained in steps S6 and S8 are loaded into an airflow mill for high-pressure airflow pulverization to obtain fine tungsten powder and copper powder with uniform particle size. S10 acid washing and impurity removal: Fine tungsten powder and copper powder are acid washed and dried to obtain tungsten powder and copper powder that can pass through a 200~500 mesh standard sieve.
2. The method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, characterized in that, In step S2, tungsten copper alloy powder is placed in an oxidation reaction vessel. First, oxygen at 0.5 MPa is introduced into the oxidation reaction vessel to increase the oxidation rate of the tungsten copper alloy powder by increasing the pressure. The mixture is kept at 750°C for 1.8 hours. Then, the oxygen pressure is reduced to 0.25 MPa and the mixture is kept at 750°C for 0.5 hours. After cooling, a copper oxide-tungsten trioxide mixed powder is obtained.
3. The method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, characterized in that, In step S3, the copper oxide-tungsten trioxide mixed powder is placed in a reduction reactor, nitrogen gas at 0.25 MPa is introduced into the reduction reactor, and then hydrogen gas at 0.25 MPa is introduced into the reduction reactor. The mixture is kept at 450°C for 1 to 1.5 hours and then cooled to obtain copper-tungsten trioxide mixed powder.
4. The method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, characterized in that, In step S4, the copper-tungsten trioxide mixed powder is placed in a reduction reactor, and nitrogen gas at 0.25 MPa is introduced into the reduction reactor. The reactor is heated to 1000℃ and held for 0.5 to 1 hour until the tungsten trioxide has completely volatilized, leaving copper powder in the reactor. The condensation method uses a multi-stage cooling system to guide the high-temperature flue gas containing tungsten trioxide to a condensation chamber with progressively decreasing temperatures. The first-stage condensation zone is maintained at 650℃, allowing some vapor to initially crystallize and precipitate. Subsequently, the gas enters the second and third-stage condensers, where the temperature is further reduced to 400℃ and below, allowing the remaining vapor to continue to condense into solid particles. Finally, fine and uniform tungsten trioxide powder is obtained in the low-temperature section.
5. In the method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, in step S5, the cooled and collected tungsten trioxide powder is placed in a reduction reactor, nitrogen gas at 0.25 MPa is introduced into the reduction reactor, and then hydrogen gas at 0.25 MPa is introduced into the reduction reactor. The mixture is kept at 720°C for 1.5 to 2 hours, cooled, and tungsten powder is obtained.
6. The method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, characterized in that, In step S7, unsieved tungsten powder and copper powder are placed in a reduction reactor one after the other. Nitrogen gas at 0.25 MPa is introduced into the reduction reactor, followed by hydrogen gas at 0.25 MPa. The reactor is kept at 720°C and 450°C for 2 hours respectively, and then cooled.
7. The method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, characterized in that, In steps S1 and S8, a ball mill is used for crushing.
8. The method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, characterized in that, In step S9, inert gas is used as a high-pressure gas flow, with the gas pressure controlled at 5~7 kPa, which makes the particle size of copper powder and tungsten powder finer, thereby improving the purity of tungsten powder and copper powder.
9. A method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, characterized in that, In step S10, fine tungsten powder and copper powder are soaked in a 10-18% hydrochloric acid solution for 8-10 hours, then rinsed with clean water and dried.
10. A method for recycling copper-tungsten alloy waste based on the principle of in-situ hydrogen production according to claim 1, characterized in that, The tungsten powder and copper powder meet the requirements of recovery rate ≥99%, oxygen content <0.05wt%, and excellent particle size uniformity.