Recycling method of metal vanadium turning waste

Abstract

The invention provides a recycling method of metal vanadium turning waste, and relates to the technical field of metallurgy, and the recycling method of the metal vanadium turning waste comprises the following steps: S1, treating wire-coil-shaped turning waste, S2, vacuumizing and preheating the treated turning waste, S3, heating and degassing, S4, adding elemental iodine to start iodination, and S5, generating volatile vanadium iodide. And S6, the metal vanadium with the purity being 99.95% or above is obtained, the metal vanadium turning waste can be effectively recycled and reused through the iodination purification technology, due to the wire-coil-shaped structure and gaps of the waste, the iodination reaction is smoothly conducted, and the product quality is improved. The efficient utilization of the waste is promoted, the iodination method utilizes the selective effect of iodine to transfer the metal vanadium from a low-temperature area to a high-temperature area for deposition, so that separation and purification are realized, and the high-value recovery of the metal vanadium turning waste is successfully realized.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy, in particular to a method for recycling metal vanadium turning waste. Background Art

[0002] Vanadium metal is a rare metal with strategic significance, which is widely used in high-tech fields such as aerospace and aviation. Pure vanadium metal generally refers to vanadium with a purity between 99.0% and 99.9%, and vanadium with a purity exceeding 99.9% is called high-purity vanadium metal. High-purity vanadium metal has excellent properties such as high melting point, hydrogen storage, good processing performance, strong high-temperature creep resistance, small neutron absorption cross section, and corrosion resistance to liquid sodium. In recent years, the research on vanadium targets in the fields of flat panel displays, glass and decorative coatings, magnetic data storage, semiconductors and microelectronics, solar photovoltaics, etc. has increased, and the demand for vanadium targets has also increased day by day.

[0003] Vanadium target is a high-purity metal vanadium material. During the preparation process, it is necessary to first use an electron beam furnace to melt metal vanadium plates, then weld the metal vanadium plates together, and use an electron beam ingot furnace to melt them into metal vanadium ingots. The metal vanadium ingots are processed into metal vanadium targets for further use. Due to the electron beam melting process, the impurity content on the surface of the metal vanadium ingot is relatively high, and the surface of the ingot needs to be turned to a certain depth, which will generate a large amount of metal vanadium turning waste. At present, the turning waste rate of metal vanadium ingots is 5%-15%. How to recycle the large amount of metal vanadium turning waste in a high-value manner is a difficult problem facing metal vanadium processing companies. Due to the high impurity content, surface oxidation and stains of metal vanadium turning waste, it cannot be directly recycled. Summary of the invention

[0004] 1. Technical issues to be resolved In view of the shortcomings of the prior art, the present invention provides a method for recycling metal vanadium turning waste to solve the problem of difficulty in recycling metal vanadium turning waste in the prior art.

[0005] (II) Technical solution To achieve the above objectives, the present invention is implemented through the following technical solutions: a method for recycling metal vanadium turning waste, specifically comprising the following steps: S1. The wire coil-shaped turning waste is cut to a length of less than 50 mm, the surface oxide layer is treated with dilute hydrochloric acid, then rinsed with deionized water, and placed in a resistance furnace for drying; S2. Add the processed turning waste into the iodine furnace, start the vacuum pump to evacuate, and start the diffusion pump to preheat; S3. When the vacuum degree is less than 1×10-2Pa, the mother wire is heated and degassing begins; S4. When the vacuum degree reaches 1×10-3Pa, stop evacuating and add elemental iodine to start iodination; S5. During the iodination process, crude vanadium in the low temperature zone reacts with iodine vapor at 700-1000°C to generate volatile vanadium iodide. The volatile vanadium iodide in the high temperature zone decomposes into metallic vanadium and iodine vapor on the mother wire at 1100-1500°C. The metallic vanadium is deposited on the surface of the mother wire, and the iodine vapor returns to the low temperature zone to continue iodination. S6. When the furnace temperature drops to about 25°C, take out the iodinated metal vanadium rod to obtain metal vanadium with a purity of more than 99.95%. The remaining crude vanadium is cleaned and dried again for the next iodination.

[0006] Preferably, the concentration of the dilute hydrochloric acid in S1 is controlled at 1-5 mol / l, the drying temperature of the resistance furnace is controlled at 80-120° C., and the drying time is controlled at 1-2 h.

[0007] Preferably, the iodine addition amount of S4 is controlled at iodine:crude vanadium=1:(30-100).

[0008] (III) Beneficial effects The present invention provides a method for recycling metal vanadium turning waste. It has the following beneficial effects: The present invention proposes an innovative iodination purification technology, which is specifically used for recycling and reusing metal vanadium turning waste. Considering that the waste generated by metal vanadium during the turning process is usually in the form of wire coils, these wire strips will form a certain gap after being cut, and this structure provides extremely convenient conditions for the iodination reaction. Utilizing this feature, the present invention can efficiently utilize these wastes, thereby realizing the recovery and reuse of metal vanadium. Since metal vanadium turning waste usually contains a high proportion of impurities, traditional recovery methods are often difficult to achieve the ideal purity. However, the iodination method can transfer metal vanadium from a low temperature area to a high temperature area for deposition by selectively utilizing the chemical properties of iodine. This process can not only effectively separate metal vanadium, but also further purify it, thereby significantly improving the purity of metal vanadium. Specifically, the iodination method controls the reaction conditions so that iodine reacts chemically with metal vanadium to generate volatile vanadium iodine compounds. These compounds will decompose at high temperatures to release pure vanadium metal, while impurities remain in the low temperature area. Through this method, the purity of the metal vanadium finally obtained can reach more than 99.95%, or even higher. This high-purity vanadium metal not only has a higher market value, but also exhibits more excellent performance in industrial applications. Therefore, the present invention not only solves the problem of recycling metal vanadium turning waste, but also realizes the high-value recycling of metal vanadium turning waste through efficient iodination purification technology. This not only helps to reduce environmental pollution, but also provides high-purity vanadium metal for related industries, with significant economic and social benefits. DETAILED DESCRIPTION

[0009] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example 1

[0010] The embodiment of the present invention provides a method for recycling metal vanadium turning waste, which specifically comprises the following steps: S1. Cut the wire-like turning waste to a length of less than 50 mm, and then use a diluted hydrochloric acid solution to treat the surface oxide layer. Ensure that the concentration of the dilute hydrochloric acid is between 1 and 5 mol per liter to achieve the best treatment effect. After treatment, rinse thoroughly with deionized water to remove residual hydrochloric acid. Then, place the cleaned waste in a resistance furnace for drying, with the temperature controlled between 80 and 120°C and the drying time maintained at 1 to 2 hours. Through this series of pretreatment steps, the oxide layer and impurities on the metal surface can be effectively removed, thereby improving the purity and recovery rate of metallic vanadium.

[0011] S2. After completing the above pretreatment steps, the treated turning waste is placed in the iodination furnace. First, the vacuum pump is started to evacuate to create a vacuum environment. Subsequently, the diffusion pump is turned on for preheating to further increase the vacuum degree. The vacuum environment helps to improve the efficiency of the iodination reaction and reduce the occurrence of side reactions, thereby ensuring the smooth progress of the reaction.

[0012] S3. When the vacuum degree reaches less than 1×10^-2Pa, the mother wire is heated and degassed. The degassing step helps to reduce the impact of gas impurities on subsequent reactions, thereby improving the purity of metallic vanadium. Through this process, it can be ensured that no additional impurities are introduced during the reaction, further improving the quality of metallic vanadium.

[0013] S4. When the vacuum reaches 1×10^-3Pa, stop the vacuum operation. At this time, add an appropriate amount of elemental iodine for iodination reaction. The amount of iodine added should be controlled at a ratio of iodine to crude vanadium of 1: (30-100) to ensure efficient reaction. Accurately controlling the amount of iodine added can significantly improve the efficiency of the reaction and the recovery rate of metallic vanadium, thereby improving the overall production efficiency.

[0014] S5. During the iodination process, crude vanadium in the low temperature zone reacts with iodine vapor at 700 to 1000°C to generate volatile vanadium iodide. Subsequently, in the high temperature zone, volatile vanadium iodide decomposes at 1100 to 1500°C to form metallic vanadium and iodine vapor. The metallic vanadium is deposited on the surface of the mother wire, while the iodine vapor returns to the low temperature zone to continue the iodination reaction. By controlling the reaction conditions in different temperature zones, the effective deposition of metallic vanadium and the recycling of iodine vapor are achieved, thereby improving resource utilization and production efficiency.

[0015] S6. When the furnace temperature drops to about 25°C, take out the iodinated metal vanadium rod. At this point, metal vanadium with a purity of more than 99.95% can be obtained. The remaining crude vanadium is cleaned and dried again so that it can be used again in the next iodination process. Through this series of post-processing steps, the high purity of the metal vanadium is ensured, and the recycling of crude vanadium is achieved, effectively reducing the production cost. This process not only improves the utilization rate of resources, but also meets the requirements of sustainable development, and has good economic and environmental benefits.

[0016] Specifically, the 20kg truncated vanadium ingot turning material is surface pickled with dilute hydrochloric acid with a concentration of 1.2mol / l, then rinsed with deionized water, placed in a resistance furnace at 80°C, and dried for 2 hours for standby use. The treated turning material is added to the furnace body, the vacuum pump is turned on to evacuate, and the diffusion pump is turned on for preheating. When the vacuum degree is less than 1×10-2Pa, the mother wire is heated and degassing begins. When the vacuum degree reaches about 1×10-3Pa, the vacuum is stopped, and 250g of elemental iodine is added to start iodination. During the iodination process, the crude vanadium in the low temperature zone reacts with iodine vapor at 780°C to generate volatile vanadium iodide, and the volatile vanadium iodide in the high temperature zone decomposes into vanadium and iodine vapor at 1420°C on the mother wire, and vanadium is deposited on the surface of the mother wire to form a metallic vanadium product. After the iodination reaction is completed, the crystallized vanadium rod is taken out when the furnace temperature is cooled to room temperature, and 15.3kg of metallic vanadium with a purity of 99.96% is obtained. Example 2

[0017] The 30kg truncated vanadium ingot turning material was pickled on the surface with dilute hydrochloric acid with a concentration of 2.5mol / l, then rinsed with deionized water, placed in a resistance furnace and heated to 120℃, dried for 1 hour and set aside. The treated turning material was added to the furnace body, the vacuum pump was turned on to evacuate, and the diffusion pump was turned on for preheating. When the vacuum degree was less than 1×10-2Pa, the mother wire was heated and degassed. When the vacuum degree reached about 1×10-3Pa, the vacuum was stopped, and 520g of elemental iodine was added to start iodination. During the iodination process, the crude vanadium in the low temperature zone reacted with iodine vapor at 830℃ to generate volatile vanadium iodide, and the volatile vanadium iodide in the high temperature zone decomposed into vanadium and iodine vapor at 1350℃ on the mother wire, and vanadium was deposited on the surface of the mother wire to form a metallic vanadium product. After the iodination reaction was completed, the crystallized vanadium rod was taken out when the furnace temperature cooled to room temperature, and 25.8kg of metallic vanadium with a purity of 99.98% was obtained. Example 3

[0018] The 32kg truncated vanadium ingot turning material was pickled on the surface with dilute hydrochloric acid with a concentration of 4.3mol / l, then rinsed with deionized water, placed in a resistance furnace and heated to 100℃, dried for 1.4 hours and set aside. The treated turning material was added to the furnace body, the vacuum pump was turned on to evacuate, and the diffusion pump was turned on for preheating. When the vacuum degree was less than 1×10-2Pa, the mother wire was heated and degassed. When the vacuum degree reached about 1×10-3Pa, the vacuum was stopped, and 560g of elemental iodine was added to start iodination. During the iodination process, the crude vanadium in the low temperature zone reacted with iodine vapor at 900℃ to generate volatile vanadium iodide, and the volatile vanadium iodide in the high temperature zone decomposed into vanadium and iodine vapor on the mother wire at 1330℃, and vanadium was deposited on the surface of the mother wire to form a metallic vanadium product. After the iodination reaction was completed, the crystallized vanadium rod was taken out when the furnace temperature cooled to room temperature, and 18.5kg of metallic vanadium with a purity of 99.97% was obtained.

[0019] Finally, through the analysis of Examples 1-3, the present invention reveals the effectiveness of recycling metal vanadium turning waste using the iodination purification method. In view of the wire-like characteristics of metal vanadium turning waste, there are gaps between the truncated wire strips, which provides convenient conditions for the iodination reaction, so that these wastes can be efficiently utilized. Due to the high impurity content in metal vanadium turning waste, the iodination method can selectively use iodine to transfer metal vanadium from the low temperature zone to the high temperature zone for deposition, effectively realizing the separation and purification of metal vanadium. Through this method, the purity of metal vanadium can reach more than 99.95%, successfully realizing the high-value recycling of metal vanadium turning waste.

[0020] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for recycling metal vanadium turning waste, characterized in that: The specific steps include: S1. The wire coil-shaped turning waste is cut to a length of less than 50 mm, the surface oxide layer is treated with dilute hydrochloric acid, then rinsed with deionized water, and placed in a resistance furnace for drying; S2. Add the processed turning waste into the iodine furnace, start the vacuum pump to evacuate, and start the diffusion pump to preheat; S3. When the vacuum degree is less than 1×10-2Pa, the mother wire is heated and degassing begins; S4. When the vacuum degree reaches 1×10-3Pa, stop evacuating and add elemental iodine to start iodination; S5. During the iodination process, crude vanadium in the low temperature zone reacts with iodine vapor at 700-1000°C to generate volatile vanadium iodide. The volatile vanadium iodide in the high temperature zone decomposes into metallic vanadium and iodine vapor on the mother wire at 1100-1500°C. The metallic vanadium is deposited on the surface of the mother wire, and the iodine vapor returns to the low temperature zone to continue iodination. S6. When the furnace temperature drops to about 25°C, take out the iodinated metal vanadium rod to obtain metal vanadium with a purity of more than 99.95%. The remaining crude vanadium is cleaned and dried again for the next iodination.

2. The method for recycling metal vanadium turning waste according to claim 1, characterized in that: The concentration of the dilute hydrochloric acid in S1 is controlled at 1-5 mol / l, the drying temperature of the resistance furnace is controlled at 80-120° C., and the drying time is controlled at 1-2 h.

3. The method for recycling metal vanadium turning waste according to claim 1, characterized in that: The amount of iodine added to S4 is controlled at iodine:crude vanadium=1:(30-100).