Preparation method of high-purity metal vanadium

Abstract

The invention provides a preparation method of high-purity metal vanadium, which comprises the steps of raw material selection, aluminothermic reduction, electron beam melting equipment configuration, preheating and vacuumizing, electron beam melting, repeated melting and cast ingot forming, specifically, high-purity V2O3, high-purity aluminum powder and potassium chlorate are mixed and subjected to a vacuum aluminothermic reduction reaction under the protection of argon, and the high-purity metal vanadium is obtained; the vanadium-aluminum alloy with the vanadium content of 75% is generated; electron beam melting: focusing a high-energy electron beam on the vanadium-aluminum alloy through an electron gun, melting the high-energy electron beam and dripping the high-energy electron beam into a molten pool; multiple smelting: smelting twice or multiple times, and respectively removing high-vapor-pressure impurities and low-vapor-pressure impurities; cast ingot forming, wherein molten metal obtained after smelting is cooled and crystallized to form a cast ingot; according to the method, the vanadium-aluminum alloy is prepared by optimizing electron beam melting process parameters and combining an aluminothermic reduction method, and efficient and low-cost production of high-purity vanadium metal is achieved.

Description

Technical Field

[0001] The present invention relates to the field of smelting technology, and in particular to a method for preparing high-purity metallic vanadium Background Art

[0002] Vanadium is a refractory metal with a high melting point (1890°C), excellent corrosion resistance, and thermal stability. It is widely used in nuclear reactors, spacecraft, high-temperature alloys, and other fields. However, due to its high melting point and high chemical activity, traditional smelting methods have difficulty producing high-purity vanadium. Electron beam melting technology, which bombards and melts metals with high-energy electron beams in a vacuum environment, can effectively remove impurities and improve the metal's purity and structural uniformity. In recent years, electron beam melting technology has demonstrated significant advantages in the preparation of vanadium metal, becoming one of the key technologies for the industrial production of high-purity vanadium metal. Summary of the Invention

[0003] In view of the above drawbacks, the present invention proposes a method for preparing high-purity metallic vanadium, comprising: Raw material selection: High-purity vanadium trioxide is used as the main raw material, with a purity of ≥99.9%; Aluminothermic reduction: Mix high-purity V2O3, high-purity aluminum powder and potassium chlorate, and carry out vacuum aluminothermic reduction reaction under argon protection to produce vanadium-aluminum alloy with a vanadium content of 75%; Electron beam melting equipment configuration: A low-power electron beam melting furnace with a power range of 80kW to 150kW is used, equipped with a water-cooled copper crucible and a vacuum system to enable the melting process to be carried out in a high vacuum environment; Preheating and vacuuming: Place the vanadium-aluminum alloy into the crucible and vacuumize to 1×10 -3 Pa or above; Electron beam melting: A high-energy electron beam is focused on the vanadium-aluminum alloy through an electron gun, causing it to melt and drip into the molten pool; Multiple smelting: Two or more smeltings are used to remove high vapor pressure impurities and low vapor pressure impurities respectively; Ingot forming: The molten metal is cooled and crystallized to form an ingot; Preferably, the vacuum degree during the smelting process is controlled at 1×10 -4 Pa~1×10 -3 Pa to reduce the introduction of gas impurities.

[0004] Preferably, a preheating treatment is performed before smelting, with a high temperature of 50kW to 60kW and a smelting speed of 5kg / h, to pre-melt the alloy ingot to promote the homogenization of the alloy composition and improve the smelting effect.

[0005] This method optimizes the electron beam melting process parameters and combines the aluminothermic reduction method to prepare vanadium-aluminum alloy, thereby achieving efficient and low-cost production of high-purity vanadium metal. DETAILED DESCRIPTION

[0006] The present invention provides a method for preparing high-purity metallic vanadium, comprising: Raw material selection: High-purity vanadium trioxide is used as the main raw material, with a purity of ≥99.9%; Aluminothermic reduction: Mix high-purity V2O3, high-purity aluminum powder and potassium chlorate, and carry out vacuum aluminothermic reduction reaction under argon protection to produce vanadium-aluminum alloy with a vanadium content of 75%; The reduction reaction of aluminum to vanadium trioxide is as follows: V2O3+AI=2V+AI2O3 The reaction heat is low and cannot make the slag melt and flow, so potassium chlorate flux is added, and the reaction is as follows: KClO3+2AI=KCl+AI2O3 The reaction releases a lot of heat. When the materials react at high temperature, the generated vanadium-aluminum alloy has good fluidity and workability.

[0007] Electron beam melting equipment configuration: A low-power electron beam melting furnace with a power range of 80kW to 150kW is used, equipped with a water-cooled copper crucible and a vacuum system to enable the melting process to be carried out in a high vacuum environment; Preheating and vacuuming: Place the vanadium-aluminum alloy into the crucible and vacuumize to 1×10 -3 Pa or above; Electron beam melting: A high-energy electron beam is focused on the vanadium-aluminum alloy through an electron gun, causing it to melt and drip into the molten pool; due to the high energy density of the electron beam, the impurity elements (such as Al, Fe, Si, etc.) in the molten pool volatilize at high temperature, thereby achieving impurity removal.

[0008] Multiple smelting: Two or more smeltings are used to remove high vapor pressure impurities (such as Al, Fe, Si) and low vapor pressure impurities (O, N, etc.) respectively; Ingot forming: The molten metal is cooled and crystallized to form an ingot. The ingot size can be adjusted according to demand, such as diameter 90mm, 120mm, 140mm, and length above 1000mm.

[0009] Furthermore, the vacuum degree during the smelting process is controlled at 1×10 -4 Pa~1×10 -3 Pa to reduce the introduction of gas impurities.

[0010] Furthermore, a preheating treatment is performed before smelting, with a high temperature of 50kW to 60kW and a smelting speed of 5kg / h, to pre-melt the alloy ingot to promote the homogenization of the alloy composition and improve the smelting effect.

[0011] Impurity element analysis of the alloy produced by this method: quantitative analysis of impurity elements (such as Al, Fe, Si, O, N, etc.) in the ingot is carried out by means of X-ray fluorescence spectroscopy (XRF), inductively coupled plasma optical emission spectroscopy (ICP-OES), etc. to ensure that their content is less than 0.1%.

[0012] The present invention has been described in detail above, but the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the purpose of this patent.

Claims

1. A method for preparing high-purity metallic vanadium, characterized in that: include: Raw material selection: High-purity vanadium trioxide is used as the main raw material, with a purity of ≥99.9%; Aluminothermic reduction: Mix high-purity V2O3, high-purity aluminum powder and potassium chlorate, and carry out vacuum aluminothermic reduction reaction under argon protection to produce vanadium-aluminum alloy with a vanadium content of 75%; Electron beam melting equipment configuration: A low-power electron beam melting furnace with a power range of 80kW to 150kW is used, equipped with a water-cooled copper crucible and a vacuum system to enable the melting process to be carried out in a high vacuum environment; Preheating and vacuuming: Place the vanadium-aluminum alloy into the crucible and vacuumize to 1×10 -3 Pa or above; Electron beam melting: A high-energy electron beam is focused on the vanadium-aluminum alloy through an electron gun, causing it to melt and drip into the molten pool; Multiple smelting: Two or more smeltings are used to remove high vapor pressure impurities and low vapor pressure impurities respectively; Ingot forming: The smelted metal liquid is cooled and crystallized to form an ingot.

2. The method for preparing high-purity metallic vanadium according to claim 1, wherein: The vacuum degree during the smelting process was controlled at 1×10 -4 Pa~1×10 -3 Pa to reduce the introduction of gas impurities.

3. The method for preparing high-purity metallic vanadium according to claim 1, wherein: Preheating treatment is also carried out before smelting. The high temperature is set to 50kW~60kW and the smelting speed is 5kg / h. The alloy ingot is pre-melted to promote the homogenization of the alloy composition and improve the smelting effect.