A process for the production of ferrotitanium alloy from ilmenite or high titania slag in a boron-containing molten oxide system

Abstract

The present application belongs to the technical field of electrolytic synthesis of non-ferrous metals and alloys, and discloses a method for preparing ferrotitanium alloy by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system. A titanium raw material is mixed into a B2O3-CaO-CaF2-SiO2 system after dehydration to form a melt; the melt is placed in a crucible and put into a sealed reactor; a cathode and an anode are put in, and a certain distance is kept between the two, and inert gas protection is provided; the temperature is raised to the working temperature, and electrolysis is carried out for a certain time; the product is taken out after cooling, washed with dilute acid and distilled water, and dried. The addition of B2O3 to the CaO-CaF2-SiO2 system for high-temperature molten oxide electrolysis can accelerate the dissolution of TiO2 in ilmenite and high-titanium slag, reduce the melting point of the molten salt, increase the migration rate of titanium ions, reduce the melt viscosity, and significantly improve the dissolution efficiency of TiO2 and the efficiency of electrolytic titanium.

Description

Technical Field

[0001] This invention relates to the field of electrolytic synthesis technology of non-ferrous metals and their alloys, and in particular to a method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system. Background Technology

[0002] Titanium and titanium alloys possess excellent physicochemical properties and play a vital role in modern industry. Although titanium is abundant on Earth, its complex and costly preparation processes result in high prices, severely limiting its applications. Specifically, the high-temperature, highly corrosive chlorination reaction of TiO2 can severely damage equipment and cause environmental pollution. The use of magnesium in the TiCl4 thermal reduction process leads to high costs, discontinuous operations, and limited yields. Therefore, finding a short-process, low-cost, and efficient method for preparing titanium is crucial to reducing its market price and meeting the urgent needs of various industries.

[0003] Molten salt electrolysis is a method that uses electrochemical methods to obtain metallic titanium and its alloys by electrolysis in a high-temperature melt. Currently, this method is mainly divided into two categories. The first category involves the electrolysis of solid TiO2 in single or multi-element eutectic molten salts such as CaCl2, NaCl, LiCl, and KCl, within a temperature range of 600℃ to 1000℃. The reaction mechanism generally falls into two categories: one utilizes the current collector-TiO2-molten salt three-phase interface for an electrochemical reduction reaction, where, as the reaction proceeds, the three-phase interface continuously expands towards the product Ti-TiO2-molten salt three-phase interface, thus electrolyzing solid TiO2; the other involves electrolyzing Ca in the molten salt. 2+ Ions form metallic Ca, which has high solubility in CaCl2 molten salt and can reduce solid TiO2 to metallic Ti. This method has the advantages of low operating temperature, but O 2- The slow solid-phase diffusion of plasma creates a kinetic bottleneck, resulting in a slow reduction rate and low production efficiency, making it unsuitable for large-scale industrial production. The second method involves electrolyzing molten, ionic TiO2 oxides. TiO2 is added to a CaO-CaF2-SiO2 ternary melt, forming an ionic molten oxide at temperatures above 1300℃ for titanium ion electrolysis. This method improves the electrolysis rate and efficiency to some extent because the electrolysis target is titanium ions. However, this method also has some problems. The main issues are the high melting temperature and viscosity of the melt, especially after the addition of TiO2, which significantly increases the viscosity and severely affects the diffusion rate of titanium ions. Additionally, the slow dissolution rate of TiO2 significantly impacts the production efficiency and rate of the electrolysis process. Therefore, developing a low-viscosity molten oxide system with a high TiO2 dissolution rate is of great significance for the electrolysis of metallic titanium and its alloys. Summary of the Invention

[0004] Based on existing technology, the purpose of this invention is to provide a method for preparing ferrotitanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system. This invention uses ilmenite separated from ilmenite and high-titanium slag (an intermediate smelting product) as raw materials. Based on the existing CaO-CaF2-SiO2 melt, B2O3 is added to the melt to form a multi-component eutectic with CaO, CaF2, SiO2, and TiO2. This improves the dissolution rate and solubility of TiO2, as well as the electrical conductivity of the molten oxide, thereby achieving efficient electrolysis of ilmenite / high-titanium slag in boron-containing molten oxide to prepare ferrotitanium alloys.

[0005] The technical solution of the present invention is as follows: A method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system includes the following steps: Step 1: Treatment of oxide melt; Four raw materials, B2O3, CaO, CaF2 and SiO2, are mixed, vacuum dried and then cooled to room temperature in a furnace to obtain a dehydrated B2O3-CaO-CaF2-SiO2 system. Titanium raw material is then mixed into the dehydrated B2O3-CaO-CaF2-SiO2 system to form an oxide melt. Step 2: Electrode preparation; Carbonaceous material is used as the anode material, and metal is used as the cathode material. A metal rod is used to connect the anode and cathode to form a cathode electrode and an anode electrode. Step 3: Install the electrolysis unit; Place the oxide melt in a crucible and then into a sealed reactor; place the cathode and anode, maintaining a certain distance between them, and introduce inert gas for protection. Step 4: Electrolysis and product post-processing; Heat to the working temperature and electrolyze for a certain period of time; cool down and remove the product, wash it with dilute acid and distilled water, and dry it.

[0006] In the B2O3-CaO-CaF2-SiO2 system after dehydration in step 1, B2O3 accounts for 1%-20% of the mass fraction of the oxide melt, CaO accounts for 5%-45% of the mass fraction of the oxide melt, SiO2 accounts for 5%-35% of the mass fraction of the oxide melt, and CaF2 accounts for 5%~45% of the mass fraction of the oxide melt; the basicity is 0.2~3.0.

[0007] The alkalinity of the B2O3-CaO-CaF2-SiO2 system after dehydration in step 1 is 0.5-2.0.

[0008] The parameters for vacuum drying in step 1 are as follows: drying temperature is 80℃~400℃; drying time is 6 h~48 h; heating rate is 1℃ / min~10℃ / min.

[0009] The drying temperature is 200℃-350℃; the drying time is 12h~30h; and the heating rate is 2℃ / min~5℃ / min.

[0010] In step 3, the distance between the negative electrode and the positive electrode is 0.5 cm to 10 cm.

[0011] In step 3, the distance between the negative electrode and the positive electrode is 2cm-4cm.

[0012] In step 4, the operating temperature is 1250℃-1600℃, and the electrolysis method is constant current or constant voltage. The constant current current density is 5 A·cm⁻¹. -1 -200 A·cm -1 .

[0013] The operating temperature in step 4 is 1350℃-1550℃.

[0014] In step 1, the raw materials are ilmenite and high-titanium slag, an intermediate smelting product.

[0015] Furthermore, in step 1, the B2O3-CaO-CaF2-SiO2 system and the raw materials are mixed by manual mixing, mechanical stirring, and mechanical ball milling. Mechanical ball milling is preferred.

[0016] Furthermore, in step 2, the anode carbonaceous material is glassy carbon and graphite, and the cathode metal material is tungsten, molybdenum, or titanium. The metal rod is tungsten, molybdenum, or titanium.

[0017] Furthermore, the crucible in step 3 is a magnesium oxide, aluminum oxide, boron nitride, or glassy carbon crucible, preferably a magnesium oxide or glassy carbon crucible.

[0018] Furthermore, in step 3, the inert gas is argon and nitrogen, preferably argon.

[0019] Furthermore, the dilute acid used for washing in step 4 is hydrochloric acid or sulfuric acid, preferably hydrochloric acid, with a concentration of 0.5-2.5 mol·L⁻¹. -1 .

[0020] The present invention provides a method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system, the principle of which is as follows: To address the issues of slow dissolution rate, low conductivity, slow titanium ion diffusion rate, and high melt viscosity of TiO2 in the CaO-CaF2-SiO2 system, B2O3 is added to the molten salt. This lowers the activation energy of the TiO2 dissolution process. The addition of B2O3 forms a pentagonal melt, reducing the system's melting point and viscosity, which is beneficial for ion migration. Furthermore, the combination of B2O3 and TiO2 forms complex ions, increasing the conductivity of Ti ions. By controlling the concentration of added B2O3, the reactivity of boron ions is reduced, allowing titanium ions to be reduced before boron. Based on this, using ilmenite, a beneficiation product from vanadium-titanium magnetite, and high-titanium slag after iron removal as raw materials, the above-mentioned CaO-CaF2-SiO2-B2O3 system is used to efficiently dissolve the above-mentioned mineral raw materials and electrolyze them to directly prepare titanium-iron alloys. This facilitates the subsequent separation of iron and titanium to prepare metallic titanium, avoiding the high energy consumption, high cost, and long process of the traditional Kroll method for preparing metallic titanium. The addition of B2O3 can effectively improve the electrolysis efficiency of molten oxide electrolysis of metallic titanium.

[0021] The beneficial effects of this invention are as follows: 1. Adding B2O3 to the CaO-CaF2-SiO2 system of high-temperature molten oxide electrolysis can accelerate the dissolution of TiO2 in ilmenite and high-titanium slag, lower the melting point of molten salt, increase the migration rate of titanium ions, reduce the viscosity of melt, and significantly improve the dissolution efficiency of TiO2 and the efficiency of titanium electrolysis.

[0022] 2. Using ilmenite and high-titanium slag directly as raw materials, titanium-iron alloys can be directly prepared by electrolysis. This provides a foundation for the subsequent preparation of metallic titanium.

[0023] 3. High-temperature molten oxide electrolysis can avoid the high energy consumption, high pollution, high cost and long process of traditional titanium smelting. It has the characteristics of low cost, green and environmentally friendly process, environmental friendliness and high product quality. Attached Figure Description

[0024] Figure 1 The image shows the XRD pattern of the carbon powder synthesized by molten salt in the comparative example of this invention. Figure 2 This is the XRD pattern of the carbon powder synthesized by molten salt chemical synthesis in Example 1 of the present invention. Detailed Implementation

[0025] The present invention will be further described in detail below with reference to the embodiments.

[0026] The CaO, CaF2, SiO2, and B2O3 used in the embodiments of this invention are analytical grade, with a purity of 99%. The raw materials used in the embodiments of this invention are ilmenite and high-titanium slag from Xinjiang. The alumina crucible used in this embodiment of the invention is a commercially available product with a purity of 99% and a diameter of 90 mm. The argon gas used in this invention example is commercially available high-purity argon with a purity of 99.999%. In this embodiment of the invention, high-temperature molten oxides are used as raw materials of CaO-CaF2-SiO2-B2O3, CaO-CaF2-B2O3, CaF2-SiO2-B2O3, and CaO-SiO2-B2O3, and the working temperature is 1350℃-1550℃.

[0027] Comparative Example 1 A method for preparing ferrotitanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system includes the following steps: Step 1: Treatment of oxide molten salt; 460g of four raw materials, namely CaO, CaF2, SiO2 and high-titanium slag, were mixed and placed in an alumina crucible with a diameter of 90mm. The mixture was dried at 300℃ for 12h and then cooled to room temperature in the furnace to obtain a dehydrated oxide melt raw material. The mass ratio of CaO:CaF2:SiO2:high-titanium slag was 150:150:100:40:60. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0028] (3) Place the crucible containing the oxide melt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0029] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1350℃, and keep it at that temperature for 2 hours to dissolve the high-titanium slag.

[0030] (2) Apply 20 mA·cm 2 The current was used for electrolysis for 6 hours.

[0031] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 (20 kHz) to remove salt. Then, it was washed with 0.5 mol / L hydrochloric acid, followed by rinsing with water to remove residual acid. After centrifugation and drying, the product was obtained. After washing and recovery, the product was found to mainly consist of titanates and calcium fluoride, etc. (see appendix) Figure 1 The small amounts of titanium-iron alloy and titanium indicate that the process of preparing titanium-iron alloy by electrolysis of high-titanium slag was essentially not carried out due to the high titanium slag dissolution rate and low titanium migration rate.

[0032] Example 1 A method for preparing ferrotitanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system includes the following steps: Step 1: Treatment of oxide molten salt; Five raw materials, namely CaO, CaF2, SiO2, B2O3, and high-titanium slag, were mixed and placed in an alumina crucible with a diameter of 90 mm. The mixture was dried at 300℃ for 12 h and then cooled to room temperature in the furnace to obtain a dehydrated oxide melt raw material. The mass ratio of CaO:CaF2:SiO2:B2O3:high-titanium slag was 150:150:100:40:60. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0033] (3) Place the crucible containing the oxide melt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0034] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1350℃, and hold for 20min. (2) Apply 20 mA·cm 2 The current was used for electrolysis for 6 hours.

[0035] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 (20 kHz) to remove salt. Then, it was washed with 0.5 mol / L hydrochloric acid and rinsed with water to remove residual acid. After centrifugation and drying, the product was obtained. A black powder was recovered after washing, and XRD diffraction analysis revealed it to be a titanium and titanium-iron alloy (see attached image). Figure 2 This indicates that adding B2O3 to the molten salt significantly improves the dissolution rate of high-titanium slag and the migration rate of titanium ions, enabling the electrolysis reaction to proceed smoothly and yielding titanium-iron alloys and metallic titanium. When the B2O3 content in the molten oxide exceeds 20%, it is in a supersaturated state, and the melting point of the melt will increase significantly, which is detrimental to the electrolytic titanium reaction process.

[0036] Example 2 Step 1: Treatment of oxide molten salt; Five raw materials, namely CaO, CaF2, SiO2, B2O3, and ilmenite, were mixed and placed in an alumina crucible with a diameter of 90 mm. The mixture was dried at 300℃ for 12 h and then cooled to room temperature in the furnace to obtain a dehydrated oxide melt raw material. The mass ratio of CaO:CaF2:SiO2:B2O3:ilmenite was 150:150:100:40:60. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0037] (3) Place the crucible containing molten salt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0038] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1350℃, and hold for 20min. (2) Apply 20 mA·cm 2 The current was used for electrolysis for 6 hours.

[0039] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 to remove salts. The ultrasonic oscillation frequency was 20 kHz. Then, it was washed with 0.5 mol / L hydrochloric acid, and residual acid was washed away with water. After centrifugation and drying, the product was obtained. After washing and recovery, a black titanium-iron alloy powder was obtained.

[0040] Example 3 Step 1: Treatment of oxide molten salt; Five raw materials, namely 500g CaO, CaF2, SiO2, B2O3, and high-titanium slag, were mixed and placed in an alumina crucible with a diameter of 90mm. The mixture was dried at 300℃ for 12h and then cooled to room temperature in the furnace to obtain a dehydrated oxide melt raw material. The mass ratio of CaO:CaF2:SiO2:B2O3:high-titanium slag was 130:130:100:70:70. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0041] (3) Place the crucible containing molten salt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0042] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1400℃, and hold for 20min. (2) Apply 30 mA·cm 2 The current was used for electrolysis for 4 hours.

[0043] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 to remove salts. The ultrasonic oscillation frequency was 20 kHz. Then, it was washed with 0.5 mol / L hydrochloric acid, and residual acid was washed away with water. After centrifugation and drying, the product was obtained. After washing and recovery, a black titanium-iron alloy powder was obtained.

[0044] Example 4 Step 1: Treatment of oxide molten salt; Five raw materials, namely CaO, CaF2, SiO2, B2O3, and ilmenite, were mixed and placed in an alumina crucible with a diameter of 90 mm. The mixture was dried at 300℃ for 12 h and then cooled to room temperature in the furnace to obtain a dehydrated oxide melt raw material. The mass ratio of CaO:CaF2:SiO2:B2O3:ilmenite was 130:130:100:70:70. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0045] (3) Place the crucible containing molten salt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0046] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1400℃, and hold for 20min. (2) Apply 30 mA·cm 2 The current was used for electrolysis for 4 hours.

[0047] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 to remove salts. The ultrasonic oscillation frequency was 20 kHz. Then, it was washed with 0.5 mol / L hydrochloric acid, and residual acid was washed away with water. After centrifugation and drying, the product was obtained. After washing and recovery, a black titanium-iron alloy powder was obtained.

[0048] Example 5 Step 1: Treatment of oxide molten salt; 500g of four raw materials, namely CaF2, SiO2, B2O3 and ilmenite, were mixed and placed in an alumina crucible with a diameter of 90mm. The mixture was dried at 300℃ for 12h and then cooled to room temperature in the furnace to obtain a dehydrated oxide melt raw material. The mass ratio of CaF2:SiO2:B2O3:ilmenite was 200:200:30:70. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0049] (3) Place the crucible containing molten salt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0050] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1450℃, and hold for 20min. (2) Apply 25 mA·cm 2 Electrolysis was carried out for 5 hours at the specified current.

[0051] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 to remove salts. The ultrasonic oscillation frequency was 20 kHz. Then, it was washed with 0.5 mol / L hydrochloric acid, and residual acid was washed away with water. After centrifugation and drying, the product was obtained. After washing and recovery, a black titanium-iron alloy powder was obtained.

[0052] Example 6 Step 1: Treatment of oxide molten salt; 500g of four raw materials, namely CaF2, SiO2, B2O3 and high-titanium slag, were mixed and placed in an alumina crucible with a diameter of 90mm. The mixture was dried at 300℃ for 12h and then cooled to room temperature in the furnace to obtain a dehydrated oxide melt raw material. The mass ratio of CaF2:SiO2:B2O3:high-titanium slag was 200:200:30:70. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0053] (3) Place the crucible containing molten salt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0054] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1450℃, and hold for 20min. (2) Apply 25 mA·cm 2 Electrolysis was carried out for 5 hours at the specified current.

[0055] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 to remove salts. The ultrasonic oscillation frequency was 20 kHz. Then, it was washed with 0.5 mol / L hydrochloric acid, and residual acid was washed away with water. After centrifugation and drying, the product was obtained. After washing and recovery, a black titanium-iron alloy powder was obtained.

[0056] Example 7 Step 1: Treatment of oxide molten salt; Five raw materials, namely 500g CaO, CaF2, SiO2, B2O3, and high-titanium slag, were mixed and placed in an alumina crucible with a diameter of 90mm. The mixture was dried at 300℃ for 12h and then cooled to room temperature in the furnace to obtain a dehydrated oxide melt raw material. The mass ratio of CaO:CaF2:SiO2:B2O3:high-titanium slag was 100:100:120:80:100. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0057] (3) Place the crucible containing molten salt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0058] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1550℃, and hold for 20min. (2) Apply 18 mA·cm 2 The current was used for electrolysis for 10 hours.

[0059] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 to remove salts. The ultrasonic oscillation frequency was 20 kHz. Then, it was washed with 0.5 mol / L hydrochloric acid, and residual acid was washed away with water. After centrifugation and drying, the product was obtained. After washing and recovery, a black titanium-iron alloy powder was obtained.

[0060] Example 8 Step 1: Treatment of oxide molten salt; Five raw materials, namely CaO, CaF2, SiO2, B2O3, and ilmenite, were mixed and placed in an alumina crucible with a diameter of 90 mm. The mixture was dried at 300 °C for 12 h and then cooled to room temperature in the furnace to obtain a dehydrated melt raw material. The mass ratio of CaO: CaF2: SiO2: B2O3: ilmenite was 100:100:120:80:100. Step 2: Preparation for the electrolysis process; (1) Clean the 99% pure molybdenum sheet with deionized water and ethanol by ultrasonic cleaning (power 100W) for 30 minutes each. After drying, connect it with a 2mm diameter molybdenum wire to obtain an electrolytic cathode. (2) After polishing a 10mm diameter graphite rod with 2000# sandpaper, it is ultrasonically cleaned with ethanol (100W power), dried, and then connected to a 2mm diameter molybdenum wire to obtain an electrolytic anode.

[0061] (3) Place the crucible containing molten salt into the alumina reactor, seal the reactor at both ends with stainless steel flanges, cool it with circulating water, and then introduce high-purity argon gas.

[0062] Step 3: Heating and electrolysis; (1) Increase the temperature at 5℃ / min until it reaches 1550℃, and hold for 20min. (2) Apply 18 mA·cm 2 The current was used for electrolysis for 10 hours.

[0063] Step 4: Sample post-processing; The cooled product was removed from the reactor and repeatedly ultrasonically washed with water at pH 7 to remove salts. The ultrasonic oscillation frequency was 20 kHz. Then, it was washed with 0.5 mol / L hydrochloric acid, and residual acid was washed away with water. After centrifugation and drying, the product was obtained. After washing and recovery, a black titanium-iron alloy powder was obtained.

Claims

1. A method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system, characterized in that, The steps include the following: Step 1: Treatment of oxide melt; Four raw materials, B2O3, CaO, CaF2 and SiO2, are mixed, vacuum dried and then cooled to room temperature in a furnace to obtain a dehydrated B2O3-CaO-CaF2-SiO2 system. Titanium raw material is then mixed into the dehydrated B2O3-CaO-CaF2-SiO2 system to form an oxide melt. Step 2: Electrode preparation; Carbonaceous material is used as the anode material, and metal is used as the cathode material. A metal rod is used to connect the anode and cathode to form a cathode electrode and an anode electrode. Step 3: Install the electrolysis device; Place the oxide melt in a crucible and then into a sealed reactor; place the cathode and anode, maintaining a certain distance between them, and introduce inert gas for protection. Step 4: Electrolysis and product post-processing; Heat to the working temperature and electrolyze for a certain period of time; cool down and remove the product, wash it with dilute acid and distilled water, and then dry it.

2. The method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 1, characterized in that, In the B2O3-CaO-CaF2-SiO2 system after dehydration in step 1, B2O3 accounts for 1%-20% of the mass fraction of the oxide melt, CaO accounts for 5%-45% of the mass fraction of the oxide melt, SiO2 accounts for 5%-35% of the mass fraction of the oxide melt, and CaF2 accounts for 5%~45% of the mass fraction of the oxide melt; the basicity is 0.2~3.

0.

3. The method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 1, characterized in that, The alkalinity of the B2O3-CaO-CaF2-SiO2 system after dehydration in step 1 is 0.5-2.

0.

4. The method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 1, characterized in that, The parameters for vacuum drying in step 1 are as follows: drying temperature is 80℃~400℃; drying time is 6 h~48 h; heating rate is 1℃ / min~10℃ / min.

5. The method for preparing ferrotitanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 4, characterized in that, The drying temperature is 200℃-350℃; the drying time is 12h~30h; and the heating rate is 2℃ / min~5℃ / min.

6. The method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 1, characterized in that, In step 3, the distance between the negative electrode and the positive electrode is 0.5 cm to 10 cm.

7. The method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 6, characterized in that, In step 3, the distance between the negative electrode and the positive electrode is 2cm-4cm.

8. The method for preparing ferrotitanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 1, characterized in that, In step 4, the operating temperature is 1250℃-1600℃, and the electrolysis method is constant current or constant voltage. The constant current current density is 5 A·cm⁻¹. -1 -200 A·cm -1 .

9. The method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 8, characterized in that, The operating temperature in step 4 is 1350℃-1550℃.

10. The method for preparing ferro-titanium alloys by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system according to claim 1, characterized in that, In step 1, the raw materials are ilmenite and high-titanium slag, an intermediate smelting product.

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