A preparing method of low-oxygen titanium using mesh type crucible

Abstract

A manufacturing method of one aspect can solve the problem that, in the process of manufacturing low-oxygen titanium hydride from off-grade titanium hydride using a metal salt containing magnesium oxide (MgO), the inflow of the magnesium oxide into the container of the metal salt and the discharge of the metal salt and the magnesium from titanium are suppressed, thereby increasing the oxygen content and decreasing the hydrogen content of the low-oxygen titanium hydride and making recycling of the metal salt impossible. Specifically, even when using a metal salt containing a high concentration of magnesium oxide, the metal salt can be smoothly introduced into the container to perform the deoxidation reaction of the off-grade titanium hydride within a short period of time, the metal salt containing the magnesium oxide and the magnesium can be easily separated, and a method for manufacturing low-oxygen titanium hydride (TiH2) can be provided that allows the metal salt containing the magnesium oxide and the magnesium to be reused. According to the above manufacturing method, metal salts and magnesium can be recycled, thereby providing an economical and low-oxygen titanium hydride that can be utilized in aerospace, chemical processes, bio-implantation fields, etc.

Description

Technology Field

[0001] This relates to a method for manufacturing low-oxygen titanium using a mesh-type container. Background Technology

[0003] Titanium (Ti) and its alloys possess excellent properties such as high strength, corrosion resistance, and biocompatibility, making them widely used metals in various fields including aerospace, chemical processes, and bioimplants. The oxygen content in Ti is a determining factor for key mechanical properties, such as tensile strength; as the oxygen content increases, the strength of the metal increases, but brittleness also increases, leading to reduced formability and decreased toughness, which can cause the metal to fracture easily under impact loads. Therefore, the American Society for Testing and Materials (ASTM), an international standard classifying Commercially Pure (CP) grades based on the impurity content in Ti, uses the oxygen content of Ti as a key indicator. In the case of ASTM Grade 1 Ti (oxygen content 0.18 wt% or less), while the strength is lower compared to Ti with relatively high oxygen content, it maintains excellent ductility and toughness, which can improve processability and impact resistance. Due to these characteristics, ASTM Grade 1 Ti can be used in a wide variety of applications, including medical implants and biomaterials, aerospace and marine industries, chemical and semiconductor process equipment, batteries and electronic components.

[0004] The Kroll process, a conventional Ti production process, involves manufacturing Ti by reducing titanium tetrachloride (TiCl4) using magnesium. However, since the reaction between TiCl4 and magnesium (Mg) is a highly exothermic reaction, TiCl4 must be supplied slowly to suppress the temperature rise within the reactor, which leads to reduced productivity. Furthermore, the Kroll process operates in a batch manner and exhibits low productivity with a yield of 1 ton / day per retort. Additionally, there are limitations in producing and using large quantities of Ti, as the process of generating TiCl4 by chlorinating high-grade TiO2 causes environmental problems such as greenhouse gas emissions due to the use of toxic chlorine gas and carbon (C).

[0005] In addition, the Kroll process generates off-grade Ti sponge as a byproduct, which is estimated to account for approximately 10 to 20 percent of the total Ti sponge production. Off-grade Ti sponge contains large amounts of impurities such as oxygen (O) and iron (Fe), and these impurities are almost impossible to remove using conventional remelting technologies. Consequently, off-grade Ti sponge is currently being used at a low cost as a deoxidizer in the steel industry. However, if an efficient method is developed to recycle off-grade Ti sponge for Ti production, it would not only reduce process energy consumption and CO2 emissions but also compensate for the low productivity of Ti.

[0006] The biggest challenge in the recycling of off-grade Ti sponges for Ti production is removing major impurities such as O and Fe. This is because these impurities negatively affect the mechanical properties of the final product. Meanwhile, Fe can contribute as a β-stabilizing element in the manufacture of β-based Ti alloys. In other words, even if some Fe impurities are present, off-grade Ti sponges can be utilized for Ti alloy production if the oxygen concentration within the sponge can be reduced to the ASTM Grade 1 level (0.180 wt%). Therefore, to recycle off-grade Ti sponges for Ti production, it is crucial to develop an efficient deoxidation process capable of reducing the oxygen concentration to 0.180 wt% or less.

[0007] To develop an efficient deoxidation process for off-grade Ti sponges, the inventors investigated a deoxidation reaction using Mg under an atmosphere of mixed argon (Ar) and H2 at 933 to 993 K. The process utilizes titanium hydride (TiH2) powder, prepared by hydrogenating off-grade Ti sponges, as a feedstock for deoxidation, thereby [releasing] the hydrogen activity within the reaction system ( a H There is an advantage in improving the reaction rate through an increase in the reaction specific surface area and an increase in the reaction specific surface area. In addition, ceramic-type TiH2 has a higher oxidation resistance compared to Ti during the acid leaching process performed to recover the product after deoxidation, so it has the advantage of being advantageous for manufacturing low-oxygen titanium.

[0008] However, during the acid leaching process after deoxidation, the loss of the magnesium chloride (MgCl2)-potassium chloride (KCl) mixed salt containing unreacted residual Mg was inevitable. In addition, when the TiH2 starting source was located within the molten salt during deoxidation, the low hydrogen partial pressure within the molten salt ( p H2Due to this, dehydrogenation proceeded, resulting in a mixture of Ti and TiH2, rather than pure TiH2, being obtained as a deoxidation product. However, if residual Mg-containing salts can be separated from the deoxidation product before acid leaching or at the end of the deoxidation reaction, the amount of acid treatment waste liquid generated during the acid leaching process can be reduced, and it is expected that process costs can be reduced through the reuse of the residual Mg-containing salts separated from the deoxidation product. Furthermore, if residual Mg-containing salts are separated from the deoxidation product in a high-temperature hydrogen gas atmosphere, the deoxidation product is exposed to the hydrogen gas atmosphere, thereby allowing for the acquisition of pure TiH2 instead of a mixture of Ti and TiH2. Since ceramic-type TiH2 has higher oxidation resistance to dilute acids compared to Ti, oxygen contamination during acid leaching is reduced. Additionally, when TiH2 is used as a raw material for powder metallurgy instead of Ti, it exhibits a high sintering density due to hydrogen embrittlement, which offers the advantage of further improving the mechanical properties of powder-sintered products compared to the use of Ti.

[0009] Accordingly, a method was considered to use a wire mesh strainer type crucible to separate residual Mg-containing salt from the deoxidized product, thereby significantly reducing the amount of acid waste solution and reusing the separated residual Mg-containing salt in the deoxidation process. However, even in this case, it was confirmed that impurities such as MgO generated during the deoxidation process were included in the residual Mg-containing salt, which limited contact between the molten metal salt and TiH2, increased the deoxidation reaction time, and did not effectively reduce the oxygen concentration in the Ti sponge.

[0010] Accordingly, there is a need to develop a method for producing low-oxygen Ti that effectively reduces the oxygen concentration within the Ti sponge under a short deoxidation reaction time while separating and reusing residual Mg-containing salts containing impurities such as MgO. Prior art literature

[0012] Korean Registered Patent No. 10-2037349 The problem to be solved

[0013] 400 to 3,500 pieces / cm² per unit area at the bottom 2 A step of obtaining a first mixture by mixing off-grade titanium hydride (TiH2), a metal salt containing magnesium oxide (MgO), and magnesium (Mg) under a container having a hole;

[0014] A step of obtaining a second mixture containing titanium (Ti) by separating the metal salt containing magnesium oxide (MgO) and the magnesium (Mg) from the above container;

[0015] The present invention provides a method for producing low-oxygen titanium hydride (TiH2) comprising the step of mixing the above-mentioned second mixture with a gas containing hydrogen.

[0016] Another aspect is to provide a low-oxygen titanium hydride produced by the above-described manufacturing method. means of solving the problem

[0018] One pattern is 400 to 3,500 pieces / cm² per unit area at the bottom. 2 A step of obtaining a first mixture by mixing off-grade titanium hydride (TiH2), a metal salt containing magnesium oxide (MgO), and magnesium (Mg) under a container having a hole;

[0019] A step of obtaining a second mixture containing titanium (Ti) by separating the metal salt containing magnesium oxide (MgO) and the magnesium (Mg) from the above container;

[0020] A method for producing low-oxygen titanium hydride (TiH2) is provided, comprising the step of mixing the above-mentioned second mixture with a gas containing hydrogen.

[0021] The above term "off-grade titanium hydride (TiH2)" means titanium hydride obtained by hydrogenating off-grade titanium sponge having an impurity content in titanium exceeding 1.05 wt%, 1.06 wt%, 1.175 wt%, 1.38 wt%, or 1.5 wt%. The impurities in titanium may be one or more selected from the group consisting of, for example, oxygen (O), iron (Fe), chromium (Cr), manganese (Mn), and nickel (Ni).

[0022] In one embodiment, the off-grade titanium hydride may contain oxygen in an amount of 0.975 to 1.38 wt%, 0.975 to 1.25 wt%, 0.975 to 1.175 wt%, 1.0 wt% to 1.38 wt%, 1.0 to 1.25 wt%, 1.0 to 1.175 wt%, 1.05 wt% to 1.38 wt%, 1.05 to 1.25 wt%, or 1.05 to 1.175 wt%. A manufacturing method according to one aspect corresponds to being able to produce a low-oxygen titanium hydride from a titanium hydride containing a high concentration of oxygen content, for example, 0.975 to 1.38 wt% of oxygen.

[0023] In one embodiment, the container has 400 to 3,500 pieces / cm² per unit area at the bottom. 2 , 400 to 3,000 pieces / cm 2 , 400 to 2,000 pieces / cm 2 , 800 to 3,500 pieces / cm 2 , 800 to 3,000 pieces / cm 2 , 800 to 2,000 pieces / cm 2 , 1,000 to 3,500 pieces / cm 2 , 1,000 to 3,000 pieces / cm 2 , 1,000 to 2,000 pieces / cm 2 It may have holes. The above container has 400 holes / cm² per unit area. 2If it has fewer than 3,500 holes per unit area, the mixing efficiency may decrease in the step of obtaining the first mixture, and the container has 3,500 holes / cm² 2 If the number of holes exceeds [amount], the separation efficiency of the metal salt and the magnesium may be reduced in the step of obtaining the second mixture.

[0024] In one embodiment, the hole in the lower portion may have an average diameter of 30 to 200 μm, 30 to 150 μm, 30 to 120 μm, 70 to 200 μm, 70 to 150 μm, 70 to 120 μm, 80 to 200 μm, 80 to 150 μm, 80 to 120 μm, 100 to 200 μm, 100 to 150 μm, or 100 to 120 μm. If the above container has holes with an average diameter of less than 70 μm, the mixing efficiency may be reduced in the step of obtaining the first mixture, and if the above container has holes exceeding 200 μm, the low-oxygen titanium hydride (TiH2) may be discharged through the holes in the step of obtaining the second mixture containing titanium (Ti) by separating the metal salt containing magnesium oxide (MgO) and the magnesium (Mg) from the above container, thereby reducing the yield of the low-oxygen titanium hydride (TiH2).

[0025] In one embodiment, the average diameter of the off-grade titanium hydride (TiH2) may have a larger average diameter compared to the average diameter of the hole in the bottom portion. For example, if the average diameter of the hole in the bottom portion is 100 μm, the average diameter of the off-grade titanium hydride (TiH2) may be 150 μm, 200 μm, 250 μm, or 300 μm or more. If the average diameter of the off-grade titanium hydride has a smaller average diameter compared to the average diameter of the hole in the bottom portion, the off-grade titanium may be discharged through the hole in the bottom portion, and the yield of the low-oxygen titanium hydride may be reduced.

[0026] In one embodiment, the average diameter of the off-grade titanium hydride may be 50 to 300 μm, 50 to 250 μm, 50 to 200 μm, 50 to 150 μm, 75 to 300 μm, 75 to 250 μm, 75 to 200 μm, 75 to 150 μm, 100 to 300 μm, 100 to 250 μm, 100 to 200 μm, or 100 to 150 μm.

[0027] Meanwhile, the metal salt containing magnesium oxide (MgO) and the magnesium (Mg) may be in a solid state or a molten state. Additionally, when the metal salt containing magnesium oxide and the magnesium are in a solid state, they may have an average diameter larger than the average diameter of the hole at the bottom or an average diameter smaller than the average diameter of the hole. Unlike the off-grade titanium hydride, the metal salt containing magnesium oxide (MgO) and the magnesium (Mg) can pass through the hole in a molten state, and the metal salt containing magnesium oxide (MgO) and the magnesium (Mg) having an average diameter of a wide range may be used. For example, the average diameter of the metal salt containing the magnesium oxide (MgO) or the magnesium (Mg) may be 1 to 20,000 μm, 1 to 10,000 μm, 1 to 5,000 μm, 1 to 3,000 μm, 1 to 1,000 μm, 10 to 20,000 μm, 10 to 10,000 μm, 10 to 5,000 μm, 10 to 3,000 μm, 10 to 1,000 μm, 100 to 20,000 μm, 100 to 10,000 μm, 100 to 5,000 μm, 100 to 3,000 μm, or 100 to 1,000 μm.

[0028] The above term "average diameter" may be the average obtained by summing the diameters of individual particles having different diameters.

[0029] The above "container" may be made of a material that does not dissolve during the manufacturing process of the above low-oxygen titanium hydride (TiH2). Specifically, the container may be made of, for example, stainless steel.

[0030] In one embodiment, the metal salt may further comprise one or more selected from the group consisting of magnesium chloride (MgCl2) and potassium chloride (KCl). Specifically, the metal salt may further comprise only MgCl2 or KCl, and if the metal salt comprises both MgCl2 and KCl, MgCl2 and KCl are in a ratio of 1:0.01 to 0.82, 1:0.01 to 0.7, 1:0.01 to 0.6, 1:0.01 to 0.4, 1:0.05 to 0.82, 1:0.05 to 0.7, 1:0.05 to 0.6, 1:0.05 to 0.4, 1:0.1 to 0.82, 1:0.1 to 0.7, 1:0.1 to 0.6, 1:0.1 to 0.4, 1:0.2 to 0.82, 1:0.2 to 0.7, 1:0.2 to 0.6, or 1:0.2 to It may be included in a weight ratio of 0.4.

[0031] The metal salt is present in a molten state at the step of obtaining the first mixture, which can facilitate the reaction between the off-grade titanium hydride and the magnesium, control the hydrogen chemical potential in the reaction, and increase the reaction rate and diffusion rate.

[0032] In one embodiment, the magnesium oxide (MgO) may be included in excess of 0.16 wt%, 0.3 wt%, 0.5 wt%, or 1 wt% in the metal salt. A manufacturing method according to one aspect corresponds to a method in which, even if the magnesium oxide in the metal salt is included in excess of 1 wt%, the reaction between the off-grade titanium hydride and the magnesium can be carried out smoothly, the off-grade titanium hydride can be deoxidized within a short period of time, and the separation of the metal salt containing the magnesium oxide (MgO) and the magnesium (Mg) can be carried out smoothly in the step of obtaining a second mixture.

[0033] In one embodiment, at the step of obtaining the first mixture, the weight ratio of the off-grade titanium hydride and the metal salt may be 1:1 to 20, 1:1 to 15, 1:1 to 10, 1:2 to 20, 1:2 to 15, 1:2 to 10, 1:5 to 20, 1:5 to 15, or 1:5 to 10.

[0034] In one embodiment, in the step of obtaining the first mixture, the weight ratio of the off-grade titanium hydride and the magnesium may be mixed in a weight ratio of 1:0.25 to 1, 1:0.25 to 0.9, 1:0.25 to 0.8, 1:0.4 to 1, 1:0.4 to 0.9, 1:0.4 to 0.8, 1:0.5 to 1, 1:0.5 to 0.9, or 1:0.5 to 0.8. If the weight ratio of the off-grade titanium hydride and the magnesium is less than 1:0.25, the deoxidation rate of the off-grade titanium hydride decreases, and the oxygen content in the low-oxygen titanium hydride produced by the above manufacturing method may increase. In addition, if the weight ratio of the off-grade titanium hydride and the magnesium exceeds 1:1, the amount of residual magnesium attached to the low-oxygen titanium hydride increases, which may result in increased costs and time for separation.

[0035] In one embodiment, in the step of obtaining the first mixture, the metal salt containing magnesium oxide and the magnesium may be introduced through a hole at the bottom of the container and mixed with the off-grade titanium hydride. When the metal salt containing magnesium oxide and the magnesium are introduced through a hole at the bottom of the container, the metal salt containing magnesium oxide and the magnesium may be in a molten state.

[0036] In one embodiment, the step of obtaining the first mixture may be performed at 923 to 1,046 K, 923 to 1,026 K, 923 to 1,006 K, 933 to 1,046 K, 933 to 1,026 K, 933 to 1,006 K, 943 to 1,046 K, 943 to 1,026 K, or 943 to 1,006 K. If the mixing step is performed at less than 923 K, the magnesium may not melt sufficiently, and the deoxidation rate of the off-grade titanium hydride may decrease, and if the mixing step is performed at more than 1046 K, the oxygen content in the low-oxygen titanium hydride produced by the manufacturing method may increase and the hydrogen content may decrease.

[0037] In one embodiment, the step of obtaining the first mixture may be performed for 3 to 24 hours, 3 to 18 hours, 3 to 12 hours, 6 to 24 hours, 6 to 18 hours, or 6 to 12 hours. A manufacturing method according to one aspect corresponds to being able to produce a low-oxygen titanium hydride having a low oxygen content while shortening the reaction time of the metal salt containing magnesium oxide and the off-grade titanium hydride.

[0038] In one embodiment, the step of obtaining the first mixture may be performed under a gas containing hydrogen. Specifically, the gas containing hydrogen may contain the hydrogen in an amount of 10 to 100 mol%, 10 to 90 mol%, 10 to 80 mol%, 15 to 100 mol%, 15 to 90 mol%, 15 to 80 mol%, 20 to 100 mol%, 20 to 90 mol%, or 20 to 80 mol%. If the hydrogen is contained in the gas in an amount of less than 10 mol%, dehydrogenation of the off-grade titanium hydride may occur, and the hydrogen content in the low-oxygen titanium hydride may decrease.

[0039] Through the step of obtaining the first mixture, hydrogen and oxygen can be removed from the off-grade titanium hydride.

[0040] In one embodiment, the first mixture may comprise titanium (Ti). Specifically, the first mixture may comprise titanium from which hydrogen and oxygen have been removed from the off-grade titanium hydride.

[0041] In one embodiment, the gas may further include an inert gas. Specifically, the gas may further include argon (Ar).

[0042] In one embodiment, the container may have one or more holes with a diameter of 0.1 to 5 mm, 0.1 to 3 mm, 0.1 to 2 mm, 0.5 to 5 mm, 0.5 to 3 mm, 0.5 to 2 mm, 1 to 5 mm, 1 to 3 mm, or 1 to 2 mm in the side portion. Specifically, the container may include one or more, two or more, or four or more holes in the side portion, and the holes in the side portion may be located at a height where the metal salt containing the magnesium oxide and the magnesium can be discharged. If the above container has a hole with a diameter of less than 0.1 mm in the side portion, the efficiency of discharge or inflow of the metal salt containing magnesium oxide (MgO) and the magnesium (Mg) through the hole in the side portion may be reduced due to the surface tension of the molten salt, and if the above container has a hole with a diameter exceeding 5 mm in the side portion, the flow rate of the molten salt may become excessively fast, causing the low-oxygen titanium hydride to be discharged through the side portion, thereby reducing the yield of the low-oxygen titanium hydride.

[0043] In one embodiment, the step of obtaining the second mixture may be performed by discharging the metal salt containing the magnesium oxide (MgO) and the magnesium (Mg) through the hole in the bottom part and the hole in the side part of the container. If the magnesium oxide is included in the metal salt, the magnesium oxide (MgO) may precipitate from the metal salt during the step of obtaining the second mixture, thereby suppressing the discharge of the metal salt and magnesium through the hole in the bottom part of the container; however, if the container has a hole in the side part, the metal salt and magnesium can be discharged through the hole in the side part, thereby allowing the second mixture containing titanium to be easily separated.

[0044] In addition, by having one or more holes with a diameter of 0.1 to 5 mm, 0.1 to 3 mm, 0.1 to 2 mm, 0.5 to 5 mm, 0.5 to 3 mm, 0.5 to 2 mm, 1 to 5 mm, 1 to 3 mm, or 1 to 2 mm in the side portion of the container, it is possible to produce a low-oxygen titanium hydride having a low oxygen content while shortening the reaction time of the metal salt containing magnesium oxide and the off-grade titanium hydride in the step of obtaining the first mixture. In addition, by having one or more holes with diameters of 0.1 to 5 mm, 0.1 to 3 mm, 0.1 to 2 mm, 0.5 to 5 mm, 0.5 to 3 mm, 0.5 to 2 mm, 1 to 5 mm, 1 to 3 mm, or 1 to 2 mm in the side portion of the container, even if the metal salt containing magnesium oxide (MgO) and magnesium (Mg) are reused and reacted with a new off-grade titanium hydride (TiH2), a low-oxygen titanium hydride having a low oxygen content can be produced while shortening the reaction time.

[0045] Through the step of obtaining a second mixture containing titanium, the metal salt containing magnesium oxide and the magnesium can be removed from the first mixture.

[0046] In one embodiment, in the step of mixing the second mixture and a gas containing hydrogen, the gas containing hydrogen may contain the hydrogen in an amount of 10 to 100 mol%, 10 to 90 mol%, 10 to 80 mol%, 15 to 100 mol%, 15 to 90 mol%, 15 to 80 mol%, 20 to 100 mol%, 20 to 90 mol%, or 20 to 80 mol%. If the hydrogen is contained in the gas in an amount of less than 10 mol%, the hydrogen concentration of the low-oxygen titanium hydride may be reduced.

[0047] In one embodiment, the manufacturing method may further include the step of separating low-oxygen titanium hydride from the second mixture after the step of mixing the second mixture and a gas containing hydrogen.

[0048] In one embodiment, the step of separating the low-oxygen titanium hydride may be performed by mixing the second mixture and an acid.

[0049] In one embodiment, the acid may be one or more selected from the group consisting of hydrochloric acid, acetic acid, and nitric acid.

[0050] In one embodiment, the step of separating the low-oxygen titanium hydride may be performed for 0.3 to 2 hours, 0.3 to 1 hour, 0.3 to 0.8 hours, 0.4 to 2 hours, 0.4 to 1 hour, 0.4 to 0.8 hours, 0.5 to 2 hours, 0.5 to 1 hour, or 0.5 to 0.8 hours.

[0051] In one embodiment, the step of separating the low-oxygen titanium hydride may be performed at 273 to 333 K, 273 to 313 K, 273 to 303 K, 288 to 333 K, 288 to 313 K, 288 to 303 K, 293 to 333 K, 293 to 313 K, or 293 to 303 K.

[0052] Through the step of separating the low-oxygen titanium hydride, the metal salt containing magnesium oxide attached to the low-oxygen titanium hydride and magnesium can be removed.

[0053] In one embodiment, the manufacturing method may further include a step of washing the low-oxygen titanium hydride after the step of separating the low-oxygen titanium hydride.

[0054] The above washing may be performed using one or more selected from the group consisting of water and acetone.

[0055] In one embodiment, the manufacturing method may further include a step of drying the mixture after the washing step.

[0056] A manufacturing method of one aspect can solve the problem that, in the process of manufacturing low-oxygen titanium hydride from off-grade titanium hydride using a metal salt containing magnesium oxide (MgO), the inflow of the metal salt into the container during the step of obtaining a first mixture and the discharge of the metal salt and magnesium from titanium during the step of obtaining a second mixture are suppressed, thereby increasing the oxygen content and decreasing the hydrogen content of the low-oxygen titanium hydride and making recycling of the metal salt impossible. Specifically, even when using a metal salt containing a high concentration of magnesium oxide, the metal salt can be smoothly introduced into the container to perform the deoxidation reaction of the off-grade titanium hydride within a short period of time, and the metal salt containing magnesium oxide and the magnesium can be easily separated, thereby providing a method for manufacturing low-oxygen titanium hydride (TiH2) in which the metal salt containing magnesium oxide and the magnesium can be reused. According to the above manufacturing method, metal salts and magnesium can be recycled, thereby providing an economical and low-oxygen titanium hydride that can be utilized in aerospace, chemical processes, bio-implantation fields, etc.

[0058] In one embodiment, the oxygen concentration in the Ti product was measured according to the structure of the crucible's side section. As a result, when the crucible's side section did not contain holes, the titanium hydride contained 0.134 ± 0.008% oxygen when the deoxidation reaction was performed under molten salt that was not reused, and 0.473 ± 0.051% oxygen when the deoxidation reaction was performed under molten salt that was reused. On the other hand, when the crucible's side section contained holes, the titanium hydride contained 0.124 ± 0.010% oxygen when the deoxidation reaction was performed under molten salt that was not reused, and 0.248 ± 0.006% oxygen when the molten salt was reused (see Example 1).

[0060] In another example, XRD analysis of the Ti product was performed according to the structure of the crucible's side section. As a result, it was confirmed that when the crucible's side section did not contain holes, the generated Ti product was a mixture of Ti and TiH2. On the other hand, when the crucible's side section contained holes, it was confirmed that the proportion of Ti in the Ti product was significantly reduced (see Example 2).

[0062] In another embodiment, the crucible was observed before and after the deoxidation reaction according to the structure of the crucible's side section. As a result, it was confirmed that when the crucible's side section did not contain holes, solid salts containing Mg were observed. On the other hand, when a mesh-type crucible containing holes in the side section was used, it was confirmed that the proportion of solid salts containing Mg was significantly reduced even when the molten salt was reused (see Example 3).

[0064] Another aspect provides a low-oxygen titanium hydride produced by the above-described manufacturing method.

[0065] The term "low-oxygen titanium" above refers to titanium with a low oxygen content that possesses high strength, corrosion resistance, and biocompatibility.

[0066] The above term "low-oxygen titanium hydride" refers to TiH2 with a low oxygen content.

[0067] In one embodiment, the oxygen content in the low-oxygen titanium may be 0.166 to 0.573 wt%, 0.166 to 0.495 wt%, 0.166 to 0.458 wt%, 0.166 to 0.441 wt%, 0.2 to 0.573 wt%, 0.2 to 0.495 wt%, 0.2 to 0.458 wt%, 0.2 to 0.441 wt%, 0.350 to 0.573 wt%, 0.350 to 0.495 wt%, 0.350 to 0.458 wt%, or 0.350 to 0.441 wt%.

[0068] Low-oxygen titanium hydrides according to different characteristics have a low oxygen content and possess high strength, corrosion resistance, and biocompatibility, making them suitable for use in aerospace, chemical processes, and bioimplant fields.

[0070] Another aspect provides a material for electronic devices comprising the above-mentioned low-oxygen titanium hydride.

[0071] The above term "low-oxygen titanium hydride" is within the aforementioned range.

[0072] In one embodiment, the electronic device may include a material that requires high strength, corrosion resistance, or biocompatibility. The electronic device may be, for example, an MLCC (multilayer ceramic capacitor), a thin film electrode material, a low-resistance wiring material, a high heat dissipation material, etc.

[0073] An electronic device material containing a low-oxygen titanium hydride according to another aspect is an economical material that possesses high strength, corrosion resistance, and biocompatibility, while requiring low manufacturing costs.

[0075] Another aspect provides an aerospace, chemical process, or bioimplantable material comprising the above-mentioned low-oxygen titanium hydride.

[0076] Specifically, the low-oxygen titanium hydride can be used as an aerospace material requiring high-strength, lightweight metal materials, and specifically, can be used in aircraft, spacecraft, engine parts, etc. In addition, the low-oxygen titanium can be utilized as a material for chemical processes requiring excellent corrosion resistance and heat resistance, and specifically, can be used as a reactor lining, heat exchanger, pipe material, etc. Furthermore, the low-oxygen titanium can be utilized as a bio-implant material such as artificial joints, dental implants, bone graft materials, and stents.

[0077] Materials for aerospace, chemical processes, or bio-implants according to another aspect are materials that possess high strength, corrosion resistance, and biocompatibility, while being economical due to the low cost of manufacturing. Effects of the invention

[0079] A manufacturing method according to one aspect can solve the problem that, in the process of manufacturing low-oxygen titanium hydride from off-grade titanium hydride using a metal salt containing magnesium oxide (MgO), the magnesium oxide leaches out from the metal salt, thereby suppressing the discharge of the metal salt and magnesium from titanium, increasing the oxygen content of the low-oxygen titanium hydride, and making the recycling of the metal salt impossible. Specifically, even when using a metal salt containing a high concentration of magnesium oxide, the deoxidation reaction of the off-grade titanium hydride can be performed within a short time, the metal salt containing magnesium oxide and the magnesium can be easily separated, and a method for manufacturing low-oxygen titanium hydride (TiH2) can be provided that allows for the reuse of the metal salt containing magnesium oxide and the magnesium. According to the manufacturing method, the metal salt and magnesium can be recycled, thereby providing an economical and low-oxygen titanium hydride that can be utilized in aerospace, chemical processes, bio-implantation fields, etc. Brief explanation of the drawing

[0081] Figure 1 is a schematic diagram of a reactor for producing low-oxygen titanium hydride. Figure 2 is a diagram showing the manufacturing process of low-oxygen titanium hydride. Figure 3 is a figure showing the XRD analysis performed on a Ti product that underwent a deoxidation reaction using a crucible that does not contain holes in the side portion. Figure 4 is a figure showing the XRD analysis performed on a Ti product that underwent a deoxidation reaction using a crucible containing a hole in the side. Figure 5 is a diagram showing the internal and bottom shape of a crucible when a deoxidation reaction is performed using a crucible that does not contain holes in the side portion and a metal salt that has not been reused. Figure 6 is a diagram showing the internal and bottom shape of a crucible when a deoxidation reaction is performed by reusing a crucible and a metal salt that does not contain holes in the side portion. Figure 7 is a diagram showing the internal and bottom shape of a crucible when a deoxidation reaction is performed using a crucible containing a hole in the side and a metal salt that has not been reused. Figure 8 is a diagram showing the internal shape of the crucible before and after performing a deoxidation reaction by reusing a crucible containing a hole in the side portion and a metal salt. Specific details for implementing the invention

[0082] The present invention will be explained in more detail below through examples. However, these examples are intended to illustrate the invention and the scope of the invention is not limited to these examples.

[0084] Reference Example

[0085] Reference Example 1. TiH 2 and pretreatment of metal salts

[0086] TiH2 powder obtained by hydrogenating off-grade Ti sponge was used as a raw material for the deoxidation reaction. To produce TiH2, off-grade Ti sponge (VSMPO-AVISMA Corporation) was hydrogenated at MTIG Co., Ltd. at 973 K under H2 gas conditions for 2 hours. Subsequently, the produced TiH2 was ground using a mortar and pestle and then sieved to adjust the particle size. Finally, the particle size of the TiH2 starting source used for deoxidation corresponds to 150 to 300 μm.

[0087] Meanwhile, to remove H₂O contained in the reagents used in the deoxidation reaction, the salts were dried and pre-melted. Magnesium chloride (MgCl₂, anhydrous, purity > 97.0%, Wako Pure Chemical Corporation) and potassium chloride (KCl, anhydrous, purity > 99.0%, KOJUNDO Chemical Laboratory Co., Ltd.) were dried in a vacuum oven (VOS-601SD, EYELA) at 453 K for 72 hours. Subsequently, the dried MgCl₂ and KCl were placed in an Fe container (outer diameter 89 mm, thickness 2 mm, height 200 mm) and pre-melted inside a reactor at 933 K for 2 hours under an argon (Ar) atmosphere.

[0089] Reference Example 2. Preparation of a mesh-type crucible

[0090] (1) Manufacture of a crucible without side holes

[0091] A mesh-type crucible was manufactured, with a mesh-like bottom and no holes in the sides. The crucible was made of Fe material and had dimensions of an outer diameter of 29 mm, a thickness of 2 mm, and a height of 70 mm, with a 100 mesh Ti mesh attached to the bottom (Fig. 1d). Subsequently, the crucible was assembled with a stainless steel cap and tube, installed on the upper flange of the reactor, and positioned on top of the Fe vessel. The upper flange and the main body of the reactor were hermetically joined, and the reactor was mounted inside an electric furnace at 298 K. A schematic diagram of the overall experimental apparatus is shown in Fig. 1a.

[0093] (2) Manufacture of a crucible including a side hole

[0094] A crucible having the same material and specifications as the above-mentioned crucible without a hole in the side portion was manufactured, but additionally, a hole with a diameter of about 2 mm was formed at a height of about 10 to 20 mm from the bottom of the crucible to include a hole in the side portion (Figs. 1b, 1c and 1e).

[0096] Reference Example 3. Analysis Method

[0097] The oxygen concentration (O) of the Ti product was measured using a nitrogen / oxygen / hydrogen analyzer (N / O / H determinator, TCH600, LECO Corporation). In addition, the crystalline phases of the Ti product were identified using an X-ray diffraction analyzer (XRD: X'Pert MPD, PHILIPS, Cu-Kα radiation).

[0099] Experimental Example

[0100] Experimental Example 1. Deoxidation reaction

[0101] Prior to the deoxidation reaction, dried MgCl2 and KCl were placed in an Fe container, and Mg and TiH2 raw materials were loaded into a mesh crucible. The reactor was vacuum-evacuated at 298 K for 15 minutes, after which a mixed gas of Ar gas and 20% H2 was injected to adjust the internal pressure to 1 atm. The internal pressure of the reactor was maintained at 1 atm by continuously supplying the mixed gas until the end of the experiment.

[0102] Afterwards, the reactor was heated to 933 K and maintained at 933 K for 1 hour to pre-melt MgCl2 and KCl, and then the crucible loaded with Mg metal and TiH2 raw material was slowly lowered to a point about 1 mm above the bottom of the reactor and immersed in the molten MgCl2 and KCl to carry out the deoxidation reaction of the TiH2 raw material.

[0103] After the deoxidation reaction was completed, the crucible was raised to a height of 30 mm from the bottom of the Fe container to stop the deoxidation reaction, and the residual Mg-containing molten salt was discharged through the Ti mesh at the bottom of the crucible for 30 minutes. Afterwards, the crucible was further raised to a height of 329 mm from the bottom of the Fe container, the reactor was cooled to 298 K, and the product and residual Mg-containing salt were recovered (Fig. 2).

[0105] Experimental Example 2. Deoxidation reaction using magnesium-containing salt

[0106] After the deoxidation reaction was completed in Experimental Example 1 above, the recovered residual Mg-containing salt was placed back into the Fe container, and the deoxidation reaction of the TiH2 raw material was performed using the same method as in Example 1 above.

[0107] After the deoxidation reaction was completed, the crucible was raised to a height of 30 mm from the bottom of the Fe container to stop the deoxidation reaction, and the residual Mg-containing molten salt was discharged through the Ti mesh at the bottom of the crucible for 30 minutes. Afterwards, the crucible was further raised to a height of 329 mm from the bottom of the Fe container, the reactor was cooled to 298 K, and the product and residual Mg-containing salt were recovered (Fig. 2).

[0109] Experimental Example 3. Hydrochloric acid leaching reaction

[0110] Leaching with HCl was performed to remove Mg, MgCl2, KCl, and generated MgO from the product recovered in Example 1 or Example 2, and to recover the Ti product. Specifically, 1 L of a 10% (v / v) HCl solution was used to leach the product at 298 K for 1 hour without stirring, while the reaction vessel was jacketed and maintained by blowing in Ar gas. Afterward, the residue was filtered and washed with deionized water and acetone. Subsequently, a second leaching was performed under the same conditions using 1 L of a 10% HCl solution for 30 minutes with simultaneous stirring (150 rpm) and Ar gas supply. Afterward, the residue was filtered and washed with deionized water and acetone.

[0112] Examples

[0113] Example 1. Measurement of oxygen concentration in Ti product according to the structure of the crucible side

[0114] A deoxidation reaction of the TiH2 raw material was carried out according to Experimental Examples 1 and 2 using a mesh-type crucible that does not contain holes in the side portion of Reference Example 2, and a leaching reaction was performed according to Experimental Example 3 to separate the Ti product.

[0115] As a result of checking the change in oxygen concentration in the separated Ti product, it was measured that when the deoxidation reaction was performed under molten salt that was not reused according to the method of Experimental Example 1, it contained 0.134 ± 0.008% oxygen, and when the molten salt was reused according to Experimental Example 2, it contained 0.473 ± 0.051% oxygen (Table 1).

[0116] number Deoxidation reaction time (h) Weight ratio of MgCl2 in MgCl2-KCl Oxygen concentration (weight%) in Ti product TiH2 raw material 1.28 1 12 0.75 0.134 ± 0.008 2 12 Reuse 0.473 ± 0.051

[0118] Through this, it was confirmed that when a mesh-type crucible without holes in the side of the crucible is used for deoxidation using reused molten salt, the deoxidation effect is inhibited, and the oxygen concentration in the Ti product after deoxidation deviates significantly from the ASTM Grade 1 level (≤ 0.18 wt%).

[0120] Meanwhile, a deoxidation reaction of the TiH2 raw material was carried out according to Experimental Examples 1 and 2 using a mesh-type crucible containing holes in the side portion of Reference Example 2, and a leaching reaction was performed according to Experimental Example 3 to separate the Ti product.

[0121] As a result, when the deoxidation reaction was performed under molten salt that was not reused according to the method of Experimental Example 1, it was measured to contain 0.124 ± 0.010% oxygen, and when the molten salt was reused according to Experimental Example 2, it was measured to contain 0.248 ± 0.006% oxygen (Table 2).

[0123] number Deoxidation reaction time (h) Weight ratio of MgCl2 in MgCl2-KCl Oxygen concentration (weight%) in Ti product TiH2 raw material 1.28 3 3 0.75 0.124 ± 0.010 4 3 Reuse 0.248 ± 0.006

[0125] Through this, it was confirmed that when a mesh-type crucible containing holes in the side of the crucible is used for deoxidation using reused molten salt, the oxygen concentration in the Ti product after deoxidation can be significantly reduced to the ASTM Grade 2 level (≤ 0.25 wt%), although it deviates somewhat from the ASTM Grade 1 level (≤ 0.18 wt%).

[0126] In addition, considering the deoxidation reaction time, it was confirmed that the oxygen concentration in the Ti product was significantly reduced when using a mesh-type crucible without holes in the side of the crucible and performing the deoxidation reaction for 12 hours, whereas when using a crucible with holes in the side of the crucible and performing the deoxidation reaction for 3 hours, it was confirmed that the TiH2 raw material can be deoxidized in a short time.

[0128] Example 2. XRD analysis of Ti products according to the crucible side structure

[0129] XRD analysis was performed on the Ti product obtained by performing a deoxidation reaction in a crucible that does not contain a hole in the side portion of the crucible mentioned in Example 1 above, or in a crucible that contains a hole.

[0130] As a result, when a crucible without holes in the side portion was used, it was confirmed that both Ti products generated according to Experimental Example 1 and Experimental Example 2 were mixtures of Ti and TiH2. This was because the residual Mg-containing salt inside the crucible after deoxidation was not sufficiently discharged, and the product of the deoxidation reaction was covered by the residual salt, resulting in low p H2 It comes into existence in the atmosphere, and as a result, although the entire reaction system is in a high Ar + 20% H2 mixed gas atmosphere p H Even if this is maintained, the post-deoxidation product is locally low p H2 This corresponds to a situation where Ti generation becomes inevitable when placed in an environment (Fig. 3).

[0131] On the other hand, when a crucible containing holes in the side portions was used, it was confirmed that the proportion of Ti in the Ti product generated according to Experimental Example 2 was significantly reduced (Fig. 4). This is because, as residual Mg-containing salt inside the crucible after deoxidation is discharged through the holes in the side portions, the product of the deoxidation reaction has a high p H2 This is interpreted to be because the hydrogenation reaction was carried out smoothly under conditions of exposure.

[0132] Through this, it was confirmed that when using a mesh-type crucible containing holes on the side of the crucible, a TiH2 phase product can be obtained even when reusing molten salt.

[0134] Example 3. Crucible condition before and after deoxidation reaction according to the side structure of the crucible.

[0135] Meanwhile, when the deoxidation reaction of TiH2 was carried out according to Experimental Examples 1 and 2 using a mesh-type crucible that does not contain holes in the side portion of Reference Example 2, the shape of the interior and bottom portion of the crucible after the deoxidation reaction was observed. As a result, it was confirmed that when the molten salt was not reused, solid salts containing Mg were observed in both the interior and bottom portion of the crucible (Fig. 5), and when the molten salt was reused, solid salts containing Mg were also observed (Fig. 6), and it was confirmed that in all cases, the Ti mesh at the bottom portion of the crucible was blocked.

[0136] Through this, it was confirmed that when using a mesh-type crucible that does not contain holes in the side, even if a mesh-type crucible is used, the Mg-containing solid salt blocks the mesh, preventing the residual Mg-containing salt inside the crucible from being sufficiently discharged, or making it difficult for the residual Mg-containing salt to enter the crucible during the reuse process.

[0138] On the other hand, the deoxidation reaction of TiH2 was carried out according to Experimental Examples 1 and 2 using a mesh-type crucible containing holes in the side portion of Reference Example 2, and as a result of observing the shape of the inside and bottom portion of the crucible after the deoxidation reaction, it was confirmed that the proportion of solid salt containing Mg was significantly reduced even when the molten salt was reused (Figs. 7 and 8).

[0139] Through this, it was confirmed that when using a mesh-type crucible containing holes in the side, Mg-containing solid salt can be discharged through the holes in the side, and a low-oxygen TiH2 product can be obtained even when the molten salt is reused.

Claims

Claim 1 400 to 3,500 pieces / cm² per unit area at the bottom 2 A method for producing low-oxygen titanium hydride (TiH2), comprising the steps of: mixing off-grade titanium hydride (TiH2), a metal salt containing magnesium oxide (MgO), and magnesium (Mg) in a container having holes to obtain a first mixture; separating the metal salt containing magnesium oxide (MgO) and the magnesium (Mg) from the container to obtain a second mixture containing titanium (Ti); and mixing the second mixture with a gas containing hydrogen. Claim 2 A manufacturing method according to claim 1, wherein the hole in the lower portion has an average diameter of 30 to 200 μm. Claim 3 A method of manufacturing according to claim 1, wherein the off-grade titanium hydride contains oxygen exceeding 0.975 weight%. Claim 4 A method of manufacturing according to claim 1, wherein the metal salt further comprises one or more selected from the group consisting of magnesium chloride (MgCl2) and potassium chloride (KCl). Claim 5 A method of manufacturing according to claim 1, wherein the magnesium oxide (MgO) is included in an amount of 0.16 weight% or more in the metal salt. Claim 6 A method of manufacturing according to claim 1, wherein the average particle diameter of the off-grade titanium hydride is 50 to 250 μm. Claim 7 A method of manufacturing according to claim 1, wherein, in the step of obtaining the first mixture, the weight ratio of the off-grade titanium hydride and the metal salt is 1:1 to 20. Claim 8 A method of manufacturing according to claim 1, wherein, in the step of obtaining the first mixture, the weight ratio of the off-grade titanium hydride to the magnesium is 1:0.25 to 1. Claim 9 A method of manufacturing according to claim 1, wherein the step of obtaining the first mixture is performed at 923 to 1046 K. Claim 10 A method of manufacturing according to claim 1, wherein the step of obtaining the first mixture is performed for 3 to 12 hours. Claim 11 A method of manufacturing according to claim 1, wherein the step of obtaining the first mixture is performed under a gas containing hydrogen. Claim 12 A method of manufacturing according to claim 1, wherein the container has one or more holes with a diameter of 0.1 to 5 mm in a side portion. Claim 13 A manufacturing method according to claim 12, wherein the step of obtaining the second mixture is performed by discharging the metal salt containing the magnesium oxide (MgO) and the magnesium (Mg) through the hole in the bottom part and the hole in the side part of the container. Claim 14 A manufacturing method according to claim 1, further comprising the step of separating low-oxygen titanium hydride from the second mixture after the step of mixing the second mixture and a gas containing hydrogen. Claim 15 A manufacturing method according to claim 14, wherein the step of separating the low-oxygen titanium hydride is performed by mixing the second mixture and an acid. Claim 16 Low-oxygen titanium hydride produced by the method of claim 1. Claim 17 A low-oxygen titanium hydride according to claim 16, wherein the low-oxygen titanium contains oxygen in an amount of 0.25 weight% or less.

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