KR20100076717A - Method of preparing for metal powder - Google Patents

Abstract

PURPOSE: A metal powder producing method is provided to obtain the metal Ti powder of high purity by supplying metal halide and manufacturing metal powder. CONSTITUTION: A metal powder producing method comprises following steps. Metal halide is supplied to the metal halide pipe. The reducing agent is provided to one or more reducing agent supply pipes. The reducing agent is mixed by the suction force of the provided metal halide. The reducing agent supply pipe passes through the metal halide supply pipe.

Description

Method of preparing metal powder {Method of preparing for metal powder}

The present invention relates to a method for producing a metal powder, and more particularly, supplying a metal halide to a metal halide supply pipe, intersecting the supply direction of the metal halide, but one to the metal halide supply pipe It relates to a method for producing a metal powder comprising the step of supplying a reducing agent to the reducing agent supply pipe is mixed.

The mineral component is a metal oxide and is an oxide mineral which is crystalline or amorphous. There has long been a study for obtaining metals from these oxide minerals.

In particular, although the metal Ti density is lower than 60% of steel, there is a slight difference depending on the composition of the alloy, but it has a function as a strong structural material at -180 ~ 500 ° C. In addition to being used, the chemical process industry has a wide variety of uses such as heat exchangers, chemical reactors, pumps and piping. These Tis also exist in the minerals as Ti oxide, from which useful pure Ti or Ti alloys have been obtained.

Currently, in order to prepare Ti from TiCl ₄ , a chlorination process of a Ti oxide ore having a high Ti content is required. Ore, including rutile (rutile, TiO ₂ ), must be physically beneficiated to be continuous and effective in the chlorination process. It is necessary to prepare TiCl ₄ from the starting materials ilmenite (FeTiO ₃ ), titaniferous iron, or other raw ore from which Ti is sourced. On the other hand, a method of using a number of reducing agents such as H, C, Na, K, Ca, Al, Mg has been applied to the process of reducing the TiCl ₄ to form a metal.

However, currently commercialized batch processes exhibit a difference in quality, such as varying the concentration of impurities such as oxygen, nitrogen, iron, etc. of Ti metals produced in each batch with a lot of contamination in handling materials.

As a method of obtaining Ti, both the Kroll process and the Hunter process are sponge Ti reduction process technologies invented before the 1940's. It is applied to mass production and is known as the only way to commercialize Ti. Referring to FIG. 1, in the crawl process 100, TiCl ₄ is chemically reduced by using magnesium (Mg) at a temperature of 700 ° C. to 1000 ° C. FIG. The Hunter process is very similar to the crawl process, except that NaCl (sodium chloride) is produced as a reaction byproduct using Na as the reducing agent instead of Mg.

However, in the conventional Kroll process and the Hunter process, it is difficult to finely control the TiCl ₄ reduction reaction, the reaction is sporadic, and the dendrite growth of the metal Ti generated in the reduction reaction occurs. Ti masses are formed in the container. At this time, the produced Ti is mixed into the magnesium (Mg) or Na molten metal, and produces a reactant called "sponge titanium". When the reactor and the reaction product are cooled, the coagulated and coarse Ti sponge is physically separated from other reaction by-products and unreacted reducing agent materials, pulverized and purified.

The metal mass formed into the desired shape by compressing the sponge to have a higher density is a component of the metal oxide and is an oxide mineral which is crystalline or amorphous. There has long been a study for obtaining metals from these oxide minerals.

Although metal Ti has a lower density than 60% of steel, there is a slight difference depending on the composition of the alloy, but it is used as a strategic structural material at -180 ~ 500 ℃, so it is used for strategic main purposes such as aircraft manufacturing and turbine wings. In addition, in the chemical process industry, the use of heat exchangers, chemical reactors, pumps, piping, etc. is very diverse. These Tis also exist in the minerals as Ti oxide, from which useful pure Ti or Ti alloys have been obtained.

Currently, in order to prepare Ti from TiCl ₄ , a chlorination process of a Ti oxide ore having a high Ti content is required. Ore, including rutile (rutile, TiO ₂ ), must be physically beneficiated to be continuous and effective in the chlorination process. It is necessary to prepare TiCl ₄ from the starting materials ilmenite (FeTiO ₃ ), titaniferous iron, or other raw ores from which Ti is sourced.

On the other hand, a method of using a number of reducing agents such as H, C, Na, K, Ca, Al, Mg has been applied to the process of reducing the TiCl ₄ to form a metal. However, currently commercialized batch processes exhibit a difference in quality, such as varying the concentration of impurities such as oxygen, nitrogen, iron, etc. of Ti metals produced in each batch with a lot of contamination in handling materials.

As a method of obtaining Ti, both the Kroll process and the Hunter process are sponge Ti reduction process technologies invented before the 1940's and are now commercially adopted by the Kroll process for over 50 to 60 years. It is applied to mass production and is known as the only way to commercialize Ti.

Referring to FIG. 1, in the crawl process 100, TiCl ₄ is chemically reduced by using magnesium (Mg) at a temperature of 700 ° C. to 1000 ° C. FIG. The Hunter process is very similar to the crawl process, except that NaCl (sodium chloride) is produced as a reaction byproduct using Na as the reducing agent instead of Mg.

However, in the conventional Kroll process and the Hunter process, it is difficult to finely control the TiCl ₄ reduction reaction, the reaction is sporadic, and the dendrite growth of the metal Ti generated in the reduction reaction occurs. Ti masses are formed in the container. At this time, the produced Ti is mixed into the magnesium (Mg) or Na molten metal, and produces a reactant called "sponge titanium".

When the reactor and the reaction product are cooled, the coagulated and coarse Ti sponge is physically separated from other reaction by-products and unreacted reducing agent materials, pulverized and purified.

When the sponge is compressed to produce a metal ingot shaped to a desired shape with a higher density, a Ti metal ingot is manufactured by melting in a high vacuum arc melting furnace using an electrode. If high purity ingots are required, refining conditions apply to remove impurities during melting through a multi-arc melting process.

Powder Ti is mainly produced from a sponge by crushing, shot casting, centrifugal processes, or the like.

Conventionally known commercialization techniques include a method of preparing a hydrous Ti (TiH ₂ ) having high brittleness by mixing metal Ti with hydrogen, and then preparing the micro Ti through a fine grinding process. Hydrogen-containing powdered Ti hydrate is made of Ti powder to remove hydrogen in a later process to show Ti intrinsic metal properties.

As described above, the process of making Ti powder in a form usable from sponge Ti is very complicated and difficult, labor intensive, and requires a lot of processing time, and thus the production cost increases due to several factors.

In addition, it is pointed out that the quality of purity of Ti ingots formed inside the batch type has locally different quality problems in each batch product and in one batch. In addition, the process has the problem of generating waste at a level that is severe enough to cause environmental problems.

In order to solve this problem, US Pat. No. 6,409,797 was used to obtain metal powder by injecting metal halide vapor into the liquid alkali metal or alkaline earth metal at a reduced speed by reducing the reaction. However, the patented technology should be supplied by applying a separate pressure to the reducing agent, and since the reducing agent is flowed in the middle of the flow of the metal halide, it is not easy to mix the metal halide and the reducing agent. In addition, there is a problem that the alkali metal or alkaline earth metal should be supplied in excess of the chemical ratio.

In addition, the patented technology, the chemical reaction occurs instantaneously rapidly without control of the reaction, the metal halide compound is supplied at a sound velocity and the reducing agent is separated into very small particles, the powder formed after the reduction reaction is very fine metal Ti finally recovered The specific surface area of the powder becomes large. The large surface area of the metallic Ti powder is easily combined with external air and the material of the washing process. For example, the oxygen impurity concentration is 1000 ppm or more, resulting in high contamination.

In order to solve the above problems, the present invention comprises the steps of supplying a metal halide to the metal halide supply pipe and the cross direction of the metal halide supply direction, one or more reducing agent supply pipe to the metal halide supply pipe of the present invention Method according to the aspect includes supplying a metal halide compound to the metal halide supply pipe and the cross direction of the supply of the metal halide compound, the reducing agent is supplied to the metal halide supply pipe to the at least one reducing agent supply pipe is mixed with Provided is a method for producing a metal powder.

Preferably, the reducing agent provides a production method is mixed by the suction force of the metal halide compound supplied.

Preferably, the reducing agent supply pipe is provided through the metal halide supply pipe.

Preferably, the reducing agent supply pipe provides a manufacturing method in which the spray base is formed at the end.

Preferably, the metal halide compound provides a method of supplying a temperature higher than the vaporization temperature.

Preferably, the mixing is provided at a temperature higher than the vaporization temperature of the metal halide, but below the vaporization temperature of the reducing agent provides a manufacturing method.

Preferably, the reducing agent provides a production method comprising an alkali metal or alkaline earth metal.

Preferably, the metal in the metal halide is selected from the group consisting of Ti, Al, As, Sb, Sn, Be, B, Ta, Ge, V, Nb, Mo, Ga, Ir, Os, U and Re. It provides a manufacturing method.

The present invention simplifies the process by continuously manufacturing the metal powder, eliminating the separate separation, purification and crushing process, and reduces the production cost by reducing the process time has the effect of efficient and energy saving. In addition, the metal powder produced according to the present invention has the effect of having a certain quality. In addition, in the case of preparing the metal powder according to the present invention, a harmless salt is prepared as a reaction by-product, which does not cause environmental pollution.

In addition, the present invention does not need to apply a separate pressure when supplying a reducing agent, and the reducing agent is easily mixed with the metal halide compound and does not need to be supplied in excess. In addition, the present invention is economical because it is possible to control the reaction to obtain a metal Ti powder of relatively high purity.

The method for producing a metal powder according to the present invention comprises the steps of supplying a metal halide compound to the metal halide supply pipe and the supply direction of the metal halide compound, the liquid reducing agent is supplied to at least one reducing agent supply pipe to the metal halide supply pipe And mixing.

The metal powder to be obtained by the present invention can be obtained from a compound of the metal and a halogen element (metal halide compound). The metal is a transition metal or a typical metal, and is selected from the group consisting of Ti, Al, As, Sb, Sn, Be, B, Ta, Ge, V, Nb, Mo, Ga, Ir, Os, U and Re. Further, the halogen element is selected from the group consisting of fluorine, chlorine, bromine and iodine. The metal halide compound is preferably a high purity compound of 99.8% or more.

The metal halide compound may be supplied into the reactor through a supply pipe in a gaseous state. The metal halide in the gas phase has a certain flow, and the reaction may be controlled by adjusting the flow.

In addition, the metal halide compound is preferably supplied at a temperature higher than the vaporization temperature, for example, in the case of TiCl ₄ When vaporized over 137 ℃, but obtain a higher reactivity with TiCl ₄ it can be made 150 ℃.

In addition, preferably, the metal halide compound may be supplied through the supply pipe by mixing an inert gas into a transfer medium for the purpose of adjusting the concentration or adjusting the flow rate.

The supply pipe is preferably made of an organic or inorganic material that does not react or bond with the metal halide to be transferred. The feed pipe may be preferably formed through the reactor, and those skilled in the art may change the diameter and material of the feed pipe according to the scale of the desired product.

In the present invention, the metal halide is reduced with a reducing agent to obtain a desired metal. The reducing agent includes an alkali metal or an alkaline earth metal. Examples of the alkali metal include lithium, sodium, potassium, rubidium, cesium, and francium, and examples of the alkaline earth metal include beryllium, magnesium, calcium, strontium, barium, and radium.

Magnesium, calcium, and sodium in the reducing agent react with the metal halide to form salts of magnesium chloride, calcium chloride, and sodium chloride as reaction by-products, and the salts do not cause environmental pollution. It is preferable to select and use.

In the reducing agent, sodium has a higher ionization tendency than magnesium or calcium, and thus, the reduction reaction is more likely to occur, and the melting point tends to become liquid at around 100 ° C. Therefore, sodium is most preferably used as the reducing agent.

In addition, the reducing agent is preferably supplied in the liquid phase. For example, when the reducing agent is Na, the Na is evaporated at 877 ° C., so it is preferably less than 877 ° C. When the reducing agent is in the gas phase, it is preferable to supply the liquid phase because it is difficult to control the reaction and there is a risk of explosion.

The reducing agent may be preferably supplied through a supply pipe. The deployable and concurrently operable numbers of the reducing agent feed can be selected according to the desired compound, amount, scale, and the like. In addition, the inner diameter of the metal halide compound supply pipe and the inner diameter of the reducing agent supply pipe may be changed according to the chemical equivalence ratio between the reactants and the condition of the required product.

The supply pipe of the reducing agent may cross the supply direction of the metal halide compound, and the liquid reducing agent may be supplied to the metal halide compound supply pipe and mixed with one or more reducing agent supply pipes. When the crossing is based on the supply direction of the metal halide compound, the crossing angle with the reducing agent supply pipe may be more than 0 °.

In addition, the crossing angle may be supplied differently for each supply pipe when using a plurality of supply pipes. In addition, the reducing agent supply pipe may be formed through the metal halide compound supply pipe. In addition, the ends of each of the reducing agent supply pipe and the metal halide compound supply pipe may be arranged to cross at a predetermined distance.

3 and 4 showing cross-sections of the reactor as one embodiment of the reactor of the present invention, the crossing of the reducing agent supply pipe and the metal halide compound supply pipe will be described in more detail.

The supply direction of the metal halide compound supply pipes 301 and 401 and the direction of the reducing agent supply pipes 302 and 402 for supplying a liquid reducing agent are positioned to cross each other. The metal halide gas is supplied into the reactors 300 and 400 through the metal halide supply pipes 301 and 401. The liquid reducing agent is supplied into the reactors 300 and 400 through the reducing agent supply pipes 302 and 402.

Referring to FIG. 3, which shows an embodiment of the metal halide supply pipe and the reducing agent supply pipe of the present invention, one end of the metal halide supply pipe 301 may be coupled to penetrate the end of the reducing agent supply pipe 302. When the metal halide is ejected through the supply pipe, suction force is generated by the fluid of the metal halide compound, and thus the reducing agent is introduced into the metal halide supply pipe and mixed without additional pressure from the reducing agent supply pipe.

In addition, referring to FIG. 4 as another embodiment of the present invention, the metal halogen supply pipe 401 and the reducing agent supply pipe 402 may be ejected at a predetermined distance without being coupled to each other. Also in this case, suction force is generated by the fluid of the metal halide compound, whereby the reducing agent is introduced into the metal halide compound and mixed without a separate supply pressure.

In addition, it is possible to form the separation plates 403 and 303 in order to increase the reaction rate of the reactants that participate in the reaction by better mixing of the metal halide compound ejected into the metal halide supply pipe and the reducing agent ejected from the reducing agent supply pipe.

In addition, the reducing agent supply pipe may be preferably formed with an injection substrate at the end of the reducing agent supply pipe so that the reducing agent is injected. The injector base may be in the form of a tube bundle formed of several pores.

When the metal halide flows from the metal halide supply pipe disposed to intersect with the reducing agent supply pipe, the pressure around the metal halide fluid is lowered, and thus a suction force for sucking the reducing agent from the reducing agent supply pipe is generated. In addition, due to the suction force, a reducing agent is introduced into the metal halide and mixed to cause a reduction reaction.

The suction force causes the reducing agent to come out of the reducing agent supply pipe by the flow rate or feed rate of the metal halide compound. This is effective and economical because it can cause the action of mixing between the reactants without applying a supply pressure to the reducing agent supply pipe separately.

As described above, the metal halide crosses the reducing agent, and the reducing agent is mixed with the metal halide to cause a reduction reaction.

The reduction reaction is represented by the following Chemical Formula 1.

 MX + R → M + RX

Wherein MX is a metal halide, R is a reducing agent, M is a metal, and RX is a salt.

The reaction is preferably made at a temperature of 150 ℃ to 877 ℃. As described above, the metal halide must be maintained at 150 ° C. or higher to smoothly react with the metal halide. In addition, the temperature range is preferable because the temperature of the reducing agent is less than 877 ° C. so that the reducing agent does not evaporate, thereby preventing the reducing agent from rapidly reacting and causing explosion.

The reduction reaction is preferably maintained in an inert atmosphere of 1 atmosphere or more by an inert gas. The inert gas may be preferably selected from argon (Ar), helium (He) and the like.

As described above, the reason for maintaining at 1 atm is to prevent the inflow of external nitrogen or oxygen to prevent oxidation of the generated pure metal. The reaction furnace can change the material, form, structure and the like of the reactor according to the desired compound, amount, scale and the like.

In addition, the reduction reaction may be made by continuously supplying the metal halide and then supplying a reducing agent, or vice versa by continuously supplying the metal halide.

The reaction yields a metal having a particle or powder form and having a size in the range of about 0.05 to 2 mm. The metals obtained are obtained in the form of powders or particles that are independent of each other, and are hardly obtained in a bulk form. Thus, the grinding step is unnecessary.

The metal is obtained as a mixture of a by-product salt and an unreacted metal halide compound and a reducing agent. However, the salt can easily separate the metal by the respective physical and chemical properties, it can omit the step of separating the reaction by-products, unreacted products.

For example, the metal halide compound, the reducing agent, and the salt are water soluble, so that water-soluble properties can be used. For example, Ti obtained by one embodiment of the present invention is not dissolved in water, but TiCl ₄ , Na, NaCl is easily dissolved in water, so that Ti can be easily separated. Furthermore, since TiCl ₄ is a liquid at room temperature but Na and NaCl are solids, NaCl and the unreacted Na and TiCl _{4, which} are reaction byproducts, can be separated and recycled using this property.

2 is a manufacturing process diagram for preparing a metal powder from a metal metal halide compound or a mixture thereof applied to the present invention. Hereinafter, the present invention will be described in more detail with reference to the drawings. Although a metal halide is used as TiCl ₄ and a reducing agent is used as an example, it demonstrates, but this does not limit this invention, It aims at understanding this invention more fully.

Referring to FIG. 2, a mixture of Ti Ore and coke is chlorinated as shown in Chemical Formula 2 through a chlorination apparatus to obtain a pure metal, prepared as TiCl ₄ , and accumulated in a metal halide reservoir.

TiO ₂ Ore + Coke + 2Cl ₂ → TiCl ₄ + O ₂

TiCl ₄ vapor is produced by passing the liquid TiCl ₄ through a TiCl ₄ heater and stored in a metal halide gas reservoir.

The TiCl ₄ vapor is injected into the reactor by adjusting the pressure and flow rate. Liquid Na is supplied from the reducing agent reservoir in a direction intersecting with the direction in which TiCl ₄ is supplied to the reactor.

The reaction furnace removes air containing oxygen, nitrogen, and the like inside, and maintains at least 1 atm by injecting a gas in an inert atmosphere.

The Na is dissolved in a reducing agent melting furnace for dissolving Na from a reducing agent storage container to react with TiCl ₄ , which is the metal halide compound.

After the reduction reaction is performed in the reactor as shown in Formula 3, unreacted TiCl ₄ , Na, a product Ti, and a reaction byproduct NaCl are produced.

TiCl ₄ + 4Na → Ti + 4NaCl

The NaCl is cooled and formed into particles while flying a predetermined distance in the supply direction of the reactant.

The TiCl ₄ , Na, metal Ti, NaCl is passed through the product separation device and the Ti powder is collected in the metal powder collection tank, the unreacted Na is transferred to the reducing agent storage container and recovered again.

The metal Ti may be commercialized through an additional purification process, and the unreacted reducing agent and reaction by-product may be reused through the purification decomposition process. For example, NaCl, a by-product, is decomposed into chlorine gas and Na through electrolysis, so that chlorine gas is recovered by a chlorination device and Na is recovered into a reducing agent storage container for reuse.

Example

High purity (> 99.8%) TiCl ₄ was heated from the storage vessel through a heat exchanger to 200 ° C., higher than the vaporization temperature. The reactor was maintained at a pressure of 1 atm or higher by Ar gas, and the TiCl ₄ gas heated in the reactor was adjusted to a flow rate of 5 to 10 L / min and supplied to the metal halide supply pipe.

Na, which can reduce the TiCl ₄ , was supplied as a liquid phase to a liquid phase through a reducing agent supply pipe crossing the supply pipe of the metal halide compound. In contact with the TiCl ₄ gas as the Na reducing liquid was contacted to produce a metal Ti powder having a particle size of 0.05 ~ 2mm and the concentration of oxygen impurities in the range 500 ~ 800 ppm and NaCl particles as a reaction by-product.

1 is a view showing a conventional batch reactor,

2 is a manufacturing process chart for preparing a metal powder from a metal halide compound or a mixture thereof applied to the present invention,

3 is a cross-sectional view showing a reactor of the present invention,

4 is a cross-sectional view showing a reactor of the present invention.

<Description of the symbols for the main parts of the drawings>

300, 400: reactor 301, 401: metal halide compound supply pipe

302, 402: reducing agent supply pipe 403, 303: separation plate

Claims (8)

Supplying a metal halide to a metal halide supply pipe; And Crossing with the supply direction of the metal halide compound, the reducing agent is supplied to the metal halide compound supply pipe to one or more reducing agent supply pipe is mixed Method for producing a metal powder comprising a. The method of claim 1, wherein the reducing agent is mixed by the suction power of the metal halide to be supplied. The method of claim 1, wherein the reducing agent supply pipe is formed through the metal halide supply pipe. The method of claim 1, wherein the reducing agent supply pipe is characterized in that the spray substrate is formed at the end. The method of claim 1, wherein the metal halide is supplied at a temperature higher than the vaporization temperature. The method of claim 1, wherein the mixing is performed at a temperature higher than the vaporization temperature of the metal halide compound but below the vaporization temperature of the reducing agent. The method of claim 1 wherein the reducing agent comprises an alkali metal or an alkaline earth metal. The metal halide of claim 1, wherein the metal is selected from the group consisting of Ti, Al, As, Sb, Sn, Be, B, Ta, Ge, V, Nb, Mo, Ga, Ir, Os, U, and Re. Selected method.

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