WO2005035806A1

WO2005035806A1 - METHOD FOR PRODUCING Ti OR Ti ALLOY THROUGH REDUCTION BY Ca

Info

Publication number: WO2005035806A1
Application number: PCT/JP2004/014734
Authority: WO
Inventors: Tadashi Ogasawara; Makoto Yamaguchi; Masahiko Hori; Toru Uenishi; Yuko Urasaki; Kazuo Takemura
Original assignee: Sumitomo Titanium Corporation
Priority date: 2003-10-10
Filing date: 2004-10-06
Publication date: 2005-04-21
Also published as: AU2004280401A1; EP1683877A1; EP1683877A4; AU2004280401C1; US20070131057A1; AU2004280401B2

Abstract

A method for producing Ti or a Ti alloy using the reduction by Ca, which comprises a reduction step of holding a molten salt containing CaCl2 and having Ca dissolved therein in a reaction vessel (1) and reacting Ca in the molten salt with a metal chloride containing TiCl4, to generate Ti particles or Ti alloy particles in the molten salt, and a separation step (7) of separating Ti particles or Ti alloy particles being formed in the molten salt from the molten salt. It is preferred to further add an electrolysis step (8) of electrolyzing the CaCl2 withdrawn out of the reaction vessel (1) into Ca and Cl2 and using the formed Ca for the reaction in the reaction vessel (1) for forming Ti or a Ti alloy. In the electrolysis step (8), the use of an alloy electrode comprising a molten Ca alloy as a cathode is effective for the improvement of electric current efficiency and the molten Ca alloy can also be utilized effectively as a medium for transporting Ca in order to enhance a Ca concentration. The above method allows the production of a metallic Ti having high purity with good efficiency at a low cost.

Description

Method for producing Ti or Ti alloy by Ca reduction

Technical field

[0001] The present invention relates to a metal chloride containing TiCl, which is treated with Ca to reduce metal Ti or a Ti alloy.

Four

The present invention relates to a method for producing Ti or a Ti alloy by reducing Ca to be produced.

Background art

[0002] As an industrial production method of metal Ti, a chlor method of reducing TiCl with Mg is generally used.

Four

is there. In this Kroll method, metal Ti is produced through a reduction step and a vacuum separation step. In the reduction step, TiCl, which is the raw material of Ti, is reduced by Mg in the reaction vessel and sponge-like.

Four

Metal Ti is produced. In the vacuum separation step, sponge-like unreacted metal T produced in the reaction vessel and MgCl as a by-product are removed.

2

[0003] Explaining the reduction step in detail, in this step, a reaction vessel is filled with molten Mg, and a TiCl liquid is supplied to the liquid surface from above. As a result, near the liquid level of molten Mg

Four

TiCl is reduced by Mg to form particulate metal Ti. Generated metal Ti is successively below

Four

Settles toward At the same time, the force of by-produced molten MgCl near the liquid surface

The specific gravity of 22 is larger than the specific gravity of molten Mg. Due to this difference in specific gravity, the by-product molten MgCl

Settles in 2 and molten Mg appears on the surface instead. By this specific gravity difference substitution, the molten Mg is continuously supplied to the liquid surface, and the reaction is continued.

[0004] In the production of metal Ti by the Kroll method, it is possible to produce a high-purity product.

However, the manufacturing cost increases due to the notch type, and the product price becomes extremely high. One of the causes of the increase in manufacturing cost is that it is difficult to increase the supply rate of TiCl. TiCl

There are three possible reasons why the supply speed in 4 is limited.

[0005] In order to increase the productivity by the Kroll method, the supply rate of TiCl, which is a raw material of Ti,

Four

It is effective to increase the amount of Mg supplied to the liquid surface per unit area per unit time. However, if the supply rate is set too high, the above-mentioned rate of specific gravity difference replacement cannot keep up, and MgCl will remain on the liquid surface and TiCl will be supplied to it, so the TiCl utilization efficiency will decrease.

2 4 4 As a result, the unreacted product gas (such as TiCl gas or TiCl) These are called unreacted gases) and are discharged out of the reaction vessel. In addition, the generation of unreacted gas must be avoided because it causes a sharp rise in the internal pressure of the vessel. For these reasons, there is a limit to the supply rate of TiCl, which is a raw material for Ti.

Four

[0006] When the supply rate of TiCl is increased, the amount of Ti precipitated on the inner surface of the container above the liquid level increases.

Four

Become. Since the liquid level of molten Mg rises intermittently as the reduction reaction progresses, the precipitated Ti force on the inner surface of the upper part of the vessel is immersed in the molten Mg in the latter half of the reduction reaction, the effective area of the Mg liquid level decreases, and the reaction rate decreases. I do. To suppress this, TiCl

4 It is necessary to limit the feed rate to suppress Ti precipitation on the inner surface of the upper part of the vessel. Another countermeasure for suppressing Ti precipitation on the inner surface of the upper part of the vessel is disclosed in Japanese Patent Application Laid-Open No. Hei 8-295955, but is not sufficient.

[0007] In the Kroll method, the reaction is performed only in the vicinity of the liquid surface of the molten Mg liquid in the reaction vessel, so the heat generation area is small. Therefore, TiCl

If you supply 4, cooling will not be in time. This is another major reason why the supply rate of TiCl is limited.

Four

[0008] Although this is not a problem that directly affects the supply rate of TiCl, the crawl method does not

Four

Ti is generated in the form of particles near the liquid surface and settles. However, due to the wettability (stickiness) of the molten Mg, the generated Ti powder settles in an agglomerated state, and during the sedimentation, it sinters due to the temperature of the melt, grows grains, and is collected outside the reaction vessel. Is difficult. For this reason, continuous production is difficult and productivity is hindered. This is precisely the reason why Ti is produced as a titanium sponge in a batch in a reaction vessel.

[0009] Regarding Ti production methods other than the Kroll method, other than Mg as a reducing agent for TiCl,

Four

It is described in U.S. Pat. No. 2,205,854 that Ca can be used. As a method for producing Ti using a reduction reaction with Ca, a molten salt of CaCl is placed in a reaction vessel.

2 Hold the molten salt to supply the Ca metal powder with the upward force to dissolve Ca into the molten salt and supply the downward force TiCl gas to dissolve Ca and TiCl in the CaCl molten salt.

The method of reacting 4 2 4 is described in US Pat. No. 4,820,339.

[0010] In the reduction by Ca, the reaction represented by the chemical formula (i) generates a TiCl metal Ti, which is

Four

Is by-produced. Ca has a stronger affinity for C1 than Mg. In principle, it is a reducing agent for TiCl.

Suitable for 2 4. In particular, in the method described in U.S. Pat. Use by dissolving in molten CaCl. Using the Ca reduction reaction in molten CaCl

twenty two

As in the case of the Kroll method, TiCl is supplied to the liquid level of the reducing agent in the reaction vessel,

Four

The reaction field expands compared to the case where the reaction field is limited, and the heat generation area expands and cooling becomes easier.Thus, the supply rate of TiCl, which is the raw material for Ti, can be greatly increased, and the productivity is greatly improved.

Four

Can be expected.

[0011] TiCl + 2Ca → Ti + 2CaCl · · (i)

4 2

[0012] However, the method described in US Patent No. 4,820,339 cannot be feasible as an industrial Ti production method. This is because metal Ca powder is used as a reducing agent. That is, since the metal Ca powder is extremely expensive, if it is purchased and used, the manufacturing cost is higher than the crawl method in which the supply rate of TiCl is limited. In addition

Four

The fact that highly reactive Ca is very difficult to handle is also a major factor that hinders the industrial process of producing Ti by Ca reduction.

[0013] Still another Ti production method is the Olson method described in US Patent No. 2,845,386. This is an oxide that directly reduces TiO with Ca without passing through TiCl

4 2

It is a kind of direct reduction method. Although the direct oxide reduction method is highly efficient, it is not suitable for producing high-purity Ti. Because expensive high-purity TiO must be used

2

Power.

Disclosure of the invention

[0014] An object of the present invention is to provide a method for economically producing high-purity metal Ti or Ti alloy with high efficiency and without using an expensive reducing agent.

[0015] To achieve this purpose, the present inventors consider that Ca reduction of TiCl is indispensable.

Four

Dissolve in a molten salt of CaCl as described in the aforementioned U.S. Pat.No. 4,820,339.

2

Understand the use of Ca. Ca dissolves about 1.5% in CaCl.

If the reduction reaction of TiCl by Ca in 22 is used, the supply rate of TiCl can be increased as described above.

4 4

There is a possibility that it can be increased significantly and the production volume can be dramatically increased.

In the production of Ti by this Ca reduction, Ca in the molten salt is consumed in the reduction reaction vessel along with the progress of the reaction of the chemical formula (i), but in order to compensate for this, In the method described in U.S. Pat.No. 4,820,339, powder of metallic Ca is placed in a reduction reaction vessel. Need to keep supplying.

The present inventors consider that in order to industrially establish a method for producing Ti by Ca reduction, it is necessary to economically replenish Ca in the molten salt consumed in the reduction reaction. As means, we devised a method of using Ca generated by electrolysis of molten salt and a method of using and circulating Ca by this. In other words, Ca in the molten salt is consumed during the reduction reaction, but when the molten salt is electrolyzed, Ca is generated in the molten salt.If the Ca thus obtained is reused for the reduction reaction, This eliminates the need for external Ca supplementation. In this method, Ca is not required to be taken out by itself, so that the economic efficiency is improved. It is very difficult to extract Ca alone as a solid, but it is relatively easy to produce Ca in the molten salt.

The present invention has been made on the basis of a powerful idea, and is a method for producing Ti or a Ti alloy by the following Ca reduction (1), (2) or (3).

(L) A molten salt containing CaCl and in which Ca is dissolved is held in a reaction vessel, and the molten salt

2

Of Ti and Ti alloy particles in the molten salt by reacting a metal chloride containing TiCl with Ca

Four

A method for producing Ti by Ca reduction including a reducing step of generating and a separation step of separating Ti particles or Ti alloy particles generated in the molten salt from the molten salt (hereinafter referred to as a `` first production method '' ).

(2) A method for producing Ti or a Ti alloy using a reduction reaction with Ca, comprising CaCl

2 The molten salt in which Ca is dissolved is held in the reaction vessel, and Ca in the molten salt contains TiCl.

4 For the reduction step of reacting the metal salt ridden product to produce Ti or Ti alloy in the molten salt, the molten metal used for producing the Ti or Ti alloy and drawn out of the reaction vessel A combination of a circulating electrolysis process in which salt is electrolyzed to generate and replenish Ca in the molten salt and return to the reaction vessel, and in the electrolysis process, an alloy electrode capable of forming a molten Ca alloy is used as a cathode in the electrolysis process Manufacturing method of Ti or Ti alloy by Ca reduction (hereinafter referred to as “second manufacturing method”).

(3) A method for producing Ti or a Ti alloy using a reduction reaction with Ca, comprising CaCl

(2) The molten salt is electrolyzed using a molten Ca alloy as a cathode to increase the Ca content in the molten Ca alloy. The molten Ca alloy is brought into contact with molten salt containing CaCl to dissolve Ca in the molten salt.

2

The metal containing TiCl is added to the molten salt in which Ca is dissolved by the Ca replenishing process

Four

A method for producing Ti or Ti alloy in a molten salt by supplying a salted sardine and producing Ti or Ti alloy in a molten salt. ).

[0022] The first production method includes a reduction step of generating Ti particles or Ti alloy particles in the molten salt, and a separation step of separating the generated Ti particles or Ti alloy particles from the molten salt. However, as described later, CaCl by-produced with the formation of Ti or Ti alloy

2

An embodiment may be adopted in which Ca is extracted to the outside and electrolyzed to generate Ca and used for a Ti or Ti alloy formation reaction (that is, a TiCl reduction reaction). The second manufacturing method is

Four

The feature of the dissolving step is that an alloy electrode that also has a molten Ca alloy force is used for the cathode. In the first and second production methods, when Ca is used in a circulating manner, a molten CaCl salt having an increased Ca concentration is circulated between the reduction step and the electrolysis step.

2

[0023] The third production method is similar to the second production method in that a molten Ca alloy electrode is used in the electrolysis step. However, when the Ca is circulated and used, the Ca content is increased. It is characterized in that molten Ca alloy is used as a Ca transport medium.

[0024] The first and second methods utilizing a reduction reaction with Ca and circulating a molten salt of CaCl.

2

The method of manufacturing was initially named "Ogasawara" by taking the initials of "Ogasawara, Yamaguchi, Takahashi and Kanazawa" who were deeply involved in the development and completion of the idea. /

[0025] In the first to third production methods, Ti particles are reduced by Ca reduction in a molten salt containing CaCl.

2

Since the generation is performed, the reduction reaction field expands, and at the same time, the heat generation region also expands. Furthermore, the vapor pressure at 850 ° C is very low, with 6.7 kPa (50 mmHg) for Mg and 0.3 kPa (2 mmHg) for Ca. Due to this difference in vapor pressure, the amount of Ti deposited on the inner surface of the upper part of the vessel is much smaller for Ca than for Mg. As a result, in the first to third manufacturing methods, the Ti C1 supply speed can be significantly increased.

Four

[0026] Further, Ca is inferior in wettability (adhesiveness) to Mg, and Ca adhering to precipitated Ti particles is CaC 1

Since it is dissolved in 2, sintering with less aggregation of the produced titanium particles is also overwhelmingly less. As a result, the generated Ti can be taken out of the reaction vessel in a powder state, and continuous Ti production operation can be performed. Work is also possible.

In the first to third production methods, a molten salt containing CaCl (hereinafter simply referred to as a molten salt or a molten salt)

2

Metal chloride containing TiCl in Ca dissolved in molten CaCl solution (hereinafter simply referred to as TiCl)

2 4 4). Furthermore, in the first production method, the molten CaCl

It does not prevent holding the molten Ca liquid on the two liquids. Rather, the molten Ca solution is placed on the molten CaCl solution.

2

By holding, Ca can be supplied from the Ca liquid layer to the CaCl liquid layer below, increasing the reaction efficiency.

2

It becomes possible. In addition, the reduction reaction can be performed even in the molten Ca solution, and from this point, the reaction efficiency can be improved.

[0028] In the first to third production methods, the supply form of TiCl into the molten CaCl solution is as follows.

twenty four

The direct supply of TiCl in the gaseous state to the molten CaCl solution is not suitable for Ca in the molten CaCl solution.

It is especially desirable because the contact efficiency of TiCl is high.

4 2 supplies gaseous TiCl, or measures the liquid level of molten Ca liquid held on molten CaCl

4 2

It is also possible to supply liquid or gaseous TiCl in the liquid.

Four

[0029] Further, regarding the supply of TiCl into the molten CaCl solution, the Ca reduction method of TiCl

4 2 4

The following interesting facts were found in comparison with the Kroll method by Mg reduction.

[0030] In the Kroll method using Mg reduction, a TiCl liquid is supplied to the liquid surface of the molten Mg liquid.

Four

In the past, TiCl gas could be supplied into the molten Mg solution to expand the reaction field.

Four

it was thought. However, as described above, since the vapor pressure of Mg is large, Mg vapor enters the supply nozzle and reacts with TiCl to block the supply pipe. Also, Ti in the molten MgCl solution

4 2

Even if the gas of C1 is supplied, the problem of nozzle clogging still remains. Because the supply pipe is closed

Four

Although the frequency of clogging is reduced, the melt is agitated by TiCl

Four

This is because molten Mg may reach. And above all, TiCl in molten MgCl solution

Even if supplied, Mg does not dissolve in the melt, so that the precipitation reaction of Ti hardly occurs.

[0031] On the other hand, in the Ca reduction method of TiCl, the TiCl gas is supplied into the molten CaCl solution.

4 2 4

In this case, blockage of the supply nozzle hardly occurs. For this reason, the TiCl gas

It is possible to supply 24 and supply of TiCl gas into the molten Ca solution. Nozzle clogged

Four

In particular, the reason may be that the vapor pressure of molten Ca is low.

[0032] That is, in the first to third production methods utilizing the Ca reduction of TiCl, TiCl is melted. It is particularly desirable to supply the salt directly in gaseous form, but this form of supply is feasible without any problems in practical commerce. In addition, liquid or gas of TiCl is supplied to the liquid level of molten salt,

Four

Supplying TiCl liquid and gas to the liquid surface and liquid of molten Ca liquid held on molten CaCl liquid

2 4 is possible without any problems.

[0033] In the first to third production methods, in the reduction step (the Ti generation step by the reduction reaction in the third production method corresponds to the reduction step), Ca is dissolved in the molten salt. By the reduction reaction, granular or Z or powdered Ti or Ti alloy (hereinafter, also referred to as Ti particles or Ti alloy particles) is generated in the reaction vessel.

[0034] Regarding the handling of Ti particles or Ti alloy particles generated in the molten salt, it is also possible to separate the molten salt in the reaction vessel. However, in that case, the operating capacity will be the S batch method. In order to increase the productivity, it is preferable to take out the generated Ti in the form of particles, withdraw the Ti together with the molten salt out of the reaction vessel, and separate the Ti particles from the molten salt outside the vessel. Ti particles can be easily separated from the molten salt force by squeezing operation by mechanical compression. The first manufacturing method includes the separation step, and the second and third manufacturing methods can also employ such an embodiment.

[0035] In the reduction step, CaCl is by-produced at the same time as Ti is generated in the molten salt. In other words,

2

Solution Ca concentration decreases and CaCl increases. As a result, CaCl

2 2 Therefore, it is desirable to extract CaCl in the container to the outside of the container. Ca is used for Ti generation.

2

Extraction at the stage after the removal, that is, when the Ca dissolved in CaCl is consumed.

2

Desirable. The extracting operation is performed in the second manufacturing method, and an embodiment in which the extracting operation is performed in the first manufacturing method can be adopted. However, in the third production method, since the molten Ca alloy is used as a Ca transfer medium as described above, the extraction of the molten salt is not performed.

[0036] The extracted CaCl is electrolyzed into Ca and C1, and

twenty two

It is more desirable to replenish the Ca of the molten salt whose Ca concentration has decreased with the reduction reaction. In addition, it is desirable that the Ti particles or Ti alloy particles formed in the molten salt are drawn out of the reaction vessel together with the molten salt, and the molten salt after the Ti particles or Ti alloy particles are separated is similarly treated. The second production method includes this circulation type electrolysis step, and the first production method also operates in an embodiment having this step. [0037] The molten salt having the Ca concentration recovered in this way is returned to the reduction step, and this is repeated to produce Ti or a Ti alloy. Here, the phenomenon that occurs with respect to Ca is basically only an increase or decrease in the dissolved Ca concentration in the molten salt during the circulation process, and does not require an operation of extracting or supplementing Ca alone. Accordingly, high-purity metal Ti or Ti alloy can be produced economically with high efficiency and without using expensive reducing agents.

[0038] The third production method also includes a Ca generation step by electrolysis of a molten salt containing CaCl,

2

Although a Ca replenishing step is provided to replenish Ca of the molten salt having a reduced Ca concentration, as described later, the first point is that the molten Ca alloy is used as a Ca transfer medium when replenishing the Ca of the molten salt. Or, it is different from the second manufacturing method.

[0039] In the first to third production methods, the current efficiency in the electrolysis step has a large effect on economics, and furthermore, the success or failure of establishing industrial production technology. One of the major causes of the reduction in current efficiency in this electrolysis process is the unreacted dissolved Ca in the molten salt sent to the electrolysis process in the reduction process. In other words, in the reduction step, the reduction reaction proceeds in the molten salt in the reaction vessel, and the dissolved Ca in the molten salt, which is the reducing agent, is consumed, but is not completely consumed. It cannot be avoided that unreacted dissolved Ca is contained in the molten salt obtained.

[0040] In the electrolysis step, as the reactions shown in chemical formulas (ii) and (iii) proceed, Ca is generated on the cathode side, and C1 gas is generated on the anode side. Ca generated on the cathode side does not move to the anode side

2

This can be achieved by using, for example, a diaphragm. However, if dissolved Ca is contained in the molten salt sent to the electrolysis process, it is difficult to eliminate the Ca near the anode. This Ca reacts with the generated C1 and returns to CaCl due to the back reaction. During electrolysis

twenty two

Current efficiency decreases.

[0041] 2Cl— → 2e— + C1 (anode) · · (ii)

2

Ca ²⁺ + 2e "→ Ca (cathode) · · (iii)

That is, the presence of Ca in the molten salt adversely affects the electrolysis step of replenishing the force Ca which is indispensable in the reduction step.

[0043] In the second manufacturing method, an alloy electrode made of a molten Ca alloy (hereinafter, referred to as a cathode) is used as a cathode in the electrolysis step.

, A molten Ca alloy electrode, or simply an alloy electrode). As a result, the The adverse effects of unreacted dissolved Ca in the resulting molten salt can be eliminated as much as possible. In this case, the molten salt in the electrolytic cell, and the interface between the molten Ca alloy and the molten salt constituting the alloy electrode are separated by a partition wall and divided into an anode side and an anti-anode side. It is desirable to introduce a salt to the anti-anode side.

[0044] As described above, when the molten salt on the anode side is electrolyzed as substantially containing no dissolved Ca, C1 gas is generated on the surface of the anode, and the molten Ca alloy forming the cathode and the molten Ca alloy constitute the cathode.

2

Is generated at the interface with the molten salt on the side, and the generated Ca is absorbed by the molten Ca alloy electrode. The molten salt on the anode side contains no or little dissolved Ca, and the above-described back reaction and the accompanying decrease in current efficiency do not occur.

On the other hand, the molten salt on the anti-anode side is a molten salt fed to the reduction step, and contains unreacted dissolved Ca, though not so much. At the interface between the alloy electrode (cathode) and the molten salt on the opposite side of the anode, Ca is released from the alloy electrode (cathode) to the molten salt on the opposite side of the anode. That is, only the anode side in the electrolytic cell is an electrolysis region, and on the anode side, Ca is efficiently generated by electrolysis of the molten salt in the absence of dissolved Ca, and the generated Ca causes the alloy electrode (cathode) to be generated. Ca is replenished to the molten salt on the anti-anode side (that is, the used molten salt sent from the reduction process).

[0046] In this way, replenishment of molten Ca to the molten salt is performed while preventing a decrease in current efficiency in the electrolysis step due to remaining unreacted dissolved Ca. The reason why absorption of Ca occurs on the anode side of the alloy electrode and release of Ca on the anti-anode side is considered as follows.

[0047] Ca is generated at the interface between the alloy electrode and the molten salt on the anode side, but there is a potential on the anode side (a potential difference occurs at the interface), so that the generated metal Ca is transferred to the alloy electrode as the cathode. It is captured. As a result, the Ca concentration in the alloy electrode increases. On the other hand, since there is no potential at the interface between the alloy electrode and the molten salt on the anti-anode side, Ca is dissolved into the molten salt due to the difference in Ca concentration between the alloy electrode and the molten salt. Since the Ca concentration in the molten salt on the anti-anode side is reduced by the reduction reaction, Ca can be dissolved in the molten salt. The same is true for the molten Ca alloy electrode used in the third manufacturing method described later.

[0048] On the anode side, the molten salt decreases with the electrolysis. To compensate for this, the molten salt that does not contain dissolved Ca may be newly replenished, or a part of the molten salt that is supplied with the power of the reduction process. May be used cyclically. Reduction process power If only a part of the molten salt sent is used, dissolved Ca to be mixed in is small, and knock reaction can be suppressed to a level that does not cause any problem.

[0049] As the Ca alloy constituting the molten Ca alloy electrode, an Mg-Ca alloy, an A1-Ca alloy, a Zn-Ca alloy or the like is desirable. The melting point of these Ca alloys is relatively low, 500 ° C or higher for Mg-Ca alloy, 600 ° C or higher for A1-Ca alloy, and 420 ° C or higher for Zn-Ca alloy. In order to ensure such a low melting point, the Ca concentration is particularly preferably 45% or less for a Mg—Ca alloy, more preferably 15% or less. 20% or less is desirable for A1-Ca alloy. Also, in the case of Zn—Ca alloy, it is desirable that the content be 40% or less, and more preferably 20% or less. On the other hand, the lower limit of the Ca concentration is desirably 0.5%. The greater the difference between the Ca concentration of the molten salt on the anti-anode side and the Ca concentration of the molten Ca alloy, the greater the ability to increase the Ca elution rate into the molten salt.

[0050] It is not always impossible to use a Pb-Ca alloy or a Sn-Ca alloy, but there is a disadvantage that the melting point is too low.

[0051] The use of a molten alloy electrode as a cathode in the electrolysis of CaCl is disclosed in US Pat.

2

No. 92096. The electrolysis of CaCl here is Ca conversion

2

It is used for the original production of FeZNd, and has no circulation of CaCl.

2

The two points are clearly different from the use of the molten alloy electrode in the first to third production methods.

[0052] In the above-described first or second production method, as a means for supplementing Ca in the molten salt consumed in the reduction reaction, a molten salt whose Ca concentration is increased by electrolysis of the molten salt is circulated and used. However, in this method, it is necessary to circulate a large amount of the molten salt between the reaction vessel and the electrolytic cell, and the equipment becomes large.

Therefore, in the third production method, a molten Ca alloy electrode is used as a cathode in the electrolysis step, and this is used as a Ca transfer medium. That is, in the second production method, Ca generated on the cathode side is dissolved in a molten Ca alloy constituting an electrode, and the Ca is converted from the molten Ca alloy into a used molten salt introduced into the reaction vessel by the reaction vessel. The Ca is recirculated and used by increasing the Ca concentration of the molten salt by leaching and circulating it. On the other hand, in the third production method, the molten Ca alloy with increased Ca content is transferred to the reaction vessel, and the molten salt containing CaCl To dissolve Ca in the molten salt to recycle Ca.

[0054] In the third production method, an electrolytic cell is required for performing a Ca generation step by electrolysis (that is, performing an operation in the Ca generation step), and Ti is generated by a reduction reaction. A reaction vessel is required to perform the operation in the production process, but the electrolytic cell and the reaction vessel can be shared by one vessel (or vessel).

When the electrolytic cell and the reaction vessel are used separately, for example, a molten salt containing CaCl

2

And holding it in the reaction vessel, performing the operation in the Ca generation step by electrolysis in the electrolysis tank, transferring the molten Ca alloy from the electrolysis tank to the reaction vessel, and replenishing the Ca and Ti generation steps in the reaction vessel. Then, the molten Ca alloy with Ca consumed in the tank is sent back to the electrolytic cell.

[0056] In this case, a temperature difference can be imparted to the molten salt between the electrolytic cell and the reaction vessel. This has the following advantages. For example, the temperature of the molten salt in the electrolytic cell is lower than the temperature of the molten salt in the reaction vessel. That is, a combination of high-temperature reduction and low-temperature electrolysis. In this case, the reactivity of Ca is increased by the high-temperature reduction, the production efficiency of Ti or Ti alloy is improved, and the solubility of Ca in the molten salt is reduced by low-temperature electrolysis, and the transfer of Ca from the molten salt to the molten Ca alloy Is promoted.

When the electrolytic cell and the reaction vessel are shared by one vessel (or vessel), for example, the molten salt containing CaCl is held in the reaction vessel also serving as the electrolytic vessel, and the molten salt in the reaction vessel, This solution

2

The interface between the molten salt and the molten Ca alloy constituting the cathode is separated into an anode side and an anti-anode side by a partition wall, and electrolysis is performed. In the vicinity of the anode, C1 gas is generated, and the cathode (molten Ca alloy),

2

Ca is generated in the vicinity of the cathode separated on the anode side by the partition (Ca generation step). This Ca is taken into the molten Ca alloy. On the other hand, on the anti-anode side, a Ca replenishment process in which Ca dissolves from the molten Ca alloy into the molten salt proceeds.

[0058] In this case, it is difficult to apply a temperature difference to the molten salt between the electrolytic tank and the reaction vessel, but the structure of the tank (or the vessel) is simplified, and facilities and cost for transporting the molten Ca alloy are also reduced. No longer needed.

[0059] The handling of the Ti particles or Ti alloy particles generated in the molten salt is as described above, and the third production method also includes a Ti separation step of separating the generated Ti or Ti alloy from the molten salt. Embodiments can be employed.

[0060] Regarding the handling of molten salt separated from Ti or Ti alloy powder, it is reasonable and economical to introduce this into the Ca generation step by electrolysis and the Z generation step by Z or reduction reaction. It is.

[0061] Further, the molten salt separated from Ti or Ti alloy in the Ti separation step is reacted with the molten Ca alloy in which Ca has been consumed in the Ti generation step, and the unreacted Ca in the molten salt causes the molten Ca It is possible to increase the Ca in the alloy and use the molten Ca alloy in the Ca replenishment process. In this way, Ca in the molten Ca alloy can be supplemented without using electrolysis.

[0062] Further, by reacting the Ca with the consumed molten Ca alloy, unreacted Ca in Ti or the molten salt separated from the Ti alloy can be removed. Thereby, when the molten salt separated from Ti or Ti alloy is introduced into the Ca generation step by electrolysis, back reaction can be prevented, which is advantageous.

[0063] Replenishment of Ca is also preferably performed at a low temperature without using this electrolysis. At low temperatures, the solubility of Ca in the molten salt decreases, the efficiency of removing unreacted Ca increases, and the transfer of Ca into the molten Ca alloy is promoted, and the Ca in the molten Ca alloy tends to increase .

In the first to third production methods, CaCl having a melting point of 780 ° C. is used as a molten salt.

2

With NaCl, KC1, CaF

2 Mixed molten salts may be used. The use of a mixed molten salt lowers the melting point and lowers the temperature of the molten salt, which increases the durability of the furnace material, prolongs the life of the furnace material, and reduces the evaporation of Ca and salts from the liquid surface. Is suppressed. For example, if a mixed salt with NaCl is used, the melting point of the molten salt can be lowered to about 500 ° C.

[0065] The advantage in terms of the furnace material by lowering the temperature of the molten salt can be obtained in all steps including the reduction step and the electrolysis step. In the electrolysis process, the temperature of the molten salt is lowered, so that the solubility of Ca is lowered, and the convection and diffusion of the molten salt are suppressed, and the back reaction of Ca is also suppressed. If importance is placed on the reactivity in the reduction step, raise the temperature of the molten salt in the reduction step!

In the first production method, an embodiment in which a molten Ca solution is held on a molten salt in a reaction vessel may be adopted. In this case, the temperature of the molten salt is set to the melting point of Ca (838 ° C.). C) It cannot be reduced below. However, other alkaline earth metals and alkali metals are mixed with Ca By doing so, the melting point can be lowered. For example, by mixing Ca with Mg, the melting point can be lowered to 516 ° C. Force and the mixture force of Ca and Mg

(2) Since only Ca dissolves in the molten salt and Mg hardly dissolves, the reduction reaction of TiCl by Ca dissolved in CaCl should proceed even when using molten metal with Mg added to Ca.

twenty four

Can do.

[0067] In the first to third production methods, TiCl is basically used as a raw material of Ti.

4 Ti alloy can be manufactured by mixing TiCl with other metal chlorides.

Four

Noh. Both TiCl and other metal chlorides are reduced by Ca at the same time.

Four

Thus, Ti alloy grains can be produced. It should be noted that the metal salted slag here may be used in the form of gas, liquid, or misaligned.

[0068] Regarding the size of the Ti or Ti alloy to be produced, it is preferable that the average particle size is 0.5 to 50 µm. Because, after these grains are formed in the molten salt, the grains are removed by the molten salt force, but if they are not small enough to flow together with the molten salt, the removal becomes difficult . Therefore, an appropriate size is 50 m or less. In addition, the reason why the appropriate minimum diameter is set to 0.5 m is a force that makes it possible to remove even smaller objects, and that makes it difficult to separate from molten salt.

[0069] Regarding the handling of CaCl extracted out of the reaction vessel, as described above,

2

electrolyzes into a and C1 and converts the Ca generated by electrolysis into Ti in the reaction vessel

2

Used for On the other hand, C1 generated by electrolysis is reacted with TiO

twenty two

It is desirable to generate TiCl and use it for the Ti generation reaction in the reaction vessel.

Four

[0070] By configuring such a cycle, Ca that is expensive if purchased can be used repeatedly as a reducing agent many times, the production cost of TiCl can be kept low, and the production cost of Ti or Ti alloy can be reduced.

Four

The strike can be reduced.

[0071] It should be noted here that Ca generated in the force electrolysis process mentioned above is converted from CaCl.

2 Reduction of Ca production cost due to the elimination of strict separation. One of the reasons why Ca has been used for industrial production of metal Ti is that separation of Ca and CaCl is difficult.

2

That is what. That is, Mg is produced by electrolysis of MgCl, but Mg is Mg

2

Since it hardly dissolves in C1, the generated Mg is efficiently recovered. Na is also the electric component of NaCl By the solution, it can be produced efficiently as in the case of Mg. On the other hand, Ca is produced by CaCl electrolysis.

2

The generated Ca dissolves in CaCl, making it difficult to produce only Ca efficiently.

2

Also, the phenomenon that dissolved Ca returns to CaCl by back reaction is added. Therefore, manufacturing efficiency

2

In the electrolytic production of Ca, techniques such as increasing the recovery rate of Ca by devising the electrode etc. are also used. The cost of producing Ca is still high.

[0072] However, in the first to third production methods, a molten salt in which Ca is dissolved is positively used, so if caution is taken in knocking reaction, the molten salt is mixed with Ca in the electrolysis step. No problem It is not necessary to completely separate only Ca. That is, Ca may be introduced into the reaction vessel from the electrolytic bath together with the molten salt or contained in the molten Ca alloy. Therefore, the cost of electrolytic production of Ca can be significantly reduced.

Brief Description of Drawings

FIG. 1 is a diagram illustrating a configuration of a metal Ti manufacturing apparatus showing a first embodiment of a first manufacturing method.

FIG. 2 is a diagram illustrating a configuration of a metal Ti manufacturing apparatus showing a second embodiment of the first manufacturing method.

FIG. 3 is a diagram illustrating a configuration of a metal Ti manufacturing apparatus showing a third embodiment of the first manufacturing method.

FIG. 4 is a diagram illustrating a configuration of a metal Ti manufacturing apparatus showing a first embodiment of the second manufacturing method.

FIG. 5 is a diagram illustrating a configuration of a metal Ti manufacturing apparatus showing a second embodiment of the second manufacturing method.

FIG. 6 is a view for explaining the configuration of a metal Ti manufacturing apparatus showing a third embodiment of the second manufacturing method.

FIG. 7 is a diagram illustrating a configuration of a metal Ti manufacturing apparatus showing a first embodiment of the third manufacturing method.

FIG. 8 is a diagram illustrating a configuration of a metal Ti manufacturing apparatus showing a second embodiment of the third manufacturing method. FIG. 9 is a view for explaining the configuration of a metal Ti manufacturing apparatus showing a third embodiment of the third manufacturing method.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the first to third manufacturing methods will be described with reference to the drawings.

1. About the first manufacturing method

FIG. 1 is a view for explaining a configuration of a metal Ti manufacturing apparatus showing a first embodiment of a first manufacturing method.

[0075] In the first embodiment of the first manufacturing method, a cylindrical reaction vessel 1 is used. Reaction vessel 1 is an iron closed vessel. At the ceiling of the reaction vessel 1, a reducing agent supply pipe 2 for supplying Ca as a reducing agent is provided. The bottom of the reaction vessel 1 has a tapered shape whose diameter is gradually reduced downward to promote the discharge of the generated Ti particles, and the generated Ti particles are discharged to the center of the lower end. A Ti discharge pipe 3 is provided.

On the other hand, inside the reaction vessel 1, a cylindrical separation wall 4 containing heat exchange is disposed with a predetermined gap between the separation wall 4 and the inner surface of the same part in a straight month. At the upper part of the reaction vessel 1, a molten salt discharge pipe 5 for discharging CaCl in the vessel to the side is provided.

2

The raw material supply pipe 6 for supplying TiCl through the separation wall 4 reaches the center of the container.

Four

It is provided through.

[0077] In operation, a molten CaCl solution in which Ca is dissolved is held as a molten salt in the reaction vessel 1.

2

The The liquid level is set to a level higher than the molten salt discharge pipe 5 and lower than the upper end of the separation wall 4. Inside the separation wall 4, the molten Ca

2

Is held.

Then, in this state, the molten CaCl solution inside the separation wall 4 is

2

TiCl gas is supplied as a metal chloride containing C1. As a result, the inside of the separation wall 4

4 4

Side, the TiCl is reduced by Ca in the molten CaCl solution,

2 4 2

Of metal Ti is produced.

[0079] The TiCl gas supplied into the molten CaCl solution becomes a large number of bubbles, and the molten CaCl

The reaction efficiency is increased by ascending in the solution and promoting stirring with the molten CaCl solution.

2

[0080] The Ti particles generated in the molten CaCl solution inside the separation wall 4 in the reaction vessel 1 Settles inside and accumulates on the bottom of the container. The deposited Ti particles are appropriately extracted downward together with the molten CaC 1 liquid from the Ti discharge pipe 3 and sent to the separation step 7.

2

[0081] The molten CaCl solution having consumed Ca by the reduction reaction inside the separation wall 4

2

It rises outside the separation wall 4 via the lower part and is discharged from the molten salt discharge pipe 5. The discharged molten CaCl solution is sent to the electrolysis step 8.

2

[0082] Inside the separation wall 4, the molten CaCl 2 retained on the molten CaCl

22 Ca is dissolved in solution 2 and replenished. At the same time, the solution is returned to the molten sea CaCl solution inside the separation wall 4.

Ca is replenished from the two-agent supply pipe 2.

[0083] In this way, metal Ti is continuously produced in reaction vessel 1. Inside the separation wall 4, a molten CaCl solution in which Ca is dissolved is used, and the reduction reaction is performed by Ca in the molten CaCl solution.

twenty two

As a result, the reaction field spreads almost completely inside the separation wall 4 and the TiCl supply rate increases.

Four

Will be possible. As described above, high-purity Ti grains are produced with high efficiency for various reasons including this.

[0084] Here, the separation wall 4 is made of a molten CaCl solution containing a large amount of Ca before being used for the reduction of TiCl,

4 2 Mixing with molten CaCl solution containing almost no Ca after use increases the reaction efficiency.

2

On the other hand, in the separation step 7, the Ti particles extracted from the reaction vessel 1 together with the molten CaCl solution are dissolved.

2

Separated from molten CaCl solution. Specifically, the Ti particles are compressed to squeeze out the molten CaCl solution.

2 2 Further, the Ti particles are washed. The molten CaCl solution obtained in separation step 7

2

It is sent to the electrolysis step 8 together with the extracted molten CaCl solution.

2

[0086] In the electrolysis step 8, the molten CaCl solution introduced from the reaction vessel 1 and the separation step 7 is converted into electricity.

2 Separation into Ca and C1 gas by decomposition. Ca is returned into the reaction vessel 1. Where Ca is C

2

aCl power No need for complete separation No problem if returned to reaction vessel 1 with CaCl

twenty two

. This is because CaCl in which Ca is dissolved is used in the reaction vessel 1. The contents of this separation operation

2

The easiness reduces the electrolytic production cost of Ca.

[0087] The C1 gas generated in the electrolysis step 8 is sent to the salting step 9. Here, TiO

2 2 process produces TiCl. Also, by using carbon powder together,

Four

Oxygen is released in the form of CO. The produced TiCl is reacted in

twenty four

Introduced into vessel 1. In this way, the circulation of CaCl allows the reducing agents Ca and C1 The gas is cycled. In other words, metal Ti is continuously supplied only by replenishment of TiO and C.

2

It is manufactured in.

FIG. 2 is a configuration diagram of a metal Ti manufacturing apparatus showing a second embodiment of the first manufacturing method. The second embodiment of the first manufacturing method differs from the first embodiment in that a reducing agent supply pipe 2a is provided at the lower part of the reaction vessel 1 and Ca is supplied from the lower part to the inside of the separation wall 4. I do.

[0089] In the second embodiment, the molten Ca liquid force as the reducing agent is determined by the specific gravity difference from the molten CaCl solution.

2

The inside of the separation wall 4 rises from bottom to top. Because Ca dissolves in CaCl during this floating process

2

, Ca dissolution efficiency increases. The floated molten Ca accumulates on the molten CaCl solution and

2

Dissolve Ca in molten CaCl solution.

2

FIG. 3 is a configuration diagram of a metal Ti manufacturing apparatus showing a third embodiment of the first manufacturing method. In the third embodiment, the position of the raw material supply pipe 6a is different. That is, in the first or second embodiment, the raw material supply pipe 6 is configured to supply TiCl to the center of the container.

Four

In the embodiment, the configuration is such that TiCl is supplied to a position deviated from the center inside the separation wall 4.

Four

ing. According to this configuration, the convection due to the gas lift of the TiCl gas is melted inside the separation wall 4.

Four

Occurs in CaCl solution. This convection of CaCl promotes the dissolution of Ca in CaCl,

2 2 2

Increases efficiency.

[0091] 2. Regarding the second manufacturing method

FIG. 4 is a configuration diagram of a metal Ti manufacturing apparatus showing a first embodiment of the second manufacturing method.

[0092] In the first embodiment of the second production method, a reaction vessel 1 for performing a reduction step and an electrolytic cell 10 for performing an electrolysis step are used. The reaction vessel 1 holds Ca-rich molten CaCl in which Ca is dissolved in a relatively large amount as a molten salt. CaCl has a melting point of about 780 ° C, and its molten salt is

twenty two

It is heated above its melting point.

[0093] In the reaction vessel 1, the raw material supply pipe 6 is used to convert gaseous TiCl into molten salt in the reaction vessel 1.

4 is dispersed and injected, and this is reduced by dissolved Ca in the molten salt to form particulate metal Ti. The generated Ti particles sequentially accumulate at the bottom of the reaction vessel 1 due to a difference in specific gravity.

[0094] The Ti particles collected at the bottom of the reaction vessel 1 are extracted from the reaction vessel 1 together with the molten salt present at the bottom, and sent to the Ti separation step 7. In the Ti separation step 7, the Ti particles extracted together with the molten salt from the reaction vessel 1 are separated by molten salt. Specifically, compress the Ti grains Squeeze out the molten salt. The Ti particles obtained in the Ti separation step 7 are dissolved to form a Ti ingot.

[0095] On the other hand, the molten salt separated by Ti particle force in the Ti separation step 7 is a used molten salt, which consumes Ca and decreases the Ca concentration. The molten salt is sent from the reaction vessel 1 to the electrolytic cell 10.

[0096] In the electrolytic cell 10, molten CaCl as a molten salt is electrolyzed between the anode 11 and the cathode 12.

2

Then, C1 gas is generated on the anode 11 side, and Ca is generated on the cathode 12 side. Where the cathode 12

2

Is a molten Ca alloy electrode 14, which is a heat-resistant container 13 with an open bottom inserted into the molten salt in the electrolytic cell 10, a molten Ca alloy 14 contained in the heat-resistant container 13, and a top plate of the heat-resistant container 13. An electrode rod 15 penetrated and inserted into the molten Ca alloy 14 and a partition wall 16 for partitioning the molten salt in the electrolytic cell 10 into an anode side and an anti-anode side are provided.

[0097] The molten Ca alloy 14 has a lower specific gravity than the molten salt here, for example, an Mg-Ca liquid or the like.

The heat-resistant and insulating partition wall 16 is located directly below the cathode 12 and divides the molten salt in the electrolytic cell 10 into an anode side and an anti-anode side together with an interface between the molten Ca alloy 14 and the molten salt. The part is inserted into the molten Ca alloy 14, and the lower end is in close contact with the bottom plate of the electrolytic cell 10.

[0098] The molten salt sent from the reaction vessel 1 to the electrolytic cell 10 directly or via the Ti separation step 7 is introduced into the electrolytic cell 10 on the side opposite to the anode. The molten salt on the anode side is molten CaCl containing substantially no dissolved Ca. The molten salt on the anode side transfers electricity between anode 11 and cathode 12.

2

It is decomposed and generates C1 gas on the side of the anode 11 and generates Ca on the side of the cathode 12. Cathode 12

2

The Ca generated on the side melts into the molten Ca alloy.

[0099] On the other hand, the molten salt on the anti-anode side is a used molten salt introduced from the reaction vessel 1, and although dissolved Ca is consumed, unreacted dissolved Ca is included. Ca melts out of the molten Ca alloy 14 into this molten salt. As a result, dissolved Ca is replenished to the used molten salt introduced from the reaction vessel 1, and the Ca-rich molten salt is introduced into the reaction vessel 1 through the reducing agent supply pipe 2 to generate Ti particles by Ca reduction. Used for circulation.

[0100] On the other hand, the C1 gas generated near the surface of the anode 11 is sent to the salting step 9. Chlorination process 9

2

Then, TiCl, which is a raw material of Ti, is generated by performing a salting treatment on TiO. Generated

twenty four

TiCl is introduced into the reaction vessel 1 through the raw material supply pipe 6, and Ti particles are generated by Ca reduction.

Four

Used for circulation. [0101] As described above, in the first embodiment of the second production method, the molten salt (molten CaCl 2 in which Ca is dissolved) is subjected to the reduction step (reaction vessel 1), the separation step 7, and the electrolysis step (electrolysis tank 10). Circulate and reduce

2

By repeating the operation of replenishing Ca consumed in the step (reaction vessel 1) in the electrolysis step (electrolysis tank 10), production of Ti is continued in the reduction step (reaction vessel 1). In other words, high-quality Ti grains are continuously produced by Ca reduction simply by manipulating the Ca concentration in the molten salt without performing supplementation and removal of solid Ca.

[0102] In order to replenish Ca, the used molten salt containing unreacted dissolved Ca is introduced into the electrolysis step, and the unreacted dissolved Ca is removed from the non- Since it is introduced on the anti-anode side, which is the region, and is not directly involved in electrolysis, back reaction due to dissolved Ca is prevented. Therefore, the current efficiency in the electrolysis process increases. On the anode side, which is an electrolysis area in the electrolysis tank 10, molten CaCl is consumed as electrolysis proceeds. Make up for this

2

For this purpose, molten CaCl containing substantially no dissolved Ca is externally supplemented. Or, that

2

A small amount of spent molten salt is introduced into the anode side separately from or together with the replenishment (according to the route shown by the broken line in FIG. 4).

[0103] The temperature of the molten salt is higher than the melting point of CaCl (about 780 ° C) in any process.

2

Is managed.

FIG. 5 is a configuration diagram of a metal Ti manufacturing apparatus showing a second embodiment of the second manufacturing method.

[0105] In the second embodiment, the structure of the reaction vessel 1 is specifically shown. The reaction vessel 1 used here is a cylindrical closed vessel made of iron. At the ceiling of the reaction vessel 1, a reducing agent supply pipe 2 for supplying Ca as a reducing agent is provided. The bottom of the reaction vessel 1 has a tapered shape whose diameter is gradually reduced downward in order to promote the discharge of the generated Ti particles. A discharge pipe 3 is provided.

[0106] On the other hand, inside the reaction vessel 1, a cylindrical separation wall 4 containing heat exchange is arranged with a predetermined gap between the separation wall 4 and the inner surface of the same part. At the upper part of the reaction vessel 1, a molten salt discharge pipe 5 for discharging CaCl in the vessel to the side is provided.

2

The raw material supply pipe 6 for supplying the TiCl

Four

It is provided through. [0107] In the operation, a molten CaCl solution in which Ca is dissolved, for example, as a molten salt is placed in the reaction vessel 1.

2 Retained. The liquid level is set to a level higher than the molten salt discharge pipe 5 and lower than the upper end of the separation wall 4.

Then, in this state, the molten CaCl solution inside the separation wall 4

2

4 4

The TiCl is reduced by Ca in the molten CaCl solution,

2 4 2

Of metal Ti is produced.

[0109] The TiCl gas supplied into the molten CaCl solution becomes a large number of bubbles, and the molten CaCl

2

[0110] The Ti particles generated in the molten CaCl solution inside the separation wall 4 in the reaction vessel 1

2

Settles inside and accumulates on the bottom of the container. The deposited Ti particles are melted from the Ti discharge pipe 3

It is withdrawn with the two liquids and sent to the Ti separation step 7.

[0111] The molten CaCl that consumed Ca by the reduction reaction inside the separation wall 4

2

And rises outside the separation wall 4 via the other side and is discharged from the molten salt discharge pipe 5. The discharged molten CaCl solution is sent to the electrolysis step 8.

2

[0112] In this way, metal Ti is continuously produced in reaction vessel 1. Inside the separation wall 4, a molten CaCl solution in which Ca is dissolved is used, and the reduction reaction is performed by Ca in the molten CaCl solution.

twenty two

Four

[0113] Here, the separation wall 4 is made of a molten CaCl solution containing a large amount of Ca before being used for the reduction of TiCl,

2

On the other hand, in the separation step 7, Ti particles extracted from the reaction vessel 1 together with the molten CaCl solution are dissolved.

2

2 2 The molten CaCl solution obtained in the separation step 7 is the molten CaCl

22 The solution is sent to the electrolysis step 8 together with the solution.

[0115] In the electrolysis step 8, as described above, the molten CaCl liquid introduced from the reaction vessel 1 and the separation step 7 is separated into Ca and C1 gas by electrolysis using the molten Ca alloy electrode as a cathode. The Ca is returned into the reaction vessel 1 through the reducing agent supply pipe 2. Where Ca is from CaCl

2 It is not necessary to completely separate. There is no problem if it is returned to the reaction vessel 1 together with CaCl. Reaction volume

2

This is because CaCl in which Ca is dissolved is used in the vessel 1. This ease of separation operation

2

, Ca electrolytic production cost is reduced.

[0116] The C1 gas generated in the electrolysis step 8 is sent to the salting step 9. In the chlorination process 9, TiO

By performing the chlorination treatment, TiCl is produced. Also, by using carbon powder together

Four

The by-product oxygen is emitted in the form of CO. The produced TiCl is supplied through the raw material supply pipe 6.

twenty four

It is introduced into the reaction vessel 1. In this way, the circulation of the molten CaCl

2

Ca and C1 gases are cycled. In other words, only by replenishment of TiO and C

twenty two

Ti is produced continuously.

FIG. 6 is a configuration diagram of a metal Ti manufacturing apparatus showing a third embodiment of the second manufacturing method.

[0118] In the third embodiment, the position of the raw material supply pipe 6a is different from that in the second embodiment.

That is, in the second embodiment, the raw material supply pipe 6 supplies TiCl to the center of the container.

Four

However, in the third embodiment, TiCl is placed at a position where the central force inside the separation wall 4 is biased.

4 It is configured to supply.

[0119] According to this configuration, the convection due to the gas lift of TiCl gas is

4 Produced in liquid 2. This convection of CaCl increases the reduction efficiency.

2

[0120] As described above, the temperature of the molten salt can be reduced by using the mixed molten salt also in the embodiment of V and deviation.

[0121] 3. Regarding the third manufacturing method

FIG. 7 is a configuration diagram of a metal Ti manufacturing apparatus showing a first embodiment of the third manufacturing method.

[0122] In the first embodiment of the third production method, a reaction vessel 1 for performing a Ti generation step by a reduction reaction and an electrolytic cell 10 for performing a Ca replenishment step by electrolysis are used. The reaction vessel 1 holds Ca-rich molten CaCl in which Ca is dissolved in a relatively large amount as a molten salt. CaCl

22 has a melting point of about 780 ° C, and its molten salt is heated above its melting point.

[0123] The inside of the reaction vessel 1 is divided into two parts except for a bottom part by a heat-resistant partition wall 17, one of which is a reduction chamber 18, and the other of which is a molten Ca alloy, which will be described later, is brought into contact with a molten salt to form a molten salt. This is the Ca replenishing chamber 19 where Ca is dissolved in the molten salt. Both chambers communicate at the lower part of the reaction vessel 1, Guarantee the free flow of molten salt.

[0124] In the reduction chamber 18, gaseous TiCl is dispersed and injected into the molten salt in the reaction vessel 1.

Four

As a result, this is reduced by dissolved Ca in the molten salt, and particulate metal Ti is generated. The generated Ti particles sequentially accumulate at the bottom of the reduction chamber 18 due to a difference in specific gravity.

[0125] The Ti particles collected at the bottom of the reduction chamber 18 are extracted from the reduction chamber 18 together with the molten salt present at the bottom, and sent to the Ti separation step 7. In the Ti separation step 7, the Ti particles extracted together with the molten salt from the reduction chamber 18 are separated by molten salt power. Specifically, the Ti particles are compressed to squeeze out the molten salt. The Ti particles obtained in the Ti separation step 7 are dissolved to form a Ti ingot.

[0126] On the other hand, the molten salt that has been subjected to Ti particle separation in the Ti separation step 7 is a used molten salt, Ca is consumed, and the Ca concentration is reduced. This molten salt is sent to the above-mentioned electrolytic cell 10.

[0127] The electrolytic cell 10 contains molten CaCl as a molten salt, and the molten CaCl is

twenty two

Electrolyze at cathode 12. As a result, C1 gas is generated on the side of the anode 11 and

2

On the side, Ca is generated.

[0128] Here, the cathode 12 is a molten Ca alloy electrode. Specifically, the cathode 12 is an insulating heat-resistant container 13 that is inserted into the molten salt in the electrolytic bath 10 and has an open bottom, and is housed in the heat-resistant container 13. The molten Ca alloy 14 and the electrode rod 15 inserted through the top plate of the heat-resistant container 13 and inserted into the molten Ca alloy 14 are provided. The Ca generated on the side of the cathode 12 is taken into the molten Ca alloy 14 in the heat-resistant container 13 in the form of an alloy or solid solution. Thereby, the Ca concentration of the molten Ca alloy 14 in the heat-resistant container 13 increases.

[0129] When the Ca concentration of the molten Ca alloy 14 in the heat-resistant container 13 reaches a predetermined concentration (for example, 15%), the molten Ca alloy 14 having the high Ca concentration is transferred to the Ca in the reaction container 1 by the first transport pipe 20. Inject into refill chamber 19 from above.

[0130] At this time, the molten Ca alloy 14 'injected previously floats on the molten salt in the Ca replenishing chamber 19. This molten Ca alloy 14 ^ has a high Ca concentration at the time of injection, and has a low Ca concentration (for example, several%) by releasing and dissolving Ca in a molten salt below. Therefore, in parallel with the transport of the molten Ca alloy 14 having a high Ca concentration from the inside of the heat-resistant container 13 to the Ca replenishing chamber 19, the used molten Ca alloy having a low Ca concentration that floats on the molten salt in the Ca replenishing chamber 19 14 ′ is transported into the heat-resistant container 13 by the second transport pipe 21. [0131] Thus, in the Ca replenishing chamber 19, the melting and replenishment of Ca from the molten Ca alloy 14 to the molten salt below is continued. As a result, Ca consumed in the production of Ti particles in the reduction chamber 18 is supplemented, and the production reaction is continued.

[0132] On the other hand, the C1 gas generated near the surface of the anode 11 is sent to the salting step 9. Chlorination process 9

2

In the, the chlorination of TiO and C produces TiCl, which is the raw material for Ti.

At the same time, CO gas is also emitted. The generated TiCl is supplied to the reactor 1

twenty four

And recycled to produce Ti particles by Ca reduction.

As described above, in the first embodiment of the third production method, Ca in the molten salt is consumed by the Ca reduction reaction in the reaction vessel 1, and the Ca is melted in the electrolytic cell 10. It is produced by electrolysis of salt and is recycled to produce Ti particles by reduction. In addition, it is not necessary to circulate the molten salt between the reaction vessel 1 and the electrolytic cell 10 when circulating Ca. The molten Ca alloy 14 is used as the cathode in the electrolytic cell 10, and Ca is supplied to the molten salt in the reaction vessel 1 simply by reciprocating between the reaction vessel 1 and the electrolytic cell 10 using this as a Ca transfer medium. And Ti production continues.

[0134] Accordingly, high-quality Ti particles are continuously produced by Ca reduction extremely easily without replenishing or removing solid Ca and without circulating a large amount of molten salt. Note that the temperature of the molten salt is higher than the melting point of CaCl (about

2

E ί 800-850 ° C) [This is managed! /

FIG. 8 is a configuration diagram of a metal Ti manufacturing apparatus showing a second embodiment of the third manufacturing method. The second embodiment differs from the first embodiment in the following points.

[0136] As the molten salt, a multi-component molten salt having a low melting point obtained by mixing CaCl and another salted product is used. Ti

2

Before the molten salt separated from the Ti particles in the separation step 7 is introduced into the electrolytic cell 10, the molten salt is introduced into the Ca removing tank 22. If the melting point of the molten salt is, for example, about 650 ° C., the reaction vessel 1 performs a high-temperature operation in which the temperature of the molten salt is increased to about 850 ° C. On the other hand, in the electrolytic cell 10 and the Ca removing tank 22, low-temperature operation is performed with the temperature of the molten salt lowered to about 700 ° C.

[0137] Performing high-temperature operation (high-temperature reduction) in the reaction vessel 1 increases the reactivity of Ca, and makes it possible to compensate for the decrease in reactivity caused by the decrease in the Ca content ratio in the molten salt. Become. On the other hand, the low-temperature operation in the electrolytic cell 10 and the Ca removal tank 22 Unreacted Ca in the molten salt is removed in advance, and back reaction due to unreacted Ca and a decrease in current efficiency due to this are suppressed.

[0138] That is, the molten salt sent from the reaction vessel 1 to the electrolytic cell 10 through the Ti separation step 7 is used molten salt, and although dissolved Ca is consumed, unreacted Contains dissolved Ca. If unreacted Ca enters the electrolysis process, C1 gas generated on the anode 11 side

2 Reacts and returns to CaCl, a so-called back reaction, which consumes electrolytic current.

2

Current efficiency is reduced.

[0139] In the Ca removal tank 22, the molten salt (containing unreacted Ca) introduced from the Ti separation step 7 is transported from the Ca replenishment chamber 19 in the reaction vessel 1 to the heat-resistant vessel 13 in the electrolysis vessel 10. It is mixed with a part of the used low Ca concentration molten Ca alloy 14 '(indicated as Mg in Fig. 9). As a result, the unreacted Ca in the molten salt is taken into the molten Ca alloy 14 ′ having a low Ca concentration, the unreacted Ca is removed, and the molten Ca alloy 14 having a high Ca concentration is generated.

[0140] By introducing the molten salt from which unreacted Ca has been removed in this way to the electrolytic cell 10, the molten salt is circulated and used without waste, and the force is also increased by the back reaction due to the unreacted Ca in the molten salt and the current caused by the back reaction. A decrease in efficiency is suppressed. The high Ca concentration molten Ca alloy 14 (indicated as Mg—Ca in FIG. 9) by-produced in the Ca removal tank 22 is introduced into the Ca replenishing chamber 19 in the reaction vessel 1.

[0141] By performing the low-temperature operation in the electrolytic cell 10, the solubility of Ca in the molten salt is reduced, the convection and diffusion of the molten salt are also suppressed, and the back reaction is also suppressed at these point forces. In addition, by performing low-temperature switching in the Ca removal tank 22, Ca solubility is reduced, Ca ^ precipitates, and the precipitated Ca is absorbed by the alloy.

[0142] As described above, in the second embodiment of the third production method, by applying a temperature difference to the molten salt between the reaction vessel 1 and the electrolytic cell 10, the current in the Ca generation step by electrolysis is obtained. Efficiency can be increased.

FIG. 9 is a configuration diagram of a metal Ti manufacturing apparatus showing a third embodiment of the third manufacturing method. The third embodiment differs from the first embodiment and the second embodiment in the following points.

[0144] The reaction vessel 1 also serves as an electrolytic cell, and includes a reduction chamber 23 having a deep bottom and an electrolysis chamber 24 having a shallow bottom. The anode 11 is disposed on the anti-reduction chamber side in the electrolysis chamber 24, The heat vessel 13 is disposed at a boundary between the reduction chamber 23 and the electrolysis chamber 24 so as to straddle both chambers. Then, the molten salt in the reaction vessel 1 is supplied to the anode 16 together with the interface between the molten Ca alloy 14 and the molten salt in the heat-resistant vessel 13 by a partition wall 16 provided at the boundary between the reduction chamber 23 and the electrolysis chamber 24. Side and anti-anode side. In other words, the anode side corresponds to the electrolysis chamber 24 having a shallow bottom, and the anti-anode side corresponds to the reduction chamber 23 having a deep bottom.

[0145] In the operation, on the anti-anode side in the reaction vessel 1, that is, in the reduction chamber 23, TiCl which is a raw material of Ti is supplied.

4 Introduced into the molten salt and reduced by Ca in the molten salt to produce Ti particles. On the other hand, on the anode side in the reaction vessel 1, that is, in the electrolysis chamber 24, Ca is generated by the electrolysis of the molten salt by the anode 11 and the cathode 12. The generated Ca is taken into the molten Ca alloy 14 in the heat-resistant container 13. The Ca taken into the molten Ca alloy 14 is released and melted into the molten salt on the anti-anode side in the reaction vessel 1, that is, in the reduction chamber 23. This replenishes the Ca consumed by the generation of Ti grains.

[0146] The feature of the third embodiment is, firstly, that the reactor structure is simple because the reaction container 1 also serves as an electrolytic cell. Second, the efficiency of operation is increased because the molten Ca alloy 14 is not transported between the electrolytic cell and the reaction vessel. In addition, equipment for carrying out the transportation between the tank and the container is not required, and the equipment is also simplified from this point. However, it is difficult to give a temperature difference to the molten salt in the reduction zone and the electrolysis zone.

[0147] Although not shown, also in the third embodiment of the third manufacturing method, Ca in the molten salt introduced into the electrolytic chamber 24 is removed in advance in the same manner as in the second embodiment. be able to. Industrial potential

[0148] The method for producing Ti or a Ti alloy by the first to third Ca reductions is a method for reducing TiCl.

Four

Since it is a method, high purity metal Ti or Ti alloy can be manufactured. Ca is used as the reducing agent, and in particular, the molten salt containing CaCl and in which Ca is dissolved is held in a reaction vessel,

2

Of Ti particles or Ti alloy in molten CaCl solution by reacting metal chloride containing TiCl with Ca

4 2

Since the grains are generated, the supply rate of TiCl, which is a raw material of Ti, can be increased, and the force is increased.

Four

, A continuous production method is possible. Furthermore, replenishment of expensive metal Ca, handling with strong reactivity However, there is no need for an operation for handling Ca alone.

In addition, according to the second manufacturing method, a decrease in current efficiency due to mixing of unreacted Ca, which is a problem in the electrolysis step, can be effectively suppressed by using a molten Ca alloy electrode. Further, according to the third production method, the molten Ca alloy electrode used in the electrolysis step is used as a Ca transfer medium, so that a powerful circulation of the molten salt is not required.

Therefore, the method for producing Ti or Ti alloy of the present invention can be effectively used as a means for efficiently and economically producing high-purity metal Ti.

Claims

The scope of the claims

[1] A molten salt containing CaCl and in which Ca is dissolved is held in a reaction vessel,

2

Reaction of metal chloride containing TiCl with Ca to produce Ti grains or Ti alloy grains in the molten salt

Four

A reduction step to be performed;

A method for producing Ti or a Ti alloy by Ca reduction, comprising a separation step of separating Ti particles or Ti alloy particles generated in the molten salt from the molten salt.

[2] The molten salt containing CaCl according to claim 1, which is a molten salt containing CaCl and NaCl.

twenty two

Production method of Ti or Ti alloy by reduction of Ca described above.

[3] The metal chloride containing TiCl is a mixed gas containing TiCl and another metal chloride.

4 4

A method for producing Ti or a Ti alloy by Ca reduction according to claim 1.

[4] The production of Ti or a Ti alloy by Ca reduction according to claim 1, wherein the molten metal containing Ca is held on the molten salt in the reaction vessel to supply Ca to the molten salt below the molten metal force. Method.

5. The method according to claim 4, wherein the molten metal containing Ca is a molten metal containing Ca and Mg.

Production method of Ti or Ti alloy by Ca reduction.

[6] The method according to claim 1, wherein CaCl by-produced with the production of Ti or Ti alloy is extracted out of the reaction vessel.

2

2. A method for producing Ti or a Ti alloy by Ca reduction according to the item 1.

[7] including an electrolysis step of electrolyzing CaCl extracted to the outside of the reaction vessel into Ca and C1,

twenty two

7. The method for producing Ti or a Ti alloy by Ca reduction according to claim 6, wherein Ca generated in the electrolysis step is used for a reaction for producing Ti or a Ti alloy in the reaction vessel.

[8] A method for producing Ti or a Ti alloy using a reduction reaction with Ca,

The molten salt containing CaCl and dissolved Ca is held in the reaction vessel,

2

The metal chloride containing TiCl is reacted with Ca to form Ti or Ti alloy in the molten salt.

Four

The reduction process

A circulating electrolysis step of electrolyzing the molten salt used for producing the Ti or Ti alloy and extracted from the reaction vessel, producing and replenishing Ca in the molten salt and returning the molten salt to the reaction vessel; Combination,

In addition, in the electrolysis step, an alloy electrode made of a molten Ca alloy is used as a cathode. Original method of producing Ti or Ti alloy.

[9] In the electrolysis step, an interface between the molten salt in the electrolytic cell and the molten Ca alloy constituting the alloy electrode and the molten salt is partitioned into an anode side and an anti-anode side by a partition wall.

9. The method for producing Ti or a Ti alloy by Ca reduction according to claim 8, wherein the molten salt supplied from the reaction vessel is introduced to the anti-anode side.

[10] including a Ti separation step of separating the generated Ti or Ti alloy from the molten salt inside or outside the reaction vessel,

In the discharging step of extracting the molten salt used for producing Ti or Ti alloy out of the reaction vessel, the Ti or Ti alloy produced in the molten salt is extracted out of the reaction vessel together with the molten salt,

In the Ti separating step, the Ti or Ti alloy is separated from the molten salt drawn out of the reaction vessel,

9. The method for producing Ti or Ti alloy by Ca reduction according to claim 8, wherein in the electrolysis step, the molten salt from which the Ti or Ti alloy has been separated and removed is electrolyzed.

11. The method according to claim 1, wherein in the reduction step, a metal chloride containing TiCl is supplied into the molten salt.

Four

8. The method for producing Ti or a Ti alloy by Ca reduction according to 8.

[12] A method for producing Ti or a Ti alloy using a reduction reaction with Ca,

The molten salt containing CaCl is electrolyzed using the molten Ca alloy as the cathode,

2

A step of generating Ca by electrolysis, which increases the Ca content in the molten Ca alloy,

The molten Ca alloy, whose Ca has been increased by the Ca generation process, is brought into contact with molten salt containing CaCl.

2

A Ca replenishing step of dissolving Ca in the molten salt,

By supplying a metal salt containing TiCl to the molten salt in which Ca is dissolved by the Ca replenishing step,

Four

A method for producing Ti or a Ti alloy by Ca reduction including a step of producing a Ti or a Ti alloy in a molten salt by a reduction reaction.

13. The method for producing Ti or Ti alloy by Ca reduction according to claim 12, comprising a Ti separation step of separating Ti or Ti alloy produced in the molten salt from the molten salt.

[14] The molten salt containing CaCl is held in the electrolytic cell and the reaction vessel,

2

a Perform the production process and transport the molten Ca alloy from the electrolytic cell to the reaction The method for producing Ti or a Ti alloy by Ca reduction according to claim 12, wherein a Ca replenishing step and a Ti generating step are performed in the reactor, and the molten Ca alloy in which Ca has been consumed in the reaction vessel is sent back to the electrolytic cell. .

15. The method for producing Ti or a Ti alloy by Ca reduction according to claim 14, wherein the temperature of the molten salt in the electrolytic cell is lower than the temperature of the molten salt in the reaction vessel.

[16] The molten salt containing CaCl is held in a reaction vessel that also serves as an electrolytic

2

In addition to performing electrolysis using the electrodes, the molten salt in the reaction vessel and the interface between the molten salt and the molten Ca alloy are separated into an anode side and an anti-anode side by partition walls, and a Ca generation step is performed on the anode side. 13. The method for producing Ti or a Ti alloy by Ca reduction according to claim 12, wherein a Ca replenishing step and a Ti generating step are performed on the side opposite to the anode.

[17] The chlorination step 9 of reacting C1 generated in the electrolysis step with TiO to generate TiCl

2 2 4

The TiCl produced in the chlorination process 9 is used for the Ti or Ti alloy formation reaction in the reaction vessel.

Four

13. The method for producing Ti or a Ti alloy by Ca reduction according to claim 7, 8 or 12.

[18] The Ti or Ti alloy by Ca reduction according to claim 1 or 13, wherein the generated Ti or Ti alloy is drawn out of the reaction vessel together with the molten salt, and the Ti or Ti alloy is separated by molten salt force outside the tank. Is the manufacturing method of Ti alloy.

[19] The method according to claim 13, wherein the molten salt separated from Ti or Ti alloy in the Ti separation step is introduced into a Ca generation step by electrolysis and a Z generation step by Z or Ti reduction reaction. Manufacturing method of Ti or Ti alloy.

[20] The molten salt separated from Ti or Ti alloy in the Ti separation step is reacted with the molten Ca alloy in which Ca has been consumed in the Ti generation step, and is melted by unreacted Ca in the molten salt. 14. The method for producing Ti or a Ti alloy by reduction of Ca according to claim 13, wherein Ca in the Ca alloy is increased, and the molten Ca alloy is used in a Ca replenishing step.

[21] The molten salt containing CaCl is, in addition to CaCl, NaCl, KC1, LiCl and CaF

13. The method for producing a Ti or Ti alloy by Ca reduction according to claim 12, which is a multi-component molten salt containing at least one of 222.

[22] The metal chloride containing TiCl is a mixture containing TiCl and another metal chloride.

4 4

A method for producing Ti or a Ti alloy by reducing Ca according to claim 12. 13. The method for producing Ti or Ti alloy according to claim 12, wherein the produced Ti or Ti alloy is a granule having an average particle size of 0.5 to 50 m.