JPH06146049A - Molten salt electrolytic sampling method for high-fusion-point active metal such as titanium - Google Patents
Molten salt electrolytic sampling method for high-fusion-point active metal such as titaniumInfo
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- JPH06146049A JPH06146049A JP29324892A JP29324892A JPH06146049A JP H06146049 A JPH06146049 A JP H06146049A JP 29324892 A JP29324892 A JP 29324892A JP 29324892 A JP29324892 A JP 29324892A JP H06146049 A JPH06146049 A JP H06146049A
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- molten salt
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、チタンや希土類などの
活性で高融点な元素の酸化物を溶融塩浴中で電解還元
し、単一金属あるいはそれらの合金を採取するチタン等
の高融点な活性金属の溶融塩電解採取方法に関するもの
である。BACKGROUND OF THE INVENTION The present invention relates to a high melting point of titanium or the like for collecting a single metal or an alloy thereof by electrolytically reducing an oxide of an active and high melting point element such as titanium or rare earth in a molten salt bath. The present invention relates to a method for electrowinning molten salts of various active metals.
【０００２】[0002]
【従来の技術】金属Tiを製造する工業的な方法には、Ti
O2を塩素化してTiCl4 とした後、これをMgあるいはNaで
還元する金属熱還元法がある。この方法では、還元材と
なるMg、Na等はTiの還元工程とは別に、MgCl2 あるいは
NaClの電解還元により製造する必要がある。2. Description of the Related Art An industrial method for producing metallic Ti is Ti
There is a metal thermal reduction method in which O 2 is chlorinated into TiCl 4 and then this is reduced with Mg or Na. In this method, Mg, Na, etc., which serve as a reducing material, are separated from MgCl 2 or
It must be manufactured by electrolytic reduction of NaCl.
【０００３】このうちMgで還元する方法(Kroll法) を採
用した場合、TiCl4 中の塩素分はMgCl2 として分離され
るが、得られる金属Tiはその内部にMgCl2 や未反応のMg
などが不純物として多量に含まれた状態となっているた
め、真空蒸留や水洗いなどの精製処理が行われるが、こ
のような精製処理後でもかなりの量のMgCl2 が除去しき
れずに残留したスポンジ状Tiが得られる。When the method of reducing with Mg (Kroll method) is adopted, the chlorine content in TiCl 4 is separated as MgCl 2 , but the obtained metallic Ti contains MgCl 2 and unreacted Mg.
Since impurities are contained in large quantities as impurities, purification treatment such as vacuum distillation and water washing is performed.However, even after such purification treatment, a considerable amount of MgCl 2 could not be completely removed and the sponge remained. Form Ti is obtained.
【０００４】一方、金属Naで還元する方法 (Hunter法)
を採用した場合、残留するNaClの除去のために、水洗い
が行われるが、Mg還元の場合と同様に、相当量のNaClが
残留したスポンジ状Tiとなる。On the other hand, a method of reducing with metallic Na (Hunter method)
In the case of adopting, the washing with water is carried out to remove the residual NaCl, but as in the case of the Mg reduction, a spongy Ti having a considerable amount of residual NaCl remains.
【０００５】アルミにおいて実用化されている溶融塩電
解法のチタンへの適用については、多くの研究開発が行
われてきたものの、まだ実用技術としては完成されてい
ない。これは、チタンが活性で高融点な元素なためであ
り、電解法の開発で解決されるべき課題として、(1) 高
温で腐食性の強い電解浴に耐える容器材料技術、(2)固
体で析出するTiの取り出し方法と樹枝状に析出するTiの
間に含まれる溶融塩の分離回収技術 (Tiの固相採取法の
場合) 、(3) 陰極と陽極とを仕切る隔膜技術、などが未
確立なためとされている。Although much research and development has been carried out on the application of the molten salt electrolysis method, which has been put to practical use in aluminum, to titanium, it has not been completed as a practical technique. This is because titanium is an active element with a high melting point, and issues to be solved in the development of the electrolysis method are (1) container material technology that can withstand highly corrosive electrolytic baths at high temperatures, and (2) solid materials. The method of extracting the precipitated Ti and the separation and recovery technology of the molten salt contained in the dendritic Ti (in the case of the solid phase collection method of Ti), (3) the diaphragm technology for partitioning the cathode and the anode, etc. It is supposed to be established.
【０００６】さらに、チタンやチタン合金の線・棒・板
製品を製造する場合は、スポンジ状チタンに残留する塩
化物を除去するため、溶解工程が不可欠であり、通常は
真空アーク溶解法が多用されている。しかしながらこの
溶解法では、溶解に先立って消耗電極を、スポンジTiの
プレス成形や溶接により製造する必要がある。このよう
に、現状のチタン製品の製造工程は、工程が煩雑で生産
性および経済性が低いという問題がある。Further, when manufacturing titanium, titanium alloy wire, rod and plate products, a melting step is indispensable in order to remove chlorides remaining in titanium sponge, and the vacuum arc melting method is usually used frequently. Has been done. However, in this melting method, it is necessary to manufacture the consumable electrode by press molding or welding of sponge Ti before melting. As described above, the current manufacturing process of titanium products has a problem that the process is complicated and productivity and economic efficiency are low.
【０００７】また、La、Ce、Mishメタル、U などのラン
タン系列やアクチニウム系列の元素で、比較的低融点
(1200℃以下) な元素については、CaやMgによる金属熱
還元法とともに、溶融塩電解法も工業的な金属、合金採
取法としてすでに利用されている。溶融塩電解法として
は、塩化物の電解法、フッ化物浴中での酸化物の電解法
など多数の報告がでている。[0007] Further, it is a lanthanum series or actinium series element such as La, Ce, Mish metal, and U, and has a relatively low melting point.
For elements such as (1200 ℃ or less), molten salt electrolysis is already used as an industrial metal and alloy extraction method along with metal thermal reduction method using Ca and Mg. As the molten salt electrolysis method, many reports have been made such as a chloride electrolysis method and an oxide electrolysis method in a fluoride bath.
【０００８】例えば、E.S.Shedd,J.D.Marchant,T.A.Hen
rie:US Bur.Mines Rep.Inv.6882 (1966)、特開昭61-878
88号、D.G.Kesterke,D.H. Fleck,T.A.Henrie:US Bur.Mi
nesRep.Inv.6436 (1964) などがある。For example, ES Shedd, JD Marchant, TAHen
rie: US Bur.Mines Rep.Inv.6882 (1966), JP 61-878
No. 88, DG Kesterke, DH Fleck, TAHenrie: US Bur.Mi
nesRep.Inv.6436 (1964) and so on.
【０００９】これらの溶融塩電解還元方法では、溶融塩
浴を保持する容器として黒鉛あるいはMo、Ta、W 等の高
溶融点金属によるライニング材などを用い、溶融塩浴と
しては目的とする金属のフッ化物（例えば、CeF3、Nd
F3、UF4 など）を、アルカリ金属あるいはアルカリ土類
金属のフッ化物（例えば、CaF2、BaF2、MgF2、LiF な
ど）およびそれらの混合塩で希釈した組成の塩を使用し
ている。しかしながら、これらの溶融塩電解技術が実用
化されているのは、Mishメタルなどの融点の比較的低い
合金・元素で、液相として電解生成金属が捕集できるも
のに限定されており、希土類のなかでも融点の高いGd、
Tbなどには適用されていない。これは、チタンの場合と
同様に、電解析出物を固相で採取する場合には、析出金
属と付着する溶融塩の分離が工業的に問題となり、液相
として捕集するためには、高温の溶融塩浴に耐える電解
槽容器の問題が解決されていないためである。In these molten salt electrolytic reduction methods, graphite or a lining material made of a high melting point metal such as Mo, Ta or W is used as a container for holding the molten salt bath, and the molten salt bath is made of a target metal. Fluoride (eg CeF 3 , Nd
F 3, etc. UF 4 to), fluoride of alkali metal or alkaline earth metal (e.g., using a salt composition which is diluted with CaF 2, BaF 2, MgF 2 , LiF , etc.), and mixed salts thereof . However, these molten salt electrolysis techniques have been put to practical use in alloys and elements having a relatively low melting point such as Mish metal, which are limited to those that can collect the electrolysis-generated metal as a liquid phase. Gd, which has a high melting point,
It is not applied to Tb, etc. This is similar to the case of titanium, when the electrolytic precipitate is collected in the solid phase, the separation of the deposited metal and the molten salt adhering becomes an industrial problem, and in order to collect it as a liquid phase, This is because the problem of the electrolytic cell container that can withstand a high temperature molten salt bath has not been solved.
【００１０】[0010]
【発明が解決しようとする課題】フッ化物中の酸化物の
溶融塩電解還元法により、金属チタンや希土類金属など
の活性な金属が採取できることはよく知られているが、
これらはまだ工業的には実用化されていない。これは、
先にも述べたように、高融点で活性な元素の電解還元に
おいては、溶融塩浴温度を下げて、固相で析出金属を採
取する場合には、析出金属と付着する溶融塩との分離・
回収工程が工業的なプロセスの成立性の上で問題とな
り、また液相で捕集しようとする場合は、従来の電解技
術では、高温の溶融塩浴や析出金属を液相で保持する技
術ができていなかったためである。It is well known that active metals such as metallic titanium and rare earth metals can be collected by the molten salt electrolytic reduction method of oxides in fluoride.
These have not yet been put to practical use industrially. this is,
As mentioned above, in electrolytic reduction of active elements with a high melting point, when the molten salt bath temperature is lowered and the deposited metal is collected in the solid phase, the separated metal and the deposited molten salt are separated.・
When the recovery process becomes a problem in terms of the feasibility of an industrial process, and when it is attempted to collect it in the liquid phase, conventional electrolytic technology requires a technique to hold a molten salt bath at high temperature or a metal deposit in the liquid phase. Because it wasn't done.
【００１１】本発明は上記のような問題点を解決しよう
として行われたものであり、活性で高融点な金属材料を
高効率に電解採取する方法を提供しようとするものであ
る。The present invention has been made in order to solve the above problems, and an object thereof is to provide a method for electrolytically extracting an active and high melting point metal material with high efficiency.
【００１２】[0012]
【課題を解決するための手段】第１発明は、フッ化物を
主成分とする溶融塩浴中に、目的とする活性金属の酸化
物を供給して電解還元し、溶融塩を保持する容器の底部
で電解生成金属を採取する方法において、外側面を強制
冷却した容器の内側面に形成した溶融塩の凝固層を介し
て溶融塩浴を保持し、前記容器の底部に集めた液体状金
属を下方から冷却して、溶融塩浴と接する界面領域は液
相であり、その下部では凝固塊であるような状態に保
ち、溶融塩浴と捕集した液体状金属との界面位置の上昇
とともに、溶融塩浴の上側から浸漬した炭素系材料で構
成される陽極の消耗電極先端を上昇させるチタン等の高
融点な活性金属の溶融塩電解採取方法である。The first aspect of the present invention is directed to a container for holding a molten salt by supplying an oxide of an active metal of interest into a molten salt bath containing a fluoride as a main component and performing electrolytic reduction. In the method of collecting the electrolytically generated metal at the bottom, the molten salt bath is held through the solidified layer of the molten salt formed on the inner surface of the container whose outer surface is forcibly cooled, and the liquid metal collected at the bottom of the container is Cooling from below, the interface area in contact with the molten salt bath is in the liquid phase, and in the lower part it is kept in a state of being a solidified mass, and with the rise of the interface position between the molten salt bath and the collected liquid metal, This is a molten salt electrowinning method of an active metal having a high melting point such as titanium, which raises the tip of the consumable electrode of an anode made of a carbonaceous material immersed from the upper side of the molten salt bath.
【００１３】第２発明は、フッ化物を主成分とする溶融
塩浴中に、目的とする活性金属の酸化物を供給して電解
還元し、溶融塩を保持する容器の底部で電解生成金属を
採取する方法において、外側面を強制冷却した容器の内
側面に形成した溶融塩の凝固層を介して溶融塩浴を保持
し、前記容器の底部に集めた液体状金属を下方から冷却
して、溶融塩浴と接する界面領域は液相であり、その下
部では凝固塊であるような状態に保ち、溶融塩浴と捕集
した液体状金属との界面位置がほぼ一定となるように、
凝固塊を下方に引き抜くとともに、溶融塩浴の上側から
浸漬した炭素系材料で構成される陽極の消耗電極先端位
置をほぼ一定となるように制御するチタン等の高融点な
活性金属の溶融塩電解採取方法である。A second aspect of the invention is to supply an oxide of an active metal of interest to a molten salt bath containing a fluoride as a main component to carry out electrolytic reduction and to produce electrolytically generated metal at the bottom of a container holding the molten salt. In the collecting method, the molten salt bath is held through a solidified layer of molten salt formed on the inner surface of the container whose outer surface is forcibly cooled, and the liquid metal collected at the bottom of the container is cooled from below, The interface region in contact with the molten salt bath is in the liquid phase, and the lower part is kept in a state of being a solidified mass, so that the interface position between the molten salt bath and the collected liquid metal is almost constant,
Molten salt electrolysis of high-melting active metal such as titanium that pulls out the solidified mass downward and controls the tip position of the consumable electrode of the anode made of carbonaceous material soaked from the upper side of the molten salt bath to be almost constant It is a sampling method.
【００１４】第３発明は、溶融塩浴表面を不活性ガス雰
囲気あるいは真空雰囲気とする請求項１または請求項２
のチタン等の高融点な活性金属の溶融塩電解採取方法で
ある。A third aspect of the present invention is that the surface of the molten salt bath is in an inert gas atmosphere or a vacuum atmosphere.
This is a method for electrolytically collecting molten salt of a high melting point active metal such as titanium.
【００１５】[0015]
【作用】以下、本発明の作用について詳述していくこと
にする。本発明は、Ti、Gd、Tbなどの比較的高融点で活
性な金属を、その酸化物から溶融塩電解還元法により、
液相の状態で採取しようとするものである。The operation of the present invention will be described in detail below. The present invention, Ti, Gd, Tb and other active metals with a relatively high melting point, the molten salt electrolytic reduction method from the oxide,
The sample is to be collected in the liquid phase.
【００１６】本発明を達成するための電解槽構造は種々
の方法が考えられるが、基本的には図１および図２に示
すような方法がある。図１は、陽極を上下に移動する方
式で、図中１は容器で、容器１の外側面には冷却箱５を
設け、冷媒７によって強制冷却している。強制冷却する
ことによって、容器１の内側面には溶融塩の凝固層６が
形成される。容器１の底部には、絶縁材８を介して陰極
４があり、陰極４の下面は、容器の外側面と同様に、冷
却箱５内の冷媒７によって強制冷却されている。容器１
内には溶融塩浴２があり、溶融塩浴２には上側から陽極
３が浸漬されている。溶融塩浴２の上部はカバー９でシ
ールされ、カバー９には原料供給口10、不活性ガス供給
・真空排気口11、不活性ガス排出口12が設けてある。陽
極３と陰極４には付加的な交流電源13と電解用直流電源
14とが接続されている。なお、15は生成液体金属を、16
は生成凝固金属をそれぞれ示す。Various methods are conceivable for the structure of the electrolytic cell to achieve the present invention, and basically there is a method as shown in FIGS. 1 and 2. FIG. 1 is a system in which an anode is moved up and down. In the figure, reference numeral 1 is a container, and a cooling box 5 is provided on the outer surface of the container 1, and a cooling medium 7 is forcibly cooled. By forced cooling, a solidified layer 6 of molten salt is formed on the inner surface of the container 1. At the bottom of the container 1, there is a cathode 4 via an insulating material 8, and the lower surface of the cathode 4 is forcibly cooled by the refrigerant 7 in the cooling box 5 like the outer surface of the container. Container 1
There is a molten salt bath 2 therein, and an anode 3 is immersed in the molten salt bath 2 from above. The upper portion of the molten salt bath 2 is sealed by a cover 9, and the cover 9 is provided with a raw material supply port 10, an inert gas supply / vacuum exhaust port 11, and an inert gas exhaust port 12. Additional AC power supply 13 and electrolysis DC power supply for anode 3 and cathode 4
14 and are connected. In addition, 15 is the produced liquid metal, 16
Indicates the produced solidified metal.
【００１７】図２は、凝固塊（生成凝固金属）を下方に
引き抜く方式で、図中１は容器で、容器１の外側面には
冷却箱５を設け、冷媒７によって強制冷却している。強
制冷却することによって、容器１の内側面には溶融塩の
凝固層６が形成される。容器１の底部には、下方に移動
する陰極４があり、生成凝固金属16を下方に引き抜くこ
とが可能である。また、容器１の底部には、高温の生成
凝固金属16を大気から保護するためにカバー17が設けて
ある。容器１内には溶融塩浴２があり、溶融塩浴２には
上側から陽極３が浸漬されている。溶融塩浴２の上部は
カバー９でシールされ、カバー９には原料供給口10が設
けてある。陽極３と陰極４には電解用直流電源14が接続
されている。なお、15は生成液体金属を示す。FIG. 2 shows a system in which a solidified lump (produced solidified metal) is drawn downward. In the figure, reference numeral 1 is a container, and a cooling box 5 is provided on the outer surface of the container 1 and is forcibly cooled by a refrigerant 7. By forced cooling, a solidified layer 6 of molten salt is formed on the inner surface of the container 1. At the bottom of the container 1 is a downwardly moving cathode 4 which allows the produced solidified metal 16 to be drawn downwards. A cover 17 is provided at the bottom of the container 1 to protect the produced and solidified metal 16 at high temperature from the atmosphere. A molten salt bath 2 is provided in the container 1, and an anode 3 is immersed in the molten salt bath 2 from above. The upper part of the molten salt bath 2 is sealed by a cover 9, and the cover 9 is provided with a raw material supply port 10. A DC power supply 14 for electrolysis is connected to the anode 3 and the cathode 4. In addition, 15 indicates a produced liquid metal.
【００１８】電解質としては、アルカリ金属のフッ化物
（LiF 他) 、アルカリ土類金属のフッ化物（CaF2、Mg
F2、BaF2等) の単一または混合塩を基本組成とし、これ
に電解還元を目的とする金属酸化物を添加した組成の塩
を用いるが、必要に応じてそれぞれの金属の塩化物を添
加した塩を用いることも可能である。As the electrolyte, alkali metal fluorides (LiF, etc.), alkaline earth metal fluorides (CaF 2 , Mg
(F 2 , BaF 2 etc.) single or mixed salt is used as a basic composition, and a salt having a composition in which a metal oxide for the purpose of electrolytic reduction is added is used.A chloride of each metal may be added as necessary. It is also possible to use added salts.
【００１９】電解質の加熱溶融方式は、塩自体に通電し
て発熱させる内部加熱方式とし、直流の電解電流自体で
加熱溶融させる方式と、図１に示す交流電流を通電して
加熱溶融し、これに電解のための直流電流を重畳する方
式のいずれでも可能である。The heating and melting method of the electrolyte is an internal heating method in which the salt itself is energized to generate heat, and the method of heating and melting is performed by a direct electrolytic current itself, and the alternating current shown in FIG. Any of the methods in which a direct current for electrolysis is superposed is also possible.
【００２０】電解還元の原料となる酸化物の供給は、使
用する溶融塩浴の酸化物溶解度の範囲内とするのが望ま
しい。この理由は、酸化物の密度は溶融塩浴の密度より
大きく、またその融点も高いため、過剰に供給しすぎる
と溶融塩浴底部に沈澱して、これが電解生成金属を汚染
するなどの問題の原因となるためである。チタンの場合
は、フッ化物浴中のチタン酸化物の溶解度は50wt％程度
はあり、比較的余裕があるが、希土類元素の場合は、そ
の酸化物の溶解度は数％程度であると報告されており、
溶融塩浴中への酸化物の供給が過剰になりやすい。It is desirable that the supply of the oxide as a raw material for electrolytic reduction is within the range of the oxide solubility of the molten salt bath used. The reason for this is that the density of the oxide is higher than that of the molten salt bath, and its melting point is also high. Therefore, if too much is supplied, it will precipitate at the bottom of the molten salt bath, which will contaminate the electrolytically generated metal. This is because it becomes a cause. In the case of titanium, the solubility of titanium oxide in the fluoride bath is about 50 wt%, which is relatively large, but in the case of rare earth elements, the solubility of the oxide is reported to be about several%. Cage,
Excessive supply of oxide into the molten salt bath tends to occur.
【００２１】金属Tiを液相で採取すためには、Tiの融点
(1670℃) 以上の溶融塩浴温度とする必要がある。この
ような高温でも蒸発ロスの少ない溶融塩としては、Ca
F2、BaF2などがあり、本発明のような電解還元ではない
が、チタンのエレクトロスラグ再溶解用のスラグとして
利用された研究報告はある。本発明では、電解質として
はCaF2、BaF2などを主成分とし、これにTi酸化物などを
添加した組成を用い、これを1670℃以上の温度で保持す
ることになる。In order to collect metallic Ti in the liquid phase, the melting point of Ti is
It is necessary to keep the molten salt bath temperature at (1670 ℃) or higher. As a molten salt with little evaporation loss even at such high temperature, Ca
There are F 2 and BaF 2 etc., which are not electrolytic reduction as in the present invention, but there are research reports utilized as slag for remelting electroslag of titanium. In the present invention, as the electrolyte, a composition containing CaF 2 , BaF 2 and the like as a main component, and a Ti oxide and the like added thereto is used, and this is maintained at a temperature of 1670 ° C. or higher.
【００２２】金属Gd、Tbなどを液相で採取するために
は、Gd融点 (1312℃) 、Tb融点 (1357℃) 以上の溶融塩
浴温度とする必要があるが、この場合はTiの場合と比べ
て融点の低い溶融塩の利用も可能であり、CaF2、BaF2、
MgF2、LiF などを主成分とする混合塩に、これら金属の
酸化物を添加した組成となる。これらの塩を金属の融点
以上の温度で保持する必要がある。In order to collect metals such as Gd and Tb in the liquid phase, it is necessary to set the molten salt bath temperature to the melting point of Gd (1312 ° C) or Tb (1357 ° C) or higher. In this case, Ti is used. It is also possible to use a molten salt having a lower melting point than that of CaF 2 , BaF 2 ,
The composition is such that oxides of these metals are added to a mixed salt containing MgF 2 , LiF, etc. as main components. It is necessary to keep these salts at a temperature above the melting point of the metal.
【００２３】本発明を達成するためには、腐食性の強い
フッ化物浴を先に述べたような高温度で安定に保持する
必要があるが、これを達成手段として、図１に模式的に
示すように、外側面を強制冷却した金属製の容器１を用
い、容器内の溶融塩浴２自体に通電して発熱溶融させ、
容器１と接する領域においてのみ強制冷却の効果により
溶融塩の凝固層６を容器内側面に形成させる方式を用い
る。In order to achieve the present invention, it is necessary to hold a highly corrosive fluoride bath stably at the high temperature as described above, and this is schematically shown in FIG. As shown, a metal container 1 whose outer surface is forcibly cooled is used, and a molten salt bath 2 in the container is energized to generate heat and melt,
A method is used in which the solidified layer 6 of molten salt is formed on the inner surface of the container by the effect of forced cooling only in the region in contact with the container 1.
【００２４】典型的な強制冷却された容器１として、外
側面を水で冷却した銅あるいはステンレス鋼製の容器が
あるが、冷媒７としては、水のほかにガスや液体金属な
どを用いることも可能であり、容器材質としては熱伝導
性の良好な材料であれば適用できる。As a typical forcedly cooled container 1, there is a container made of copper or stainless steel whose outer surface is cooled by water, but as the refrigerant 7, gas or liquid metal may be used in addition to water. It is possible, and as the material of the container, any material having good thermal conductivity can be applied.
【００２５】溶融塩浴２での発熱速度と容器１からの冷
却速度とのバランスにより、溶融塩の凝固層６の厚さを
1mmから数十mm程度に制御することができる。このよう
に、溶融塩の凝固層を強制的に形成させることにより、
容器と接する領域の溶融塩の温度を著しく低下させるこ
とが可能となり、容器の腐食が防止できるとともに、溶
融塩浴自体の容器の溶損による汚染も回避できる。この
ような手段により、従来困難であった非常に高温なフッ
化物浴を安定に保持することが可能となり、本発明のよ
うな高温での電解還元が可能となった。The thickness of the solidified layer 6 of the molten salt is controlled by the balance between the heat generation rate in the molten salt bath 2 and the cooling rate from the container 1.
It can be controlled from 1 mm to several tens of mm. In this way, by forcibly forming a solidified layer of molten salt,
It is possible to significantly lower the temperature of the molten salt in the region in contact with the container, prevent corrosion of the container, and avoid contamination of the molten salt bath itself due to melting damage of the container. By such means, it became possible to stably hold a very high temperature fluoride bath, which was difficult in the past, and it became possible to carry out electrolytic reduction at a high temperature as in the present invention.
【００２６】電解還元方法は、図１に模式的に示すよう
に、陽極３として炭素系材料で構成される消耗電極を溶
融塩浴２の上側から浸漬し、電解生成金属浴自体を陰極
４とし、原料となる酸化物を原料供給口10から適宜添加
して電解還元を行い、陰極４に生成金属を捕集する。こ
の際、陽極３からは電極の Cと溶融塩浴２中の酸素イオ
ンが反応してCOガスが発生する。フッ化物の溶融塩電解
では、陽極において発生するフッ素と電極の黒鉛が反応
してフッ化炭素を生成し、電極を不活性化するというア
ノード効果という問題を含んでいるが、本発明では、酸
化物の電解であるため、陽極生成ガスはCOガスであり、
アノード効果はない。In the electrolytic reduction method, as shown schematically in FIG. 1, a consumable electrode made of a carbonaceous material is immersed as the anode 3 from above the molten salt bath 2, and the electrolytically-produced metal bath itself is used as the cathode 4. Then, an oxide as a raw material is appropriately added from the raw material supply port 10 to carry out electrolytic reduction to collect the produced metal in the cathode 4. At this time, C of the electrode reacts with oxygen ions in the molten salt bath 2 from the anode 3 to generate CO gas. In the molten salt electrolysis of fluoride, fluorine generated at the anode and graphite of the electrode react with each other to generate fluorocarbon, which causes a problem of the anode effect of deactivating the electrode. Since it is the electrolysis of substances, the gas produced by the anode is CO gas,
There is no anode effect.
【００２７】Ti、Gd、Tbなどの液体状態は、非常に高温
ということもあり極めて活性である。そのため、液相の
状態で長時間保持し続けると、著しい酸素、窒素のピッ
クアップが起こる。特に、電解還元プロセスは長時間操
業となるため、とりわけこの影響をうけやすい。本発明
は、この問題を解決するため、捕集した液体状金属の下
方から冷却して、溶融塩浴と接する界面領域は液相であ
るが、その下部では凝固塊であるような状態を保ちなが
ら電解操業を行う。これは、本方式のような内部発熱方
式の場合、主な発熱領域が溶融塩浴となるため、冷却と
のバランスにより比較的容易に達成できる。The liquid state of Ti, Gd, Tb, etc. is extremely active because it may be at a very high temperature. Therefore, if the liquid phase is kept for a long time, significant oxygen and nitrogen pickup occurs. In particular, the electrolytic reduction process operates for a long period of time and is particularly susceptible to this effect. In order to solve this problem, the present invention cools the collected liquid metal from below and maintains a state in which the interface region in contact with the molten salt bath is in the liquid phase, but below it is a solidified mass. While performing electrolytic operation. In the case of the internal heating method such as this method, this is relatively easy to achieve due to the balance with cooling because the main heating area is the molten salt bath.
【００２８】電解還元の進行とともに、溶融塩浴２と生
成液体金属15との界面の位置が徐々に上昇するため、そ
の上にある溶融塩浴２の位置も上昇することとなる。溶
融塩浴に入力する電力（電流×電圧）は出来るだけ一定
に制御しておくことが電解操業の安定性の上で重要なた
め、溶融塩浴の上昇に伴い、陽極３もその先端位置と液
体金属−溶融塩浴界面位置との距離が出来るだけ一定と
なるように上昇させることが必要である。As the electrolytic reduction proceeds, the position of the interface between the molten salt bath 2 and the produced liquid metal 15 gradually rises, so that the position of the molten salt bath 2 above it also rises. Since it is important for the stability of the electrolytic operation to control the electric power (current x voltage) input to the molten salt bath as much as possible, as the molten salt bath rises, the anode 3 also moves to its tip position. It is necessary to raise it so that the distance from the liquid metal-molten salt bath interface position is as constant as possible.
【００２９】また、電解還元の進行に伴い、液体金属−
溶融塩浴界面の位置が逐次上昇するが、この界面位置を
固定して、凝固させた生成凝固金属16を下方に引き抜く
ことも可能である。この方式の場合、図２に示すよう
に、溶融塩浴を保持する領域と、電解生成金属を捕集す
る陰極４の領域の寸法を自由に選べるとともに、長時間
の電解操業が可能となる利点がある。Further, with the progress of electrolytic reduction, liquid metal-
Although the position of the interface of the molten salt bath gradually rises, it is also possible to fix this interface position and pull out the solidified produced solidified metal 16 downward. In the case of this system, as shown in FIG. 2, it is possible to freely select the dimensions of the region holding the molten salt bath and the region of the cathode 4 that collects the electrolytically generated metal, and it is possible to operate for a long time. There is.
【００３０】Ti、Gd、Tbなどの活性で高融点な金属の電
解還元採取を行う場合、雰囲気からの酸化、窒化などの
汚染が起こりやすい。大気雰囲気下でも溶融塩浴に保護
されているため電解操業自体は可能であるが、汚染の防
止には、図１に示すようなカバー９を設けて、雰囲気を
アルゴンやヘリウムなどの不活性ガス雰囲気あるいは真
空などの雰囲気とすることがより有効である。When electrolytic reduction extraction of an active metal having a high melting point, such as Ti, Gd, or Tb, contamination such as oxidation or nitriding from the atmosphere is likely to occur. Although the electrolytic operation itself is possible because it is protected by the molten salt bath even in the air atmosphere, in order to prevent contamination, a cover 9 as shown in FIG. 1 is provided and the atmosphere is an inert gas such as argon or helium. An atmosphere or an atmosphere such as a vacuum is more effective.
【００３１】以上のように、本発明の方法では、金属を
液相で捕集して溶融塩との分離を行い、凝固塊の形で直
接的に鋳塊を取り出すことが可能なため、チタン製品の
内の成分規格の面で問題のない場合は、直接に圧延工程
にかけることが可能となり、工程省略効果も大きい。As described above, in the method of the present invention, the metal can be collected in the liquid phase to separate it from the molten salt, and the ingot can be directly taken out in the form of a solidified ingot. If there is no problem in terms of component specifications in the product, it is possible to directly apply the rolling process, and the effect of omitting the process is great.
【００３２】[0032]
【実施例】以下に本発明の実施例について説明する。実
施例で使用した電解槽は、容器には内径80mm、高さ300m
m の水冷銅製容器を用い、電極には直径50mmの炭素質材
の陽極と、直径95mm、高さ50mmのTi陰極を用い、電解還
元雰囲気は不活性ガス雰囲気とし、Arガスを5l/min流し
た。電源には最大1500A の直流電源を用いた。EXAMPLES Examples of the present invention will be described below. The electrolytic cell used in the example has an inner diameter of 80 mm and a height of 300 m in the container.
A water-cooled copper container of m 2 was used, a carbonaceous material anode with a diameter of 50 mm and a Ti cathode with a diameter of 95 mm and a height of 50 mm were used for the electrodes, the electrolytic reduction atmosphere was an inert gas atmosphere, and Ar gas was 5 l / min flow. did. A maximum of 1500 A DC power supply was used as the power supply.
【００３３】電解操業では、CaF2：60wt％、BaF2：30wt
％、TiO2：10wt％組成の溶融塩浴を最高1700℃に保持
し、電解電流1500A 、電解電圧15V で、10時間電解還元
を行った。なお、電解操業中は原料としてTiO2を溶融塩
浴組成に合わせて添加し続けた。In electrolytic operation, CaF 2 : 60 wt%, BaF 2 : 30 wt%
%, TiO 2: a molten salt bath of 10 wt% composition was held to a maximum 1700 ° C., electrolysis current 1500A, in electrolysis voltage 15V, it was carried out for 10 hours electrolytic reduction. During the electrolytic operation, TiO 2 was continuously added as a raw material according to the composition of the molten salt bath.
【００３４】その結果、容器底部で溶融塩と完全に分離
された状態で、凝固した溶融塩にくるまれる形態で、約
1kgの金属Tiを採取することができた。この結果より電
力効率を計算すると15％となる。As a result, in a state in which it is completely separated from the molten salt at the bottom of the container, it is wrapped in the solidified molten salt,
It was possible to collect 1 kg of metallic Ti. The power efficiency calculated from this result is 15%.
【００３５】[0035]
【発明の効果】以上説明したように、本発明に係わるチ
タン等の高融点な活性金属の溶融塩電解採取方法は、フ
ッ化物を主成分とする溶融塩浴中に、目的とする活性金
属の酸化物を供給して電解還元し、溶融塩を保持する容
器の底部で電解生成金属を採取する方法において、不活
性ガス雰囲気または真空雰囲気中で、外側面を強制冷却
した容器の内側面に形成した溶融塩の凝固層を介して溶
融塩浴を保持し、前記容器の底部に集めた液体状金属を
下方から冷却して、溶融塩浴と接する界面領域は液相で
あり、その下部では凝固塊であるような状態に保ち、溶
融塩浴と捕集した液体状金属との界面位置の上昇ととも
に、溶融塩浴の上側から浸漬した炭素系材料で構成され
る陽極の消耗電極先端を上昇させるか、または溶融塩浴
と捕集した液体状金属との界面位置がほぼ一定となるよ
うに、凝固塊を下方に引き抜くとともに、溶融塩浴の上
側から浸漬した炭素系材料で構成される陽極の消耗電極
先端位置をほぼ一定となるように制御するチタン等の高
融点な活性金属の溶融塩電解採取方法であって、本発明
法によれば、溶融塩の凝固層を強制的に形成させること
により、容器の腐食が防止できるとともに、溶融塩浴自
体の容器の溶損による汚染も回避できる。また、捕集し
た液体状金属を下方から冷却することにより下部を凝固
塊とすることによって、長時間操業においても酸素、窒
素のピックアップを防止することができ、凝固塊を下方
に引き抜く方式にすることによって、溶融塩浴を保持す
る領域と、電解生成金属を捕集する陰極の領域の寸法を
自由に選べるとともに、長時間の電解操業が可能となる
利点がある。さらに、不活性ガス雰囲気あるいは真空な
どの雰囲気とすることにより、電解操業中の酸化、窒化
などの汚染を防止することができるとともに、金属を液
相で捕集して溶融塩との分離を行い、凝固塊の形で直接
的に鋳塊を取り出すことが可能であるという多くの優れ
た効果を有するものである。As described above, the molten salt electrowinning method for a high melting point active metal such as titanium according to the present invention is carried out in a molten salt bath containing a fluoride as a main component. In the method of supplying electrolytic oxide to perform electrolytic reduction and collecting electrolytically generated metal at the bottom of the container that holds the molten salt, the outer surface is formed on the inner surface of the container whose outer surface is forcibly cooled in an inert gas atmosphere or a vacuum atmosphere. The molten salt bath is held through the solidified layer of the molten salt, the liquid metal collected at the bottom of the container is cooled from below, and the interface region in contact with the molten salt bath is in the liquid phase, and the solidified portion is below it. Keeping the state like a lump, as the position of the interface between the molten salt bath and the collected liquid metal rises, the tip of the consumable electrode of the anode composed of the carbonaceous material immersed from the upper side of the molten salt bath rises. Or molten liquid with a molten salt bath The solidified mass is pulled downward so that the interface position with the metal is almost constant, and the tip of the consumable electrode of the anode made of carbonaceous material immersed from the upper side of the molten salt bath is controlled to be almost constant. According to the method of the present invention, which is a molten salt electrowinning method of a high-melting active metal such as titanium, by forcibly forming a solidified layer of the molten salt, corrosion of the container can be prevented and the molten salt can be prevented. Contamination due to melting damage of the container of the bath itself can also be avoided. Also, by cooling the collected liquid metal from below to form a solidified mass in the lower part, it is possible to prevent oxygen and nitrogen from being picked up even during long-term operation, and the solidified mass is pulled out downward. As a result, the size of the region holding the molten salt bath and the size of the region of the cathode that collects the electrolytically-generated metal can be freely selected, and there is an advantage that a long-time electrolytic operation can be performed. Furthermore, by using an inert gas atmosphere or an atmosphere such as a vacuum, it is possible to prevent contamination such as oxidation and nitridation during the electrolytic operation, and to collect the metal in the liquid phase and separate it from the molten salt. It has many excellent effects that the ingot can be directly taken out in the form of a solidified ingot.
【図１】本発明による陽極を上下に移動する方式のチタ
ン等の高融点な活性金属の溶融塩電解採取方法の模式図
を示す図である。FIG. 1 is a diagram showing a schematic diagram of a method for electrolytically collecting a molten salt of a high melting point active metal such as titanium by moving an anode up and down according to the present invention.
【図２】本発明による凝固塊を下方に引き抜く方式のチ
タン等の高融点な活性金属の溶融塩電解採取方法の模式
図を示す図である。FIG. 2 is a diagram showing a schematic diagram of a method for electrolytically collecting a molten salt of a high melting point active metal such as titanium by a method of extracting a solidified mass downward according to the present invention.
１…容器、２…溶融塩浴、３…陽極、４…陰極、５…冷
却箱、６…凝固層、７…冷媒、８…絶縁材、９…カバ
ー、10…原料供給口、11…不活性ガス供給・真空排気
口、12…不活性ガス排出口、13…交流電源、14…直流電
源、15…生成液体金属、16…生成凝固金属、17…カバ
ー。DESCRIPTION OF SYMBOLS 1 ... Container, 2 ... Molten salt bath, 3 ... Anode, 4 ... Cathode, 5 ... Cooling box, 6 ... Solidification layer, 7 ... Refrigerant, 8 ... Insulating material, 9 ... Cover, 10 ... Raw material supply port, 11 ... No Active gas supply / vacuum exhaust port, 12 ... Inert gas exhaust port, 13 ... AC power source, 14 ... DC power source, 15 ... Generated liquid metal, 16 ... Generated solidified metal, 17 ... Cover.
Claims (3)
目的とする活性金属の酸化物を供給して電解還元し、溶
融塩を保持する容器の底部で電解生成金属を採取する方
法において、外側面を強制冷却した容器の内側面に形成
した溶融塩の凝固層を介して溶融塩浴を保持し、前記容
器の底部に集めた液体状金属を下方から冷却して、溶融
塩浴と接する界面領域は液相であり、その下部では凝固
塊であるような状態に保ち、溶融塩浴と捕集した液体状
金属との界面位置の上昇とともに、溶融塩浴の上側から
浸漬した炭素系材料で構成される陽極の消耗電極先端を
上昇させるこを特徴とするチタン等の高融点な活性金属
の溶融塩電解採取方法。1. A molten salt bath containing fluoride as a main component,
In the method of supplying the target active metal oxide to perform electrolytic reduction and collecting the electrolytically-generated metal at the bottom of the container holding the molten salt, the molten salt formed on the inner surface of the container whose outer surface is forcibly cooled The molten salt bath is held through the solidification layer, and the liquid metal collected at the bottom of the container is cooled from below, so that the interface region in contact with the molten salt bath is the liquid phase, and the solidified mass is below it. In this state, the tip of the consumable electrode of the anode made of the carbonaceous material immersed from the upper side of the molten salt bath is raised as the interface position between the molten salt bath and the collected liquid metal is raised. Method for electrowinning molten salt of high melting point active metal such as titanium.
目的とする活性金属の酸化物を供給して電解還元し、溶
融塩を保持する容器の底部で電解生成金属を採取する方
法において、外側面を強制冷却した容器の内側面に形成
した溶融塩の凝固層を介して溶融塩浴を保持し、前記容
器の底部に集めた液体状金属を下方から冷却して、溶融
塩浴と接する界面領域は液相であり、その下部では凝固
塊であるような状態に保ち、溶融塩浴と捕集した液体状
金属との界面位置がほぼ一定となるように、凝固塊を下
方に引き抜くとともに、溶融塩浴の上側から浸漬した炭
素系材料で構成される陽極の消耗電極先端位置をほぼ一
定となるように制御することを特徴とするチタン等の高
融点な活性金属の溶融塩電解採取方法。2. In a molten salt bath containing fluoride as a main component,
In the method of supplying the target active metal oxide to perform electrolytic reduction and collecting the electrolytically-generated metal at the bottom of the container holding the molten salt, the molten salt formed on the inner surface of the container whose outer surface is forcibly cooled The molten salt bath is held through the solidification layer, and the liquid metal collected at the bottom of the container is cooled from below, so that the interface region in contact with the molten salt bath is the liquid phase, and the solidified mass is below it. In this state, the solidified mass is drawn downward so that the interface position between the molten salt bath and the collected liquid metal is almost constant, and it is composed of a carbon-based material immersed from the upper side of the molten salt bath. A method for electrowinning molten salt of an active metal having a high melting point such as titanium, characterized in that the position of the tip of the consumable electrode of the anode is controlled to be substantially constant.
は真空雰囲気とする請求項１または請求項２のチタン等
の高融点な活性金属の溶融塩電解採取方法。3. The molten salt electrowinning method for an active metal having a high melting point such as titanium according to claim 1 or 2, wherein the surface of the molten salt bath is an inert gas atmosphere or a vacuum atmosphere.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29324892A JPH06146049A (en) | 1992-10-30 | 1992-10-30 | Molten salt electrolytic sampling method for high-fusion-point active metal such as titanium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29324892A JPH06146049A (en) | 1992-10-30 | 1992-10-30 | Molten salt electrolytic sampling method for high-fusion-point active metal such as titanium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06146049A true JPH06146049A (en) | 1994-05-27 |
Family
ID=17792365
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29324892A Withdrawn JPH06146049A (en) | 1992-10-30 | 1992-10-30 | Molten salt electrolytic sampling method for high-fusion-point active metal such as titanium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06146049A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5914531A (en) * | 1994-02-10 | 1999-06-22 | Hitachi, Ltd. | Semiconductor device having a ball grid array package structure using a supporting frame |
| EP1249516A3 (en) * | 2001-04-10 | 2003-05-14 | Heinz Prof. Dr. Mitbauer | Process and apparatus for carrying out a chlor-alkali molten salt electrolysis |
| JP2004530798A (en) * | 2001-06-29 | 2004-10-07 | ビーエイチピー ビリトン イノベーション プロプライアタリー リミテッド | Reduction of metal oxides in electrolytic cells |
| JP2004537654A (en) * | 2001-08-16 | 2004-12-16 | ビーエイチピー ビリトン イノベーション プロプライアタリー リミテッド | Method for producing titanium and titanium alloy products |
| JP2007204797A (en) * | 2006-01-31 | 2007-08-16 | Toyohashi Univ Of Technology | Molten-salt electrolysis apparatus for metal, and method for producing metal with the use of the apparatus |
| JP2008195969A (en) * | 2007-02-08 | 2008-08-28 | Toyohashi Univ Of Technology | Method for manufacturing alloy ingot by molten salt electrolysis using esr heating |
| WO2014008410A1 (en) * | 2012-07-03 | 2014-01-09 | Ceramatec, Inc. | Apparatus and method of producing metal in a nasicon electrolytic cell |
| CN107130267A (en) * | 2017-06-27 | 2017-09-05 | 包头稀土研究院 | Fused salt electrolysis process produces the device of metal or alloy |
| KR20190045582A (en) * | 2017-10-24 | 2019-05-03 | 연세대학교 산학협력단 | Method and apparatus for refining metal |
| WO2022108007A1 (en) * | 2020-11-17 | 2022-05-27 | 주식회사 케이에스엠테크놀로지 | Reduction method and system for high-melting-point metal oxide, using fluoride-based electrolytes |
-
1992
- 1992-10-30 JP JP29324892A patent/JPH06146049A/en not_active Withdrawn
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5914531A (en) * | 1994-02-10 | 1999-06-22 | Hitachi, Ltd. | Semiconductor device having a ball grid array package structure using a supporting frame |
| EP1249516A3 (en) * | 2001-04-10 | 2003-05-14 | Heinz Prof. Dr. Mitbauer | Process and apparatus for carrying out a chlor-alkali molten salt electrolysis |
| JP2004530798A (en) * | 2001-06-29 | 2004-10-07 | ビーエイチピー ビリトン イノベーション プロプライアタリー リミテッド | Reduction of metal oxides in electrolytic cells |
| JP2004537654A (en) * | 2001-08-16 | 2004-12-16 | ビーエイチピー ビリトン イノベーション プロプライアタリー リミテッド | Method for producing titanium and titanium alloy products |
| JP2007204797A (en) * | 2006-01-31 | 2007-08-16 | Toyohashi Univ Of Technology | Molten-salt electrolysis apparatus for metal, and method for producing metal with the use of the apparatus |
| JP2008195969A (en) * | 2007-02-08 | 2008-08-28 | Toyohashi Univ Of Technology | Method for manufacturing alloy ingot by molten salt electrolysis using esr heating |
| JP4707036B2 (en) * | 2007-02-08 | 2011-06-22 | 国立大学法人豊橋技術科学大学 | Method for producing alloy ingot by molten salt electrolysis using ESR heating |
| WO2014008410A1 (en) * | 2012-07-03 | 2014-01-09 | Ceramatec, Inc. | Apparatus and method of producing metal in a nasicon electrolytic cell |
| CN107130267A (en) * | 2017-06-27 | 2017-09-05 | 包头稀土研究院 | Fused salt electrolysis process produces the device of metal or alloy |
| KR20190045582A (en) * | 2017-10-24 | 2019-05-03 | 연세대학교 산학협력단 | Method and apparatus for refining metal |
| WO2022108007A1 (en) * | 2020-11-17 | 2022-05-27 | 주식회사 케이에스엠테크놀로지 | Reduction method and system for high-melting-point metal oxide, using fluoride-based electrolytes |
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Legal Events
| Date | Code | Title | Description |
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| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20000104 |