JP6299181B2 - Recovery method of rare earth elements - Google Patents
Recovery method of rare earth elements Download PDFInfo
- Publication number
- JP6299181B2 JP6299181B2 JP2013245620A JP2013245620A JP6299181B2 JP 6299181 B2 JP6299181 B2 JP 6299181B2 JP 2013245620 A JP2013245620 A JP 2013245620A JP 2013245620 A JP2013245620 A JP 2013245620A JP 6299181 B2 JP6299181 B2 JP 6299181B2
- Authority
- JP
- Japan
- Prior art keywords
- rare earth
- powder
- earth element
- treated
- carbon
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Description
本発明は、例えばＲ−Ｆｅ−Ｂ系永久磁石（Ｒは希土類元素）などの、少なくとも希土類元素と鉄族元素を含む処理対象物から希土類元素を回収する方法に関する。 The present invention relates to a method for recovering a rare earth element from a processing object including at least a rare earth element and an iron group element, such as an R—Fe—B permanent magnet (R is a rare earth element).
Ｒ−Ｆｅ−Ｂ系永久磁石は、高い磁気特性を有していることから、今日様々な分野で使用されていることは周知の通りである。このような背景のもと、Ｒ−Ｆｅ−Ｂ系永久磁石の生産工場では、日々、大量の磁石が生産されているが、磁石の生産量の増大に伴い、製造工程中に加工不良物などとして排出される磁石スクラップや、切削屑や研削屑などとして排出される磁石加工屑などの量も増加している。とりわけ情報機器の軽量化や小型化によってそこで使用される磁石も小型化していることから、加工代比率が大きくなることで、製造歩留まりが年々低下する傾向にある。従って、製造工程中に排出される磁石スクラップや磁石加工屑などを廃棄せず、そこに含まれる金属元素、特に希土類元素をいかに回収して再利用するかが今後の重要な技術課題となっている。また、Ｒ−Ｆｅ−Ｂ系永久磁石を使用した電化製品などから循環資源として希土類元素をいかに回収して再利用するかについても同様である。 As is well known, R-Fe-B permanent magnets are used in various fields today because of their high magnetic properties. Against this backdrop, R-Fe-B permanent magnet production plants produce a large amount of magnets every day, but due to the increase in production of magnets, processing defects etc. during the manufacturing process. As a result, the amount of magnet scrap discharged as magnets and magnet processed scraps discharged as cutting scraps, grinding scraps, and the like is also increasing. In particular, since the magnets used therein are also downsized due to the weight reduction and downsizing of information equipment, the processing yield ratio tends to increase and the manufacturing yield tends to decrease year by year. Therefore, it will be an important technical issue in the future how to recover and reuse the metal elements, especially rare earth elements, without discarding the magnet scraps and magnet processing scraps discharged during the manufacturing process. Yes. The same applies to how rare earth elements are recovered and reused as recycled resources from electrical appliances using R-Fe-B permanent magnets.
少なくとも希土類元素と鉄族元素を含む処理対象物から希土類元素を回収する方法については、これまでにもいくつかの方法が提案されており、例えば特許文献１では、処理対象物を酸化性雰囲気中で加熱して含有金属元素を酸化物とした後、水と混合してスラリーとし、加熱しながら塩酸を加えて希土類元素を溶液に溶解させ、得られた溶液に加熱しながらアルカリ（水酸化ナトリウムやアンモニアや水酸化カリウムなど）を加えることで、希土類元素とともに溶液に浸出した鉄族元素を沈殿させた後、溶液を未溶解物と沈殿物から分離し、溶液に沈殿剤として例えばシュウ酸を加えて希土類元素をシュウ酸塩として回収する方法が提案されている。この方法は、希土類元素を鉄族元素と効果的に分離して回収することができる方法として注目に値する。しかしながら、工程の一部に酸やアルカリを用いることから、工程管理が容易ではなく、また、回収コストが高くつくといった問題がある。従って、特許文献１に記載の方法は、低コストと簡易さが要求されるリサイクルシステムとして実用化するには困難な側面を有するといわざるを得ない。
また、特許文献２では、処理対象物に含まれる鉄族元素を酸化することなく希土類元素のみを酸化することによって両者を分離する方法として、処理対象物を炭素るつぼの中で加熱する方法が提案されている。この方法は、特許文献１に記載の方法のように酸やアルカリを必要とせず、また、炭素るつぼの中で処理対象物を加熱することで理論的にるつぼ内の雰囲気が鉄族元素が酸化されることなく希土類元素のみが酸化される酸素分圧に自律的に制御されることから、特許文献１に記載の方法に比較して工程が簡易であるという点において優れていると考えられる。しかしながら、単に処理対象物を炭素るつぼの中で加熱すればるつぼ内の雰囲気が所定の酸素分圧に自律的に制御されて希土類元素と鉄族元素を分離できるのかといえば、現実的には必ずしもそうではない。特許文献２では、るつぼ内の雰囲気の望ましい酸素含有濃度は１ｐｐｍ〜１％であるとされているが、本質的には雰囲気を制御するための外的操作は必要とされないとある。しかしながら、本発明者らの検討によれば、少なくとも酸素含有濃度が１ｐｐｍ未満の場合には希土類元素と鉄族元素は分離できない。従って、炭素るつぼの中で処理対象物を加熱すれば、理論的にはるつぼ内の雰囲気が鉄族元素が酸化されることなく希土類元素のみが酸化される酸素分圧に自律的に制御されるとしても、現実的にはるつぼ内を酸素含有濃度が１ｐｐｍ以上の雰囲気に人為的に制御する必要がある。こうした制御は、特許文献２にも記載されているように酸素含有濃度が１ｐｐｍ以上の不活性ガスをるつぼ内に導入することで行うことができるが、工業用不活性ガスとして汎用されているアルゴンガスの場合、その酸素含有濃度は通常０．５ｐｐｍ以下である。従って、酸素含有濃度が１ｐｐｍ以上のアルゴンガスをるつぼ内に導入するためには、汎用されているアルゴンガスをそのまま用いることはできず、その酸素含有濃度をわざわざ高めた上で用いる必要がある。結果として、特許文献２に記載の方法は、一見工程が簡易に思えるものの実はそうではなく、特許文献１に記載の方法と同様、低コストと簡易さが要求されるリサイクルシステムとして実用化するには困難な側面を有するといわざるを得ない。
As a method for recovering rare earth elements from a processing object containing at least a rare earth element and an iron group element, several methods have been proposed so far. For example, in Patent Document 1, the processing object is placed in an oxidizing atmosphere. After heating to obtain an oxide of the contained metal element, it is mixed with water to form a slurry, and hydrochloric acid is added with heating to dissolve the rare earth element in the solution. The resulting solution is heated with an alkali (sodium hydroxide) , Ammonia, potassium hydroxide, etc.) to precipitate the iron group element leached into the solution together with the rare earth element, and then separate the solution from the undissolved material and the precipitate. In addition, methods for recovering rare earth elements as oxalates have been proposed. This method is remarkable as a method capable of effectively separating and recovering rare earth elements from iron group elements. However, since acid or alkali is used in a part of the process, there is a problem that process management is not easy and the recovery cost is high. Therefore, it can be said that the method described in Patent Document 1 has a difficult aspect for practical use as a recycling system that requires low cost and simplicity.
Moreover, in patent document 2, the method of heating a process target object in a carbon crucible is proposed as a method of isolate | separating both by oxidizing only a rare earth element, without oxidizing the iron group element contained in a process target object. Has been. This method does not require an acid or alkali like the method described in Patent Document 1, and the atmosphere in the crucible is theoretically oxidized by oxidizing the iron group element by heating the object to be processed in the carbon crucible. Therefore, it is considered that the method is superior in that the process is simple compared to the method described in Patent Document 1 because it is autonomously controlled to the oxygen partial pressure at which only rare earth elements are oxidized. However, in reality, if the object to be treated is simply heated in a carbon crucible, the atmosphere in the crucible can be autonomously controlled to a predetermined oxygen partial pressure to separate the rare earth element and the iron group element. It is not. In Patent Document 2, the desirable oxygen-containing concentration of the atmosphere in the crucible is 1 ppm to 1%, but there is essentially no need for an external operation for controlling the atmosphere. However, according to the study by the present inventors, rare earth elements and iron group elements cannot be separated at least when the oxygen-containing concentration is less than 1 ppm. Therefore, if the object to be treated is heated in a carbon crucible, the atmosphere in the crucible is theoretically controlled autonomously to an oxygen partial pressure in which only rare earth elements are oxidized without oxidizing iron group elements. However, it is actually necessary to artificially control the inside of the crucible to an atmosphere having an oxygen-containing concentration of 1 ppm or more. Such control can be performed by introducing an inert gas having an oxygen-containing concentration of 1 ppm or more into the crucible as described in Patent Document 2, but argon is widely used as an industrial inert gas. In the case of gas, the oxygen concentration is usually 0.5 ppm or less. Therefore, in order to introduce an argon gas having an oxygen-containing concentration of 1 ppm or more into the crucible, a general-purpose argon gas cannot be used as it is, and it is necessary to increase the oxygen-containing concentration. As a result, although the method described in Patent Document 2 seems to be simple at first glance, it is not so, and like the method described in Patent Document 1, it is put to practical use as a recycling system that requires low cost and simplicity. It must be said that it has difficult aspects.
そこで本発明は、低コストで簡易なリサイクルシステムとして実用化が可能な、少なくとも希土類元素と鉄族元素を含む処理対象物から希土類元素を回収する方法を提供することを目的とする。 Therefore, an object of the present invention is to provide a method for recovering a rare earth element from a processing object containing at least a rare earth element and an iron group element, which can be put into practical use as a simple recycling system at a low cost.
本発明者らは上記の点に鑑みて鋭意検討を重ねた結果、Ｒ−Ｆｅ−Ｂ系永久磁石に対して酸化処理を行った後、処理環境を炭素の存在下に移して１３００℃以上の温度で熱処理することで得られる熱処理物は、水と反応させると崩壊し、崩壊後に希土類元素を含む粉末を回収することができることを見出した。 As a result of intensive studies in view of the above points, the present inventors have performed an oxidation treatment on the R—Fe—B permanent magnet, and then moved the treatment environment to the presence of carbon to be 1300 ° C. or higher. It has been found that a heat-treated product obtained by heat treatment at a temperature collapses when reacted with water, and a powder containing a rare earth element can be recovered after the collapse.
上記の知見に基づいてなされた本発明の少なくとも希土類元素と鉄族元素を含む処理対象物から希土類元素を回収する方法は、請求項１記載の通り、処理対象物に対して酸化処理を行って処理対象物に含まれる酸素モル濃度を希土類元素のモル濃度の１．５倍以上とした後、処理環境を炭素の存在下に移して１４５０℃以上の温度で熱処理し、得られた熱処理物を水と反応させ、希土類元素を含む粉末を回収する工程を少なくとも含んでなることを特徴とする。
また、請求項２記載の方法は、請求項１記載の方法において、酸化処理を行った処理対象物の炭素の存在下での熱処理を、炭素るつぼを処理容器および炭素供給源として用いて行うことを特徴とする。
また、請求項３記載の方法は、請求項１記載の方法において、処理対象物の少なくとも一部が５００μｍ以下の粒径を有する粒状ないし粉末状であることを特徴とする。
また、請求項４記載の方法は、請求項１記載の方法において、熱処理物と水の反応を、熱処理物を空気中に放置して空気中の水と反応させることで行うことを特徴とする。
また、請求項５記載の方法は、請求項１記載の方法において、希土類元素を含む粉末が希土類元素を５０ｍａｓｓ％以上含むことを特徴とする。
また、請求項６記載の方法は、請求項１記載の方法において、希土類元素を含む粉末の粒径が１２０μｍ未満であることを特徴とする。
また、請求項７記載の方法は、請求項１記載の方法において、処理対象物がＲ−Ｆｅ−Ｂ系永久磁石であることを特徴とする。
Method for recovering rare earth elements from a processing object including at least a rare-earth element, iron group element of the present invention made based on the above findings, as claimed in claim 1, wherein, by performing an oxidation process on the processing object After the molar concentration of oxygen contained in the object to be treated is 1.5 times or more of the molar concentration of the rare earth element , the treatment environment is transferred to the presence of carbon and heat treated at a temperature of 1450 ° C. or higher. It is characterized by comprising at least a step of reacting with water and collecting a powder containing a rare earth element.
The method according to claim 2 is the method according to claim 1, wherein the heat treatment in the presence of carbon of the object to be oxidized is performed using a carbon crucible as a processing vessel and a carbon supply source. It is characterized by.
The method according to claim 3 is the method according to claim 1, characterized in that at least a part of the object to be treated is in the form of particles or powder having a particle size of 500 μm or less.
The method according to claim 4 is characterized in that, in the method according to claim 1, the heat-treated product and water are reacted by leaving the heat-treated product in air and reacting with water in the air. .
The method according to claim 5 is characterized in that, in the method according to claim 1, the rare earth element-containing powder contains 50 mass% or more of the rare earth element.
A method according to claim 6 is characterized in that, in the method according to claim 1, the particle size of the powder containing the rare earth element is less than 120 μm.
The method according to claim 7 is the method according to claim 1, wherein the object to be treated is an R-Fe-B permanent magnet.
本発明の方法によれば、少なくとも希土類元素と鉄族元素を含む処理対象物に対して酸化処理を行った後、処理環境を炭素の存在下に移して１３００℃以上の温度で熱処理することで得られる熱処理物を水と反応させるだけで希土類元素を含む粉末を回収することができる。従って、本発明の方法は、低コストで簡易なリサイクルシステムとして実用化が可能な方法である。 According to the method of the present invention, after an oxidation treatment is performed on an object to be treated containing at least a rare earth element and an iron group element, the treatment environment is moved to the presence of carbon and heat treatment is performed at a temperature of 1300 ° C. or higher. Powders containing rare earth elements can be recovered simply by reacting the heat-treated product with water. Therefore, the method of the present invention can be put into practical use as a simple recycling system at a low cost.
本発明の少なくとも希土類元素と鉄族元素を含む処理対象物から希土類元素を回収する方法は、処理対象物に対して酸化処理を行った後、処理環境を炭素の存在下に移して１３００℃以上の温度で熱処理し、得られた熱処理物を水と反応させ、希土類元素を含む粉末を回収する工程を少なくとも含んでなることを特徴とするものである。 In the method of recovering rare earth elements from a processing object containing at least a rare earth element and an iron group element according to the present invention, after oxidizing the processing object, the processing environment is transferred to the presence of carbon and 1300 ° C. or higher. At least a step of reacting the obtained heat-treated product with water and recovering the powder containing the rare earth element.
本発明の方法の適用対象となる少なくとも希土類元素と鉄族元素を含む処理対象物は、Ｎｄ，Ｐｒ，Ｄｙ，Ｔｂ，Ｓｍなどの希土類元素とＦｅ，Ｃｏ，Ｎｉなどの鉄族元素を含むものであれば特段の制限はなく、希土類元素と鉄族元素に加えてその他の元素として例えばホウ素などを含んでいてもよい。具体的には、例えばＲ−Ｆｅ−Ｂ系永久磁石などが挙げられるが、とりわけ本発明の方法は鉄族元素含量が３０ｍａｓｓ％以上である処理対象物に好適に適用することができる（例えばＲ−Ｆｅ−Ｂ系永久磁石の場合、その鉄族元素含量は、通常、６０ｍａｓｓ％〜８２ｍａｓｓ％である）。処理対象物の大きさや形状は特段制限されるものではなく、処理対象物がＲ−Ｆｅ−Ｂ系永久磁石の場合には製造工程中に排出される磁石スクラップや磁石加工屑などであってよい。処理対象物に対して十分な酸化処理を行うためには、処理対象物は５００μｍ以下の粒径を有する粒状ないし粉末状であることが望ましい（例えば調製の容易性に鑑みれば粒径の下限は１μｍが望ましい）。しかしながら、処理対象物の全てがこのような粒状ないし粉末状である必要は必ずしもなく、粒状ないし粉末状であるのは処理対象物の一部であってよい。 The processing object containing at least a rare earth element and an iron group element to which the method of the present invention is applied contains a rare earth element such as Nd, Pr, Dy, Tb, and Sm and an iron group element such as Fe, Co, and Ni. If so, there is no particular limitation, and in addition to the rare earth element and the iron group element, other elements such as boron may be included. Specifically, for example, R-Fe-B permanent magnets and the like can be mentioned, and in particular, the method of the present invention can be suitably applied to a processing object having an iron group element content of 30 mass% or more (for example, R In the case of a -Fe-B permanent magnet, the iron group element content is usually 60 mass% to 82 mass%). The size and shape of the object to be processed are not particularly limited. When the object to be processed is an R-Fe-B permanent magnet, it may be magnet scrap or magnet processing waste discharged during the manufacturing process. . In order to perform sufficient oxidation treatment on the object to be treated, it is desirable that the object to be treated is granular or powdery having a particle size of 500 μm or less (for example, considering the ease of preparation, the lower limit of the particle size is 1 μm is desirable). However, it is not always necessary that the object to be processed is in such a granular or powder form, and it may be a part of the object to be processed.
まず、本発明の方法における処理対象物に対する酸化処理は、処理対象物に含まれる希土類元素を酸化物に変換することを目的とするものである。特許文献２に記載の方法と異なり、処理対象物に対する酸化処理によって処理対象物に含まれる鉄族元素が希土類元素とともに酸化物に変換されてもよい。処理対象物に対する酸化処理は、酸素含有雰囲気中で処理対象物を熱処理したり燃焼処理したりすることによって行うことが簡便である。酸素含有雰囲気は大気雰囲気であってよい。処理対象物を熱処理する場合、例えば３５０℃〜１０００℃で１時間〜５時間行えばよい。処理対象物を燃焼処理する場合、例えば自然発火や人為的点火により行えばよい。また、処理対象物に対する酸化処理は、アルカリ水溶液中で処理対象物の酸化を進行させるアルカリ処理によって行うこともできる。アルカリ処理に用いることができるアルカリとしては水酸化ナトリウム、水酸化カリウム、炭酸水素ナトリウム、炭酸ナトリウム、アンモニアなどが挙げられる。また、アルカリ水溶液の濃度としては０．１ｍｏｌ／Ｌ〜１０ｍｏｌ／Ｌが挙げられる。処理温度としては６０℃〜１５０℃が挙げられるが、より効果的な酸化処理を行うためには１００℃以上が望ましく、より安全性を高めるためには１３０℃以下が望ましい。処理時間としては３０分間〜１０時間が挙げられる。処理対象物に対する酸化処理は、単一の方法で行ってもよいし、複数の方法を組み合わせて行ってもよい。処理対象物に対してこうした酸化処理を行うと、処理対象物に含まれる酸素モル濃度は希土類元素のモル濃度の１．５倍以上となり、希土類元素の酸化物への変換をより確実なものにすることができる。酸化処理によって処理対象物に含まれる酸素モル濃度は希土類元素のモル濃度の２．０倍以上になることが望ましい。また、処理対象物に対する酸化処理は、炭素の非存在下で行うことが望ましい。炭素の存在下で処理対象物に対する酸化処理を行うと、処理対象物に含まれる希土類元素が炭素と望まざる化学反応を起こして所望する酸化物への変換が阻害される恐れがあるからである（従ってここでは「炭素の非存在下」は処理対象物に含まれる希土類元素の酸化物への変換が阻害されるに足る化学反応の起因となる炭素が存在しないことを意味する）。 First, the oxidation treatment on the object to be treated in the method of the present invention aims to convert the rare earth element contained in the object to be treated into an oxide. Unlike the method described in Patent Document 2, the iron group element contained in the processing object may be converted into an oxide together with the rare earth element by the oxidation treatment on the processing object. It is simple to perform the oxidation treatment on the object to be treated by heat-treating or burning the object to be treated in an oxygen-containing atmosphere. The oxygen-containing atmosphere may be an air atmosphere. What is necessary is just to perform 1 to 5 hours, for example at 350 to 1000 degreeC, when heat-treating a process target object. When the object to be processed is subjected to combustion processing, for example, spontaneous ignition or artificial ignition may be performed. Moreover, the oxidation process with respect to a process target object can also be performed by the alkali process which advances the oxidation of a process target object in alkaline aqueous solution. Examples of the alkali that can be used for the alkali treatment include sodium hydroxide, potassium hydroxide, sodium hydrogen carbonate, sodium carbonate, and ammonia. Moreover, 0.1 mol / L-10 mol / L are mentioned as a density | concentration of aqueous alkali solution. The processing temperature may be 60 ° C. to 150 ° C., but it is preferably 100 ° C. or higher for more effective oxidation treatment, and 130 ° C. or lower for higher safety. As processing time, 30 minutes-10 hours are mentioned. The oxidation treatment on the object to be treated may be performed by a single method or a combination of a plurality of methods. When such an oxidation treatment is performed on the object to be treated, the molar concentration of oxygen contained in the object to be treated is 1.5 times or more the molar concentration of the rare earth element, and the conversion of the rare earth element to the oxide is more reliable. can do. It is desirable that the molar concentration of oxygen contained in the object to be treated by the oxidation treatment is 2.0 times or more that of the rare earth element. Moreover, it is desirable to perform the oxidation treatment on the object to be treated in the absence of carbon. This is because when the oxidation treatment is performed on the object to be treated in the presence of carbon, the rare earth element contained in the object to be treated may cause an undesired chemical reaction with carbon and inhibit the conversion to a desired oxide. (Thus, “in the absence of carbon” here means that there is no carbon that causes a chemical reaction sufficient to inhibit the conversion of the rare earth element contained in the object to be processed into an oxide).
次に、酸化処理を行った処理対象物を炭素の存在下に移して１３００℃以上の温度で熱処理する。熱処理温度を１３００℃以上に規定するのは、１３００℃未満であると、処理対象物からの希土類元素の回収を効果的に行えない恐れがあるからである。熱処理温度は１３５０℃以上が望ましく、１４００℃以上がより望ましく、１４５０℃以上がさらに望ましい。熱処理温度の上限は、過度の高温による処理設備への悪影響の回避などに鑑みれば２３００℃が望ましく、２１００℃がより望ましい。熱処理時間は例えば１０分間〜３時間が適当である。酸化処理を行った処理対象物に対する炭素の供給源は、グラファイト（黒鉛や石墨）、木炭、コークス、石炭、ダイヤモンド、カーボンブラックなど、どのような構造や形状のものであってもよいが、炭素るつぼを用いて熱処理を行えば、炭素るつぼは処理容器としての役割とともにその表面からの炭素供給源としての役割も果たすので都合がよい（もちろん別個の炭素供給源をさらに添加することを妨げるものではない）。処理容器として炭素るつぼを用いる場合、酸化処理を行った処理対象物の炭素の存在下での熱処理は、アルゴンガス雰囲気などの不活性ガス雰囲気（酸素含有濃度は１ｐｐｍ未満が望ましい）中や真空（１０００Ｐａ未満が望ましい）中で行うことが望ましい。大気雰囲気などの酸素含有雰囲気中で熱処理を行うと、雰囲気中の酸素が炭素るつぼの表面において炭素と反応することで二酸化炭素を生成し、炭素るつぼが炭素供給源としての役割を効率的に果さない恐れがあるからである。なお、用いることができる処理容器は、特許文献２に記載の方法のように炭素るつぼに限定されるわけではなく、非炭素製の処理容器、例えばアルミナや酸化マグネシウムや酸化カルシウムなどの金属酸化物や酸化ケイ素でできたセラミックスるつぼ（単一の素材からなるものであってもよいし複数の素材からなるものであってもよい。炭化ケイ素などの炭素元素を含む素材であっても炭素供給源としての役割を果さない素材からなるものを含む）などを用いることもできる。非炭素製の処理容器を用いる場合、処理容器は炭素供給源としての役割を果さないので、処理容器に炭素供給源を添加することによって酸化処理を行った処理対象物を熱処理する。また、非炭素製の処理容器として製鉄のための溶鉱炉、電気炉、誘導炉などを用いるとともに、炭素供給源として木炭やコークスなどを用いれば、酸化処理を行った処理対象物を一度に大量に熱処理することができる。添加する炭素供給源の量は処理対象物に含まれる鉄族元素に対してモル比で１．５倍以上であることが望ましい。添加する炭素供給源の量をこのように調整することで、処理対象物に含まれる鉄族元素が酸化処理によって酸化物に変換されてもその還元を確実なものとして炭素との合金化を進行させることができる。なお、非炭素製の処理容器を用いる場合、酸化処理を行った処理対象物の炭素の存在下での熱処理は、アルゴンガス雰囲気などの不活性ガス雰囲気（酸素含有濃度は１ｐｐｍ未満が望ましい）中や真空（１０００Ｐａ未満が望ましい）中で行ってもよいし、大気雰囲気などの酸素含有雰囲気中で行ってもよい。酸化処理を行った処理対象物の炭素の存在下での熱処理を酸素含有雰囲気中で行った場合、熱処理後における処理容器内の余剰の炭素供給源は雰囲気中の酸素と反応することによって二酸化炭素となって処理容器から排出される点において都合がよい。 Next, the object to be treated that has undergone the oxidation treatment is transferred to the presence of carbon and heat treated at a temperature of 1300 ° C. or higher. The reason why the heat treatment temperature is set to 1300 ° C. or more is that if it is less than 1300 ° C., there is a possibility that the rare earth element cannot be effectively recovered from the object to be treated. The heat treatment temperature is preferably 1350 ° C. or higher, more preferably 1400 ° C. or higher, and further preferably 1450 ° C. or higher. The upper limit of the heat treatment temperature is preferably 2300 ° C. and more preferably 2100 ° C. in view of avoiding adverse effects on the processing equipment due to excessively high temperatures. The heat treatment time is suitably 10 minutes to 3 hours, for example. The carbon supply source for the object to be treated may be of any structure or shape, such as graphite (graphite or graphite), charcoal, coke, coal, diamond, carbon black, etc. When a heat treatment is performed using a crucible, the carbon crucible serves not only as a processing vessel but also as a carbon source from its surface (of course, it does not prevent the addition of a separate carbon source). Absent). When a carbon crucible is used as a processing container, the heat treatment in the presence of carbon of the object to be oxidized is performed in an inert gas atmosphere such as an argon gas atmosphere (the oxygen-containing concentration is preferably less than 1 ppm) or in a vacuum ( It is desirable to carry out in less than 1000 Pa). When heat treatment is performed in an oxygen-containing atmosphere such as the air atmosphere, carbon in the atmosphere reacts with carbon on the surface of the carbon crucible to generate carbon dioxide, and the carbon crucible efficiently plays a role as a carbon supply source. Because there is a fear of not. The processing container that can be used is not limited to a carbon crucible as in the method described in Patent Document 2, but a non-carbon processing container, for example, a metal oxide such as alumina, magnesium oxide, or calcium oxide. Or ceramic crucible made of silicon oxide (may be composed of a single material or may be composed of a plurality of materials. Even if it is a material containing a carbon element such as silicon carbide, it is a carbon source. (Including materials made of materials that do not play a role). In the case of using a non-carbon processing container, the processing container does not serve as a carbon supply source. Therefore, the processing object subjected to the oxidation treatment is heat-treated by adding the carbon supply source to the processing container. In addition, using a blast furnace, electric furnace, induction furnace, etc. for iron making as a non-carbon treatment container, and using charcoal, coke, etc. as a carbon supply source, a large amount of the treatment object subjected to oxidation treatment can be obtained at once. It can be heat treated. The amount of the carbon source to be added is desirably 1.5 times or more in terms of molar ratio with respect to the iron group element contained in the object to be treated. By adjusting the amount of carbon source to be added in this way, even if iron group elements contained in the object to be processed are converted into oxides by oxidation treatment, the reduction is ensured and alloying with carbon proceeds. Can be made. When a non-carbon processing vessel is used, the heat treatment in the presence of carbon of the object to be oxidized is performed in an inert gas atmosphere such as an argon gas atmosphere (the oxygen-containing concentration is preferably less than 1 ppm). Or in a vacuum (less than 1000 Pa is desirable) or in an oxygen-containing atmosphere such as an air atmosphere. When the heat treatment in the presence of carbon of the object to be oxidized is performed in an oxygen-containing atmosphere, the excess carbon supply source in the treatment container after the heat treatment reacts with oxygen in the atmosphere to generate carbon dioxide. This is convenient in that it is discharged from the processing container.
こうして炭素の存在下で熱処理することで得られる熱処理物は、処理容器内に２種類の塊状物として存在したり、処理容器内に単一の塊状物として存在したりする。こうした熱処理物の形態の違いは、本発明者らの検討によれば、処理対象物に対する酸化処理の方法の違いや酸化処理を行った処理対象物に対する熱処理の方法の違い、処理対象物が希土類元素と鉄族元素以外にその他の元素を含むか否かの違いなどに起因すると推察される。一例を挙げると、処理対象物がＲ−Ｆｅ−Ｂ系永久磁石などのようにその他の元素としてホウ素を含む場合、例えば、処理対象物に対する酸化処理を酸素含有雰囲気中で処理対象物を熱処理したり燃焼処理したりすることで行うと、熱処理物は処理容器内に２種類の塊状物として存在する傾向にある一方、処理対象物に対する酸化処理をアルカリ処理によって行うと、熱処理物は処理容器内に単一の塊状物として存在する傾向にある。また、例えば、酸化処理を行った処理対象物を粒径の小さい（例えば１２５μｍ未満）炭素供給源と混合してから炭素るつぼを用いて熱処理すると、熱処理物は炭素るつぼ内に単一の塊状物として存在する傾向にある。熱処理物が２種類の塊状物として得られる場合、熱処理物を水と反応させることで２種類の塊状物のうちの一方が、熱処理物が単一の塊状物として得られる場合、熱処理物を水と反応させることで熱処理物の全部または一部が、特別な人為的操作を行わなくても自然に崩壊し、崩壊後に希土類元素を含む粉末を回収することができる。熱処理物と水を反応させる方法は特段限定されるものではなく、熱処理物を水中に浸漬して反応させる方法などであってもよいが、熱処理物を空気中に放置して空気中の水と反応させる方法が簡便であって望ましい。熱処理物と反応させる水は酸性水やアルカリ性水であってもよい。また、熱処理物と水を反応させる環境を高温にしたり、高湿度にしたり、高圧にしたりする方法も有効である。熱処理物と水を反応させる時間（熱処理物が崩壊するに至るまでの時間）は処理量などにもよるが、例えば５分間〜１０日間である（熱処理物を空気中に放置して空気中の水と反応させる方法の場合にはそれ以上の時間、例えば１年間といった長期間であってもよい）。 The heat-treated product obtained by heat treatment in the presence of carbon thus exists as two types of lumps in the processing container or as a single lumps in the processing container. According to the study by the present inventors, such a difference in the form of the heat treatment product is due to the difference in the oxidation treatment method for the treatment object, the difference in the heat treatment method for the treatment object subjected to the oxidation treatment, and the treatment object is rare earth. It is presumed to be due to the difference in whether or not other elements are included in addition to elements and iron group elements. For example, when the object to be treated contains boron as another element such as an R—Fe—B permanent magnet, for example, the object to be treated is heat-treated in an oxygen-containing atmosphere. When the heat treatment product tends to exist as two kinds of lumps in the treatment container, the heat treatment product is treated in the treatment container when the oxidation treatment is performed by alkali treatment. Tend to exist as a single mass. Also, for example, when the object to be treated is mixed with a carbon source having a small particle size (for example, less than 125 μm) and then heat-treated using a carbon crucible, the heat-treated product is a single lump in the carbon crucible. Tend to exist as. When the heat-treated product is obtained as two types of lumps, when one of the two types of lumps is obtained by reacting the heat-treated product with water, the heat-treated product is obtained as water. , The whole or a part of the heat-treated product can be naturally collapsed without any special artificial operation, and the powder containing the rare earth element can be recovered after the collapse. The method of reacting the heat-treated product with water is not particularly limited, and may be a method of reacting the heat-treated product by immersing it in water. The method of reacting is simple and desirable. The water to be reacted with the heat-treated product may be acidic water or alkaline water. It is also effective to increase the environment in which the heat-treated product and water react with each other at a high temperature, high humidity, or high pressure. The time for reacting the heat-treated product with water (the time until the heat-treated product collapses) depends on the amount of treatment, but is, for example, 5 minutes to 10 days (the heat-treated product is left in the air and left in the air. In the case of the method of reacting with water, it may be a longer time such as one year).
回収された希土類元素を含む粉末は、好適には希土類元素を５０ｍａｓｓ％以上（６０ｍａｓｓ％以上が望ましく７０ｍａｓｓ％以上がより望ましい）含み、その粒径は１２０μｍ未満である。前述の通り、処理対象物がＲ−Ｆｅ−Ｂ系永久磁石などのようにその他の元素としてホウ素を含む場合、例えば、処理対象物に対する酸化処理を酸素含有雰囲気中で処理対象物を熱処理したり燃焼処理したりすることで行うと、熱処理物は処理容器内に２種類の塊状物として存在し、そのうちの一方の塊状物が水と反応することで崩壊して希土類元素を含む粉末となる傾向にある。他方の塊状物は塊状のままであるので、崩壊後に例えば目開きが１２０μｍの篩にかけることで、希土類元素を含む粉末を他方の塊状物と分離して回収することができる。また、例えば、処理対象物に対する酸化処理をアルカリ処理によって行ったり、酸化処理を行った処理対象物を粒径の小さい（例えば１２５μｍ未満）炭素供給源と混合してから炭素るつぼを用いて熱処理したりすると、熱処理物は処理容器内に単一の塊状物として存在し、この塊状物は水と反応することで全部または一部が崩壊する傾向にある。崩壊後には大きさが異なる２種類の粉末が存在したり、崩壊しなかった塊状物と粉末が存在したりし、希土類元素を含む粉末は前者の場合は大きさの小さい方の粉末として得られ、後者の場合は崩壊した粉末として得られる。従って、例えば目開きが１２０μｍの篩にかけることで、希土類元素を含む粉末を大きさの大きい方の粉末や崩壊しなかった塊状物と分離して回収することができる。こうした現象は、酸化処理を行った処理対象物に含まれる希土類元素の酸化物が炭素の存在下での熱処理によって安定性に劣る炭化物に変換され、熱処理物に含まれるこの炭化物が水と反応することで水酸化物に変換される一方で、鉄族元素は炭素の存在下での熱処理によって炭素を固溶して合金化して溶融し、また、鉄族元素の酸化物は炭素によって還元された後に炭素を固溶して合金化して溶融し、結果として、鉄族元素と炭素の合金の溶融物が生成するが、この溶融物は安定性が高いため水と反応しないことに起因すると推察される。処理対象物に対する酸化処理を酸素含有雰囲気中で処理対象物を熱処理したり燃焼処理したりすることで行った場合における熱処理物を水と反応させた後に塊状のままである塊状物と、処理対象物に対する酸化処理をアルカリ処理によって行ったり、酸化処理を行った処理対象物を粒径の小さい（例えば１２５μｍ未満）炭素供給源と混合してから炭素るつぼを用いて熱処理したりした場合における熱処理物を水と反応させた後に得られる大きさの大きい方の粉末や崩壊しなかった塊状物は、いずれも鉄族元素を通常７０ｍａｓｓ％以上含む。なお、希土類元素を含む粉末の鉄族元素の含有量は、通常２５ｍａｓｓ％以下である。従って、希土類元素を含む粉末と鉄族元素を主成分とする塊状物や粉末の分離には磁選も有効である（希土類元素を含む粉末は磁石に吸引されない）。処理対象物がＲ−Ｆｅ−Ｂ系永久磁石などのようにその他の元素としてホウ素を含む場合における、処理対象物に対する酸化処理の方法の違いによる熱処理物の形態の違いは、酸化処理を行った処理対象物のホウ素の含有量の違いに起因すると推察される。処理対象物に対する酸化処理を酸素含有雰囲気中で処理対象物を熱処理したり燃焼処理したりすることで行った場合、酸化処理を行った処理対象物のホウ素含量は通常０．７ｍａｓｓ％以上である。一方、処理対象物に対する酸化処理をアルカリ処理によって行った場合、アルカリ処理によって処理対象物のホウ素含量が低減され、酸化処理を行った処理対象物のホウ素含量は通常０．４ｍａｓｓ％以下である。いずれの場合においても本発明の方法によって希土類元素を含む粉末を得ることができるが、本発明の方法においては、酸化処理を行った処理対象物のホウ素含量は少ない方が望ましく（例えば２．０ｍａｓｓ％以下）、酸化処理を行った処理対象物のホウ素含量が少ないことで、ホウ素モル濃度が希土類元素のモル濃度の例えば０．３５倍以下といった希土類元素のモル濃度に対するホウ素モル濃度が小さい希土類元素を含む粉末を得やすくなるようである。 The recovered powder containing rare earth elements preferably contains 50 mass% or more (preferably 60 mass% or more, more preferably 70 mass% or more) of rare earth elements, and the particle size thereof is less than 120 μm. As described above, when the object to be treated includes boron as another element such as an R—Fe—B permanent magnet, for example, the object to be treated is subjected to an oxidation treatment in an oxygen-containing atmosphere by heat treatment. When it is performed by burning treatment, the heat-treated product exists as two kinds of lumps in the processing container, and one of the lumps tends to collapse by reacting with water to become a powder containing rare earth elements. It is in. Since the other lump remains lump, the powder containing the rare earth element can be separated and collected from the other lump by, for example, passing through a sieve having an opening of 120 μm after the collapse. Further, for example, the oxidation treatment on the object to be treated is performed by alkali treatment, or the object to be treated is mixed with a carbon source having a small particle size (for example, less than 125 μm) and then heat-treated using a carbon crucible. In other words, the heat-treated product exists as a single lump in the processing container, and this lump tends to be wholly or partially collapsed by reacting with water. After disintegration, there are two types of powders with different sizes, or there are lumps and powders that did not disintegrate. In the former case, the powder containing rare earth elements is obtained as the smaller size powder. In the latter case, it is obtained as a disintegrated powder. Therefore, for example, by passing through a sieve having an opening of 120 μm, the powder containing the rare earth element can be separated and recovered from the larger powder and the lump that has not collapsed. Such a phenomenon is caused by the fact that the rare earth element oxide contained in the object to be treated that has undergone the oxidation treatment is converted to a poorly stable carbide by the heat treatment in the presence of carbon, and this carbide contained in the heat treated product reacts with water. On the other hand, the iron group element was melted by solid solution of the carbon by the heat treatment in the presence of carbon, and the iron group element oxide was reduced by the carbon. Later, carbon was dissolved and alloyed and melted. As a result, a melt of an alloy of an iron group element and carbon was formed, which is presumed to be caused by the fact that this melt is highly stable and does not react with water. The A lump that remains in a lump after reacting the heat-treated product with water when the treatment is performed by subjecting the treatment target to heat treatment or combustion treatment in an oxygen-containing atmosphere. Heat treatment product in the case where an oxidation treatment is performed on an object by an alkali treatment, or a treatment object subjected to the oxidation treatment is mixed with a carbon source having a small particle size (for example, less than 125 μm) and then heat treated using a carbon crucible The larger powder obtained after reacting with water and the lump that did not disintegrate usually contain 70 mass% or more of an iron group element. In addition, the content of the iron group element in the powder containing the rare earth element is usually 25 mass% or less. Therefore, magnetic separation is also effective for separating a lump containing rare earth elements and a lump or powder mainly composed of an iron group element (powder containing rare earth elements is not attracted by a magnet). When the object to be treated contains boron as another element such as an R-Fe-B permanent magnet, the difference in the form of the heat-treated material due to the difference in the method of oxidation treatment with respect to the object to be treated was subjected to the oxidation treatment. It is inferred to be due to the difference in the boron content of the object to be treated. When the oxidation treatment is performed on the treatment object by heat-treating or burning the treatment object in an oxygen-containing atmosphere, the boron content of the treatment object subjected to the oxidation treatment is usually 0.7 mass% or more. . On the other hand, when the oxidation treatment is performed on the object to be treated by alkali treatment, the boron content of the object to be treated is reduced by the alkali treatment, and the boron content of the object to be treated subjected to the oxidation treatment is usually 0.4 mass% or less. In any case, a powder containing a rare earth element can be obtained by the method of the present invention. However, in the method of the present invention, it is desirable that the boron content of the object to be treated is low (for example, 2.0 mass). Rare earth elements having a low boron molar concentration relative to the molar concentration of rare earth elements such as 0.35 times the molar concentration of rare earth elements, for example, 0.35 times the molar concentration of rare earth elements or less. It seems to be easy to obtain a powder containing.
本発明の方法によって回収される希土類元素を含む粉末に含まれる希土類元素は水酸化物として存在するので、熱処理や燃焼処理などによる脱水処理をしてから例えば溶融塩電解法などによって還元することで希土類金属に変換することができる。処理対象物が例えばＲ−Ｆｅ−Ｂ系永久磁石などのように希土類元素と鉄族元素に加えてその他の元素としてホウ素を含む場合、本発明の方法によって回収される希土類元素を含む粉末には上記の通りホウ素が多少なりとも含まれる。希土類元素に加えてホウ素を含む粉末をフッ素を含む溶融塩成分を用いた溶融塩電解法によって還元すると、ホウ素がフッ素と反応することで有毒なフッ化ホウ素が発生する恐れがある。従って、希土類元素を含む粉末のホウ素含量が多い場合（例えば２．３ｍａｓｓ％以上の場合）にはホウ素含量を低減しておくことが望ましい。希土類元素を含む粉末のホウ素含量の低減は、例えば希土類元素を含む粉末をアルカリ金属の炭酸塩（炭酸リチウム、炭酸ナトリウム、炭酸カリウムなど）や酸化物とともに例えば炭素の存在下で熱処理することで行うことができる。炭素の存在下での熱処理は、例えばグラファイト（黒鉛や石墨）、木炭、コークス、石炭、ダイヤモンド、カーボンブラックなどを炭素の供給源として用いて１３００℃〜１６００℃で行えばよい。熱処理時間は例えば３０分間〜５時間が適当である。炭素るつぼを用いて熱処理を行えば、炭素るつぼは処理容器としての役割とともにその表面からの炭素供給源としての役割も果たすので都合がよい（もちろん別個の炭素供給源をさらに添加することを妨げるものではない）。アルカリ金属の炭酸塩や酸化物は、例えば希土類元素を含む粉末１重量部に対して０．１重量部〜２重量部用いればよい。 Since the rare earth element contained in the powder containing the rare earth element recovered by the method of the present invention exists as a hydroxide, it is reduced by, for example, a molten salt electrolysis method after dehydration by heat treatment or combustion treatment. Can be converted to rare earth metals. When the object to be treated contains boron as another element in addition to a rare earth element and an iron group element such as an R-Fe-B permanent magnet, the powder containing the rare earth element recovered by the method of the present invention includes As mentioned above, boron is included to some extent. When a powder containing boron in addition to a rare earth element is reduced by a molten salt electrolysis method using a molten salt component containing fluorine, toxic boron fluoride may be generated by reacting boron with fluorine. Therefore, when the boron content of the rare earth element-containing powder is large (for example, 2.3 mass% or more), it is desirable to reduce the boron content. The boron content of the powder containing rare earth elements is reduced by, for example, heat-treating the powder containing rare earth elements together with alkali metal carbonate (lithium carbonate, sodium carbonate, potassium carbonate, etc.) or oxide in the presence of carbon, for example. be able to. The heat treatment in the presence of carbon may be performed at 1300 ° C. to 1600 ° C. using graphite (graphite or graphite), charcoal, coke, coal, diamond, carbon black, or the like as a carbon supply source. The heat treatment time is suitably, for example, 30 minutes to 5 hours. Heat treatment using a carbon crucible is advantageous because the carbon crucible serves as a carbon source from the surface as well as a treatment vessel (of course preventing further addition of a separate carbon source) is not). The alkali metal carbonate or oxide may be used, for example, in an amount of 0.1 to 2 parts by weight with respect to 1 part by weight of the powder containing the rare earth element.
以下、本発明を実施例によって詳細に説明するが、本発明は以下の記載に限定して解釈されるものではない。 EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is limited to the following description and is not interpreted.
実施例１：
Ｒ−Ｆｅ−Ｂ系永久磁石の製造工程中に発生した約１０μｍの粒径を有する磁石加工屑（自然発火防止のため水中で７日間保管したもの）に対し、吸引ろ過することで脱水してから大気雰囲気中で火をつけて燃焼処理を行うことで酸化処理を行った。こうして酸化処理を行った磁石加工屑のＩＣＰ分析結果（使用装置：島津製作所社製のＩＣＰＶ−１０１７、以下同じ）とガス分析結果（使用装置：堀場製作所社製のＥＭＧＡ−５５０Ｗ、以下同じ）を表１に示す。酸化処理を行った磁石加工屑に含まれる酸素モル濃度は希土類元素のモル濃度の７．６倍であった。
Example 1:
Magnet processed scraps (stored in water for 7 days to prevent spontaneous ignition) generated during the manufacturing process of R-Fe-B permanent magnets are dehydrated by suction filtration. Oxidation treatment was performed by igniting fire in the atmosphere and performing combustion treatment. The ICP analysis results of the magnet processing scraps thus oxidized (use apparatus: ICPV-1017 manufactured by Shimadzu Corporation, and the same below) and the gas analysis results (use apparatus: EMGA-550W manufactured by Horiba, Ltd., and the same below). Table 1 shows. The oxygen molar concentration contained in the magnet processing waste subjected to the oxidation treatment was 7.6 times the molar concentration of the rare earth element.
次に、酸化処理を行った磁石加工屑５０ｇを、寸法が外径７０ｍｍ×高さ７０ｍｍ×肉厚１０ｍｍの炭素るつぼ（黒鉛製）に収容した後、工業用アルゴンガス雰囲気（酸素含有濃度：０．２ｐｐｍ、流量：１０Ｌ／分。以下同じ）中で１８００℃で１時間熱処理した。その後、炭素るつぼを室温まで炉冷したところ、炭素るつぼ内には熱処理物として２種類の塊状物（塊状物Ａと塊状物Ｂ）がるつぼに固着して存在した（図１−１）。この２種類の塊状物は、空気中で１日間放置しておくと、塊状物Ａは塊状のままであるのに対し、塊状物Ｂはアセチレン臭を発しながら自然に崩壊して粉末となり（図１−２）、炭素るつぼの内容物を目開きが１２０μｍの篩にかけることで粉末のみを回収することができた（図１−３）。篩にかけた後の塊状物Ａと回収された塊状物Ｂ由来の粉末のそれぞれのＩＣＰ分析結果とガス分析結果を表２に示す。表２から明らかなように、塊状物Ａの主成分は鉄である一方、塊状物Ｂの主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、塊状物Ｂ由来の粉末のホウ素モル濃度は希土類元素のモル濃度の０．０７倍であった。また、塊状物Ｂ由来の粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。 Next, 50 g of magnetized scraps subjected to the oxidation treatment were placed in a carbon crucible (made of graphite) having dimensions of outer diameter 70 mm × height 70 mm × thickness 10 mm, and then an industrial argon gas atmosphere (oxygen-containing concentration: 0). .2 ppm, flow rate: 10 L / min. The same shall apply hereinafter) for 1 hour at 1800 ° C. Then, when the carbon crucible was cooled to room temperature, two types of lumps (lumps A and lumps B) were fixed to the crucible as heat-treated products (FIG. 1-1). When these two types of lumps are left in the air for one day, the lumps A remain in the lumps, whereas the lumps B spontaneously disintegrate into powders while producing an acetylene odor (Fig. 1-2), only the powder could be recovered by passing the contents of the carbon crucible through a sieve having an opening of 120 μm (FIG. 1-3). Table 2 shows the ICP analysis results and gas analysis results of the lump A after sieving and the collected lump B-derived powder. As is apparent from Table 2, the main component of the block A was iron, while the main component of the block B was a rare earth element, and it was found that the rare earth element could be separated from iron as a powder. In addition, the boron molar concentration of the powder derived from the block B was 0.07 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder derived from the block B was a hydroxide of a rare earth element.
実施例２：
酸化処理を行った磁石加工屑を２０００℃で熱処理すること以外は実施例１と同様にして実験を行ったところ、実施例１の場合と同様に、炭素るつぼ内には熱処理物として２種類の塊状物（塊状物Ａと塊状物Ｂ）がるつぼに固着して存在し、この２種類の塊状物は、空気中で１日間放置しておくと、塊状物Ａは塊状のままであるのに対し、塊状物Ｂはアセチレン臭を発しながら自然に崩壊して粉末となり、炭素るつぼの内容物を目開きが１２０μｍの篩にかけることで粉末のみを回収することができた。篩にかけた後の塊状物ＡのＳＥＭ・ＥＤＸ分析結果（使用装置：日立ハイテクノロジーズ社製のＳ８００、以下同じ）と回収された塊状物Ｂ由来の粉末のＩＣＰ分析結果を表３に示す。表３から明らかなように、塊状物Ａの主成分は鉄である一方、塊状物Ｂの主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、塊状物Ｂ由来の粉末のホウ素モル濃度は希土類元素のモル濃度の０．１８倍であった。また、塊状物Ｂ由来の粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 2:
An experiment was conducted in the same manner as in Example 1 except that the magnetized scraps subjected to oxidation treatment were heat-treated at 2000 ° C. As in Example 1, two kinds of heat-treated products were placed in the carbon crucible. A lump (Agglomerate A and lump B) is present on the crucible, and these two types of agglomerates are left in air for 1 day, but the agglomerate A remains agglomerated. On the other hand, the mass B spontaneously disintegrated into a powder while producing an acetylene odor, and only the powder could be recovered by passing the contents of the carbon crucible through a sieve having an opening of 120 μm. Table 3 shows the results of SEM / EDX analysis of the lump A after sieving (device used: S800 manufactured by Hitachi High-Technologies Corporation, the same applies hereinafter) and the ICP analysis result of the recovered powder derived from lump B. As is clear from Table 3, the main component of the block A was iron, while the main component of the block B was a rare earth element, and it was found that the rare earth element could be separated from iron as a powder. The boron molar concentration of the powder derived from the block B was 0.18 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder derived from the block B was a hydroxide of a rare earth element.
実施例３：
Ｒ−Ｆｅ−Ｂ系永久磁石の製造工程中に発生した約１０μｍの粒径を有する磁石加工屑（自然発火防止のため水中で７日間保管したもの）を、１００℃に加熱した５ｍｏｌ／Ｌの水酸化ナトリウム水溶液に１時間浸漬してアルカリ処理を行った。１時間後、吸引濾過してアルカリ処理を行った磁石加工屑を回収し、回収したアルカリ処理を行った磁石加工屑を純水中に投入して撹拌することで洗浄し、吸引濾過してアルカリ処理を行った磁石加工屑を回収した。この操作をあと２回繰り返してアルカリ処理を行った磁石加工屑を十分に水洗した後、１５０℃のホットプレート上で乾燥させた。こうして酸化処理を行った磁石加工屑のＩＣＰ分析結果とガス分析結果の結果を表４に示す。酸化処理を行った磁石加工屑に含まれる酸素モル濃度は希土類元素のモル濃度の９．５倍であった。
Example 3:
5 mol / L of magnet processing waste (stored in water for 7 days to prevent spontaneous ignition) generated at the time of manufacturing the R-Fe-B permanent magnet and having a particle diameter of about 10 μm was heated to 100 ° C. Alkaline treatment was performed by immersing in an aqueous sodium hydroxide solution for 1 hour. After 1 hour, the magnet processing scraps that have been subjected to alkali treatment by suction filtration are collected, and the recovered magnet processing scraps that have been subjected to alkali treatment are washed by being put into pure water and stirred, and then subjected to suction filtration and alkali treatment. The processed magnet processing scrap was collected. This operation was repeated two more times, and the magnet processing scraps that had been subjected to alkali treatment were sufficiently washed with water, and then dried on a hot plate at 150 ° C. Table 4 shows the results of the ICP analysis and the gas analysis of the magnet processing scraps thus oxidized. The oxygen molar concentration contained in the magnet processing waste subjected to the oxidation treatment was 9.5 times the molar concentration of the rare earth element.
次に、酸化処理を行った磁石加工屑５０ｇを、寸法が外径７０ｍｍ×高さ７０ｍｍ×肉厚１０ｍｍの炭素るつぼ（黒鉛製）に収容した後、工業用アルゴンガス雰囲気中で１８００℃で１時間熱処理した。その後、炭素るつぼを室温まで炉冷したところ、炭素るつぼ内には熱処理物として単一の塊状物がるつぼに固着して存在した（図２−１）。この塊状物は、空気中で１日間放置しておくと、アセチレン臭を発しながら自然に崩壊して粉末となり（図２−２）、炭素るつぼの内容物を目開きが１２０μｍの篩にかけることで大きさが異なる２種類の粉末（粉末Ａと粉末Ｂ）を回収することができた（図２−３）。粉末Ａと粉末ＢのそれぞれのＩＣＰ分析結果とガス分析結果を表５に示す。表５から明らかなように、大きさが大きい方の粉末Ａの主成分は鉄である一方、大きさが小さい方の粉末Ｂの主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、粉末Ｂのホウ素モル濃度は希土類元素のモル濃度の０．０１倍であった。また、粉末Ｂの主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。 Next, 50 g of magnetized scraps subjected to the oxidation treatment were placed in a carbon crucible (made of graphite) having dimensions of an outer diameter of 70 mm, a height of 70 mm, and a thickness of 10 mm, and then 1 at 1800 ° C. in an industrial argon gas atmosphere. Heat treated for hours. Thereafter, the carbon crucible was cooled to room temperature, and a single lump was fixed to the crucible as a heat-treated product in the carbon crucible (FIG. 2-1). If this lump is left in the air for 1 day, it spontaneously disintegrates into a powder with an acetylene odor (Fig. 2-2), and the contents of the carbon crucible are passed through a sieve with an opening of 120 µm. It was possible to collect two types of powders (powder A and powder B) having different sizes (FIGS. 2-3). Table 5 shows the results of ICP analysis and gas analysis of powder A and powder B, respectively. As is clear from Table 5, the main component of powder A having a larger size is iron, while the main component of powder B having a smaller size is a rare earth element, and the rare earth element is separated from iron as a powder. I found out that I was able to. In addition, the boron molar concentration of the powder B was 0.01 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder B was a rare earth element hydroxide.
実施例４：
酸化処理を行った磁石加工屑を２０００℃で熱処理すること以外は実施例３と同様にして実験を行ったところ、実施例３の場合と同様に、炭素るつぼ内には熱処理物として単一の塊状物がるつぼに固着して存在した。この塊状物は、空気中で１日放置しておくと、アセチレン臭を発しながら自然に崩壊して粉末となり、炭素るつぼの内容物を目開きが１２０μｍの篩にかけることで大きさが異なる２種類の粉末（粉末Ａと粉末Ｂ）を回収することができた。粉末ＡのＳＥＭ・ＥＤＸ分析結果と粉末ＢのＩＣＰ分析結果を表６に示す。表６から明らかなように、大きさが大きい方の粉末Ａの主成分は鉄である一方、大きさが小さい方の粉末Ｂの主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、粉末Ｂのホウ素モル濃度は希土類元素のモル濃度の０．０２倍であった。また、粉末Ｂの主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 4:
An experiment was conducted in the same manner as in Example 3 except that the magnetized scraps subjected to the oxidation treatment were heat-treated at 2000 ° C. As in the case of Example 3, a single heat-treated product was placed in the carbon crucible. A lump was fixed to the crucible. When this lump is left in the air for one day, it naturally disintegrates into a powder while producing an acetylene odor, and the size of the lump differs by passing the contents of the carbon crucible through a sieve having an opening of 120 μm 2 Various types of powders (powder A and powder B) could be recovered. Table 6 shows the SEM / EDX analysis results of Powder A and the ICP analysis results of Powder B. As is clear from Table 6, the main component of powder A having a larger size is iron, while the main component of powder B having a smaller size is a rare earth element, and the rare earth element is separated from iron as a powder. I found out that I was able to. In addition, the boron molar concentration of the powder B was 0.02 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder B was a rare earth element hydroxide.
実施例５：
単一の塊状物を空気中で１日間放置するかわりに、室温で水中に１日間浸漬すること以外は実施例３と同様にして実験を行ったところ、この単一の塊状物はアセチレン臭を発する気体を発しながら水中で自然に崩壊して粉末となった。この粉末を吸引濾過して回収し、自然乾燥させてから目開きが１２０μｍの篩にかけることで大きさが異なる２種類の粉末（粉末Ａと粉末Ｂ）を回収することができた。粉末ＡのＳＥＭ・ＥＤＸ分析結果と粉末ＢのＩＣＰ分析結果を表７に示す。表７から明らかなように、大きさが大きい方の粉末Ａの主成分は鉄である一方、大きさが小さい方の粉末Ｂの主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、粉末Ｂのホウ素モル濃度は希土類元素のモル濃度の０．０１倍であった。また、粉末Ｂの主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 5:
An experiment was carried out in the same manner as in Example 3 except that the single lump was immersed in water at room temperature for 1 day instead of being left in the air for 1 day. This single lump showed an acetylene odor. It disintegrated spontaneously in water while emitting gas, and became powder. The powder was recovered by suction filtration, and naturally dried, and then passed through a sieve having an opening of 120 μm, whereby two types of powders (powder A and powder B) having different sizes could be recovered. Table 7 shows the SEM / EDX analysis results of powder A and the ICP analysis results of powder B. As is clear from Table 7, the main component of powder A having a larger size is iron, while the main component of powder B having a smaller size is a rare earth element, and the rare earth element is separated from iron as a powder. I found out that I was able to. In addition, the boron molar concentration of the powder B was 0.01 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder B was a rare earth element hydroxide.
実施例６：
酸化処理を行った磁石加工屑５０ｇと粒径が１２５μｍを超えるカーボンブラック（東海カーボン社製のファーネスブラック）２０ｇの混合物を１４５０℃で熱処理すること以外は実施例１と同様にして実験を行ったところ、炭素るつぼ内には熱処理物として単一の塊状物がるつぼに固着せずに存在した。この塊状物１ｇをプレッシャークッカー試験機（平山製作所社製のＰＣ−２４２ＨＳ、以下同じ）を用いて１２０℃、１００％ＲＨ、２気圧の高温・高湿度・高圧の条件で１時間処理すると、塊状物の一部が崩壊して粉末となった。塊状物と粉末を磁選によって分離し、両者のＩＣＰ分析とガス分析を行った。結果を表８に示す。表８から明らかなように、塊状物の主成分は鉄である一方、粉末の主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、粉末のホウ素モル濃度は希土類元素のモル濃度の０．２０倍であった。また、粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 6:
An experiment was conducted in the same manner as in Example 1 except that a mixture of 50 g of magnetized scraps subjected to oxidation treatment and 20 g of carbon black (furnace black manufactured by Tokai Carbon Co., Ltd.) having a particle size exceeding 125 μm was heat-treated at 1450 ° C. However, a single lump was present in the carbon crucible as a heat-treated product without being fixed to the crucible. When 1 g of this lump is treated for 1 hour under conditions of 120 ° C., 100% RH, 2 atm high temperature, high humidity, and high pressure using a pressure cooker tester (PC-242HS manufactured by Hirayama Seisakusho, the same shall apply hereinafter) Part of the material collapsed into powder. The lump and the powder were separated by magnetic separation, and ICP analysis and gas analysis of both were performed. The results are shown in Table 8. As is apparent from Table 8, it was found that the main component of the lump was iron, while the main component of the powder was a rare earth element, and the rare earth element could be separated from iron as a powder. The boron molar concentration of the powder was 0.20 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder was a rare earth element hydroxide.
実施例７：
酸化処理を行った磁石加工屑２０ｇを１４５０℃で熱処理すること以外は実施例３と同様にして実験を行ったところ、炭素るつぼ内には熱処理物として単一の塊状物がるつぼに固着して存在した。この塊状物１ｇをプレッシャークッカー試験機を用いて１２０℃、１００％ＲＨ、２気圧の高温・高湿度・高圧の条件で６時間処理すると、塊状物の一部が崩壊して粉末となった。塊状物と粉末を磁選によって分離し、粉末のＳＥＭ・ＥＤＸ分析を行った。結果を表９に示す。表９から明らかなように、この粉末の主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。また、粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 7:
An experiment was conducted in the same manner as in Example 3 except that 20 g of magnetized scraps subjected to the oxidation treatment were heat-treated at 1450 ° C. As a result, a single lump as a heat-treated material adhered to the crucible in the carbon crucible. Were present. When 1 g of this lump was treated for 6 hours under the conditions of 120 ° C., 100% RH, 2 atm high temperature, high humidity and high pressure using a pressure cooker tester, a part of the lump was disintegrated into powder. The lump and the powder were separated by magnetic separation, and SEM / EDX analysis of the powder was performed. The results are shown in Table 9. As is clear from Table 9, the main component of this powder was a rare earth element, and it was found that the rare earth element could be separated from iron as a powder. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder was a rare earth element hydroxide.
実施例８：
実施例７で得られた塊状物を１００℃に加熱した１ｍｏｌ／Ｌの水酸化ナトリウム水溶液に６時間浸漬すると、塊状物の一部が崩壊して粉末となった。塊状物と粉末を水洗してから乾燥させた後、両者を磁選によって分離し、粉末のＳＥＭ・ＥＤＸ分析を行った。結果を表１０に示す。表１０から明らかなように、この粉末の主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。また、粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 8:
When the lump obtained in Example 7 was immersed in a 1 mol / L aqueous sodium hydroxide solution heated to 100 ° C. for 6 hours, a part of the lump was disintegrated into a powder. After lump and powder were washed with water and dried, both were separated by magnetic separation, and SEM / EDX analysis of the powder was performed. The results are shown in Table 10. As is apparent from Table 10, the main component of this powder was a rare earth element, and it was found that the rare earth element could be separated from iron as a powder. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder was a rare earth element hydroxide.
実施例９：
実施例７で得られた塊状物を室内に２３０日放置しておくと、塊状物の一部が崩壊して粉末となった。塊状物と粉末を磁選によって分離し、粉末のＳＥＭ・ＥＤＸ分析を行った。結果を表１１に示す。表１１から明らかなように、この粉末の主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。また、粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 9:
When the lump obtained in Example 7 was left in the room for 230 days, a part of the lump was disintegrated into a powder. The lump and the powder were separated by magnetic separation, and SEM / EDX analysis of the powder was performed. The results are shown in Table 11. As is apparent from Table 11, the main component of this powder was a rare earth element, and it was found that the rare earth element could be separated from iron as a powder. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder was a rare earth element hydroxide.
実施例１０：
酸化処理を行った磁石加工屑５０ｇと粒径が１２５μｍを超えるカーボンブラック（東海カーボン社製のシーストＳＯ）２０ｇの混合物を１４５０℃で熱処理すること以外は実施例１と同様にして実験を行ったところ、実施例１の場合と同様に、炭素るつぼ内には熱処理物として２種類の塊状物がるつぼに固着せずに存在した。この２種類の塊状物は、空気中で１日間放置しても変化が認められなかったが、プレッシャークッカー試験機を用いて１２０℃、１００％ＲＨ、２気圧の高温・高湿度・高圧の条件で６時間処理すると、一方の塊状物が崩壊して粉末となった。塊状物と粉末を磁選によって分離し、粉末のＩＣＰ分析を行った。結果を表１２に示す。表１２から明らかなように、粉末の主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、粉末のホウ素モル濃度は希土類元素のモル濃度の０．３５倍であった。また、粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 10:
An experiment was performed in the same manner as in Example 1 except that a mixture of 50 g of magnetized scraps subjected to the oxidation treatment and 20 g of carbon black having a particle size exceeding 125 μm (Seat SO manufactured by Tokai Carbon Co., Ltd.) was heat-treated at 1450 ° C. However, as in the case of Example 1, two kinds of lumps were present in the carbon crucible without being fixed to the crucible as heat-treated products. These two types of lump did not change even after being left in the air for 1 day, but using a pressure cooker tester, the conditions were 120 ° C, 100% RH, 2 atm high temperature, high humidity, and high pressure. For 6 hours, one lump collapsed into a powder. The lump and powder were separated by magnetic separation, and ICP analysis of the powder was performed. The results are shown in Table 12. As is clear from Table 12, the main component of the powder was a rare earth element, and it was found that the rare earth element could be separated from iron as a powder. The boron molar concentration of the powder was 0.35 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder was a rare earth element hydroxide.
実施例１１：
酸化処理を行った磁石加工屑５０ｇと粒径が１２５μｍを超えるカーボンブラック（東海カーボン社製のシーストＳＯ）５０ｇの混合物を１４５０℃で熱処理すること以外は実施例１と同様にして実験を行ったところ、実施例１の場合と同様に、炭素るつぼ内には熱処理物として２種類の塊状物がるつぼに固着せずに存在した。この２種類の塊状物は、空気中で１日間放置しても変化が認められなかったが、プレッシャークッカー試験機を用いて１２０℃、１００％ＲＨ、２気圧の高温・高湿度・高圧の条件で６時間処理すると、一方の塊状物が崩壊して粉末となった。塊状物と粉末を磁選によって分離し、粉末のＩＣＰ分析を行った。結果を表１３に示す。表１３から明らかなように、粉末の主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、粉末のホウ素モル濃度は希土類元素のモル濃度の０．３４倍であった。また、粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 11:
The experiment was performed in the same manner as in Example 1 except that a mixture of 50 g of magnetized scraps subjected to oxidation treatment and 50 g of carbon black (Seat SO manufactured by Tokai Carbon Co., Ltd.) having a particle size exceeding 125 μm was heat-treated at 1450 ° C. However, as in the case of Example 1, two kinds of lumps were present in the carbon crucible without being fixed to the crucible as heat-treated products. These two types of lump did not change even after being left in the air for 1 day, but using a pressure cooker tester, the conditions were 120 ° C, 100% RH, 2 atm high temperature, high humidity, and high pressure. For 6 hours, one lump collapsed into a powder. The lump and powder were separated by magnetic separation, and ICP analysis of the powder was performed. The results are shown in Table 13. As is apparent from Table 13, the main component of the powder was a rare earth element, and it was found that the rare earth element could be separated from iron as a powder. The boron molar concentration of the powder was 0.34 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder was a rare earth element hydroxide.
実施例１２：
酸化処理を行った磁石加工屑５０ｇと粒径が１２５μｍ未満のカーボンブラック（東海カーボン社製のシーストＳＯ）１０ｇの混合物を１４５０℃で熱処理すること以外は実施例１と同様にして実験を行ったところ、炭素るつぼ内には熱処理物として単一の塊状物がるつぼに固着して存在した。この塊状物は、空気中で１日間放置しても変化が認められなかったが、プレッシャークッカー試験機を用いて１２０℃、１００％ＲＨ、２気圧の高温・高湿度・高圧の条件で６時間処理すると、塊状物の一部が崩壊して粉末となった。塊状物と粉末を磁選によって分離し、粉末のＩＣＰ分析を行った。結果を表１４に示す。表１４から明らかなように、粉末の主成分は希土類元素であり、希土類元素を粉末として鉄から分離することができたことがわかった。なお、粉末のホウ素モル濃度は希土類元素のモル濃度の０．３３倍であった。また、粉末の主体が希土類元素の水酸化物であることをＸ線結晶回析により確認した。
Example 12:
An experiment was conducted in the same manner as in Example 1 except that a mixture of 50 g of magnetized scraps subjected to oxidation treatment and 10 g of carbon black having a particle size of less than 125 μm (Seat SO manufactured by Tokai Carbon Co., Ltd.) was heat-treated at 1450 ° C. However, in the carbon crucible, a single lump was fixed to the crucible as a heat-treated product. This lump did not change when left in air for 1 day, but it was 6 hours at 120 ° C, 100% RH, 2 atm high temperature, high humidity, and high pressure using a pressure cooker tester. When processed, a part of the lump collapsed into a powder. The lump and powder were separated by magnetic separation, and ICP analysis of the powder was performed. The results are shown in Table 14. As is clear from Table 14, the main component of the powder was a rare earth element, and it was found that the rare earth element could be separated from iron as a powder. The boron molar concentration of the powder was 0.33 times the molar concentration of the rare earth element. Further, it was confirmed by X-ray crystal diffraction that the main component of the powder was a rare earth element hydroxide.
本発明は、低コストで簡易なリサイクルシステムとして実用化が可能な、少なくとも希土類元素と鉄族元素を含む処理対象物から希土類元素を回収する方法を提供することができる点において産業上の利用可能性を有する。 INDUSTRIAL APPLICABILITY The present invention is industrially applicable in that it can provide a method for recovering a rare earth element from a processing object containing at least a rare earth element and an iron group element, which can be put into practical use as a low-cost and simple recycling system. Have sex.
Claims (7)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2013245620A JP6299181B2 (en) | 2012-11-28 | 2013-11-28 | Recovery method of rare earth elements |
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2012260225 | 2012-11-28 | ||
| JP2012260225 | 2012-11-28 | ||
| JP2013021602 | 2013-02-06 | ||
| JP2013021602 | 2013-02-06 | ||
| JP2013245620A JP6299181B2 (en) | 2012-11-28 | 2013-11-28 | Recovery method of rare earth elements |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2014169497A JP2014169497A (en) | 2014-09-18 |
| JP6299181B2 true JP6299181B2 (en) | 2018-03-28 |
Family
ID=51692069
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2013245620A Active JP6299181B2 (en) | 2012-11-28 | 2013-11-28 | Recovery method of rare earth elements |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6299181B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6323284B2 (en) * | 2014-09-29 | 2018-05-16 | 日立金属株式会社 | Recovery method of rare earth elements |
| KR101662445B1 (en) * | 2015-05-07 | 2016-10-04 | 주식회사 에이.엠.씨 | The selective leaching method of only the rare earth elements in the NdFeB magnet scrap |
| KR101792352B1 (en) | 2015-11-16 | 2017-11-02 | 주식회사 에이.엠.씨 | The Selective Dissolving Method of Rare Earth Elements by Hydrochloric acid in the Scrapped permanent magnet NdFeB |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58136728A (en) * | 1982-02-08 | 1983-08-13 | Sumitomo Special Metals Co Ltd | Regenerating method of permanent magnet material |
| WO1998015667A1 (en) * | 1996-10-08 | 1998-04-16 | General Electric Company | Reduction-melting process to form rare earth-transition metal alloys and the alloys |
| JP2002012921A (en) * | 2000-06-30 | 2002-01-15 | Sumitomo Metal Ind Ltd | Method for regenerating rare earth magnet scrap |
| JP3716908B2 (en) * | 2000-08-22 | 2005-11-16 | 信越化学工業株式会社 | Recovery method of rare earth elements from sludge containing rare earth elements |
| WO2007119846A1 (en) * | 2006-04-17 | 2007-10-25 | Santoku Corporation | Method of recovering useful materials from scrap of rare earth-iron-boron magnet |
| JP5273241B2 (en) * | 2009-02-27 | 2013-08-28 | 国立大学法人大阪大学 | Method for recovering rare earth elements from RE-TM mixture |
| JP2012041588A (en) * | 2010-08-17 | 2012-03-01 | Akita Univ | Separation method and separation system for rare earth element by chloride volatilization method |
| WO2013018710A1 (en) * | 2011-07-29 | 2013-02-07 | 日立金属株式会社 | Method for recovering rare earth element |
| JP5767993B2 (en) * | 2012-03-26 | 2015-08-26 | Jx日鉱日石金属株式会社 | Method for enriching rare earth elements from rare earth-containing materials |
| JP5905782B2 (en) * | 2012-03-26 | 2016-04-20 | Ｊｘ金属株式会社 | Method for enriching rare earth elements from rare earth-containing materials |
| JP6060704B2 (en) * | 2013-01-28 | 2017-01-18 | 日立金属株式会社 | Recovery method of rare earth elements |
-
2013
- 2013-11-28 JP JP2013245620A patent/JP6299181B2/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| JP2014169497A (en) | 2014-09-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5327409B2 (en) | Recovery method of rare earth elements | |
| JP5598635B1 (en) | Recovery method of rare earth elements | |
| JP6233321B2 (en) | Recovery method for heavy rare earth elements | |
| JP6060704B2 (en) | Recovery method of rare earth elements | |
| JP6299181B2 (en) | Recovery method of rare earth elements | |
| JP5853815B2 (en) | Recovery method of rare earth elements | |
| JP6786910B2 (en) | A method of separating both from a treatment object containing light rare earth elements and heavy rare earth elements | |
| JP6413877B2 (en) | Recovery method of rare earth elements | |
| JP6281261B2 (en) | Method for reducing boron content of rare earth oxides containing boron | |
| WO2015147181A1 (en) | Method for recovering rare earth element | |
| JP6347225B2 (en) | Recovery method of rare earth elements | |
| JPWO2017034009A1 (en) | Useful method for separating light rare earth elements from heavy rare earth elements | |
| JP6988293B2 (en) | Method for producing carbonates of rare earth elements | |
| JP6988292B2 (en) | Method for producing carbonates of rare earth elements | |
| JP6264195B2 (en) | Recovery method of rare earth elements | |
| JP7067196B2 (en) | Method for producing rare earth element oxalate | |
| JP2017043807A (en) | Method for recovering rare earth element | |
| JP6323284B2 (en) | Recovery method of rare earth elements | |
| JP2018141181A (en) | Method for preparing rare earth element solution | |
| JP2016183376A (en) | Rare earth element collection method | |
| JP2019165118A (en) | Method for manufacturing solvent extraction hydrochloric acid solution using rare earth oxalate | |
| JP2018003090A (en) | Method for separating aluminum from composite oxide of rear earth elements and aluminum | |
| JP2016183064A (en) | Method for reducing boron content in boron-containing oxide of rare-earth element |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20161022 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20170809 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20170815 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20170830 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20180130 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20180212 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6299181 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |