JPH07145427A - Method for recovering and recycling palladium or palladium alloy from contact material - Google Patents
Method for recovering and recycling palladium or palladium alloy from contact materialInfo
- Publication number
- JPH07145427A JPH07145427A JP31727893A JP31727893A JPH07145427A JP H07145427 A JPH07145427 A JP H07145427A JP 31727893 A JP31727893 A JP 31727893A JP 31727893 A JP31727893 A JP 31727893A JP H07145427 A JPH07145427 A JP H07145427A
- Authority
- JP
- Japan
- Prior art keywords
- palladium
- acid
- base material
- alloy
- contact material
- 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.)
- Pending
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
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は黄銅、洋白等の銅系合金
母材にパラジウム又はパラジウム合金を張り合わせた電
気接点のスクラップから効率良くパラジウムを回収・再
利用する方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for efficiently recovering and reusing palladium from scraps of electrical contacts made by bonding palladium or palladium alloy to a copper-based alloy base material such as brass and nickel silver.
【０００２】[0002]
【従来の技術】黄銅、洋白等の銅系合金の母材にＰｄ、
Ａｇ−Ｐｄ合金又はＡｕ−Ａｇ−Ｐｄ合金等のパラジウ
ム系合金を張り合わせて製造された電気接点は、リレー
や電話交換器等に広く用いられている。その製造過程で
出るプレスくずや不良品、さらに使用済のリレーや電話
交換器などのスクラップからパラジウムを回収する方法
として、接点材料をそのまま全量溶解してしまう方法や
母材とパラジウムを分離する方法などが用いられてい
る。具体的には前者は接点材料をそのまま硝酸、王水等
で溶解し、その液から湿式精製によりパラジウムを回収
するものであり、後者は接点材を直接硫酸銅溶液中で陽
極として電解し、パラジウムをスライムとして母材と分
離させる方法（特開平３−１０４８９４）や、接点材を
硫酸−過酸化水素混合液や熱濃硫酸等で母材のみを選択
的に溶解し、パラジウムを分離させる方法等が用いられ
ていた。ところが上に述べた方法には次のような問題点
があった。前者の場合接点材をすべて溶解する為薬品代
等のコストが高くなり、また溶解に要する時間や精製期
間も長くなり金利の面でも経済的に不利であった。また
後者の場合母材の溶解が不完全であったり、接合部に拡
散層を生じ、母材の成分が入り込んでくるため分離した
パラジウムの品位が低く、このままでは再利用すること
が困難であった。これをさらに精製しようとする場合、
パラドスアンミン法等により精製するのが一般的である
が、薬品代がさらにかかり、精製に時間がかかってしま
うという問題があった。2. Description of the Related Art Pd is used as a base material for copper alloys such as brass and nickel silver.
Electrical contacts manufactured by laminating a palladium-based alloy such as an Ag-Pd alloy or an Au-Ag-Pd alloy are widely used in relays, telephone exchanges and the like. As a method of recovering palladium from press scraps and defective products produced in the manufacturing process, and scraps such as used relays and telephone exchanges, a method of completely dissolving the contact material as it is or a method of separating palladium from the base material Are used. Specifically, the former is one in which the contact material is directly dissolved in nitric acid, aqua regia, etc., and palladium is recovered from the solution by wet refining, while the latter is directly electrolyzed as a positive electrode in a copper sulfate solution to form palladium. As a slime to separate from the base material (Japanese Patent Laid-Open No. 3-104894), a method of selectively dissolving only the base material with a sulfuric acid-hydrogen peroxide mixture solution, hot concentrated sulfuric acid or the like, and separating palladium from the contact material, etc. Was used. However, the method described above has the following problems. In the former case, all contact materials are dissolved, so the cost of chemicals is high, and the time required for dissolution and the refining period are long, which is economically disadvantageous in terms of interest rates. In the latter case, the dissolution of the base metal is incomplete, or a diffusion layer is formed at the joint, and the components of the base metal enter, so the quality of the separated palladium is low and it is difficult to reuse it as it is. It was If you want to refine this further,
Although it is general to purify by the parados ammine method or the like, there is a problem in that the cost of chemicals is further increased and the purification takes time.
【０００３】[0003]
【発明が解決しようとする課題】本発明は上記問題点を
解決し、薬品代等のコストがあまりかからず、短時間で
品位の良いパラジウムを回収する方法、特に後工程でさ
らに精製することなくそのまま再利用できるような高品
位のパラジウムを得る回収方法を提供する。DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems and is a method for recovering good quality palladium in a short time with less cost for chemicals and the like, and further purification in a subsequent step. Provided is a recovery method for obtaining high-quality palladium that can be reused as it is.
【０００４】[0004]
【課題を解決するための手段】本発明は、銅又は銅合金
の母材にパラジウム又はパラジウム合金を接合した接点
材料からのパラジウム又はパラジウム合金の回収におい
て、クロスバー接点材料を陽極としての電解及び／又は
熱濃硫酸若しくは硫酸−過酸化水素混合溶液による溶解
にて母材を溶解分離させた後、得られたパラジウムを酸
処理して不純物の多い表面部を溶解除去することにより
達成できる。なお、ここで行う酸処理は、塩酸−過酸化
水素混合液、硝酸、王水又は硝酸−過酸化水素混合液を
用いると良い。DISCLOSURE OF THE INVENTION The present invention relates to electrolysis using a crossbar contact material as an anode in the recovery of palladium or a palladium alloy from a contact material in which palladium or a palladium alloy is joined to a base material of copper or a copper alloy. Alternatively, it can be achieved by dissolving and separating the base material by dissolving with hot concentrated sulfuric acid or a mixed solution of sulfuric acid-hydrogen peroxide, and then subjecting the obtained palladium to acid treatment to dissolve and remove the surface portion containing many impurities. In addition, for the acid treatment performed here, it is preferable to use a hydrochloric acid-hydrogen peroxide mixed solution, nitric acid, aqua regia, or a nitric acid-hydrogen peroxide mixed solution.
【０００５】[0005]
【作用】本発明ではその第一工程としてパラジウムと母
材の分離を電解法や薬液による溶解法を用いている。電
解法としては例えば硫酸銅溶液のような電解液中へ、ア
ノードバッグを施したチタンバスケットへ接点材料を充
填したものと銅板を浸漬し、銅板を陰極、接点材料を陽
極として電解することにより、接点材料の母材の銅は、
電解質中へ溶解した後、さらに陰極上へ析出し、またパ
ラジウムはアノードスライムとしてアノードバッグ中に
堆積するため、これを取り出すことによりパラジウムが
分離できる。なおこのとき、電解とともに電解液中には
銅だけではなく母材中の亜鉛、ニッケル等、他の成分も
溶解してゆくが、銅以外の成分は陰極に析出しにくいた
め、電解液中の銅濃度は低下し、亜鉛等の濃度は上昇す
る。ところがあまり亜鉛等の濃度が上昇すると電解液中
に溶けきれなくなって硫酸亜鉛、硫酸ニッケル等の析出
が起き、これが材料の表面を覆って電流を流れにくくし
てしまうという問題がある。また銅濃度が低下しすぎる
と陰極から水素の発生が起こって、大気と混合し、爆発
性の混合気を形成する危険がある。そのため、電解液は
ある程度銅濃度が低下した時点で更新又は銅を追加する
方法が採用される。また薬液による溶解法としては、熱
濃硫酸又は硫酸−過酸化水素混合液が用いられる。これ
らの薬液は銅などの母材は溶解するが、パラジウムを溶
解することがないため、安心して用いることができる。
パラジウムと母材の分離方法として、電解法と薬液によ
る溶解法のどちらか一方を用いるだけでもよいが、電解
法の場合母材の溶解速度は速いが、母材がなくなった後
も電解をつづけるとパラジウムが溶解してしまう問題が
あり、一方薬液による溶解法では、パラジウムを溶解す
る恐れはないが、母材の溶解速度が遅いことより、両者
の併用、つまりある程度まで電解法により母材を溶解
し、最後に薬液で溶解する方法が効率的で望ましい。こ
うして得られたパラジウムは、Ｃｕなどの不純物を含ん
でおり、そのままパラジウムもしくはパラジウム合金と
して使用するには品位が不十分である。その後塩酸−過
酸化水素混合液、硝酸、王水または硝酸−過酸化水素混
合液のいずれかで酸処理が行われる。これは上記パラジ
ウムと母材の分離処理で一応パラジウムは分離できた
が、パラジウム表面には母材の拡散層が残っており、こ
の層は熱濃硫酸又は硫酸−過酸化水素混合液では除去で
きないため、再度別の酸による処理が必要となる。なお
この酸処理による溶解量は得られたパラジウム重量の１
乃至５％が適当である。１％未満では不純物の多い部分
を溶かしきれずに回収されたパラジウムは品位の低いも
のとなり、また５％以上溶かしても品位の向上はせず、
溶解するパラジウム量が増えるだけのため、歩留りが低
下してしまうためである。得られたパラジウム又はパラ
ジウム合金は、そのまま再度溶解加工等により純パラジ
ウムやパラジウム合金などの接点材料として再利用出来
る為、従来の様にパラジウムの精製工程を経る必要が無
い。In the present invention, as the first step, the separation of the palladium and the base material is performed by the electrolytic method or the dissolution method using the chemical solution. As an electrolytic method, for example, in an electrolytic solution such as a copper sulfate solution, a contact material filled in a titanium basket provided with an anode bag and a copper plate are immersed, and by electrolyzing the copper plate as a cathode and the contact material as an anode, The base material copper of the contact material is
After being dissolved in the electrolyte, it is further deposited on the cathode, and palladium is deposited as anode slime in the anode bag, so that the palladium can be separated by taking it out. At this time, not only copper but also other components such as zinc and nickel in the base material are dissolved in the electrolytic solution along with electrolysis, but components other than copper are less likely to deposit on the cathode, so Copper concentration decreases and zinc concentration increases. However, if the concentration of zinc or the like increases too much, it will not be completely dissolved in the electrolytic solution, and zinc sulfate, nickel sulfate or the like will be deposited, which will cover the surface of the material and make it difficult for current to flow. On the other hand, if the copper concentration is too low, hydrogen will be generated from the cathode and may mix with the atmosphere to form an explosive mixture. Therefore, a method is adopted in which the electrolytic solution is updated or copper is added when the copper concentration is reduced to some extent. As a dissolution method using a chemical solution, hot concentrated sulfuric acid or a sulfuric acid-hydrogen peroxide mixture solution is used. Although these chemicals dissolve the base material such as copper, but do not dissolve palladium, they can be safely used.
As a method for separating palladium from the base material, either one of the electrolytic method and the dissolution method using a chemical solution may be used.In the electrolytic method, the dissolution rate of the base material is fast, but electrolysis is continued even after the base material disappears. However, there is no risk of palladium being dissolved by the chemical solution method, but the dissolution rate of the base metal is slow. A method of dissolving and finally dissolving with a drug solution is efficient and desirable. The palladium thus obtained contains impurities such as Cu and is of insufficient quality to be used as it is as palladium or palladium alloy. After that, acid treatment is performed with any one of a hydrochloric acid-hydrogen peroxide mixed solution, nitric acid, aqua regia, or a nitric acid-hydrogen peroxide mixed solution. Palladium could be separated for the time being by the above-mentioned separation treatment of palladium and base material, but a diffusion layer of the base material remained on the palladium surface, and this layer cannot be removed by hot concentrated sulfuric acid or sulfuric acid-hydrogen peroxide mixture solution. Therefore, another acid treatment is required again. The amount of dissolution by this acid treatment was 1 of the weight of palladium obtained.
-5% is suitable. If it is less than 1%, the palladium recovered without being able to completely dissolve the portion having a large amount of impurities becomes of low quality, and even if it is dissolved by 5% or more, the quality is not improved.
This is because the amount of dissolved palladium only increases and the yield decreases. The obtained palladium or palladium alloy can be reused as it is as a contact material such as pure palladium or palladium alloy by melting processing or the like, so that it is not necessary to go through the purification step of palladium as in the conventional case.
【０００６】[0006]
【実施例】以下に本発明の実施例を示す。パラジウムを
約11％含むクロスバー接点材料の廃材 150kgをチタン製
バスケット（ 330× 400×40mm）10個に分けて入れ５槽
の電解槽へ２個ずつ陽極として設置し、陰極には銅板
（ 500× 650mm）を各槽３枚ずつ用いて電解を開始し
た。なお電解液としては銅濃度50ｇ／ｌの硫酸銅及び硫
酸 150ｇ／ｌの水溶液を用いた。電解電流は各槽ごとに
電流 250Ａ（電流密度３Ａ／cm2 ）にて電解し、85時間
電解を行った時点で溶け残り材を取り出したところ、25
kgの溶け残り材が得られた。この溶け残り材を回転式ド
ラムに入れ、さらに20重量％の硫酸60ｌと35重量％の過
酸化水素水５kgを加えて24時間回転、撹拌させ、母材を
完全に溶解した。このときパラジウム16.2kgが得られ
た。上記で得られたパラジウムを回転式ドラムに入れ、
さらに35重量％の塩酸20ｌ及び35重量％の過酸化水素水
５kgを加えて３時間回転、撹拌させながら処理して表面
を溶解させた。処理後、濾過、水洗、乾燥を行ったとこ
ろパラジウム15.9Kgが得られた。この得られたパラジウ
ム材を分析したところ表１のような成分であり、鋳造し
てインゴットとすることにより、そのまま再利用が可能
であった。なお、この回収処理に要した時間は、電解に
４日間、硫酸−過酸化水素水処理に１日間、塩酸−過酸
化水素水処理に１日間で計６日間であった。EXAMPLES Examples of the present invention will be shown below. 150 kg of crossbar contact material waste material containing about 11% of palladium was divided into 10 titanium baskets (330 x 400 x 40 mm) and placed in two electrolytic cells as two anodes, and a copper plate (500 X 650 mm) was used to start electrolysis using 3 sheets in each tank. As the electrolytic solution, an aqueous solution of copper sulfate having a copper concentration of 50 g / l and sulfuric acid of 150 g / l was used. The electrolysis current was electrolyzed at a current of 250 A (current density 3 A / cm 2 ) in each tank, and the unmelted material was taken out after 85 hours of electrolysis.
The unmelted material of kg was obtained. The undissolved material was placed in a rotary drum, 60 l of 20% by weight sulfuric acid and 5 kg of 35% by weight hydrogen peroxide solution were further added, and the mixture was rotated and stirred for 24 hours to completely dissolve the base material. At this time, 16.2 kg of palladium was obtained. Put the palladium obtained above in a rotary drum,
Further, 20 liters of 35 wt% hydrochloric acid and 5 kg of 35 wt% hydrogen peroxide solution were added and treated for 3 hours while rotating and stirring to dissolve the surface. After the treatment, filtration, washing with water and drying gave 15.9 kg of palladium. When the obtained palladium material was analyzed, it had the components shown in Table 1, and it was possible to reuse it as it was by casting it into an ingot. The time required for this recovery treatment was 4 days for electrolysis, 1 day for sulfuric acid-hydrogen peroxide solution treatment, and 1 day for hydrochloric acid-hydrogen peroxide solution treatment, for a total of 6 days.
【０００７】[0007]
【従来例１】実施例と同様に処理を進めたが、最後の塩
酸−過酸化水素水による表面溶解を行わずに鋳造してイ
ンゴットを作成した。このインゴットの分析値を表１に
示すが、得られたパラジウムインゴットは不純物が多す
ぎ、このままでは再利用できない物であった。PRIOR ART EXAMPLE 1 Processing was carried out in the same manner as in Example, but the ingot was prepared by casting without final surface dissolution with hydrochloric acid-hydrogen peroxide solution. The analytical values of this ingot are shown in Table 1. The obtained palladium ingot had too many impurities and could not be reused as it was.
【０００８】[0008]
【従来例２】従来例１で得られたパラジウム材を鋳造す
る前に湿式精製を行い不純物を除去した。まず従来例１
と同様にして得られたパラジウム材15.5kgを90℃の王水
100ｌ中へ投入し、24時間かけて溶解した。その後、こ
のパラジウムが溶解した王水を水酸化ナトリウム溶液で
中和した後、アルカリ性水素化ホウ素ナトリウム溶液
（20％）30ｌを投入することにより、スポンジ状パラジ
ウム 15.0gが得られた。この得られたスポンジ状パラジ
ウムの分析値を表１に示す。品位的には問題のないパラ
ジウムが得られているが、精製処理に５日間要してお
り、総日数で10日間と、実施例の２倍近くの期間がかか
ってしまった。Conventional Example 2 Prior to casting the palladium material obtained in Conventional Example 1, wet purification was performed to remove impurities. First conventional example 1
15.5 kg of palladium material obtained in the same manner as in 90 ° C aqua regia
It was poured into 100 l and dissolved over 24 hours. Thereafter, the aqua regia in which the palladium was dissolved was neutralized with a sodium hydroxide solution, and then 30 l of an alkaline sodium borohydride solution (20%) was added to obtain 15.0 g of sponge-like palladium. The analytical values of the obtained sponge-like palladium are shown in Table 1. Palladium was obtained without any problem in terms of quality, but the purification treatment required 5 days, and the total number of days was 10 days, which was almost twice as long as that in the example.
【０００９】[0009]
【表１】 [Table 1]
【００１０】[0010]
【発明の効果】本発明のクロスバー接点材料からのパラ
ジウムの回収再利用方法は、接点材料をそのまま陽極と
して電解及び／又は薬品による溶解によりパラジウムと
母材を分離し、得られたパラジウム材表面の不純物の拡
散層を酸処理により溶解除去してそのままで再利用でき
る品位の高いパラジウム材を得るものであり、回収期間
の低減、回収コストの低減に効果のある物である。The method for recovering and reusing palladium from the crossbar contact material according to the present invention is a method in which the contact material is used as an anode as it is, and the palladium and the base material are separated by electrolysis and / or dissolution by chemicals, and the obtained palladium material surface This is to obtain a high-quality palladium material that can be reused as it is by dissolving and removing the diffusion layer of the impurities by acid treatment, and is effective in reducing the recovery period and the recovery cost.
Claims (2)
ラジウム合金を接合した接点材料からの貴金属回収にお
いて、接点材料を陽極としての電解及び／又は熱濃硫酸
若しくは硫酸−過酸化水素混合溶液による溶解にて母材
を溶解分離させた後、得られたパラジウム又はパラジウ
ム合金を酸処理して不純物の多い表面部を溶解除去する
ことを特徴とする、接点材料からのパラジウム又はパラ
ジウム合金の回収・再利用方法。1. Recovery of a noble metal from a contact material in which palladium or a palladium alloy is joined to a base material of copper or a copper alloy, by electrolysis using the contact material as an anode and / or hot concentrated sulfuric acid or a sulfuric acid-hydrogen peroxide mixed solution. After the base material is dissolved and separated by dissolution, the obtained palladium or palladium alloy is treated with an acid to dissolve and remove the surface portion containing many impurities. Recovery of palladium or palladium alloy from the contact material How to reuse.
処理を塩酸−過酸化水素混合液、硝酸、王水又は硝酸−
過酸化水素混合液のいずれかで行うことを特徴とする接
点材料からのパラジウム又はパラジウム合金の回収・再
利用方法。2. The acid treatment of the palladium or palladium alloy is carried out by a hydrochloric acid-hydrogen peroxide mixture, nitric acid, aqua regia or nitric acid.
A method for recovering and reusing palladium or a palladium alloy from a contact material, which is characterized in that it is carried out with one of hydrogen peroxide mixed solutions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31727893A JPH07145427A (en) | 1993-11-24 | 1993-11-24 | Method for recovering and recycling palladium or palladium alloy from contact material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31727893A JPH07145427A (en) | 1993-11-24 | 1993-11-24 | Method for recovering and recycling palladium or palladium alloy from contact material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07145427A true JPH07145427A (en) | 1995-06-06 |
Family
ID=18086453
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP31727893A Pending JPH07145427A (en) | 1993-11-24 | 1993-11-24 | Method for recovering and recycling palladium or palladium alloy from contact material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07145427A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US20120058029A1 (en) * | 2009-03-13 | 2012-03-08 | Neo Performance Materials Limited | Rhenium recovery |
| KR101445252B1 (en) * | 2013-05-07 | 2014-09-29 | (주)비욘드 | pre-treatment method for acquiring gold for cleaning of copper basic material |
| CN104975178A (en) * | 2014-04-04 | 2015-10-14 | 中国科学院生态环境研究中心 | Technology for non-acidification recycling of palladium in waste circuit board |
| CN114686692A (en) * | 2022-03-04 | 2022-07-01 | 金川集团股份有限公司 | Method for extracting metal platinum and palladium from high copper-containing silver electrolysis waste liquid |
-
1993
- 1993-11-24 JP JP31727893A patent/JPH07145427A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120058029A1 (en) * | 2009-03-13 | 2012-03-08 | Neo Performance Materials Limited | Rhenium recovery |
| US8956582B2 (en) * | 2009-03-13 | 2015-02-17 | Maritime House Metals Inc. | Rhenium recovery |
| KR101445252B1 (en) * | 2013-05-07 | 2014-09-29 | (주)비욘드 | pre-treatment method for acquiring gold for cleaning of copper basic material |
| CN104975178A (en) * | 2014-04-04 | 2015-10-14 | 中国科学院生态环境研究中心 | Technology for non-acidification recycling of palladium in waste circuit board |
| CN104975178B (en) * | 2014-04-04 | 2017-06-27 | 中国科学院生态环境研究中心 | The technique that non-acidizing reclaims palladium in discarded circuit board |
| CN114686692A (en) * | 2022-03-04 | 2022-07-01 | 金川集团股份有限公司 | Method for extracting metal platinum and palladium from high copper-containing silver electrolysis waste liquid |
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