JP2000157983A - Method recovering palladium - Google Patents

Method recovering palladium

Info

Publication number
JP2000157983A
JP2000157983A JP33328198A JP33328198A JP2000157983A JP 2000157983 A JP2000157983 A JP 2000157983A JP 33328198 A JP33328198 A JP 33328198A JP 33328198 A JP33328198 A JP 33328198A JP 2000157983 A JP2000157983 A JP 2000157983A
Authority
JP
Japan
Prior art keywords
palladium
oxidation
soln
contg
aqueous solution
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
Application number
JP33328198A
Other languages
Japanese (ja)
Inventor
Masao Narita
政雄 成田
Hisashi Harada
久 原田
Hidemitsu Miyaji
英充 宮地
Toshiyuki Kimura
敏行 木村
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kawasaki Kasei Chemicals Ltd
Original Assignee
Kawasaki Kasei Chemicals Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kawasaki Kasei Chemicals Ltd filed Critical Kawasaki Kasei Chemicals Ltd
Priority to JP33328198A priority Critical patent/JP2000157983A/en
Publication of JP2000157983A publication Critical patent/JP2000157983A/en
Pending legal-status Critical Current

Links

Classifications

    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Recycling

Abstract

PROBLEM TO BE SOLVED: To efficiently recover palladium from an aq. palladium-contg. soln., in which a large amt. of a palladium ion reducing substance coexists by oxidizing the aq. palladium-contg. soln. at a specified pH or lower to break a protective colloid and then letting the palladium-contg. water stand. SOLUTION: An aq. soln. to be treated is an aq. palladium-contg. soln. in which a palladium ion reducing substance coexists. A mixed catalytic soln. of palladium chloride and stannous chloride used in a stage before electroless plating, its waste soln, etc., are exemplified. The oxidation means that the protective palladium ion of the colloidal particle protected by tin ion in an aq. palladium-contg. soln. and having nearly zero valency is broken and converted into a palladium metal particle. Further, the end point of oxidation is judged by a change in the oxidation-reduction potential of the aq. palladium- contg. soln., and the oxidation is stopped when the potential begins to rise.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、パラジウム含有水
溶液からのパラジウムの回収方法に関する。さらに詳し
くは、無電解メッキの下地処理に使われるパラジウムと
すずとの混合触媒液のような、パラジウムイオンに対し
て還元作用を有する物質が共存しているパラジウム含有
水溶液から、資源的に貴重なパラジウム金属を工業的有
利に回収する方法に関する。
[0001] The present invention relates to a method for recovering palladium from an aqueous solution containing palladium. More specifically, from a palladium-containing aqueous solution in which a substance having a reducing action on palladium ions coexists, such as a mixed catalyst solution of palladium and tin used for base treatment of electroless plating, it is a valuable resource The present invention relates to a method for industrially recovering palladium metal.

【0002】[0002]

【従来の技術】ニッケルなどの無電解メッキ技術は、従
来の電解メッキに比べ、接点部分のロスが少ない、緻密
なメッキ被膜が得られる、非導電性の下地でもメッキが
できるなどの多くの利点があり、プラスチック材料、装
飾品、電子機器部品等をメッキする際に多用されてい
る。無電解メッキ技術で物品をメッキする際には、メッ
キ対象物品の下地表面に触媒作用を付加するため、パラ
ジウムとすずの混合触媒液を用いて、下地表面にパラジ
ウム核を付与する手法が行われており、この触媒作用の
付加工程から、この触媒液のみならず、希薄なパラジウ
ムを含有する洗浄水などの水性廃液が多量発生する。
2. Description of the Related Art Electroless plating technology of nickel or the like has many advantages compared to conventional electrolytic plating, such as less loss of a contact portion, a dense plating film, and plating on a non-conductive base. It is widely used when plating plastic materials, decorative articles, electronic device parts and the like. When plating an article by electroless plating technology, a method of adding a palladium nucleus to the base surface using a mixed catalyst solution of palladium and tin is performed to add a catalytic action to the base surface of the article to be plated. In addition, a large amount of aqueous wastewater such as washing water containing dilute palladium is generated from this catalyst addition step in addition to the catalyst liquid.

【0003】このパラジウムを含有する水性廃液には、
通常、塩酸酸性下で塩化第一すずなどの強い還元作用を
有する物質が多量に共存しているので、パラジウムは原
子価が0に近いコロイド粒子として存在している。この
ようなパラジウムを含有する水性廃液からパラジウムを
回収する方法としては、(1)沈殿させて回収する方
法、(2)活性炭などの多孔質担体に吸着させて回収す
る方法、(3)有機溶媒に溶解たキレート試薬で水溶液
から抽出する方法、(4)イオン交換樹脂によって回収
する方法、などが従来から知られている。
[0003] The aqueous waste liquid containing palladium includes:
Normally, palladium is present as colloidal particles having a valence close to 0 because a large amount of a substance having a strong reducing action such as stannous chloride coexists under hydrochloric acid acidity. As a method of recovering palladium from such an aqueous waste liquid containing palladium, (1) a method of recovering by precipitation, (2) a method of recovering by adsorbing on a porous carrier such as activated carbon, and (3) an organic solvent A method of extracting from an aqueous solution with a chelating reagent dissolved in water, (4) a method of recovering with an ion exchange resin, and the like are conventionally known.

【0004】しかし、これら従来の回収方法には、それ
ぞれ以下のような欠点があり、工業的には実施されてい
ない。上記(1)の方法は、パラジウムとともに多量に
共存するすずが同伴され、すずを後工程で分離する必要
があり、工程が繁雑である。上記(2)の方法は、多量
に共存するすずおよび塩酸の影響で、パラジウムの選択
吸着性が良くない。上記(3)の方法は、多量に共存す
るすずがパラジウムコロイド粒子の保護基として作用す
るので、抽出効率が極めて低い。上記(4)の方法は、
パラジウムの選択回収率が低く、操作が繁雑である。
However, these conventional recovery methods have the following disadvantages, respectively, and have not been industrially implemented. In the above method (1), tin coexisting in a large amount with palladium is entrained, and it is necessary to separate tin in a post-process, and the process is complicated. In the method (2), the selective adsorption of palladium is not good due to the influence of tin and hydrochloric acid which coexist in large amounts. In the above method (3), the extraction efficiency is extremely low because a large amount of coexisting tin acts as a protecting group for the palladium colloid particles. The method of (4) above is
Selective recovery of palladium is low and operation is complicated.

【0005】[0005]

【発明が解決しようする課題】本発明は、このようなパ
ラジウム含有排水からパラジウムを回収するにあたり、
複雑な操作を要することなく、酸化処理することで容易
にパラジウムを回収する方法を提供することにある。
DISCLOSURE OF THE INVENTION The present invention relates to the recovery of palladium from such palladium-containing wastewater.
An object of the present invention is to provide a method for easily recovering palladium by performing an oxidation treatment without requiring a complicated operation.

【0006】塩化第一すずのようなパラジウムイオンに
対して還元作用を有する物質が多量に共存するパラジウ
ム含有水溶液中では、パラジウムは0価に近い状態で存
在してはいるが、金属として析出することなく、周囲を
すずイオンに守られた安定なコロイド状態に保たれ、水
に溶解している。そこで、酸化処理によりこの保護コロ
イドの状態を破壊することによりパラジウムのみを金属
として回収できるが、通常の状態で酸化処理を行なう
と、4価のすずイオンが水酸化物となって沈殿し、この
際パラジウムも同伴されて沈殿するので、パラジウムを
選択的に回収することができない。また、過度に酸化す
るとパラジウムを2価のパラジウムイオンに酸化してし
まい、金属として回収することができない。
In a palladium-containing aqueous solution in which a large amount of a substance having a reducing action on palladium ions such as stannous chloride coexists, palladium is present in a state close to zero valence, but is deposited as a metal. No, it is kept in a stable colloidal state protected by tin ions and dissolved in water. Thus, only palladium can be recovered as a metal by destroying the state of the protective colloid by an oxidation treatment. However, when oxidation treatment is performed in a normal state, tetravalent tin ions precipitate as hydroxides. In this case, palladium is also entrained and precipitates, so that palladium cannot be selectively recovered. In addition, excessive oxidation oxidizes palladium to divalent palladium ions and cannot be recovered as a metal.

【0007】本発明者らは、塩化第一すずのようなパラ
ジウムイオンに対して還元作用を有する物質が多量共存
するパラジウム含有水溶液を、単純な酸化処理でパラジ
ウムのみを効率よく回収する方法について鋭意検討した
結果、まず、水溶液をpH1以下の酸性状態として酸化
処理を施し保護コロイドを破壊し、該パラジウム含有水
を放置することにより、原子価が0に近いコロイド粒子
状のパラジウムのみをパラジウム金属として沈殿回収で
きることを見い出した。しかしながら、この酸化処理が
不十分な場合、コロイド粒子状の状態で残ったパラジウ
ムイオンは、金属として回収できず、過度に酸化すると
すずの沈殿や、パラジウムが2価に酸化され、金属とし
て回収できなくなる。そのため、この酸化処理の終点を
効率よくかつ、確実に判定する方法について検討した結
果、パラジウム含有水の酸化還元電位の変化で効率よく
判定する方法を見いだし、本発明を完成した。
The present inventors have intensively studied a method for efficiently recovering only palladium from a palladium-containing aqueous solution in which a large amount of a substance having a reducing action on palladium ions such as stannous chloride coexists by a simple oxidation treatment. As a result, first, the aqueous solution was oxidized to an acidic state of pH 1 or less to destroy the protective colloid, and the palladium-containing water was allowed to stand, whereby only palladium in the form of colloidal particles having a valence close to 0 was precipitated as palladium metal. We found that we could collect it. However, if this oxidation treatment is insufficient, the palladium ions remaining in the form of colloidal particles cannot be recovered as metal. If excessively oxidized, precipitation of tin or palladium is oxidized to divalent and cannot be recovered as metal. . Therefore, as a result of studying a method for efficiently and reliably determining the end point of the oxidation treatment, a method for efficiently determining the end point of the palladium-containing water based on the change in the oxidation-reduction potential was found, and the present invention was completed.

【0008】本発明の目的は、次のとおりである。1.
塩化第一すずのようなパラジウムイオンに対して還元作
用を有する物質が多量共存するパラジウム含有水溶液か
ら、パラジウムを効率的に回収することができる工業的
に有利な方法を提供すること。
The objects of the present invention are as follows. 1.
An industrially advantageous method capable of efficiently recovering palladium from a palladium-containing aqueous solution in which a large amount of a substance having a reducing action on palladium ions such as stannous chloride coexists.

【0009】[0009]

【課題を解決するための手段】上記課題を解決するため
に、本発明では、パラジウムイオンに対して還元作用を
有する物質が共存しているパラジウム含有水溶液から、
パラジウムを金属として回収するにあたり、まず、該パ
ラジウム含有水溶液について、pH1以下で酸化処理を
行ない、保護コロイドを破壊した後、該パラジウム含有
水を放置することを特徴とする、パラジウムの回収方法
を提供するものであり、その酸化処理の終点を酸化還元
電位の変化を利用して判定する方法を提供する。
According to the present invention, there is provided a palladium-containing aqueous solution containing a substance having a reducing action on palladium ions.
In recovering palladium as a metal, a method for recovering palladium is provided, in which, first, the aqueous solution containing palladium is oxidized at a pH of 1 or less to destroy protective colloid, and the water containing palladium is allowed to stand. The present invention provides a method for determining the end point of the oxidation treatment by using a change in the oxidation-reduction potential.

【0010】[0010]

【発明の実施の形態】以下、本発明を詳細に説明する。
本発明において処理の対象とされる水溶液は、パラジウ
ムイオンに対して還元作用を有する物質が共存している
パラジウム含有水溶液である。具体的には、無電解メッ
キの前工程に用いられる塩化パラジウムと塩化第一すず
との混合触媒液、その廃液や、無電解メッキの前工程で
発生した洗浄排水等が挙げられる。
BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The aqueous solution to be treated in the present invention is a palladium-containing aqueous solution in which a substance having a reducing action on palladium ions coexists. Specific examples thereof include a mixed catalyst solution of palladium chloride and stannous chloride used in a pre-process of electroless plating, a waste liquid thereof, and washing wastewater generated in a pre-process of electroless plating.

【0011】塩化パラジウムと塩化第一すず混合触媒液
では、下記(I)の化学式に示される反応により、対象
物品の下地表面にパラジウム金属核ができると考えられ
ており、このすずイオンの還元力で、混合触媒液中のパ
ラジウムは、原子価が0価近くまで還元され、コロイド
粒子として存在していると考えられている。
It is believed that a palladium metal nucleus is formed on a base surface of a target article by a reaction represented by the following chemical formula (I) in a mixed catalyst solution of palladium chloride and stannous chloride. Thus, it is considered that palladium in the mixed catalyst solution is reduced to a valence of nearly zero and exists as colloid particles.

【0012】[0012]

【化1】 Sn2++Pd2+ → Sn4+ + Pd(金属核)Embedded image Sn 2+ + Pd 2+ → Sn 4+ + Pd (metal nucleus)

【0013】本発明方法において酸化処理とは、パラジ
ウム含有水溶液中のすずイオンによって保護された原子
価が0に近いコロイド粒子状のパラジウムの保護イオン
を破壊して、パラジウム金属粒子に変えることをいう。
この酸化処理は、適当な酸化剤の添加による他に、電気
化学的に酸化してもよい。
In the method of the present invention, the term "oxidation treatment" means that the protective ion of palladium in the form of colloidal particles protected by tin ions in an aqueous solution containing palladium is destroyed and converted into palladium metal particles. .
This oxidation treatment may be performed by electrochemical oxidation other than by adding an appropriate oxidizing agent.

【0014】パラジウム含有水溶液について酸化処理す
る際に使用できる酸化剤としては、例えば、空気、酸
素、過酸化水素などの酸素系酸化剤、過塩素酸塩や気体
塩素などの塩素系酸化剤、三価の鉄イオンのような金属
化合物などが挙げられる。これらは、単独でも複数の酸
化剤を併用することもできる。
Examples of the oxidizing agent that can be used when oxidizing the aqueous solution containing palladium include oxygen-based oxidizing agents such as air, oxygen, and hydrogen peroxide; chlorine-based oxidizing agents such as perchlorate and gaseous chlorine; Metal compounds such as valent iron ions are exemplified. These may be used alone or in combination of a plurality of oxidizing agents.

【0015】これらの酸化剤は、その添加量が多いと、
保護コロイドの破壊にとどまらず、パラジウムを2価の
イオンまで酸化してしまうのでパラジウムの回収ができ
なくなるので、後述するように酸化状態を確認しながら
添加するのが望ましい。
When these oxidizing agents are added in large amounts,
In addition to destruction of the protective colloid, palladium is oxidized to divalent ions, so that palladium cannot be recovered. Therefore, it is desirable to add palladium while checking the oxidation state as described later.

【0016】酸化剤として空気や酸素などの気体を用い
る場合には、通常は、室温で、気体を微細な状態でパラ
ジウム含有水溶液に吹き込むことが望ましい。吹き込み
速度および時間は、任意に設定できるが、空気の場合
は、通常、1リットルの水溶液に3リットル/分の速度
で約1時間吹き込むことにより、保護コロイドを破壊で
きる。
When a gas such as air or oxygen is used as the oxidizing agent, it is usually desirable to blow the gas into a palladium-containing aqueous solution in a fine state at room temperature. The blowing speed and time can be arbitrarily set, but in the case of air, the protective colloid can be broken usually by blowing into a 1 liter aqueous solution at a rate of 3 liter / minute for about 1 hour.

【0017】本発明方法によってパラジウム含有水溶液
からパラジウムを回収する場合に、酸化状態を確認しな
がら酸化処理を行うには、パラジウム含有水溶液の酸化
還元電位の変化により酸化処理の終点を判定する。すな
わち、酸化処理開始後、該パラジウム含有水の酸化還元
電位はほぼ一定の値を維持するが、酸化処理の進行によ
り、約300mV(対SCE)程度上昇し、その値で安
定する。本発明においては、この酸化還元電位が実質的
に上昇しはじめた時点で酸化処理を停止する。酸化還元
電位が実質的に上昇しはじめた時点の判定方法として
は、例えば、あらかじめ少量の試料について酸化処理を
行い酸化還元電位の変化を測定し、その変化量の2〜1
0%程度の上昇を検知した時点を終点とするような簡易
的な方法や、酸化還元電位の変化率を測定し、一定の上
昇率を検知した時点を終点とする方法等を採用できる。
In the case of recovering palladium from an aqueous solution containing palladium by the method of the present invention, in order to carry out the oxidation treatment while confirming the oxidation state, the end point of the oxidation treatment is determined by a change in the oxidation-reduction potential of the aqueous solution containing palladium. That is, the oxidation-reduction potential of the palladium-containing water is maintained at a substantially constant value after the start of the oxidation treatment, but is increased by about 300 mV (vs. SCE) by the progress of the oxidation treatment, and is stabilized at that value. In the present invention, the oxidation treatment is stopped when the oxidation-reduction potential starts to substantially increase. As a method of judging when the oxidation-reduction potential has substantially started to increase, for example, a small amount of a sample is subjected to an oxidation treatment in advance to measure a change in the oxidation-reduction potential, and the amount of the change is 2 to 1
A simple method in which the time when a rise of about 0% is detected is regarded as an end point, a method in which the rate of change in oxidation-reduction potential is measured, and a time when a constant rise rate is detected is regarded as an end point, or the like can be adopted.

【0018】[0018]

【実施例】以下、本発明を実施例によりさらに詳細に説
明するが、本発明は、その趣旨を超えない限り、以下の
記載例に限定されるものではない。なお、実施例中にお
いて、「%」とは特に記載のない限り「重量%」を意味
する。
EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following description unless it exceeds the gist. In Examples, “%” means “% by weight” unless otherwise specified.

【0019】[実施例1][Example 1]

【0020】パラジウム含有触媒回収模擬液の酸化処理
による酸化還元電位の変化 主たる成分が塩化第一すずと塩化パラジウムからなるパ
ラジウム含有触媒回収模擬液{Pd20ppm、Sn2
200ppm(0.0185M)、塩酸酸性でpHは
1.0である。}1リットルに対し、酸化還元電位を測
定しながら、3リットル/分の速度で空気を吹き込み酸
化処理を行った。酸化処理開始時の酸化還元電位は、約
80mV(対SCE)であり、90分間酸化処理を継続
したところ、酸化還元電位は上昇し、約410mVにな
った。このときのパラジウム含有触媒回収模擬液は、茶
褐色の濁度の高いコロイド液から、橙色の透明な水溶液
に変化した。このときの酸化還元電位の変化を図1に示
した。
Change in oxidation-reduction potential of the simulation liquid for recovery of palladium-containing catalyst due to oxidation treatment The simulation liquid for recovery of palladium-containing catalyst whose main components consist of stannous chloride and palladium chloride @Pd 20 ppm, Sn2
200 ppm (0.0185 M), hydrochloric acid acidity, pH 1.0. Air was blown at a rate of 3 liters / minute to measure the oxidation-reduction potential of 1 liter, and oxidation treatment was performed. The oxidation-reduction potential at the start of the oxidation treatment was about 80 mV (vs. SCE). When the oxidation treatment was continued for 90 minutes, the oxidation-reduction potential increased to about 410 mV. At this time, the palladium-containing catalyst recovery simulation solution changed from a brownish colloid having a high turbidity to an orange transparent aqueous solution. FIG. 1 shows the change in the oxidation-reduction potential at this time.

【0021】[実施例2] パラジウム含有触媒回収模擬液からのパラジウム回収 上記実施例1と同じパラジウム含有触媒回収模擬液を同
様にして空気により酸化処理を行い、酸化還元電位が上
昇を始める時点(73分経過時)で、酸化処理を停止し
て、触媒液を一夜放置し、生成した沈殿を濾別して回収
した。この沈殿を粉末X線回折により分析したところ、
パラジウム金属であることが確認でき、回収率は95%
であった。また、濾液中のパラジウムイオン濃度をIC
P原子発光分光法(以下、IPC−AESという。)で
測定したところ、3ppmであった。
Example 2 Recovery of Palladium from Simulated Palladium-Containing Catalyst Recovery Solution The same palladium-containing catalyst recovery simulation solution as in Example 1 was subjected to oxidation treatment with air in the same manner as above, and the point at which the oxidation-reduction potential began to rise ( At 73 minutes), the oxidation treatment was stopped, the catalyst solution was allowed to stand overnight, and the formed precipitate was collected by filtration. When this precipitate was analyzed by powder X-ray diffraction,
It can be confirmed that it is palladium metal, and the recovery rate is 95%
Met. Also, the concentration of palladium ion in the filtrate was determined by IC
It was 3 ppm when measured by P atomic emission spectroscopy (hereinafter, referred to as IPC-AES).

【0022】[比較例2]実施例2と同じパラジウム含
有触媒回収模擬液を同様にして空気による酸化処理を3
0分間行い、酸化還元電位が上昇する前に停止し、該触
媒液を一夜放置したが、実施例2のような沈殿は生成し
なかった。
COMPARATIVE EXAMPLE 2 The same palladium-containing catalyst recovery simulating liquid as in Example 2 was subjected to oxidation treatment with air in the same manner as in Example 2.
The reaction was performed for 0 minutes, stopped before the oxidation-reduction potential increased, and the catalyst solution was left overnight, but no precipitate was formed as in Example 2.

【0023】[比較例3]実施例1と同じパラジウム含
有触媒回収模擬液を同様にして空気による酸化処理を1
20分間行い、酸化還元電位が420mVまで上昇した
触媒液を一夜放置したが、実施例2のような沈殿は生成
しなかった。
Comparative Example 3 The same palladium-containing catalyst recovery simulating liquid as in Example 1 was subjected to oxidation treatment with air in the same manner as in Example 1.
The reaction was performed for 20 minutes, and the catalyst solution in which the oxidation-reduction potential was increased to 420 mV was left overnight, but no precipitate as in Example 2 was formed.

【0024】[0024]

【発明の効果】本発明は、以上詳細に説明した通りであ
り、次の様な特別に優れた効果を奏し、その産業上の利
用価値は極めて大である。 1.本発明に係る方法によるときは、パラジウムイオン
に対して還元作用を有する物質が共存するパラジウム含
有水溶液に、酸化処理を施すことにより、パラジウムを
金属として、効率よく回収することができる。 2.本発明に係る方法によるときは、パラジウムイオン
に対して還元作用を有するすずが多量に共存するにも拘
らず、貴金属であるパラジウムのみを高い選択率で完全
に分離回収することができ、貴重な資源を再利用するこ
とができる。 3.本発明に係る方法によるときは、酸化処理の終点を
酸化還元電位の変化で判定することができ、酸化処理を
自動化でき、パラジウム含有水溶液の処理を省力化して
遂行することができる。
As described in detail above, the present invention has the following particularly excellent effects, and its industrial utility value is extremely large. 1. According to the method of the present invention, palladium can be efficiently recovered as a metal by subjecting an aqueous solution of palladium containing a substance having a reducing action to palladium ions to oxidation treatment. 2. According to the method of the present invention, even though tin having a reducing action on palladium ions coexists in a large amount, it is possible to completely separate and recover only palladium, which is a noble metal, with a high selectivity, and is valuable. Resources can be reused. 3. According to the method of the present invention, the end point of the oxidation treatment can be determined by a change in the oxidation-reduction potential, the oxidation treatment can be automated, and the treatment of the aqueous solution containing palladium can be performed with reduced labor.

【図面の簡単な説明】[Brief description of the drawings]

【図1】 本発明方法を実施する際の触媒液の酸化還元
電位の変化を示している。
FIG. 1 shows a change in oxidation-reduction potential of a catalyst solution when the method of the present invention is performed.

───────────────────────────────────────────────────── フロントページの続き (72)発明者 木村 敏行 神奈川県川崎市川崎区千鳥町1番2号 川 崎化成工業株式会社内 Fターム(参考) 4D038 AA08 AB76 AB78 BA06 BB13 BB16 4D050 AA13 AB65 BB01 BB05 BB07 BB09 BD08 CA13 4K001 AA24 AA41 BA19 BA21 DB17 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshiyuki Kimura 1-2-2 Chidoricho, Kawasaki-ku, Kawasaki-shi, Kanagawa F-term in Kawasaki Chemical Industry Co., Ltd. 4D038 AA08 AB76 AB78 BA06 BB13 BB16 4D050 AA13 AB65 BB01 BB05 BB07 BB09 BD08 CA13 4K001 AA24 AA41 BA19 BA21 DB17

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 パラジウムイオンに対して還元作用を有
する物質が共存しているパラジウム含有水溶液をpH1
以下の条件で酸化処理し、その水溶液の酸化還元電位が
実質的に上昇しはじめた時点で酸化処理を停止すること
により、パラジウム金属の沈殿を生成させ、その沈殿を
分離回収することにより、パラジウムを回収する方法。
1. A palladium-containing aqueous solution in which a substance having a reducing action on palladium ions is present at pH 1
Oxidation treatment is performed under the following conditions, and when the oxidation-reduction potential of the aqueous solution starts to substantially increase, the oxidation treatment is stopped, whereby a precipitate of palladium metal is generated, and the precipitate is separated and collected. How to collect.
【請求項2】 パラジウム含有水溶液が、パラジウムと
すずとの混合触媒液の廃液である、請求項1記載のパラ
ジウムの回収方法。
2. The method for recovering palladium according to claim 1, wherein the aqueous solution containing palladium is a waste liquid of a mixed catalyst liquid of palladium and tin.
【請求項3】 還元作用を有する物質が、塩化第一すず
である、請求項1記載のパラジウムの回収方法。
3. The method for recovering palladium according to claim 1, wherein the substance having a reducing action is stannous chloride.
JP33328198A 1998-11-24 1998-11-24 Method recovering palladium Pending JP2000157983A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP33328198A JP2000157983A (en) 1998-11-24 1998-11-24 Method recovering palladium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP33328198A JP2000157983A (en) 1998-11-24 1998-11-24 Method recovering palladium

Publications (1)

Publication Number Publication Date
JP2000157983A true JP2000157983A (en) 2000-06-13

Family

ID=18264351

Family Applications (1)

Application Number Title Priority Date Filing Date
JP33328198A Pending JP2000157983A (en) 1998-11-24 1998-11-24 Method recovering palladium

Country Status (1)

Country Link
JP (1) JP2000157983A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002061156A1 (en) * 2001-02-01 2002-08-08 Kawasaki Kasei Chemicals Ltd. Method for separating, enriching and recovering palladium
WO2006030936A1 (en) * 2004-09-13 2006-03-23 Takeda Pharmaceutical Company Limited Method and apparatus for producing oxidized compound

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002061156A1 (en) * 2001-02-01 2002-08-08 Kawasaki Kasei Chemicals Ltd. Method for separating, enriching and recovering palladium
WO2006030936A1 (en) * 2004-09-13 2006-03-23 Takeda Pharmaceutical Company Limited Method and apparatus for producing oxidized compound
JPWO2006030936A1 (en) * 2004-09-13 2008-05-15 武田薬品工業株式会社 Method and apparatus for producing oxide compound
JP5173191B2 (en) * 2004-09-13 2013-03-27 武田薬品工業株式会社 Method and apparatus for producing oxide compound
KR101276915B1 (en) 2004-09-13 2013-06-19 다케다 야쿠힌 고교 가부시키가이샤 Method and apparatus for producing oxidized compound
US8592598B2 (en) 2004-09-13 2013-11-26 Takeda Pharmaceutical Company Limited Method of producing a crystal of an imidazole compound
US9346783B2 (en) 2004-09-13 2016-05-24 Takeda Pharmaceutical Company Limited Method and apparatus for producing oxidized compound

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