JP2619893B2 - Precious metal recovery method - Google Patents
Precious metal recovery methodInfo
- Publication number
- JP2619893B2 JP2619893B2 JP409188A JP409188A JP2619893B2 JP 2619893 B2 JP2619893 B2 JP 2619893B2 JP 409188 A JP409188 A JP 409188A JP 409188 A JP409188 A JP 409188A JP 2619893 B2 JP2619893 B2 JP 2619893B2
- Authority
- JP
- Japan
- Prior art keywords
- gold
- noble metal
- waste liquid
- iodine
- silver
- 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.)
- Expired - Lifetime
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
Landscapes
- Manufacture And Refinement Of Metals (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は貴金属の回収方法に関するものである。The present invention relates to a method for recovering precious metals.
（従来の技術とその問題点） ヨウ素を含む貴金属含有廃液は、貴金属をヨウ素を含
むエッチング液でエッチングしたりヨウ素溶解液で溶解
する工程より排出され、半導体産業や貴金属に関連する
事業所などに多岐にわたっている。貴金属は高価な稀少
な材料であるので、こうしたヨウ素を含む貴金属含有廃
液から貴金属を回収することは非常に重要なことであ
る。(Conventional technology and its problems) Waste liquid containing noble metal containing iodine is discharged from the process of etching the noble metal with an etching solution containing iodine or dissolving it with an iodine dissolving solution, and is sent to the semiconductor industry and offices related to noble metals. It is diverse. Since noble metals are expensive rare materials, it is very important to recover noble metals from such noble metal-containing waste liquids containing iodine.
従来のヨウ素を含む貴金属含有廃液は、金が含まれる
ことが多く、主な回収すべき貴金属は金であったが、近
年では使用材料の多様化に伴い、銀やパラジウム、白金
など、金の他に金以外の貴金属が含まれるようになって
きている。Conventional noble metal-containing waste liquid containing iodine often contains gold, and the main precious metal to be recovered was gold.In recent years, with the diversification of materials used, gold, such as silver, palladium, and platinum, has been In addition, precious metals other than gold have been included.
こうしたヨウ素を含む貴金属含有廃液より金と金以外
の貴金属を回収するには、ヒドラジンや水素化ホウ素ナ
トリウムなどの還元剤により貴金属を還元析出させるの
が一般的であるが、還元剤により貴金属が同時に析出し
てしまうので、貴金属は金と他の貴金属が混じった形状
で得られ、その後の貴金属の分離精製操作に手間がかか
るといった問題点があった。またヨウ素を含む貴金属含
有廃液にふくまれている遊離ヨウ素成分（I2及びI3 -）
をすべて分解した後でないと貴金属が析出してこないの
で多量の還元剤を使用しないと貴金属を回収することが
できないといった問題点があった。In order to recover gold and precious metals other than gold from the precious metal-containing waste liquid containing iodine, it is common to reduce and deposit the precious metals with a reducing agent such as hydrazine or sodium borohydride. Since the noble metal is precipitated, the noble metal is obtained in a form in which gold and another noble metal are mixed, and there is a problem in that the operation of separating and refining the noble metal takes time. The free iodine component that is contained in the precious metal-containing waste containing iodine (I 2 and I 3 -)
Since noble metals do not precipitate unless all of these are decomposed, there is a problem that noble metals cannot be recovered unless a large amount of reducing agent is used.
（発明が解決しようとする問題点） 本発明はこうした問題点に鑑みてなされたもので、ヨ
ウ素を含む貴金属含有廃液より金と金以外の貴金属を回
収するに際し、遊離ヨウ素成分の分解に多量の還元剤を
必要とせず、析出した貴金属の分解精製操作に手間のか
からない貴金属の回収方法を提供せんとするものであ
る。(Problems to be Solved by the Invention) The present invention has been made in view of such problems, and when recovering gold and precious metal other than gold from a waste liquid containing precious metal containing iodine, a large amount of decomposition of free iodine component is required. An object of the present invention is to provide a method for recovering a noble metal which does not require a reducing agent and does not require a troublesome operation for decomposing and refining the deposited noble metal.
（問題点を解決するための手段） 上述のごとく本発明による貴金属の回収方法は、遊離
ヨウ素を含む貴金属含有廃液より金と金以外の貴金属を
分離回収するに際し、 ａ）．該遊離ヨウ素を含む貴金属含有廃液のpHを12以上
の強アルカリ性として遊離ヨウ素をヨウ素酸イオンに変
換して該貴金属が有廃液中の金を選択的に析出させ、 ｂ）．析出した金と金析出後の前記貴金属含有廃液とを
分離し、 ｃ）．分離した該金析出後の貴金属含有廃液をさらに化
学還元剤及び／または電解により残る貴金属を析出させ
金と他の貴金属を分離回収することを特徴とするもので
ある。(Means for Solving the Problems) As described above, the method for recovering a noble metal according to the present invention includes the steps of separating and recovering gold and a noble metal other than gold from a noble metal-containing waste liquid containing free iodine: a). The pH of the waste liquid containing noble metal containing free iodine is adjusted to a strong alkalinity of 12 or more to convert free iodine to iodate ions, whereby the noble metal selectively precipitates gold in the waste liquid, b). Separating the deposited gold and the noble metal-containing waste liquid after the gold deposition, c). The separated noble metal-containing waste liquid after gold deposition is further deposited with a chemical reducing agent and / or electrolysis to separate and recover gold and other noble metals.
（作用） 以下本発明の作用についてのべる。(Action) The action of the present invention will be described below.
ヨウ素を含む貴金属含有廃液としては、半導体産業な
どで貴金属のエッチングに使用されるヨウ素エッチング
廃液や、貴金属化合物や貴金属の回収、精製に伴う廃液
などがある。含まれる貴金属としては、金、銀、白金、
パラジウムなどがあり、稀には他の貴金属がふくまれて
いる。Examples of the waste liquid containing a noble metal containing iodine include an iodine etching waste liquid used for etching a noble metal in the semiconductor industry and the like, and a waste liquid accompanying the recovery and purification of a noble metal compound and a noble metal. Precious metals included include gold, silver, platinum,
There are palladium and other rare metals.
該ヨウ素を含む貴金属含有廃液のpHを12以上の強アル
カリ性とすると、貴金属含有廃液中の貴金属のうち金が
選択的に析出し（１式） 2AuI4 -＋6OH-→2Au＋IO3 -＋7I- １式 ヨウ素を含
む貴金属含有廃液に含まれている貴金属を溶かす能力を
有する遊離ヨウ素成分（I2及びI3 -）は、ヨウ素の不均
化反応によりヨウ素酸イオンとヨウ素イオンとになり
（２式）、強アルカリ性であることも関与して貴金属を
溶かす能力を失う。When 12 or more strongly alkaline pH of the noble metal-containing waste liquid containing the iodine, of gold noble of the noble metal-containing waste liquid is selectively precipitated (1 formula) 2AuI 4 - + 6OH - → 2Au + IO 3 - + 7I - 1 formula Free iodine components (I 2 and I 3 − ) having the ability to dissolve noble metals contained in the noble metal-containing waste liquid containing iodine are converted into iodate ions and iodine ions by the disproportionation reaction of iodine (formula 2). In addition, it loses its ability to dissolve noble metals due to its strong alkaline nature.
3I2＋6OH-→IO3 -＋5I- ２式 析出した金
は貴金属含有廃液より分離することにより金を回収する
ことができる。 3I 2 + 6OH - → IO 3 - + 5I - the two money deposited expression can be recovered gold by separating from the precious metal-containing waste liquid.
貴金属含有廃液のpHが12以下であると１式の反応が起
こらず、金を析出させることができない。また２式の反
応も起こらないので該貴金属を酸化し溶かす能力のある
遊離ヨウ素成分が貴金属含有廃液中に存在してしまう。
金を析出する条件としては、pH＝12以上であればよいが
好ましくは 12.5〜14.5の範囲である。If the pH of the noble metal-containing waste liquid is 12 or less, no reaction of the type 1 occurs, and gold cannot be deposited. Further, since the reaction of the two formulas does not occur, a free iodine component capable of oxidizing and dissolving the noble metal is present in the noble metal-containing waste liquid.
The conditions for depositing gold may be pH = 12 or more, and preferably in the range of 12.5 to 14.5.
この操作により比較的品位の高い金を得ることがで
き、元のヨウ素を含む貴金属含有廃液の各貴金属の濃度
割合や種類にもよるが、その品位はおおむね95％以上で
ある。By this operation, relatively high-grade gold can be obtained, and its quality is generally 95% or more, depending on the concentration ratio and type of each noble metal in the original noble metal-containing waste liquid.
従来の操作により貴金属を回収した場合は、元のヨウ
素を含む貴金属含有廃液の各貴金属の濃度割合が、得ら
れる金の品位を決めてしまうので、金とともに他の貴金
属が多く含まれる場合には精製操作を数回繰り返し行う
必要が生じるが、本発明では他の貴金属成分の割合が多
くても金を選択的に析出させることができ、金の品位の
高いものが得られるので、次工程での金の精製操作の手
間が少なくなる。When precious metals are recovered by conventional operations, the concentration ratio of each noble metal in the precious metal-containing waste liquid containing the original iodine determines the quality of the obtained gold. Although it is necessary to repeat the refining operation several times, in the present invention, gold can be selectively precipitated even when the ratio of other noble metal components is large, and a high-quality gold can be obtained. The labor for refining gold is reduced.
該分離後の貴金属含有廃液中の貴金属は、化学還元剤
及び／または電解により析出させ回収する。The noble metal in the noble metal-containing waste liquid after the separation is precipitated and recovered by a chemical reducing agent and / or electrolysis.
化学還元剤としては、前述のヒドラジンや水素化ホウ
素ナトリウムなどのほかに、マグネシウムやアルミニウ
ム、亜鉛末などの金属還元剤など多くのものがあるが、
当該貴金属含有廃液のpHを12以上としてあるので、その
条件で貴金属を還元する能力のあるものならば特に問題
はない。また電解により陰極に貴金属を析出させてもよ
く、以上の操作により残る貴金属を回収することができ
る。As the chemical reducing agent, in addition to the above-described hydrazine and sodium borohydride, there are many such as magnesium, aluminum, and metal reducing agents such as zinc powder.
Since the pH of the waste liquid containing the noble metal is set to 12 or more, there is no particular problem as long as the waste liquid can reduce the noble metal under these conditions. The noble metal may be deposited on the cathode by electrolysis, and the remaining noble metal can be recovered by the above operation.
pH12以下の条件では、ヨウ素を含む貴金属含有廃液に
含まれている遊離ヨウ素成分（I2及びI3 -）を、全て分
解した後でないと貴金属が析出してこないが、本発明で
は、金を析出させる際の操作で予めpH12以上の強アルカ
リ性に調整してあるので、遊離ヨウ素酸成分は、２式に
従いヨウ素イオンとなり貴金属を酸化する能力を失う。
また酸化還元電位が変化し、貴金属が析出してこないと
ヨウ素酸が分解されなくなるので、還元剤を加えた際
は、貴金属の析出の後、ヨウ素酸の分解も一部おこる。
実際の反応では、貴金属の析出と共にヨウ素酸の分解も
一部おこるが、従来のように全ての遊離ヨウ素成分を分
解させる必要がなく、本発明では全てのヨウ素酸塩が分
解されなくとも貴金属を析出、回収することができるの
で、薬品効率や電気効率が向上する。Under the condition of pH 12 or less, noble metal will not be deposited unless all free iodine components (I 2 and I 3 − ) contained in the noble metal-containing waste liquid containing iodine are decomposed. Since the pH is adjusted to pH 12 or higher in advance in the operation for precipitation, the free iodic acid component becomes iodide ions according to the formula (2) and loses the ability to oxidize noble metals.
In addition, the oxidation-reduction potential changes, and iodic acid is not decomposed unless the noble metal is precipitated. Therefore, when the reducing agent is added, the iodic acid partially decomposes after the precipitation of the noble metal.
In the actual reaction, iodic acid is partially decomposed together with the precipitation of the noble metal, but it is not necessary to decompose all free iodine components as in the past, and in the present invention, noble metal is decomposed even if not all iodate is decomposed. Since it can be deposited and recovered, chemical efficiency and electric efficiency are improved.
還元剤の使用に伴いpHが下がったりすることがあり、
12以下になると薬品の使用量が増加する。従って貴金属
の還元、析出は12を下回らないpHが良く、好ましくは1
2.5〜14.5の範囲の条件下で行い、その条件はアルカリ
規定度に換算すると 0.03〜3Nである。The pH may decrease with the use of the reducing agent,
When it is less than 12, the usage of chemicals increases. Therefore, the reduction and precipitation of the noble metal should have a pH not lower than 12, preferably 1
It is carried out under the condition of 2.5 to 14.5, and the condition is 0.03 to 3N in terms of alkali normality.
（実施例１） 貴金属を含有するヨウ素エッチング廃液（金:8.7g/
、銀2.2g/、遊離ヨウ素としての酸化還元規定度:0.
24N、総ヨウ素濃度:225g/、pH＝8.5）155に水酸化
ナトリウムのフレークを撹拌しながら5kg加えてpH13.4
として金を析出させた。30分間の撹拌後、析出した金と
金析出後のヨウ素エッチング廃液とを分離した。(Example 1) Iodine etching waste liquid containing noble metal (gold: 8.7 g /
, Silver 2.2 g /, redox normality as free iodine: 0.
24N, total iodine concentration: 225 g /, pH = 8.5) 5 kg of 155 was added with flakes of sodium hydroxide while stirring, and pH 13.4
Was deposited as gold. After stirring for 30 minutes, the deposited gold was separated from the iodine etching waste liquid after the gold deposition.
析出した金は洗浄乾燥し分析したところ、金として12
74.0gが回収され、品位は99.6％と純金に近い物であっ
た。また残る0.4％はほとんどが銀であった。The deposited gold was washed, dried, and analyzed.
74.0g was recovered, and the grade was 99.6%, almost pure gold. The remaining 0.4% was mostly silver.
金析出後のヨウ素エッチング廃液は、固液分離操作の
結果液量が155から162に増加したので、分析をした
ところ金:0.46g/、銀:2.1g/になり、ヨウ素酸イオ
ンとしての酸化還元規定度は、以前より有していた遊離
ヨウ素としての酸化還元規定度のほかに、金を析出した
際に精製するヨウ素酸イオン分が加わり、0.35Nに増加
した。Since the liquid volume of the iodine etching waste liquid after gold deposition increased from 155 to 162 as a result of the solid-liquid separation operation, it was analyzed to be 0.46 g / gold, 2.1 g / silver, and oxidized as iodate ions. The reduction normality increased to 0.35 N due to the addition of the iodate ion which was purified when gold was deposited, in addition to the redox normality as free iodine which had been previously possessed.
当該金析出後のヨウ素エッチング廃液中（0.35N×162
＝56.7当量：ヨウ素酸の酸化還元当量） の銀と未反応の金（計4.3当量分）を回収するために、
亜鉛末を500g（15.3当量分）加えてよく撹拌した。水素
ガスの発生と共に金と銀が析出し、約１時間後に撹拌を
止めて、金と銀を濾過により分離して回収したが、ヨウ
素酸の分解に必要な還元剤の当量以下で貴金属を回収す
ることができた。In the iodine etching waste liquid after the gold deposition (0.35N × 162
= 56.7 equivalents: redox equivalents of iodic acid) to recover unreacted silver (4.3 equivalents in total)
500 g (15.3 equivalents) of zinc dust was added and stirred well. Gold and silver were precipitated with the generation of hydrogen gas. After about 1 hour, stirring was stopped, and gold and silver were separated and recovered by filtration. We were able to.
析出した金と銀は洗浄乾燥し、分析したところ、総重
量416.9gに対して、金が18.0％、銀が80.5％、亜鉛後の
不純物が1.5％含まれており、金として75.1g、銀として
335.5gが回収された。The deposited gold and silver were washed, dried and analyzed. The total weight was 416.9 g, which contained 18.0% of gold, 80.5% of silver, and 1.5% of impurities after zinc. As
335.5 g were recovered.
回収した金銀は金の割合が低いので、うち400gに硝酸
1.2を加えて、そのまま硝酸分金法により金と銀に分
離したところ、純金と硝酸銀の溶液とに容易に分離する
ことができた。The recovered gold and silver have a low percentage of gold.
When 1.2 was added and the mixture was separated into gold and silver by the nitric acid metallurgical method as it was, it could be easily separated into a solution of pure gold and silver nitrate.
（従来例１） 貴金属を含有するヨウ素エッチング廃液（金:8.7g/
、銀:2.2g/、遊離ヨウ素としての酸化還元規定度:
0.24N、総ヨウ素濃度:255g/、pH＝8.5）10に水加ヒ
ドラジンを加えて貴金属を還元した。遊離ヨウ素を分解
するに必要な酸化還元当量の2.4当量（0.24N×10＝2.
4当量）と金と銀を回収するために必要な1.5当量とを合
計した3.9当量の1.2倍に相当する4.68当量の水加ヒドラ
ジンを加えたにもかからわず貴金属を全て還元すること
ができなかったので、さらに2.34当量を加えて当該貴金
属を含有するヨウ素エッチング廃液中の金銀を還元、析
出させた。析出した金と銀は濾過、洗浄、乾燥の後、分
析したところ、総重量109.1gに対して、金が79.8％、銀
が19.8％、その他の不純物が0.4％含まれており、金と
して87.1g、銀として21.6gが回収された。(Conventional example 1) Iodine etching waste liquid containing noble metal (gold: 8.7g /
, Silver: 2.2 g /, redox normality as free iodine:
0.24 N, total iodine concentration: 255 g /, pH = 8.5) 10 was added with hydrazine hydrate to reduce noble metals. 2.4 equivalents of redox equivalents required to decompose free iodine (0.24N × 10 = 2.
4 equivalents) and 1.5 equivalents required to recover gold and silver are added. 4.68 equivalents of hydrated hydrazine, equivalent to 1.2 times 3.9 equivalents, can be used to reduce all precious metals. Since it could not be performed, 2.34 equivalents were further added to reduce and precipitate gold and silver in the iodine etching waste liquid containing the noble metal. The precipitated gold and silver were filtered, washed and dried, and then analyzed. The total weight was 109.1 g, which contained 79.8% of gold, 19.8% of silver, and 0.4% of other impurities. g and 21.6 g of silver were recovered.
回収した金額は金の割合が高く、実施例１のようにそ
のまま硝酸分金法をおこなうと銀を溶かすことが出来ず
金と銀を分離することが出来なくなるので、うち100gを
とり銅を220g加えてるつぼ中で一旦融解させ、金銀銅の
合金とすることにより金の品位を25％まで下げたのち、
硝酸1.0を加えて、硝酸分金法により金と銀に分離し
たところ、純金と多量の銅が溶けた硝酸銀の溶液とに分
離することができた。The amount of gold recovered is high in the proportion of gold. If the nitric acid distribution method is used as in Example 1, silver cannot be dissolved and gold and silver cannot be separated, so 100 g of copper and 220 g of copper are used. Once melted in a crucible and then reduced to a gold grade of 25% by forming a gold-silver-copper alloy,
When nitric acid 1.0 was added and the mixture was separated into gold and silver by the nitric acid separation method, it could be separated into pure gold and a solution of silver nitrate in which a large amount of copper was dissolved.
実施例１では、アルカリを使用してほとんどの金を析
出させており、また金の品位も高いものが得られるの
で、容易に精製することができる。その後に得られる貴
金属の混合物も、前の操作によりほとんどの金を除いた
後であるので処理量が少なくてすみ、その後の分離、精
製操作が容易になる。In Example 1, most of the gold was precipitated using an alkali, and a high-quality gold was obtained, so that the gold could be easily purified. The mixture of noble metals obtained thereafter is also obtained after most of the gold has been removed by the previous operation, so that the processing amount can be reduced, and the subsequent separation and purification operations become easy.
一方従来例１では、貴金属の濃度割合によって回収さ
れた貴金属の割合が決まってしまい、金と他の貴金属の
分離に手間がかかり、実施例１での処理量に換算すると
その手間は膨大なものとなる。また還元剤の使用量も遊
離ヨウ素成分を分解した後でないと貴金属が還元、析出
してこないので、約７倍も必要であった。On the other hand, in the conventional example 1, the ratio of the recovered noble metal is determined by the concentration ratio of the noble metal, and it takes time and effort to separate gold and other noble metals. Becomes In addition, the amount of the reducing agent used was about 7 times as long as the noble metal was not reduced and precipitated unless the free iodine component was decomposed.
（実施例２） ヨウ素を含む貴金属含有廃液（金:12.5g/、銀1.2g/
、パラジウム2.6g/、白金0.4g/、pH＝5.5）10
）に水酸化カリウムを加えてpH12.9として金を析出さ
せた。30分間撹拌した後、析出した金と金析出後の上記
ヨウ素を含む貴金属廃液とを分離した。(Example 2) Noble metal-containing waste liquid containing iodine (gold: 12.5 g /, silver: 1.2 g /
, 2.6 g / palladium, 0.4 g / platinum, pH = 5.5) 10
) Was adjusted to pH 12.9 with potassium hydroxide to precipitate gold. After stirring for 30 minutes, the deposited gold and the precious metal waste liquid containing iodine after the gold deposition were separated.
析出した金は、洗浄乾燥し、分析したところ、金とし
て113.5gが回収され、品位は97.5％と純金に近いもので
あった。また残る2.5％はほとんどが銀とパラジウムで
あった。The deposited gold was washed, dried, and analyzed. As a result, 113.5 g of gold was recovered, and the quality was 97.5%, which was close to pure gold. The remaining 2.5% was mostly silver and palladium.
金析出後の貴金属廃液は、陽極に10cm×20cmの白金メ
ッキしたチタン板、陰極に10cm×20cmのステンレス板
（SUS316）を使用して、10Aで４時間電解して、陰極に
貴金属を析出させた。電解中に液のpHが下がったので水
酸化カリウムでpHを13.2に調整した。The noble metal waste liquid after gold deposition is electrolyzed at 10A for 4 hours using a 10cm x 20cm platinum-plated titanium plate for the anode and a 10cm x 20cm stainless steel plate (SUS316) for the cathode to precipitate the noble metal on the cathode. Was. Since the pH of the solution dropped during electrolysis, the pH was adjusted to 13.2 with potassium hydroxide.
陰極に析出した貴金属を分析したところ、金が11.7
g、銀が9.6g、パラジウムが25.1g、白金が3.9g含まれて
いたが重金属はほとんど含まれていなかった。Analysis of the noble metal deposited on the cathode revealed that gold was 11.7
g, 9.6 g of silver, 25.1 g of palladium, and 3.9 g of platinum, but hardly any heavy metals.
（従来例２） ヨウ素を含む貴金属廃液（金:12.5g/、銀:1.2g/
、パラジウム:2.6g/、白金:0.4g/、pH＝5.5）５
を、陽極と陰極に10cm×20cmの白金メッキしたチタン
板を使用して、10Aで４時間電解したところ、貴金属が
析出するものの、一旦析出した貴金属が電解より剥離し
て再び液中に溶解してしまうので、貴金属を回収するこ
とはできなかった。(Conventional example 2) Noble metal waste liquid containing iodine (gold: 12.5 g /, silver: 1.2 g /
, Palladium: 2.6 g /, platinum: 0.4 g /, pH = 5.5) 5
Was electrolyzed at 10 A for 4 hours using a 10 cm x 20 cm platinum-plated titanium plate on the anode and cathode, but the noble metal was deposited, but the deposited noble metal was peeled off from the electrolysis and dissolved in the liquid again. So no precious metals could be recovered.
（発明の効果） 本発明はヨウ素を含む貴金属含有廃液より金と金以外
の貴金属を分離回収するに際し、まずヨウ素を含む貴金
属含有廃液のpHを12以上の強アルカリ性として該貴金属
含有廃液中の金を選択的に析出させ、ついで析出した金
と金析出後の貴金属含有廃液を分離し、分離した金析出
後の貴金属含有廃液をさらに化学還元剤及び／または電
解により残る貴金属を析出させることにより金と他の貴
金属を回収できるようにしている。あらかじめ金を分離
しておくことにより、その後の貴金属を分離、精製操作
が非常に容易になるとともに、強アルカリ性にて反応さ
せることにより貴金属の回収に多量の還元剤を必要とし
なくなるなどの効果がある。この結果、回収、精製にか
かるコストが大幅に改善されるなどの別の効果もあり、
貴金属のように稀少な金属を回収するうえで、産業への
貢献大なるものと言える。(Effect of the Invention) In the present invention, when separating and recovering gold and a noble metal other than gold from a noble metal-containing waste liquid containing iodine, first, the pH of the noble metal-containing waste liquid containing iodine is adjusted to a strong alkalinity of 12 or more, and the gold in the noble metal-containing waste liquid Is selectively separated, then the separated gold and the noble metal-containing waste liquid after the gold deposition are separated, and the separated noble metal-containing waste liquid after the gold deposition is further separated by a chemical reducing agent and / or electrolysis to precipitate the remaining noble metal. And other precious metals can be recovered. Separating the gold in advance makes it very easy to separate and purify the subsequent noble metal, and has the effect of eliminating the need for a large amount of reducing agent to recover the noble metal by reacting it with strong alkali. is there. As a result, there are other effects such as a significant improvement in the cost of recovery and purification,
It is a great contribution to the industry in recovering rare metals such as precious metals.
Claims (2)
金以外の貴金属を分離回収するに際し、 ａ）．該遊離ヨウ素を含む貴金属含有廃液のpHを12以上
の強アルカリ性として該遊離ヨウ素をヨウ素酸イオンに
変換して、該貴金属含有廃液中の金を選択的に析出さ
せ、 ｂ）．析出した金と金析出後の前記貴金属含有廃液とを
分離し、 ｃ）．分離した該金析出後の貴金属含有廃液をさらに化
学還元剤及び／または電解により残る貴金属を析出させ
金と他の貴金属を分離回収することを特徴とする貴金属
の回収方法。1. A method for separating and recovering gold and a noble metal other than gold from a waste liquid containing a noble metal containing free iodine: a). Converting the free iodine into iodate ions by making the pH of the noble metal-containing waste liquid containing free iodine strong alkalinity of 12 or more, and selectively depositing gold in the noble metal-containing waste liquid; b). Separating the deposited gold and the noble metal-containing waste liquid after the gold deposition, c). A method for recovering a noble metal, characterized in that the separated noble metal-containing waste liquid after the deposition of gold is further deposited with a chemical reducing agent and / or electrolysis to separate and recover gold and other noble metals.
が、銀、白金、パラジウムからなる群より選択されるこ
とを特徴とする特許請求の範囲第１項に記載の貴金属の
回収方法。2. The method for recovering a noble metal according to claim 1, wherein the noble metal other than gold contained in the noble metal-containing waste liquid is selected from the group consisting of silver, platinum, and palladium.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP409188A JP2619893B2 (en) | 1988-01-12 | 1988-01-12 | Precious metal recovery method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP409188A JP2619893B2 (en) | 1988-01-12 | 1988-01-12 | Precious metal recovery method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01180923A JPH01180923A (en) | 1989-07-18 |
| JP2619893B2 true JP2619893B2 (en) | 1997-06-11 |
Family
ID=11575124
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP409188A Expired - Lifetime JP2619893B2 (en) | 1988-01-12 | 1988-01-12 | Precious metal recovery method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2619893B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4788998B2 (en) * | 2005-12-28 | 2011-10-05 | Ｊｘ日鉱日石金属株式会社 | Method for recovering gold from etching waste liquid |
| CN110983065A (en) * | 2019-12-23 | 2020-04-10 | 昆山全亚冠环保科技有限公司 | Method for reducing gold in iodine-containing waste liquid |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3957505A (en) * | 1974-08-05 | 1976-05-18 | Bayside Refining And Chemical Company | Gold reclamation process |
| GB1533477A (en) * | 1976-05-25 | 1978-11-22 | Automated Med Syst | Removal of heavy metals from solution |
| JPS58174532A (en) * | 1982-04-05 | 1983-10-13 | Tanaka Kikinzoku Kogyo Kk | Recovery of palladium or noble metal mixed in palladium |
| JP2685755B2 (en) * | 1987-07-14 | 1997-12-03 | 田中貴金属工業株式会社 | Gold refining equipment |
-
1988
- 1988-01-12 JP JP409188A patent/JP2619893B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01180923A (en) | 1989-07-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6126720A (en) | Method for smelting noble metal | |
| JP2001316736A (en) | Method for recovering silver | |
| JPWO2005023716A1 (en) | Method for separating and purifying high-purity silver chloride and method for producing high-purity silver using the same | |
| US4445935A (en) | Method for the recovery of silver from waste photographic fixer solutions | |
| JP2619893B2 (en) | Precious metal recovery method | |
| EP1577408B2 (en) | Method for separating platinum group elements from selenum/tellurium bearing materials | |
| JP2009209421A (en) | Method for producing high purity silver | |
| CN106119567A (en) | A kind of method of gold of purifying metals | |
| JP2791161B2 (en) | Method for recovering silver from silver-containing nitric acid solution | |
| JPH06280075A (en) | Method for electrolytic extraction of highly pure platinum from platinum alloy | |
| KR100415448B1 (en) | Method of recovering silver | |
| JPS5952696B2 (en) | Method for recovering copper and selenium from copper electrolysis anode slime | |
| JPH08260065A (en) | Method for fractionating and recovering noble metal from noble metal-containing material | |
| JP2619892B2 (en) | Precious metal recovery method | |
| JP3753554B2 (en) | Silver recovery method | |
| Lee et al. | Recovery of silver and mercury from dental amalgam waste | |
| ZA200501505B (en) | Method for removal of silver from a copper chloride solution | |
| RU2176279C1 (en) | Method for processing secondary gold-containing material to pure gold | |
| JP3837879B2 (en) | Method for reducing and precipitating metal ions | |
| JP2937184B1 (en) | How to remove platinum and palladium | |
| RU2200132C1 (en) | Method of recovering and separating platinum-group metals | |
| JPH11229053A (en) | Production of high purity gold | |
| JPS5888124A (en) | Palladium purification and recovery | |
| JPS63183138A (en) | Refining method for metallic gallium | |
| US5997719A (en) | Electrochemical process for refining platinum group metals with ammonium chloride electrocyte |