EP0573743A2 - Process for electrolytic decontaminating or regenerating a cyanide containing aqueous solution and apparatus for performing this process - Google Patents
Process for electrolytic decontaminating or regenerating a cyanide containing aqueous solution and apparatus for performing this process Download PDFInfo
- Publication number
- EP0573743A2 EP0573743A2 EP93104209A EP93104209A EP0573743A2 EP 0573743 A2 EP0573743 A2 EP 0573743A2 EP 93104209 A EP93104209 A EP 93104209A EP 93104209 A EP93104209 A EP 93104209A EP 0573743 A2 EP0573743 A2 EP 0573743A2
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- Prior art keywords
- cyanide
- metal
- solution
- copper
- cathode
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D21/00—Processes for servicing or operating cells for electrolytic coating
- C25D21/16—Regeneration of process solutions
- C25D21/20—Regeneration of process solutions of rinse-solutions
Definitions
- the invention relates to a method for electrolytic detoxification or regeneration of an aqueous solution containing cyanide, wherein cyanide is converted into carbon dioxide and / or nitrogen and / or ammonia by means of anodic oxidation, and to an apparatus for carrying out the method.
- the concentration of the cyanide being greatly reduced by anodic oxidation to ammonia and, at the same time, the silver in spongy form deposited on the cathode, periodically stripped from there and collected in a funnel arranged at the bottom of the regeneration cell and filtered.
- the anode has a titanium-platinum plating, while the cathode contains a pure silver plating, so that here too the problem of the high removal rates of platinum-plated titanium electrodes arises with the consequently high consequential costs.
- the invention is based on the object of treating the high loads of cyanide wastewater occurring in the metal industry, in particular in electroplating plants, at low cost by electrochemical means, high power yields being possible even at low concentrations and further detoxification processes being unnecessary; Furthermore, a device for electrolytic detoxification or regeneration of an aqueous solution containing cyanide is to be specified; the service life of the anodes is also to be increased.
- a major advantage of the method is that, due to the high efficiency, a rapid reaction sequence is achieved, whereby both the electricity costs and the electrode costs (coating costs) can be kept relatively low.
- Another advantage is achieved by reusing the cathodically deposited metallic part from the cyanide compound.
- the invention is achieved according to the device by the characterizing features of claim 8.
- a major advantage of the device is that the anode enables a long service life due to its dimensionally stable structure and high durability of its coating. Furthermore, the size of the device and thus the system costs can be kept relatively low due to the high efficiency.
- an electrochemical cell with a solution container which has an attached cell housing in which there is an electrode packet with elongated plate-shaped electrodes arranged in parallel and spaced apart, whereby the anodes are in the middle and the cathodes are arranged at the ends.
- the cathode consists of an expanded metal grid made of copper-plated titanium (copper surface), while the anode is designed as a dimensionally stable anode based on titanium, the electrocatalytic coating of which consists of oxides of platinum group metals and / or titanium and of platinum group metals.
- the basic structure of such anodes is known for example from DE-PS 20 41 250.
- the volume of the Solution tank is in the range of 50-1000 l; the anodic current density is in the range of 100-2500 A / m2.
- the electrode spacing is in the range of 0.5-5 cm.
- the reaction takes place at a temperature in the range of 20-50 ° C.
- the electrolytic detoxification is carried out until a final concentration of cyanide of 0.2 mg / l and copper of 0.1 mg / l is reached.
- Example 1 When treating a solution corresponding to Example 1 with added copper in the range of 10-500 mg / l copper ions, it is also possible to carry out the first treatment phase (1st trip) with a cathode made of expanded titanium without a copper-coated surface or copper coating.
- the copper additive is added either in the form of copper sulfate (solid or dissolved) or in the form of a wastewater solution containing copper ions.
- the other process parameters of Example 1 and the known structure of the dimensionally stable anode and electrode spacing are retained.
- an electrochemical device with a dimensionally stable anode according to Examples 1 and 2 which has a cathode made of expanded copper foil.
- the electrochemical treatment is carried out until a silver ion concentration is reached which is below 0.1 mg / l; the residual cyanide concentration after the demetallization is 8.6 g / l of free cyanide ions.
- the other process parameters, such as anodic and cathodic current density, electrode spacing and temperature correspond to those of Example 1.
- the demetallized solution thus obtained can be detoxified either by the process according to Example 1 or by the process given below as Example 4.
- a silver cyanide solution with elaborated silver (silver ion concentration below 0.1 mg / l) and 8.6 g / l free cyanide is fed to a correspondingly constructed electrochemical cell, the cathode of which is made of copper-plated expanded titanium. Current density and electrode spacing as well as operating temperature are maintained in accordance with the aforementioned examples.
- the electrolytic detoxification (anodic oxidation) is carried out until a cyanide content of 0.1 mg / l can be measured.
- solution is supplied to the cell housing in the region of its housing base by means of a circulating device and, after passing through the electrode pack, is fed to a cascade-like drain container with its own overflow for degassing by means of an overflow over the side walls of the cell housing; After passing through a second overflow, the now largely degassed solution is returned to the solution tank and recirculated and subjected to an electrochemical treatment until the desired or legally prescribed residual concentration is reached.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
- Electrodes For Compound Or Non-Metal Manufacture (AREA)
- Electrolytic Production Of Metals (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
Abstract
Description
Die Erfindung betrifft ein Verfahren zur elektrolytischen Entgiftung oder Regeneration einer Cyanid enthaltenden wässrigen Lösung, wobei Cyanid mittels anodischer Oxidation in Kohlendioxid und/oder Stickstoff und/oder Ammoniak umgewandelt wird, sowie eine Vorrichtung zur Durchführung des Verfahrens.The invention relates to a method for electrolytic detoxification or regeneration of an aqueous solution containing cyanide, wherein cyanide is converted into carbon dioxide and / or nitrogen and / or ammonia by means of anodic oxidation, and to an apparatus for carrying out the method.
Aus der DE-OS 26 00 084 ist die elektrochemische Behandlung von verdünnten Metallcyanid-Lösungen, wie sie beispielsweise in Form von Waschlösungen in Galvanisierungsanstalten auftritt, bekannt, wobei Cyanid anodisch oxidiert wird unter gleichzeitiger kathodischer Metallabscheidung. Anode und Kathode sind dabei als Netze bzw. Maschenkörbe ausgebildet, wobei beide Elektroden aus platinisiertem Titan bestehen können; es ist jedoch auch möglich, eine aus Kupfer hergestellte Kathode einzusetzen. Gemäß einem Ausführungsbeispiel für die zu behandelnde Lösung sind neben Kupfercyanid auch Natriumcyanid und Natriumcarbonat sowie Rochelle-Salz als Bestandteile der Lösung angegeben.From DE-OS 26 00 084 the electrochemical treatment of dilute metal cyanide solutions, as occurs, for example, in the form of washing solutions in galvanizing plants, is known, cyanide being anodically oxidized with simultaneous cathodic metal deposition. The anode and cathode are designed as nets or mesh baskets, both electrodes being made of platinized titanium; however, it is also possible to use a cathode made of copper. According to an exemplary embodiment of the solution to be treated, sodium cyanide and sodium carbonate and Rochelle salt are also specified as constituents of the solution in addition to copper cyanide.
Als problematisch erweist sich bei der elektrolytischen Oxidation in niedrigen Konzentrationsbereichen die unbefriedigende Stromausbeute, so daß bei den üblichen strengen behördlichen Einleiterbedingungen (Umweltauflagen) der Einsatz eines weiteren Verfahrens zur Entgiftung geringer Cyanid-Konzentrationen sich als unumgänglich erweist. Weiterhin entstehen an den platinierten Titan-Elektroden hohe Abtragsraten (kurze Standzeiten), so daß das Verfahren der elektrochemischen Cyanid-Oxidation in der Praxis aufgrund der hohen Folgekosten (Anodenkosten) unter wirtschaftlicher Betrachtung wenig sinnvoll erscheint.The unsatisfactory current yield proves to be problematic in the case of electrolytic oxidation in low concentration ranges, so that the use of a further process for the detoxification of low cyanide concentrations proves to be unavoidable under the usual strict official discharge conditions (environmental regulations). Furthermore, high removal rates (short service lives) occur on the platinum-coated titanium electrodes, so that the process of electrochemical cyanide oxidation does not appear to make much sense in practice due to the high consequential costs (anode costs).
Weiterhin ist aus der DE-PS 28 36 720 ein Verfahren zur kontinuierlichen elektrolytischen Regenerierung einer Silbercyanid enthaltenden Waschlösung, wie sie bei Galvanisierungs-Prozessen anfällt, bekannt, wobei die Konzentration des Cyanid durch anodische Oxidation zu Ammoniak stark verringert und gleichzeitig das Silber in schwammiger Form auf der Kathode abgeschieden, von dort periodisch abgestreift und in einen am Boden der Regenerierzelle angeordneten Trichter gesammelt und abfiltriert wird. Gemäß einem Ausführungsbeispiel weist die Anode eine Titan-Platin-Plattierung auf, während die Kathode eine reine Silber-Plattierung enthält, so daß auch hier das Problem der hohen Abtragsraten von platinierten Titan-Elektroden mit den in der Praxis hohen Folgekosten auftritt.Furthermore, from DE-PS 28 36 720 a process for the continuous electrolytic regeneration of a washing solution containing silver cyanide, such as is obtained in electroplating processes, is known, the concentration of the cyanide being greatly reduced by anodic oxidation to ammonia and, at the same time, the silver in spongy form deposited on the cathode, periodically stripped from there and collected in a funnel arranged at the bottom of the regeneration cell and filtered. According to one exemplary embodiment, the anode has a titanium-platinum plating, while the cathode contains a pure silver plating, so that here too the problem of the high removal rates of platinum-plated titanium electrodes arises with the consequently high consequential costs.
Der Erfindung liegt die Aufgabe zugrunde, die in der Metallindustrie, insbesondere in Galvanikbetrieben anfallenden hohen Frachten an cyanidischen Abwassern auf elektrochemischem Wege kostengünstig zu behandeln, wobei auch bei niedrigen Konzentrationen hohe Stromausbeuten möglich sind und weitere Verfahren zur Entgiftung sich erübrigen; weiterhin soll eine Vorrichtung zur elektrolytischen Entgiftung oder Regeneration einer Cyanid enthaltenden wässrigen Lösung angegeben werden; weiterhin soll die Standzeit der Anoden erhöht werden.The invention is based on the object of treating the high loads of cyanide wastewater occurring in the metal industry, in particular in electroplating plants, at low cost by electrochemical means, high power yields being possible even at low concentrations and further detoxification processes being unnecessary; Furthermore, a device for electrolytic detoxification or regeneration of an aqueous solution containing cyanide is to be specified; the service life of the anodes is also to be increased.
Die Aufgabe wird verfahrensgemäß durch die kennzeichnenden Merkmale des Anspruchs 1 gelöst.The object is achieved according to the method by the characterizing features of claim 1.
Vorteilhafte Ausgestaltungen des Verfahrens sind in den Ansprüchen 2 bis 7 angegeben.Advantageous embodiments of the method are specified in claims 2 to 7.
Ein wesentlicher Vorteil des Verfahrens ist darin zu sehen, daß aufgrund des hohen Wirkungsgrades ein rascher Reaktionsablauf erzielt wird, wobei sowohl die Stromkosten als auch die Elektrodenkosten (Beschichtungskosten) verhältnismäßig gering gehalten werden können.A major advantage of the method is that, due to the high efficiency, a rapid reaction sequence is achieved, whereby both the electricity costs and the electrode costs (coating costs) can be kept relatively low.
Ein weiterer Vorteil wird durch die Wiederverwendung des kathodisch abgeschiedenen metallischen Anteils aus der Cyanid-Verbindung erzielt.Another advantage is achieved by reusing the cathodically deposited metallic part from the cyanide compound.
Die Erfindung wird vorrichtungsgemäß durch die kennzeichnenden Merkmale des Anspruchs 8 gelöst.The invention is achieved according to the device by the characterizing features of claim 8.
Bevorzugte Ausgestaltungen der Vorrichtung sind in den Ansprüchen 9 bis 15 angegeben. Der in Anspruch 10 genannte Begriff Streckmetallgitter bezieht sich auch auf eine Streckmetall-Folie.Preferred embodiments of the device are specified in claims 9 to 15. The term expanded metal mesh mentioned in claim 10 also refers to an expanded metal foil.
Ein wesentlicher Vorteil der Vorrichtung ist darin zu sehen, daß die Anode aufgrund ihrer dimensionsstabilen Struktur und hohen Beständigkeit ihrer Beschichtung eine hohe Standzeit ermöglicht. Weiterhin lassen sich aufgrund des hohen Wirkungsgrades die Baugröße der Vorrichtung und somit die Anlagenkosten verhältnismäßig gering halten.A major advantage of the device is that the anode enables a long service life due to its dimensionally stable structure and high durability of its coating. Furthermore, the size of the device and thus the system costs can be kept relatively low due to the high efficiency.
Im folgenden wird der Gegenstand der Erfindung anhand von Ausführungsbeispielen erläutert.The subject matter of the invention is explained below using exemplary embodiments.
Zur elektrochemischen Entgiftung einer rein cyanidischen Lösung mit einem Anteil von 5-100 g/l Cyanid ist eine elektrochemische Zelle mit einem Lösungsbehälter vorgesehen, der ein aufgesetztes Zellengehäuse aufweist, in dem sich ein Elektrodenpaket mit langgestreckten plattenförmigen parallel und im Abstand angeordneten Elektroden befindet, wobei die Anoden mittig und die Kathoden endständig angeordnet sind. Die Kathode besteht dabei aus einem Streckmetallgitter aus verkupfertem Titan (Kupferoberfläche), während die Anode als dimensionsstabile Anode auf der Basis von Titan ausgebildet ist, wobei deren elektrokatalytische Beschichtung aus Oxiden von Platingruppenmetallen und/oder Titan sowie aus Platingruppenmetallen besteht. Der prinzipielle Aufbau solcher Anoden ist beispielsweise aus der DE-PS 20 41 250 bekannt. Das Volumen des Lösungsbehälters liegt im Bereich von 50-1000 l; die anodische Stromdichte liegt im Bereich von 100-2500 A/m². Der Elektrodenabstand liegt im Bereich von 0,5-5 cm. Die Umsetzung erfolgt bei einer Temperatur im Bereich von 20-50°C. Die elektrolytische Entgiftung wird solange durchgeführt, bis eine Endkonzentration an Cyanid von 0,2 mg/l und an Kupfer von 0,1 mg/l erzielt ist.For the electrochemical detoxification of a purely cyanide solution with a proportion of 5-100 g / l cyanide, an electrochemical cell with a solution container is provided, which has an attached cell housing in which there is an electrode packet with elongated plate-shaped electrodes arranged in parallel and spaced apart, whereby the anodes are in the middle and the cathodes are arranged at the ends. The cathode consists of an expanded metal grid made of copper-plated titanium (copper surface), while the anode is designed as a dimensionally stable anode based on titanium, the electrocatalytic coating of which consists of oxides of platinum group metals and / or titanium and of platinum group metals. The basic structure of such anodes is known for example from DE-PS 20 41 250. The volume of the Solution tank is in the range of 50-1000 l; the anodic current density is in the range of 100-2500 A / m². The electrode spacing is in the range of 0.5-5 cm. The reaction takes place at a temperature in the range of 20-50 ° C. The electrolytic detoxification is carried out until a final concentration of cyanide of 0.2 mg / l and copper of 0.1 mg / l is reached.
Bei Behandlung einer dem Beispiel 1 entsprechenden Lösung mit Kupferzusatz im Bereich von 10-500 mg/l Kupferionen ist es auch möglich, die erste Behandlungsphase (l. Fahrt) mit einer Kathode aus Titanstreckmetall ohne verkupferte Oberfläche bzw. Kupferbeschichtung durchzuführen. Die Zugabe des Kupferzusatzes erfolgt dabei entweder in Form von Kupfersulfat (fest oder gelöst) oder in Form einer Kupfer-Ionen enthaltenden Abwasser-Lösung. Die übrigen Verfahrensparameter des Beispiels 1 sowie der daraus bekannte Aufbau der dimensionsstabilen Anode und Elektrodenabstand bleiben erhalten.When treating a solution corresponding to Example 1 with added copper in the range of 10-500 mg / l copper ions, it is also possible to carry out the first treatment phase (1st trip) with a cathode made of expanded titanium without a copper-coated surface or copper coating. The copper additive is added either in the form of copper sulfate (solid or dissolved) or in the form of a wastewater solution containing copper ions. The other process parameters of Example 1 and the known structure of the dimensionally stable anode and electrode spacing are retained.
Zur Entmetallisierung einer cyanidischen Silberlösung mit 13,5 g/l SilberIonen und 1,8 g/l freien Cyanid-Ionen wird eine elektrochemische Vorrichtung mit einer dimensionsstabilen Anode gemäß den Beispielen 1 und 2 eingesetzt, die eine Kathode aus Kupferstreckmetall-Folie aufweist. Die elektrochemische Behandlung wird dabei solange betrieben, bis eine Silber-Ionen-Konzentration erreicht ist, die unterhalb von 0,1 mg/l liegt; die Cyanid-Restkonzentration liegt nach der Entmetallisierung bei 8,6 g/l freier Cyanid-Ionen. Die übrigen Verfahrensparameter, wie anodische und kathodische Stromdichte, Elektrodenabstand und Temperatur entsprechen denen des Beispiels 1.To demetallize a cyanide silver solution with 13.5 g / l silver ions and 1.8 g / l free cyanide ions, an electrochemical device with a dimensionally stable anode according to Examples 1 and 2 is used, which has a cathode made of expanded copper foil. The electrochemical treatment is carried out until a silver ion concentration is reached which is below 0.1 mg / l; the residual cyanide concentration after the demetallization is 8.6 g / l of free cyanide ions. The other process parameters, such as anodic and cathodic current density, electrode spacing and temperature correspond to those of Example 1.
Es ist jedoch auch möglich, an Stelle einer Kupferstreckmetall-Folie eine Silberstreckmetall-Folie einzusetzen.However, it is also possible to use a silver expanded metal foil instead of a copper expanded metal foil.
Die so erhaltene entmetallisierte Lösung kann sowohl nach dem Verfahren gemäß Beispiel 1 oder nach dem nachfolgend als Beispiel 4 angegebenen Verfahren entgiftet werden.The demetallized solution thus obtained can be detoxified either by the process according to Example 1 or by the process given below as Example 4.
Es wird eine Silbercyanidlösung mit ausgearbeitetem Silber (Silber-Ionen-Konzentration unterhalb 0,1 mg/l) und 8,6 g/l freiem Cyanid einer entsprechend aufgebauten elektrochemischen Zelle zugeführt, deren Kathode aus verkupfertem Titanstreckmetall besteht. Stromdichte und Elektrodenabstand sowie Betriebstemperatur werden dabei entsprechend den vorgenannten Beispielen aufrechterhalten. Die elektrolytische Entgiftung (anodische Oxidation) wird solange durchgeführt, bis ein Cyanidgehalt von 0,1 mg/l zu messen ist.A silver cyanide solution with elaborated silver (silver ion concentration below 0.1 mg / l) and 8.6 g / l free cyanide is fed to a correspondingly constructed electrochemical cell, the cathode of which is made of copper-plated expanded titanium. Current density and electrode spacing as well as operating temperature are maintained in accordance with the aforementioned examples. The electrolytic detoxification (anodic oxidation) is carried out until a cyanide content of 0.1 mg / l can be measured.
In einer Vorrichtung zur Durchführung der Verfahren der Beispiele 1 bis 4 wird mittels Umwälzvorrichtung dem Zellengehäuse im Bereich seines Gehäusebodens Lösung zugeführt und nach Durchlaufen des Elektrodenpakets mittels überlauf über die Seitenwände des Zellgehäuses einem kaskadenartig angeordneten Ablaufbehälter mit einem eigenen Überlauf zwecks Entgasung zugeführt; nach Passieren eines zweiten Überlaufs wird die nunmehr weitgehend entgaste Lösung wieder in den Lösungsbehälter geleitet und erneut umgewälzt und einer elektrochemischen Behandlung bis zum Erreichen der gewünschten bzw. gesetzlich vorgeschriebenen Restkonzentration weiter zugeführt.In a device for carrying out the methods of Examples 1 to 4, solution is supplied to the cell housing in the region of its housing base by means of a circulating device and, after passing through the electrode pack, is fed to a cascade-like drain container with its own overflow for degassing by means of an overflow over the side walls of the cell housing; After passing through a second overflow, the now largely degassed solution is returned to the solution tank and recirculated and subjected to an electrochemical treatment until the desired or legally prescribed residual concentration is reached.
Claims (15)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19924218916 DE4218916C2 (en) | 1992-06-10 | 1992-06-10 | Use of a grid anode for electrolytic detoxification or regeneration of an aqueous solution containing cyanide |
| DE4218916 | 1992-06-10 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0573743A2 true EP0573743A2 (en) | 1993-12-15 |
| EP0573743A3 EP0573743A3 (en) | 1995-05-17 |
Family
ID=6460670
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP93104209A Withdrawn EP0573743A3 (en) | 1992-06-10 | 1993-03-16 | Process for electrolytic decontaminating or regenerating a cyanide containing aqueous solution and apparatus for performing this process. |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0573743A3 (en) |
| JP (1) | JPH06101081A (en) |
| CA (1) | CA2097869A1 (en) |
| DE (1) | DE4218916C2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116212941A (en) * | 2022-12-08 | 2023-06-06 | 湖南大学 | Preparation method and application of catalyst |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102004023161A1 (en) * | 2004-05-07 | 2005-11-24 | Eilenburger Elektrolyse- Und Umwelttechnik Gmbh | Electrolysis cell with multilayer expanded metal cathodes |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2296597A1 (en) * | 1975-01-03 | 1976-07-30 | Electricity Council | APPARATUS AND METHOD FOR TREATING DILUTED METAL CYANIDE SOLUTIONS |
| JPS53140235A (en) * | 1977-03-02 | 1978-12-07 | Okubo Katsuhiro | Continuous circulation system electrolytic treatment method of silver plating wash water and its device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE758770A (en) * | 1969-11-28 | 1971-04-16 | Loftfield Richard E | Dimensionally stable anode |
| DE2251442C3 (en) * | 1972-10-20 | 1980-01-10 | Gewerkschaft Keramchemie, 5433 Siershahn | Process for the electrolytic detoxification of cyanide |
| DE2836720C2 (en) * | 1978-08-22 | 1986-06-26 | Okubo, Katsuhiro, Tokio/Tokyo | Process for the continuous electrolytic regeneration of a washing solution containing silver cyanide which occurs during electroplating processes and a device for carrying out the process |
-
1992
- 1992-06-10 DE DE19924218916 patent/DE4218916C2/en not_active Expired - Fee Related
-
1993
- 1993-03-16 EP EP93104209A patent/EP0573743A3/en not_active Withdrawn
- 1993-06-07 CA CA 2097869 patent/CA2097869A1/en not_active Abandoned
- 1993-06-10 JP JP5138711A patent/JPH06101081A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2296597A1 (en) * | 1975-01-03 | 1976-07-30 | Electricity Council | APPARATUS AND METHOD FOR TREATING DILUTED METAL CYANIDE SOLUTIONS |
| JPS53140235A (en) * | 1977-03-02 | 1978-12-07 | Okubo Katsuhiro | Continuous circulation system electrolytic treatment method of silver plating wash water and its device |
Non-Patent Citations (1)
| Title |
|---|
| CHEMICAL ABSTRACTS, vol. 90, no. 26, 25. Juni 1979, Columbus, Ohio, US; abstract no. 212309r, UENO 'electrolytic regeneration of washing water from silver electroplating process' Seite 553 ; & JP-A-78 140 235 (OKUBO, KATSUHIRO) 7. Dezember 1978 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116212941A (en) * | 2022-12-08 | 2023-06-06 | 湖南大学 | Preparation method and application of catalyst |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0573743A3 (en) | 1995-05-17 |
| DE4218916A1 (en) | 1993-12-16 |
| CA2097869A1 (en) | 1993-12-11 |
| DE4218916C2 (en) | 1996-03-21 |
| JPH06101081A (en) | 1994-04-12 |
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