EP0115791B1 - Process and apparatus for regenerating a copper-containing etching solution - Google Patents

Process and apparatus for regenerating a copper-containing etching solution Download PDF

Info

Publication number
EP0115791B1
EP0115791B1 EP84100326A EP84100326A EP0115791B1 EP 0115791 B1 EP0115791 B1 EP 0115791B1 EP 84100326 A EP84100326 A EP 84100326A EP 84100326 A EP84100326 A EP 84100326A EP 0115791 B1 EP0115791 B1 EP 0115791B1
Authority
EP
European Patent Office
Prior art keywords
copper
cathode
anode
chloride
face
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
Application number
EP84100326A
Other languages
German (de)
French (fr)
Other versions
EP0115791A1 (en
Inventor
Rudi Dr. Dipl.-Chem. Ott
Heribert Reith
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.)
OFFERTA DI LICENZA AL PUBBLICO
Original Assignee
Robert Bosch GmbH
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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP0115791A1 publication Critical patent/EP0115791A1/en
Application granted granted Critical
Publication of EP0115791B1 publication Critical patent/EP0115791B1/en
Expired legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F1/00—Etching metallic material by chemical means
    • C23F1/46—Regeneration of etching compositions
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C5/00—Electrolytic production, recovery or refining of metal powders or porous metal masses
    • C25C5/02—Electrolytic production, recovery or refining of metal powders or porous metal masses from solutions

Definitions

  • the invention is based on a method for the regeneration of a copper-containing etching solution according to the preamble of claim 1 and on an apparatus for carrying out the method according to claim 3. From DE-A-2 942 504 it is known to etch a copper for the etching of copper. II) -chloride-containing etching solution to use, which contains an alkali chloride, in particular potassium chloride, as complexing agent.
  • a etching solution which is used in particular in the manufacture of printed circuit boards, has the advantage over conventional etching solutions that contain hydrochloric acid as a complexing agent that it has a higher etching speed, that there is no hydrochloric acid mist in the exhaust air and no signs of corrosion on the machines.
  • etching solution can be regenerated by introducing air, which makes the otherwise usual use of hydrogen peroxide superfluous, but this air oxidation requires filtering of the copper (II) hydroxide formed, from which copper is ultimately dissolved by acid and subsequent electrolysis metallic form can be obtained.
  • this process cannot be carried out in a closed circuit, since the copper obtained in the form of copper hydroxide is difficult to filter from the etching solution.
  • DE-A-2 650 912 describes a method for the regeneration of an etchant, in which the same current density prevails at the two electrodes, in which the amount of etchant supplied in the unit of time in the anode is dependent on the respective concentration of the copper I Ions as well as the amount of electricity supplied to the electrodes and at which the redox potential of the etchant to be regenerated is approximately 400 to 460 mV.
  • the etchant to be regenerated is one that uses hydrochloric acid, HCI, as a complexing agent, since there is talk of a hydrochloric acid concentration of about 200 mI / I, which corresponds to about 20% hydrochloric acid, which has a pH of has about - 0.3.
  • the control of the method is carried out both via the amount of the etchant supplied and via the redox potential.
  • the container of the known system is divided by a porous partition into an anode chamber and a cathode chamber, the partition 11 having a diaphragm function.
  • the method according to the invention with the characterizing features of the main claim has the advantage that the composition of the CuCl 2 / KCI etching solution is kept optimally constant with the help of an electrolysis cell, ie in principle only the etched metal is removed from the solution at the same time keeping the Cul / II redox potential constant. There is no chemical consumption, no elemental chlorine is released, the regeneration system can be built very compactly and is therefore very well suited for inclusion in a production line.
  • the device according to the invention for carrying out the above-mentioned method with the characterizing features of claim 3 has the advantage that it can be built in a compact unit and that by attaching a porous partition between the anode and cathode which does not hinder the electrolyte exchange and which does not have a diaphragm. Function that calms the flow generated by the circulation pump at the anode.
  • FIG. 1 shows a perspective view of the regeneration system and FIG. 2 shows a partial section through the disk-shaped cathode.
  • the regeneration system consists of a container 1 made of plastic or insulated metal with an inlet 14 and an outlet 15 to the etching system as well as two connections 7 and 8 for a circulating pump 16.
  • a container 1 made of plastic or insulated metal with an inlet 14 and an outlet 15 to the etching system as well as two connections 7 and 8 for a circulating pump 16.
  • the container 1 there is a circular copper shaft with a serving as cathodic power supply 2 connected copper disc 3, which serves as a cathode.
  • the copper disk 10 has a copper ring 12 on its circumference, the whole is covered with PVC insulation 11 and a titanium ring 13 as the contact material for the etching solution has been shrunk onto the non-insulated end face. Copper cannot serve as a contact material here because it dissolves in the etching medium.
  • the copper shaft 2 is rotatably mounted on the container edge, as indicated in the figure.
  • the disk is driven by a plastic gear, not shown, attached to the copper shaft as electrical insulation, while the current is supplied to the cathode surface via carbon brushes, also not shown, on the rotating copper shaft and from there via the insulated copper disk onto the titanium end face.
  • the anode 4 which consists of titanium, niobium or tantalum and is coated with platinum, iridium or non-stoichiometric platinum metal oxide compounds, is arranged parallel to the end face of the disk 3 and at a short distance from the end face, wherein either solid material or expanded metal can be used .
  • the partition Between the copper disk 3 serving as the cathode and the anode 4 there is a porous intermediate wall 5 made of electrically non-conductive material such as a coarse-pored plastic material made of polypropylene or polyethylene, which serves to keep the strong bath movement caused by the circulation pump 16 away from the cathode 3, without hindering the electrolyte exchange, the partition therefore has no diaphragm function, but only serves as a flow stabilizer.
  • the disc 3 rotates, the copper sludge deposited on the cathode is stripped off and slips into a collecting container (not shown) with the aid of a water spray.
  • the spray rinse water is used in the circuit. After reaching a specified amount of copper sludge and a certain salt concentration in the rinsing water, the contents of the collecting container are pumped on for solid-liquid separation (decanter, filter).
  • the etching solution to be regenerated is fed from the etching system via the inlet 14 to the regeneration system and flows back into the etching system via the outlet 15.
  • metallic copper forms as very fine-crystalline copper sludge by discharging the copper ions at very high current densities.
  • Discharge of the chloride ions forms chlorine at the anode, which dissolves well in water and is quickly distributed throughout the container by the strong bath movement caused by the circulation pump 16.
  • This chlorine oxidizes existing copper (I) chloride to copper (II) chloride.
  • the electrochemical process is controlled by detecting the copper (I) ions with the aid of the redox potential and switching off the current at a limit value which is around 390 mV.
  • the regeneration system as used here has a volume of 210 l, the cathode 3 has a disc diameter of 500 mm with an immersed cathode surface of 2 dm 2, while the anode surface is 25 dm 2 .
  • the circulation pump 16 pumps the entire container volume 25 times an hour.
  • the described etching solution with cathodic current densities between 50 and 150 A / dm 2 and temperatures between 30 and 50 ° C achieved current yields between 0.9 and 1.15 g / Ah copper in powder form.

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einem Verfahren zur Regenerierung einer kupferhaltigen Ätzlösung nach der Gattung des Anspruchs 1 sowie von einer Vorrichtung zur Durchführung des Verfahrens nach Anspruch 3. Aus der DE-A-2 942 504 ist es bekannt, zum Ätzen von Kupfer eine kupfer(II)-chloridhaltige Ätzlösung einzusetzen, die als Komplexbildner ein Alkalichlorid, insbesondere Kaliumchlorid, enthält. Eine solche Ätzlösung, die insbesondere bei der Leiterplattenfertigung eingesetzt wird, hat gegenüber den herkömmlichen Ätzlösungen, die Salzsäure als Komplexbildner enthalten, den Vorteil, dass sie eine höhere Ätzgeschwindigkeit aufweist, dass keinerlei Salzsäurenebel in der Abluft und keine Korrosionserscheinungen an den Maschinen auftreten. Sie lässt sich sowohl in einem Sprühautomaten als auch in einem Tauchprozess, der in einen Galvanisierautomaten integriert ist, einsetzen. Eine solche Ätzlösung lässt sich zwar durch Einleiten von Luft regenerieren, was den sonst üblichen Einsatz von Wasserstoffperoxid überflüssig macht, jedoch erfordert diese Luftoxidation ein Filtrieren des dabei gebildeten Kupfer(II)-Hydroxids, aus dem schliesslich durch Lösen in Säure und anschliessende Elektrolyse Kupfer in metallischer Form gewonnen werden kann. Dieses Verfahren lässt sich indessen nicht in einem geschlossenen Kreislauf verwirklichen, da das in Form von Kupferhydroxid anfallende Kupfer aus der Ätzlösung schlecht filtrierbar ist.The invention is based on a method for the regeneration of a copper-containing etching solution according to the preamble of claim 1 and on an apparatus for carrying out the method according to claim 3. From DE-A-2 942 504 it is known to etch a copper for the etching of copper. II) -chloride-containing etching solution to use, which contains an alkali chloride, in particular potassium chloride, as complexing agent. Such an etching solution, which is used in particular in the manufacture of printed circuit boards, has the advantage over conventional etching solutions that contain hydrochloric acid as a complexing agent that it has a higher etching speed, that there is no hydrochloric acid mist in the exhaust air and no signs of corrosion on the machines. It can be used both in a spraying machine and in a dipping process that is integrated in an electroplating machine. Such an etching solution can be regenerated by introducing air, which makes the otherwise usual use of hydrogen peroxide superfluous, but this air oxidation requires filtering of the copper (II) hydroxide formed, from which copper is ultimately dissolved by acid and subsequent electrolysis metallic form can be obtained. However, this process cannot be carried out in a closed circuit, since the copper obtained in the form of copper hydroxide is difficult to filter from the etching solution.

Die DE-A-2 650 912 beschreibt ein Verfahren zur Regeneration eines Ätzmittels, bei welchem an den beiden Elektroden die gleiche Stromdichte herrscht, bei welchem die in der Zeiteinheit der Anode zugeführte Menge des Ätzmittels abhängig ist von der jeweiligen Konzentration der Kupfer-I-Ionen sowie auch der den Elektroden zugeführten Elektrizitätsmenge und bei dem das Redoxpotential des zu regenerierenden Ätzmittels etwa 400 bis 460 mV beträgt. Bei dem zu regenerierenden Ätzmittel handelt es sich um ein solches, das als Komplexbildner Salzsäure, HCI, einsetzt, da von einer Salzsäurekonzentration von etwa 200 mI/I die Rede ist, was einer etwa 20%igen Salzsäure entspricht, die einen pH-Wert von etwa - 0,3 aufweist.DE-A-2 650 912 describes a method for the regeneration of an etchant, in which the same current density prevails at the two electrodes, in which the amount of etchant supplied in the unit of time in the anode is dependent on the respective concentration of the copper I Ions as well as the amount of electricity supplied to the electrodes and at which the redox potential of the etchant to be regenerated is approximately 400 to 460 mV. The etchant to be regenerated is one that uses hydrochloric acid, HCI, as a complexing agent, since there is talk of a hydrochloric acid concentration of about 200 mI / I, which corresponds to about 20% hydrochloric acid, which has a pH of has about - 0.3.

Die Steuerung des Verfahrens wird sowohl über die Menge des zugeführten Ätzmittels als auch über das Redoxpotential durchgeführt. Der Behälter der bekannten Anlage ist durch eine poröse Trennwand in eine Anodenkammer und eine Kathodenkammer unterteilt, wobei die Trennwand 11 eine Diaphragma-Funktion auszuüben hat.The control of the method is carried out both via the amount of the etchant supplied and via the redox potential. The container of the known system is divided by a porous partition into an anode chamber and a cathode chamber, the partition 11 having a diaphragm function.

Aus den Druckschriften DD-A-45299, DE-B-1 223653 und US-A-3 825 484 sind Vorrichtungen zur Regenerierung von Ätzlösungen bekannt, die als Kathoden kreisrunde, rotierende Scheiben aufweisen. Diese stellen aber lediglich einen Teilaspekt der hier zu beschreibenden Vorrichtung dar. Vorteile der ErfindungFrom the documents DD-A-45299, DE-B-1 223653 and US-A-3 825 484 devices for the regeneration of etching solutions are known which have circular, rotating disks as cathodes. However, these represent only a partial aspect of the device to be described here. Advantages of the invention

Das erfindungsgemässe Verfahren mit den kennzeichnenden Merkmalen des Hauptanspruchs hat demgegenüber den Vorteil, dass die CuCl2/KCI-Ätzlösung mit Hilfe einer Elektrolysezelle in ihrer Zusammensetzung in optimaler Weise konstant gehalten wird, d.h. es wird im Prinzip nur das abgeätzte Metall aus der Lösung entfernt bei gleichzeitiger Konstanthaltung des Cul/II-Redoxpotentials. Es tritt kein Chemikalienverbrauch auf, es wird kein elementares Chlor freigesetzt, die Regenerieranlage lässt sich sehr kompakt bauen und ist daher sehr gut für die Einbeziehung in eine Fertigungsstrasse geeignet.The method according to the invention with the characterizing features of the main claim has the advantage that the composition of the CuCl 2 / KCI etching solution is kept optimally constant with the help of an electrolysis cell, ie in principle only the etched metal is removed from the solution at the same time keeping the Cul / II redox potential constant. There is no chemical consumption, no elemental chlorine is released, the regeneration system can be built very compactly and is therefore very well suited for inclusion in a production line.

Durch die in den Unteransprüchen aufgeführten Massnahmen sind vorteilhafte Weiterbildungen und Verbesserungen des im Hauptanspruch angegebenen Verfahrens möglich. Besonders vorteilhaft ist es, im Falle des Ätzens von Legierungen, die neben Kupfer unedlere Metalle wie z.B. Zink enthalten, wenn man die Regenerieranlage mit einer kathodischen Stromdichte zwischen 100 und 400 A/dm2 und bei einem pH-Wert über 1,0 betreibt, da in diesem Falle nicht nur das Kupfer in Pulverform, sondern gleichzeitig auch das Zink in Pulverform abgeschieden wird.Advantageous further developments and improvements of the method specified in the main claim are possible through the measures listed in the subclaims. It is particularly advantageous, in the case of the etching of alloys which, in addition to copper, contain base metals such as zinc, if the regeneration system is operated with a cathodic current density between 100 and 400 A / dm 2 and at a pH value above 1.0. since in this case not only the copper in powder form, but also the zinc in powder form is deposited at the same time.

Die erfindungsgemässe Vorrichtung zur Durchführung des obengenannten Verfahrens mit den kennzeichnenden Merkmalen des Anspruchs 3 hat den Vorteil, dass sie sich in einer kompakten Einheit bauen lässt und dass durch die Anbringung einer den Elektrolytaustausch nicht behindernden, porösen Trennwand zwischen Anode und Kathode, die keine Diaphragma-Funktion hat, die durch die Umwälzpumpe erzeugte Strömung an der Anode beruhigt.The device according to the invention for carrying out the above-mentioned method with the characterizing features of claim 3 has the advantage that it can be built in a compact unit and that by attaching a porous partition between the anode and cathode which does not hinder the electrolyte exchange and which does not have a diaphragm. Function that calms the flow generated by the circulation pump at the anode.

Zeichnungdrawing

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Es zeigen Figur 1 eine perspektivische Darstellung der Regenerieranlage und Figur 2 einen Teilschnitt durch die scheibenförmige Kathode.An embodiment of the invention is shown in the drawing and explained in more detail in the following description. 1 shows a perspective view of the regeneration system and FIG. 2 shows a partial section through the disk-shaped cathode.

Beschreibung des AusführungsbeispielsDescription of the embodiment

Die Regenerieranlage besteht aus einem Behälter 1 aus Kunststoff oder isoliertem Metall mit einem Zulauf 14 und einem Ablauf 15 an die Ätzanlage sowie zwei Anschlüssen 7 und 8 für eine Umwälzpumpe 16. In dem Behälter 1 läuft eine kreisrunde, fest mit einer als kathodische Stromzuführung dienende Kupferwelle 2 verbundene Kupferscheibe 3, die als Kathode dient. Gemäss Figur 2 trägt die Kupferscheibe 10 an ihrem Umfang einen Kupferring 12, das Ganze ist mit einer Isolierung 11 aus PVC überzogen und auf die nicht isolierte Stirnfläche ein Titanreif 13 als Kontaktwerkstoff zur Ätzlösung aufgeschrumpft worden. Kupfer kann hier nicht als Kontaktwerkstoff dienen, da dieses sich in dem Ätzmedium auflöst. Die Kupferwelle 2 ist auf dem Behälterrand, wie in der Figur angedeutet, drehbar gelagert. Der Antrieb der Scheibe erfolgt über ein auf der Kupferwelle befestigtes, nicht dargestelltes Kunststoffzahnrad als elektrische Isolierung, während die Stromzuführung zur Kathodenoberfläche über ebenfalls nicht dargestellte Kohlebürsten auf die sich drehende Kupferwelle und von da über die isolierte Kupferscheibe auf die Stirnfläche aus Titan erfolgt. In dem Behälter 1 ist parallel zur Stirnfläche der Scheibe 3 und mit geringem Abstand zur Stirnfläche die Anode 4 angeordnet, die aus Titan, Niob oder Tantal besteht, das mit Platin, Iridium oder nichtstöchiometrischen Platinmetalloxidverbindungen beschichtet ist, wobei entweder Vollmaterial oder Streckmetall eingesetzt werden kann. - Zwischen der als Kathode dienenden Kupferscheibe 3 und der Anode 4 befindet sich eine poröse Zwischenwand 5 aus elektrisch nicht leitendem Material wie einem grobporigen Kunststoffmaterial aus Polypropylen oder Polyäthylen, die dazu dient, die durch die Umwälzpumpe 16 verursachte starke Badbewegung von der Kathode 3 fernzuhalten, ohne den Elektrolytaustausch zu behindern, die Zwischenwand hat also keine Diaphragma-Funktion, sondern dient lediglich als Strömungsberuhiger. - Am Behälterrand befestigt, mit losem Kontakt zur Stirnfläche der Kathode 3 befindet sich eine Abstreifvorrichtung 6. Bei der drehenden Bewegung der Scheibe 3 wird so der an der Kathode abgeschiedene Kupferschlamm abgestreift und rutscht mit Hilfe einer Wasserspritzspülung in einen nicht dargestellten Auffangbehälter. Das Spritzspülwasser wird im Kreislauf eingesetzt. Nach Erreichen einer vorgegebenen Kupferschlamm-Menge und einer bestimmten Salzkonzentration im Spülwasser wird der Inhalt des Auffangbehälters zur Fest-Flüssigabtrennung (Dekanter, Filter) weitergepumpt.The regeneration system consists of a container 1 made of plastic or insulated metal with an inlet 14 and an outlet 15 to the etching system as well as two connections 7 and 8 for a circulating pump 16. In the container 1 there is a circular copper shaft with a serving as cathodic power supply 2 connected copper disc 3, which serves as a cathode. According to FIG. 2, the copper disk 10 has a copper ring 12 on its circumference, the whole is covered with PVC insulation 11 and a titanium ring 13 as the contact material for the etching solution has been shrunk onto the non-insulated end face. Copper cannot serve as a contact material here because it dissolves in the etching medium. The copper shaft 2 is rotatably mounted on the container edge, as indicated in the figure. The disk is driven by a plastic gear, not shown, attached to the copper shaft as electrical insulation, while the current is supplied to the cathode surface via carbon brushes, also not shown, on the rotating copper shaft and from there via the insulated copper disk onto the titanium end face. In the container 1, the anode 4, which consists of titanium, niobium or tantalum and is coated with platinum, iridium or non-stoichiometric platinum metal oxide compounds, is arranged parallel to the end face of the disk 3 and at a short distance from the end face, wherein either solid material or expanded metal can be used . - Between the copper disk 3 serving as the cathode and the anode 4 there is a porous intermediate wall 5 made of electrically non-conductive material such as a coarse-pored plastic material made of polypropylene or polyethylene, which serves to keep the strong bath movement caused by the circulation pump 16 away from the cathode 3, without hindering the electrolyte exchange, the partition therefore has no diaphragm function, but only serves as a flow stabilizer. - Attached to the edge of the container, with loose contact to the end face of the cathode 3, there is a stripping device 6. When the disc 3 rotates, the copper sludge deposited on the cathode is stripped off and slips into a collecting container (not shown) with the aid of a water spray. The spray rinse water is used in the circuit. After reaching a specified amount of copper sludge and a certain salt concentration in the rinsing water, the contents of the collecting container are pumped on for solid-liquid separation (decanter, filter).

Die zu regenerierende Ätzlösung wird aus der Ätzanlage über den Zulauf 14 der Regenerieraniage zugeführt und fliesst über den Ablauf 15 der Ätzanlage wieder zu. In der Regenerieranlage bildet sich bei Stromdurchgang an der Kathode 3 durch Entladung der Kupferionen bei sehr hohen Stromdichten metallisches Kupfer als sehr feinkristalliner Kupferschlamm. An der Anode bildet sich durch Entladung der Chloridionen Chlor, das sich in Wasser gut löst und durch die von der Umwälzpumpe 16 verursachte starke Badbewegung schnell im ganzen Behälter verteilt wird. Dieses Chlor oxidiert vorhandenes Kupfer(I)-Chlorid zu Kupfer(II)-Chlorid. Um zu verhindern, dass mehr Chlor gebildet als für die Oxidation benötigt wird, erfolgt eine Steuerung des elektrochemischen Vorgangs durch Erfassen der Kupfer(I)-lonen mit Hilfe des Redoxpotentials und Abschaltung des Stroms bei einem Grenzwert, der bei etwa 390 mV liegt.The etching solution to be regenerated is fed from the etching system via the inlet 14 to the regeneration system and flows back into the etching system via the outlet 15. When the current passes through the cathode 3 in the regeneration system, metallic copper forms as very fine-crystalline copper sludge by discharging the copper ions at very high current densities. Discharge of the chloride ions forms chlorine at the anode, which dissolves well in water and is quickly distributed throughout the container by the strong bath movement caused by the circulation pump 16. This chlorine oxidizes existing copper (I) chloride to copper (II) chloride. To prevent more chlorine from being formed than is required for the oxidation, the electrochemical process is controlled by detecting the copper (I) ions with the aid of the redox potential and switching off the current at a limit value which is around 390 mV.

Es folgen jetzt Beispiele zur Regenerierung einer Ätzlösung, die beim Sprühätzen mit den folgenden Parametern eingesetzt wird:

  • Cu: 50 g/I
  • KCI: 150 g/I
  • Redoxpotential: 390 mV
  • Temperatur: 45 °C
  • Druck: 2 bar
  • Ätzgeschwindigkeit: 38 pm/min
  • pH-Wert: 2,3
The following are examples of the regeneration of an etching solution used in spray etching with the following parameters:
  • Cu: 50 g / l
  • KCI: 150 g / l
  • Redox potential: 390 mV
  • Temperature: 45 ° C
  • Pressure: 2 bar
  • Etching speed: 38 pm / min
  • pH: 2.3

Die Regenerieranlage, wie sie hier benutzt wurde, besitzt ein Volumen von 210 I, die Kathode 3 einen Scheibendurchmesser von 500 mm mit einer eingetauchten Kathodenoberfläche von 2 dm2 während die Anodenoberfläche 25 dm2 beträgt. Die Umwälzpumpe 16 pumpt das gesamte Behältervolumen 25mal in der Stunde um. In der Regenerieranlage wurden mit der beschriebenen Ätzlösung bei kathodischen Stromdichten zwischen 50 und 150 A/dm2 und Temperaturen zwischen 30 und 50°C Stromausbeuten zwischen 0,9 und 1,15 g/Ah Kupfer in Pulverform erzielt.The regeneration system as used here has a volume of 210 l, the cathode 3 has a disc diameter of 500 mm with an immersed cathode surface of 2 dm 2, while the anode surface is 25 dm 2 . The circulation pump 16 pumps the entire container volume 25 times an hour. In the regeneration system, the described etching solution with cathodic current densities between 50 and 150 A / dm 2 and temperatures between 30 and 50 ° C achieved current yields between 0.9 and 1.15 g / Ah copper in powder form.

Im folgenden Beispiel wurde eine Ätzlösung regeneriert, die abgeätztes Zink neben Kupfer enthält:

  • Cu: 50 g/I
  • KCI: 100 g/1
  • Zn: 20 g/I
  • Temperatur: 22 °C
  • pH-Wert: 1,5.
In the following example, an etching solution was regenerated that contains etched zinc in addition to copper:
  • Cu: 50 g / l
  • KCI: 100 g / 1
  • Zn: 20 g / l
  • Temperature: 22 ° C
  • pH: 1.5.

Bei einer kathodischen Stromdichte von 300 A/dm2 wurde ein Metallpulver erhalten, das zu 58% aus Kupfer und zu 42% aus Zink besteht.At a cathodic current density of 300 A / dm 2 , a metal powder was obtained which consists of 58% copper and 42% zinc.

Claims (6)

1. Process for regenerating a cupriferous etching solution which contains copper (II) chloride and alkali chloride as the complexing agent and is passed through a regeneration unit which has a cathode (3) and an anode (4) to which a direct voltage is applied with the result that metallic copper is deposited at the cathode (3) as fine crystalline sludge while at the anode (4) chlorine is formed which oxidizes copper (I) chloride to copper (11) chloride, characterized in that a current density of 40 to 400 A/dm2 prevails at the cathode (3) and a current density of 1 to 100 A/dm2 prevails at the anode (4), in that the current is switched off at a limiting value of 390 mV of the redox potential to prevent formation of excess chlorine at the anode (4) and in that the pH value of the etching solution lies between 1 and 3, means being provided which ensure highly turbulent liquid agitation at the anode (4) but only weak liquid agitation at the cathode (3).
2. Process according to Claim 1, characterized in that, when etching brass or tombac, the cathodic current density lies between 100 and 400 A/dm2 to give simultaneous deposition of copper and zinc.
3. Device for carrying out the process according to Claim 1 or 2, with a container (1) made of an electrically insulating material, on the upper edge of which is mounted a circular, disc-shaped cathode (3) carried on an axle (2) serving as a current conductor, an anode (4) installed in the container (1) parallel to the face of the cathode (3), a stripping device (6), fixed at the upper edge of the container, which is in loose contact with the face of the cathode (3), and connections (7) and (8) for a circulation pump (16), characterized by a porous partition (5) installed between anode (4) and cathode (3) which does not impede the exchange of electrolyte and which has no diaphragm function and only ensures that the flow, which is generated by the circulation pump (16) during the use of the device, is calmed at the cathode (3).
4. Device according to Claim 3, characterized in that the cathode (3) consists of a copper disc (10) which has an insulation (11), in that a copper ring (12) is let into the face of the insulation (11) in contact with the copper disc (10) and in that the face of the cathode (3) consisting of the copper ring (12) and the insulation (11) carries a ring (13) made of titanium, niobium or tantalum which acts as the contact material (Fig. 2).
5. Device according to Claim 3, characterized in that the anode (4) consists of titanium, niobium or tantalum in the shape of a sheet, bar or of expanded metal and carries a surface coating made of platinum, iridium or non-stoichiometric platinum metal oxide compounds.
6. Device according to Claim 3, characterized in that the porous partition (5) consists of a coarse- pored woven material or perforated solid material made of polypropylene or polyethylene.
EP84100326A 1983-02-03 1984-01-13 Process and apparatus for regenerating a copper-containing etching solution Expired EP0115791B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19833303594 DE3303594A1 (en) 1983-02-03 1983-02-03 METHOD AND DEVICE FOR REGENERATING A copper-containing etching solution
DE3303594 1983-02-03

Publications (2)

Publication Number Publication Date
EP0115791A1 EP0115791A1 (en) 1984-08-15
EP0115791B1 true EP0115791B1 (en) 1988-06-01

Family

ID=6189908

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84100326A Expired EP0115791B1 (en) 1983-02-03 1984-01-13 Process and apparatus for regenerating a copper-containing etching solution

Country Status (4)

Country Link
US (1) US4508599A (en)
EP (1) EP0115791B1 (en)
JP (1) JPS59143072A (en)
DE (2) DE3303594A1 (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1987000210A1 (en) * 1985-06-27 1987-01-15 Cheminor A/S A method for the production of metals by electrolysis
DE3832674A1 (en) * 1988-09-27 1990-03-29 Kodak Ag METAL RECOVERY DEVICE
DE4010034A1 (en) * 1990-03-29 1991-10-02 Hoellmueller Maschbau H DEVICE FOR ELECTROLYTIC REGENERATION OF A METAL CONTAINER, ESPECIALLY COPPER CONTAINER
SG46415A1 (en) * 1991-10-28 1998-02-20 Nittetsu Mining Co Ltd Method for treating etchant
GB2293390A (en) * 1994-09-20 1996-03-27 British Tech Group Simultaneous etchant regeneration and metal deposition by electrodialysis
JP2941741B2 (en) * 1997-06-03 1999-08-30 核燃料サイクル開発機構 Dry reprocessing method and spent reprocessing device for spent nuclear fuel
CN110306209A (en) * 2019-08-09 2019-10-08 郑州金泉矿冶设备有限公司 The equipment of electrolysis method production super fine silver powder

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD45299A (en) *
US1959376A (en) * 1930-09-26 1934-05-22 Nichols Copper Co Process for producing metal powders
FR1213119A (en) * 1957-10-28 1960-03-29 Western Electric Co Bath to corrode copper and regeneration of this bath
DE1223653B (en) * 1960-01-11 1966-08-25 Siemens Ag Device for the continuous electro-lytic regeneration of copper chloride etching solutions
US3825484A (en) * 1971-04-29 1974-07-23 N Fronsman Electrolytic regenerator for chemical etchants including scraper means and rotating cathodes
BE789944A (en) * 1971-10-12 1973-02-01 Shipley Co REGENERATION OF A USED COPPER ATTACK SOLUTION
JPS5124537A (en) * 1974-08-26 1976-02-27 Hitachi Ltd Etsuchinguyokuno saiseihoho
SU548051A1 (en) * 1975-03-17 1977-10-05 Горьковский политехнический институт им.А.А.Жданова Method of regeneration of ferrumcopper-chloride etching solutions
DE2641905C2 (en) * 1976-09-17 1986-03-20 Geb. Bakulina Galina Aleksandrovna Batova Process for the regeneration of used etching solutions
DE2650912A1 (en) * 1976-11-06 1978-05-18 Hoellmueller Maschbau H Electrolytic regeneration of copper etching reagent - contg. chloride and cuprous ion, with control of copper concn. in reagent and current density
DE2850564C2 (en) * 1978-11-22 1982-12-23 Kernforschungsanlage Jülich GmbH, 5170 Jülich Method and device for regenerating an etching solution containing copper (II) chloride and / or iron (III) chloride in an electrolytic cell
JPS5629686A (en) * 1979-08-17 1981-03-25 Kazuo Ogawa Electrolytic cathode plate for copper recovery
JPS5914097B2 (en) * 1980-07-30 1984-04-03 新日本製鐵株式会社 Ferritic heat-resistant steel with improved toughness

Also Published As

Publication number Publication date
DE3471692D1 (en) 1988-07-07
JPH0472910B2 (en) 1992-11-19
JPS59143072A (en) 1984-08-16
DE3303594A1 (en) 1984-08-09
US4508599A (en) 1985-04-02
EP0115791A1 (en) 1984-08-15

Similar Documents

Publication Publication Date Title
US4028199A (en) Method of producing metal powder
EP0268738A2 (en) Electrolytic cell for separating metals
EP0158910B1 (en) Process for recovering copper from an ammoniacal copper-etching solution, and regeneration of this solution
DE2523950A1 (en) ELECTROCHEMICAL DEVICE AND ITS USE
DE4002700A1 (en) ELECTROCHEMICALLY MACHINABLE WORKPIECE AND METHOD FOR ELECTROCHEMICALLY WORKING A METAL WORKPIECE
DE10025551C2 (en) Cathode for the electrochemical regeneration of permanganate etching solutions, process for their preparation and electrochemical regeneration device
DE10013339C1 (en) Process for regulating the concentration of metal ions in an electrolyte liquid comprises feeding part of the liquid through an auxiliary cell consisting of an insoluble auxiliary anode and an auxiliary cathode
EP0638664A1 (en) Process and apparatus for regenerating solutions containing metal ions and sulfuric acid
DE2850542C2 (en) Process for etching surfaces made of copper or copper alloys
DE602004009572T2 (en) METHOD FOR REGENERATING IRON-BASED SOLID SOLUTIONS FOR USE IN THE PAINTING OR REFURBISHING OF COPPER OR COPPER ALLOYS AND DEVICE FOR CARRYING OUT THE METHOD
EP0115791B1 (en) Process and apparatus for regenerating a copper-containing etching solution
EP1379712A2 (en) Method and device for recovering metals with pulsating cathode currents also combined with anode coupling processes
DE2607512C2 (en) Process for the production of a metal powder, electrolysis cell for carrying out the process and application of the process
DE3029364A1 (en) PROCESS FOR THE MANUFACTURE OF LOW HYDROGEN OVERVOLTAGE CATHODE AND THEIR USE
WO1999010564A2 (en) Method and device for regulating the concentration of substances in electrolytes
WO2000026440A2 (en) Circular method for pickling copper and copper alloys
WO2010078866A2 (en) Method and device for regenerating peroxodisulfate pickling solution
DE2522926A1 (en) PROCESS FOR MANUFACTURING METAL-CLAD LONG STRETCH ALUMINUM MATERIALS
DE2025211A1 (en) Selective anodic recovery of silver - from scrap by electro - -deposition from aq soln
DE19653273C2 (en) A method for recovering at least one metal deposited on a substrate
WO1998048081A2 (en) Method for electroplating metallic and non-metallic endless products and device for carrying out said method
WO1986001542A1 (en) Process, device and means for the production of ozone
DE1808471C3 (en) Process for the recovery of gold from galvanic washing water
DE1273498B (en) Process for the manufacture of electrodes for electrochemical purposes
DE1671468A1 (en) Method for treating electrodes

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19840113

AK Designated contracting states

Designated state(s): DE FR GB IT

17Q First examination report despatched

Effective date: 19860403

D17Q First examination report despatched (deleted)
GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
REF Corresponds to:

Ref document number: 3471692

Country of ref document: DE

Date of ref document: 19880707

ET Fr: translation filed
ITF It: translation for a ep patent filed

Owner name: STUDIO JAUMANN

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: 746

ITPR It: changes in ownership of a european patent

Owner name: OFFERTA DI LICENZA AL PUBBLICO

REG Reference to a national code

Ref country code: FR

Ref legal event code: DL

ITTA It: last paid annual fee
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19940105

Year of fee payment: 11

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19950113

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19950323

Year of fee payment: 12

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19950113

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19950929

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19961001

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19970121

Year of fee payment: 14