EP0487881B1 - Verfahren und Vorrichtung zum elektrolytischen Austragen von Metallen aus einer Metallionen enthaltenden Lösung sowie Elektrode zur Durchführung des Verfahrens - Google Patents

Verfahren und Vorrichtung zum elektrolytischen Austragen von Metallen aus einer Metallionen enthaltenden Lösung sowie Elektrode zur Durchführung des Verfahrens Download PDF

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Publication number
EP0487881B1
EP0487881B1 EP91117551A EP91117551A EP0487881B1 EP 0487881 B1 EP0487881 B1 EP 0487881B1 EP 91117551 A EP91117551 A EP 91117551A EP 91117551 A EP91117551 A EP 91117551A EP 0487881 B1 EP0487881 B1 EP 0487881B1
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EP
European Patent Office
Prior art keywords
electrode
cell
metal
electrolyte
endless band
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
Application number
EP91117551A
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German (de)
English (en)
French (fr)
Other versions
EP0487881A1 (de
Inventor
Jochen-Werner Kühn-von Burgsdorff
Ulrich Dr. Ströder
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.)
WC Heraus GmbH and Co KG
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WC Heraus GmbH and Co KG
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Publication of EP0487881A1 publication Critical patent/EP0487881A1/de
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
    • C25C7/06—Operating or servicing
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
    • C25C7/02—Electrodes; Connections thereof

Definitions

  • the invention relates to a method for the electrolytic removal of metal from a solution containing metal ions, an anode connected to the positive pole of a voltage source being immersed in the solution in a first cell and metal being deposited from the solution on one electrode, this electrode in a second a cell containing liquid electrolyte is transferred and the deposited metal is again released from the electrode into the electrolyte and deposited again from the electrolyte on a counterelectrode, and the metal-free electrode is then transferred from the second cell back into the first cell, and a device and an electrode for performing the method.
  • DE-A-22 32 903 discloses a process for the electrolytic refining of copper from its salt solutions contaminated with other metal ions using titanium electrodes as electrolyte sheets; the titanium electrodes are used as cathodes in a first solution and, after the copper has been deposited, are fed to a second bath with pure electrolyte, where the previously deposited copper is 100% detached again, the titanium electrode being connected anodically. Titanium is used as the material for the switchable electrode.
  • the electrode can be used again without intermediate treatment in the first bath, in which it is connected cathodically; the titanium electrode behaves like a copper anode with anodic switching, as long as copper adheres to the titanium anode; the after the dissolution of the Passivation of titanium that occurs in copper then becomes noticeable through a sharp drop in current or rise in voltage. Even if this spontaneous drop in current and voltage increase can be used well for automatic monitoring of the electrolysis process, the possibility of largely automated operation is largely restricted, since the switch-off process of the cathodically switched titanium electrode is not so easy to monitor; Automatic operation is problematic in that special handling tools are required to convert the titanium plate into the respective solution.
  • GB-A-13 45 411 Another process for the electrorefining of a metal from the group of copper, zinc, nickel, lead or manganese using a titanium electrode as the cathode is known from GB-A-13 45 411.
  • the removed metal is removed from the titanium electrode by mechanical stripping.
  • the electrical series connection of several copper refining cells is described, all of which are traversed by the same current; different cathode current densities can be achieved depending on the size of the cathode surfaces immersed in the electrolyte.
  • EP-A-0 049 172 discloses a process for obtaining a noble metal on its solution by adsorbing a dissolved compound of the noble metal on activated carbon, the activated carbon being in the form of a body comprising fibers of activated carbon; the fiber-containing body can be used as an electrically conductive circulating endless belt in an electrochemical process for the depletion of metal in solutions and for the regeneration of electrolyte belts; the endless belt working in continuous operation is connected as an anode in an electrochemical cell.
  • WO-A-90/03456 discloses a device for the electrolytic regeneration of metal, in particular silver, from the photographic development process, the metal being deposited on the cathodically connected endless belt and mechanically stripped off the belt outside the solution.
  • the invention has for its object to provide an automatic process for the electrolytic refining of metals from a solution containing metal ions, the transport of the electrode provided with the deposited metal takes place automatically in a further solution and a respective attitude to Optimization of the process parameters is possible. Furthermore, a device and an electrode for carrying out the method are to be created, wherein in particular an optimal use of energy is also to be achieved.
  • an electrically conductive first endless belt is used as the electrode, which is circulated between the first and the second cell, partly immersed in the solution and the electrolyte, and in that the belt in the first cell is operated cathodically and anodically in the second cell, a counter electrode being connected as the cathode to the negative pole of the voltage source.
  • the object is achieved in that the electrode is an electrically conductive first endless band, which is partially immersed in the solution and the electrolyte, the first endless band being connected cathodically in the first cell and anodically in the second cell and a counter electrode is designed as a cathode, which is connected to the negative pole of the voltage source and that the device has a guide device with deflection and / or drive rollers for guiding the first endless belt, the drive roller and some deflection rollers outside the solution and the Electrolytes are arranged.
  • the object is achieved in that it consists of a flexible endless belt, at least whose outwardly facing surface is electrically conductive and that it has at least two deflection and / or drive rollers which are arranged one above the other, at a distance from one another are, wherein at least an upper roller abuts the inner surface of the endless belt and a lower roller abuts the electrically conductive surface of the belt.
  • the endless belt preferably consists of a film made of electrically conductive material; however, it is also possible to use an endless belt in the form of a network or a chain.
  • Metal from the platinum metal group or valve metal or a valve metal base alloy is preferably used as the material for the band; However, it is also possible to use electrically conductive plastic or plastic with electrically conductive fillers in contact with one another as the material for the band.
  • the endless band thus forms a bipolar flexible electrode.
  • a major advantage of the invention is that the endless belt effects both the electrical connection between the individual cells and the mass transfer of the deposited metal into the next cell.
  • the trough 1 consists of two trough regions 2, 3 which are separated from one another by an intermediate wall 4.
  • the level 5 of the solution 5 located in the trough regions 2, 3 and the electrolyte 6 are numbered by the level symbols 5 ', 6'.
  • solution 5 of the trough area 2 there is an anode 7 which is connected to the positive pole 8 of a voltage source 9.
  • a partial section 10 ′ of a flexible belt 10 guided over drive or deflection rollers 11, 12, 13, 14, 15, 16, 17, 18 is immersed in the solution 5, the deflection rollers being arranged in predetermined positions relative to the trough.
  • the band 10 consists of a metal foil with a thickness in the range of 50 to 100 ⁇ m, preferably of a titanium foil.
  • a net made of a platinum group metal or a band made of electrically conductive plastic or a band made of interlinked electrically conductive plastic bodies as the endless band.
  • the use of a platinum mesh has proven to be particularly useful.
  • the U-shaped bent ends of the sections 10 'and 10' 'of the flexible band are each guided over the deflection rollers 17, 18 arranged in the bottom area of the trough areas 2, 3; all axes of the deflection rollers 11 to 18 run horizontally.
  • section 10 'of the flexible strip 10 functions as a cathode and section 10' 'as an anode; there is also a cathode 19 in the electrolyte 6 of the trough region 3, which is connected to the negative terminal 20 of the voltage source 9.
  • a contaminated copper extraction solution containing 200 g / l sulfuric acid and 45 g / l copper is used in trough area 2, the anode 7 being an insoluble electrode which produces oxygen.
  • trough area 3 there is an aqueous electrolyte containing 200 g / l sulfuric acid with 45 g / l copper.
  • a steel sheet serves as cathode 19.
  • the flexible strip is put into circulation at a strip circulation speed of approx. 0.2 m / min at a current density of 150 A / m at 60 ° C., the portion 10 ′ acting as cathode of the strip continuously passed through solution 5 copper.
  • both trough regions 2, 3 acting as electrolysis cells form a single electrolyzer with cells connected in series, the amount of copper deposited on the steel sheet corresponds exactly to the same amount that was previously deposited on the section 10 ′ of the flexible strip 10 in the trough region 2 would have.
  • a continuous belt transport is preferably carried out.
  • the analyzes of the copper deposited on section 10 'of the endless belt 10 and the cathode 19 are listed in the table below: Metal deposited on section 10 ' Metal deposited on cathode 19 CU 99.5% 99.99% Pb 800 ppm ⁇ 5 ppm Zn 15 ppm ⁇ 5 ppm Ni 600 ppm ⁇ 5 ppm Fe 300 ppm ⁇ 5 ppm Ag 450 ppm ⁇ 5 ppm
  • Figure 2 shows a modification of the device shown in Figure 1, wherein anode 7 from an electrically conductive, electrolyte-resistant anode basket basket 7 ', which contains the starting material 7 "in granular form.
  • the starting material is deposited on the part 10' of the flexible belt which acts as a cathode and, after a transport movement of the flexible belt 10, is transferred into the trough region 3, where that previously deposited material is dissolved and deposited on cathode 19.
  • the solution in the trough areas 2 and 3 consists of HNO3 (nitric acid with a pH of 3), which contains 50g / 1 silver, 5g / l NaNO3 (sodium nitrate).
  • FIG. 3 Another embodiment is shown in FIG. 3, the trough 21 being divided into three trough regions 22, 23, 24. Partition walls 4 are arranged between the trough regions.
  • the basic mode of operation of the first cell 22 formed in trough 21 with solution 25 corresponds to the embodiment explained with reference to FIGS. 1 and 2.
  • partial section 10 ′′ serves as an anode in the electrolyte 26 present there, the previously deposited metal content being dissolved in the electrolyte 26 and being deposited on the partial area 30 ′ of a further flexible strip 30 acting as a cathode.
  • the flexible strip 30 corresponds in structure and mode of operation to that already Band 10 described with reference to FIGS.
  • the flexible band 30 thus acts in the trough area 23 with its section 30 'as a cathode, while in the adjacent trough area 24 with its partial section 30''acts as an anode, the previously deposited metal being dissolved again and on the cathode 19 is deposited.
  • the solution 25 and the electrolytes 26 and 27 likewise consist of an electrolyte made of sulfuric acid and copper dissolved therein, as described with reference to FIG.
  • a copper sheet according to FIG. 1 or an anode basket for raw granules according to FIG. 2 again serves as the anode.
  • the belt transport of the flexible belts 10 and 30 can take place continuously or in cycles; it is possible to provide a coupling between the drives of the belt transports for the flexible belts 10 and 30.
  • Such an arrangement is particularly suitable for combining extraction electrolysis in the trough region 22 and refining electrolysis in the trough regions 23 and 24.
  • the device known from FIG. 3 is provided in its third cell 27 instead of a plate-shaped counterelectrode with a circumferential, electrically conductive endless band 31 as the cathode; the endless belt 31 is connected via a current collector 32 and line 33 to the negative pole 20 of the DC voltage source 9; the section 30 ′′ dipping into the trough area 24 acts as an anode, as already explained with reference to FIG. 3, the metal previously deposited in the trough area 23 on the section 30 ′ now being brought into solution in the electrolyte 27; after deposition of the metal on the cathodically connected endless belt 31, the belt runs through mechanical separator 34 for removing the deposited metal from the belt.
  • the endless belt 31 passes in the separating device 34, viewed in the direction of rotation, through a drying device in which the deposited metal is dried and a stripping device in which the dried metal is separated from the belt by means of rotating brushes and scrapers.
  • Figure 5 shows a guide of the endless belt 10,30 in the simplest possible form.
  • the endless belt is guided by two deflection rollers of different diameters 14 ', 11, which are arranged one above the other and at a distance from one another; the upper roller is designed as a drive and deflection roller 14 'and lies on the inner surface of the endless belt, it has a larger diameter than the lower deflection roller 11, which on the outer surface of the endless belt 10.30 is present.
  • the endless belt forms on both sides of the rollers 14 ', 11 flanking, depending loops which are provided for immersion in the solution or the electrolyte.
  • FIG. 6 it is also possible to provide a large number of small deflecting rollers instead of a single large upper roller, similar to that of FIG. 1, two additional deflecting rollers 12 'and 16' being arranged according to FIG rest the other deflection rollers 12, 13, 14, 15, 16 on the inner surface of the endless belt; roller 14 is provided as a deflection and drive roller;
  • the lower deflection roller 11, which lies against the outer surface of the endless belt 10, 30, is arranged at a distance below this roller.
  • the flanking loops of the endless belt 10, 30 intended for immersion in the solution or the electrolyte are formed on both sides of the roller 11, the two lower loop ends each having a further deflection roller 17, 18 to stabilize the belt movement.
  • Such Embodiment is particularly suitable for a positive transmission of the driving force from the drive roller to the endless belt.

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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)
  • Electrolytic Production Of Metals (AREA)
EP91117551A 1990-11-29 1991-10-15 Verfahren und Vorrichtung zum elektrolytischen Austragen von Metallen aus einer Metallionen enthaltenden Lösung sowie Elektrode zur Durchführung des Verfahrens Expired - Lifetime EP0487881B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4038065 1990-11-29
DE4038065A DE4038065C1 (enrdf_load_stackoverflow) 1990-11-29 1990-11-29

Publications (2)

Publication Number Publication Date
EP0487881A1 EP0487881A1 (de) 1992-06-03
EP0487881B1 true EP0487881B1 (de) 1996-03-13

Family

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EP91117551A Expired - Lifetime EP0487881B1 (de) 1990-11-29 1991-10-15 Verfahren und Vorrichtung zum elektrolytischen Austragen von Metallen aus einer Metallionen enthaltenden Lösung sowie Elektrode zur Durchführung des Verfahrens

Country Status (7)

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US (1) US5372683A (enrdf_load_stackoverflow)
EP (1) EP0487881B1 (enrdf_load_stackoverflow)
AT (1) ATE135417T1 (enrdf_load_stackoverflow)
CA (1) CA2056179A1 (enrdf_load_stackoverflow)
DE (2) DE4038065C1 (enrdf_load_stackoverflow)
MX (1) MX9102123A (enrdf_load_stackoverflow)
RU (1) RU2067624C1 (enrdf_load_stackoverflow)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5882502A (en) * 1992-04-01 1999-03-16 Rmg Services Pty Ltd. Electrochemical system and method
US5578183A (en) * 1995-05-11 1996-11-26 Regents Of The University Of California Production of zinc pellets
US5660706A (en) * 1996-07-30 1997-08-26 Sematech, Inc. Electric field initiated electroless metal deposition
US6080290A (en) * 1997-01-03 2000-06-27 Stuart Energy Systems Corporation Mono-polar electrochemical system with a double electrode plate
US6685819B2 (en) * 2001-07-10 2004-02-03 Pinnacle West Capital Corporation System and method for removing a solution phase metal from process liquor
JP2006124813A (ja) * 2004-11-01 2006-05-18 Sumitomo Titanium Corp Ｃａ還元によるＴｉの製造方法及び装置

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2344548A (en) * 1940-02-06 1944-03-21 Sunshine Mining Company Method and apparatus providing a continuously effective source for oligodynamic sterilization
FR2030516A5 (enrdf_load_stackoverflow) * 1969-03-31 1970-11-13 Norton Co
NL7008783A (enrdf_load_stackoverflow) * 1969-06-26 1970-12-29
GB1345411A (en) * 1971-01-08 1974-01-30 Imi Refiners Ltd Electrolytic refining and electrowinning of metals
JPS5227793B2 (enrdf_load_stackoverflow) * 1971-10-28 1977-07-22
US3970537A (en) * 1973-07-11 1976-07-20 Inland Steel Company Electrolytic treating apparatus
US3989604A (en) * 1975-10-15 1976-11-02 National Steel Corporation Method of producing metal strip having a galvanized coating on one side
GB2085856B (en) * 1980-10-01 1985-03-06 Hunter William Gold recovery process
US4647345A (en) * 1986-06-05 1987-03-03 Olin Corporation Metallurgical structure control of electrodeposits using ultrasonic agitation
DE3832674A1 (de) * 1988-09-27 1990-03-29 Kodak Ag Metallrueckgewinnungs-vorrichtung

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Publication number Publication date
US5372683A (en) 1994-12-13
ATE135417T1 (de) 1996-03-15
DE4038065C1 (enrdf_load_stackoverflow) 1991-10-17
CA2056179A1 (en) 1992-05-30
EP0487881A1 (de) 1992-06-03
MX9102123A (es) 1992-06-01
RU2067624C1 (ru) 1996-10-10
DE59107541D1 (de) 1996-04-18

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