EP0892086A1 - Anode on a basis of lead - Google Patents

Anode on a basis of lead Download PDF

Info

Publication number
EP0892086A1
EP0892086A1 EP98202316A EP98202316A EP0892086A1 EP 0892086 A1 EP0892086 A1 EP 0892086A1 EP 98202316 A EP98202316 A EP 98202316A EP 98202316 A EP98202316 A EP 98202316A EP 0892086 A1 EP0892086 A1 EP 0892086A1
Authority
EP
European Patent Office
Prior art keywords
anode
lead
catalyst element
catalyst
carrier
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.)
Withdrawn
Application number
EP98202316A
Other languages
German (de)
French (fr)
Inventor
Hermanus Johannes Jansen
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.)
MAGNETO-CHEMIE BV
Magneto Chemie NV
Original Assignee
MAGNETO-CHEMIE BV
Magneto Chemie NV
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 MAGNETO-CHEMIE BV, Magneto Chemie NV filed Critical MAGNETO-CHEMIE BV
Publication of EP0892086A1 publication Critical patent/EP0892086A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • 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
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
    • C25B11/02—Electrodes; Manufacture thereof not otherwise provided for characterised by shape or form
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
    • C25B11/02—Electrodes; Manufacture thereof not otherwise provided for characterised by shape or form
    • C25B11/03—Electrodes; Manufacture thereof not otherwise provided for characterised by shape or form perforated or foraminous

Definitions

  • the present invention relates to an anode suitable for oxygen evolution in an acid electrolyte, comprising a basic member of lead or a lead alloy connected to at least one catalyst element comprising a carrier with a catalyst for oxygen evolution.
  • Lead anodes or anodes of a lead alloy - generally designated in the following as lead anodes- are generally known in electrochemistry and are for instance used for the evolution of oxygen in methods for electrochemical recovery of metals from acid electrolytes.
  • a known process wherein such lead anodes are applied is electrochemical recovery of metals from sulphate solutions.
  • Other applications of lead anodes are the chrome-plating process and the process of the anodic oxidation of aluminium.
  • lead anodes undergo relatively great electrochemical wear whereby lead enters the solution, which results not only in contamination of the electrolyte but also in contamination of the product obtained at the cathode.
  • the dissolved lead moreover entails an impact on the environment when the electrolyte is further processed.
  • lead anodes must be replaced regularly as a result of the electrochemical wear.
  • Catalyst elements are herein in the form of catalyst particles, each comprising a catalyst for oxygen evolution fixed to a carrier particle, at least partly embedded in the basic member which comprises lead or a lead alloy.
  • the connection between the catalyst elements and the basic member is in this case non-releasable.
  • a drawback of such anodes is that the manufacture thereof involves a complicated method. It is hereby very difficult, if not practically impossible, to convert already existing anodes in simple manner to the anode according to the preamble.
  • the present invention has for its object to provide an anode which is suitable for oxygen evolution in an acid electrolyte, which is simple to manufacture and wherein existing lead anodes can be used as starting point for the manufacture.
  • the present invention provides an anode according to the preamble which is characterized in that the connection between the basic member and the catalyst element comprises a substantially releasable coupling.
  • Such a releasable coupling of the catalyst element to the basic member enables lead anodes to be coupled to and released from a catalyst element in simple manner. Not only an anode to be newly formed but also an already existing anode can hereby be 'converted' to an anode which is coupled to a catalyst element.
  • the existing lead anode is herein retained as element for current supply and as element for preserving mechanical stability. Coupled to a catalyst element, the anode is advantageously found not to possess the above stated drawbacks associated with lead anodes as such.
  • the catalyst element in particular, and especially the carrier thereof, is embodied as an element which can be coupled in simple manner to a basic member of lead or a lead alloy.
  • the carrier of the catalyst element is embodied in an advantageous embodiment as an expanded metal.
  • the carrier of the catalyst element is embodied as a plate-like element.
  • the carrier of the catalyst element is embodied as a wire-like element
  • the catalyst element is coupled in a preferred embodiment to the basic member using fixing assist means.
  • the fixing assist means can comprise many assist means known to the skilled person with which a catalyst element in the form of for instance a plate can be coupled to a basic member.
  • the catalyst element is however preferably coupled to the basic member using a bolt or a screw.
  • the carrier of the catalyst element preferably comprises a conductor. After coupling of the catalyst element to the basic member, the current in the anode is taken over from the basic member by the conductive carrier, so that the carrier functions as current transporter.
  • the carrier of the catalyst element comprises titanium.
  • the carrier can substantially comprise titanium or a titanium alloy.
  • the carrier and the fixing assist means, using which the catalyst element is coupled to the basic member comprise the same material.
  • the catalyst for oxygen evolution of the catalyst element preferably comprises at least one metal from the group of platinum, iridium, ruthenium, palladium, rhodium or oxides thereof.
  • the use of such a catalyst achieves a lower overvoltage for oxygen evolution.
  • the present invention also relates to an electrolysis process which is characterized in that an anode according to the present invention as described in the foregoing is used.
  • Such an electrolysis process can for instance include electrolytic recovery of metals, electrolytic chrome-plating of a surface or anodizing of aluminium.
  • a lead plate with an area of about 10 cm 2 - anode A - is placed on one side opposite a cathode and is loaded at 50°C with 5000 ampere per m 2 in sulphuric acid paste. Once the electrolysis is completed - after 148 hours - the loss of lead in the plate is measured.
  • a similar plate as described above is coated with a piece of titanium expanded metal with the same dimensions which is provided with a catalyst for oxygen evolution.
  • This anode is called anode B.
  • This anode is also subjected to the above electrolysis conditions and also in this case the loss of lead is measured.
  • a lead anode which is used in electrolytic metal recovery with dimensions of 900 mm x 1800 mm and a thickness of 15 mm is coupled to a titanium expanded metal on the side which is situated opposite the cathode during the electrolysis.
  • the titanium expanded metal has a dimension which is roughly equal to that of the lead anode and is coated with an iridium mixed oxide.
  • the diamond of the expanded metal is about 10 mm x 15 mm. Titanium plates with openings therein are spot-welded onto the expanded metal at regular mutual distances. Using titanium screws the expanded metal is screwed onto the lead anode through these openings, so that a simple and effective, though releasable, coupling is obtained between the anode and the expanded metal.
  • a bar anode of lead which is used in an electrolytic chrome-plating method has a length of 1500 mm and a diameter of 50 mm. Placed around this anode is a cylinder of titanium expanded metal which is coated with platinum. The titanium expanded metal is coupled to the bar anode using titanium bolts.
  • a lead anode which has been used in an electrolytic metal recovery process for some considerable time and is already displaying wear is coupled to a closed titanium plate on the side directed toward the cathode during electrolysis.
  • This titanium plate is provided on both sides with a catalyst for oxygen evolution.
  • the titanium plate is coupled to the anode using titanium screws.
  • the starting point in this example are two quarter-circular lead anodes which are placed mutually adjacently to form a semicircle and which are used in a radial cell for making copper foil as well as for galvanizing an - endless - metal belt.
  • These lead anodes are coated on the side situated opposite the cathode during electrolysis with a titanium plate which has been rolled into a - part - circular form and which is provided with threaded ends which can be received in corresponding openings in the lead anode and can be fixed using lock nuts.
  • This titanium plate is provided on the side directed toward the cathode with a catalyst for oxygen evolution in the form of a mixture of iridium oxide and tantalum oxide.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrodes For Compound Or Non-Metal Manufacture (AREA)

Abstract

An anode is described which is suitable for oxygen evolution in an acid electrolyte. This anode comprises a basic member of lead or a lead alloy connected to at least one catalyst element comprising a carrier with a catalyst for oxygen evolution. The connection between the basic member and the catalyst element herein comprises a substantially releasable coupling.
Also described is an electrolysis process, wherein the above stated anode is used.

Description

The present invention relates to an anode suitable for oxygen evolution in an acid electrolyte, comprising a basic member of lead or a lead alloy connected to at least one catalyst element comprising a carrier with a catalyst for oxygen evolution.
Lead anodes or anodes of a lead alloy - generally designated in the following as lead anodes- are generally known in electrochemistry and are for instance used for the evolution of oxygen in methods for electrochemical recovery of metals from acid electrolytes. A known process wherein such lead anodes are applied is electrochemical recovery of metals from sulphate solutions. Other applications of lead anodes are the chrome-plating process and the process of the anodic oxidation of aluminium.
A drawback to the use of lead anodes is that these anodes undergo relatively great electrochemical wear whereby lead enters the solution, which results not only in contamination of the electrolyte but also in contamination of the product obtained at the cathode. The dissolved lead moreover entails an impact on the environment when the electrolyte is further processed. Finally, lead anodes must be replaced regularly as a result of the electrochemical wear.
Another drawback of the use of lead anodes is that in electrochemical metal recovery the overvoltage of oxygen is high, which means that high energy cost are required for the process.
In EP-A-0 046 727 and EP-A-0 087 186 an attempt is made to provide a solution for the above stated problems and anodes as according to the preamble are described. Catalyst elements are herein in the form of catalyst particles, each comprising a catalyst for oxygen evolution fixed to a carrier particle, at least partly embedded in the basic member which comprises lead or a lead alloy. The connection between the catalyst elements and the basic member is in this case non-releasable. A drawback of such anodes is that the manufacture thereof involves a complicated method. It is hereby very difficult, if not practically impossible, to convert already existing anodes in simple manner to the anode according to the preamble.
The present invention has for its object to provide an anode which is suitable for oxygen evolution in an acid electrolyte, which is simple to manufacture and wherein existing lead anodes can be used as starting point for the manufacture. For this purpose the present invention provides an anode according to the preamble which is characterized in that the connection between the basic member and the catalyst element comprises a substantially releasable coupling.
Such a releasable coupling of the catalyst element to the basic member enables lead anodes to be coupled to and released from a catalyst element in simple manner. Not only an anode to be newly formed but also an already existing anode can hereby be 'converted' to an anode which is coupled to a catalyst element. The existing lead anode is herein retained as element for current supply and as element for preserving mechanical stability. Coupled to a catalyst element, the anode is advantageously found not to possess the above stated drawbacks associated with lead anodes as such.
The catalyst element in particular, and especially the carrier thereof, is embodied as an element which can be coupled in simple manner to a basic member of lead or a lead alloy. To this end the carrier of the catalyst element is embodied in an advantageous embodiment as an expanded metal.
In a following preferred embodiment the carrier of the catalyst element is embodied as a plate-like element.
Another possibility, which is likewise recommended, is that the carrier of the catalyst element is embodied as a wire-like element
The catalyst element, the carrier of which advantageously has one of the above mentioned embodiments, is coupled in a preferred embodiment to the basic member using fixing assist means.
The fixing assist means can comprise many assist means known to the skilled person with which a catalyst element in the form of for instance a plate can be coupled to a basic member. The catalyst element is however preferably coupled to the basic member using a bolt or a screw.
The carrier of the catalyst element preferably comprises a conductor. After coupling of the catalyst element to the basic member, the current in the anode is taken over from the basic member by the conductive carrier, so that the carrier functions as current transporter.
Although a plurality of metals, such as for instance tantalum, niobium and titanium, can be used for the carrier of the catalyst element, it is recommended that the carrier comprises titanium. Herein the carrier can substantially comprise titanium or a titanium alloy.
It is recommended that the carrier and the fixing assist means, using which the catalyst element is coupled to the basic member, comprise the same material.
Although many other metals can also be used as catalyst, the catalyst for oxygen evolution of the catalyst element preferably comprises at least one metal from the group of platinum, iridium, ruthenium, palladium, rhodium or oxides thereof. The use of such a catalyst achieves a lower overvoltage for oxygen evolution.
The present invention also relates to an electrolysis process which is characterized in that an anode according to the present invention as described in the foregoing is used.
Such an electrolysis process can for instance include electrolytic recovery of metals, electrolytic chrome-plating of a surface or anodizing of aluminium.
The present invention will be further elucidated hereinbelow with reference to a number of examples in which the effect of the releasable coupling of a lead anode to a catalyst element and a number of embodiments of the anode according to the present invention are successively explained.
EXAMPLE 1 Test for wear of anode
A lead plate with an area of about 10 cm2 - anode A - is placed on one side opposite a cathode and is loaded at 50°C with 5000 ampere per m2 in sulphuric acid paste. Once the electrolysis is completed - after 148 hours - the loss of lead in the plate is measured.
A similar plate as described above is coated with a piece of titanium expanded metal with the same dimensions which is provided with a catalyst for oxygen evolution. This anode is called anode B. This anode is also subjected to the above electrolysis conditions and also in this case the loss of lead is measured.
The results of the measurements on anode A and anode B are shown below:
Figure 00040001
The above results show clearly that the coupling of a lead anode to a catalyst element comprising a titanium expanded metal provided with a catalyst for oxygen evolution results in a considerably reduced wear of the lead anode.
EXAMPLE 2 Embodiment of anode according to the present invention (1)
A lead anode which is used in electrolytic metal recovery with dimensions of 900 mm x 1800 mm and a thickness of 15 mm is coupled to a titanium expanded metal on the side which is situated opposite the cathode during the electrolysis. The titanium expanded metal has a dimension which is roughly equal to that of the lead anode and is coated with an iridium mixed oxide. The diamond of the expanded metal is about 10 mm x 15 mm. Titanium plates with openings therein are spot-welded onto the expanded metal at regular mutual distances. Using titanium screws the expanded metal is screwed onto the lead anode through these openings, so that a simple and effective, though releasable, coupling is obtained between the anode and the expanded metal.
EXAMPLE 3 Embodiment of anode according to the present invention (2)
A bar anode of lead which is used in an electrolytic chrome-plating method has a length of 1500 mm and a diameter of 50 mm. Placed around this anode is a cylinder of titanium expanded metal which is coated with platinum. The titanium expanded metal is coupled to the bar anode using titanium bolts.
EXAMPLE 4 Embodiment of anode according to the present invention (3)
A lead anode which has been used in an electrolytic metal recovery process for some considerable time and is already displaying wear is coupled to a closed titanium plate on the side directed toward the cathode during electrolysis. This titanium plate is provided on both sides with a catalyst for oxygen evolution. The titanium plate is coupled to the anode using titanium screws.
EXAMPLE 5 Embodiment of anode according to the present invention (4)
The starting point in this example are two quarter-circular lead anodes which are placed mutually adjacently to form a semicircle and which are used in a radial cell for making copper foil as well as for galvanizing an - endless - metal belt. These lead anodes are coated on the side situated opposite the cathode during electrolysis with a titanium plate which has been rolled into a - part - circular form and which is provided with threaded ends which can be received in corresponding openings in the lead anode and can be fixed using lock nuts. This titanium plate is provided on the side directed toward the cathode with a catalyst for oxygen evolution in the form of a mixture of iridium oxide and tantalum oxide.

Claims (11)

  1. Anode suitable for oxygen evolution in an acid electrolyte, comprising a basic member of lead or a lead alloy connected to at least one catalyst element comprising a carrier with a catalyst for oxygen evolution, characterized in that the connection between the basic member and the catalyst element comprises a substantially releasable coupling.
  2. Anode as claimed in claim 1, characterized in that the carrier of the catalyst element is embodied as an expanded metal.
  3. Anode as claimed in claim 1, characterized in that the carrier of the catalyst element is embodied as a plate-like element.
  4. Anode as claimed in claim 1, characterized in that the carrier of the catalyst element is embodied as a wire-like element.
  5. Anode as claimed in one or more of the claims 1-4, characterized in that the catalyst element is coupled to the basic member using fixing assist means.
  6. Anode as claimed in one or more of the claims 1-5, characterized in that the catalyst element is coupled to the basic member using a bolt or a screw.
  7. Anode as claimed in one or more of the foregoing claims, characterized in that the carrier of the catalyst element comprises a conductor.
  8. Anode as claimed in one or more of the claims 1-3, characterized in that the carrier of the catalyst element comprises titanium.
  9. Anode as claimed in one or more of the claims 5-8, characterized in that the carrier and the fixing assist means comprise the same material.
  10. Anode as claimed in one or more of the foregoing claims, characterized in that the catalyst for oxygen evolution of the catalyst element comprises at least one metal from the group of platinum, iridium, ruthenium, palladium, rhodium or oxides thereof.
  11. Electrolysis process characterized in that an anode as claimed in one or more of the claims 1-10 is used.
EP98202316A 1997-07-11 1998-07-09 Anode on a basis of lead Withdrawn EP0892086A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1006552A NL1006552C1 (en) 1997-07-11 1997-07-11 Lead-based anode.
NL1006552 1997-07-11

Publications (1)

Publication Number Publication Date
EP0892086A1 true EP0892086A1 (en) 1999-01-20

Family

ID=19765327

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98202316A Withdrawn EP0892086A1 (en) 1997-07-11 1998-07-09 Anode on a basis of lead

Country Status (2)

Country Link
EP (1) EP0892086A1 (en)
NL (1) NL1006552C1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999057338A1 (en) * 1998-05-06 1999-11-11 Eltech Systems Corporation Lead electrode structure having mesh surface
US6352622B1 (en) 1998-05-06 2002-03-05 Eltech Systems Corporation Lead electrode
WO2002018676A1 (en) * 2000-08-25 2002-03-07 Eltech Systems Corporation Copper electrowinning

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0087185A1 (en) * 1982-02-18 1983-08-31 Eltech Systems Corporation Manufacture of electrode with lead base
US4512866A (en) * 1983-10-04 1985-04-23 Langley Robert C Titanium-lead anode for use in electrolytic processes employing sulfuric acid
EP0306627A1 (en) * 1987-08-11 1989-03-15 Heraeus Elektrochemie GmbH Electrochemical membrane cell with a plain electrode structure disposed at both sides of the membrane
EP0681038A1 (en) * 1994-05-03 1995-11-08 De Nora Permelec S.P.A. Electrolyzer for the production of sodium hypochlorite and chlorate equipped with improved electrodes

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0087185A1 (en) * 1982-02-18 1983-08-31 Eltech Systems Corporation Manufacture of electrode with lead base
US4512866A (en) * 1983-10-04 1985-04-23 Langley Robert C Titanium-lead anode for use in electrolytic processes employing sulfuric acid
EP0306627A1 (en) * 1987-08-11 1989-03-15 Heraeus Elektrochemie GmbH Electrochemical membrane cell with a plain electrode structure disposed at both sides of the membrane
EP0681038A1 (en) * 1994-05-03 1995-11-08 De Nora Permelec S.P.A. Electrolyzer for the production of sodium hypochlorite and chlorate equipped with improved electrodes

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999057338A1 (en) * 1998-05-06 1999-11-11 Eltech Systems Corporation Lead electrode structure having mesh surface
US6139705A (en) * 1998-05-06 2000-10-31 Eltech Systems Corporation Lead electrode
US6352622B1 (en) 1998-05-06 2002-03-05 Eltech Systems Corporation Lead electrode
US6368489B1 (en) 1998-05-06 2002-04-09 Eltech Systems Corporation Copper electrowinning
US6802948B2 (en) 1998-05-06 2004-10-12 Eltech Systems Corporation Copper electrowinning
WO2002018676A1 (en) * 2000-08-25 2002-03-07 Eltech Systems Corporation Copper electrowinning

Also Published As

Publication number Publication date
NL1006552C1 (en) 1999-01-12

Similar Documents

Publication Publication Date Title
US3278404A (en) Method and apparatus for cathodic protection
CA1188253A (en) Anode with lead base having partly embedded catalytic valve metal particles
DE2725066A1 (en) METHOD AND DEVICE FOR ELECTROLYZING
JP2617496B2 (en) Permanent anode for high current density galvanizing process
CH635369A5 (en) BIPOLAR ELECTRODES AND METHOD FOR THE PRODUCTION THEREOF.
DE2652152A1 (en) Electrodes for electrolytic devices - comprising conductive substrate, electrolyte-resistant coating with occlusions to improve electrode activity
EP0892086A1 (en) Anode on a basis of lead
US4470894A (en) Nickel electrodes for water electrolyzers
US4073702A (en) Electrochemical cells
EP1388595A1 (en) Process and apparatus for the formation of alkaline earth carbonates
Dew et al. The effect of Fe (II) and Fe (III) on the efficiency of copper electrowinning from dilute acid Cu (II) sulphate solutions with the chemelec cell: Part I. Cathodic and anodic polarisation studies
Pavlović et al. On the use of platinized and activated titanium anodes in some electrodeposition processes
GB1501893A (en) Continuous electrolytic colouring of a preanodised aluminium foil or strip
US4543174A (en) Method of making a catalytic lead-based oxygen evolving anode
DE2232903C3 (en) Process for the electrolytic refining of copper using titanium electrodes
DE3602683A1 (en) METHOD FOR CARRYING OUT HCL MEMBRANE ELECTROLYSIS
Peng et al. Achieving low voltage half electrolysis with a supercapacitor electrode
Gana et al. Direct electrorefining of copper scrap using an anode-support system in a bipolar cell
Wensley et al. Progressive degradation of noble metal coated titanium anodes in sulphuric acid and acidic copper sulphate electrolytes
Daolio et al. Secondary ion mass spectrometry characterization of IrO2–Ta2O5 thin films: effect of relative composition on electrode properties
Vuković et al. Electrochemical Investigation of an Electrodeposited and Thermally Treated Ruthenium Electrode in Alkaline Solution
JP3406403B2 (en) Electrode for strong acid water
GB1493731A (en) Rectifier and rectifying method
FI74997B (en) ELEKTROD FOER ELEKTROLYS AV ELEKTROLYTLOESNINGAR.
Chockalingam et al. Performance characteristics of different anode systems in EMD deposition

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

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 19990720

AKX Designation fees paid

Free format text: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

17Q First examination report despatched

Effective date: 20010425

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

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20011106