US3869312A - Electrodes and electrochemical processes - Google Patents

Electrodes and electrochemical processes Download PDF

Info

Publication number
US3869312A
US3869312A US394394A US39439473A US3869312A US 3869312 A US3869312 A US 3869312A US 394394 A US394394 A US 394394A US 39439473 A US39439473 A US 39439473A US 3869312 A US3869312 A US 3869312A
Authority
US
United States
Prior art keywords
film
coating
layer
compound
forming metal
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
US394394A
Inventor
Keith Graham Moss
Nicholas William Jame Pumphrey
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.)
Imperial Chemical Industries Ltd
Original Assignee
Imperial Chemical Industries Ltd
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 Imperial Chemical Industries Ltd filed Critical Imperial Chemical Industries Ltd
Application granted granted Critical
Publication of US3869312A publication Critical patent/US3869312A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/86Inert electrodes with catalytic activity, e.g. for fuel cells
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25BELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B11/00Electrodes; Manufacture thereof not otherwise provided for
    • C25B11/04Electrodes; Manufacture thereof not otherwise provided for characterised by the material
    • C25B11/051Electrodes formed of electrocatalysts on a substrate or carrier
    • C25B11/073Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material
    • C25B11/091Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material consisting of at least one catalytic element and at least one catalytic compound; consisting of two or more catalytic elements or catalytic compounds
    • C25B11/093Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material consisting of at least one catalytic element and at least one catalytic compound; consisting of two or more catalytic elements or catalytic compounds at least one noble metal or noble metal oxide and at least one non-noble metal oxide
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30Hydrogen technology
    • Y02E60/50Fuel cells

Definitions

  • ABSTRACT A method for manufacturing an electrode for use in electrochemical processes which comprises coating 21 support member made ofa film-forming metal or alloy thereof with a first layer of a mixture of a platinum group metal and a film-forming metal oxide and then coating said first layer with a second layer consisting of a film-forming metal oxide.
  • the present invention relates to electrodes for electrochemical processes. More particularly it relates to electrodes comprising a support member of a filmforming metal carrying a coating which is active in transferring an electric current from the support member to ions of an electrolyte and is resistant to electrochemical attack.
  • the present invention provides improved electrodes incorporating coatings comprising platinum group metal oxides.
  • the electrodes of the invention are very useful as anodes in cells for the electrolysis of alkali metal chloride solutions. They are particularly useful in cells with flowing mercury cathodes, because the elec trodes have a high resistance to damage by short-circuit contact with the cathode, such as may occur accidentally even during the normal course of operation in these cells.
  • the electrodes can also be used in other electrochemical processes, including other electrolytic processes, electrocatalysis, as for instance in fuel cells, electrosynthesis and cathodic protection.
  • an electrode for use in electrochemical processes which comprises a support member made of a film-forming metal or alloy and a coating thereon consisting of a layer of a mixture of the oxide(s) of at least one platinum group metal in a proportion of -80 percent by weight and a film-forming metal oxide and superimposed on the said layer a layer of a film-forming metal oxide.
  • the ratio of platinum group metal oxideszfilm-forming metal oxide in the layer of the said mixture is not less than 121 but is less than 2:1 by weight.
  • a film-forming metal we mean one of the metals titanium, zirconium, niobium, tantalum and tungsten.
  • a film-forming alloy we mean an alloy containing a major proportion of one of these metals and having anodic polarisation properties similar to the commercially pure metal.
  • the support member of the electrode is preferably made of titanium or a titanium alloy having anodic polarisation properties similar to those of titanium.
  • oxide(s) of at least one platinum group metal we mean the oxide(s) of at least one of the metals ruthenium, rhodium, palladium, osmium, iridium and platinum.
  • the layer of the said mixture consists of ruthenium dioxide and titanium dioxide and the superimposed layer consists of titanium dioxide.
  • the preferred method of forming the layer of mixed oxides on the support member is as follows.
  • a coating of a paint composition comprising a thermally decomposable compound of at least one platinum group metal and a thermally decomposable organo-compound of a film-forming metal in an organic liquid vehicle and optionally also comprising a reducing agent, e.g., linalool, is applied to the support member, the coating is dried by evaporation of the liquid vehicle and the coated support is then heated in-an oxidising atmosphere, e.g., in air, at a temperature of at least 350C and preferably in the range 400-550C to convert the compounds of the platinum group metals and the film-forming metal to oxides of these metals.
  • a reducing agent e.g., linalool
  • Further coats of the paint composition may then be applied to the coated support, dried and heated in the same manner to increase the thickness of the mixed oxide layer to any desired extent.
  • electrolysing alkali metal chloride solutions we prefer to build up a thickness of this layer in the range 10-l5g/m of the coated surface of the support member. This thickness is, however, in no way critical. Thinner or thicker coatings may be employed and the thickness will generally be chosen having regard to the wear to which the electrode will be submitted during use in the cell, which itself will be related inter alia to the current density at which the electrode will be required to operate.
  • the preferred method of forming the superimposed layer of film-forming metal oxide is by applying over the mixed oxide layer a coating of a thermally decomposable organo-compound of the film-forming metal in an organic liquid vehicle, drying the coating by evaporation of the liquid vehicle and then heating the coating in an oxidising atmosphere, e.g., air, to convert the organo-compound of the film-forming metal to the oxide of the metal.
  • the preferred thickness of this superimposed layer of film-forming metal oxide is in the range 2-10g/m of the coated surface.
  • the desired thickness of this layer may be obtained by adjusting the viscosity of the coating composition by adding more or less of the organic liquid vehicle and/or by repeated application of thinner layers of coating composition, drying and heating each coating, to build up the desired thickness.
  • thermally decomposable organo-compounds of the film-forming metals employed in forming the superimposed layer of film-forming metal oxide in accordance with the preceding paragraph are most suitably the alkyl titanates, the alkyl halotitanates wherein the halogen is chlorine, bromine or fluorine (alternatively known as titanium alkoxides and alkoxy-halides) and the corresponding alkyl compounds of other filmforming metals.
  • Other suitable thermally decomposable organo-compounds are resinates of the film- .forming metals.
  • the preferred compounds are the alkyl titanates and halotitanates, especially those in which the alkyl groups contain 2-4 carbon atoms each.
  • Coatings of these preferred compounds applied in an organic liquid vehicle as aforesaid are suitably dried at a temperature of lOO-200C and then heated in an oxidising atmosphere at 250800C, preferably at 3505 50C, to convert the titanate compounds to titanium dioxide.
  • thermally decomposable compounds of the film-forming metals listed in the preceding paragraph may also be employed in the paint compositions used for forming the under-layer of mixed oxides on the electrode support member.
  • the alkyl titanates and the alkyl halotitanates wherein the halogen is chlorine, bromine or fluorine, especially those in which the alkyl groups contain 2-4 carbon atoms each are preferred.
  • the thermally decomposable compounds of the platinum group metals used in these paint compositions may suitably be halides, e.g., ruthenium trichloride, halo-acid complexes, e.g., hexachloroplatinic acid, or resinates of these metals.
  • the preferred platinum group metal compound is ruthenium trichloride.
  • the invention is further illustrated by the following Example 5.
  • EXAMPLE 1 A strip of titanium 35 cm long, cross section 6 mm X 1 mm was etched in oxalic acid solution, washed, dried and then painted with a mixture of 4.3g partly hydrated ruthenium trichloride, 12.0g n-pentanol and 6.4g tetrabutyl ortho titanate. The paint layer was dried at 180C and then fired by heating in air at 450C for 15 minutes. A total of six layers of this paint was applied, each layer being dried and heated in the same manner, to give a loading on the titanium surface of l4g/m of a coating consisting of 60 percent ruthenium dioxide and 40 percent titanium dioxide by weight.
  • Samples cut from the coated strip were tested as anodes for chlorine production in sodium chloride brine containing 21.5% NaCl at pH 2-3 and a temperature of 65C.
  • the samples operated with low overpotential (50 mV at a current density of 8 kA/m and they also showed excellent resistance to damage when contacted with the cathode amalgam in a mercury cell electrolysing sodium chloride brine.
  • EXAMPLE 2 An anode whose working surface was in the form of a grid made up oftitanium strips and having a projected area of 0.1 m was in oxalic acid solution for 16 hours, washed and dried. The anode grid was then sprayed with a paint composition consisting of 60.5 g ruthenium trichloride and 90.0 g tetra-n-butyl ortho titanate in 300 g n-pentanol. The paint layer was dried in an oven at 180C and was then converted to a layer of composition 60% RuO /40% TiO by weight by heating in air in a furnace at 450C for 20 minutes.
  • a further five layers of the same paint composition were then sprayed on to the anode, each layer being dried and then fired by heating in air as was the first layer.
  • An outer layer consisting of titanium dioxide alone was then applied to the anode grid by spraying on to it three coats of a paint composition consisting of g tetra-n-butyl titanate in 75 g n-pentanol, each being dried at 180C and then fired in air at 450C for 20 minutes.
  • the total loading of oxides deposited on the titanium grid was then 32 g/m projected area.
  • the coated titanium anode was installed in a mercury-cathode cell electrolysing sodium brine, as a replacement for a graphite anode, and after operating satisfactorily for six months with an anode current of up to 900 amp. there was no apparent wear nor decline in performance.
  • EXAMPLE 3 A titanium grid anode of 0.1 m projected area was coated as in Example 2 except that the paint composition used for the first six coats consisted of 55 g ruthenium trichloride and 101 g tetra-n-butyl ortho titanate in 300 g n-pentanol. This composition, after drying and firing, produced an underlayer on the titanium grid of composition 55% RuO /45% TiO by weight. The outer layer consisting of titanium dioxide alone was then deposited as in Example 2. This anode was also operated in a mercury-cathode cell electrolysing sodium chloride brine and also showed no signs of wear nor decline in performance after six months use with an anode current of up to 900 amp.
  • the said support member is made of titanium or a titanium alloy having anodic polarisation properties similar to those of titanium.
  • step (1) the thermally decomposable compound of at least one platinum group metal is ruthenium trichloride.
  • step (1) the temperature at which each coating is heated in an oxidising atmosphere is in the range 400550C.
  • step (1 the number of coatings of the said composition applied, dried and heated on the support member is sufficient to build up a layer of mixed oxides amounting to 10-15 g/m of the coated surface of this support memher.
  • step (1) the thermally-decomposable organo-compound of a film-forming metal is an alkyl titanate or an alkyl halotitanate wherein the halogen is chlorine, bromine or fluorine.
  • step (2) 8. A method according to claim 1, wherein the total amount of coating which is applied over the said layer of mixed oxides is sufficient to produce in step (2) a layer of film-forming metal oxide amounting to 2-10 g/m of the coated surface.

Abstract

A method for manufacturing an electrode for use in electrochemical processes which comprises coating a support member made of a film-forming metal or alloy thereof with a first layer of a mixture of a platinum group metal and a film-forming metal oxide and then coating said first layer with a second layer consisting of a film-forming metal oxide.

Description

Unite States Patent [19] Moss et a1.
11] 3,869,312 Mar. 4, 1975 ELECTRODES AND ELECTROCHEMICAL PROCESSES [75] Inventors: Keith Graham Moss; Nicholas William James Pumphrey, both of Runcorn, England [73] Assignee: Imperial Chemical Industries Limited, London, England [22] Filed: Sept. 4, 1973 [21] Appl. N0.: 394,394
Related US. Application Data [62] Division of Ser. No. 233,354, March 9, 1972.
[30] Foreign Application Priority Data Mar. 18, 1971 Great Britain 7211/71 [52] 1.1.8. Cl. 117/215, 117/221, 204/290 F [51] int. Cl B44d 1/18 [58] Field of Search 117/217, 215, 221;
[56] References Cited UNITED STATES PATENTS 3,562,008 2/1971 Martinsons 204/290 F Primary ExaminerCameron K. Weiffenbach Attorney, Agent, or Firm-Cushman, Darby & Cushman [57] ABSTRACT A method for manufacturing an electrode for use in electrochemical processes which comprises coating 21 support member made ofa film-forming metal or alloy thereof with a first layer of a mixture of a platinum group metal and a film-forming metal oxide and then coating said first layer with a second layer consisting of a film-forming metal oxide.
11 Claims, No Drawings ELECTRODES AND ELECTROCHEMICAL PROCESSES CROSS-REFERENCE TO A RELATED APPLICATION This is a division, of application Ser. No. 233,354 filed Mar. 9, 1972.
The present invention relates to electrodes for electrochemical processes. More particularly it relates to electrodes comprising a support member of a filmforming metal carrying a coating which is active in transferring an electric current from the support member to ions of an electrolyte and is resistant to electrochemical attack.
It is known to employ oxides of the platinum group metals as coatings on electrodes of the aforesaid type because they have a high intrinsic resistance to electrochemical dissolution in a variety of corrosive media and they are active in discharging ions from an electrolyte. The present invention provides improved electrodes incorporating coatings comprising platinum group metal oxides. The electrodes of the invention are very useful as anodes in cells for the electrolysis of alkali metal chloride solutions. They are particularly useful in cells with flowing mercury cathodes, because the elec trodes have a high resistance to damage by short-circuit contact with the cathode, such as may occur accidentally even during the normal course of operation in these cells. The electrodes can also be used in other electrochemical processes, including other electrolytic processes, electrocatalysis, as for instance in fuel cells, electrosynthesis and cathodic protection.
According to the present invention we provide an electrode for use in electrochemical processes which comprises a support member made of a film-forming metal or alloy and a coating thereon consisting of a layer of a mixture of the oxide(s) of at least one platinum group metal in a proportion of -80 percent by weight and a film-forming metal oxide and superimposed on the said layer a layer of a film-forming metal oxide.
In a preferred form of the electrode the ratio of platinum group metal oxideszfilm-forming metal oxide in the layer of the said mixture is not less than 121 but is less than 2:1 by weight.
By a film-forming metal we mean one of the metals titanium, zirconium, niobium, tantalum and tungsten. By a film-forming alloy we mean an alloy containing a major proportion of one of these metals and having anodic polarisation properties similar to the commercially pure metal. The support member of the electrode is preferably made of titanium or a titanium alloy having anodic polarisation properties similar to those of titanium.
By the oxide(s) of at least one platinum group metal we mean the oxide(s) of at least one of the metals ruthenium, rhodium, palladium, osmium, iridium and platinum.
In a preferred form of the electrode according to the invention the layer of the said mixture consists of ruthenium dioxide and titanium dioxide and the superimposed layer consists of titanium dioxide.
The preferred method of forming the layer of mixed oxides on the support member is as follows. A coating of a paint composition comprising a thermally decomposable compound of at least one platinum group metal and a thermally decomposable organo-compound of a film-forming metal in an organic liquid vehicle and optionally also comprising a reducing agent, e.g., linalool, is applied to the support member, the coating is dried by evaporation of the liquid vehicle and the coated support is then heated in-an oxidising atmosphere, e.g., in air, at a temperature of at least 350C and preferably in the range 400-550C to convert the compounds of the platinum group metals and the film-forming metal to oxides of these metals. Further coats of the paint composition may then be applied to the coated support, dried and heated in the same manner to increase the thickness of the mixed oxide layer to any desired extent. For example for electrodes that are to be used as anodes in mercury-cathode cells electrolysing alkali metal chloride solutions we prefer to build up a thickness of this layer in the range 10-l5g/m of the coated surface of the support member. This thickness is, however, in no way critical. Thinner or thicker coatings may be employed and the thickness will generally be chosen having regard to the wear to which the electrode will be submitted during use in the cell, which itself will be related inter alia to the current density at which the electrode will be required to operate.
The preferred method of forming the superimposed layer of film-forming metal oxide is by applying over the mixed oxide layer a coating of a thermally decomposable organo-compound of the film-forming metal in an organic liquid vehicle, drying the coating by evaporation of the liquid vehicle and then heating the coating in an oxidising atmosphere, e.g., air, to convert the organo-compound of the film-forming metal to the oxide of the metal. The preferred thickness of this superimposed layer of film-forming metal oxide is in the range 2-10g/m of the coated surface. The desired thickness of this layer may be obtained by adjusting the viscosity of the coating composition by adding more or less of the organic liquid vehicle and/or by repeated application of thinner layers of coating composition, drying and heating each coating, to build up the desired thickness.
The thermally decomposable organo-compounds of the film-forming metals employed in forming the superimposed layer of film-forming metal oxide in accordance with the preceding paragraph are most suitably the alkyl titanates, the alkyl halotitanates wherein the halogen is chlorine, bromine or fluorine (alternatively known as titanium alkoxides and alkoxy-halides) and the corresponding alkyl compounds of other filmforming metals. Other suitable thermally decomposable organo-compounds are resinates of the film- .forming metals. The preferred compounds are the alkyl titanates and halotitanates, especially those in which the alkyl groups contain 2-4 carbon atoms each. Coatings of these preferred compounds applied in an organic liquid vehicle as aforesaid are suitably dried at a temperature of lOO-200C and then heated in an oxidising atmosphere at 250800C, preferably at 3505 50C, to convert the titanate compounds to titanium dioxide.
Any of the thermally decomposable compounds of the film-forming metals listed in the preceding paragraph may also be employed in the paint compositions used for forming the under-layer of mixed oxides on the electrode support member. Again the alkyl titanates and the alkyl halotitanates wherein the halogen is chlorine, bromine or fluorine, especially those in which the alkyl groups contain 2-4 carbon atoms each, are preferred. The thermally decomposable compounds of the platinum group metals used in these paint compositions may suitably be halides, e.g., ruthenium trichloride, halo-acid complexes, e.g., hexachloroplatinic acid, or resinates of these metals. The preferred platinum group metal compound is ruthenium trichloride.
The invention is further illustrated by the following Example 5.
EXAMPLE 1 A strip of titanium 35 cm long, cross section 6 mm X 1 mm was etched in oxalic acid solution, washed, dried and then painted with a mixture of 4.3g partly hydrated ruthenium trichloride, 12.0g n-pentanol and 6.4g tetrabutyl ortho titanate. The paint layer was dried at 180C and then fired by heating in air at 450C for 15 minutes. A total of six layers of this paint was applied, each layer being dried and heated in the same manner, to give a loading on the titanium surface of l4g/m of a coating consisting of 60 percent ruthenium dioxide and 40 percent titanium dioxide by weight. Over this mixed oxide coating was painted a mixture of 5g tetrabutyl ortho titanate in 5g n-pentanol. This paint was also dried at 180C and then fired by heated in air at 450C for minutes. A total of three layers of this second paint was applied, each layer being dried and heated in the same manner, to give a loading of 4g/m of titanium dioxide over the mixed oxide layer.
Samples cut from the coated strip were tested as anodes for chlorine production in sodium chloride brine containing 21.5% NaCl at pH 2-3 and a temperature of 65C. The samples operated with low overpotential (50 mV at a current density of 8 kA/m and they also showed excellent resistance to damage when contacted with the cathode amalgam in a mercury cell electrolysing sodium chloride brine.
EXAMPLE 2 An anode whose working surface was in the form of a grid made up oftitanium strips and having a projected area of 0.1 m was in oxalic acid solution for 16 hours, washed and dried. The anode grid was then sprayed with a paint composition consisting of 60.5 g ruthenium trichloride and 90.0 g tetra-n-butyl ortho titanate in 300 g n-pentanol. The paint layer was dried in an oven at 180C and was then converted to a layer of composition 60% RuO /40% TiO by weight by heating in air in a furnace at 450C for 20 minutes. A further five layers of the same paint composition were then sprayed on to the anode, each layer being dried and then fired by heating in air as was the first layer. An outer layer consisting of titanium dioxide alone was then applied to the anode grid by spraying on to it three coats of a paint composition consisting of g tetra-n-butyl titanate in 75 g n-pentanol, each being dried at 180C and then fired in air at 450C for 20 minutes. The total loading of oxides deposited on the titanium grid was then 32 g/m projected area.
The coated titanium anode was installed in a mercury-cathode cell electrolysing sodium brine, as a replacement for a graphite anode, and after operating satisfactorily for six months with an anode current of up to 900 amp. there was no apparent wear nor decline in performance.
EXAMPLE 3 A titanium grid anode of 0.1 m projected area was coated as in Example 2 except that the paint composition used for the first six coats consisted of 55 g ruthenium trichloride and 101 g tetra-n-butyl ortho titanate in 300 g n-pentanol. This composition, after drying and firing, produced an underlayer on the titanium grid of composition 55% RuO /45% TiO by weight. The outer layer consisting of titanium dioxide alone was then deposited as in Example 2. This anode was also operated in a mercury-cathode cell electrolysing sodium chloride brine and also showed no signs of wear nor decline in performance after six months use with an anode current of up to 900 amp.
We claim:
1. A method for manufacture of an electrode for use in electrochemical processes wherein said electrode comprises a support member made of a film-forming metal or an alloy thereof having a coating thereon consisting of at least one layer of a mixture of the oxide of at least one platinum group metal in a proportion of 20-80 percent by weight and a film-forming metal oxide and superimposed on the said layer a layer consisting of a film-forming metal oxide which comprises the steps of (1) applying on said support member at least one coating of a composition comprising a thermally-decomposable compound of at least one platinum group metal and a thermally-decomposable organo-compound of a film-forming metal in an organic liquid vehicle, drying each coating by evaporation of the liquid vehicle and then heating each coating in an oxidizing atmosphere at a temperature of at least 350C to convert the compounds of the platinum group metals and the film-forming metal to mixed oxides of these metals, and (2) applying over the layer of mixed oxides thus produced on the support member at least one coating of a thermally decomposable organocompound of a film-forming metal in an organic liquid vehicle, said last-mentioned coating being free from any platinum group metal or compound thereof, drying each coating by evaporation of the liquid vehicle and then heating each coating in an oxidizing atmosphere to convert the organo-compound of the film-forming metal to the oxide of the metal.
2. A method according to claim 1, wherein the said support member is made of titanium or a titanium alloy having anodic polarisation properties similar to those of titanium.
3. A method according to claim 1, wherein in step (1) the thermally decomposable compound of at least one platinum group metal is ruthenium trichloride.
4. A method according to claim 1, wherein in step (1) the temperature at which each coating is heated in an oxidising atmosphere is in the range 400550C.
5. A method according to claim 1, wherein in step (1 the number of coatings of the said composition applied, dried and heated on the support member is sufficient to build up a layer of mixed oxides amounting to 10-15 g/m of the coated surface of this support memher.
6. A method according to claim 1, wherein in step (1) the thermally-decomposable organo-compound of a film-forming metal is an alkyl titanate or an alkyl halotitanate wherein the halogen is chlorine, bromine or fluorine.
7. A method according to claim 1, wherein the proportions of platinum group metal compoundsand filmforming metal compound in the said composition employed in step (1) are chosen so that the ratio of platinum group metal oxideszfilm-forming metal oxide in the said layer of mixed oxides produced in step (1) is not less than 1:1 but is less than 2:1 by weight.
8. A method according to claim 1, wherein the total amount of coating which is applied over the said layer of mixed oxides is sufficient to produce in step (2) a layer of film-forming metal oxide amounting to 2-10 g/m of the coated surface.

Claims (11)

1. A METHOD FOR MANUFACTURE OF AN ELECTRODE FOR USE IN ELECTROCHEMICAL PROCESSES WHEREIN SAID ELECTRODE COMPRISES A SUPPORT MEMBER MADE OF A FILM-FORMING METAL OR AN ALLOY THEREOF HAVING A COATING THEREON CONSISTING OF AT LEAST ONE LAYER OF A MIXTURE OF THE OXIDE OF AT LEAST ONE PLATINUM GROUP METAL IN A PROPORTION OF 20-80 PERCENT BY WEIGHT AND A FILMFORMING METAL OXIDE AND SUPERIMPOSED ON THE SAID LAYER A LAYER CONSISTING OF A FILM-FORMING METAL OXIDE WHICH COMPRISES THE STEPS OF (1) APPLYING ON SAID SUPPORT MEMBER AT LEAST ONE COATING OF A COMPOSITION COMPRISING A THERMALLYDECOMPOSABLE COMPOUND OF AT LEAST ONE PLATINUM GROUP METAL AND A THERMALLY-DECOMPOSABLE ORGANO-COMPOUND OF A FILMFORMING METAL IN AN ORGAIC LIQUID VEHICLE, DRYING EACH COATING BY EVAPORATION OF THE LIQUID VEHICLE AND THEN HEATING EACH COATING IN AN OXIDIZING ATMOSPHERE AT A TEMPERATURE OF AT LEAST 350*C. TO CONVERT THE COMPOUNDS OF THE PLATINUM GROUP METALS AND THE FILM-FORMING METAL TO MIXED OXIDES OF THESE METALS, AND (2) APPLYING OVER THE LAYER OF MIXED OXIDES THUS PRODUCED ON THE SUPPORT MEMBER AT LEAST ONE COATING OF A THERMALLY DECOMPOSABLE ORGANO-COMPOUND OF A FILM-FORMING METAL IN AN ORGAIC LIQUID VEHICLE, SAID LAST-MENTIONED CAOTING BEING FREE FROM ANY PLATINUM GROUP METAL OR COMPOUND THEREOF, DRYING EACH COATING BY EVAPORATION OF THE LIQUID VEHICLE AND THEN HEATING EACH COTAING IN AN OXIDIZING ATMOSPHERE TO CONVENT THE ORGANO-COMPOUND OF THE FILM-FORMING METAL TO THE OXIDE OF THE METAL.
2. A method according to claim 1, wherein the said support member is made of titanium or a titanium alloy having anodic polarisation properties similar to those of titanium.
3. A method according to claim 1, wherein in step (1) the thermally decomposable compound of at least one platinum group metal is ruthenium trichloride.
4. A method according to claim 1, wherein in step (1) the temperature at which each coating is heated in an oxidising atmosphere is in the range 400*-550*C.
5. A method according to claim 1, wherein in step (1) the number of coatings of the said composition applied, dried and heated on the support member is sufficient to build up a layer of mixed oxides amounting to 10-15 g/m2 of the coated surface of this support member.
6. A method according to claim 1, wherein in step (1) the thermally-decomposable organo-compound of a film-forming metal is an alkyl titanate or an alkyl halotitanate wherein the halogen is chlorine, bromine or fluorine.
7. A method according to claim 1, wherein the proportions of platinum group metal compounds and film-forming metal compound in the said composition employed in step (1) are chosen so that the ratio of platinum group metal oxides:film-forming metal oxide in the said layer of mixed oxides produced in step (1) is not less than 1:1 but is less than 2:1 by weight.
8. A method according to claim 1, wherein the total amount of coating which is applied over the said layer of mixed oxides is sufficient to produce in step (2) a layer of film-forming metal oxide amounting to 2-10 g/m2 of the coated surface.
9. A method according to claim 1, wherein in step (2) the thermally decomposable organo-compound of a film-forming metal is an alkyl titanate or an alkyl halotitanate wherein the halogen is chlorine, bromine or fluorine.
10. A method according to claim 9, wherein in step (2) each coating is dried at 100*-200*C and is then heated at 250*-800*C in an oxidising atmosphere.
11. A method according to claim 10, wherein in step (2) each coating after drying is heated at 350*-550*C in an oxidising atmosphere.
US394394A 1971-03-18 1973-09-04 Electrodes and electrochemical processes Expired - Lifetime US3869312A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB721171 1971-03-18
US23335472A 1972-03-09 1972-03-09

Publications (1)

Publication Number Publication Date
US3869312A true US3869312A (en) 1975-03-04

Family

ID=9828761

Family Applications (1)

Application Number Title Priority Date Filing Date
US394394A Expired - Lifetime US3869312A (en) 1971-03-18 1973-09-04 Electrodes and electrochemical processes

Country Status (21)

Country Link
US (1) US3869312A (en)
JP (1) JPS559471B1 (en)
AR (1) AR194834A1 (en)
AT (1) AT312633B (en)
AU (1) AU463572B2 (en)
BE (1) BE780756A (en)
BR (1) BR7201555D0 (en)
CA (1) CA976505A (en)
CH (1) CH578625A5 (en)
DD (1) DD99934A5 (en)
DE (1) DE2213083A1 (en)
ES (1) ES400915A1 (en)
FR (1) FR2130419B1 (en)
GB (1) GB1352872A (en)
IL (1) IL38958A (en)
IT (1) IT950343B (en)
MY (1) MY7400318A (en)
NL (1) NL7203580A (en)
NO (1) NO140235C (en)
TR (1) TR17134A (en)
ZA (1) ZA721481B (en)

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3969216A (en) * 1974-12-27 1976-07-13 Doreen Veronica Barrett Flotation separation
US4005004A (en) * 1974-09-27 1977-01-25 Asahi Kasei Kogyo Kabushiki Kaisha Electrode coating consisting of a solid solution of a noble metal oxide, titanium oxide, and zirconium oxide
US4039400A (en) * 1974-10-29 1977-08-02 Marston Excelsior Limited Method of forming electrodes
US4112140A (en) * 1977-04-14 1978-09-05 The Dow Chemical Company Electrode coating process
FR2433595A1 (en) * 1978-08-14 1980-03-14 Dow Chemical Co METHOD FOR COATING ELECTRODES WITH A RUTHENIUM DERIVATIVE
US4331528A (en) * 1980-10-06 1982-05-25 Diamond Shamrock Corporation Coated metal electrode with improved barrier layer
US4585540A (en) * 1984-09-13 1986-04-29 Eltech Systems Corporation Composite catalytic material particularly for electrolysis electrodes and method of manufacture
US4615913A (en) * 1984-03-13 1986-10-07 Kaman Sciences Corporation Multilayered chromium oxide bonded, hardened and densified coatings and method of making same
US4871703A (en) * 1983-05-31 1989-10-03 The Dow Chemical Company Process for preparation of an electrocatalyst
US5707715A (en) * 1996-08-29 1998-01-13 L. Pierre deRochemont Metal ceramic composites with improved interfacial properties and methods to make such composites
US6000982A (en) * 1995-07-31 1999-12-14 Casio Computer Co., Ltd. Method of manufacturing a cold-cathode for a discharge device
US6143432A (en) * 1998-01-09 2000-11-07 L. Pierre deRochemont Ceramic composites with improved interfacial properties and methods to make such composites
US6323549B1 (en) 1996-08-29 2001-11-27 L. Pierre deRochemont Ceramic composite wiring structures for semiconductor devices and method of manufacture
US20030085199A1 (en) * 2001-11-08 2003-05-08 Korea Atomic Energy Research Institute & Technology Winners Co., Ltd. Method for manufacturing catalytic oxide anode using high temperature sintering
US20040031692A1 (en) * 1999-06-28 2004-02-19 Kenneth Hardee Coatings for the inhibition of undesirable oxidation in an electrochemical cell
US20090288958A1 (en) * 2008-05-24 2009-11-26 Phelps Dodge Corporation Electrochemically active composition, methods of making, and uses thereof
US20130228450A1 (en) * 2010-12-22 2013-09-05 Industrie De Nora S.P.A. Electrode for electrolytic cell
US8580091B2 (en) 2010-10-08 2013-11-12 Water Star, Inc. Multi-layer mixed metal oxide electrode and method for making same
CN104005047A (en) * 2014-06-11 2014-08-27 中国船舶重工集团公司第七二五研究所 Novel mixed metal oxide electrode for low-temperature sea water electrolysis antifouling
CN106099047A (en) * 2016-08-25 2016-11-09 深圳市贝特瑞纳米科技有限公司 A kind of surface coating method of electrode material and application thereof
US11668017B2 (en) 2018-07-30 2023-06-06 Water Star, Inc. Current reversal tolerant multilayer material, method of making the same, use as an electrode, and use in electrochemical processes

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3793164A (en) * 1973-04-19 1974-02-19 Diamond Shamrock Corp High current density brine electrolysis
JPS582175A (en) * 1981-06-27 1983-01-07 フジテック株式会社 Controller for elevator
EP0174413A1 (en) * 1984-09-17 1986-03-19 Eltech Systems Corporation Composite catalytic material particularly for electrolysis electrodes and method of manufacture

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3562008A (en) * 1968-10-14 1971-02-09 Ppg Industries Inc Method for producing a ruthenium coated titanium electrode
US3616445A (en) * 1967-12-14 1971-10-26 Electronor Corp Titanium or tantalum base electrodes with applied titanium or tantalum oxide face activated with noble metals or noble metal oxides
US3645862A (en) * 1967-09-26 1972-02-29 Imp Metal Ind Kynoch Ltd Method of making an electrode
US3663280A (en) * 1968-04-02 1972-05-16 Ici Ltd Electrodes for electrochemical processes
US3684543A (en) * 1970-11-19 1972-08-15 Patricia J Barbato Recoating of electrodes
US3711385A (en) * 1970-09-25 1973-01-16 Chemnor Corp Electrode having platinum metal oxide coating thereon,and method of use thereof
US3773554A (en) * 1970-03-18 1973-11-20 Ici Ltd Electrodes for electrochemical processes
US3773555A (en) * 1969-12-22 1973-11-20 Imp Metal Ind Kynoch Ltd Method of making an electrode

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1195871A (en) * 1967-02-10 1970-06-24 Chemnor Ag Improvements in or relating to the Manufacture of Electrodes.

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3645862A (en) * 1967-09-26 1972-02-29 Imp Metal Ind Kynoch Ltd Method of making an electrode
US3616445A (en) * 1967-12-14 1971-10-26 Electronor Corp Titanium or tantalum base electrodes with applied titanium or tantalum oxide face activated with noble metals or noble metal oxides
US3663280A (en) * 1968-04-02 1972-05-16 Ici Ltd Electrodes for electrochemical processes
US3562008A (en) * 1968-10-14 1971-02-09 Ppg Industries Inc Method for producing a ruthenium coated titanium electrode
US3718551A (en) * 1968-10-14 1973-02-27 Ppg Industries Inc Ruthenium coated titanium electrode
US3773555A (en) * 1969-12-22 1973-11-20 Imp Metal Ind Kynoch Ltd Method of making an electrode
US3773554A (en) * 1970-03-18 1973-11-20 Ici Ltd Electrodes for electrochemical processes
US3711385A (en) * 1970-09-25 1973-01-16 Chemnor Corp Electrode having platinum metal oxide coating thereon,and method of use thereof
US3684543A (en) * 1970-11-19 1972-08-15 Patricia J Barbato Recoating of electrodes

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4005004A (en) * 1974-09-27 1977-01-25 Asahi Kasei Kogyo Kabushiki Kaisha Electrode coating consisting of a solid solution of a noble metal oxide, titanium oxide, and zirconium oxide
US4039400A (en) * 1974-10-29 1977-08-02 Marston Excelsior Limited Method of forming electrodes
US3969216A (en) * 1974-12-27 1976-07-13 Doreen Veronica Barrett Flotation separation
US4112140A (en) * 1977-04-14 1978-09-05 The Dow Chemical Company Electrode coating process
FR2387300A1 (en) * 1977-04-14 1978-11-10 Dow Chemical Co ELECTRODES COATING PROCESS
FR2433595A1 (en) * 1978-08-14 1980-03-14 Dow Chemical Co METHOD FOR COATING ELECTRODES WITH A RUTHENIUM DERIVATIVE
US4214971A (en) * 1978-08-14 1980-07-29 The Dow Chemical Company Electrode coating process
US4331528A (en) * 1980-10-06 1982-05-25 Diamond Shamrock Corporation Coated metal electrode with improved barrier layer
US4871703A (en) * 1983-05-31 1989-10-03 The Dow Chemical Company Process for preparation of an electrocatalyst
US4615913A (en) * 1984-03-13 1986-10-07 Kaman Sciences Corporation Multilayered chromium oxide bonded, hardened and densified coatings and method of making same
US4585540A (en) * 1984-09-13 1986-04-29 Eltech Systems Corporation Composite catalytic material particularly for electrolysis electrodes and method of manufacture
US6000982A (en) * 1995-07-31 1999-12-14 Casio Computer Co., Ltd. Method of manufacturing a cold-cathode for a discharge device
US6323549B1 (en) 1996-08-29 2001-11-27 L. Pierre deRochemont Ceramic composite wiring structures for semiconductor devices and method of manufacture
US5707715A (en) * 1996-08-29 1998-01-13 L. Pierre deRochemont Metal ceramic composites with improved interfacial properties and methods to make such composites
US20040194305A1 (en) * 1996-08-29 2004-10-07 L. Pierre Derochemont D/B/A C2 Technologies Method of manufacture of ceramic composite wiring structures for semiconductor devices
US7047637B2 (en) 1996-08-29 2006-05-23 Derochemont L Pierre Method of manufacture of ceramic composite wiring structures for semiconductor devices
US20060200958A1 (en) * 1996-08-29 2006-09-14 L. Pierre Derochemont D/B/A C2 Technologies Method of manufacture of ceramic composite wiring structures for semiconductor devices
US6143432A (en) * 1998-01-09 2000-11-07 L. Pierre deRochemont Ceramic composites with improved interfacial properties and methods to make such composites
US20040031692A1 (en) * 1999-06-28 2004-02-19 Kenneth Hardee Coatings for the inhibition of undesirable oxidation in an electrochemical cell
US7247229B2 (en) 1999-06-28 2007-07-24 Eltech Systems Corporation Coatings for the inhibition of undesirable oxidation in an electrochemical cell
US20030085199A1 (en) * 2001-11-08 2003-05-08 Korea Atomic Energy Research Institute & Technology Winners Co., Ltd. Method for manufacturing catalytic oxide anode using high temperature sintering
US20090288958A1 (en) * 2008-05-24 2009-11-26 Phelps Dodge Corporation Electrochemically active composition, methods of making, and uses thereof
US20090288856A1 (en) * 2008-05-24 2009-11-26 Phelps Dodge Corporation Multi-coated electrode and method of making
US8022004B2 (en) 2008-05-24 2011-09-20 Freeport-Mcmoran Corporation Multi-coated electrode and method of making
US8124556B2 (en) 2008-05-24 2012-02-28 Freeport-Mcmoran Corporation Electrochemically active composition, methods of making, and uses thereof
US8580091B2 (en) 2010-10-08 2013-11-12 Water Star, Inc. Multi-layer mixed metal oxide electrode and method for making same
US20130228450A1 (en) * 2010-12-22 2013-09-05 Industrie De Nora S.P.A. Electrode for electrolytic cell
CN104005047A (en) * 2014-06-11 2014-08-27 中国船舶重工集团公司第七二五研究所 Novel mixed metal oxide electrode for low-temperature sea water electrolysis antifouling
CN106099047A (en) * 2016-08-25 2016-11-09 深圳市贝特瑞纳米科技有限公司 A kind of surface coating method of electrode material and application thereof
US11668017B2 (en) 2018-07-30 2023-06-06 Water Star, Inc. Current reversal tolerant multilayer material, method of making the same, use as an electrode, and use in electrochemical processes

Also Published As

Publication number Publication date
ES400915A1 (en) 1975-01-16
NL7203580A (en) 1972-09-20
IL38958A0 (en) 1972-05-30
CA976505A (en) 1975-10-21
AR194834A1 (en) 1973-08-24
CH578625A5 (en) 1976-08-13
JPS559471B1 (en) 1980-03-10
FR2130419A1 (en) 1972-11-03
NO140235C (en) 1984-02-14
TR17134A (en) 1974-04-25
MY7400318A (en) 1974-12-31
FR2130419B1 (en) 1974-08-02
JPS4733076A (en) 1972-11-16
ZA721481B (en) 1972-11-29
AU463572B2 (en) 1975-07-14
NO140235B (en) 1979-04-17
DE2213083A1 (en) 1972-09-21
BR7201555D0 (en) 1973-06-14
AT312633B (en) 1974-01-10
GB1352872A (en) 1974-05-15
BE780756A (en) 1972-09-18
DD99934A5 (en) 1973-09-05
IT950343B (en) 1973-06-20
IL38958A (en) 1974-12-31
AU3985372A (en) 1973-09-13

Similar Documents

Publication Publication Date Title
US3869312A (en) Electrodes and electrochemical processes
US3882002A (en) Anode for electrolytic processes
US3663280A (en) Electrodes for electrochemical processes
US3773554A (en) Electrodes for electrochemical processes
US3773555A (en) Method of making an electrode
US3701724A (en) Electrodes for electrochemical processes
US3875043A (en) Electrodes with multicomponent coatings
US3948751A (en) Valve metal electrode with valve metal oxide semi-conductive face
US4070504A (en) Method of producing a valve metal electrode with valve metal oxide semi-conductor face and methods of manufacture and use
CA1060383A (en) Anode for electrolytic processes
US3853739A (en) Platinum group metal oxide coated electrodes
US4243503A (en) Method and electrode with admixed fillers
US3776834A (en) Partial replacement of ruthenium with tin in electrode coatings
US3986942A (en) Electrolytic process and apparatus
GB1562720A (en) Manganese dioxide electrodes
US3926751A (en) Method of electrowinning metals
EP0004387B1 (en) Electrodes for electrolytic processes
US3627669A (en) Electrodes for electrochemical cells
US4318795A (en) Valve metal electrode with valve metal oxide semi-conductor face and methods of carrying out electrolysis reactions
US3940323A (en) Anode for electrolytic processes
US6231731B1 (en) Electrolyzing electrode and process for the production thereof
FI56981C (en) ELECTROCHEMICAL PROCESSER AND FOUNDATION FOER DESS FRAMSTAELLNING
US3929608A (en) Catalytic material for electrodes
US4234405A (en) Electrode for electrochemical processes
US4049532A (en) Electrodes for electrochemical processes