EP0437178A1 - Electrode with electrocatalytic coating - Google Patents
Electrode with electrocatalytic coating Download PDFInfo
- Publication number
- EP0437178A1 EP0437178A1 EP90810945A EP90810945A EP0437178A1 EP 0437178 A1 EP0437178 A1 EP 0437178A1 EP 90810945 A EP90810945 A EP 90810945A EP 90810945 A EP90810945 A EP 90810945A EP 0437178 A1 EP0437178 A1 EP 0437178A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- coating
- mole percent
- oxide
- electrode
- titanium
- 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.)
- Granted
Links
- 238000000576 coating method Methods 0.000 title claims abstract description 60
- 239000011248 coating agent Substances 0.000 title claims abstract description 57
- 229910052751 metal Inorganic materials 0.000 claims abstract description 35
- 239000002184 metal Substances 0.000 claims abstract description 35
- 239000000758 substrate Substances 0.000 claims abstract description 33
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 28
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 26
- 239000010936 titanium Substances 0.000 claims abstract description 26
- 229910052741 iridium Inorganic materials 0.000 claims abstract description 18
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 claims abstract description 18
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910052707 ruthenium Inorganic materials 0.000 claims abstract description 17
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000001301 oxygen Substances 0.000 claims abstract description 8
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 8
- 239000012528 membrane Substances 0.000 claims abstract description 5
- 239000000243 solution Substances 0.000 claims description 31
- 239000008199 coating composition Substances 0.000 claims description 23
- 239000000203 mixture Substances 0.000 claims description 23
- 239000000470 constituent Substances 0.000 claims description 19
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 13
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 13
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims description 13
- HTXDPTMKBJXEOW-UHFFFAOYSA-N dioxoiridium Chemical compound O=[Ir]=O HTXDPTMKBJXEOW-UHFFFAOYSA-N 0.000 claims description 12
- 229910000457 iridium oxide Inorganic materials 0.000 claims description 12
- 229910001925 ruthenium oxide Inorganic materials 0.000 claims description 12
- WOCIAKWEIIZHES-UHFFFAOYSA-N ruthenium(iv) oxide Chemical compound O=[Ru]=O WOCIAKWEIIZHES-UHFFFAOYSA-N 0.000 claims description 12
- 238000005868 electrolysis reaction Methods 0.000 claims description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 238000005530 etching Methods 0.000 claims description 7
- 239000007921 spray Substances 0.000 claims description 7
- 239000003513 alkali Substances 0.000 claims description 5
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- 238000000137 annealing Methods 0.000 claims description 4
- 239000012736 aqueous medium Substances 0.000 claims description 4
- 229910052736 halogen Inorganic materials 0.000 claims description 4
- 150000002367 halogens Chemical class 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 claims description 4
- 150000007522 mineralic acids Chemical class 0.000 claims description 4
- 229910052726 zirconium Inorganic materials 0.000 claims description 4
- 239000012267 brine Substances 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 229910003455 mixed metal oxide Inorganic materials 0.000 claims description 3
- 229910052758 niobium Inorganic materials 0.000 claims description 3
- 239000010955 niobium Substances 0.000 claims description 3
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims description 3
- HPALAKNZSZLMCH-UHFFFAOYSA-M sodium;chloride;hydrate Chemical compound O.[Na+].[Cl-] HPALAKNZSZLMCH-UHFFFAOYSA-M 0.000 claims description 3
- 229910052715 tantalum Inorganic materials 0.000 claims description 3
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims description 3
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 3
- 229910052721 tungsten Inorganic materials 0.000 claims description 3
- 239000010937 tungsten Substances 0.000 claims description 3
- 150000003842 bromide salts Chemical class 0.000 claims description 2
- 150000004694 iodide salts Chemical class 0.000 claims description 2
- 230000002378 acidificating effect Effects 0.000 claims 2
- 229910045601 alloy Inorganic materials 0.000 claims 2
- 239000000956 alloy Substances 0.000 claims 2
- 239000003795 chemical substances by application Substances 0.000 claims 2
- 150000001805 chlorine compounds Chemical class 0.000 claims 2
- 239000003518 caustics Substances 0.000 abstract description 6
- 230000004580 weight loss Effects 0.000 abstract description 6
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 abstract description 5
- 239000000460 chlorine Substances 0.000 abstract description 5
- 229910052801 chlorine Inorganic materials 0.000 abstract description 5
- 239000002243 precursor Substances 0.000 description 10
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 5
- 150000002739 metals Chemical class 0.000 description 5
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 150000004706 metal oxides Chemical class 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- -1 sodium chloride Chemical class 0.000 description 3
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- 229910021638 Iridium(III) chloride Inorganic materials 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 229910000510 noble metal Inorganic materials 0.000 description 2
- 229910052763 palladium Inorganic materials 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Chemical compound [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- DANYXEHCMQHDNX-UHFFFAOYSA-K trichloroiridium Chemical compound Cl[Ir](Cl)Cl DANYXEHCMQHDNX-UHFFFAOYSA-K 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 229910001508 alkali metal halide Inorganic materials 0.000 description 1
- 150000008045 alkali metal halides Chemical class 0.000 description 1
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229940075397 calomel Drugs 0.000 description 1
- 150000003841 chloride salts Chemical class 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005238 degreasing Methods 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 230000002939 deleterious effect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 239000010432 diamond Substances 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- ZOMNIUBKTOKEHS-UHFFFAOYSA-L dimercury dichloride Chemical compound Cl[Hg][Hg]Cl ZOMNIUBKTOKEHS-UHFFFAOYSA-L 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- CJTCBBYSPFAVFL-UHFFFAOYSA-N iridium ruthenium Chemical compound [Ru].[Ir] CJTCBBYSPFAVFL-UHFFFAOYSA-N 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052762 osmium Inorganic materials 0.000 description 1
- SYQBFIAQOQZEGI-UHFFFAOYSA-N osmium atom Chemical compound [Os] SYQBFIAQOQZEGI-UHFFFAOYSA-N 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 1
- 235000011007 phosphoric acid Nutrition 0.000 description 1
- 150000003016 phosphoric acids Chemical class 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 235000010333 potassium nitrate Nutrition 0.000 description 1
- 239000004323 potassium nitrate Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- 239000010948 rhodium Substances 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- YBCAZPLXEGKKFM-UHFFFAOYSA-K ruthenium(iii) chloride Chemical compound [Cl-].[Cl-].[Cl-].[Ru+3] YBCAZPLXEGKKFM-UHFFFAOYSA-K 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- XJDNKRIXUMDJCW-UHFFFAOYSA-J titanium tetrachloride Chemical compound Cl[Ti](Cl)(Cl)Cl XJDNKRIXUMDJCW-UHFFFAOYSA-J 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
- 238000011179 visual inspection Methods 0.000 description 1
- 229910001928 zirconium oxide Inorganic materials 0.000 description 1
Classifications
-
- 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
- C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
- C25B11/051—Electrodes formed of electrocatalysts on a substrate or carrier
- C25B11/073—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material
- C25B11/091—Electrodes 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
- C25B11/093—Electrodes 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
-
- 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
- C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
- C25B11/051—Electrodes formed of electrocatalysts on a substrate or carrier
- C25B11/073—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material
- C25B11/091—Electrodes 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
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/18—After-treatment
-
- 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
- C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
- C25B11/051—Electrodes formed of electrocatalysts on a substrate or carrier
- C25B11/052—Electrodes comprising one or more electrocatalytic coatings on a substrate
- C25B11/053—Electrodes comprising one or more electrocatalytic coatings on a substrate characterised by multilayer electrocatalytic coatings
Definitions
- Electrodes for use in electrolytic processes have been known which have a base or core metal bearing a layer or coating of metal oxides.
- the core metal of the electrode may be a valve metal such as titanium, tantalum, zirconium, niobium or tungsten.
- the coating is an oxide mixture
- an oxide of the core or substrate metal can contribute to the mixture.
- such mixture can include an oxide of the substrate metal plus at least one oxide of a metal such as platinum, iridium, rhodium, palladium, ruthenium, and osmium.
- such mixture which can be termed a noble metal oxide mixture
- Such have been taught generally in U.S. Patent 3,632,498 and examples shown specifically, when combined with titanium oxide, in U.S. Patent 3,948,751.
- an aqueous alkali-metal halide e.g., sodium chloride
- it has been taught in U.S. Patent 4,005,004 that such noble metal oxide mixture can be particularly serviceable when in further mixture with both titanium oxide and zirconium oxide.
- Such a mixture yields a solid solution coating that ostensibly enhances the practical utilization of the electrodes for their intended use.
- the invention is broadly directed to an electrode having reduced oxygen evolution during electrolysis of halogen-containing solutions particularly at low pH, such electrode comprising an electrically conductive metal substrate having a coating of enhanced stability under alkaline conditions, which coating comprises at least 15, but less than 25, mole percent iridium oxide, 35-50 mole percent ruthenium oxide and at least 30, but less than 45 mole percent titanium oxide basis 100 mole percent of the oxides present in the coating.
- the coating has a molar ratio of titanium oxide to the total of the oxides of iridium and ruthenium of less than 1: 1, and should have a molar ratio of ruthenium oxide to iridium oxide of greater than 1.5: 1 and up to 3: 1.
- the invention is directed to a coating composition adapted for providing the foregoing described mixed metal oxide coating and in a still further aspect is directed to the method of making an electrode which is hereinbefore defined.
- the electrode will be particularly useful as an anode in a membrane cell used for the electrolysis of brine that is at a pH within the range of from about 2 to about 4.
- the coating composition of the present invention is broadly applicable to any electrically conductive metal substrate which will be sufficiently electrically conductive to serve as an electrode in an electrolysis process.
- the metals of the substrate are broadly contemplated, but in view of the application of an electrocatalytic coating, the substrate metals more typically may be such as nickel or manganese, or most always the valve metals, including titanium, tantalum, aluminum, tungsten, zirconium and niobium. Of particular interest for its ruggedness, corrosion resistance and availability is titanium.
- the suitable metals of the substrate can include metal alloys and intermetallic mixtures.
- titanium may generally be alloyed with nickel, cobalt, iron, manganese or copper.
- Grade 5 titanium may include up to 6.75 weight % aluminum and 4.5 weight % vanadium, grade 6 up to 6% aluminum and 3% tin, grade 7 up to 0.25 weight % palladium, grade 10, from 10 to 13 weight % molybdenum plus 4.5 to 7.5 weight % zirconium and so on.
- the coating composition applied to the coated metal substrate will be aqueous, which will most always be simply water without any blending with further liquid.
- aqueous compositions that are serviceable will be solutions of precursor constituents in the aqueous medium, that is, precursors to the oxides that will be present in the coating.
- the precursor constituents utilized in the aqueous solution are those which can be solubilized in water efficiently and economically, e.g., achieve solution without extensive boiling condition.
- the precursors must supply the respective metal oxide on thermodecomposition. Where they are all present in the same composition, they must also be compatible with one another.
- each precursor constituent will be a metal salt that most often is a halide salt and preferably for economy coupled with efficiency of solution preparation such will all be the chloride salt.
- other useful salts include iodides, bromides and ammonium chloro salts such as ammonium hexachloro iridate or ruthenate.
- a solution of iridium trichloride can further contain strong acid, most always hydrochloric acid, which will usually be present in an amount to supply about 5 to 20 weight percent acid.
- the individual or combination solutions will have a pH of less than 1, such as within the range of from about 0.2 to about 0.8.
- the coating composition is a solution of all precursor constituents, such will contain at least 15, but less than 25, mole percent of the iridium constituent, 35-50 mole percent of the ruthenium constituent, and at least 30, but less than 45, mole percent of the titanium constituent, basis 100 mole percent of these constituents.
- a composition containing an iridium constituent in an amount of less than 15 mole percent will be inadequate for providing an electrode coating having the best caustic stability, such as when the electrode is used in a chlor-alkali cell.
- less than 25 mole percent for the iridium precursor will be desirable for best low operating potential efficiency for the coating.
- the ruthenium In regard to the ruthenium, a constituent amount in the solution of less than about 35 mole percent will be insufficient to provide the most efficient low chlorine potential for resulting coatings, while an amount not greater than 50 mole percent enhances coating stability. Also, for best coating characteristics, the molar ratio of ruthenium oxide to iridium oxide in the resulting coating will be from greater than 1.5: 1 up to 3: 1.
- the coating solution will contain constituents in a proportion such as to provide from about 18-22 mole percent iridium, 35-40 mole percent ruthenium, and 40-44 mole percent titanium.
- the resulting coating will furthermore have a molar ratio of titanium oxide to the total of the oxides of iridium ruthenium of less than 1: 1, but most always above 0.5: 1.
- the substrate metal Before applying the coating composition to the substrate metal, the substrate metal advantageously is a cleaned surface. This may be obtained by any of the treatments used to achieve a clean metal surface, including mechanical cleaning. The usual cleaning procedures of degreasing, either chemical or electrolytic, or other chemical cleaning operation may also be used to advantage.
- the substrate preparation includes annealing, and the metal is grade 1 titanium
- the titanium can be annealed at a temperature of at least about 450°C. for a time of at least about 15 minutes, but most often a more elevated annealing temperature, e.g., 600°-875°C. is advantageous.
- etching it will be with an active etch solution.
- Typical etch solutions are acid solutions. These can be provided by hydrochloric, sulfuric, perchloric, nitric, oxalic, tartaric, and phosphoric acids as well as mixtures thereof, e.g., aqua regia.
- Other etchants that may be utilized include caustic etchants such as a solution of potassium hydroxide/hydrogen peroxide in combination, or a melt of potassium hydroxide with potassium nitrate.
- the etch solution is advantageously a strong, or concentrated, aqueous solution, such as an 18-22 weight % solution of hydrochloric acid, or a solution of sulfuric acid.
- the solution is advantageously maintained during etching at elevated temperature such as at 80°C. or more for aqueous solutions, and often at or near boiling condition or greater, e.g., under refluxing condition.
- the etching will prepare a roughened surface, as determined by aided, visual inspection. Following etching, the etched metal surface can then be subjected to rinsing and drying steps to prepare the surface for coating.
- the coating composition can then be applied to the metal substrate by any means for typically applying an aqueous coating composition to a substrate metal.
- Such methods of application include brush, roller, and spray application.
- combination techniques can be utilized, e.g., spray and brush technique.
- Spray application can be either conventional compressed gas or can be electrostatic spray application.
- electrostatic spray application will be used for best wrap around affect of the spray for coating the back side of an article such as a mesh electrode.
- the applied composition will be heated to prepare the resulting mixed oxide coating by thermodecomposition of the precursors present in the coating composition.
- This prepares the mixed oxide coating containing the mixed oxides in the molar proportions as above discussed.
- Such heating for the thermodecomposition will be conducted at a temperature of at least about 440°C. peak metal temperature for a time of at least about 3 minutes. More typically the applied coating will be heated at a more elevated temperature for a slightly longer time, but usually a temperature of greater than about 550°C. is avoided for economy and to avoid detrimental effects on anode potential where the coated metal will serve as an anode. Suitable conditions can include heating in air or oxygen.
- the heated and coated substrate will usually be permitted to cool to at least substantially ambient temperature.
- the resulting finished coating has a smooth appearance to the unaided eye, but under microscopic examination is seen to be non-homogeneous, having embedded crystallites in the field of the coating.
- a coating solution was prepared by combining 157 gms of iridium, using a solution of iridium trichloride in 18% by weight HCl, 144 gms of ruthenium, using a solution of ruthenium trichloride in 18% by weight HCl, 80 gms of titanium, using titanium tetrachloride in 10% by weight HCl solution, 331 gms HCl, using 36 weight % solution, then diluting to 10 liters with deionized water.
- This provided a coating composition having 21 mole % iridium; 36.3 mole % ruthenium, and 42.7 mole % titanium.
- Four liters of 93 grams per liter (gpl) HCl solution were then added to make the final coating solution.
- This solution was applied using a hand roller to a titanium mesh substrate having a diamond-patterned mesh, with each diamond pattern having about 8 millimeters (mms.) long way of design plus about 4 mms. short way of design.
- the titanium mesh had been annealed at 600°C. for 30 minutes and etched in 25 wt % sulfuric acid at 85-90°C., then water rinsed and air dried. The applied coating was air dried then baked at 470°C. Eighteen (18) coats were applied in this manner. After the final coat, the anode was postbaked at 525°C. for 4 hours.
- the average caustic weight loss of 5.27 gm/m2 was especially noteworthy since a comparative coating having 7.8 mole percent iridium oxide, 15 mole percent ruthenium oxide and 77.2 mole percent titanium oxide exhibited such weight loss of 8.9 gm/m2 when tested under the same conditions. Moreover, again comparatively, but as the mole percent changed to more closely approach the invention composition, but still in a comparative coating, the caustic weight loss increased to 19.2 gm/m2
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Abstract
Description
- Electrodes for use in electrolytic processes have been known which have a base or core metal bearing a layer or coating of metal oxides. The core metal of the electrode may be a valve metal such as titanium, tantalum, zirconium, niobium or tungsten. Where the coating is an oxide mixture, an oxide of the core or substrate metal can contribute to the mixture. As taught for example in U.S. Patent 3,711,385, such mixture can include an oxide of the substrate metal plus at least one oxide of a metal such as platinum, iridium, rhodium, palladium, ruthenium, and osmium.
- It has also been known that such mixture which can be termed a noble metal oxide mixture, can be a mixture of ruthenium oxide and iridium oxide. Such have been taught generally in U.S. Patent 3,632,498 and examples shown specifically, when combined with titanium oxide, in U.S. Patent 3,948,751. Particularly for utilization as a coating on an electrode used in an electrolysis of an aqueous alkali-metal halide, e.g., sodium chloride, it has been taught in U.S. Patent 4,005,004 that such noble metal oxide mixture can be particularly serviceable when in further mixture with both titanium oxide and zirconium oxide. Such a mixture, as taught in the patent, yields a solid solution coating that ostensibly enhances the practical utilization of the electrodes for their intended use.
- More recently, it has been proposed for enhanced wear resistance of an electrode, especially when utlized in electrolysis producing oxygen and chlorine in combination, to provide the molar amount of titanium oxide equal to or greater than the moles of the total oxides of iridium and ruthenium. Such has been disclosed in U.S. Patent 4,564,434, wherein there is also taught providing the molar amount of iridium oxide about the same as, to greater than, the molar amount of ruthenium oxide.
- It would however be desirable to provide an electrocatalytic coating which in electrolysis of halogen-containing solutions, e.g., chlor-alkali production from brine electrolysis, will achieve reduced oxygen evolution. It would also be particularly desirable to provide such a coating exhibiting retarded weight loss when exposed to caustic. It would be most beneficial if such characteristics could be achieved, not only in combination, but without sacrifice to other wanted features, e.g., no sacrifice in the chlorine evolution potential for the anode. It would also be advantageous to prepare an electrode using a coating composition that is readily prepared, has a simplistic formulation, and provides ease and safety in handling and use.
- The invention is broadly directed to an electrode having reduced oxygen evolution during electrolysis of halogen-containing solutions particularly at low pH, such electrode comprising an electrically conductive metal substrate having a coating of enhanced stability under alkaline conditions, which coating comprises at least 15, but less than 25, mole percent iridium oxide, 35-50 mole percent ruthenium oxide and at least 30, but less than 45 mole percent titanium oxide basis 100 mole percent of the oxides present in the coating. Thereby the coating has a molar ratio of titanium oxide to the total of the oxides of iridium and ruthenium of less than 1: 1, and should have a molar ratio of ruthenium oxide to iridium oxide of greater than 1.5: 1 and up to 3: 1.
- In another aspect, the invention is directed to a coating composition adapted for providing the foregoing described mixed metal oxide coating and in a still further aspect is directed to the method of making an electrode which is hereinbefore defined. The electrode will be particularly useful as an anode in a membrane cell used for the electrolysis of brine that is at a pH within the range of from about 2 to about 4.
- The coating composition of the present invention is broadly applicable to any electrically conductive metal substrate which will be sufficiently electrically conductive to serve as an electrode in an electrolysis process. Thus the metals of the substrate are broadly contemplated, but in view of the application of an electrocatalytic coating, the substrate metals more typically may be such as nickel or manganese, or most always the valve metals, including titanium, tantalum, aluminum, tungsten, zirconium and niobium. Of particular interest for its ruggedness, corrosion resistance and availability is titanium. As well as the normally available elemental metals themselves, the suitable metals of the substrate can include metal alloys and intermetallic mixtures. For example, titanium may generally be alloyed with nickel, cobalt, iron, manganese or copper. More specifically, Grade 5 titanium may include up to 6.75 weight % aluminum and 4.5 weight % vanadium, grade 6 up to 6% aluminum and 3% tin, grade 7 up to 0.25 weight % palladium, grade 10, from 10 to 13 weight % molybdenum plus 4.5 to 7.5 weight % zirconium and so on.
- The coating composition applied to the coated metal substrate will be aqueous, which will most always be simply water without any blending with further liquid. Preferably, deionized or distilled water is used to avoid inorganic impurities. For economy of preparation and utilization, the aqueous compositions that are serviceable will be solutions of precursor constituents in the aqueous medium, that is, precursors to the oxides that will be present in the coating. The precursor constituents utilized in the aqueous solution are those which can be solubilized in water efficiently and economically, e.g., achieve solution without extensive boiling condition. Moreover, the precursors must supply the respective metal oxide on thermodecomposition. Where they are all present in the same composition, they must also be compatible with one another. In this regard, they are advantageously non-reactive toward one another, e.g., will not react so as to form products which will lead to deleterious non-oxide substituents in the coating or precipitate from the coming solution. Usually, each precursor constituent will be a metal salt that most often is a halide salt and preferably for economy coupled with efficiency of solution preparation such will all be the chloride salt. However, other useful salts include iodides, bromides and ammonium chloro salts such as ammonium hexachloro iridate or ruthenate.
- In the individual or combination solutions, in addition to the suitable precursor constituent, most always with only one exception no further solution ingredients will be present. Such exception will virtually always be the presence of inorganic acid. For example, a solution of iridium trichloride can further contain strong acid, most always hydrochloric acid, which will usually be present in an amount to supply about 5 to 20 weight percent acid. Typically, the individual or combination solutions will have a pH of less than 1, such as within the range of from about 0.2 to about 0.8.
- When the coating composition is a solution of all precursor constituents, such will contain at least 15, but less than 25, mole percent of the iridium constituent, 35-50 mole percent of the ruthenium constituent, and at least 30, but less than 45, mole percent of the titanium constituent, basis 100 mole percent of these constituents. A composition containing an iridium constituent in an amount of less than 15 mole percent will be inadequate for providing an electrode coating having the best caustic stability, such as when the electrode is used in a chlor-alkali cell. On the other hand, less than 25 mole percent for the iridium precursor will be desirable for best low operating potential efficiency for the coating. In regard to the ruthenium, a constituent amount in the solution of less than about 35 mole percent will be insufficient to provide the most efficient low chlorine potential for resulting coatings, while an amount not greater than 50 mole percent enhances coating stability. Also, for best coating characteristics, the molar ratio of ruthenium oxide to iridium oxide in the resulting coating will be from greater than 1.5: 1 up to 3: 1.
- For the titanium precursor in the coating composition, an amount providing less than 30 mole percent titanium is uneconomical while 45 mole percent titanium or more can lead to higher operating potential for electrode coatings operating in chlor-alkali cells. Preferably for best economy, coupled with the overall most desirable coating characteristics, the coating solution will contain constituents in a proportion such as to provide from about 18-22 mole percent iridium, 35-40 mole percent ruthenium, and 40-44 mole percent titanium. The resulting coating will furthermore have a molar ratio of titanium oxide to the total of the oxides of iridium ruthenium of less than 1: 1, but most always above 0.5: 1.
- Before applying the coating composition to the substrate metal, the substrate metal advantageously is a cleaned surface. This may be obtained by any of the treatments used to achieve a clean metal surface, including mechanical cleaning. The usual cleaning procedures of degreasing, either chemical or electrolytic, or other chemical cleaning operation may also be used to advantage. Where the substrate preparation includes annealing, and the metal is grade 1 titanium, the titanium can be annealed at a temperature of at least about 450°C. for a time of at least about 15 minutes, but most often a more elevated annealing temperature, e.g., 600°-875°C. is advantageous.
- After the foregoing operation, e.g., cleaning, or cleaning and annealing, and including any desirable rinsing and drying steps, the metal surface is then ready for continuing operation. Where such is etching, it will be with an active etch solution. Typical etch solutions are acid solutions. These can be provided by hydrochloric, sulfuric, perchloric, nitric, oxalic, tartaric, and phosphoric acids as well as mixtures thereof, e.g., aqua regia. Other etchants that may be utilized include caustic etchants such as a solution of potassium hydroxide/hydrogen peroxide in combination, or a melt of potassium hydroxide with potassium nitrate. For efficiency of operation, the etch solution is advantageously a strong, or concentrated, aqueous solution, such as an 18-22 weight % solution of hydrochloric acid, or a solution of sulfuric acid. Moreover, the solution is advantageously maintained during etching at elevated temperature such as at 80°C. or more for aqueous solutions, and often at or near boiling condition or greater, e.g., under refluxing condition. Preferably, the etching will prepare a roughened surface, as determined by aided, visual inspection. Following etching, the etched metal surface can then be subjected to rinsing and drying steps to prepare the surface for coating.
- The coating composition can then be applied to the metal substrate by any means for typically applying an aqueous coating composition to a substrate metal. Such methods of application include brush, roller, and spray application. Moreover, combination techniques can be utilized, e.g., spray and brush technique. Spray application can be either conventional compressed gas or can be electrostatic spray application. Advantageously, electrostatic spray application will be used for best wrap around affect of the spray for coating the back side of an article such as a mesh electrode.
- Following application of the coating, the applied composition will be heated to prepare the resulting mixed oxide coating by thermodecomposition of the precursors present in the coating composition. This prepares the mixed oxide coating containing the mixed oxides in the molar proportions as above discussed. Such heating for the thermodecomposition will be conducted at a temperature of at least about 440°C. peak metal temperature for a time of at least about 3 minutes. More typically the applied coating will be heated at a more elevated temperature for a slightly longer time, but usually a temperature of greater than about 550°C. is avoided for economy and to avoid detrimental effects on anode potential where the coated metal will serve as an anode. Suitable conditions can include heating in air or oxygen. Following such heating, and before additional coating as where an additional application of the coating composition will be applied, the heated and coated substrate will usually be permitted to cool to at least substantially ambient temperature. The resulting finished coating has a smooth appearance to the unaided eye, but under microscopic examination is seen to be non-homogeneous, having embedded crystallites in the field of the coating. Although the application of coating compositions other than as disclosed herein is then contemplated, for best overall performance of the coated substrate metal as an electrode, subsequently applied coatings will be of those compositions of the invention disclosed herein.
- The following example shows a way in which the invention has been practiced, but should not be construed as limiting the invention.
- A coating solution was prepared by combining 157 gms of iridium, using a solution of iridium trichloride in 18% by weight HCl, 144 gms of ruthenium, using a solution of ruthenium trichloride in 18% by weight HCl, 80 gms of titanium, using titanium tetrachloride in 10% by weight HCl solution, 331 gms HCl, using 36 weight % solution, then diluting to 10 liters with deionized water. This provided a coating composition having 21 mole % iridium; 36.3 mole % ruthenium, and 42.7 mole % titanium. Four liters of 93 grams per liter (gpl) HCl solution were then added to make the final coating solution.
- This solution was applied using a hand roller to a titanium mesh substrate having a diamond-patterned mesh, with each diamond pattern having about 8 millimeters (mms.) long way of design plus about 4 mms. short way of design. The titanium mesh had been annealed at 600°C. for 30 minutes and etched in 25 wt % sulfuric acid at 85-90°C., then water rinsed and air dried. The applied coating was air dried then baked at 470°C. Eighteen (18) coats were applied in this manner. After the final coat, the anode was postbaked at 525°C. for 4 hours.
- Operation of eight samples of the resulting coated titanium substrate, when utilized as an anode in 12 normal NaOH at 95°C. for 4 hours at 25 kA/m² resulted in an average weight loss of 5.27 gm/m². Use of a sample as an anode in a chlor-alkali membrane cell operating at 3.3 kA/m² resulted in 0.06%, 0.22%, and 0.38%, by volume, oxygen produced in the chlorine cell product at an electrolyte pH of 2, 3 and 4, respectively. The operating potential of this anode in the membrane cell was 1.09 volts vs. a standard calomel reference electrode.
- The average caustic weight loss of 5.27 gm/m² was especially noteworthy since a comparative coating having 7.8 mole percent iridium oxide, 15 mole percent ruthenium oxide and 77.2 mole percent titanium oxide exhibited such weight loss of 8.9 gm/m² when tested under the same conditions. Moreover, again comparatively, but as the mole percent changed to more closely approach the invention composition, but still in a comparative coating, the caustic weight loss increased to 19.2 gm/m²
Claims (21)
- An electrode having reduced oxygen evolution during electrolysis of halogen-containing solutions at low pH, said electrode comprising an electrically conductive metal substrate having a coating of enhanced stability under alkaline conditions, which coating comprises at least 15, but less than 25, mole percent iridium oxide, 35-50 mole percent ruthenium oxide and at least 30, but less than 45, mole percent titanium oxide, basis 100 mole percent of these oxides present in the coating, whereby the coating has a molar ratio of titanium oxide to the total of the oxides of iridium and ruthenium of less than 1: 1, with the molar ratio of ruthenium oxide to iridium oxide being from greater than 1.5: 1 and up to 3: 1.
- The electrode of claim 1, wherein said conductive metal substrate comprises a metal selected from titanium, tantalum, zirconium, niobium, aluminum, tungsten and alloys and intermetallic mixtures thereof.
- The electrode of claim 1, wherein said conductive metal substrate comprises titanium, or an alloy or intermetallic mixture containing titanium.
- The electrode of claim 3, wherein said conductive metal substrate comprises an annealed and etched titanium substrate.
- The electrode of claim 1, wherein said coating is a non-homogeneous but smooth coating of mixed oxides and consists essentially of 18-22 mole percent iridium oxide, 35-40 mole percent ruthenium oxide and 40-44 mole percent titanium oxide, with a molar ratio of ruthenium oxide to iridium oxide of from 1.7: 1 to 2.2: 1.
- The electrode of claim 1, wherein said electrode is an anode in a membrane cell used for the electrolysis of brine that is at a pH within the range of from about 2 to about 4.
- A coating composition adapted for providing a mixed metal oxide coating on a metal substrate, which composition comprises an acidic aqueous medium containing soluble constituents of iridium, ruthenium and titanium in proportion providing at least 15, but less than 25, mole percent iridium, 35-50 mole percent ruthenium and at least 30, but less than 45, mole percent titanium, basis 100 mole percent of such constituents, whereby the composition has a molar ratio of titanium oxide to the total of the oxides of iridium and ruthenium of less than 1: 1, with the molar ratio of ruthenium to iridium being from greater than 1.5: 1 up to 3: 1.
- The coating composition of claim 7, wherein said acidic aqueous medium contains strong inorganic acid in water and is at a pH within the range of from about 0.2 to about 0.8.
- The coating composition of claim 8, wherein said strong inorganic acid is hydrochloric acid.
- The coating composition of claim 7, wherein said soluble constituents are compatible and are selected from chlorides, bromides, iodides and ammonium chloro salts.
- The coating composition of claim 10, wherein all said soluble constituents are chlorides and said aqueous medium contains hydrochloric acid.
- The coating composition of claim 7, wherein said proportions provide 18-22 mole percent iridium, 35-40 mole percent ruthenium and 40-44 mole percent titanium, basis 100 mole percent of these constituents, with a molar ratio of ruthenium to iridium being from 1.7: 1 to 2.2: 1.
- The coating composition of claim 7, wherein said composition provides an electrocatalytic coating of said mixed metal oxides on an electrically conductive valve metal substrate.
- The method of making an electrode having an electrocatalytic coating of enhanced performance in a chlor-alkali cell when said coating is present in said electrode on an electrically conductive metal substrate, which method comprises:annealing a titanium substrate at a temperature of at least about 450°C. for a time of at least about 0.25 hour;etching the resulting annealed surface with strong etching agent to produce a roughened surface;applying to the resulting etched surface an aqueous coating composition comprising constituents that are thermally decomposable to provide a mixed oxide coating of the constituents in the amount of at least 15, but less than 25 mole percent iridium oxide, 35-50 mole percent ruthenium oxide and at least 30, but less than 45, mole percent titanium oxide, basis 100 mole percent of these oxides present in the coating, whereby the coating has a molar ratio of titanium oxide to the total of the oxides of iridium and ruthenium of less than 1: 1, with the molar ratio of ruthenium oxide to iridium oxide being from greater than 1.5: 1 and up to 3: 1; andheating the resulting coated substrate at a temperature of at least about 440°C. for a time of at least about 3 minutes.
- The method of claim 14, wherein said annealed substrate is cooled to at least substantially about room temperature and the resulting cooled substrate is then etched.
- The method of claim 14, wherein said annealed substrate is etched with strong inorganic acid etching agent.
- The method of claim 14, wherein said etched surface is water rinsed prior to application of said coating composition.
- The method of claim 14, wherein said etched surface is a roughened, etched surface.
- The method of claim 14, wherein said coating composition is applied to said titanium substrate by electrostatic spray application.
- The method of claim 14, wherein said titanium substrate is annealed at a temperature within the range of from about 600°C. to about 875°C.
- An electrode having reduced oxygen evolution during electrolysis of halogen-containing solutions at low pH, while having a coating of enhanced stability under alkaline conditions, which electrode is produced by the method of claim 14.
Applications Claiming Priority (2)
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US44777589A | 1989-12-08 | 1989-12-08 | |
US447775 | 1989-12-08 |
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EP0437178A1 true EP0437178A1 (en) | 1991-07-17 |
EP0437178B1 EP0437178B1 (en) | 1995-09-13 |
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EP90810945A Expired - Lifetime EP0437178B1 (en) | 1989-12-08 | 1990-12-04 | Electrode with electrocatalytic coating |
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EP (1) | EP0437178B1 (en) |
JP (1) | JPH03188291A (en) |
KR (1) | KR910012344A (en) |
AR (1) | AR245508A1 (en) |
AT (1) | ATE127863T1 (en) |
AU (1) | AU640719B2 (en) |
BR (1) | BR9006109A (en) |
CA (1) | CA2030092C (en) |
DE (1) | DE69022386T2 (en) |
ES (1) | ES2076349T3 (en) |
NO (1) | NO302858B1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7566389B2 (en) | 2003-10-08 | 2009-07-28 | Akzo Nobel N.V. | Electrode |
EP2390385A1 (en) * | 2010-05-25 | 2011-11-30 | Permelec Electrode Ltd. | Anode for electrolysis and manufacturing method thereof |
DE102010023418A1 (en) * | 2010-06-11 | 2011-12-15 | Uhde Gmbh | Single or multi-sided substrate coating |
US20130186750A1 (en) * | 2010-11-26 | 2013-07-25 | Industrie De Nora S.P.A. | Anode for electrolytic evolution of chlorine |
US8617377B2 (en) | 2010-11-04 | 2013-12-31 | Permelec Electrode Ltd. | Method for a metal electrowinning |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100407710B1 (en) * | 2001-11-08 | 2003-12-01 | (주) 테크윈 | Catalytic oxide anode manufacturing method by high temperature sintering |
KR100898173B1 (en) * | 2008-07-09 | 2009-05-19 | 금강엔지니어링 주식회사 | Electrode manufacturing methode for treatment wastewater |
KR20160120377A (en) | 2015-04-07 | 2016-10-18 | 주식회사 마텍스코리아 | Electrode manufacturing method having a carbon nano-plane structure |
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EP0153586A1 (en) * | 1984-01-31 | 1985-09-04 | TDK Corporation | Electrode for electrolysis |
US4564434A (en) * | 1984-09-28 | 1986-01-14 | Busse Machukas Vladimir B | Electrode for electrolysis of solutions of electrolytes |
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US4457824A (en) * | 1982-06-28 | 1984-07-03 | General Electric Company | Method and device for evolution of oxygen with ternary electrocatalysts containing valve metals |
-
1990
- 1990-11-15 CA CA002030092A patent/CA2030092C/en not_active Expired - Fee Related
- 1990-11-28 JP JP2328816A patent/JPH03188291A/en active Pending
- 1990-11-28 AR AR90318490A patent/AR245508A1/en active
- 1990-11-30 BR BR909006109A patent/BR9006109A/en not_active IP Right Cessation
- 1990-12-04 ES ES90810945T patent/ES2076349T3/en not_active Expired - Lifetime
- 1990-12-04 AT AT90810945T patent/ATE127863T1/en not_active IP Right Cessation
- 1990-12-04 EP EP90810945A patent/EP0437178B1/en not_active Expired - Lifetime
- 1990-12-04 DE DE69022386T patent/DE69022386T2/en not_active Expired - Fee Related
- 1990-12-07 NO NO905305A patent/NO302858B1/en unknown
- 1990-12-07 AU AU67858/90A patent/AU640719B2/en not_active Ceased
- 1990-12-07 KR KR1019900020120A patent/KR910012344A/en not_active Application Discontinuation
Patent Citations (4)
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FR2189122A1 (en) * | 1972-06-23 | 1974-01-25 | Diamond Shamrock Corp | |
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 |
EP0153586A1 (en) * | 1984-01-31 | 1985-09-04 | TDK Corporation | Electrode for electrolysis |
US4564434A (en) * | 1984-09-28 | 1986-01-14 | Busse Machukas Vladimir B | Electrode for electrolysis of solutions of electrolytes |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7566389B2 (en) | 2003-10-08 | 2009-07-28 | Akzo Nobel N.V. | Electrode |
EP2390385A1 (en) * | 2010-05-25 | 2011-11-30 | Permelec Electrode Ltd. | Anode for electrolysis and manufacturing method thereof |
US8366889B2 (en) | 2010-05-25 | 2013-02-05 | Permelec Electrode Ltd. | Anode for electrolysis and manufacturing method thereof |
DE102010023418A1 (en) * | 2010-06-11 | 2011-12-15 | Uhde Gmbh | Single or multi-sided substrate coating |
US10030300B2 (en) | 2010-06-11 | 2018-07-24 | Thyssenkrupp Industrial Solutions Ag | Substrate coating on one or more sides |
US8617377B2 (en) | 2010-11-04 | 2013-12-31 | Permelec Electrode Ltd. | Method for a metal electrowinning |
EP2450475A3 (en) * | 2010-11-04 | 2016-01-27 | Permelec Electrode Ltd. | An anode for metal electrowinning |
US20130186750A1 (en) * | 2010-11-26 | 2013-07-25 | Industrie De Nora S.P.A. | Anode for electrolytic evolution of chlorine |
AU2011333664B2 (en) * | 2010-11-26 | 2016-10-27 | Industrie De Nora S.P.A. | Anode for electrolytic evolution of chlorine |
US11634827B2 (en) * | 2010-11-26 | 2023-04-25 | Industrie De Nora S.P.A. | Anode for electrolytic evolution of chlorine |
Also Published As
Publication number | Publication date |
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JPH03188291A (en) | 1991-08-16 |
DE69022386T2 (en) | 1996-03-07 |
AU6785890A (en) | 1991-06-13 |
BR9006109A (en) | 1991-09-24 |
CA2030092C (en) | 1998-11-03 |
DE69022386D1 (en) | 1995-10-19 |
NO905305D0 (en) | 1990-12-07 |
ATE127863T1 (en) | 1995-09-15 |
EP0437178B1 (en) | 1995-09-13 |
NO302858B1 (en) | 1998-05-04 |
NO905305L (en) | 1991-06-10 |
KR910012344A (en) | 1991-08-07 |
AR245508A1 (en) | 1994-01-31 |
AU640719B2 (en) | 1993-09-02 |
ES2076349T3 (en) | 1995-11-01 |
CA2030092A1 (en) | 1991-06-09 |
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