CA2815137C - Platinum-group-metal activated multi-layer electrode for electrolytic cell - Google Patents
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- CA2815137C CA2815137C CA2815137A CA2815137A CA2815137C CA 2815137 C CA2815137 C CA 2815137C CA 2815137 A CA2815137 A CA 2815137A CA 2815137 A CA2815137 A CA 2815137A CA 2815137 C CA2815137 C CA 2815137C
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- 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
- C25B11/042—Electrodes formed of a single material
- C25B11/046—Alloys
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- 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
- C25B11/055—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the substrate or carrier material
- C25B11/057—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the substrate or carrier material consisting of a single element or compound
- C25B11/061—Metal or alloy
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- 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
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- 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
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- 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
- C25B11/097—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 comprising two or more noble metals or noble metal alloys
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- Electrodes For Compound Or Non-Metal Manufacture (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
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Abstract
The invention relates to an electrode for evolution of gaseous products in electrolysis cells comprising a metal substrate coated with at least two catalytic compositions, the outermost catalytic composition being deposited by means of chemical or physical phase vapour deposition technique and having a composition comprising noble metals selected from the group of platinum group metals or oxides thereof.
Description
PLATINUM-GROUP-METAL ACTIVATED MULTI-LAYER ELECTRODE
FOR ELECTROLYTIC CELL
FIELD OF THE INVENTION
The invention relates to an electrode suitable for operating as anode in electrolysis cells, for instance as chlorine-evolving anode in chlor-alkali cells.
BACKGROUND OF THE INVENTION
The use of metal electrodes equipped with catalytic coatings in electrolytic applications is known in the art: electrodes consisting of a metal substrate equipped with a coating based on noble metals or oxides thereof are for instance utilised as cathodes for hydrogen evolution in water or alkali chloride electrolysis processes, as anodes for oxygen evolution in electrometallurgical processes of various kinds or for chlorine evolution in alkali chloride electrolysis. Electrodes of such kind can be produced via thermal route, i. e. by suitable thermal decomposition of solutions containing the precursors of metals to be deposited; by galvanic electrodeposition from suitable electrolytic baths; by direct metallisation via flame or plasma spraying processes or chemical or physical phase vapour deposition.
The electrolysis of sodium chloride brine directed to the production of chlorine and caustic soda, for instance, is often carried out with anodes consisting of a titanium or other valve metal substrate activated with a superficial layer or ruthenium dioxide (RU02) in order to lower the overvoltage of the anodic chorine evolution reaction. For this type of electrolysis, catalyst formulations based on mixtures of oxides of ruthenium, iridium and titanium are also known, all capable of lowering the overvoltage of the anodic chorine evolution reaction.
Electrodes of such kind are generally produced via thermal route.
Catalytic formulations can be deposited on the substrate by phase vapour deposition techniques, having the advantage of allowing an extremely accurate control of coating deposition parameters.
However, these are fundamentally characterised by being
FOR ELECTROLYTIC CELL
FIELD OF THE INVENTION
The invention relates to an electrode suitable for operating as anode in electrolysis cells, for instance as chlorine-evolving anode in chlor-alkali cells.
BACKGROUND OF THE INVENTION
The use of metal electrodes equipped with catalytic coatings in electrolytic applications is known in the art: electrodes consisting of a metal substrate equipped with a coating based on noble metals or oxides thereof are for instance utilised as cathodes for hydrogen evolution in water or alkali chloride electrolysis processes, as anodes for oxygen evolution in electrometallurgical processes of various kinds or for chlorine evolution in alkali chloride electrolysis. Electrodes of such kind can be produced via thermal route, i. e. by suitable thermal decomposition of solutions containing the precursors of metals to be deposited; by galvanic electrodeposition from suitable electrolytic baths; by direct metallisation via flame or plasma spraying processes or chemical or physical phase vapour deposition.
The electrolysis of sodium chloride brine directed to the production of chlorine and caustic soda, for instance, is often carried out with anodes consisting of a titanium or other valve metal substrate activated with a superficial layer or ruthenium dioxide (RU02) in order to lower the overvoltage of the anodic chorine evolution reaction. For this type of electrolysis, catalyst formulations based on mixtures of oxides of ruthenium, iridium and titanium are also known, all capable of lowering the overvoltage of the anodic chorine evolution reaction.
Electrodes of such kind are generally produced via thermal route.
Catalytic formulations can be deposited on the substrate by phase vapour deposition techniques, having the advantage of allowing an extremely accurate control of coating deposition parameters.
However, these are fundamentally characterised by being
2 batch-type processes, requiring the loading of the substrate in a suitable deposition chamber, which has to undergo a slow depressurisation process, lasting several hours, in order to be able to treat a single piece. Besides the remarkable duration of the process (several hours being usually necessary, depending on the required noble metal loading), the application of high amounts of catalytic coatings leads to coatings having a very limited lifetime.
SUMMARY OF THE INVENTION
Under a first aspect, the present invention relates to an electrode for evolution of gaseous products in electrolysis cells consisting of a valve metal substrate coated with at least one first catalytic composition and with an outer catalytic composition, said at least one first catalytic composition comprising a mixture of oxides of a valve metal or of tin and of noble metals selected from the group of platinum metals (PM) or oxides thereof taken alone or in admixture, said at least one first catalytic composition obtained by thermal decomposition of precursors, said outer catalytic composition comprising noble metals selected from the group of platinum metals or oxides thereof taken alone or in admixture, said outer catalytic composition being deposited by means of a chemical or physical phase vapour deposition technique, the amount of noble metal on said first catalytic composition being higher than 5 g/m2 of surface and the amount of noble metal in said outer catalytic composition ranging between 0.1 and 3.0 g/m2 of surface.
The inventors have surprisingly found out that the deposition of one last catalytic layer, with the specified characteristics, through chemical or physical phase vapour allows obtaining an electrode with unexpected features both in terms of duration and of potential decrease.
In one embodiment, the first catalytic composition of the electrode according to the invention comprises titanium, iridium, ruthenium in form of metals or oxides.
SUMMARY OF THE INVENTION
Under a first aspect, the present invention relates to an electrode for evolution of gaseous products in electrolysis cells consisting of a valve metal substrate coated with at least one first catalytic composition and with an outer catalytic composition, said at least one first catalytic composition comprising a mixture of oxides of a valve metal or of tin and of noble metals selected from the group of platinum metals (PM) or oxides thereof taken alone or in admixture, said at least one first catalytic composition obtained by thermal decomposition of precursors, said outer catalytic composition comprising noble metals selected from the group of platinum metals or oxides thereof taken alone or in admixture, said outer catalytic composition being deposited by means of a chemical or physical phase vapour deposition technique, the amount of noble metal on said first catalytic composition being higher than 5 g/m2 of surface and the amount of noble metal in said outer catalytic composition ranging between 0.1 and 3.0 g/m2 of surface.
The inventors have surprisingly found out that the deposition of one last catalytic layer, with the specified characteristics, through chemical or physical phase vapour allows obtaining an electrode with unexpected features both in terms of duration and of potential decrease.
In one embodiment, the first catalytic composition of the electrode according to the invention comprises titanium, iridium, ruthenium in form of metals or oxides.
3 In one embodiment, the outer catalytic composition comprises ruthenium and/or iridium in form of metals or oxides.
In one embodiment, the specific noble metal loading in the first catalytic composition ranges between 6 and 8 g/m2 and the specific metal loading in the outer catalytic composition ranges between 1.5 and 2.5 g/m2.
Under another aspect, the invention relates to a method of manufacturing an electrode comprising the deposition of an outer catalytic composition by chemical or physical phase vapour deposition, preferably by reactive sputtering of noble metals selected in the group of platinum metals.
Under a further aspect the invention relates to the reactivation of a used electrode comprising the chemical or physical phase vapour deposition of an outer catalytic composition including noble metals selected from the group of platinum metals or oxides thereof taken alone or in admixture.
Under a further aspect, the invention relates to an electrolysis cell of alkali chloride solutions, for instance a sodium chloride brine electrolysis cell directed to producing chlorine and caustic soda, which effects the anodic evolution of chlorine on an electrode as hereinbefore described.
The following examples are included to demonstrate particular embodiments of the invention, whose practicability has been largely verified in the claimed range of values.
It should be appreciated by those of skill in the art that the compositions and techniques disclosed in the examples which follow represent compositions and techniques discovered by the inventors to function well in the practice of the invention;
however, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the scope of the invention.
In one embodiment, the specific noble metal loading in the first catalytic composition ranges between 6 and 8 g/m2 and the specific metal loading in the outer catalytic composition ranges between 1.5 and 2.5 g/m2.
Under another aspect, the invention relates to a method of manufacturing an electrode comprising the deposition of an outer catalytic composition by chemical or physical phase vapour deposition, preferably by reactive sputtering of noble metals selected in the group of platinum metals.
Under a further aspect the invention relates to the reactivation of a used electrode comprising the chemical or physical phase vapour deposition of an outer catalytic composition including noble metals selected from the group of platinum metals or oxides thereof taken alone or in admixture.
Under a further aspect, the invention relates to an electrolysis cell of alkali chloride solutions, for instance a sodium chloride brine electrolysis cell directed to producing chlorine and caustic soda, which effects the anodic evolution of chlorine on an electrode as hereinbefore described.
The following examples are included to demonstrate particular embodiments of the invention, whose practicability has been largely verified in the claimed range of values.
It should be appreciated by those of skill in the art that the compositions and techniques disclosed in the examples which follow represent compositions and techniques discovered by the inventors to function well in the practice of the invention;
however, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the scope of the invention.
4 A sample of titanium mesh of 10 cm x 10 cm size was blasted with corundum, cleaning the residues with a jet of compressed air. The sample was then degreased using acetone in a ultrasonic bath for about 10 minutes. After drying, the sample was dipped into an aqueous solution containing 250 g/I of NaOH and 50 g/I of KNO3 at about 100 C
for 1 hour. After the alkaline treatment, the sample was rinsed in deionised water at 60 C for three times, changing the liquid every time. The last rinse was carried out adding a small quantity of HCI (about 1 ml per litre of solution). An air drying was effected, observing the formation of a brown hue due to the growth of a thin film of TiOx.
100 ml of a hydroalcoholic solution containing RuCI3*3H20, H2IrCle6H20, TiCI3 in a mixture of water and 2-propanol acidified with HCI were then prepared, having a molar composition of 36% Ru, 20% Ir, 44% Ti referred to the metals.
The solution was applied to the sample of titanium mesh by brushing in five coats; after each coat, a drying at 100-110 C for about 10 minutes was carried out, followed by a thermal treatment of 15 minutes at 450 C. The sample was cooled in air each time prior to applying the subsequent coat.
At the end of the whole procedure, a total noble metal loading of 9 g/m2, expressed as the sum of Ru and Ir referred to the metals, was obtained.
The thus obtained electrode was identified as sample No. 1.
A sample of titanium mesh of 10 cm x 10 cm size was blasted with corundum, cleaning the residues with a jet of compressed air. The sample was then degreased using acetone in a ultrasonic bath for about 10 minutes. After drying, the sample was dipped into an aqueous solution containing 250 g/I of NaOH and 50 g/I of KNO3 at about 100 C
for 1 hour. After the alkaline treatment, the sample was rinsed in deionised water at 60 C for three times, changing the liquid every time. The last rinse was carried out
for 1 hour. After the alkaline treatment, the sample was rinsed in deionised water at 60 C for three times, changing the liquid every time. The last rinse was carried out adding a small quantity of HCI (about 1 ml per litre of solution). An air drying was effected, observing the formation of a brown hue due to the growth of a thin film of TiOx.
100 ml of a hydroalcoholic solution containing RuCI3*3H20, H2IrCle6H20, TiCI3 in a mixture of water and 2-propanol acidified with HCI were then prepared, having a molar composition of 36% Ru, 20% Ir, 44% Ti referred to the metals.
The solution was applied to the sample of titanium mesh by brushing in five coats; after each coat, a drying at 100-110 C for about 10 minutes was carried out, followed by a thermal treatment of 15 minutes at 450 C. The sample was cooled in air each time prior to applying the subsequent coat.
At the end of the whole procedure, a total noble metal loading of 9 g/m2, expressed as the sum of Ru and Ir referred to the metals, was obtained.
The thus obtained electrode was identified as sample No. 1.
A sample of titanium mesh of 10 cm x 10 cm size was blasted with corundum, cleaning the residues with a jet of compressed air. The sample was then degreased using acetone in a ultrasonic bath for about 10 minutes. After drying, the sample was dipped into an aqueous solution containing 250 g/I of NaOH and 50 g/I of KNO3 at about 100 C
for 1 hour. After the alkaline treatment, the sample was rinsed in deionised water at 60 C for three times, changing the liquid every time. The last rinse was carried out
5 PCT/EP2011/073605 adding a small quantity of HCI (about 1 ml per litre of solution). An air drying was effected, observing the formation of a brown hue due to the growth of a thin film of TiOx.
The mesh sample was then introduced into the vacuum chamber of the reactive 5 sputtering equipment.
Upon establishing a dynamic vacuum of about 50 E-4 mbar feeding an oxygen mixture with 20% argon, the sputtering targets were polarised at the following powers:
ruthenium 35 W, iridium 24 W, titanium 250 W. The target-electrode substrate gap was about 10 centimetres.
The process of deposition was carried out, at the same conditions, alternatively on the two sides of the titanium mesh for an overall duration of 220 minutes. The thus obtained electrode presented a catalytic coating of about 1 micron and a total noble metal loading of about 9 g/m2, expressed as the sum of Ru and Ir referred to the metals.
The thus obtained electrode was identified as sample No. 2.
A sample of titanium mesh of 10 cm x 10 cm size was blasted with corundum, cleaning the residues with a jet of compressed air. The sample was then degreased using acetone in a ultrasonic bath for about 10 minutes. After drying, the sample was dipped into an aqueous solution containing 250 g/I of NaOH and 50 g/I of KNO3 at about 100 C
for 1 hour. After the alkaline treatment, the sample was rinsed in deionised water at 60 C for three times, changing the liquid every time. The last rinse was carried out adding a small quantity of HCI (about 1 ml per litre of solution). An air drying was effected, observing the formation of a brown hue due to the growth of a thin film of TiOx.
100 ml of a hydroalcoholic solution containing RuCI3*3H20, H2IrCI6*6H20, TiCI3 in a mixture of water and 2-propanol acidified with HCI were then prepared, having a molar composition of 36% Ru, 20% Ir, 44% Ti referred to the metals.
The mesh sample was then introduced into the vacuum chamber of the reactive 5 sputtering equipment.
Upon establishing a dynamic vacuum of about 50 E-4 mbar feeding an oxygen mixture with 20% argon, the sputtering targets were polarised at the following powers:
ruthenium 35 W, iridium 24 W, titanium 250 W. The target-electrode substrate gap was about 10 centimetres.
The process of deposition was carried out, at the same conditions, alternatively on the two sides of the titanium mesh for an overall duration of 220 minutes. The thus obtained electrode presented a catalytic coating of about 1 micron and a total noble metal loading of about 9 g/m2, expressed as the sum of Ru and Ir referred to the metals.
The thus obtained electrode was identified as sample No. 2.
A sample of titanium mesh of 10 cm x 10 cm size was blasted with corundum, cleaning the residues with a jet of compressed air. The sample was then degreased using acetone in a ultrasonic bath for about 10 minutes. After drying, the sample was dipped into an aqueous solution containing 250 g/I of NaOH and 50 g/I of KNO3 at about 100 C
for 1 hour. After the alkaline treatment, the sample was rinsed in deionised water at 60 C for three times, changing the liquid every time. The last rinse was carried out adding a small quantity of HCI (about 1 ml per litre of solution). An air drying was effected, observing the formation of a brown hue due to the growth of a thin film of TiOx.
100 ml of a hydroalcoholic solution containing RuCI3*3H20, H2IrCI6*6H20, TiCI3 in a mixture of water and 2-propanol acidified with HCI were then prepared, having a molar composition of 36% Ru, 20% Ir, 44% Ti referred to the metals.
6 The solution was applied to the sample of titanium mesh by brushing in five coats; after each coat, a drying at 100-110 C for about 10 minutes was carried out, followed by a thermal treatment of 15 minutes at 450 C. The sample was cooled in air each time prior to applying the subsequent coat.
At the end of the whole procedure, a total noble metal loading of 7 g/m2, expressed as the sum of Ru and Ir referred to the metals, was obtained.
The semi-finished electrode was then introduced into the vacuum chamber of the reactive sputtering equipment.
Upon establishing a dynamic vacuum of about 100 E-4 mbar feeding an oxygen mixture with 20% argon, the sputtering targets were polarised at the following powers:
ruthenium 30 W, iridium 35 W. The target-electrode substrate gap was about 10 centimetres. To confer optimal properties to the resulting coating, the substrate was also subjected to a residual polarisation of about 150 V.
The process of deposition was carried out, at the same conditions, alternatively on the two sides of the electrode for an overall duration of 40 minutes. The thus obtained electrode had an outer catalytic coating about 0.1 pm thick and a total noble metal loading of about 9 g/m2, expressed as the sum of Ru and Ir referred to the metals.
The thus obtained electrode was identified as sample No. 3.
The samples of the previous examples were characterised as anodes for chlorine evolution in a lab cell fed with a sodium chloride brine at a concentration of 200 g/I, strictly controlling the pH at 3. Table 1 reports chlorine overvoltage measured at a current density of 4 kA/m2 and the volume percentage of oxygen in product chlorine.
Sample No. r1C12 (mV)
At the end of the whole procedure, a total noble metal loading of 7 g/m2, expressed as the sum of Ru and Ir referred to the metals, was obtained.
The semi-finished electrode was then introduced into the vacuum chamber of the reactive sputtering equipment.
Upon establishing a dynamic vacuum of about 100 E-4 mbar feeding an oxygen mixture with 20% argon, the sputtering targets were polarised at the following powers:
ruthenium 30 W, iridium 35 W. The target-electrode substrate gap was about 10 centimetres. To confer optimal properties to the resulting coating, the substrate was also subjected to a residual polarisation of about 150 V.
The process of deposition was carried out, at the same conditions, alternatively on the two sides of the electrode for an overall duration of 40 minutes. The thus obtained electrode had an outer catalytic coating about 0.1 pm thick and a total noble metal loading of about 9 g/m2, expressed as the sum of Ru and Ir referred to the metals.
The thus obtained electrode was identified as sample No. 3.
The samples of the previous examples were characterised as anodes for chlorine evolution in a lab cell fed with a sodium chloride brine at a concentration of 200 g/I, strictly controlling the pH at 3. Table 1 reports chlorine overvoltage measured at a current density of 4 kA/m2 and the volume percentage of oxygen in product chlorine.
Sample No. r1C12 (mV)
7 The samples of the previous examples were also subjected to a duration test.
Said duration test is the simulation in a separated cell of industrial electrolysis conditions as regards electrolyte concentration and temperature, but at a current density conveniently increased up to a value 2-3 times higher than the nominal one for the sake of accelerating the experimental response. Table 2 reports the precious metal lost per unit current.
Sample No. Loss of precious metal per unit current (mgpm/kAh) 1 0.016 2 0.5 3 0.005 The previous description is not intended to limit the invention, which may be used according to different embodiments without departing from the scopes thereof, and whose extent is univocally defined by the appended claims.
Throughout the description and claims of the present application, the term "comprise"
and variations thereof such as "comprising" and "comprises" are not intended to exclude the presence of other elements or additives.
The discussion of documents, acts, materials, devices, articles and the like is included in this specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common general knowledge in the field relevant to the present invention before the priority date of each claim of this application.
Said duration test is the simulation in a separated cell of industrial electrolysis conditions as regards electrolyte concentration and temperature, but at a current density conveniently increased up to a value 2-3 times higher than the nominal one for the sake of accelerating the experimental response. Table 2 reports the precious metal lost per unit current.
Sample No. Loss of precious metal per unit current (mgpm/kAh) 1 0.016 2 0.5 3 0.005 The previous description is not intended to limit the invention, which may be used according to different embodiments without departing from the scopes thereof, and whose extent is univocally defined by the appended claims.
Throughout the description and claims of the present application, the term "comprise"
and variations thereof such as "comprising" and "comprises" are not intended to exclude the presence of other elements or additives.
The discussion of documents, acts, materials, devices, articles and the like is included in this specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common general knowledge in the field relevant to the present invention before the priority date of each claim of this application.
Claims (7)
1. An electrode for evolution of gaseous products in electrochemical cells consisting of a valve metal substrate coated with at least one first catalytic composition and an outer catalytic composition, said at least one first catalytic composition comprising a mixture of:
i) a valve metal, an oxide of a valve metal, tin, or an oxide of tin; and ii) one or more noble metals selected from the group consisting of a platinum group metal, an oxide of a platinum group metal and an admixture thereof;
wherein said at least one first catalytic composition is obtained by thermal decomposition of precursors;
wherein said outer catalytic composition is deposited by a chemical or physical vapor deposition technique;
wherein the amount of noble metal in said at least one first catalytic composition is greater than 5 g/m2; and wherein said outer catalytic composition comprises an amount of noble metal which ranges from 0.1 to 3.0 g/m2.
i) a valve metal, an oxide of a valve metal, tin, or an oxide of tin; and ii) one or more noble metals selected from the group consisting of a platinum group metal, an oxide of a platinum group metal and an admixture thereof;
wherein said at least one first catalytic composition is obtained by thermal decomposition of precursors;
wherein said outer catalytic composition is deposited by a chemical or physical vapor deposition technique;
wherein the amount of noble metal in said at least one first catalytic composition is greater than 5 g/m2; and wherein said outer catalytic composition comprises an amount of noble metal which ranges from 0.1 to 3.0 g/m2.
2. The electrode according to claim 1, wherein said mixture of said at least one first catalytic composition comprises a mixture of titanium, iridium and ruthenium.
3. The electrode according to claim 1, wherein said outer catalytic composition comprises ruthenium and/or iridium.
4. The electrode according to any one of claims 1 to 3, wherein the specific noble metal loading of said at least one first catalytic composition is 6 to 8 g/m2 and the specific noble metal loading of said outer catalytic composition is 1.5 to 2.5 g/m2.
5. A method for manufacturing the electrode of any one of claims 1 to 4 comprising the deposition of said outer catalytic composition by a chemical or physical vapor deposition technique.
6. A method for manufacturing the electrode of any one of claims 1 to 4 comprising the deposition of said outer catalytic composition as a mixture of oxides by reactive sputtering of noble metals selected from the group of platinum metals.
7. An electrolysis cell comprising a cathodic compartment containing a cathode and an anodic compartment containing an anode separated by a membrane or diaphragm, said anodic compartment being fed with an alkali chloride brine, wherein said anode of said anodic compartment is the electrode of any one of claims 1 to 4.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ITMI2010A002354 | 2010-12-22 | ||
| IT002354A ITMI20102354A1 (en) | 2010-12-22 | 2010-12-22 | ELECTRODE FOR ELECTROLYTIC CELL |
| PCT/EP2011/073605 WO2012085095A2 (en) | 2010-12-22 | 2011-12-21 | Electrode for electrolytic cell |
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| Publication Number | Publication Date |
|---|---|
| CA2815137A1 CA2815137A1 (en) | 2012-06-28 |
| CA2815137C true CA2815137C (en) | 2019-03-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2815137A Expired - Fee Related CA2815137C (en) | 2010-12-22 | 2011-12-21 | Platinum-group-metal activated multi-layer electrode for electrolytic cell |
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| Country | Link |
|---|---|
| US (1) | US20130228450A1 (en) |
| EP (2) | EP2655693B1 (en) |
| JP (1) | JP6247535B2 (en) |
| KR (2) | KR20130143624A (en) |
| CN (1) | CN103249872B (en) |
| AR (1) | AR083989A1 (en) |
| AU (1) | AU2011347262B2 (en) |
| BR (1) | BR112013014015B1 (en) |
| CA (1) | CA2815137C (en) |
| CL (1) | CL2013001620A1 (en) |
| CO (1) | CO6741167A2 (en) |
| DK (1) | DK2655693T3 (en) |
| EA (1) | EA024356B1 (en) |
| IL (1) | IL225905A (en) |
| IT (1) | ITMI20102354A1 (en) |
| MX (1) | MX354730B (en) |
| SG (1) | SG190951A1 (en) |
| TW (1) | TW201226631A (en) |
| WO (1) | WO2012085095A2 (en) |
| ZA (1) | ZA201302944B (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI731845B (en) * | 2014-11-24 | 2021-07-01 | 義商第諾拉工業公司 | Anode for electrolytic evolution of chlorine |
| KR102272749B1 (en) * | 2016-11-22 | 2021-07-06 | 아사히 가세이 가부시키가이샤 | Electrode for electrolysis |
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| GB1195871A (en) * | 1967-02-10 | 1970-06-24 | Chemnor Ag | Improvements in or relating to the Manufacture of Electrodes. |
| US3929608A (en) * | 1970-07-29 | 1975-12-30 | Solvay | Catalytic material for electrodes |
| US3684543A (en) * | 1970-11-19 | 1972-08-15 | Patricia J Barbato | Recoating of electrodes |
| GB1352872A (en) * | 1971-03-18 | 1974-05-15 | Ici Ltd | Electrodes for electrochemical processes |
| SU522284A1 (en) * | 1974-05-22 | 1976-07-25 | Предприятие П/Я В-2287 | Method for restoring spent coating activity |
| US4331528A (en) * | 1980-10-06 | 1982-05-25 | Diamond Shamrock Corporation | Coated metal electrode with improved barrier layer |
| DE3270207D1 (en) * | 1981-04-06 | 1986-05-07 | Eltech Systems Corp | Recoating of electrodes |
| JPS6022071B2 (en) * | 1982-01-14 | 1985-05-30 | ペルメレツク電極株式会社 | Method for manufacturing electrodes for electrolysis |
| US4696731A (en) * | 1986-12-16 | 1987-09-29 | The Standard Oil Company | Amorphous metal-based composite oxygen anodes |
| CN1012743B (en) * | 1987-08-22 | 1991-06-05 | 福建省冶金工业研究所 | Titanium anode for electrochemical industry |
| GB9018953D0 (en) * | 1990-08-31 | 1990-10-17 | Ici Plc | Electrode |
| TW197475B (en) * | 1990-12-26 | 1993-01-01 | Eltech Systems Corp | |
| JP3212327B2 (en) | 1991-08-30 | 2001-09-25 | ペルメレック電極株式会社 | Electrode for electrolysis |
| GB9316926D0 (en) * | 1993-08-13 | 1993-09-29 | Ici Plc | Electrode |
| GB9316930D0 (en) * | 1993-08-13 | 1993-09-29 | Ici Plc | Electrode |
| US6217729B1 (en) * | 1999-04-08 | 2001-04-17 | United States Filter Corporation | Anode formulation and methods of manufacture |
| FR2797646B1 (en) * | 1999-08-20 | 2002-07-05 | Atofina | CATHODE FOR USE IN THE ELECTROLYSIS OF AQUEOUS SOLUTIONS |
| ITMI20021128A1 (en) * | 2002-05-24 | 2003-11-24 | De Nora Elettrodi Spa | ELECTRODE FOR GAS DEVELOPMENT AND METHOD FOR ITS OBTAINING |
| JP2008156684A (en) * | 2006-12-22 | 2008-07-10 | Tanaka Kikinzoku Kogyo Kk | Anode electrode for hydrochloric acid electrolysis |
| CN101626846B (en) * | 2007-04-18 | 2011-12-14 | 德诺拉工业有限公司 | electrodes with mechanically roughened surface for electrochemical applications |
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2010
- 2010-12-22 IT IT002354A patent/ITMI20102354A1/en unknown
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2011
- 2011-10-25 TW TW100138559A patent/TW201226631A/en unknown
- 2011-11-24 AR ARP110104391A patent/AR083989A1/en active IP Right Grant
- 2011-12-21 US US13/885,118 patent/US20130228450A1/en not_active Abandoned
- 2011-12-21 JP JP2013545366A patent/JP6247535B2/en not_active Expired - Fee Related
- 2011-12-21 AU AU2011347262A patent/AU2011347262B2/en not_active Ceased
- 2011-12-21 SG SG2013042270A patent/SG190951A1/en unknown
- 2011-12-21 MX MX2013006271A patent/MX354730B/en active IP Right Grant
- 2011-12-21 CA CA2815137A patent/CA2815137C/en not_active Expired - Fee Related
- 2011-12-21 BR BR112013014015-1A patent/BR112013014015B1/en not_active IP Right Cessation
- 2011-12-21 KR KR1020137018744A patent/KR20130143624A/en active Application Filing
- 2011-12-21 KR KR1020187010910A patent/KR101886032B1/en active IP Right Grant
- 2011-12-21 EA EA201390927A patent/EA024356B1/en not_active IP Right Cessation
- 2011-12-21 WO PCT/EP2011/073605 patent/WO2012085095A2/en active Application Filing
- 2011-12-21 EP EP11802731.7A patent/EP2655693B1/en not_active Not-in-force
- 2011-12-21 CN CN201180055655.3A patent/CN103249872B/en not_active Expired - Fee Related
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- 2013-04-23 IL IL225905A patent/IL225905A/en active IP Right Grant
- 2013-06-04 CO CO13135216A patent/CO6741167A2/en not_active Application Discontinuation
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| ITMI20102354A1 (en) | 2012-06-23 |
| EA201390927A1 (en) | 2013-11-29 |
| JP2014505166A (en) | 2014-02-27 |
| EP3118351A1 (en) | 2017-01-18 |
| IL225905A (en) | 2015-08-31 |
| ZA201302944B (en) | 2014-06-25 |
| CN103249872A (en) | 2013-08-14 |
| MX2013006271A (en) | 2013-08-01 |
| KR20180043398A (en) | 2018-04-27 |
| EP2655693A2 (en) | 2013-10-30 |
| EA024356B1 (en) | 2016-09-30 |
| US20130228450A1 (en) | 2013-09-05 |
| WO2012085095A3 (en) | 2012-10-04 |
| DK2655693T3 (en) | 2017-02-20 |
| WO2012085095A2 (en) | 2012-06-28 |
| CN103249872B (en) | 2016-08-10 |
| CO6741167A2 (en) | 2013-08-30 |
| AR083989A1 (en) | 2013-04-10 |
| BR112013014015B1 (en) | 2020-05-12 |
| KR20130143624A (en) | 2013-12-31 |
| IL225905A0 (en) | 2013-07-31 |
| AU2011347262B2 (en) | 2016-03-31 |
| JP6247535B2 (en) | 2017-12-13 |
| CA2815137A1 (en) | 2012-06-28 |
| AU2011347262A1 (en) | 2013-05-23 |
| SG190951A1 (en) | 2013-07-31 |
| EP2655693B1 (en) | 2016-11-16 |
| CL2013001620A1 (en) | 2013-11-08 |
| KR101886032B1 (en) | 2018-08-07 |
| MX354730B (en) | 2018-03-15 |
| BR112013014015A2 (en) | 2016-09-13 |
| TW201226631A (en) | 2012-07-01 |
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