US4913780A
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Redox electrode for determining nitrous acid and nitrosyl compounds
Assignee: Mk Juchheim & Co GmbH
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Filing: 1988-08-12
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Granted: 1990-04-03
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Expires: 2008-08-12
Abstract
Abstract A redox electrode for determining nitrous acid and nitrosyl compounds in aqueous, acidic solution consists of a metallic conductor on which an n-conducting metal oxide surface is present.
Inventors
- 👤 Wolfgang Habermann
- 👤 Peter Hammes
- 👤 Reinhard Messlinger
- 👤 Manered Munzinger
- 👤 Helmut Froehlich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:05
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/28; G01N27/30
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
84 words
A redox electrode for determining nitrous acid and nitrosyl compounds in aqueous, acidic solution, wherein the electrode core consists essentially of a metallic conductor on which an n-conducting metal oxide surface having a conductivity k of from 10 -7 to 1×10 2 Ω -1 cm -1 is present, and wherein said redox electrode is responsive to the presence of nitrous acid and nitrosyl ions in aqueous acidic solution by producing a potential that correlates to the concentration of the nitrous acid and nitrosyl compounds.
Claim 2
Dependent Claim
84 words
A redox electrode for determining nitrous acid and nitrosyl compounds in aqueous, acidic solution, wherein the electrode core consists essentially of a metallic conductor on which an n-conducting metal oxide surface having a conductivity k of from 10 -7 to 1×10 2 Ω -1 cm -1 is present, and wherein said redox electrode is responsive to the presence of nitrous acid and nitrosyl ions in aqueous acidic solution by producing a potential that correlates to the concentration of the nitrous acid and nitrosyl compounds.
Claim 3
Dependent Claim
26 words
The redox electrode of claim 1, wherein a metal of subgroups IV to VI of the Periodic Table of elements is used as the electrode core.
Claim 4
Dependent Claim
49 words
The redox electrode of claim 2, wherein a metal selected from the group consisting of tungsten, molybdenum, tantalum, niobium and titanium is used as the electrode core, and wherein the electrical conductivity of the metal oxide surface is from 10 -6 to 1×10 1 Ω -1 cm -1 .
Claim 5
Dependent Claim
27 words
The redox electrode of claim 1, wherein the n-conducting metal oxide surface consists of an oxide of the elements: tungsten, molybdenum, vanadium, tantalum, titanium or mixtures thereof.
Claim 6
Dependent Claim
30 words
The redox electrode of claim 1, wherein the n-conducting metal oxide surface is produced by anodic oxidation of the electrode core in aqueous semiconcentrated sulfuric acid at about room temperature.
Claim 7
Dependent Claim
16 words
The redox electrode of claim 1, wherein the anodically produced oxide layer is <100 Å thick.
Claim 8
Dependent Claim
22 words
The redox electrode of claim 1, wherein the n-conducting surface consists of a metal oxide of the same metal as the core.
Claim 9
Independent Claim
68 words
A method for determining nitrous acid and nitrosyl concentrations in aqueous acidic solutions, the method comprising: measuring the potential of a redox electrode against a reference electrode, wherein the redox electrode is cathodically polarized against an auxiliary electrode and the redox electrode has a metallic core and an n-conducting metal oxide surface that has a conductivity of from 10 -7 to 1×10 2 Ω -1 cm -1 .
Claim 10
Independent Claim
68 words
A method for determining nitrous acid and nitrosyl concentrations in aqueous acidic solutions, the method comprising: measuring the potential of a redox electrode against a reference electrode, wherein the redox electrode is cathodically polarized against an auxiliary electrode and the redox electrode has a metallic core and an n-conducting metal oxide surface that has a conductivity of from 10 -7 to 1×10 2 Ω -1 cm -1 .
Claim 11
Dependent Claim
30 words
The method of claim 8 wherein the redox electrode has a metallic core that consists essentially of one of the metals of subgroups IV to VI of the periodic table.
Claim 12
Dependent Claim
26 words
The method of claim 9, wherein the metallic core is made from a metal selected from the group consisting of: tungsten, molybdenum, tantalum, niobium and titanium.
Claim 13
Dependent Claim
30 words
The method of claim 8, wherein the n-conducting metal oxide surface consists of an oxide of a metal selected from the group consisting of: tungsten, molybdenum, vanadium, tantalum and titanium.
Claim 14
Dependent Claim
16 words
The method of claim 8, wherein the metal oxide surface is greater than 100 Å thick.
Claim 15
Dependent Claim
78 words
A redox electrode, comprising: (a) a metallic electrode core, and (b) an n-conducting metal oxide surface, wherein the n-conducting metal oxide surface resides on the electrode core and has a conductivity k of from 10 -7 to 1×10 2 Ω -1 cm -1 , whereby the redox electrode has an ability to determine the concentration of nitrous acid and nitrosyl compounds in an aqueous acidic solution by measuring the electrodes potential against a reference electrode in the solution.
Claim 16
Dependent Claim
78 words
A redox electrode, comprising: (a) a metallic electrode core, and (b) an n-conducting metal oxide surface, wherein the n-conducting metal oxide surface resides on the electrode core and has a conductivity k of from 10 -7 to 1×10 2 Ω -1 cm -1 , whereby the redox electrode has an ability to determine the concentration of nitrous acid and nitrosyl compounds in an aqueous acidic solution by measuring the electrodes potential against a reference electrode in the solution.
Claim 17
Dependent Claim
23 words
The redox electrode of claim 13, wherein the purity of the metal(s) selected for the electrode core is greater than 99.9% by weight.
Claim 18
Dependent Claim
20 words
The redox electrode of claim 14, wherein the metallic oxide layer is greater than or equal to 80 Å thick.
Claim 19
Dependent Claim
17 words
The redox electrode of claim 15, wherein the metallic oxide layer is greater than 100 Å thick.
Claim 20
Dependent Claim
44 words
The redox electrode of claim 14, wherein the electrode core is made from a metal selected from the group consisting of: platinum, palladium, rhodium, ruthenium, iridium, osmium, copper, silver, gold, titanium, zirconium, hafnium, vanadium, niobium, tantalum, molybdenum, tungsten and an alloy of these metals.
Claim 21
Dependent Claim
27 words
The redox electrode of claim 17, wherein the electrode core is made from a metal selected from the group consisting of: tungsten, molybdenum, tantalum, niobium and titanium.
Claim 22
Dependent Claim
24 words
The redox electrode of claim 13, wherein metal oxides of the subgroups IV to VI of the periodic table are applied as n-conducting oxides.
Claim 23
Dependent Claim
26 words
The redox electrode of claim 13, wherein the conductivity of the metal oxide surface is from 10 -6 to 1×10 1 Ω -1 cm -1 .
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-04-02 | 1993-10-02 | 1994-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-02 | 1997-10-02 | 1998-04-03 | $3760.00 | Window Closed / Lapsed |
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