Patent US4013522A successfully refreshed from Google Patents.
US4013522A
Expired / Lapsed
US
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Method and apparatus for measuring the concentration of carbon monoxide
Assignee: Siemens AG
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Filing: 1975-01-20
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Granted: 1977-03-22
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Expires: 1995-01-20
Abstract
Abstract A method for determining the concentration of carbon monoxide in the air along with a measuring electrode for carrying out the method in which the degree of inhibition of an electrochemical reaction caused by the carbon monoxide, in particular the inhibition of a cathodic oxygen reduction, is determined. Preferably the measurement is made with the electric potential held constant and the change in current taking place during inhibition used as a measure of concentration.
Inventors
- 👤 Herbert Nischik
- 👤 Ferdinand von Sturm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:09
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/404; G01N27/4045
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
88 words
A method for determining the concentration of carbon monoxide in a measuring gas comprising the steps of: a. establishing an electrochemical reaction of the type causing current to flow using a electrolyte and a pair of electrodes, at least one of said electrodes being of a material whose activity is inhibited by carbon monoxide; b. feeding the measuring gas directly to said one of said electrodes; and c. determining the degree of inhibition of said electrochemical reaction which is caused by the carbon monoxide in said measuring gas.
Claim 2
Independent Claim
88 words
A method for determining the concentration of carbon monoxide in a measuring gas comprising the steps of: a. establishing an electrochemical reaction of the type causing current to flow using a electrolyte and a pair of electrodes, at least one of said electrodes being of a material whose activity is inhibited by carbon monoxide; b. feeding the measuring gas directly to said one of said electrodes; and c. determining the degree of inhibition of said electrochemical reaction which is caused by the carbon monoxide in said measuring gas.
Claim 3
Dependent Claim
23 words
The method according to claim 1 wherein said measuring gas is introduced into the electrolytic liquid which is in contact with one electrode.
Claim 4
Independent Claim
149 words
A method of determining the carbon monoxide content in a measuring gas comprising the steps of: a. providing a porous electrode having a cover layer on the electrode side which in an electrolyte saturated condition is gas tight, said electrode including means for feeding a gas to and discharging a gas from it and for coupling with an external contact; b. providing a separate counter electrode; c. disposing said first and second electrodes in an aqueous sulphuric acid electrolyte; d. applying a potential to said porous electrode to establish a cathodic oxygen reduction; e. maintaining one of the potential and current of said electrodes constant; f. feeding the measuring gas containing carbon monoxide to said porous electrode; and g. measuring the change in the one of potential and current which is not held constant as a measure of the inhibition of said cathodic oxygen reduction by said carbon monoxide.
Claim 5
Independent Claim
149 words
A method of determining the carbon monoxide content in a measuring gas comprising the steps of: a. providing a porous electrode having a cover layer on the electrode side which in an electrolyte saturated condition is gas tight, said electrode including means for feeding a gas to and discharging a gas from it and for coupling with an external contact; b. providing a separate counter electrode; c. disposing said first and second electrodes in an aqueous sulphuric acid electrolyte; d. applying a potential to said porous electrode to establish a cathodic oxygen reduction; e. maintaining one of the potential and current of said electrodes constant; f. feeding the measuring gas containing carbon monoxide to said porous electrode; and g. measuring the change in the one of potential and current which is not held constant as a measure of the inhibition of said cathodic oxygen reduction by said carbon monoxide.
Claim 6
Independent Claim
104 words
A method for determining the concentration of carbon monoxide in a measuring gas comprising the steps of: a. preparing a reference gas from the measuring gas by removing the carbon monoxide therefrom by catalytically oxidizing it to carbon dioxide through the use of a platinum asbestos catalyst; b. establishing an electrochemical reaction of the type causing current to flow using an electrolyte and a pair of electrodes; c. alternately feeding the measuring gas and the reference gas to one of said electrodes; and d. determining the degree of inhibition of said electrochemical reaction which is caused by the carbon monoxide in said measuring gas.
Claim 7
Independent Claim
104 words
A method for determining the concentration of carbon monoxide in a measuring gas comprising the steps of: a. preparing a reference gas from the measuring gas by removing the carbon monoxide therefrom by catalytically oxidizing it to carbon dioxide through the use of a platinum asbestos catalyst; b. establishing an electrochemical reaction of the type causing current to flow using an electrolyte and a pair of electrodes; c. alternately feeding the measuring gas and the reference gas to one of said electrodes; and d. determining the degree of inhibition of said electrochemical reaction which is caused by the carbon monoxide in said measuring gas.
Claim 8
Dependent Claim
15 words
The method according to claim 4 wherein said electrochemical reaction is a cathodic oxygen reduction.
Claim 9
Dependent Claim
45 words
The method according to claim 5 wherein said electrochemical reaction is carried out with a constant electrode potential and wherein the change of electric current occurring due to the inhibition caused by said carbon monoxide is determined as a measure of the carbon monoxide concentration.
Claim 10
Dependent Claim
42 words
The method according to claim 5 wherein said electrochemical reaction is carried out with a constant current and the change in electrode potential which occurs due to inhibition by the carbon monoxide is used as a measure of the carbon monoxide concentration.
Claim 11
Dependent Claim
21 words
The method according to claim 4 wherein the electrode to which said measuring gas is provided is a noble metal electrode.
Claim 12
Dependent Claim
11 words
The method according to claim 8 wherein said electrode comprises palladium.
Claim 13
Dependent Claim
16 words
The method according to claim 4 wherein an electrolytic liquid which is an acid is used.
Claim 14
Dependent Claim
13 words
The method according to claim 10 wherein said acid is aqueous sulphuric acid.
Claim 15
Dependent Claim
48 words
The method according to claim 4 wherein the electrode to which said measuring gas is fed is a porous electrode having a cover layer comprising asbestos paper containing a cation exchanger and a hydrophillic binder on its electrolyte side which in the electrolyte saturated condition is gas tight.
Claim 16
Dependent Claim
37 words
The method according to claim 4 wherein the electrode to which the carbon monoxide containing gas is fed is a porous electrode wherein the carbon monoxide containing gas is conducted through the electrode into the electrolytic liquid.
Claim 17
Dependent Claim
31 words
The method according to claim 4 and further including the step of alternatingly subjecting the electrode to which said measuring gas is fed to reverse anodic-cathodic polarization to maintain catalytic activity.
Claim 18
Independent Claim
74 words
A method for determining the concentration of carbon monoxide in a measuring gas comprising the steps of: a. establishing an electrochemical reaction of the type causing current to flow using an electrolyte consisting of aqueous sulphuric acid and a pair of electrodes; b. feeding the measuring gas to one of said electrodes; and c. determining the degree of inhibition of said electrochemical reaction which is caused by the carbon monoxide in said measuring gas.
Claim 19
Independent Claim
74 words
A method for determining the concentration of carbon monoxide in a measuring gas comprising the steps of: a. establishing an electrochemical reaction of the type causing current to flow using an electrolyte consisting of aqueous sulphuric acid and a pair of electrodes; b. feeding the measuring gas to one of said electrodes; and c. determining the degree of inhibition of said electrochemical reaction which is caused by the carbon monoxide in said measuring gas.
Claim 20
Independent Claim
89 words
A method for determining the concentration of carbon monoxide in a measuring gas comprising the steps of: a. establishing an electrochemical reaction of the type causing current to flow using an electrolyte and a pair of electrodes; b. feeding the measuring gas to one of said electrodes; c. determining the degree of inhibition of said electrochemical reaction which is caused by the carbon monoxide in said measuring gas; and d. alternatingly subjecting the electrode to which said measuring gas is fed to reverse anodic-cathodic polarization to maintain catalytic activity.
Claim 21
Independent Claim
89 words
A method for determining the concentration of carbon monoxide in a measuring gas comprising the steps of: a. establishing an electrochemical reaction of the type causing current to flow using an electrolyte and a pair of electrodes; b. feeding the measuring gas to one of said electrodes; c. determining the degree of inhibition of said electrochemical reaction which is caused by the carbon monoxide in said measuring gas; and d. alternatingly subjecting the electrode to which said measuring gas is fed to reverse anodic-cathodic polarization to maintain catalytic activity.
Claim 22
Dependent Claim
138 words
A measuring electrode for use in measuring carbon monoxide concentrations in a measuring gas comprising: a. an electrode body having a recess therein; b. a pressure plunger in the bottom of said recess; c. at least one contact making and gas distribution screen next to said plunger; d. a catalytically active layer for effecting an electrochemical reaction of the type causing a current to flow next to said screen; e. a cover layer next to said catalytically active layer; f. at least one support frame and a pressure ring next to said cover layer; g. means in said electrode body for applying pressure to said pressure plunger; h. said electrode body having holes therein for feeding and discharging gas to said catalytically active layer; and i. means for electrically connecting said catalytically active layer with an external contact.
Claim 23
Dependent Claim
138 words
A measuring electrode for use in measuring carbon monoxide concentrations in a measuring gas comprising: a. an electrode body having a recess therein; b. a pressure plunger in the bottom of said recess; c. at least one contact making and gas distribution screen next to said plunger; d. a catalytically active layer for effecting an electrochemical reaction of the type causing a current to flow next to said screen; e. a cover layer next to said catalytically active layer; f. at least one support frame and a pressure ring next to said cover layer; g. means in said electrode body for applying pressure to said pressure plunger; h. said electrode body having holes therein for feeding and discharging gas to said catalytically active layer; and i. means for electrically connecting said catalytically active layer with an external contact.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-21 | 1980-09-20 | 1981-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-21 | 1984-09-20 | 1985-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-21 | 1988-09-20 | 1989-03-22 | $7700.00 | Window Closed / Lapsed |