Electrochemical sensing of carbon monoxide

• US 4,522,690 A
• Filed: 12/01/1983
• Issued: 06/11/1985
• Est. Priority Date: 12/01/1983
• Status: Expired due to Term

• Current Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Original Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Inventors: Venkatasetty, Hanumanthaiya V.
• Primary Examiner(s): TUNG, TA HSUNG
• Application Number:
  US06/557,072
• Time in Patent Office: 558 Days
• Field of Search: 204/1 T, 204/1 K, 204/1 N, 204/1 F, 204/415, 204/400, 204/414, 204/412
• US Class Current: 205/783
• CPC Class Codes: G01N 27/4045 for gases other than oxygen

Abstract

Apparatus and method for an electrochemical sensor for carbon monoxide detection in a gelled aprotic organic nonaqueous electrolyte solution.

Claims

1. A method for detecting the presence of a plurality of toxic agents comprising the steps of:

providing electrochemical cell means having an electrode configuration comprising a plurality of electrodes including a platinum working electrode, a platinum counter electrode and an Ag/Ag⁺ reference electrode;

providing a nonaqueous gelled aprotic electrolyte solution in the electrochemical cell means, said solution comprising an aprotic organic solvent selected from the group consisting of γ

-butyrolactone and propylene carbonate, an amount of lithium perchlorate electrolyte and polyethylene oxide gelling agent;

exposing the electrochemical cell means to an atmosphere suspected of containing the gas of interest;

providing electrical source means and connecting the source means to the electrode configuration to energize the cell means; and

providing means for measuring the current flowing between said sensing electrode and said counter electrode.

2. An electrochemical sensor for toxic gas detection comprising:

electrochemical cell means having therein an electrode configuration comprising a plurality of electrodes including a platinum working electrode, a platinum counter electrode and an Ag/Ag⁺ reference electrode;

a nonaqueous gelled aprotic electrolyte solution in said cell means, said electrolyte solution comprising an aprotic organic solvent selected from the group consisting of γ

-butyrolactone and propylene carbonate, an amount of lithium perchlorate electrolyte and an amount of polyethylene oxide gelling agent;

adjustable potential electrical source means, to energize said electrochemical cell means at desired potentials, connected across said working and counter electrodes; and

current measuring means connected across said working and counter electrodes.

3. The sensor of claim 2 wherein the nonaqueous electrolyte solvent is γ

-butyrolactone.

4. The sensor of claim 3 wherein the concentration of lithium perchlorate is about 1.0M.

5. The sensor of claim 4 wherein the amount of said polyethylene oxide is about 1% by weight based on the weight of the solution.

6. The sensor of claim 5 wherein said toxic gas to be detected is CO.

7. The sensor of claim 2 wherein said working and counter electrodes are in the form of a thin platinum film.

8. The sensor of claim 2 wherein the nonaqueous electrolyte solvent is propylene carbonate.

9. The sensor of claim 8 wherein the concentration of the electrolyte is about 0.75M.

10. The sensor of claim 9 wherein the amount of said polyethylene oxide is about 1% by weight based on the weight of the solution.

11. The sensor of claim 10 wherein said toxic gas to be detected is CO.

12. An electrochemical sensor for toxic gas detection comprising:

electrochemical cell means having therein an electrode configuration comprising a plurality of electrodes including a platinum electrode working, a platinum counter electrode and an Ag/Ag⁺ reference electrode;

a nonaqueous gelled aprotic electrolyte solution in said cell means, said solution comprising an aprotic organic solvent selected from the group consisting of γ

-butyrolactone and propylene carbonate, an electrolyte comprising an amount of lithium perchlorate and an amount of tetraethylammonium perchlorate and an amount of polyethylene oxide gelling agent;

adjustable potential electrical source means, to energize said electrochemical cell means at desired potentials, connected across said working and counter electrodes; and

current measuring means connected across said working and counter electrodes.

13. The sensor of claim 12 wherein the non-aqueous electrolyte solvent is γ

-butyrolactone.

14. The sensor of claim 13 wherein the concentration of said tetraethylammonium perchlorate is about 0.1M.

15. The sensor of claim 14 wherein the amount of said polyethylene oxide is about 1% by weight based on the weight of the solution.

16. The sensor of claim 14 wherein the toxic gas to be detected is CO.

17. The sensor of claim 12 wherein said working and counter electrodes are in the form of a thin platinum film.