ELECTRODE FOR ANODIC STRIPPING VOLTAMMETRY

• US 3,855,099 A
• Filed: 01/29/1973
• Issued: 12/17/1974
• Est. Priority Date: 08/02/1971
• Status: Expired due to Term

• Current Assignee: Esa S.R.O. (Logisteed Limited)
• Original Assignee: Wayne R. Matson
• Inventors: Matson, Wayne R.
• Primary Examiner(s): Edmundson, F. C.
• Application Number:
  US05/327,788
• Time in Patent Office: 687 Days
• Field of Search: 204/29R,195F,294
• US Class Current: 204/434
• CPC Class Codes: G01N 27/308 at least partially made of carbon

Abstract

An electrode for anodic stripping voltammetry comprises an electrically conductive, chemically inert support such as a graphite or similar support having a lateral electrode surface with an electrode metal on the surface. The electrode can be prepared by impregnating a support such as a graphite rod with a film forming insulator, such as a wax, laying bare surface areas of graphite particles, and thereafter depositing a metal on the graphite. Metals include mercury, gold, platinum, bismuth or bismuth amalgam, silver and others.

Claims

1. AN ELECTRODE FOR ANODIC STRIPPING VOLTAMMETRY ADDAPTED FOR TESTING FOR AT LEAST ONE PREDETERMINED ION IN AN AQUEOUS SAMPLE COMPRISING A PROOUS, ELECTRICALLY CONDUCTING ROD HAVING AN ACTIVE LATERAL ELECTRODE SURFACE OF MEASURED PREDETERMINED AREA ACROSS WITH ESSENTIALLY THE ENTIRE AQUEOUS SAMPLE CAN BE CIRCULATED SAID LATERAL SURFACE BEING ADAPTED TO BE POSITIONED ESSENTIALLY VIRTICALLY WHEN THE ELECTRODE IS EMPOLYED IN A WORKING MODE, SAID ROD COMPRISING PARTICLES OF AN AVERAGE SIZE BETWEEN ABOUT 0.2 AND ABOUT 2 MICRONS ADHERING TOGETHER TO FORM SAID ROD, AN IMPREGNATED FILM FORMING MATERIAL SEALING THE PORES OF SAID ROD AND PREVENTING PENETRATION THEREOF BY SAID AQUEOUS SAMPLE;

THE ELECTRODE SURFACE BEING POLISHED AD HAVING A STRUCTURALLY SMOOTH SURFACE COMPRISING A SURFACE WHOSE AREA COMPRISES A CONTINOUS SURFACE OF SAID FILM FORMING MATERIAL AND A MULTIPLICITY OF ISLANDS OF SAID ELECTRICALLY CONDUCTING ROD MATERIAL EACH HAVING AN AVERAGE AREA LESS THAN ABOUT 1 X 10-12 SQUARE CENTIMETERS,

2. The electrode of claim 1 adapted for testing for mercury wherein the electrode metal is gold.

3. The electrode of claim 1 adapted for testing for phosphate ion wherein the electrode metal is bismuth.

4. The electrode of claim 1 adapted for testing for nickel wherein the electrode metal is platinum.

5. The electrode of claim 1 adapted for testing for sulphide ion wherein the electrode metal is silver.

6. An electrode for anodic stripping voltammetry adapted for testing for an ion in an aqueous sample comprising a graphite rod having an active lateral electrode surface of measured predetermined area, said lateral surface being adapted to be positioned essentially vertically when the electrode is employed in a working mode, said rod comprising graphite particles of an average size between about 0.2 and about 2 microns impregnated with a wax having a melting point between about 60* and 65C., the electrode surface being polished and having a structurally smooth surface comprising a surface whose area comprises a continuous surface of said wax and a multiplicity of islands of graphite each having an average area less than about 1 X 10116 square centimeters and deposited on said islands a multiplicity of islands of a metal lower in the electro-motive series than the ion to be tested and capable of absorbing said ion upon electrolytic reduction.

7. The electrode of claim 6 adapted for testing for mercury wherein the electrode metal is gold.

8. The electrode of claim 6 adapted for testing for phosphate ion wherein the electrode metal is bismuth, said electrode metal being selected from the group consisting of gold, silver, bismuth and platinum.

9. The electrode of claim 6 adapted for testing for nickel wherein the electrode metal is platinum.

10. The electrode of claim 6 adapted for testing for sulphide ion wherein the electrode metal is silver.