Voltametric analysis apparatus and method

• US 5,217,112 A
• Filed: 09/04/1991
• Issued: 06/08/1993
• Est. Priority Date: 09/04/1991
• Status: Expired due to Fees

• Current Assignee: Amy C. Almon
• Original Assignee: Amy C. Almon
• Inventors: Almon, Amy C.
• Primary Examiner(s): Niebling, John
• Assistant Examiner(s): Leader, William T.
• Application Number:
  US07/754,841
• Time in Patent Office: 643 Days
• Field of Search: 204/412, 204/404, 204/400, 204/153.1, 204/153.11, 324/425
• US Class Current: 205/794.5
• CPC Class Codes: G01N 27/27 Association of two or more measuring systems or cells, each measuring a different parameter, where the measurement results may be either used independently, the systems or cells being physically associated, or combined to produce a value for a further parameter
• CPC Class Codes: G01N 27/49 Systems involving the determination of the current at a single specific value, or small range of values, of applied voltage for producing selective measurement of one or more particular ionic species

Abstract

An apparatus and method for electrochemical analysis of elements in solution. An auxiliary electrode 14, a reference electrode 18, and five working electrodes 20, 22, 26, 28, and 30 are positioned in a container 12 containing a sample solution 34. The working electrodes are spaced apart evenly from each other and auxiliary electrode 14 to minimize any inter-electrode interference that may occur during analysis. An electric potential is applied between auxiliary electrode 14 and each of the working electrodes 20, 22, 26, 28, and 30. Simultaneous measurements taken of the current flow through each of the working electrodes for each given potential in a potential range are used for identifying chemical elements present in sample solution 34 and their respective concentrations. Multiple working electrodes enable a more positive identification to be made by providing unique data characteristic of chemical elements present in the sample solution.

Claims

1. Apparatus for analyzing at least one chemical element carried by a solution, said apparatus for use in electrochemical analysis, said apparatus comprising:

an electrolytic cell dimensioned to hold said solution;

an auxiliary electrode positioned in said cell;

at least five working electrodes positioned in said cell, said at least five working electrodes spaced apart from said auxiliary electrode and each other, each of said at least five working electrodes composed of a different material thereby enabling at least five unique sets of electrochemical data to be generated for said at least one chemical element present in said solution;

each of the first five of said at least five working electrodes being made of one material selected from the group consisting of carbon, gold, nickel, platinum, and silver;

means for applying an electrical potential between said auxiliary electrode and each of said at least five working electrodes; and

means for measuring electrical current flowing through each of said at least five working electrodes.

2. The apparatus as recited in claim 1, wherein said at least five working electrodes are each spaced an equal distance from said auxiliary electrode and from each other.

3. A method for analyzing at least one chemical element, said method comprising the steps of:

positioning an auxiliary electrode and five working electrodes in a solution carrying said at least one chemical element to be analyzed, said five working electrodes being spaced apart from said auxiliary electrode and each other, said five working electrodes being made of a material selected from the group consisting of carbon, gold, nickel, platinum, and silver; and

no two of said five working electrodes being made of the same material;

simultaneously applying an electrical potential between said auxiliary electrode and each of said five working electrodes; and

measuring electrical current flowing through each of said five working electrodes.

4. The method as recited in claim 3, wherein said positioning step further comprises spacing said five working electrodes an equal distance from said auxiliary electrode and from each other.

5. The method as recited in claim 3, further comprising the step of varying said potential incrementally within a potential range so that said current through each of said five electrodes changes.