Electrode for electrochemical detectors

• US 5,096,560 A
• Filed: 05/29/1990
• Issued: 03/17/1992
• Est. Priority Date: 05/30/1989
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Petrochemical Co., Ltd. (Mitsubishi Chemical Group Corp.)
• Original Assignee: Mitsubishi Petrochemical Co., Ltd. (Mitsubishi Chemical Group Corp.)
• Inventors: Yoshida, Akira, Sawada, Yoshiaki, Takai, Nobuharu, Kageyama, Yoshiteru
• Primary Examiner(s): Niebling, John
• Assistant Examiner(s): Bell, Bruce F.
• Application Number:
  US07/529,543
• Time in Patent Office: 658 Days
• Field of Search: 204/294, 204/400, 73/61.1 C, 264/29.5
• US Class Current: 204/294
• CPC Class Codes: G01N 27/308 at least partially made of carbon

Abstract

An electrode for a coulometric type of electrochemical detector, comprising a formed product of a porous, graphitic carbon having the following physical properties (1), (2) and (3):

(1) an average pore diameter of 0.1 to 50 μm,

(2) a specific surface area of 10 m² /g or more, and

(3) an average interlaminar spacing (d₀₀₂) of carbon of 3.35 to 3.42 Å, as determined by X-ray diffraction analysis.

Claims

1. A process for producing an electrode for a coulometric type of electrochemical detector, which comprises molding a composition comprising carbon fibers having a specific surface area of 10 m² /g or more, a diameter of 0.01 to 2 μ

m and a length of 1 to 500 μ

m obtained by thermally decomposing a carbon source compound in the presence of a catalyst consisting of ultrafine particles of a transition metal to grow carbon in a vapor phase, a medium containing a carbonizable binder material and a pore-forming promotor and, then, sintering the thus molded product in a non-oxidizing atmosphere, said electrode comprising a formed product of a porous, graphitic carbon having the following physical properties (1), (2) and (3);

(1) an average pore diameter of 0.1 to 50 μ

m,

(2) a specific surface area of 50 m² /g or more, and

(3) an average interlaminar spacing (d₀₀₂) of carbon of 3.35 to 3.42 Å

, as determined by X-ray diffraction analysis.

2. A process as claimed in claim 1, wherein said carbon fibers have a specific surface area of 50 m² /g or more.

3. A process as claimed in claim 1, wherein said carbonizable binder material is at least one selected from the group consisting of a thermosetting resin, a thermoplastic resin, pitch and tar.

4. A process as claimed in claim 3, wherein said thermosetting resin is a phenolic resin.

5. A process as claimed in claim 1, wherein said pore-forming promotor is at least one selected from the group consisting of starch, cellulose, polyethylene oxide and polyvinyl alcohol.

9. A process as claimed in claim 1, wherein said average interlaminar spacing (d₀₀₂) of carbon is 3.35 to 3.40 Å

.

6. An analytical apparatus comprising an analytical column for liquid chromatography and at least one coulometric type of electrochemical detector,

said detector having an electrode comprising a formed product of a porous, graphitic carbon material having the following physical properties (1), (2) and (3):

(1) an average pore diameter of 0.1 to 50 μ

m,

(2) a specific surface area of 50 m² /g or more, and

(3) an average interlaminar spacing (d₀₀₂) of carbon of 3.35 to 3.42 Å

, as determined by X-ray diffraction analysis.

7. An analytical apparatus as claimed in claim 6, wherein said average pore diameter of said electrode is 1 to 30 μ

m.

8. An analytical apparatus as claimed in claim 6, wherein said average interlaminar spacing (d₀₀₂) of carbon of said electrode is 3.35 to 3.40 Å

.