Evaluation method and evaluation system of free hypohalous acid concentration

• US 6,617,168 B1
• Filed: 01/06/1999
• Issued: 09/09/2003
• Est. Priority Date: 01/08/1998
• Status: Expired due to Fees

• Current Assignee: Omega S.A. (The Swatch Group AG)
• Original Assignee: Omega S.A. (The Swatch Group AG)
• Inventors: Hanano, Yasushi, Fukutsuka, Kunihiko, Nakamura, Shinichi
• Primary Examiner(s): Warden, Jill
• Assistant Examiner(s): GAKH, YELENA G
• Application Number:
  US09/226,377
• Time in Patent Office: 1,707 Days
• Field of Search: 436/124, 436/125, 436/164, 436/166, 436/169, 436/149, 436/150, 436/2, 422/56, 422/61, 205/778.5, 205/779, 205/779.5, 205/780, 205/403.15, 204/400
• US Class Current: 436/125
• CPC Class Codes: C02F 1/76 with halogens or compounds of halogens C02F1/4674 takes precedence
• CPC Class Codes: G01N 27/4166 measuring a particular property of an electrolyte
• CPC Class Codes: Y10T 436/19 Halogen containing
• CPC Class Codes: Y10T 436/193333 In aqueous solution

Abstract

The present invention provides an evaluation method and an evaluation system of free halogen concentration which eliminate the necessity of early exchanging or recycling of catalysts, as compared with a conventional method or system. In the present evaluation method of free halogen concentration, a main flow path of a sample liquid for evaluation and a sub-region that communicates with the main flow path are formed, a potential-measuring electrode is installed in the main path, while a reference electrode is installed in the sub-region at a position where free halogen in the sample liquid has been decomposed. Moreover, free halogen in the sample liquid is decomposed by a free-halogen decomposing substance in the sub-region, and the free halogen concentration is evaluated from the electric potential difference between the reference electrode and the potential-measuring electrode.

Claims

1. An evaluation method of free hypohalous acid concentration comprising:

forming a main flow path of a sample liquid for evaluation through which the sample liquid flows and a sub-region that communicates with said main flow path for trapping sample liquid therein, said sub-region having no outlet for said trapped sample liquid during evaluation of said free hypohalous acid concentration;

decomposing free hypohalous acid in the trapped sample liquid by a free hypohalous acid decomposing substance in said sub-region;

installing a potential-measuring electrode in said main path, while installing a reference electrode in said sub-region at a position where free hypohalous acid of the trapped sample liquid has been decomposed; and

evaluating the free hypohalous acid concentration from the electric potential difference between said reference electrode and said potential-measuring electrode.

2. An evaluation system of free hypohalous acid concentration comprising:

a main flow path of a sample liquid for evaluation through which the sample liquid flows;

a sub-region that communicates with said main flow path for trapping sample liquid therein, said sub-region having no outlet for the trapped sample liquid during evaluation of said fee hypohalous acid concentration;

a potential-measuring electrode that is installed in said main flow path;

a free hypohalous acid decomposing substance which decomposes free hypohalous acid in the trapped sample liquid in said sub-region; and

a reference electrode that is installed in the sub-region at a position where the free hypohalous acid in the trapped sample liquid has been decomposed;

wherein the free hypohalous acid concentration is evaluated from the electric potential difference between said reference electrode and said potential-measuring electrode.

3. The evaluation system of free hypohalous acid concentration according to claim 2, wherein a catalyst is used as the free hypohalous acid decomposing substance.

4. The evaluation system of free hypohalous acid concentration according to claim 3, wherein the catalyst is one selected from the group consisting of activated carbon and an oxide of a metal selected from the group consisting of nickel, iron, cobalt, titanium and manganese.

5. The evaluation system of free hypohalous acid concentration according to claim 2, wherein an air-releasing means for discharging air and generated gases in the sub-region is provided.

6. The evaluation system of free hypohalous acid concentration according to claim 3, wherein an air-releasing means for discharging air and generated gases in the sub-region is provided.

7. The evaluation system of free hypohalous acid concentration according to claim 4, wherein an air-releasing means for discharging air and generated gases in the sub-region is provided.