Electrolyzing electrode and production method of persulfuric acid-dissolving liquid by use of the electrode

Abstract

An object is to provide an electrolyzing electrode capable of electrolyzing water with a low current density to thereby produce ozone water with a high efficiency. An ozone producing electrode comprises: a substrate; and a surface layer formed on the surface of the substrate and including a dielectric material, and the surface layer is formed to have a thickness which is larger than 0 and is 2000 nm or less. Especially, the substrate is constituted of a conductive material, the dielectric material constituting the surface layer is made of a tantalum oxide or an aluminum oxide, and an electrolytic solution is electrolyzed with the low current density to thereby produce ozone with the high efficiency.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to an electrolyzing electrode for use in an industrial or household electrolysis process and a method of producing a persulfuric acid-dissolving liquid by use of the electrolyzing electrode. [0003] 2. Description of the Related Art [0004] In general, ozone is a substance having a very strong oxidizing power. There is expected broad utilization of water in which ozone has been dissolved, so-called ozone water in a cleaning and sterilizing treatment, such as application of ozone water to water supply and sewage systems or foods or application of ozone water to a cleaning treatment in a semiconductor device manufacturing process or the like. As a method of producing ozone water, there are known: a method of dissolving, in water, ozone produced by ultraviolet irradiation or electric discharge; a method of producing ozone in water by electrolysis of water and the like. [0005] In Japanese Pat...

AI Technical Summary

Benefits of technology

[0022] According to the first aspect of the present invention, the electrolyzing electrode comprises: the substrate; and the surface layer formed on the surface of the substrate and including the dielectric material, and the surface layer is formed to have a thickness which is larger than 0 and is 2000 nm or less. Therefore, when electrolysis is performed by the electrolyzing electrode, ozone can be produced efficiently at a low current density.

[0031] In consequence, when water containing the sulfate ions is electrolyzed using the electrolyzing electrode of each of the above inventions as the anode, it is possible to produce a persulfuric acid-dissolving liquid for use on the spot. Therefore, the persulfuric acid having a strong oxidizing power can easily be produced for use, which improves convenience.

Problems solved by technology

However, in the above-described ozone water producing method in which the ozone gas is produced by the ultraviolet lamp or the electric discharge system as described above to dissolve this ozone gas in water, there is required the ozone gas producing device or an operation for dissolving the ozone gas in water, and the device easily becomes complicated.

In this method, since the produced ozone gas is dissolved in water, there is a problem that it is difficult to produce ozone water having a desired concentration with a high efficiency.

However, in an electrolysis treatment using the platinum ribbon, wear on the electrode increases in accordance with electrolysis conditions.

The treatment also has a disadvantage due to mixed impurities or a disadvantage that the electrode has to be changed frequently.

However, the element has a low ozone production efficiency for the ozone producing electrode, and it is difficult to produce ozone water by a high-efficiency electrolysis method.

When ozone water is produced by the electrolysis method using such conventional ozone producing electrode, electrolysis at a high current density is required for producing ozone, and there is a problem in energy consumption or electrode life.

Moreover, in the electrode for manufacturing the persulfuric acid, in which conductive diamond is used as described above, there is a problem that production costs of the electrode itself soar, and there has been a demand for development of an electrode material capable of producing the persulfuric acid inexpensively.

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