High-purity hypochlorous acid water production equipment

Abstract

To provide an apparatus for producing high-purity hypochlorous acid water, by which pure hypochlorous acid water can be efficiently and economically produced by employing a diaphragm integrated electrode including a cathode electrode, a cation-exchange membrane, and an anode electrode.SOLUTION: In an apparatus for producing high-purity hypochlorous acid water, a cathode chamber with a cylindrical perforated structure is arranged around a cathode electrode rod at a predetermined interval, a cylindrical cation exchange membrane is installed around the cathode chamber, and an anode electrode is installed through a protective membrane, and a diaphragm integrated electrode including these in a metal frame is stored in the bath to obtain high-purity hypochlorous acid water.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an apparatus for producing high-purity hypochlorous acid water.

Background Art

[0002] Conventionally used diaphragms are physical filters with a pore size of 1 to several hundreds of micrometers. When salt water is electrolyzed, it is impossible to completely prevent mixing of acidic hypochlorous acid water on the anode side and sodium hydroxide generated on the cathode side, and the solutions are mixed to a certain extent across the membrane. Since water molecules, sodium ions and hypochlorite ions cannot be completely separated, contamination of generated hypochlorous acid water with sodium hydroxide is unavoidable.

[0003] <When a cation exchange membrane (Nafion membrane) is newly adopted as the diaphragm> Therefore, when a cation exchange membrane is newly adopted in place of conventional diaphragm methods, production of higher-purity hypochlorous acid water becomes possible. That is, the cation exchange membrane used instead of the diaphragm blocks substances other than cations, completely eliminates contamination of sodium hydroxide, and can provide high-purity hypochlorous acid water. This has the advantages of maintaining high sterilization performance and making it possible to eliminate the risk of skin roughness caused by alkali contamination.

Prior Art Literature

Patent Literature

[0004]

Patent Literature 1

Summary of the Invention

Problem to be Solved by the Invention

[0005] On the other hand, there is prior art described in Japanese Patent Publication No. 08-150325, but in this prior art, an aqueous solution for dissolving sodium hypochlorite is used as the raw material for production, and an electrodialysis cell is employed that has a first compartment where the anode is located and partitioned by a selectively permeable membrane that selectively allows cations to pass through, a second compartment where the cathode is located and partitioned by a selectively permeable membrane that selectively allows cations to pass through, and a third compartment partitioned between these two compartments, and it was not possible to obtain pure hypochlorous acid water. Therefore, the present invention aims to provide a high-purity hypochlorous acid water production apparatus that efficiently and economically produces pure hypochlorous acid water by employing a diaphragm-integrated electrode comprising a cathode electrode, a cation exchange membrane, and an anode electrode. [Means for solving the problem]

[0006] The apparatus for producing high-purity hypochlorous acid water according to this invention is characterized in that a cathode chamber having a cylindrical perforated structure is arranged at predetermined intervals around a cathode electrode rod, a cylindrical cation exchange membrane is installed around it, and an anode electrode is installed via a protective membrane, and these are housed in a metal frame to form a diaphragm-integrated electrode which is then housed in a bathtub, thereby enabling the production of high-purity hypochlorous acid water. (A diaphragm-integrated electrode consisting of a cathode electrode, a cation exchange membrane, and an anode electrode)

[0007] Furthermore, the high-purity hypochlorous acid water production apparatus of this invention is characterized in that, when the diaphragm-integrated electrode, in which the cylindrical cation exchange membrane has a check valve opening at the lower part of the cathode electrode rod and a check valve sphere is housed above the check valve opening is inserted into the bathtub, the check valve sphere floats up due to buoyancy, allowing saline solution to flow into the cathode chamber, and when the water filling is complete, the check valve sphere descends by its own weight and closes the check valve opening. (A check valve with a spherical element at the bottom of a cylindrical cation exchange membrane)

[0008] Furthermore, the apparatus for producing high-purity hypochlorous acid water according to this invention is characterized in that the cathode electrode rod is held so as to be able to move up and down within the cylindrical cation exchange membrane, and when the water injection is completed, the check valve sphere descends by its own weight to close the check valve opening, and the cathode electrode rod is lowered to close the cathode chamber. (Lower the cathode electrode rod to close the cathode chamber)

[0009] The apparatus for producing high-purity hypochlorous acid water of this invention has a protective film installed on the cylindrical cation exchange membrane made of flame-retardant Saran. (Registered trademark) It is also characterized by being made of net (a product name of Asahi Kasei Corporation). (The protective film placed on the cylindrical cation exchange membrane is made of flame-retardant Saran (Registered trademark) net)

[0010] The apparatus for producing high-purity hypochlorous acid water according to this invention is also characterized by its significant improvement in the efficiency of producing high-purity hypochlorous acid water by employing a titanium fiber sintered body as the anode electrode. Furthermore, by using an anode electrode coated with a layer of platinum or iridium dioxide on a titanium substrate, it is possible to differentiate it from conventional electrodes (plates). By atomizing chlorine gas in electrolyzed water, its residence time is increased. Therefore, the chlorine gas is more easily absorbed by the water, eliminating the loss of gas that would otherwise be released into the atmosphere. The gas is extremely toxic, and its permissible concentration is below 1 ppm.

[0011] <Method for improving the storage stability of generated high-purity hypochlorous acid water> Current products use white or transparent containers made of PP, PE, or PET, but while it is necessary to maintain an effective chlorine concentration of 50 ppm required for sterilization, self-decomposition due to light, especially ultraviolet light, limits the effective shelf life to 1-2 days. The high-purity hypochlorous acid water production apparatus of this invention solves the aforementioned problem by confirming that blocking light, especially ultraviolet light, is a major cause of decomposition, and by wrapping the storage container with aluminum foil or the like, it is possible to significantly extend the shelf life. Alternatively, it is also preferable to attach an aluminum-coated heat-shrinkable film.

[0012] <Automatic dispenser for high-purity hypochlorous acid water> The apparatus for producing high-purity hypochlorous acid water according to this invention is characterized in that the diaphragm-integrated electrode has a check valve sphere housed in the upper part of the check valve opening inside the cylindrical cation exchange membrane, and high-purity hypochlorous acid water is dripped from a photoelectric sensor through an air solenoid valve with a timer. Therefore, it does not require a high-purity hypochlorous acid water pump, resulting in a simple structure and low cost. [Effects of the Invention]

[0013] <Electrode integrated structure with diaphragm> By integrating the anode electrode, cathode electrode, and diaphragm (or ion exchange membrane), we investigated and adopted a new type of structure that is low-cost and easy to use. The novelty lies in the fact that the three components—the anode, ion exchange membrane, and cathode—are integrated into a single unit structure. Advantages: Easy to use. In other words, the generated water can be obtained simply by immersing the electrode unit in a suitable electrolytic cell container and applying electricity. In other words, it can be made more compact, and therefore its size can be reduced. Costs can be reduced. Therefore, it is possible to reduce the size of expensive components, simplify the structure, and decrease the number of parts. Furthermore, the electrode unit is easy to replace and maintain. Furthermore, in addition to batch processing, it is relatively easy to adapt it to continuous processing. Regarding the operation, the mechanism is as follows: due to the check valve at the bottom, when the electrode unit is inserted into the bathtub, the alumina spheres float up by buoyancy, and the saline solution flows into the cathode chamber. When water injection is completed, the alumina spheres fall under their own weight, closing the valve. Further, when the cathode rod is slid downward, it presses the spheres to completely enter a locked state. [BRIEF DESCRIPTION OF THE DRAWINGS]

[0014] [Figure 1] It is a schematic cross-sectional view showing an integrated diaphragm electrode constituting an apparatus for producing high-purity hypochlorous acid water. [Figure 2] It is a schematic cross-sectional view showing the entire electrolyzer incorporating an integrated diaphragm electrode constituting an apparatus for producing high-purity hypochlorous acid water. [Figure 3] It is a schematic cross-sectional view showing an automatic dispenser apparatus constituting an apparatus for producing high-purity hypochlorous acid water. [Figure 4] It shows a graph verifying the effect of light shielding by aluminum foil. [MODE FOR CARRYING OUT THE INVENTION]

[0015] Hereinafter, embodiments of the apparatus for producing high-purity hypochlorous acid water of the present invention will be described in detail. Fig. 1 is a cross-sectional view of an electrode unit 11 formed of an integrated diaphragm electrode. Fig. 2 is a cross-sectional view showing a state where the electrode unit 11 formed of an integrated diaphragm electrode is disposed in a bathtub 12. In Fig. 1 and Fig. 2, the inside of the electrode unit 11 is a cathode chamber filled with caustic soda. On the other hand, the inside of the bathtub 12 is an anode chamber filled with hypochlorous acid water. When the electrolysis timer 33 shown in Fig. 2 times out, the production of high-purity hypochlorous acid water is completed. The production amount at that time is as follows. current × time ∝ HClO production amount, that is, current × time is proportional to the production amount. When electrolysis is completed, the electrode unit 11 is pulled out, and the high-purity hypochlorous acid water in the bathtub 12 is used. The caustic soda inside the pulled-out electrode unit 11 is discarded.

[0016] More specifically, in the high-purity hypochlorous acid water production apparatus shown in Figures 1 and 2, the electrode unit 11 comprises a titanium cylindrical metal frame 21, and inside the cylindrical metal frame 21 is an anode electrode 22 made of a titanium base material coated with a layer of platinum or iridium dioxide. (Registered trademark) A protective film 23, made of a net cylinder, is positioned inside it. In the figure, 24 is a cylindrical cation exchange membrane, and a cathode chamber 25, made of a perforated acrylic cylinder, is positioned inside it. Inside the cathode chamber 25, a titanium cathode electrode rod 26 is positioned along the center of a perforated acrylic cylinder. A throttling section 27 is formed at the bottom of the cathode chamber 25, and a check valve 28 made of an alumina sphere is installed in the throttling section 27. With the check valve 28 positioned at the bottom in this manner, inserting the electrode unit 11 into the bathtub 12 causes the alumina sphere check valve 28 to float due to buoyancy, allowing saline solution to flow into the cathode chamber 25 and initiate the reaction. Once the water filling is complete, the alumina sphere check valve 28 falls due to its own weight, and the valve made of the throttling section 27 closes. Then, sliding the cathode electrode rod 26 downward causes the cathode electrode rod 26 to press down on the check valve 28, resulting in a complete lock state. After that, remove the electrode unit 11 from the bathtub 12 and use the high-purity hypochlorous acid water in the bathtub 12. The caustic soda inside the removed electrode unit 11 should be discarded.

[0017] <Methods for preserving and stabilizing the generated high-purity hypochlorous acid water> Currently, white or transparent electrode unit containers 31 made of PP, PE, or PET are used, but it is necessary to maintain an effective chlorine concentration of 50 ppm required for sterilization. However, due to self-decomposition by light, especially ultraviolet light, the effective storage period was limited to 1 to 2 days. As a solution to this problem, blocking light, especially ultraviolet light, as shown in Figure 2, is extremely effective in preventing self-decomposition, which is a cause of degradation. Therefore, it was found that wrapping the electrode unit container 31 with aluminum foil 32 or the like can significantly extend the shelf life.

[0018] <Automatic dispenser for high-purity hypochlorous acid water> As shown in Figure 3, in the high-purity hypochlorous acid water production apparatus of the present invention, hypochlorous acid water is dripped from the photoelectric sensor 41 through the air solenoid valve 42 with a timer 43. The key feature of this device is the air solenoid valve 42, followed by the drip dispensing of hypochlorous acid water using gravity. It eliminates the need for a hypochlorous acid water pump, resulting in a simple structure and low cost.

[0019] <Integrated electrode structure with diaphragm> The objectives and advantages of this invention are as follows. (a) To provide a high-performance, versatile, and inexpensive HClO (hypochlorous acid) generator. (b) By separating the electrolytic cell and electrode unit, various containers can be used as the electrolytic cell, and the production volume can be selected. This makes it possible to use it for a wide range of applications, from hand washing to vegetable use and agricultural disinfection and sterilization. Conventional products have a structure in which the electrodes are integrated into the electrolytic cell housing, so this provides an advantage in differentiation. For pesticides, it is desirable to use KCl. (c) This is a two-chamber electrolytic device equipped with a cation exchange membrane, capable of producing high-quality, high-purity hypochlorous acid water. It can be differentiated from commercially available single-chamber devices without a diaphragm. (d) By using a titanium fiber sintered body for the anode electrode, the efficiency of generating high-purity hypochlorous acid water can be significantly improved. This allows for significant differentiation from conventional electrodes (plates). (e) Chlorine gas can be atomized in electrolyzed water, increasing its residence time and making it easier for the chlorine gas to be absorbed by the water, thus eliminating the loss of gas that is unnecessarily released into the atmosphere. The amount of released gas has been reduced to an extremely small level. Note that chlorine gas is extremely toxic, and the permissible toxicity concentration is 1 ppm or less. (f) The sodium hydroxide waste liquid generated in the cathode chamber can be easily discharged by a check valve (alumina sphere) located at the bottom of the electrode.

[0020] <Improved storage performance using aluminum-coated light-shielding film. The film structure utilizes shrink film.> As mentioned above, blocking light, especially ultraviolet light, is extremely effective in preventing self-decomposition, which is a factor in decomposition. Therefore, as shown in Figure 2, it was found that the shelf life can be significantly extended by wrapping the electrode unit container 31 with aluminum foil 32 or the like. Figure 4 shows a graph verifying the effect of using aluminum foil for light shielding. In particular, the use of aluminum-coated light-shielding film and shrink film significantly improved work efficiency.

[0021] <Uses a cation exchange membrane for the diaphragm> An electrolytic diaphragm is a membrane with a mesh or network structure that has physical micropores. In contrast, cation exchange membranes are membranes that allow only cations to pass through chemically, and are used in fuel cells and the caustic soda industry. By applying this membrane to hypochlorous acid production, the generation and contamination of NaClO are suppressed, and high-purity hypochlorous acid water can be obtained.

[0022] <Principle of generating high-purity hypochlorous acid water by electrolysis> In this invention, electrolytically produced high-purity hypochlorous acid water refers to a high-purity hypochlorous acid aqueous solution with a pH of 7 or higher, produced by electrolyzing a solution of sodium chloride with a purity of 99% or higher dissolved in water in a single-chamber electrolytic cell without a diaphragm separating the anode and cathode (diaphragm-free). This electrolyzed high-purity hypochlorous acid water exists in a form where hypochlorous acid is converted into weakly bactericidal hypochlorite ions (ClO-) due to the alkali generated at the cathode. Therefore, its bactericidal activity is lower than that of acidic electrolyzed water, but because there are no restrictions on the effective chlorine concentration that can be used, it can be used at higher concentrations than other hypochlorous acid waters. High-purity hypochlorous acid water produced by electrolysis is considered equivalent to a diluted sodium hypochlorite solution and can be used as a food additive. Therefore, by neutralizing highly purified hypochlorous acid water produced by electrolysis with acid and adjusting the pH to 6.5 or below, it is possible to enhance its bactericidal power and further improve its practicality. [Industrial applicability]

[0023] In the case of high-purity hypochlorous acid water produced by electrolysis, the raw materials used are "water" and "salt," which are the most familiar substances to us. The manufacturing method is also very simple: it is produced by placing saline solution in an electrolytic cell and electrolyzing it. Therefore, it not only ensures safety during use, but also has minimal impact on the human body, the natural environment, and nutrients contained in food and ingredients, allowing you to obtain a safe and secure sterilization effect. When comparing electrolyzed high-purity hypochlorous acid water with commercially available sodium hypochlorite, electrolyzed high-purity hypochlorous acid water has drawbacks such as rapid decomposition due to residual unreacted salt and high cost due to significant wear of the electrolytic electrode. However, it is known that these drawbacks can be overcome by improving the electrode structure. [Explanation of Symbols]

[0024] 11 Electrode Units 12 Bathtubs 21. Cylindrical metal frame 22 Anode electrodes 23 Protective film 24 Cation exchange membrane 25 Cathode Chamber 26 Cathode electrode rods 27 Aperture section 28 Check valve 31 Container for electrode unit 32 Aluminum foil 33 Electrolytic Timer 41 Photoelectric Sensor 42 Air Solenoid Valve 43 Timer

Claims

1. A apparatus for producing high-purity hypochlorous acid water, characterized in that a cathode chamber having a cylindrical perforated structure is arranged at predetermined intervals around a cathode electrode rod, a cylindrical cation exchange membrane is installed around it, and an anode electrode is installed via a protective membrane, and these are housed in a metal frame to form a diaphragm-integrated electrode which is then housed in a bathtub, thereby enabling the production of high-purity hypochlorous acid water. An opening for a check valve is formed in the lower part of the cathode chamber, and a check valve sphere made of alumina sphere is installed in the opening for the check valve. A high-purity hypochlorous acid water production apparatus characterized in that, by inserting the aforementioned diaphragm-integrated electrode into a bathtub, a check valve sphere floats up due to buoyancy, allowing saline solution to flow into the cathode chamber, and when the water filling is complete, the check valve sphere descends by its own weight to close the check valve opening.

2. The apparatus for producing high-purity hypochlorous acid water according to Claim 1, characterized in that the cathode electrode rod is held so as to be able to move up and down within the cylindrical cation exchange membrane, and when the water injection is completed, the check valve sphere descends by its own weight to close the check valve opening, and the cathode electrode rod is lowered to close the cathode chamber.

3. The apparatus for producing high-purity hypochlorous acid water according to claim 1 or 2, characterized in that the protective membrane installed on the cylindrical cation exchange membrane is made of flame-retardant Saran® net (product name: Asahi Kasei Corporation).

4. The apparatus for producing high-purity hypochlorous acid water according to any one of claims 1 to 3, characterized in that a titanium fiber sintered body is used as the material for the anode electrode.

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