JP2002137908A - Hydrogen peroxide generating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a miniaturized hydrogen peroxide generating apparatus. SOLUTION: In an apparatus generating hydrogen peroxide by electrifying in a cathode 10 and an anode 3, an electroconductive material 17 is installed inside of a container 1. An anode box 2, in which the anode 3 is installed, can be attached to and detached from the container 1 easily and freely. Outside of the anode box 2 in the container, the cathode 10 is installed and an oxygen containing water 6 is put. A membrane 5 is also installed at a part of the anode box 2 and between the anode 3 and the cathode 10 so as to pass current between both the electrodes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrogen peroxide generator capable of easily generating hydrogen peroxide on site.

[0002]

2. Description of the Related Art In recent years, demand for hydrogen peroxide as an industrial chemical has tended to increase. Among them, use of water treatment, waste water treatment, semiconductor substrate cleaning, and the like have attracted attention. On the other hand, utilization as a substitute for hypochlorous acid or the like as a bactericide for foods, medical products and the like is attracting attention. A major factor in the increase in demand for such a hydrogen peroxide solution is due to recent considerations for environmental pollution.In other words, even if hydrogen peroxide is decomposed, it is converted into water and oxygen, so the burden on the environment is extremely small. No. At present, in the mainstream production of anthraquinone by hydrogenation and oxidation, those having a high concentration of about 50 to 60% have been shipped so that products can be transported efficiently. Hydrogen peroxide can be dangerous at high concentrations,
Great care must be taken in storage and transport methods. However, for a user using hydrogen peroxide, it is not necessary to use a high concentration at the time of use, and it is common to dilute a high concentration according to the application. Therefore, if there is a method that can easily produce medium and low concentration hydrogen peroxide that is out of the range of dangerous substances when and where it is needed, where it is needed, it is necessary for users to handle dangerous substances. Without
It is extremely useful in terms of handling safety and convenience. As a simple method of producing hydrogen peroxide at a place of use, various methods have been proposed, such as a method in which oxygen is blown into a gas diffusion cathode and electrolytic reduction is performed to produce alkaline hydrogen peroxide. For example, Japanese Patent Publication No. 59-15990 discloses an example of a cathode composed of an anode / aqueous alkaline solution / separator / gas diffusion electrode / oxygen. Also, J. Chem. Eng. Japa of Sudoh et al.
n, Vol. 18, 409p (1985): Anode / aqueous alkaline solution / ion exchange membrane / alkaline aqueous solution / cathode composed of gas diffusion electrode /
Examples of oxygen are disclosed. As industrial applications, examples of application to pulp bleaching include JP-A-6-200389, JP-A-6-88273, and JP-A-9-176.
No. 886, and the like. Japanese Patent Application Laid-Open Nos. 9-228084 and 11-2 disclose examples of application to sterilization of cooling seawater used in chemical industry plants and power plants.
No. 29168 and the like.

[0003]

However, in any of the apparatuses, a basic or acidic aqueous solution is circulated in the positive and negative electrode chambers, and ancillary equipment other than the electrolytic apparatus, such as an electrolytic solution storage tank for an alkaline aqueous solution and a pump for sending liquid, are used. This is required separately, and the whole apparatus becomes considerably large. Therefore, in reality, it is actually installed and fixed in a certain place, and it is not designed in consideration of carrying around for home use. Also, when the anolyte discharged after the reaction is resupplied to the electrolyzer in order to use the anolyte circulating, the current over time may be reduced due to impurities contained in the replenished alkaline solution. The efficiency may be reduced, the cell voltage may be increased, and the ion exchange membrane may be deteriorated. Further, since the concentration of the basic aqueous solution requires 0.9 mol / l or more as described in JP-A-6-200389,
From an economic and environmental point of view, the basic aqueous solution discharged from the anode compartment is alkali (eg, caustic soda).
To make the alkali concentration before the electrolytic reaction. To reduce the frequency of alkali replenishment,
The amount of anolyte solution must be increased or the alkali concentration must be increased. In order to reduce the size of the apparatus, it is practical to increase the alkali concentration.However, when the concentration increases and the basicity increases, the membrane separating the anode chamber and the cathode chamber, usually an ion exchange membrane, May be deteriorated.
Therefore, the present invention has been made in view of such circumstances, and an object of the present invention is to provide a hydrogen peroxide generator capable of reducing the size of the apparatus.

[0004]

In order to achieve the above object, a hydrogen peroxide generator according to the present invention is an apparatus for generating hydrogen peroxide by energizing a cathode and an anode. An anode box in which a substance enters and the anode is disposed is detachably provided, the cathode is provided outside the anode box and oxygen-containing water is supplied, and a part of the anode box between the anode and the cathode is provided. In addition, a diaphragm is provided so that a current flows between the electrodes.

[0005] It is preferable that the anode box is provided with an opening for allowing gas in the box to flow out of the box. Preferably, the conductive material is a basic gel electrolyte or a basic solid electrolyte. A basic gel electrolyte or a basic solid electrolyte is prepared by copolymerizing acrylic acid and acrylate using a crosslinking agent to prepare polyacrylates, and removing an uncrosslinked portion of the polyacrylates, After removal, the polyacrylate is preferably thickened by a granulated water-absorbing polymer.

[0006]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a diagram showing an example of the hydrogen peroxide generator of the present invention. In FIG. 1, reference numeral 1 denotes a container, and the container 1 may be only a container main body whose upper part is opened, or may be composed of a container main body 1a and an upper lid 1b as shown in FIG. The container 1 has, for example, a rectangular parallelepiped shape or a cylindrical shape. The material of the container 1 is
It is insulative and does not deform for a long time,
For example, polyethylene, polypropylene, NBR, PV
C, Teflon (registered trademark), and a composite metal whose surface is coated with an insulating material.

In the container 1, an anode box 2 is provided detachably. As shown in FIG. 3, the anode box 2 is composed of a box body 2a and an upper lid 2b, and after the anode 3 and the like are installed in the anode box 2, the upper lid 2b
May be fixed to the box body 2a, or the upper cover 2c may be formed in a removable structure as shown in FIG. The anode box 2 has, for example, a rectangular parallelepiped shape or a cylindrical shape. In the illustrated example, a rectangular parallelepiped shape is used. As shown in FIG. 1, two handles 4 are attached to the upper part (or upper lid) of the anode box 2 so that the anode box 2 can be easily carried. The material of the anode box 2 is not particularly limited as long as it is insulative and does not corrode by the basic substance, and examples thereof include polyethylene, polypropylene, NBR, PVC, Teflon, and a composite metal whose surface is coated with an insulating substance. The anode box 2 is preferably configured so that the distance between the anode 3 and the diaphragm 5 is in the range of 0.5 to 10 cm. In addition, the anode box 2 is set to be higher than the water surface of the oxygen-containing water 6 to be put in the container 1, and in particular, it is set to be higher than the water surface by 5 cm or more so as to prevent adhesion of water to the connection terminal portion. preferable.

An anode 3 is provided in the center of the anode box 2. Since the anode 3 may contaminate the diaphragm 5 when the anode material elutes, it is preferable to use a metal which does not elute in an alkaline solution and has high resistance to an oxidation reaction. As the anode material, a material having a small overvoltage and a very small consumption compared with other metals and oxides is preferable, and thus gold, platinum, iridium, ruthenium, nickel, titanium, etc. which can be used for a long time with almost no change. Or their oxides, and their alloys, etc. can be used. Further, a metal web having a large surface area per unit area can be used. Nickel, stainless steel,
Examples include iron, copper, platinum, and alloys thereof. The shape of the anode 3 is not particularly limited, but a plate, a net, or a rod is preferably used. For example, a rectangular dimensionally stable electrode is used in the illustrated example. Specifically, as shown in FIG. 1, the anode 3 is located in the center of the anode box 2 and is arranged in parallel with two opposing side surfaces (large side surfaces) 2 d having a large area among the four side surfaces, It is attached to one end of the electrode support 7. The electrode support 7 penetrates the upper surface of the anode box 2, and a connection terminal 8 that is electrically connected to the anode 3 is provided at the other end. Electrode support 7
When the anode box 2 is installed in the container 1, the other end is formed to have a length extending to the outside of the container 1.

An opening 9 is provided in one or both of the large side surfaces 2 d of the anode box 2. The shape of the opening 9;
The size and number are not particularly limited as long as the current is set to flow sufficiently between the electrodes. The opening 9 is formed in a rectangular shape having an opening area larger than that of the anode, for example, as shown in FIG. The opening 9 is provided on both large side surfaces in the illustrated example, but may be provided on one of the large side surfaces, another side surface, or the bottom surface. That is, the opening 9
When the anode box 2 is formed in a rectangular parallelepiped shape, it can be provided on any one or more of the five surfaces excluding the upper surface.

On the side of the anode box 2 where the opening 9 is provided, a diaphragm 5 is provided so as to cover the opening 9. The diaphragm 5 allows current to flow between the anode 3 and the cathode 10 and prevents the conductive substance 17 from flowing out of the anode box 2. The diaphragm 5 has alkali resistance,
An electronically insulating and porous film can be preferably used, and specifically, a film based on an ethylene-vinyl alcohol copolymer resin film or a chlorinated ethylene polymer resin film can be used. Further, those obtained by chemically modifying the base material by adding an additive thereto are also preferably used. However,
It is preferable to set the thickness of these films to 15 to 100 microns, because when the film thickness is large, the permeation of ions becomes difficult, while when the film thickness is too small, the strength of the film itself decreases.

The method of attaching the diaphragm 5 is not particularly limited. Specifically, for example, as shown in FIG.
A rectangular box opening 2e is provided on the large side surface 2d of the frame, and a frame (box opening 2) is formed in the box opening 2e.
e), a diaphragm (a diaphragm having an area larger than the opening 11a of the frame 11) 5, a support plate (a rectangular opening whose longitudinal direction extends in the vertical direction). The portions 12a (substrate plates having a substantial number of openings 9 in the anode box) 12 (five in the example shown in FIG. 4) 12 are laminated in this order, and their edges are fixed. In the illustrated example, the frame 11, the diaphragm 5, and the support plate 1
2 are formed in substantially the same rectangular shape. This fixing method may be a bonding method or a fixing method using a fastener such as a screw. Examples of the bonding method include a heat-melting type bonding method and a method using an adhesive. Preferably, the adhesive has alkali resistance. As a fixing method using a stopper, for example, as shown in FIG. 6, there is a method of attaching the frame 11, the diaphragm 5, and the support plate 13 with screws 14. Specifically, a plurality of screw holes 2f are provided in the periphery of the box opening 2e on the large side surface 2d of the anode box 2. Frame 1
1, the diaphragm 5, and the support plate 13 are each formed in substantially the same rectangular shape, that is, a rectangular shape having a size including the screw hole 2f of the anode box 2. The frame 11 has an opening 11a substantially the same size as the box opening 2e, and a plurality of holes 11b through which the screws 14 pass at the same positions as the screw holes 2f. In the diaphragm 5,
A plurality of holes 5a through which the screws 14 pass are provided at the same positions as the screw holes 2f. The support plate 13 has the screw hole 2f
A plurality of holes 13b through which screws 14 pass are provided at the same positions as above, and four circular openings 13a, which are substantially openings 9 of the anode box 2, are arranged side by side in the upper, lower, left and right directions. The frame 11, the diaphragm 5 and the support plate 13 are sequentially laminated on the large side surface 2 d of the anode box 2 in accordance with the position of the screw hole 2 f, and after lamination, these members are fixed to the anode box 2 by screws 14.

As another method for fixing the diaphragm 5, as shown in FIG. 7, the shape of the internal space of the container body 2a is substantially the same as that of the container body 2a (a bag shape with an open top) and the upper part of the box is To form a film-like diaphragm having four pieces covering the film.
The bag-shaped diaphragm can be formed by, for example, a heat sealing method so as to approximate the shape of the internal space of the container body 2a. The formed bag-shaped diaphragm is inserted into the container body 2a, and four pieces are bent outward. Next, the upper lid 2c to which the anode 3 is attached is attached to the container body 2a so as to sandwich the four pieces. After the mounting, the upper lid 2c is fixed to the main body 2a by sealing the periphery thereof with a heat seal, an adhesive, or a seal tape. Also in this case, the diaphragm can be attached.

When the anode box is not used, since the diaphragm 5 is exposed, the barrier 5 (opening 9) is covered with a barrier sheet made of aluminum foil or the like, and its peripheral portion is covered with, for example, an adhesive or the like. The membrane 5 may be hermetically sealed by heat sealing or the like to prevent breakage of the diaphragm 5.

Upper surface of anode box 2 (top lids 2b, 2c)
As shown in FIG. 1, an opening 15 is provided for allowing the gas in the box 2 to flow out of the box. The size, shape, and number of the opening portions 15 are set so that water that has entered and that has naturally evaporated at room temperature can flow out of the box. Further, the opening 15 is not limited to the upper surface, and may be provided on the side surface. The opening portion 15
Since it is sufficient that the device is opened only when the device is driven, the device may be formed in an openable and closable structure when the device is not driven. Further, when not driven, the opening 15 may be sealed by attaching a lid such as a cap to the opening 15 or a barrier sheet made of aluminum foil or the like may be placed on the opening 15 and the peripheral portion thereof may be made of, for example, an adhesive or heat seal. Alternatively, the periphery of the opening 15 may be hermetically sealed. When a barrier sheet is used, it is preferable to set the anode box 2 in the container 1 and then peel off the barrier sheet.

In the anode box 2, the conductive material 1 is arranged so that the upper surface is located above the opening 9 and below the opening 15.
7 is inserted. The conductive substance 17 is a substance containing hydroxyl ions, and for example, an alkaline aqueous solution in which a basic inorganic compound such as sodium hydroxide or potassium hydroxide is dissolved in water can be used. The concentration of these basic inorganic compounds is not particularly limited as long as no precipitation is caused by long-term energization, but is preferably 5 to 50% by weight, more preferably 1 to 50% by weight.
0 to 40% by weight. If the alkaline aqueous solution leaks out of the anode box 2 due to some obstacle, it may not only contaminate the surroundings but also be harmful to the human body. It is preferable to make the shape. That is, the conductive substance 17
Is preferably a basic gel electrolyte or a basic solid electrolyte.

The thickener is not particularly limited as long as it can gel an aqueous alkaline solution. For example, polyacrylic acid is obtained by copolymerizing solid acrylic acid and acrylate in an aqueous solution using a crosslinking agent. Is prepared, the polyacrylate is finely divided, the polyacrylate is immersed in a mixed solvent of water and a water-soluble solvent to dissolve and remove the uncrosslinked portion of the polyacrylate, and after removal, A water-absorbing polymer or the like obtained by drying and pulverizing the polyacrylic acid salts into granules can be used. As the thickener, it is preferable to use a water-absorbing polymer because the gel electrolyte is not deteriorated even when used for a long period of time and is not affected electrically. Regarding the method of gelling the alkaline aqueous solution with the thickener,
There is no particular limitation as long as the thickener can be uniformly dispersed in the alkaline aqueous solution.However, it takes a very long time to uniformly disperse the thickener after the alkaline aqueous solution is prepared. It is preferable to take a method of uniformly mixing a solid alkali and then adding water while stirring. The stirrer used for stirring is not particularly limited, for example, a magnet motor type stirrer may be used, or a stirrer such as a homomixer or a hibis mix suitable for dispersion of a high-viscosity substance may be used. good.
Since the amount of the thickener to be added is appropriately determined according to the type of the thickener, it cannot be said unconditionally, but is 5 to 30% by weight based on the alkali aqueous solution. Also, increase the amount of the thickener added, for example, 30 to 50% by weight based on the aqueous alkali solution.
Then, since the gel state is changed to a solid state, the amount of the thickener added may be increased to use an aqueous alkali solution as the basic solid electrolyte.

The anode box 2 is provided at a predetermined position in the container 1. As a means for arranging the anode box 2, any means may be used as long as it can be positioned at the same position even when the anode box 2 is replaced. Guide piece 1
8 may be provided so that the anode box 2 is located at a predetermined position on the bottom surface of the container 1. Further, the anode box 2 may be detachably attached to an inner wall or the like of the container 1 by a fastener or the like.

A cathode 10 is provided inside the container 1 and outside the anode box 2. As the cathode 10,
There is no particular limitation as long as it can be applied to on-site hydrogen peroxide production, and examples thereof include graphite felt, graphite, carbon fiber materials, and porous amorphous carbon molded products. Examples of graphite include those obtained by extruding and firing coke and those obtained by molding. Examples of the carbon fiber material include a knitted carbon fiber, and examples of the knitted carbon fiber include a commercially available CF cloth. Carbon fiber materials other than CF cloth may be used. Glassy carbon (glassy carbon) can be exemplified as a porous amorphous carbon molded body.

Further, an organic compound producing hydrogen peroxide may be carried on the electrode to form a cathode. For example,
It is known that when electricity is supplied using a cathode containing a redox compound or a redox resin (Q), the following reaction occurs repeatedly to generate hydrogen peroxide (for example, see Japanese Patent Application Laid-Open No. 61-284591). No.). Q + nH ⁺ + ne ⁻ → H _n Q (3) H _n Q + (n / 2) O ₂ → Q + (n / 2) H ₂ O ₂ (4) As the organic compound having a redox ability, For example, benzoquinone, naphthoquinone, anthraquinone, a derivative thereof, and the like can be given. Specific examples of the derivatives include methoxybenzoquinone, 2-tert-butylbenzoquinone, 2,5-diphenylbenzoquinone, 2,6
-Dimethylbenzoquinone, 2,6-di-tert-butylbenzoquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-nitroanthraquinone, 1- (or 2-) chloroanthraquinone, 1,5 -(Or 1,4- or 1,8
-) Dichloroanthraquinone and the like. Examples of the redox resin include a quinone-based redox resin, polyaniline, and the like. As an electrode supporting a quinone-based redox resin, a hydroquinone-formaldehyde condensed resin (Manecke, Z. Elek) is used as a benzoquinone-based resin.
trochem., 57 , 189 (1953)) and hydroquinone- (diazotized poly-p-aminostyrene) condensation resin (Rao et al., Chem. I.
(London), 145 (1961)), and anthraquinone-based resins include 2-formylanthraquinone-polyvinyl alcohol condensed resin (Izoret et al., Ann. Chim., 254 , 671 (1962)) and the like, but are not limited thereto. It is not done. In order to carry these compounds or resins on the electrode, a method of dissolving or dispersing in methanol, isopropyl alcohol, acetone, a halogen solvent or the like, then immersing the supporting substrate in the solution, pulling it up, and air-drying, or spraying the solution is used. Means for applying to the supporting substrate by a method or the like is used. The support substrate is not particularly limited as long as it is conductive, and a carbon electrode such as graphite felt, CF cloth, and graphite, and a metal electrode such as titanium platinum and copper mesh are used. These support substrates may be surface-treated with a silane-based or titanium-based coupling agent or the like in order to increase the adsorptivity of the organic compound.

Further, similarly, conductive polyaniline (PA)
It is also known that when electricity is carried on a cathode electrode, the following reaction proceeds in a cycle to generate hydrogen peroxide (K. Morita et.al, Chem. Lett., 1996, p61).
5, or ibid, vol. 15, No. 5 (1997)). ^{PA + nH + + ne - →} H n PA (5) H n PA + (n / 2) O 2 → PA + (n / 2) H 2 O 2 (6) conductive polymer polyaniline loaded with electrodes, The method of supporting directly on the electrode surface by electrolytic polymerization (material technology,
vol.15, No.5, p165 (1997)), but as another means, a commercially available polyaniline dispersion solution (ORMECON ^™ D manufactured by ORMECON) may be used.
ispersion 900132), immerse the support substrate and pull it up.
It can also be produced by air drying or by applying the solution to a supporting substrate by a spray method or the like. The support substrate is not particularly limited as long as it is conductive, and a carbon electrode such as graphite, CF cloth, graphite, or a metal electrode such as titanium platinum or copper mesh is used. These support substrates may be surface-treated with a silane-based or titanium-based coupling agent or the like in order to increase the adsorptivity of the organic compound.

The cathode 10 is for generating hydrogen peroxide, and the larger the surface area, the greater the amount of hydrogen peroxide generated. Therefore, the larger the surface area, the better. When the area of the diaphragm 5 (the opening 9 of the anode box 2) is too small, the current value is remarkably reduced, and when the area is too large, the durability of the device is reduced.
0-20 / 10, more preferably 5 / 10-10 / 10
It is. The area ratio of the anode 3 to the cathode 10 is not particularly limited as long as the current value does not extremely decrease, and may be small. The shape of the cathode 10 is not particularly limited, but a plate-like, net-like or rod-like shape is preferably used. For example, a rectangular dimensionally stable electrode is used in the illustrated example. Specifically, the large side surface 2d of the anode box 2
And is arranged so as to cover the opening 9.

The mounting position of the cathode 10, that is, the distance from the anode 3 is preferably 1 to 20 cm, more preferably 1 to 10 cm, since the current value decreases if it is too long. The cathode 10 may be attached to the inner wall of the container 1 or may be attached to the anode box 2. When the cathode 10 is attached to the container 1, for example, the cathode 10 may be supported at a lower end of a support 19 provided along the vertical direction of the container 1. The support 19 is attached to the upper surface of the container 1, has an upper end extending outside the container 1, and has a connection terminal 20 connected to the cathode 10 at the upper end. Further, the cathode 10 may be attached to the inner wall of the container 1 by a bonding method or using a stopper 21 such as a screw as shown in FIG. Also in this case, the cathode is attached to one end (lower end) of the support 19 provided with the connection terminal 20 at the other end (upper end).

When the cathode 10 is attached to the anode box 2, the cathode 10 may be attached to the outer wall of the box 2 by a bonding method or by using a stopper 22 such as a screw as shown in FIG. Further, as shown in FIGS. 9 and 10, for example, the plate-shaped cathode 10 may be attached to the outer wall of the box 2 via a spacer 23 having a predetermined length. As the spacer 23, a rod-shaped resin that is insulative and is not eroded by a basic substance, for example, a resin molded from a resin such as polyethylene, polypropylene, NBR, PVC, or Teflon is used. As for the length of the spacer 23, the length between the cathode and the anode is 1 to 20 cm, more preferably 1 to 1 cm.
Set to 0 cm. Spacer 2
Although the number and mounting position of 3 are not particularly limited, for example,
There are four in total, one each near the four corners of the rectangular cathode. You may make it provide in other places other than these four places. The attachment of the cathode 10 and the spacer 23 and the attachment of the spacer 23 and the anode box 2 may be performed by bonding, or may be performed using a fixing tool such as a screw. For example,
As shown in FIGS. 9 and 10, when the screws 24 are used, holes through which the screws 24 pass are provided near the four corners of the rectangular cathode 10, and holes through which the screws 24 pass are also provided in the spacer 23. The anode box 2 is provided with a screw hole at a corresponding position where the screw 24 is screwed. With this configuration, the cathode 10 is superimposed on the anode box 2 via the spacer 23 at the position of the screw hole, and the cathode 1 is
By fixing 0 to the box 2, the anode box 2 in which the cathode 10 is integrated is obtained. A support 19 is mounted on the cathode 10 in the same manner as described above.

When the hydrogen peroxide generator of the present invention is driven for a long period of time, if the cathode 10 is formed of graphite felt or the like, the fibers may gradually fall off and float in the container 1. For this reason, in order to prevent the fiber from falling off, as shown in FIG.
5 may be applied. As the chemical fiber 25, a fiber which does not deteriorate by reacting with hydrogen peroxide is used, and a non-woven cloth having a surface formed of a paraffin-based polymer is preferably used. The size of the hole of the non-woven cloth to be used does not need to be a fixed size, but if it is too small, it becomes difficult for current to flow. Therefore, it is preferably in the range of 10 to 50 g / m ² , more preferably 30 to 50 g / m ^2. It is in the range of 40 g / m ² .

In the container 1, as shown in FIG. 1, the upper surface is located above the opening 9 of the anode box 2 and below the opening 15, for example, at a position 26 in the illustrated example. Up to this, oxygen-containing water 6 is introduced. The oxygen-containing water 6 is not particularly limited as long as the amount of dissolved oxygen is 3 mg / L or more, and includes tap water, well water, distilled water, ion-exchanged water,
Physiological saline, seawater and the like are preferably used.

In the vicinity of the bottom of the vessel 1, there is provided an air blowing section 28 for blowing air from the air supply pipe 27 into the vessel 1 for both supplying oxygen used for the reaction and stirring the liquid. ing. The position and number of the air ejection portions 28 are not particularly limited, but are arbitrary as long as DO (Dissolved oxygen) in the liquid does not decrease, oxygen-containing water is uniformly stirred, and the current value does not decrease. Is decided. Alternatively, a commercially available air diffuser 29 made of ceramics may be installed in the container (attached to the air blowing unit 28) to blow air. Air diffuser 29 (air ejection part 2)
The liquid is stirred by the air from 8), but the liquid may be stirred by other stirring means instead of air, for example, by circulating oxygen-containing water or installing a stirring blade in the vessel. . However, in this case, the DO in the liquid is preferably maintained at 10 to 100%, particularly preferably at 50% or more. If DO is too low, not only the current value will decrease, but also the amount of hydrogen peroxide generated will decrease significantly. For example,
In the case of circulating the oxygen-containing water 6, as shown in FIG.
1 and a circulating pump 32 constituted by a magnet pump, for example, and water from the circulating pump 32 is supplied from two sprinkling ports 33 near the upper part of the container 1 to the container 1 respectively.
The conduit 34 may be connected to the sprinkler port 33 so as to squirt into the inside. Thus, the anode box 2 is placed in the container 1.
The suction port 30 and the water sprinkling port 33
Is attached, water can be stirred between the two cathodes 10 and the respective diaphragms 5.

The cathode 10 and the anode 3 are connected to each of the connection terminals 2.
It is connected to a constant voltage DC power supply 42 (see FIG. 13) via 0 and 8 so as to be energized. DC power supply 42
Is 1.0-30.0 V, preferably 1.5-1
5.0 V can be applied. The current supply to the cathode 10 and the anode 3 may be continuous or intermittent, but is preferably continuous in order to prevent organic substances from adhering to the electrode surface. In addition, in order to remove dirt generated on the electrodes and diaphragm surface during operation,
A device for automatically reversing the voltage between the anode and the cathode for a certain period of time may be provided. The set time at that time is, for example, 5 minutes every 24 hours. Further, it is preferable that the temperature of the anode electrolyte is not set high in consideration of heat generated by electrolysis. Further, since the temperature of the oxygen-containing water 6 contains hydrogen peroxide, it is preferable to control the temperature to be 40 ° C. or lower. vice versa,
If the temperature is low, the current value decreases, and the amount of generated hydrogen peroxide also decreases. Therefore, a heater with temperature control may be installed in the hydrogen peroxide storage tank, that is, the container.

Next, the case where hydrogen peroxide is generated using the hydrogen peroxide generator of the present invention will be described. First, while attaching the anode 3 and the diaphragm 5 to the anode box 2,
The conductive substance 17 is put in the box. The anode box 2 is installed at a predetermined position of the container 1 to which the cathode 10 is attached, and after the installation, for example, tap water is put into the container. Then, electricity is supplied to the anode 3 and the cathode 10 while blowing air from the air diffuser 29. Electric current flows between the anode 3 and the cathode 10 through the diaphragm 5 to perform electrolysis. That is, inside the anode box 2, hydroxyl ions present in the conductive substance 17 are consumed, and the following reaction (1) in which oxygen gas is generated proceeds, and outside the anode box 2, the following formula (1) The hydrogen peroxide ion generation reaction represented by 2) occurs, and hydrogen peroxide is generated. ^{_{4OH - → O 2 + 2H 2}} O + 4e - (1) O 2 + H 2 O + 2e - → HO 2 - + OH - (2)

As described above, the hydrogen peroxide generator of the present invention can generate hydrogen peroxide by using the detachable anode box 2, so that the storage tank for storing the conductive substance 17 and the delivery of the conductive substance 17 are provided. A liquid pump or the like is not required, and the size of the apparatus can be reduced. Also, by using a basic aqueous solution such as sodium hydroxide or potassium hydroxide as the conductive substance 17, the conductive substance 17 contains a large amount of hydroxyl ions,
The positive cathode reaction can be performed efficiently. Further, in order to make the replacement frequency of the anode box 2 as long as possible, the basic substance is prepared at a high concentration. Since there is a danger that the conductive substance 17 is gelled by adding an appropriate gelling agent, there is no need to worry about liquid leakage or the like. In addition, by providing the anode box 2 with the opening 15, when a high concentration of a basic electrolyte is immersed in water through the diaphragm 5, water may enter the basic side due to osmotic pressure during long-term use. However, since the invading water evaporates and goes out of the box 2 through the opening 15, the inside of the anode box 2 is not filled with water.

As shown in FIG. 13, the hydrogen peroxide generator of the present invention has a first electromagnetic valve 35 and a pump 36 at the top of the vessel 1 and a water pipe 38 connected to a water tank 37.
And the second on the bottom of the container 1
The pipe 40 having the electromagnetic valve 39 may be connected and configured. The first and second solenoid valves 35 and 39 and the pump 36 are controlled by a control circuit 41. Control circuit 41
Stores oxygen-containing water 6 such as tap water in a water tank 37 in a container 1
The first and second solenoid valves 35 and 39 and the pump 36 are controlled so that a predetermined amount is introduced into the inside and the hydrogen peroxide solution in the container 1 is discharged. For example, the control circuit 41 controls the container 1
When the inside is empty, the first solenoid valve 35 is opened and the pump 36 is driven with the second solenoid valve 39 closed,
A specific amount of oxygen-containing water 6 such as tap water in the water tank 37 is guided into the container 1. After a predetermined amount of the oxygen-containing water 6 has accumulated in the container 1, the pump 36 is stopped and the first solenoid valve 35 is closed. Then, after generating hydrogen peroxide in the container 1, the second electromagnetic valve 39 is opened to discharge the hydrogen peroxide solution in the container 1. When the discharge of hydrogen peroxide solution is completed,
At the same time or immediately after closing the second solenoid valve 39, the first solenoid valve 3
5 is opened, and the pump 36 is driven to introduce the oxygen-containing water 6 into the container 1 in the same manner as described above, so that these operations are continuously performed. At this time, in order to introduce a predetermined amount of the oxygen-containing water 6 to the container 1, the same amount of the oxygen-containing water 6 may be introduced into the container 1 while keeping the drive time of the pump 36 constant, or the inside of the container 1 may be introduced. The driving of the pump 36 may be stopped when the water level reaches a predetermined water level measured by a sensor or the like. The discharge of the hydrogen peroxide solution may be performed by opening the second solenoid valve 39 after a predetermined time has elapsed after the introduction of the oxygen-containing water, or the concentration of the hydrogen peroxide in the water in the container 1 may be reduced to a predetermined value. , The second electromagnetic valve 39 may be opened. The energization of the electrodes 3 and 10 and the stirring by air may be performed only when oxygen-containing water is accumulated in the container 1, or may be constantly operated. By configuring the hydrogen peroxide water generator in this way, it is possible to continuously produce hydrogen peroxide water.

[0031]

The following examples further illustrate the present invention.
Although described concretely, the present invention is not limited to these.
Not. (Example 1)Fabrication of anode box The size shown in FIG. 1 is 250 × 250 × 50 mm.
In the pole box 2, a nickel plate (100 mm
Square, plate thickness 0.5 mm), polyethylene
Rivinyl alcohol copolymer film (Eva
EF-F-15 "). In addition,
The opening area of the anode box 2 is 250 cm ^Two(Double-sided alignment
500cm^Two) And the surface of the anode 3
The distance between the diaphragm and the diaphragm 5 is set to be 25 mm.
Was. 1 mol / L sodium hydroxide
Lithium aqueous solution and cross-linked polyacrylic acid (Japan Pure Chemicals
2% by weight of “Junlon PW-50”)
The gel electrolyte prepared by the
Filled to about a percentage.

Preparation of cathode (1) A CF cloth was immersed in a 5% solution of acetone in 2-ethylanthraquinone for 2 minutes, and then slowly pulled up.
Dried. From the weight change before and after immersion, about 4% by weight of 2
It was confirmed that -ethylanthraquinone was supported, and this was designated as electrode Q-1. (2) According to the literature of Izoret, 2
-Redox polyvinyl acetal synthesized by the action of formyl anthraquinone was dissolved in DMSO at 5%. After immersing the CF cloth in this solution for 2 minutes, it was slowly pulled up and dried under reduced pressure. Based on the weight change before and after the immersion, about 5% by weight of the polymer was assumed to be supported, and this was designated as electrode Q-2. (3) Polyaniline was electrolytically polymerized on the CF cloth. From the weight change before and after the electrolytic polymerization, it was determined that about 0.8% by weight of polyaniline was supported, and this was designated as electrode A-1. (4) Untreated graphite felt ("GF-20" manufactured by Nippon Carbon Co., Ltd.) is entirely covered with a polyethylene nonwoven fabric ("Elves S0153WDO" manufactured by Unitika Ltd.), and the periphery is bonded with a hot melt adhesive. This was designated as electrode G-1. In addition, all the cathodes were produced in a 220 × 200 mm rectangular shape.

Next, the prepared anode box 2 is placed at a predetermined position in a container 1 having a shape as shown in FIG.
Various containers 1 were prepared in which two kinds of cathodes 10 of Q-1, Q-2, A-1, and G-1 were respectively mounted in the containers. In addition, the diaphragm 5 of the anode box 2 and the cathode 1
0 All distances on the surface are set to be 30 mm.
2 liters of tap water was filled thereinto, and air was spouted from the air diffuser 29 at a flow rate of 1 liter per minute. Then, the anode 3 of each container 1 and the two cathodes 10 were connected, and 1.5 V was applied by a DC power supply 42 to perform electrolysis. The energy efficiency was determined by connecting a coulomb meter 43 to a DC power supply 42 as shown in FIG. Table 1 shows the results obtained when energization was performed continuously for 24 hours. Further, the current value at that time gradually increased with the leakage of NaOH from the anode 3.

[0034]

[Table 1]

As is clear from the results shown in Table 1, Q-
Each of the devices using various cathodes of 1, Q-2, A-1, and G-1 has high energy efficiency exceeding 60% and high efficiency. FIG. 14 shows changes in the current value, the amount of hydrogen peroxide, and the amount of NaOH when the electrode G-1 was used. From the results shown in FIG. 14, it can be seen that the NaOH concentration in the cathode chamber gradually increases with time, the current value increases accordingly, and the hydrogen peroxide concentration also gradually increases.

(Example 2) Next, similarly to Example 1, the container 1 in which the anode box 2 was installed was constructed as shown in FIG. 13 and was continuously operated under the following conditions. The dimensions and the like of the anode box are shown below. Anode box dimensions: 250 × 250 × 50 mm Anode: Nickel plate (100 mm square, plate thickness 0.5 mm) Installed at the center of the anode box Diaphragm: Polyethylene-polyvinyl alcohol copolymer (“EVAL E” manufactured by Kuraray Co., Ltd.)
The opening area of the F-F-15 ") anode box: 250 cm ² (500 cm ² in conjunction both sides) the distance between the anode surface and the membrane: 25mm anode box: 3 mol / L crosslinked polyacrylate sodium hydroxide solution ( A gel electrolyte prepared by uniformly dispersing 1.5% by weight of "Junron PW-50" manufactured by Nippon Pure Chemical Co., Ltd. (filled up to about 80% of the inner volume of the anode box) Cathode: G-1 (220 × 200 mm, (Thickness: 7 mm) Distance between diaphragm and cathode surface: 30 mm Oxygen-containing water: tap water (2.4 liters) Air ejection volume: 2 liters / minute (always running) Power supply: 1.5 V DC power supply (always running) Solenoid valve: Closed for 23 hours and 55 minutes, repeated open for 5 minutes (opens hydrogen peroxide solution in the container completely when opened for 5 minutes) Second solenoid valve and pump: Closes after opening first solenoid valve for 5 minutes La That when by driving the pump while the second solenoid valve to open at the same time, the tap water was 2.4 liters fed into the container,
After the supply, the second solenoid valve is closed and the driving of the pump is stopped. In order to experimentally obtain energy efficiency, a coulomb meter was connected to the power supply device. During continuous operation under these conditions, the hydrogen peroxide concentration and the energy efficiency of the water discharged from the container were plotted on the same graph as shown in FIG. From the results shown in FIG. 15, it was confirmed that the performance of the hydrogen peroxide generator of the present invention was stable. The energy efficiency was determined by the following equation. Energy efficiency (%) = (number of generated H ₂ O ₂ moles × 2)
× 100 / (coulomb amount / 96500)

[0037]

According to the present invention, the size of the apparatus can be reduced.

[Brief description of the drawings]

FIG. 1 is a view showing an example of a hydrogen peroxide generator according to the present invention, wherein (a) is a top view thereof, and (b) is AA of (a).
FIG. 3C is a sectional view taken along line BB of FIG.

FIG. 2 is a sectional view showing another example of the hydrogen peroxide generator of the present invention.

FIG. 3 is a view showing an example of the anode box of the present invention;
(A) is a top view, (b) is a front view, and (c) is a side view.

FIG. 4 is a view showing another example of the anode box of the present invention;
(A) is a top view, (b) is a front view, and (c) is a side view.

FIG. 5 is a view showing another example of the anode box of the present invention.

FIG. 6 is a view showing another example of the anode box of the present invention.

FIG. 7 is a view showing another example of the anode box of the present invention.

FIG. 8 is a view showing another example of the anode box of the present invention;
(A) is the front view, (b) is a side view.

FIG. 9 is a view showing another example of the anode box of the present invention;
(A) is the front view, (b) is a side view.

FIG. 10 is a view showing another example of the anode box of the present invention.

11A and 11B are diagrams showing an example of the cathode of the present invention, wherein FIG. 11A is a front view and FIG. 11B is a side view.

FIG. 12 is a view showing another example of the hydrogen peroxide generator of the present invention, wherein (a) is a front view and (b) is a side view.

FIG. 13 is a schematic configuration diagram showing another example of the hydrogen peroxide generator of the present invention.

FIG. 14 is a diagram showing a relationship between time and current.

FIG. 15 is a diagram showing the relationship between the number of days and the amount of generated hydrogen peroxide.

[Explanation of symbols] [Selection diagram]

 DESCRIPTION OF SYMBOLS 1 Container 2 Anode box 3 Anode 5 Diaphragm 6 Oxygen-containing water 10 Cathode 17 Conductive substance

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshiyuki Shimo 8 Chidori-cho, Naka-ku, Yokohama-ku, Kanagawa Prefecture Inside of the Central Research Laboratory, Nishiishi Mitsui Co., Ltd. (72) Inventor Mino Mizuta 8 Chidori-cho, Naka-ku, Yokohama-shi, Kanagawa Address: Nishiishi Mitsubishi Co., Ltd.

Claims (4)

[Claims] 1. An apparatus for generating hydrogen peroxide by energizing a cathode and an anode, wherein an anode box in which a conductive substance enters and the anode is disposed is provided detachably in a container. Hydrogen peroxide, wherein the cathode is provided and oxygen-containing water is provided outside the anode, and a diaphragm is provided in a part of the anode box between the anode and the cathode so that current flows between the electrodes. Generator. 2. The hydrogen peroxide generator according to claim 1, wherein the anode box is provided with an opening for allowing gas in the box to flow out. 3. The hydrogen peroxide generator according to claim 1, wherein the conductive substance is a basic gel electrolyte or a basic solid electrolyte. 4. A basic gel electrolyte or a basic solid electrolyte is prepared by copolymerizing acrylic acid and acrylate using a cross-linking agent to prepare polyacrylates. 4. The hydrogen peroxide generator according to claim 3, wherein the polyacrylic acid salt is thickened by a granulated water-absorbing polymer after removing the part and removing the part.