JPH1066976A - Reforming method of water and reforming device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently reform water by adding a weak acid and its salt to the water at the time of reforming the water by impressing voltage between plural electrodes arranged in the water top lower the oxidation-reduction voltage of an oxidation-reduction reaction system contained in the water. SOLUTION: The water 15 such as city water is fed to an electrolytic cell 16 to be stored and the weak acid and its salt are added. As a result, an acidic buffer aq. solution high in electric conductivity and small in the change of pH is prepared to enable to make the pH constant by the buffering action even at the time of impressing voltage between the electrodes 1, 2. Then, since a larger number of hydrogen ions than other various ions contained in the water exists, the electrode reaction due to the water is accelerated and H2 is mainly generated in the water, the generation of O2 is suppressed and a reducing material contained in the water is increased. Then the oxidation- reduction voltage of the oxidation-reduction reaction system in the whole water 15 is remarkably lowered and the water having high reductively is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water reforming method for reforming water such as tap water into water suitable for eating and drinking or for facial cleansing, and a water reforming apparatus used for the same. is there.

[0002]

2. Description of the Related Art Heretofore, an oxidation-reduction reaction system contained in water, for example, H ₂ O / O ₂ , O ₂ / O ₃ , has been applied by applying a voltage between electrodes arranged in water such as tap water. , H ⁺
Water is reformed by lowering the oxidation-reduction potential of / H ₂ or the like. For example, JP-A-4-225892
In Japanese Unexamined Patent Application Publication No. 5-26189, first and second electrodes are arranged in water, and an alternating voltage or a direct current voltage is applied between the first and second electrodes while periodically switching the polarity. A method for reforming water is described.

In this method, an electrochemical reaction, that is, an oxidation-reduction reaction is caused to water and a substance contained (dissolved) in the water on the first and second electrodes, so that the water and the water are converted. The oxidation-reduction potential of the oxidation-reduction reaction system composed of the contained substances is reduced. The reformed water thus obtained has a reducing property, and for example, sludge does not easily adhere to the pipe, the smell such as chlorine is eliminated, the pipe becomes delicious, the pipe does not corrode, and red water is suppressed. It is effective in preventing food from corroding.

[0004]

However, in the above-mentioned conventional method, various ions contained in water, such as negative ions such as chlorine, hypochlorous acid, fluorine and sulfuric acid, and potassium,
Positive ions such as sodium and iron have a great effect on the oxidation-reduction reaction on the electrode. Electric energy may be used for the reaction on the electrode not involved in the oxidation-reduction potential, and the voltage to be applied must be changed according to the quality of the water before reforming. Water cannot be reformed, and water having a low ionic strength has a problem that water does not easily flow into the water, and it takes time to reform the water, so that water cannot be reformed efficiently. In addition, there is a problem that the pH of the water after the reforming is not always constant due to the pH of the water before the reforming. In particular, when the water before the reforming is alkaline (pH> 7), the pH of the water after the reforming tends to further increase, and the reformed acidic (acid region) water cannot be obtained. Was.

[0005] The present invention has been made in view of the above points, and provides a water reforming method capable of efficiently reforming water and obtaining water having an acidic and high reducing property. An object of the present invention is to provide a water reforming apparatus used in the water reforming method.

[0006]

According to a first aspect of the present invention, there is provided a method for reforming water, wherein the water is contained in the water by applying a voltage between a plurality of electrodes disposed in the water. In reforming water by lowering the oxidation-reduction potential of the oxidation-reduction reaction system, a weak acid and a salt thereof are added to water 15.

[0007] The water reforming method according to claim 2 of the present invention is characterized in that, in addition to the constitution of claim 1, the weak acid has an ionization constant of 10 ^-5 or more. . The method for reforming water according to claim 3 of the present invention is characterized in that, in addition to the constitution of claim 1 or 2, the weak acid and its salt are citric acid and its salt. Further, in the water reforming method according to claim 4 of the present invention, in addition to the constitution of any of claims 1 to 3, the pH of water 15 is adjusted to 4 by adding a weak acid and a salt thereof to water 15. It is characterized in that it is adjusted to 0.5 to 6.5.

According to a fifth aspect of the present invention, there is provided a method for reforming water according to any one of the first to fourth aspects, wherein a solution containing the weak acid and a salt thereof is added to the water 15. It is a feature. The water reforming method according to a sixth aspect of the present invention is characterized in that, in addition to any one of the first to fifth aspects, sodium ascorbate is further added to the water 15. .

A water reforming apparatus according to a seventh aspect of the present invention comprises an electrolytic cell 16 for storing water 15 to which a weak acid and a salt thereof are added, and a water reforming apparatus for storing the water 15 stored in the electrolytic cell 16. It is characterized by comprising a plurality of electrodes 1 to 10 arranged therein and a power supply 17 for applying a voltage between the electrodes 1 to 10.

[0010]

Embodiments of the present invention will be described below. FIG. 1 shows an embodiment of a water reforming apparatus. Reference numerals 1 and 2 denote electrodes formed of a metal flat plate or the like, which are erected on the bottom surface of the electrolytic cell 16 so as to face each other. The electrodes 1 and 2 are preferably insoluble electrodes formed by using a metal material such as Pt, and can be formed by, for example, a Ti-Pt plated product, a Ti-Pt.Ir plated product, or a fired product.

The electrodes 1 and 2 are electrically connected to a power supply 17 by wirings 18 and 19, respectively.
Thus, a voltage can be applied between the electrodes 1 and 2. The voltage to be applied between the electrodes 1 and 2 may be arbitrarily set in terms of its amplitude, period, waveform, and the like. Examples of the method of applying the voltage include a constant voltage DC or AC, a periodic rectangular wave or a sawtooth shape. The control device 20 electrically connected to the power supply 17 controls the magnitude and waveform of the voltage using a wave or the like. When the voltage applied between the electrodes 1 and 2 is DC, one of the electrodes 1 and 2 is formed so as to function as a cathode electrode and the other as an anode electrode. When the voltage applied between the electrodes 1 and 2 is AC, the polarities of the electrodes 1 and 2 are alternately changed periodically, so that both the electrodes 1 and 2 function as a cathode electrode and an anode electrode. Is formed.

Next, a method of reforming water using the above-described apparatus will be described. First, water 15 such as tap water is put into an electrolytic tank 16 and stored. The weak acid and a salt of the weak acid are added to the water 15 and dissolved. Examples of the weak acid include those having an ionization constant (ionization constant) of 10 ^-5 or more, such as citric acid, ascorbic acid, benzoic acid, succinic acid, and salicylic acid. If a weak acid having an ionization constant of less than 10 ^-5 is used, water 15
Cannot be made high, and a predetermined oxidation-reduction reaction cannot be caused at a constant voltage. Although the upper limit of the ionization constant of the weak acid is not particularly limited, it is preferably 10 ^-3 . It is preferable to use citric acid having a high ionization constant among the above weak acids.

The weak acid salts include trisodium citrate, sodium ascorbate, sodium benzoate,
Sodium salts such as disodium succinate and sodium salicylate can be used. It is preferable to use sodium citrate among the salts of the above weak acids. By adding a weak acid and a salt thereof to the water 15 in this manner, it is possible to prepare an acidic buffered aqueous solution having a high conductivity and a small change in pH. The ratio of the added amount of the weak acid and its salt is water 15
Is adjusted to be in the range of 4.5 to 6.5. As shown in FIG. 2 (a), when 0.3 g / liter of sodium citrate is added to tap water (city water of Moriguchi City), the amount of citric acid added is set to about 0.3 g / liter or less. When 0.3 g / liter of sodium citrate is added to groundwater, the amount of citric acid added can be set to about 0.45 g / liter or less. As shown in FIG. 2 (b), when 0.5 g / liter of sodium citrate is added to tap water (city water of Moriguchi City), the amount of citric acid added is about 0.45 g / liter or less. When sodium citrate is added to groundwater at 0.5 g / liter,
The amount of citric acid added can be set to about 0.6 g / liter or less.

As shown in FIG. 2C, when 0.6 g / liter of sodium citrate is added to tap water (city water of Moriguchi City), the amount of citric acid added is about 0.1 to 0.1%.
It can be set to 0.5 g / L, and when sodium citrate is added to groundwater at 0.6 g / L, the amount of citric acid added should be set to about 0.1 to 0.65 g / L. Can be. In addition, as shown in FIG. 2 (d), sodium citrate is supplied to tap water (city water of Moriguchi City).
When 1.0 g / L is added to the water, the amount of citric acid added can be set to about 0.15 g / L or more. When 0.6 g / L of sodium citrate is added to the groundwater, The amount of citric acid added is about 0.1 ~
It can be set to 1.0 g / liter.

The above-mentioned weak acid and its salt may be added to the water 15 to be reformed as a solid, but a predetermined amount is dissolved in a solvent such as water in advance and added to the water 15 to be reformed in a solution state. It may be added. By adding the solution of the weak acid and its salt to the water 15 to be reformed in this way, it is not necessary to weigh the weak acid and its salt during the water 15 reforming operation. The weak acid and its salt can be easily dissolved and dispersed, and the water 15 can be efficiently reformed.

Next, a voltage is applied between the electrodes 1 and 2 in the water 15 to which the weak acid and its salt are added. The magnitude of the voltage is 1
It can be set to 50V. If the voltage is less than 1 V, there occurs a problem that the electrode reaction (reduction reaction) at the cathode electrode does not easily proceed, and if the voltage exceeds 50 V, the electrolytic reaction of water at the anode electrode proceeds, and the oxidation-reduction potential decreases. There is a problem that it is difficult to do so. The voltage application time can be set to 1 to 30 minutes / liter (application time to 1 liter of water to which a weak acid and its salt are added). If the application time is less than 1 minute / liter, the progress of the electrode reaction (oxidation-reduction reaction) is slow, causing a problem that the oxidation-reduction potential does not easily decrease. Since the reaction reaches equilibrium and the oxidation-reduction potential becomes constant, there is a problem that power is wasted and economically disadvantageous.

As described above, when a voltage is applied between the electrodes 1 and 2 in the water 15, an electrochemical reaction of the water 15 and a substance contained (dissolved) in the water 15 on the electrodes 1 and 2, That is, an oxidation-reduction reaction occurs. As a result, the concentration ratio of the oxidation-reduction reaction system composed of the substance contained in the water 15 changes and the oxidation-reduction potential of the oxidation-reduction reaction system decreases.
Since a weak acid and its salt are added to 5, water 15 can be made acidic in which hydrogen ions H ^{+ of the} weak acid are dissociated and a large amount of H ₃ O ⁺ is present. Is 4H ₃ O ⁺ + 6e → 3H ₂ +2
H ₃ O ₂ ^- liable to occur reduction reaction that also the electrodes 1,
In the anode electrode which is the other of the two, M _red → M
An oxidation reaction of _ox + e (other than the reaction that occurs in water electrolysis) occurs.

In other words, by adding a weak acid and a salt thereof to water, the pH can be made substantially constant even if water becomes a buffer solution and a voltage is applied between the electrodes by the buffering action.
The presence of more hydrogen ions in the water than the various ions contained in the water promotes the electrode reaction derived from the water, so that H ₂ is mainly produced in the water and O 2
The formation of ₂ is suppressed, and the reducing substances (H ₃ O ₂ ⁻ ) among the substances contained in the water 15 increase. Therefore, the oxidation-reduction potential of the oxidation-reduction reaction system of the whole water 15 can be greatly reduced, and water with high reducibility can be obtained.

Even if the ionic strength of the water 15 before reforming is low and the conductivity is low, the conductivity is increased by adding a weak acid and the voltage is applied between the electrodes 1 and 2, so that the water 15 15, a constant and predetermined oxidation-reduction reaction can be always generated in a short time at a constant voltage, and water can be reformed efficiently. Further, since the water 15 before reforming is made into a buffered aqueous solution by adding a weak acid and a salt thereof, even if a voltage is applied between the electrodes 1 and 2 due to the buffering action, the pH of the water after reforming remains unchanged. It is possible to obtain acidic and highly reducible water without greatly changing the pH of the water 15.

In the above embodiment, sodium ascorbate can be further added to water 15 to which a weak acid and its salt have been added before reforming (before applying a voltage). Sodium ascorbate is used to reduce free chlorine contained in water 15 (tap water) to form chlorine ions. Therefore, the oxidation-reduction potential of the oxidation-reduction reaction system of water 15 before reforming (voltage is applied) If the reforming is performed by applying a voltage between the electrodes 1 and 2, water having a higher reducing property can be obtained. Since the water 15 to which the weak acid and its salt are added is a buffered aqueous solution,
Even when sodium ascorbate is added, the pH does not change due to its buffering action.

The amount of sodium ascorbate added (water 1
0.008-0.04 g /
Liters are preferred. If the amount of sodium ascorbate added is less than 0.008 g / liter, there is a problem that it is difficult to decompose and remove residual chlorine of 1 mg / liter or more, which is a standard for water quality such as ordinary city water. Occurs. Although there is no particular problem if the amount of sodium ascorbate exceeds 0.04 g / liter,
It is preferable that the added amount is such that 5 mg / liter of chlorine based on HO can be decomposed and removed.

FIG. 3 shows another embodiment of the water reforming apparatus. In this embodiment, electrodes 3 to 5 formed in the same manner as in the above-described embodiment are formed upright on the bottom surface of an electrolytic cell 16 so as to face each other. The electrodes 3, 4, and 5 are electrically connected to a power supply 17 by wirings 21, 22, and 23, respectively, so that a voltage can be applied between the electrodes 3 and 4 and between the electrodes 4 and 5 by the power supply 17. Has become. The voltage applied between the electrodes 3 and 4 and the voltage applied between the electrodes 4 and 5 are set arbitrarily in terms of amplitude, period, waveform, and the like. Rectangular or sawtooth waves are used,
The control device 20 electrically connected to the power supply 17 controls the magnitude and waveform of the voltage.

When the voltage applied between the electrodes 3 and 4 and between the electrodes 4 and 5 is DC, the middle electrode 4 functions as a cathode electrode, and the electrodes 3 and 5 at both ends function as anode electrodes (electrodes). 3, 5 have the same potential). When the voltage applied between the electrodes 3 and 4 and between the electrodes 4 and 5 is an alternating current or a periodic rectangular wave or sawtooth wave, the middle electrode 4 is always a cathode electrode, 5 are both formed so as to periodically and alternately act as a cathode electrode and an anode electrode.

Next, a method of reforming water using this apparatus will be described. First, in the same manner as in the above-described embodiment, water 15 is put into the electrolytic bath 16 and stored therein. Further, a weak acid and its salt, and if necessary, sodium ascorbate are added to the water 15. Next, a voltage is applied between the electrodes 3 and 4 and between the electrodes 4 and 5 in the water 15 to which the weak acid and its salt are added in the same manner as in the above embodiment. When a voltage is applied between the electrodes 3 and 4 and between the electrodes 4 and 5, water 15
Then, an electrochemical reaction of the substance (dissolved) contained in the water 15, that is, an oxidation-reduction reaction occurs. As a result water 1
The concentration ratio of the oxidation-reduction reaction system constituted by the substances contained in 5 changes, and the oxidation-reduction potential of the oxidation-reduction reaction system decreases.

In the present invention, since a weak acid and a salt thereof are added to the water 15, the water 15 can be made acidic such that hydrogen ions H ^{+ of the} weak acid dissociate and a large amount of H ₃ O ⁺ is present,
Therefore, when a DC voltage is used, a reduction reaction of 4H ₃ O ⁺ + 6e → 3H ₂ + 2H ₃ O ₂ ⁻ easily occurs at the electrode 4 of the cathode electrode, and M _{red at} the electrodes 3 and 5 of the anode electrode. → The oxidation reaction of M _ox + e (other than the reaction that occurs in the electrolysis of water) occurs. That is, for the same reason as above, H ₂ is mainly generated, and generation of O ₂ is suppressed, so that the reducing substances among the substances contained in the water 15 increase. Therefore, the oxidation-reduction potential of the oxidation-reduction reaction system of the whole water 15 can be greatly reduced, and water with high reducibility can be obtained.

In addition, the power of alternating current, periodic rectangular wave or sawtooth wave
When pressure is used, 4H is applied to the electrode 4 of the cathode electrode._Three
O⁺+ 6e → 3H_Two+ 2H_ThreeO_Two ^-The reduction reaction
It is easy to stiffen and alternate between anode and cathode
For the electrodes 3 and 5 that change to _red→ M_oxOxidation of + e
The reaction (other than the reaction occurring in the electrolysis of water) and M_ox+ E
→ M_redReduction reaction (other than the reaction that occurs in water electrolysis)
Shown) occurs. In other words, the electrodes 3 and 5 seem to be redox
The original reaction has not occurred and the same reason as above
Mainly in H_TwoIs generated, and O_TwoGeneration is suppressed
And the reducing substances among the substances contained in the water 15 increase.
You. Therefore, the oxidation-reduction potential of the oxidation-reduction reaction system of the whole water 15
Can be greatly reduced, and highly reducing water is obtained.
Is what you can do.

FIG. 4 shows another embodiment of the water reforming apparatus. In this embodiment, electrodes 6 to 10 formed in the same manner as in the above-described embodiment are formed upright on the bottom surface of an electrolytic cell 16 so as to face each other. Electrodes 6, 7,
8, 9, 10 are electrically connected to a power supply 17 by wirings 24, 25, 26, 27, 28, respectively, and a voltage is applied between the electrodes 6, 8, 10 and the electrodes 7, 9 by the power supply 17. You can do it. Electrodes 6, 8, 10
The voltage applied between the electrodes and the electrodes 7 and 9 may have any amplitude, cycle, waveform, etc., and may be set, for example, to a constant voltage DC or AC, or a periodic rectangular wave. The control device 20 electrically connected to the power supply 17 controls the magnitude and waveform of the voltage.

When the voltage applied between the electrodes 6, 8, 10 and the electrodes 7, 9 is DC, the electrodes 6, 8, 1
The electrode is formed so that 0 functions as a cathode electrode and the electrodes 7 and 9 function as anode electrodes (the electrodes 6, 8, and 10 have the same potential, and the electrodes 7 and 9 also have the same potential). When the voltage applied between the electrodes 6, 8, 10 and the electrodes 7, 9 is an alternating current or a periodic rectangular wave or sawtooth wave, the electrodes 6, 8, 10 are always used as cathode electrodes, Both 7 and 9 are formed so as to periodically and alternately act as a cathode electrode and an anode electrode.

Next, a method of reforming water using this apparatus will be described. First, in the same manner as in the above-described embodiment, water 15 is put into the electrolytic bath 16 and stored therein. Further, a weak acid and its salt, and if necessary, sodium ascorbate are added to the water 15. Next, in the same manner as in the above embodiment, the electrodes 6, 8, 10 and the electrodes 7, 9 in the water 15 to which the weak acid and its salt are added.
A voltage is applied during. When a voltage is applied between the electrodes 6, 8 and 10 and the electrodes 7 and 9 in this manner, an electrochemical reaction of the water 15 and a substance contained (dissolved) in the water 15 on the electrodes 3 to 5, That is, an oxidation-reduction reaction occurs. As a result, the concentration ratio of the oxidation-reduction reaction system constituted by the substance contained in the water 15 changes, and the oxidation-reduction potential of the oxidation-reduction reaction system decreases.

In the present invention, a weak acid and a salt thereof are added to water 15.
Since water 15 has been added, water 15⁺Is the solution
Release H_ThreeO⁺Can be acidic, where there are many
Therefore, when a DC voltage is used, the cathode electrode
4H for 6, 8, 10_ThreeO ⁺+ 6e → 3H_Two+ 2H_Three
O_Two ^-Reduction reaction easily occurs, and the anode
In the electrodes 7 and 9 of the electrodes, M_red→ M_ox+ E antioxidant
(Representing reactions other than the reactions that occur in the electrolysis of water). Toes
Mainly for the same reason as above._TwoIs generated, and O
_TwoGeneration is suppressed, and the substances contained in the water 15 are reduced.
Sexual substances increase. Therefore, the redox reaction system of the whole water 15
Can greatly reduce the oxidation-reduction potential of
It can obtain original water.

When an AC voltage is used, the cathode
4H for electrodes 6, 8, and 10 of the electrodes _ThreeO⁺+ 6e → 3H
_Two+ 2H_ThreeO_Two ^-Is easy to occur,
Electrode 7, which alternates between an anode electrode and a cathode electrode,
In 9, M_red→ M_ox+ E oxidation reaction (by electrolysis of water
Other than the reaction that takes place) and M_ox+ E → M_redReturn
The original reaction (except for the reaction that occurs in the electrolysis of water) occurs.
In other words, an apparent redox reaction occurs at the electrodes 3 and 5
And the main reason is that H_TwoBut
Generated and O_TwoIs suppressed and contained in water 15
Of reducing substances increase. Therefore the whole water 15
Can greatly reduce the oxidation-reduction potential of the redox reaction system
It is possible to obtain highly reducing water.
You.

[0032]

The present invention will be described below in detail with reference to examples. (Example 1) The electrodes 3, 4, and 5 were formed from a 60 × 60 mm ² metal plate formed of Pt, and the distance between the electrodes was 5 m.
m was provided on the bottom surface of the electrolytic cell 16 to form the water reforming device shown in FIG.

In the electrolytic cell 16 of the above apparatus, the pH is 7.5, the conductivity is 200 μS, and the oxidation-reduction potential of the oxidation-reduction reaction system is 5
50 mV of Moriguchi City tap water (city water) is charged and stored. 0.3 g / liter of citric acid is added to this water 15 as a weak acid.
0.6 g / liter of trisodium citrate was added and dissolved as a salt of a weak acid. Next, a voltage is applied between the electrodes 3 and 4 and between the electrodes 4 and 5 by the power supply 17 to modify 1 liter of water 15 to which citric acid and trisodium citrate are added. The applied voltage between the electrodes 3 and 4 is a rectangular wave having a frequency of 30 kHz and an amplitude of 10 V as shown in FIG. 5A, and the applied voltage between the electrodes 4 and 5 is shown in FIG. 5B. In addition, the frequency of the phase opposite to the applied voltage between the electrodes 3 and 4 is 30 k
It is a rectangular wave with an amplitude of 10 V at Hz. That is, the voltage is periodically applied between the electrodes 3 and 4 and between the electrodes 4 and 5,
Always acts as a cathode electrode to cause a reduction reaction, and the electrodes 3 and 5 periodically act as a cathode electrode and an anode electrode to alternately generate an oxidation reaction and a reduction reaction. The application time was 5 minutes.

Example 2 The above procedure was repeated except that 0.32 g / liter of ascorbic acid was used as a weak acid instead of citric acid, and 0.32 g / liter of sodium ascorbate was used as a salt of a weak acid instead of trisodium citrate. Water reforming was performed in the same manner as in Example 1.

Example 3 In the same manner as in Example 1 except that groundwater having a pH of 7.1, a conductivity of 250 μS, and an oxidation-reduction potential of an oxidation-reduction reaction system of 600 mV was used instead of tap water. Water reforming was performed. (Example 4) 36 g of citric acid, trisodium citrate 7
2 g was dissolved in 100 cc of water to prepare an acidic aqueous solution (buffer). 0.83 cc of this solution was dropped into tap water (city water) of Moriguchi City stored in the electrolytic cell 16 to prepare water 15 to which citric acid and trisodium citrate were added in the same manner as in Example 1 above. . This water 15 was treated by the same application method as in Example 1 to reform the water.

Example 5 Citric acid as a weak acid was added to the tap water (city water) of Moriguchi city stored in the electrolytic cell 16 at 0.3 g /
Liter, 0.1% trisodium citrate as a weak acid salt.
6 g / liter was added and dissolved. Furthermore, this water 15
0.03 g of sodium ascorbate was added to and dissolved in 1 liter. This water 15 was treated by the same application method as in Example 1 to reform the water.

(Comparative Example) Tap water (city water) from Moriguchi City was treated by the same application method as in Example 1 to reform the water. For Examples 1 to 5, the pH, conductivity, and oxidation-reduction potential of water 15 after the addition of a weak acid and its salt (in Example 5, after addition of sodium ascorbate) were measured (see Table 1). Shown after addition). Further, for the above Examples 1 to 5 and Comparative Example, the pH and the oxidation-reduction potential of water 15 after voltage application were measured (shown as after application in Table 1). Table 1 shows the results.

[0038]

[Table 1]

As can be seen from Table 1, even when the applied voltage and the applied time are the same, Examples 1 to 5 in which the water to which the weak acid and its salt were added were modified were weaker acid and its salt. Oxidation-reduction potential after voltage application can be greatly reduced as compared with the comparative example in which water is reformed without the addition of water. Further, in Examples 1 to 5, the pH of water before and after voltage application can be prevented from being changed by the buffering action of water. However, in Comparative Example, the pH after application is 7.6, which is higher than before application. The pH changed to alkaline. Further, in Example 5, since sodium ascorbate was added to water in addition to citric acid and sodium citrate, free chlorine contained in the water could be decomposed into chloride ions, and the oxidation-reduction potential was reduced before voltage was applied. Therefore, the effect of lowering the oxidation-reduction potential by applying a voltage can be greatly obtained.

[0040]

As described above, according to the first aspect of the present invention, the oxidation-reduction potential of the oxidation-reduction reaction system contained in water is obtained by applying a voltage between a plurality of electrodes arranged in water. When performing water reforming by lowering water, a weak acid and its salt are added to the water, so that the reduction reaction easily occurs in water and the degree of reduction of the oxidation-reduction potential of the oxidation-reduction reaction system contained in water is increased. And water with high reducibility can be obtained. In addition, by adding a weak acid and its salt, the conductivity of water can be increased, and a constant reduction in oxidation-reduction potential at a constant voltage can efficiently reform water in a short time. It is. Further, by using water as an acidic buffer solution, it is possible to lower the oxidation-reduction potential of the oxidation-reduction reaction system without changing the pH of the water even after applying a voltage, and to obtain water exhibiting acidic and high reducibility. Is what you can do.

According to the second aspect of the present invention, since the ionization constant of the weak acid is 10 ^-5 or more, the conductivity of water having low ionic strength and low conductivity can be increased. In this method, a predetermined oxidation-reduction reaction is generated at a constant voltage, and the oxidation-reduction potential of the oxidation-reduction reaction system can be reliably and efficiently reduced. In the invention according to claim 3 of the present invention, since the weak acid and its salt are citric acid and its salt, the conductivity of water can be increased as compared with the case of using another weak acid and its salt, and the efficiency can be improved. It can reduce the oxidation-reduction potential of the oxidation-reduction reaction system well.

In the invention according to claim 4 of the present invention, the pH of the water is adjusted to 4.5 to 6.5 by adding a weak acid and a salt thereof to the water. Water can be obtained. In the invention according to claim 5 of the present invention, since the solution containing the weak acid and its salt is added to water, it is not necessary to weigh the weak acid and its salt during the water reforming operation, and the operability is reduced. The weak acid and the salt thereof can be easily dissolved and dispersed in the water to be reformed, and the water reforming operation can be performed efficiently.

In the invention according to claim 6 of the present invention, since sodium ascorbate is further added to the water, free chlorine contained in the water can be decomposed and removed without changing the pH of the water, Water reforming can be highly promoted. Further, the invention according to claim 7 of the present invention provides an electrolytic cell for storing water to which a weak acid and a salt thereof are added, and a plurality of electrodes arranged in the water stored in the electrolytic cell. Since a power source for applying a voltage between the electrodes is provided, the degree of reduction of the oxidation-reduction potential of the oxidation-reduction reaction system can be increased, and water can be reformed efficiently. Yes, and by using water as an acidic buffer solution, it is possible to lower the oxidation-reduction potential of the oxidation-reduction reaction system without changing the pH of the water even after applying a voltage, and to obtain water that is acidic and highly reducing. Can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing one embodiment of a water reforming apparatus of the present invention.

FIG. 2 (a) is a graph showing the relationship between the concentration of citric acid in water added with 0.3 g / l of sodium citrate and the pH, and FIG. 2 (b) is the concentration of citric acid in water added with 0.5 g / l of sodium citrate And a graph showing the relationship between pH and
(C) is a graph showing the relationship between the citric acid concentration of water added with 0.6 g / liter of sodium citrate and pH, and (d).
Is a graph showing the relationship between the concentration of citric acid in water added with 1.0 g / liter of sodium citrate and pH.

FIG. 3 is a schematic diagram showing an embodiment of another water reforming apparatus according to the embodiment.

FIG. 4 is a schematic diagram showing an embodiment of still another water reforming apparatus according to the embodiment.

5 (a) and 5 (b) are waveform diagrams showing an example of a voltage applied between electrodes of the above.

[Explanation of symbols]

 1 electrode 2 electrode 3 electrode 4 electrode 5 electrode 6 electrode 7 electrode 8 electrode 9 electrode 10 electrode 15 water 16 electrolytic cell 17 power supply

Claims (7)

[Claims] 1. A method in which a voltage is applied between a plurality of electrodes arranged in water to lower the oxidation-reduction potential of an oxidation-reduction reaction system contained in water and reform the water. A method for reforming water, comprising adding a salt thereof. 2. The method according to claim 1, wherein the weak acid has an ionization constant of 10 ⁻⁵ or more. 3. The method according to claim 1, wherein the weak acid and its salt are citric acid and its salt. 4. The water modification according to claim 1, wherein the pH of the water is adjusted to 4.5 to 6.5 by adding a weak acid and a salt thereof to the water. Quality way. 5. The method for reforming water according to claim 1, wherein the solution containing the weak acid and a salt thereof is added to water. 6. The method for reforming water according to claim 1, wherein sodium ascorbate is further added to the water. 7. An electrolytic cell for storing water to which a weak acid and a salt thereof are added, a plurality of electrodes arranged in the water stored in the electrolytic cell, and applying a voltage between the electrodes. A water reforming device, comprising: