JP6528183B2 - Method for producing slightly acidic hypochlorous acid water, bipolar electrolyzer and producing apparatus - Google Patents

Description

  The present invention relates to a technique for producing sterilizing water referred to as slightly acidic hypochlorous acid water (generally referred to as slightly acidic electrolyzed water), and more specifically, a method of producing slightly acidic hypochlorous acid water, a bipolar system The present invention relates to an electrolytic cell and a generator.

  The slightly acidic hypochlorous acid water is designated as a food additive by the Ministry of Health, Labor and Welfare because it is widely used for sterilization, has a high sterilization rate, is nontoxic, non-irritant and inexpensive.

  In addition to food production sites, applications in a wide range of fields such as fisheries, agriculture and medical care are expanding.

  The slightly acidic hypochlorous acid water is defined as one obtained by electrolyzing a hydrogen chloride solution or a mixture of a hydrogen chloride solution and a sodium chloride solution. And as a method of obtaining slightly acidic hypochlorous acid water having high bactericidal activity without containing salt, a method of producing a solution of free hypochlorous acid by electrolyzing a hydrogen chloride solution is put to practical use .

  The effective chlorine concentration range is 10 to 80 mg / L, and the pH range is 5.0 to 6.5, so that the slightly acidic hypochlorous acid water keeps the strong bactericidal activity stable and has high safety. It is said (April 26, 2012 Ministry of Health, Labor and Welfare notification 345).

  However, limiting the range of the effective chlorine concentration and pH to the above range makes it important to carefully control the generation process, considering the fluctuation of components due to the electrolytic conditions of the generation process and the elements of the electrolytic cell.

  The factors of electrolysis that have an important influence on the product include the concentration of the hydrogen chloride solution as the raw material, the supply rate thereof, the structure of the electrolytic cell, the electrolysis voltage and current, and the physical properties of the raw water.

  Furthermore, the mutual relationship between these factors affects the quality of the slightly acidic hypochlorous acid water produced. Therefore, in order to produce slightly acidic hypochlorous acid water of stable quality, the concentration of the hydrogen chloride solution that is the raw material, its supply rate, electrolysis voltage, electrolysis current, dilution water flow rate, structure of the electrolysis tank, physical properties of raw water It is necessary to examine their interactions and to construct the generation process including their control.

  About control of electrolysis In JP, 2011-104519 (patent documents 1), it is a method of producing sterilization water by making it electrolyze by fixed voltage and diluting generated electrolyte solution with dilution water, and an electrolysis current value There is disclosed a technique of controlling to depend on the measured flow rate of dilution water or the concentration of components of sterilizing water. However, in Patent Document 1, the concentration of the hydrogen chloride solution as a raw material, its supply rate, the structure of the electrolytic cell, the electrolysis voltage and current, the physical properties of the raw water, etc. affect the formation of slightly acidic hypochlorous acid water Is not disclosed.

JP, 2011-104519, A

  The present invention has been made in view of the above-described problems of the prior art, and the present invention provides a method for efficiently generating stable acid semi-acidic hypochlorous acid water, bipolar electrolysis It is intended to provide a tank and a generator.

  The inventor investigated in detail the influence of the influence factors such as the concentration of the hydrogen chloride solution which is the raw material, the supply rate thereof, the structure of the electrolytic cell, the electrolysis voltage and current, and the physical properties of the raw water on the product quality. Then, it has been found that by controlling a complex acting factor based on the examination result, it is possible to stably generate a slightly acidic hypochlorous acid water having stable quality, and the present invention has been completed. .

That is, according to the present invention, a slightly acidic hypochlorous acid having an effective chlorine concentration of 10 to 80 mg / L and a pH of 5.0 to 6.5 is electrolyzed by supplying a hydrogen chloride solution with power to an electrode. A method of producing acid water,
A supply opening through which the aqueous solution of hydrogen chloride is supplied; a discharge opening for discharging an electrolyte; and a second opening formed to surround the discharge opening, the supply opening, the discharge opening, Supplying power to the bipolar electrolyzer in which the area increases in the order of the second opening;
Diluting the electrolytic solution discharged from the second opening with water;
Can be provided.

  According to the present invention, it is possible to provide a production method, a bipolar electrolytic cell and a production apparatus for producing slightly acidic hypochlorous acid water having improved generation efficiency, product safety, power efficiency and electrode life.

FIG. 2 shows a detailed embodiment of the electrolyzer. The figure which shows the cross section of the bipolar electrode of the electrode 7. FIG. FIG. 6 illustrates an embodiment of a generation method. The graph which shows the relationship of the density | concentration of the by-product generated by electrolysis voltage and electrolysis.

  Hereinafter, the present invention will be described by way of embodiments, but the present invention is not limited to the embodiments described later. FIG. 1 is a view showing an embodiment of a slightly acidic hypochlorous acid water electrolytic device (hereinafter simply referred to as an electrolytic device).

  The electrolytic device 30 shown in FIG. 1 is configured to include an electrolytic cell configured to include the electrode 7 and an electrolytic device case 16, and the electrolytic device case 16 dilutes the electrolytic solution and the electrolytic cell. Water for cooling (hereinafter referred to as dilution water) is filled. The electrolytic solution containing a high concentration of hypochlorous acid generated by the electrolytic cell is discharged from the opening 11 of the electrolytic cell. The dilution water 14 supplied from the dilution water supply port 19 dilutes the electrolytic solution while cooling the electrolytic cell, and discharges the slightly acidic hypochlorous acid water 12 in the present embodiment from the discharge port 17.

  The electrolytic cell is provided with an insulating frame 15, an upper lid 9, a lower lid 6 and five electrodes 7 in the illustrated embodiment. The frame 15 holds the upper cover 9 and the lower cover 6 in a watertight manner, holds the side end of the electrode 7 and isolates the electrolyte from the dilution water 14. The upper lid 9 and the lower lid 6 hold the upper end and the lower end of the electrode 7 to enable electrolysis under a predetermined potential difference. An electrolytic current is supplied from the power supply (not shown) to the outermost two electrodes 7 through the feeding terminal 18 to form a bipolar electrolytic cell. The electrodes 7 are not limited to flat plates as long as they can be parallel and form a uniform electric field, and may have a shape forming parallel curved surfaces.

  Supply openings 5 for supplying raw materials are respectively formed in the area of the lower lid 6 where the unit electrolytic cell is formed. In addition, a discharge opening 10 for discharging the electrolytic solution is formed in the upper lid 9 for each unit electrolytic cell, and an electrolytic solution containing high concentration of hypochlorous acid is made from the opening 11 to the electrolytic device case 16 The water is discharged to the area filled with the dilution water 14. The electrolytic solution is diluted with dilution water 14 to a predetermined hypochlorous acid concentration and pH, and discharged from the outlet 17 as slightly acidic hypochlorous acid water 12.

  Although the diameters of the supply opening 5 and the discharge opening 10 are not particularly limited, as described in, for example, Japanese Patent No. 4712915, the number of the supply openings 5 may be one or more per unit electrolytic cell. The number and size can be set such that the total opening area is, for example, 0.018 to 0.45% of the effective single-sided area of the electrode. The number of discharge openings 10 may be one or more per unit electrolytic cell, but the total opening area can be, for example, the number and size of 0.036 to 0.9% of the effective single-sided area of the electrode.

  The raw material supply port 4 is formed in the lower part of the frame 15, and the raw material accumulated in the raw material tank (not shown) is supplied to the electrolytic cell using the supply tube 2 and a pump (not shown). In the present embodiment, the raw material uses a hydrogen chloride solution.

  Further, the supply opening 5 receives the supply of the raw material through the common flow path formed in the lower part of the frame 15 so that the supply amount of the raw material to the unit electrolytic cell becomes uniform. The raw materials are supplied from the supply openings 5 to the respective unit electrolytic cells, rise while undergoing electrolysis, and are discharged from the discharge openings 10 as an electrolytic solution.

  The plurality of discharge openings 10 discharge the electrolyte to a common discharge path formed at the top thereof. The common discharge path makes it possible to equalize the outlet pressure of each unit electrolytic cell, and provides a buffer passage which makes the liquid flow rate per unit electrolytic cell uniform. The electrolytic solution is sent to the portion of the electrolytic device case 16 through which the dilution water 14 flows, and is diluted through the common discharge passage through the opening 11 formed in a larger area than the discharge opening 10 formed in the frame 15. The water is discharged from the discharge port 17 as slightly acidic hypochlorous acid water 12. In the bipolar electrolyzer, when a difference in liquid flow rate occurs between unit electrolyzers, the amount of electrical conductivity in the liquid in the unit electrolyzer, which has a particularly low flow rate, decreases, and the electrical conductivity of the entire electrolyzer is reduced. Reduce On the other hand, the electrolytic cell of the present embodiment suppresses the fluctuation given to the quality of the slightly acidic hypochlorous acid water to be produced by uniforming the flow rate of each unit electrolytic cell, and the stable slight acid of stable quality Supply hypochlorous acid water.

  FIG. 2 is a view showing a cross section of the bipolar electrode of the electrode 7. The electrode 7 includes an electrode base 7a, an anode surface 7b, and a cathode surface 7c. The electrode substrate 7a can be made of a material containing titanium or an alloy containing titanium. The anode surface 7b is formed as a film that covers the electrode substrate 7a, and can be formed of a material containing iridium oxide. The cathode surface 7c is formed by covering the electrode substrate 7a with the electrode substrate 7a itself or a substance containing a platinum group metal.

  By employing the bipolar electrode of the above configuration, the electrode 7 can provide appropriate electrolytic characteristics with the anode and the cathode while simplifying the structure of the flat plate electrode, and the electrolytic efficiency is improved. The generation efficiency of the acidic hypochlorous acid water can be improved. Furthermore, since the electrode 7 can be thinned, the volume of the electrolytic cell can also be reduced.

  FIG. 3 is a schematic view showing a production apparatus for producing slightly acidic hypochlorous acid water 12 using the electrolytic device 30 of FIG. In FIG. 3, the internal structure of the electrolytic device case 16 is as described with reference to FIGS. 1 and 2, and thus the detailed description is omitted. The hydrogen chloride solution, which is a raw material, is accumulated in the raw material tank 1, and the raw material is supplied to the electrolytic cell inside the electrolytic device housing 16 using the supply tube 2 and the pump 3. The power supply 13 is connected to the feed terminal 18 and supplies an electrolytic current to the electrolytic cell. The value of the electrolytic current is measured by an ammeter 20.

  The current value measured by the ammeter 20 is given to the controller 21. The control device 21 can control the operation of the pump 3 in the case of continuously performing electrolysis in accordance with the fluctuation of the current value. For example, the range of the current value is set in advance in the control device 21, and when the measured current value is less than the set value, the pump 3 is operated to start the supply of the raw material. When the measured current value exceeds the set value, the pump 3 is stopped to stop the supply of the raw material. This makes it possible to keep the rate of electrolysis constant even when performing electrolysis continuously.

  In the following, the voltage per unit electrolytic cell, the distance between the adjacent electrode surfaces (hereinafter referred to as electrode spacing) for efficiently generating slightly acidic hypochlorous acid water in the generating apparatus of FIG. 3 Current value per unit area of electrode (hereinafter referred to as current density), millimole number of pure hydrogen chloride supplied per unit volume of unit electrolytic cell per unit time (hereinafter referred to as hydrogen chloride supply amount), And electric quantity per millimole of hydrogen chloride (hereinafter referred to as current value per unit rate of hydrogen chloride supply).

  The voltage applied per unit electrolytic cell can be preferably 0.5 V or more and 6.0 V or less, more preferably 1.5 V or more and 4.0 V or less. If the voltage is less than 0.5 V, the generation efficiency of chlorine decreases, and if the voltage exceeds 6.0 V, the generation amount of chlorine increases, but a by-product is generated, and as a slightly acidic hypochlorous acid water The quality gets worse. And, by setting the voltage applied per unit electrolytic cell to 1.5 V or more and 4.0 V or less, stable, efficient and high quality can be achieved even when an automatic voltage setting error occurs in control. Slightly acidic hypochlorous acid water can be produced.

  The electrode spacing can be preferably 0.5 mm or more and 10 mm or less, and more preferably 1 mm or more and 8 mm or less. If the electrode distance is less than 0.5 mm, bubbles generated during electrolysis are difficult to separate, and the current is not stable. In addition, when the electrode distance exceeds 10 mm, the power efficiency is deteriorated due to the loss of electric power and the deterioration of the renewal of the electrolytic solution in the electrolytic cell. Therefore, by setting the electrode distance to 1 mm or more and 8 mm or less, the slightly acidic hypochlorous acid water is stably and efficiently generated while preventing the influence of the variation in dimensional accuracy at the time of manufacturing the generating device. be able to.

  Also, the electric field strength can be defined from the voltage applied per unit electrolytic cell and the electrode interval. The electric field strength is a value obtained by dividing the voltage by the electrode interval, and from the upper limit value and the lower limit value of the voltage applied per unit electrolytic cell and the electrode interval as described above, 0.1875 V / mm or more, 4.0 V / mm Thus, it is possible to efficiently produce slightly acidic hypochlorous acid water.

The current density is preferably 0.05 mA / mm ² or more, 1.0 mA / mm ² or less, more preferably 0.2 mA / mm ² or more, it may be 0.6 mA / mm ² or less. When the current density is less than 0.05 mA / mm ² , the electrode area is increased, which leads to a decrease in the amount of electrolysis per unit area and an increase in the size of the generator. In addition, when the current density exceeds 1.0 mA / mm ² , the consumption of the electrode becomes fast, and as a result, the life of the generator is shortened. Accordingly, current density 0.2 mA / mm ² or more, by a 0.6 mA / mm ² or less, can limit the generator size is long-term stable operable, providing an economically advantageous generator can do.

Amount of hydrogen chloride supplied, preferably 0.0006mMol / hmm ³ or more, 0.013 mmol / hmm ³ or less, more preferably 0.0013 mmol / hmm ³ or more, it is possible to 0.0063mMol / hmm ³ below. Is less than ³ weight hydrogen chloride supply 0.0006mMol / hmm, leads to a decrease in power efficiency due to power loss, the amount of hydrogen chloride supplied exceeds 0.013 mmol / hmm ^3, leads to a decrease in conversion of chlorine. Therefore, by setting the hydrogen chloride supply amount to 0.0006 mMol / hmm ³ or more and 0.013 mMol / hmm ³ or less, an appropriate chlorine generation efficiency can be maintained. The hydrogen chloride supply amount M is a value obtained from the following formula (1) as the hydrogen chloride substance mass n, the electrolysis time t, the electrode area S, and the electrode distance D.

The ratio of the current I to the supply amount of the raw material (the product of the electrode area S, the electrode spacing D, and the hydrogen chloride supply amount M), taking into consideration that the various conditions described so far affect each other, specifically, The current value I _HCl per hydrogen chloride unit feed rate given by the following formula (2) is 1.90 mAh / mMol or more and 460 mAh / mMol or less, more preferably 9.20 mAh / mMol or more and 230 mAh / mMol or less be able to. If the current value per unit rate of hydrogen chloride supply is within the above range, it is possible to maintain a constant electrolytic state and to control the characteristics of the product to a constant.

Up to this point, the present invention has been described by way of embodiments, but the present invention will be described below by more specific test examples and examples.
(Test Example 1)

Using the generator described in FIG. 1, a solution containing 0.15% hydrogen chloride was electrolyzed in a unit cell arranged at an electrode spacing of 3 mm. The electrode used was a titanium plate having an area of 2500 mm ² (50 mm × 50 mm) in which the anode was coated with iridium oxide and the cathode was coated with platinum. At various voltages, using a batch electrolytic device, electrolysis was started from an arbitrary initial current value, and the electrolysis ended when the current value decreased to 95% of the initial value. The amount of chlorine was determined by combining the amount collected in the air and the amount remaining in the electrolyte, determined by iodine titration, and converted to the amount generated per unit time. The ratio of the theoretical generation amount to the theoretical value is a ratio of the actual generation amount to the theoretical generation amount calculated from the electric amount and the Faraday constant, and is calculated by the following equation (3).

  Here, C in the formula (3) represents the chlorine generation amount (mg), F represents the Faraday constant (96500 C / Mol), I represents the current value (A), t represents the generation time (seconds), and 35. 5 is the atomic weight of chlorine. The results of the electrolysis are shown in Table 1 below.

  Next, since it is known that the type of by-products by side reaction increases when electrolysis is performed at a high voltage, the generated by-products were examined according to the value of the electrolysis voltage. The hydrogen chloride solution was electrolyzed at each voltage for 5 minutes, and byproducts in the electrolyte were measured by ion chromatography equipped with a conductivity detector. The results of the generated by-products are shown in Table 2 below and FIG.

From Table 1 and Table 2 and FIG. 4, chlorine was efficiently generated at an electrolysis voltage of 1.5 V or more, and no by-product was produced at an electrolysis voltage of 4.0 V or less. It was confirmed that it was done.
(Test Example 2)

  A 0.15% hydrogen chloride solution was electrolyzed under the same other conditions except that the electrode spacing of the electrolytic cell in the generator used in Test Example 1 was changed. The electrolysis voltage was a voltage required to flow a current of 2.5 A, and the ratio to the theoretical value generation amount was measured. The results are shown in Table 3 below.

From Table 3, it can be seen that when the electrode distance is increased, the electrical resistance is increased, and power loss occurs. In addition, the flow of the liquid in the electrolytic cell becomes complicated, and the renewal of the electrolytic solution in the cell becomes worse, whereby the power efficiency is lowered. On the other hand, in the case where the electrode distance was 0.5 mm, the fluctuation of the current value due to the retention of the generated bubbles was observed. Therefore, it was confirmed that good electrolysis can be achieved by setting the electrode interval to 1 mm or more and 8 mm or less.
(Test Example 3)

A solution containing 1% hydrogen chloride was electrolyzed at various current densities using the generator described in FIG. As an electrode, a titanium surface coated with a coating material containing iridium oxide as a main component with a thickness of 0.2 μm was used as an anode surface, and a solid titanium surface was used as a cathode surface. The area of the electrode was 2500 mm ² (50 mm × 50 mm). In order to maintain the set current density, in the generation method of FIG. 3, the raw material is supplied when the current value is less than the set value, and the supply is stopped when the set value is exceeded. In addition, the liquid temperature is maintained at 45 ° C to accelerate the consumption of the electrode, and the current value can not be maintained under the initially set voltage condition (2.5 V), and the time until the supply of the raw material becomes continuous lasts It was time. The results of the electrolysis are shown in Table 4 below.

From the results of Table 4, it can be confirmed that the endurance time for practical use can be obtained if the current density is 0.6 mA / mm ² or less. On the other hand, when the current density is less than 0.2 mA / mm ² , the amount of electrolysis per electrode area decreases, and the lifetime effect combining the current density and the endurance time decreases, and it can be confirmed that it is economically disadvantageous. The
(Test Example 4)

Using the production apparatus of FIG. 1, the voltage per unit electrolytic cell was electrolyzed at 2.5 V while continuously supplying 0.15% hydrogen chloride solution at various supply amounts, and the chlorine conversion rate was measured. As the electrode, the anode surface was a titanium surface coated with iridium oxide, and the cathode surface was a solid titanium surface. The electrode area was 7500 mm ² (50 mm × 150 mm), and the electrode distance was 3 mm. The chlorine conversion is the ratio of chlorine contained in the generated hypochlorous acid to the total chlorine ions supplied. The amount of chlorine contained in hypochlorous acid was determined by iodine titration. The measured results are shown in Table 5 below.

Table 5 pairs theoretical generation quantity ratio and chlorine conversion rate, the amount of hydrogen chloride supplied, 0.0006mMol / hmm ³ or more, 0.013 mmol / hmm ³ following range is confirmed to be appropriate. Moreover, when the voltage per unit electrolytic cell was measured as 2V and 3V, it has confirmed that the range of the suitable hydrogen chloride supply was the same.
Test Example 5

A 0.25% hydrogen chloride solution was electrolyzed at an applied voltage of 2.5 V per unit electrolytic cell using the production apparatus of FIG. 1, and the chlorine conversion rate and the theoretical value generation ratio were measured. As the electrode, the anode surface was a titanium surface coated with iridium oxide, and the cathode surface was a solid titanium surface. The electrode area was 2500 mm ² (50 mm × 50 mm). The current value per unit hydrogen chloride supply rate given by the equation (2) is a range of each factor shown in Test Examples 2 to 4, current density 0.2 to 0.6 mA / mm ² , electrode spacing 1 ～8Mm, the lower limit and the upper limit of the hydrogen chloride supply amount 0.0013~0.013mMol / hmm ^3, the minimum boundary 1.92mAh / mMol, maximum boundary obtained as 462mAh / mMol. The results of the chlorine conversion and the theoretical value generation ratio measured under the conditions of both boundaries are shown in Table 6 below.

  From the results in Table 6, it was confirmed that electrolysis was carried out with a practical chlorine conversion rate and a theoretical value generation ratio in the range of 1.92 to 462 mAh / mMol of the current value per hydrogen chloride unit feed rate. .

  A production apparatus having the same configuration as the production apparatus shown in FIG. 1 was manufactured for a company on a scale that produces 15000 liters per hour of slightly acidic hypochlorous acid water having an effective chlorine concentration of 20 ppm. The electrolytic cell was a bipolar electrolytic cell consisting of 18 unit electrolytic cells. The amount of chlorine required to produce the above-mentioned amount of slightly acidic hypochlorous acid water is about 300 g (8.45 Mol) per hour, so the amount of electricity required is 815,000 coulombs. Assuming that the generation rate is 50%, the required total current value is 453 A, and the current value per unit electrolytic cell is 25 A.

Since the current value per electrode is 25 A, assuming that the current density is 0.4 mA / mm ² which is an intermediate value of the results in Table 4, the electrode area is 62900 mm ² , so an electrode of 420 mm × 150 mm was used. . The electrode spacing was 4 mm. The anode surface was coated with a mixture containing iridium oxide as a main component on a titanium plate, and the cathode surface was coated with platinum on a titanium plate.

Amount of hydrogen chloride supplied, and arranging by substituting the above current density and electrode spacing in equation (2), since it is calculated as 0.00022~0.0053mMol / hmm ^3, the intermediate value 0.002 mmol / hmm ³ And From this value, 3.3 liters per hour of a 10% hydrogen chloride solution were fed.

  When a voltage of 36 V is applied to the electrolytic cell under the above conditions, the current value changes from 35 to 38 A, and slightly acidic hypochlorous acid water having a pH of 6.0 to 6.3 and an effective chlorine concentration of 15 to 20 ppm, It produced stably at 15000 liters per hour. In this generator, electrolysis is performed at an applied voltage of 36 V, and supply of the hydrogen chloride solution is started when it is less than 24.5 A, and constant current operation is performed to stop the supply of the hydrogen chloride solution when it exceeds 25.5 A. The As a result, a slightly acidic hypochlorous acid water having an effective chlorine concentration of 18 ± 2 ppm and a pH of 6.1 ± 0.2 could be stably produced at 15,000 liters per hour.

  A production unit with the same configuration as the production unit shown in FIG. 1 was manufactured on a scale producing 50 liters of slightly acidic hypochlorous acid water with an effective chlorine concentration of 30 ppm per hour for home use or small-scale users. . The amount of chlorine required to produce the above-mentioned amount of slightly acidic hypochlorous acid water is 1.5 g per hour, and if the production efficiency is 50%, the current needs 1.1 A in the entire electrolytic cell It is.

Here, in order to miniaturize the generator, an electrode of 20 mm × 50 mm was used so that the electrode distance was 1 mm and the current density was 0.6 mA / mm ² . The anode surface was coated with a mixture containing iridium oxide as a main component on a titanium plate, and the cathode surface was coated with platinum on a titanium plate. Moreover, the size of the whole electrolytic cell was miniaturized with 30 mm x 65 mm x 15 mm by setting it as a bipolar electrolytic cell which consists of two unit electrolytic cells.

Amount of hydrogen chloride supplied, and arranging by substituting the above current density and electrode spacing in equation (2), since it is calculated as 0.0013~0.32mMol / hmm ^3, the intermediate value 0.15 mmol / hmm ³ And From this value, 0.3 liter of 5% hydrogen chloride solution was supplied per hour.

  Under the above conditions, a voltage of 2.5 V was applied per unit electrolytic cell and electrolyzed, and 50 liters per hour of slightly acidic hypochlorous acid water having a pH of 5.4 to 5.6 and an effective chlorine concentration of 30 ppm. It was able to generate stably.

  From the embodiments and examples described above, according to the present invention, slightly acidic hypochlorous acid water can be produced stably and efficiently. Moreover, the application can be widely applied from a small-scale generator for household use to a large-scale generator for business.

1: raw material tank 2: supply tube 3: pump 4: raw material supply port 5: supply opening 6: lower lid 7: electrode 7 a: electrode substrate 7 b: anode surface 7 c: cathode surface 9: upper lid 10: discharge opening 11: opening 12: slightly acidic hypochlorous acid water 13: power supply 14: dilution water 15: frame 16: electrolytic device case 17: outlet 18: power supply terminal 19: dilution water supply port 20: ammeter 21: control device 30: electrolysis apparatus

Claims (6)

A method of producing a slightly acidic hypochlorous acid water having an effective chlorine concentration of 10 to 80 mg / L and a pH of 5.0 to 6.5 by electrolyzing a hydrogen chloride solution by supplying power to an electrode ,
A substrate containing titanium or an alloy containing titanium, and an electrode containing a film of iridium oxide or platinum group metal covering at least one surface of the substrate, and a supply opening to which the aqueous solution of hydrogen chloride is supplied A discharge opening for discharging the electrolyte, and a second opening formed to surround the discharge opening, wherein a total opening area of the supply opening, a total opening area of the discharge opening, the second opening Supplying power to the bipolar electrolyzer in which the area of the
Diluting the electrolytic solution discharged from the second opening with water;
Method, including. The supply opening is formed to be 0.018 to 0.45% of the one side area of the electrode, and the discharge opening is formed to be 0.036 to 0.9% of the one side area of the electrode. To be
The method of claim 1. Furthermore the power to the ^electrode, comprising the step of controlling so that the current density of ^{0.2mA / mm 2 ~0.6mA / mm 2} ,
A method according to claim 1 or claim 2. A bipolar system that produces a slightly acidic hypochlorous acid water having an effective chlorine concentration of 10 to 80 mg / L and a pH of 5.0 to 6.5 by electrolyzing a hydrogen chloride solution by supplying power to an electrode An electrolytic cell,
A substrate containing titanium or an alloy containing titanium, and an electrode containing a film of iridium oxide or platinum group metal covering at least one surface of the substrate, and a supply opening to which the aqueous solution of hydrogen chloride is supplied A discharge opening for discharging the electrolyte, and a second opening formed to surround the discharge opening, wherein a total opening area of the supply opening, a total opening area of the discharge opening, the second opening The area of the electrode increases in order, and the electrolytic solution discharged from the second opening is diluted with water . The supply opening is formed to be 0.018 to 0.45% of the one side area of the electrode, and the discharge opening is formed to be 0.036 to 0.9% of the one side area of the electrode. To be
The bipolar electrolytic cell according to claim 4. A bipolar electrolyzer according to any one of claims 4 to 5,
A power supply for supplying an electrolytic current to the bipolar electrolyzer;
A pump for supplying a raw material to the bipolar electrolyzer;
An ammeter for measuring the value of the electrolytic current;
The value of the electrolytic current controls the operation of the pump such that the current density of 0.2mA ^/ mm ² ~0.6mA / mm 2 controlling the concentration of hydrogen chloride between the electrodes of the multi-pole type electrolytic cell And a controller that operates at a constant current so as to generate slightly acidic hypochlorous acid water.