KR20120071983A - System for generating disinfectants - Google Patents

Abstract

PURPOSE: A system for generating a sterilizing agent is provided to easily eliminate microorganisms by electrolyzing tap water and generating the sterilizing agent based on low voltages. CONSTITUTION: A system for generating a sterilizing agent includes an electrolyzing cell(340) and an AC-DC current converting part(330). The electrolyzing cell is composed of an anodic current electric supplier, an anode catalytic bed, a cathodic current electric supplier, a cathode catalytic bed, and a membrane maintaining a distance between the anode catalytic bed and the cathode catalytic bed. The anode catalytic bed is based on iridium oxide, and the cathode catalytic bed is based on platinum. The anode catalytic bed is formed at the anodic current electric supplier, and the cathode catalytic bed is formed at the cathode current electric supplier. A distance between the anode catalytic layer and the cathode catalytic layer is between 10 and 200um. The thickness of the membrane for maintaining the distance is between 10 and 200um.

Description

Fungicide Generation System {SYSTEM FOR GENERATING DISINFECTANTS}

In the present invention, a disinfectant generating system consisting of an AC-DC current converter and an electrolysis cell, wherein the electrolysis cell includes a positive electrode current feeder, a positive electrode catalyst layer, a negative electrode current feeder, a negative electrode catalyst layer, and a distance between the positive electrode catalyst layer and the negative electrode catalyst layer. The anode catalyst layer is made of iridium oxide, the cathode catalyst layer is made of platinum, the anode catalyst layer is formed on the anode current feeder, and the cathode catalyst layer is formed on the distance maintaining film. It characterized in that it relates to a fungicide generating system.

Hypochlorite with excellent sterilizing power is widely known to be obtained by electrolysis of brine or tap water, but there are still many problems to be solved.

1 illustrates the principle of producing hypochlorous acid by electrolyzing tap water in the electrolysis cell 100. Electrolysis unit cell 100 is composed of a positive electrode 110 and a negative electrode 120, when applying a direct current (I) to the chlorine ions existing between the positive electrode 110 and the negative electrode 120, Reaction takes place.

Anode 110:

_{2H 2 O → O 2 ↑ +} 2H + + 2e - ( scheme 1)

_{^{2Cl - → Cl 2 + 2e -}} ( scheme 2)

Cathode 120:

^{_{2H 2 O + 2e - → H}} 2 ↑ + 2OH - ( scheme 3)

Reaction in solution:

_{Cl 2 + H 2 O ⇔ HClO} + H + + Cl - ( Reaction Scheme 4)

Oxygen gas (O ₂ ) and chlorine gas (Cl ₂ ) are generated as water or chlorine ions lose electrons on the surface of the anode (110), and the production rate of oxygen gas (O ₂ ) and chlorine gas (Cl ₂ ) is positive. It is determined by the electrode catalyst applied to 110. In general, it is known that tap water electrolysis has an electrical efficiency of about 1% of platinum and 10% of iridium oxide.

Water molecules receive electrons on the surface of the cathode 120 to generate hydrogen gas (H ₂ ). Chlorine gas generated at the anode 110 continues to react with water in the solution to produce hypochlorous acid (HClO).

On the other hand, the cathode 120 surface in the OH produced by the reaction formula ^3, and the pH is raised by, Ca ^{2 +} or Mg ^{2 +} and reaction (Scheme 5 and Scheme 6), magnesium hydroxide and calcium hydroxide in the water, etc. Is generated. These products precipitate as a solid on the surface of the electrode, forming a calcite membrane that hinders the flow of current.

OH-+ Mg ² + ^- > Mg (OH) ₂ (Scheme 5)

2OH-+ Ca ² + ^- > Ca (OH) ₂ (Scheme 6)

The electrolysis cell 100 as described above has a problem in that calcium and magnesium, which are impurities present in water, accumulate in the scale form on the surface of the cathode 120, and have to be periodically removed. This increases the attendant equipment and maintenance costs.

In general, electrolysis of tap water (salts of less than about 100 ppm) has low electrolysis efficiency, which leads to a large amount of electricity, which leads to an increase in operating costs and related accessories for operating electrolysis cells and electrolysis cells (e.g., For example, there is a problem that the size of the DC power supply) increases.

2 is a structural diagram of an electrolysis cell system 200 for generating a conventional fungicide.

The electrolysis cell system 200 includes an external power source 210, an electrolysis cell 220, and an anode 222 and a cathode 224 in the electrolysis cell. The positive terminal 212 and the positive electrode 222 of the external power source 210 are electrically connected, and the negative terminal 214 and the negative electrode 224 of the external power source 210 are electrically connected. The function of the positive electrode 222 and the negative electrode 224 is as described above in Figure 1, the external power supply 210 serves to supply a direct current power to the electrolysis cell by converting an alternating current into a direct current.

The above mentioned problems are summarized as follows.

First, the electrical resistance of tap water existing between the anode and the cathode is large.

Second, the electrolysis efficiency is low.

Third, scale accumulates in the cathode in the electrolysis cell.

The effects of the above-mentioned problems are as follows.

First, the device of the electrolysis cell becomes large, the power consumption increases, and the installation cost and operation cost rise.

Second, the size of the DC power supply in addition to the electrolysis cell has a problem.

Third, the descaling cycle accumulated in the cathode becomes frequent, and thus there is a problem of reducing the lifetime of the electrode and increasing the operating cost.

The present invention relates to a disinfectant generating system through tap water electrolysis, and to provide a means for generating effective chlorine with high efficiency and low voltage. In addition, the present invention is to provide a method for automatically removing the scale accumulated in the cathode in the electrolysis cell, reducing the management and operating costs.

However, the problem to be solved by the present invention is not limited to the above-mentioned problem, but also include other problems not mentioned, as well as all will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, an aspect of the present invention, in the disinfectant generating system consisting of an AC-DC current conversion unit, an electrolysis cell, the electrolysis cell is a cathode current feeder, anode catalyst layer, cathode current feed It is composed of a whole, a cathode catalyst layer, and a membrane for maintaining the distance between the anode catalyst layer and the cathode catalyst layer, the anode catalyst layer is composed of iridium oxide, the cathode catalyst layer is composed of platinum, the anode catalyst layer is formed on the anode current feed And the cathode catalyst layer is formed on the distance maintaining membrane.

In the tap water electrolysis cell, the distance between the anode catalyst and the membrane is physical zero and the distance between the cathode catalyst and the membrane is maintained by chemical bonding, thereby providing a method of greatly improving the efficiency and voltage of the electrode.

In addition, the present invention is a method for maintaining the electrode gap between the cathode catalyst and the cathode catalyst, it is another feature that is configured by inserting a membrane capable of ion conduction without electrical conductivity.

In another aspect, the present invention is characterized in that the cathode catalyst and the anode catalyst is composed of a catalyst so that the reverse current can be supplied.

According to the present invention, it is possible to easily electrolyze tap water to generate a high-efficiency, low-voltage disinfectant, can be easily used to remove microorganisms, it is expected that a better public health welfare.

1 is a principle diagram for producing hypochlorous acid by electrolysis of tap water.
2 is a structural diagram of an electrolysis cell system for generating a conventional fungicide.
3 is a view of a fungicide generating system according to an embodiment of the present invention.
4 is a diagram illustrating a waveform of a current generated by an AC-DC current converter according to an exemplary embodiment of the present invention.
5 is a view showing an electrolysis cell for electrolyzing tap water according to an embodiment of the present invention.
6 is a diagram showing the performance-voltage of an electrolysis cell according to an embodiment of the present invention and a comparative example.
7 is a diagram illustrating performance-current efficiency of an electrolysis cell according to an embodiment of the present invention and a comparative example.
8 is a view showing the voltage of the electrolysis cell according to an embodiment of the present invention and a comparative example.

DETAILED DESCRIPTION Hereinafter, embodiments and embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention.

Hereinafter, referring to FIGS. 1 to 8, the fungicide generating system will be described in detail.

One aspect of the present invention, in the disinfectant generation system consisting of an AC-DC current converter 330, an electrolysis cell 340, the electrolysis cell 500 is a positive electrode current feeder 510, a positive electrode catalyst layer ( 520, a cathode current feeder 530, a cathode catalyst layer 540, and a membrane 550 for maintaining the distance between the anode catalyst layer 520 and the cathode catalyst layer 540, wherein the anode catalyst layer 520 is iridium oxide. The cathode catalyst layer 540 is formed of platinum, the anode catalyst layer 520 is formed on the anode current feeder 510, and the cathode catalyst layer 540 is the distance maintaining membrane 550. Characterized in that formed, provides a fungicide generating system.

3 is a view showing the tap water electrolytic sterilizer generating system 300 of the present invention, the sterilant generating system is composed of an AC-DC current converter 330, the electrolysis cell 340 as shown in FIG.

The AC-DC current converter 330 converts an alternating current into direct current and converts and supplies an appropriate current and voltage to the electrolysis cell 340. The voltage supplied from the current converter 330 to the electrolysis cell 340 is preferably 1.3-5V. At 1.3 V or less, chlorine and ozone, which are disinfectants, are difficult to generate, and at 5 V or higher, heat generation may occur due to unnecessary overvoltage, which may cause problems in durability of the components of the electrolysis cell 340. For reference, the chlorine generation potential is 1.32 V, and the ozone generation potential is 2.0 V.

In an exemplary embodiment, the current supplied from the AC-DC current converter 330 to the electrolysis cell 340 is provided by crossing the current flowing from the cathode to the anode and the current flowing from the anode to the cathode, and at the cathode. The ratio Ac / Aa of the current value Aa flowing to the anode and the current value Ac flowing from the anode to the cathode is 0.001 to 1, and the retention time Ta of the current flowing from the cathode to the anode and the current flowing from the anode to the cathode The ratio Tc / Ta of the holding time Tc is 0.001 to 1, and the holding time Ta of the current flowing from the negative electrode to the positive electrode is 0.1 hour to 24 hours.

4 is a view showing the waveform of the current generated in the AC-DC current converter 330 of the present invention. The current supplied from the AC-DC current converter 330 of the present invention to the electrolysis cell 340 is equal to the current in the positive direction (when flowing from the cathode to the anode) and in the negative direction (when flowing from the cathode to the cathode). It is preferable to supply current alternately. The scale formed on the negative electrode forms an atmosphere having a low pH by changing the polarity of the negative electrode, thereby effectively removing the scale formed on the negative electrode.

The ratio Ac / Aa between the current value Aa in the positive direction and the current value Ac in the negative direction is between 0 and 1, and the positive direction current holding time ta and the negative direction current holding time tc The ratio tc / ta is preferably 0 to 1. At this time, the positive direction current holding time ta is preferably between 0.1 hour and 1 day. If the positive direction current holding time ta is 0.1 hour or less, frequent polarity switching results in an excessive load on the positive electrode, the negative electrode, and the AC-DC current converter 330, thereby shortening the lifespan, and the positive direction current holding time ( If ta) is greater than 1 day, it becomes difficult to remove the attached scale even if the polarity is switched.

In an exemplary embodiment, the distance maintaining film 550 may be electrically conductive and ion-conductive, but is not limited thereto.

5 is an electrolysis cell 500 for electrolyzing tap water of the present invention, the anode current feeder 510, the anode catalyst layer 520, the cathode current feeder 530, the cathode catalyst layer 540, and the anode catalyst layer ( 520 and the cathode catalyst layer 540 for maintaining the distance. The tap water electrolysis cell of the present invention is a method of maintaining the electrode gap between the anode catalyst layer 520 and the cathode catalyst layer 540, but has no electrical conductivity, but constitutes a membrane 550 capable of ion conduction.

In the present invention, the anode catalyst layer 520 and the cathode catalyst layer 540 are preferably a catalyst made of a platinum group or a platinum group alloy, and specifically, a platinum group metal (platinum, ruthenium, rhodium, palladium, osmium, iridium), gold, Alloys with one or more metals selected from the group consisting of silver, chromium, iron, titanium, manganese, cobelt, nickel, molybdenum, tungsten, aluminum, silicon, zinc and tin are preferred. The electrode catalyst layers 520 and 540 may include a polymer in addition to the platinum group catalyst. Applicable polymers are ion exchange resins. The ion exchange resin contained in the catalyst layer may be the same as or different from the ion exchange resin constituting the ion exchange membrane 550.

In addition, the thickness of the electrode catalyst layers 520 and 540 affects the characteristics of the electrolysis reaction associated with water diffusion in the catalyst layer. When the thickness of the electrode catalyst layers 520 and 540 is 20 µm or more, the loss of catalyst utilization due to the excessive use of the catalyst is a problem, and when the thickness of the catalyst layer is 1 µm or less, the amount of catalyst present per unit area may be low and thus the reaction activity may be low. Is the thickness of 1? 20 μm is preferred. In order to control the thickness of the catalyst layer, the coating may be repeated until the predetermined thickness is reached.

In an exemplary embodiment, the distance between the anode catalyst layer 520 and the cathode catalyst layer 540 may be 10 to 200 μm, but is not limited thereto.

The membrane 550 maintains the distance between the anode catalyst layer and the cathode catalyst layer and prevents electrical short between the anode catalyst layer 520 and the cathode catalyst layer 540. Therefore, although the membrane is a polymer of dense or porous structure and does not have electrical conductivity, it must be possible to transfer the electrolyte. In the case of the polymer having a dense structure, it is desirable to have an ion exchange function to allow the movement of the electrolyte. As the corresponding membrane, a polymer structure having acidic groups such that porous or ions can be selectively moved to a hydrocarbon-based or fluorocarbon-based polymer is preferable. The most preferable structure is a membrane having a strong acid group in the form of ˜SO ₃ in a fluorocarbon polymer having excellent heat resistance and oxidation resistance.

In an exemplary embodiment, the thickness of the distance maintaining film 550 may be 10 to 200 μm, but is not limited thereto.

The thickness of the film 550 is preferably 10 to 200 mu m. 10 μm or less may cause an electrical short between the anode catalyst layer 520 and the cathode catalyst layer 540 during the process of forming the anode catalyst layer 520 and the cathode catalyst layer 540 as both of the membranes 550. In addition, when the thickness of the film 550 is 200 µm or more, there is a problem in that the voltage increases rapidly due to a large transfer resistance.

Generally, there are two methods for forming the anode catalyst layer 520 and the cathode catalyst layer 540 on the membrane 550, but the present invention is not limited thereto.

First, there is a method of forming the electrode catalyst layers 520 and 540 on the current feeders 510 and 530. That is, the current feeders 510 and 530 serve to transfer current applied from an external power source to the electrode catalyst layers 520 and 540, and are composed of a single layer of a porous or plate-like base material or a composite layer of these stacked. It is composed. The precursor of the catalyst is doped into the electrode catalyst layers 520 and 540 and then pyrolyzed, or the catalyst is prepared in advance and hot pressed into the current feeders 510 and 530 to form the electrode catalyst layer.

Second, there is a method of forming the electrode catalyst layers 520 and 540 in the membrane 550. That is, the method of forming the electrode catalyst layers 520 and 540 in the membrane 550 may be a method of depositing the electrode catalyst layers 520 and 540 directly in the membrane 550 and the membrane 550 by manufacturing the electrode catalyst layers 520 and 540. ) And a crimp with a space between them.

In the tap water electrolysis of the present invention, the most preferred electrolysis cell is composed of iridium oxide as the anode catalyst layer 520 and platinum as the cathode catalyst layer 540. In the electrolysis cell 500, the formation position of the iridium oxide of the anode catalyst layer 520 is the current feeder 510, and the formation position of the platinum of the cathode catalyst layer 540 is the membrane 550. That is, the distance between the anode catalyst layer 520 and the membrane 550 is physically zero, and the cathode catalyst layer 540 and the membrane 550 are preferably formed by chemical bonding.

It is not preferable to form the anode catalyst layer 520 iridium oxide directly on the film. The most ideal of the anode catalyst layer 520 is iridium oxide, and the method of manufacturing iridium oxide is difficult to manufacture by a general method, and the ideal method is sintering. Therefore, forming the iridium oxide catalyst on the polymer film 550 has a problem of high cost and complexity of the process. Platinum is formed directly in the membrane 550 in the cathode catalyst layer 540. As a preferable method, it can be manufactured simply by the adsorption-reduction method according to the prior art of the present inventors.

Example 1 of the Invention Electrolysis cell  >

1. Disinfectant Generation System

parameter value External power AC-DC Current Converter Current supply method With polarity switching cycle
Cycle: 1 hour (ta) -10 minutes (tc) Electrolysis cell Anode: Current Feeder 510-Iridium Oxide Catalyst Layer 520
-Oxidation of Iridium Chloride in Titanium Mesh
Membrane 550: Nafion117
Cathode: Membrane (550)-Platinum (540)
-Depositing electrode catalyst layer directly on the membrane

2. Operation condition of electrolyzer

parameter value Electrode area 4 cm ² Electrolyte Tap water (100 ppm Cl) water tank 1000 cc

3. Performance Analysis

parameter Analysis method Analysis interval (hours) result Voltage Measure with multimeter 1 hours Marked as Example 1 in FIG.
Marked as Example 2 in FIG. 8 Chlorine Concentration Iodine titration 1 hours Marked as Example 1 in FIG. Current efficiency Calculated by Equation 1 1 hours Marked as Example 1 in FIG.

(1) Measurement of current efficiency

The current efficiency is obtained by dividing the actual value of hypochlorous acid generated with respect to the applied current (I) by the theoretical value.

Current efficiency (%) = (F × ρ × V) / （35500 （mg） × I × t）｝ × 100 (Equation 1)

Where F is a Faraday constant 96500 (C), ρ is the actual residual chlorine concentration (ppm, mg / L), V is the amount of water supplied to the electrolysis cell (L), I is the conduction current (A), and t is the electricity Decomposition time (s).

(2) accumulation of Ca / Mg

It is determined whether Ca or Mg is accumulated from the voltage change of the electrolysis cell.

<Comparative Example 1-Existing Electrolysis cell  >

1. Disinfectant Generation System

parameter value External power Water generation system, AC-DC current converter Current supply method With polarity switching cycle
Cycle: 1 hour (ta) -10 minutes (tc) Electrolyzer Conventional Electrolysis Cell

2. Electrolysis Cell Structure

parameter value Anode and cathode electrodes Catalyst bed Ti plate-platinum coating Membrane-electrode Catalyst bed No membrane anode Catalyst layer  cathode Between catalyst beds  Street 3 mm

* Electrode catalyst layer coating method: pyrolysis method

3. Electrolyzer operation condition: same as Example 1

4. Performance Analysis

parameter Analysis method Analysis interval (hours) result Voltage Measure with multimeter 1 hours Marked as Comparative Example 1 in FIG. 6 Current efficiency Calculated by Equation 1 1 hours Marked as Comparative Example 1 in FIG.

<Comparative Example 2-Existing Electrolysis cell -No change in polarity period>

1. Disinfectant generation system: only Example 1 and current supply method is different.

parameter value External power AC-DC Current Converter Current supply method No polarity change cycle Electrolyzer Same as Example 1

2. Electrolysis cell structure: same as Example 1

3. Electrolyzer operation condition: same as Example 1

4. Performance Analysis

parameter Analysis method Analysis interval (hours) result Voltage Measure with multimeter 1 hours Marked as Comparative Example 2 in FIG. 8

<Review>

1. Improvement of voltage and current efficiency

6 and 7 show the performance-voltage and current efficiency of the electrolysis cell according to the present invention. Comparing Example 1 and Comparative Example 1 according to the present invention, the voltage of the electrolysis cell was 5.2 V in Comparative Example 1, 2.6 V in Example 1 according to the present invention, and Comparative Example 1 was 4 in the case of current efficiency. ~ 5%, the embodiment according to the present invention is 56%, it can be seen that the voltage and current efficiency is significantly improved.

2. Removal of calcium and magnesium accumulation

8 is a chart comparing the voltages of the electrolysis cell when the current applied to the electrolysis cell is converted (Example 2) and the existing current is not converted (Comparative Example 2). As calcium and magnesium accumulate on the electrode over time, the accumulated calcium and magnesium interfere with the flow of current, causing the voltage to rise. As shown in FIG. 8, while Comparative Example 2 continuously increased in voltage for about one month, Example 2 was found to operate very stably without a change in voltage.

100: electrolysis cell 110: anode
120: cathode 200: electrolysis cell system
210: external power supply 212: positive terminal
214: anode terminal 220: electrolysis cell
222: anode 224: cathode
300: disinfectant generation system 330: AC-DC current conversion unit
340: electrolysis cell 400: waveform of the generated current of the AC-DC current converter
500: electrolysis cell 510: anode current feeder
520: anode catalyst layer 530: cathode current feed
540: cathode catalyst layer 550: distance maintenance membrane

Claims (5)

In the disinfectant generating system consisting of an AC-DC current converter, an electrolysis cell,
The electrolysis cell is composed of a cathode current feeder, a cathode catalyst layer, a cathode current feeder, a cathode catalyst layer, and a membrane for maintaining the distance between the anode catalyst layer and the cathode catalyst layer,
The anode catalyst layer is composed of iridium oxide, the cathode catalyst layer is composed of platinum,
The anode catalyst layer is formed in the anode current feed, the cathode catalyst layer, characterized in that formed on the distance maintaining film, sterilant generating system. The method of claim 1,
Disinfectant generation system of the distance between the anode catalyst layer and the cathode catalyst layer is 10 ~ 200 ㎛. The method of claim 1,
The thickness of the distance maintaining film is 10 ~ 200 ㎛ sterilizer generating system. The method of claim 1,
The distance maintaining membrane is a non-electrically conductive, ionic conduction generating system is possible. The method of claim 1,
The current supplied from the AC-DC current converter to the electrolysis cell is supplied by crossing the current flowing from the cathode to the anode and the current flowing from the anode to the cathode,
The ratio Ac / Aa of the current value (Aa) flowing from the cathode to the anode and the current value (Ac) flowing from the anode to the cathode is 0.001 to 1, and the holding time (Ta) of the current flowing from the cathode to the anode and flowing from the anode to the cathode A sterilant generating system, wherein the ratio Tc / Ta of the holding time (Tc) of the current is 0.001 to 1, and the holding time (Ta) of the current flowing from the negative electrode to the positive electrode is 0.1 hour to 24 hours.

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