KR20090081930A - OH radical generator - Google Patents

Abstract

The present invention is an apparatus for generating OH radicals for oxidizing, decomposing and sterilizing by permeating air containing organic matter, forming an appearance, and an inlet end and an outlet end in which oxygen is introduced together with air on the front side and the rear side. Each having a housing coated with titanium dioxide on an inner circumferential surface and a hydrogen peroxide flowing into the inlet end from a hydrogen peroxide generator arranged to communicate with the inlet end while passing through the inside of the housing to expose the mixed air to the UV lamp. Disinfection, oxidation and sterilization while passing through the OH radicals generated between the titanium dioxide coating layer, the UV lamp is disposed in the housing so that clean air is discharged through the outlet, the sterilization was carried out in the previous single method Indoor volatility by having a far superior decomposition, oxidation and sterilization effect than the technique By removing organic substances, pollutants and pathogenic bacteria, and combining with air conditioning system such as sick house syndrome, it is possible to improve the indoor air quality at all times.

Description

OH radical generator

In the present invention, hydrogen peroxide is formed as an intermediate in the initial reaction stage in which ozone is photolyzed by ultraviolet energy using advanced oxidation method (UV / O3 = AOP) using ultraviolet and ozone in parallel, and the path of ultraviolet energy The present invention relates to an OH radical generating device through which OH radicals are generated.

Conventionally, it can be seen that there is a bactericidal effect on ultraviolet rays, such as sun exposure and airing so that moths do not lie. Ultraviolet disinfection mechanisms are not yet fully understood, but it is judged that the current nucleic acid (DNA) in the cell is changed by the irradiation, causing the metabolism to be impaired, and the proliferative ability is lost and decreased.

Such ultraviolet sterilization has the following characteristics.

1) Valid for all species.

2) Unlike sterilization by drugs or heating, it hardly changes the irradiated objects.

3) Simple to use and economical.

4) It is most suitable for sterilization of air or water. This is because most materials other than air and water are sterilized only on the irradiated surface.

5) The bactericidal effect is limited during the investigation and does not remain.

6) Ultraviolet rays are harmful to the eyes and skin, so care must be taken.

The bactericidal effect of ultraviolet rays is related to the wavelength and irradiation amount (radiation intensity x irradiation time) of ultraviolet rays. This is almost the same depending on the species, with the highest wavelength around 250-260 nm. In almost the same wavelength characteristics of the bactericidal effect, it is believed that ultraviolet rays are absorbed and changed by nucleic acids, which cause damage to metabolism and lose their proliferative capacity. The survival rate of bacteria is mostly exponentially reduced with respect to the amount of UV radiation (radiation intensity × irradiation time).

Thus, a method that is commonly used as a method for sterilizing air at room temperature is a short wavelength ultraviolet sterilization method, the ultraviolet region used here is a short wavelength of about 252nm, excellent sterilization power by high energy. However, the effect obtained is poor for sterilizing bacteria contained in the air due to poor permeability in the air, and particularly in the air containing a large amount of fine dust. Therefore, such a short wavelength ultraviolet sterilization method is mainly used for sterilization of tableware or the like requiring surface sterilization.

Here, looking at the photocatalytic reactor of titanium dioxide as follows.

TiO2-> e- + h + (1)

OH- + H +-> OH

Or H 2 O + h +-> OH + H +

O2 + e--> O2- (3)

Titanium dioxide absorbs ultraviolet rays having a wavelength of 380 nm or less to generate electrons (e-) and holes (h +) as shown in Equation (1). The resulting holes oxidize OH- ions or water on the titanium dioxide surface to produce hydroxyl radicals (OH ·) as in equation (2). The produced OH · is used to decompose and sterilize the organic matter in the aqueous solution. The electrons generated in the formula (1) reduce the incoming oxygen to produce superoxide (O2-), as shown in the formula (3). The produced O2- also exhibits strong bactericidal power.

Therefore, in the present application, as a result of intensive studies to solve the above problems, the titanium dioxide is coated on the inner surface of the housing, and the light in the wavelength region used for the photoreaction is longitudinally disposed in the center of the housing, The challenge is to derive an OH radical generating device that can effectively oxidize, decompose and sterilize pollutants such as VOC organic matter.

In order to achieve the above object, the OH radical generating device according to the present invention,

A device for permeating air containing organics to generate OH radicals for oxidation, decomposition and sterilization,

A housing having an inlet end and an outlet end in which oxygen is introduced together with air on the front side and the rear side, and having a titanium dioxide coating on the inner circumferential surface;

While passing through the housing, the hydrogen peroxide flowing into the inlet end is vaporized from the hydrogen peroxide generator disposed in communication with the inlet end, and the mixed air passes through the OH radicals generated between the titanium dioxide coating layer exposed to the UV lamp. UV lamps are disposed in the housing so as to be decomposed, oxidized and sterilized and discharged through the outlets.

In addition, the housing is preferably made of a configuration in which a plurality of tubes coated with titanium dioxide are arranged long along the longitudinal direction.

Moreover, it is preferable to employ | adopt 315-450 nm as the ultraviolet wavelength of the said UV lamp.

In addition, it is preferable to arrange the suction fan and the driving motor for air attraction inside the discharge end of the housing.

In addition, the inlet end of the housing is preferably arranged so that the strainer for filtering foreign matter.

In addition, it is preferable that the UV lamp is spaced apart from the inlet end so that the length of the distance between the inlet end of the housing and the tip of the UV lamp is greater than the distance between the inner wall of the housing and the mixing area in which hydrogen peroxide is mixed.

Hereinafter, an OH radical generating device according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a longitudinal cross-sectional view showing the internal structure of the OH radical generating device according to an embodiment of the present invention.

The present invention introduces "Application AOP System." 1. A.O.P (Advanced Oxidation Process) It is the world's first “Application A.O.P System” that combines photo-oxidation method and photo catalyst system.

Advanced oxidation using UV and ozone (UV / O3 = AOP) is called photooxidation. In this photooxidation method, hydrogen peroxide is formed as an intermediate in the initial reaction stage where ozone is decomposed by ultraviolet energy. It generates OH radical through.

OH radical increases UV, ozone decomposition, oxidation and sterilization power of organic substances by about 100 times.

Here, the removal reaction of the organic substance by the photooxidation method,

1. A pathway that is removed by reacting directly with ozone (O3),

2. the path removed by OH radical,

3. It is classified as a path of photolysis by ultraviolet rays (UV),

This can obtain a synergy effect that is 100 times higher than when ozone is used alone.

Oxidation of organic matter, such as air or water pollutants, by producing OH Radical as an intermediate product, is an excellent advantage of the AOP method and has much stronger oxidizing power than conventional oxidants such as chlorine, chlorine dioxide, and potassium permanganate. In addition, it can be applied to air or water treatment more economically and efficiently than using ozone alone.

An apparatus for generating OH radicals for permeating, containing, and oxidizing, decomposing and sterilizing air containing organic substances according to the present invention, wherein the ultraviolet rays used are ultraviolet rays having a long wavelength of 315 to 450 nm.

Titanium dioxide is coated with a synthetic resin tube or a housing by a gel-sol method and immobilized in a multilayer film in order to be affected by the ultraviolet rays in the above-described wavelength range.

In addition, the OH radical generating device 10 has an outer end and an inlet end through which oxygen is introduced together with air on the front side and the rear side, and an outlet end through which the oxygen is introduced, and the coating layer 3 coated with titanium dioxide on the inner circumferential surface thereof. Vaporized and mixed with the hydrogen peroxide flowing into the inlet end from the nozzle (41) -equipped hydrogen peroxide generator (40) disposed in communication with the inlet end while passing through the housing (1). UV lamp 2 so that air is decomposed, oxidized and sterilized through the OH radicals generated between the titanium dioxide coating layer exposed to the UV lamp 2 arranged by the support 4 and discharged through the outlet. ) Is arranged in the housing 1.

In the housing 1, one or more tubes 1a, 1b, 1c, ... coated with titanium dioxide are arranged along the longitudinal direction along with the UV lamp 2.

In addition, a suction fan 20 and a driving motor M for discharging air are disposed inside the discharge end of the housing 1.

In addition, a strainer 11 for filtering a foreign substance is disposed at the inlet end of the housing 1.

Further, the UV lamp 1 is introduced into the inflow end of the housing 1 and the end of the UV lamp 1 such that the length of the distance between the inner wall of the housing 1 or more is the mixing area 13 in which hydrogen peroxide is mixed. It is preferred to be spaced apart from the stage.

Ozone (O3) has strong oxidizing power and benefits such as THM production inhibition, taste, improvement of flocculation sedimentation and biological activity, but in fact, ozone has a slow reaction with most organic substances, , geosmin, saturated hydrocarbons such as MIB and THM, pesticides, etc.) It is pointed out that the reaction with organic matters is very selective, such as not reacting at all with organic matters. That is AOP (Advanced Oxidation Process) photooxidation method.

First, the mechanism of decomposition of organic matter during ozone oxidation is as follows.

In addition, the organic decomposition mechanism of A.O.P (photooxidation) system is as follows.

Next, OH Radical (OH-) will be described for understanding.

OH Radical, through the A.O.P method or the photocatalytic method, artificially decomposes ozone or produces photoreactive intermediates to produce highly reactive intermediate products. The resulting material is OH Radical.

OH Radical, which is called hydroxyl group, reacts with ozone molecules and decomposes, has a high potential difference (3.08V) through an intermediate path, and is characterized by uniform reaction with all organic materials at a very high speed. Its ability to decompose is 20 times more powerful than chlorine and 15 times more powerful than hydrogen peroxide, 2,000 times faster than ozone alone, and 180 times faster than UV alone.

Such OH Radicals are known as environmentally friendly substances that are harmless to the human body as pure natural substances while exhibiting powerful effects of oxidizing and decomposing various organic substances.

3. Types of A.O.P (Advanced Oxidation Process)

① Photolysis of Ozone: OZONE + UV (how UV is irradiated to ozone) (photooxidation method)

② Ozone + High pH (How to adjust pH in ozone)

③ Ozone + Hydrogen peroxide: PEROXONE (injecting hydrogen peroxide into ozone)

④ Photolysis of Hydrogen perozide: There are 4 types of methods, including PEROXONE + UV.

In addition, the photocatalyst in the photocatalyst system (photocatalyst) method refers to a catalyst in which photochemistry and a catalyst are combined and exhibit activity by light energy.

In general, the catalyst serves to control the rate of chemical change (chemical reaction) quickly or slowly without changing the catalyst itself.

Heat or other energy sources are used in chemical reactions. In the case of photocatalysts, light is used as the energy used in chemical reactions. When the light energy of sunlight or artificial light is irradiated to the catalyst, the catalyst absorbing the light energy is active to oxidize and reduce organic substances.

In addition, in the photocatalyst mechanism, the metal oxide is composed of a molecular orbital function composed of a valence band (VB) and a conduction band (CB). The difference between these two bands (E = ECB-EVB = hν) is called a band gap, and when the band gap energy is about 2.0 to 4.0 eV (electron volts), it shows the characteristics of the semiconductor. Representative photocatalysts among semiconductor compounds having a corresponding band gap energy difference include compounds such as TiO 2, ZnO, Fe 2 O 3, CdS, ZnS, and SnO.

When a semiconductor compound is irradiated with light having a wavelength equal to or greater than that of a band gap (315-450 nm), the light energy is absorbed to excite the electrons of VB to CB, and holes and electrons Occurs. Holes (hVB +) are formed in VB and excited electrons (e-CB) are formed in CB to form a hole + -e-pair (charge pair).

Holes oxidize moisture adsorbed on the surface of the catalyst to produce oxidative hydroxy radicals (OH-) or directly oxidize adsorbed organics.

Electrons in the conduction band generate superoxide O2- by giving electrons to the adsorbed oxygen, and the produced O2- oxidizes with organic matter or water. In the case of titanium dioxide (TiO 2), the excitation light has a wavelength of 380 nm or less corresponding to 3.2 eV for an anatase type and 415 nm or less corresponding to 3.0 eV for a rutile type. It refers to a catalyst in which these holes and electrons diffuse and move to the surface of TiO2 to react with a substance adsorbed on the surface. Recently, the treatment of sick house syndrome using the photocatalytic method and the improvement of the air quality of the room 100 have limited natural light (sun) that may affect the room, and the ultraviolet ray (300 nm or more) is constantly applied in an artificial manner. In order to irradiate the room 100, the effect on the human body is too dangerous because it is directed.

If the photocatalyst (Tio2, etc.) can always be photoreacted in the room 100 by visible light (ultraviolet light from fluorescent or incandescent lamps), there is no clear way to remove harmful substances, but unfortunately still The lack of a catalyst that can react to light is a limitation of today's technology.

Currently, the research is being actively conducted, but I think it is a task to be solved and homework. Therefore, the strong ultraviolet-free photocatalyst which is a condition of photoreaction is nothing but a useless thing.

The A.O.P method, the following three methods, namely

① Photolysis of Ozone: OZONE + UV (How to irradiate ozone with ultraviolet light (photooxidation method)

③ Ozone + Hydrogen peroxide: PEROXONE (injecting hydrogen peroxide into ozone),

④ Photolysis of Hydrogen perozide: PEROXONE + UV.

After applying the new AOP method by applying the new method, the photo catalyst system (photocatalyst) method is further added to create (Ozone + UV) + (Hydrogen peroxide + UV + Ozone) + (Tio2 + UV). Can be.

This is the "Application A.O.P System" developed through groundbreaking and original attempts.

In addition, the theoretical principle and form of equipment according to the development method of "Applied AOP System" are as follows.

First, the principle of the applied AOP system equipment is as follows.

Photolysis of Ozone of AOP (Advanced Oxidation Process): OZONE + UV AOP (Ozone UV irradiation method) and Ozone + Hydrogen peroxide: PEROXONE AOP (Injection of hydrogen peroxide into ozone), Photolysis of Hydrogen perozide: By combining PEROXONE + UV. (Hydrogen peroxide irradiation method) and TiO2 + UV of Photo catalyst system (photocatalytic method), the two methods are combined to reduce the amount of ozone (O3) that is a disadvantage in AOP. In addition, through direct irradiation of strong ultraviolet light (315 ~ 450nm), which is a defect in the photo catalyst, the catalyst can be sufficiently reacted to UV, thereby maximizing the production of the common purpose OH Radicals of the two processes.

On the other hand, the operating sequence of the system for understanding the applied AOP system equipment is as follows.

(1) Inhale oxygen from the atmosphere into the equipment.

(2) TiO 2 + UV. UV + O3. Pass the equipment manufactured according to the principle of UV + O3 + H2O2.

(3) Spray and spray the strong OH Radical, O3, etc. generated in the equipment to the room 100.

(4) Photooxidation and photolysis of harmful substances such as volatile organic compounds (TVOC) and formaldehyde (HCHO) generated in the room 100 and completely sterilization and removal of viruses and pathogenic bacteria.

(5) After exhausting the oxidized and decomposed residual material through ventilation, the room 100 immediately returns to a comfortable state.

The present invention does not require a suction fan since the air can be circulated only by a forced circulation device of the air conditioning system itself when the air conditioning system 30 is combined.

In the present invention, the housing 1 to which titanium dioxide is coated is most suited to Pyrex because the wavelength range of light transmitted along the tube is different. Quartz transmits light of about 252nm, which is suitable for sterilization using short wavelengths, and glass transmits light of about 400nm. Pyrex, on the other hand, transmits light in the 315-450 nm region.

The gel-sol method is used as a method of covering the housing 1 with titanium dioxide used as a photocatalyst in the air sterilization method according to the present invention.

This method is a coating treatment method in which the substrate is immersed in a sol-like solution of the inorganic powder to be coated on the housing 1, followed by gelation by removing the substrate by heat treatment at a constant tensile rate. It is important to prevent gelation of the sol solution when the inorganic powder is coated on the housing 1 by using such a treatment method. In the coating treatment of titanium dioxide, nitric acid solution is used as the gelling inhibitor, or tetrachloride is primarily used as the gelling inhibitor. Using titanium, an additional ethyl acetone acetate was added to prevent gelation double.

The method of coating titanium dioxide on the housing 1 will be described in detail in steps as follows.

[Production of Sol Solution of Titanium Dioxide]

Titanium-isopropylate (Ti [OCH (CH3) 2] 4) is dissolved in ethanol and then titanium tetrachloride (TiCl4) is added thereto to prevent gelation of the solution. Ethyl acetone acetate is added to this as an anti-gelling agent and the mixture is sufficiently stirred, followed by stirring with ethanol and water gradually added to obtain a clear sol solution.

Add ethylene glycol if the solution is less transparent or if you want to preserve the solution for a long time.

[Titanium Dioxide Coating]

After the housing 1 or the substrate to be coated is washed well with acetone or the like, dried and soaked in a titanium dioxide sol solution, the tensile speed is adjusted to 7 to 13 cm / min and stretched over the water surface. At this time, the coating thickness of titanium dioxide is 85 to 140 nm. In order to make the coating thicker than this, the coating treatment and the heat treatment process were repeated two or three times after the heat treatment process after the coating treatment, thereby forming a double multilayer film to increase the coating thickness. The coating thickness of titanium dioxide was measured using an indirect measurement method by optical interference using a refractive index difference using an Elso-meter model Auto EL-II (manufactured by Rudolph, USA).

[Heat treatment [gelation of titanium dioxide]]

As described above, the housing 1 or the substrate coated with titanium dioxide is naturally dried at room temperature for at least 3 hours, and then heat-treated at 300 ° C to 500 ° C. At this time, the organic substances contained in the coating are incinerated and removed. The heat-treated housing 1 is cooled to room temperature and used.

The Parylene tube coated with titanium dioxide prepared according to the manufacturing method of the present invention can transmit light of 320 nm to 12 μm, and thus can effectively use light of UV 315 to 450 nm effective for photoreaction with titanium dioxide. have. Therefore, it is possible to increase the efficiency of light, thereby increasing the sterilization effect. This effect is confirmed through the following test example.

In the OH radical generating device according to the present invention, an ultraviolet housing (1) is installed in a housing (1) coated with titanium dioxide prepared by the above-described process, or when using a pyrex plate, a plurality of pyrex plates are formed in a box shape. When the ultraviolet housing 1 is installed inside the ultraviolet ray to irradiate ultraviolet rays, the aqueous solution to be treated is sterilized by contacting the housing 1 or the outside of the box.

Hereinafter, the present invention will be described in more detail with reference to non-limiting examples of the present invention.

Example 1

After dissolving 568.5 g of titanium-isopropylate (TIPT) in 737.1 g of ethanol, 64.5 g of titanium tetrachloride and 130 g of ethyl acetone acetate were added thereto, followed by sufficient stirring. To the obtained sol solution, a mixed solution of 1105.7 g of ethanol and 144 g of water was added and stirred sufficiently to obtain a transparent sol-like titanium dioxide solution.

On the other hand, the housing 1 was washed well with acetone and dried. The housing 1 was immersed in the transparent sol solution and pulled up at a speed of 13 cm / min. This was naturally dried at room temperature for 3 hours, and then heat-treated at 400 ° C. for 2 hours to obtain a housing 1 coated with titanium dioxide having a thickness of 140 nm.

Thus prepared several housings 1 coated with titanium dioxide were arranged in parallel, and ultraviolet rays were installed inside the housing 1 to sterilize by contacting the aqueous solution while shining light.

Example 2

The Pyrex plate was washed well with acetone and then immersed in the solution of the titanium dioxide sol phase prepared in Example 1, followed by pulling up at a speed of 13 cm / min. This was naturally dried at room temperature for 3 hours and then heat-treated at 400 ° C. for 2 hours to obtain a Pyrex plate coated with titanium dioxide having a thickness of 140 nm.

The pyrex plates manufactured as described above were made into cylindrical shapes, and ultraviolet housings (1) and (2) were installed in the cylindrical housings (1) and oxidized, decomposed, and sterilized by passing air through the inside while shining light.

As a test example, the treated air was passed through the OH radical generator at a flow rate of 1 L / min for 3 seconds to decompose, oxidize and sterilize, and one of them was not oxidized, decomposed and sterilized as a control. At this time, the temperature of the treated water was 19 ℃ before treatment, 19.2 ℃ after treatment.

At this time, the number of bacteria was determined to be almost dead after the number of cells after incubation for 30 days at 30 ℃ by applying to the following Endo medium, YM medium, Neutrient medium.

Therefore, it has much better decomposition, oxidation and sterilization effect than the sterilization method performed by the previous single method, and removes volatile organic substances, contaminants and pathogenic bacteria, etc., and integrates them with air conditioning system such as sick house syndrome. It is possible to derive a very excellent effect such as to improve the indoor air quality.

As described above, it can be seen that excellent oxidation, decomposition and sterilization effects can be obtained when oxygen is added and at the same time using a long wavelength ultraviolet ray and the titanium dioxide is coated on the housing and used as a photocatalyst.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

1 is an internal structure showing an OH radical generating device according to an embodiment of the present invention,

2 is an internal structural view showing an OH radical generating device according to a second embodiment of the present invention, and

Figure 3 is a schematic structural diagram showing a state in which the OH radical generating device according to the third embodiment of the present invention is used in conjunction with the air conditioning system.

<Description of Signs of Major Parts of Drawings>

   1 ... housing 2 ... UV lamp

   3 ... titanium dioxide coating layer 4 ... support

  11 ... strainer 20 ... suction fan

  40 ... hydrogen peroxide generator 41 ... nozzle

Claims (6)

A device for permeating air containing organics to generate OH radicals for oxidation, decomposition and sterilization, A housing having an inlet end and an outlet end in which oxygen is introduced together with air on the front side and the rear side, and having a titanium dioxide coating on the inner circumferential surface; While passing through the housing, the hydrogen peroxide flowing into the inlet end is vaporized from the hydrogen peroxide generator disposed in communication with the inlet end, and the mixed air passes through the OH radicals generated between the titanium dioxide coating layer exposed to the UV lamp. And an UV lamp disposed in the housing so as to be decomposed, oxidized and sterilized so that clean air is discharged through the outlet. The method of claim 1, The OH radical generating device, characterized in that a plurality of tubes coated with titanium dioxide in the housing is arranged long along with the individual UV lamp along the longitudinal direction. The method of claim 2, Ultraviolet wavelength of the UV lamp is 315 to 450 nm, characterized in that the OH radical generating device. The method of claim 3, wherein An OH radical generating device, characterized in that a suction fan and a drive motor for air attraction inside the discharge end of the housing is disposed. The method of claim 4, wherein An OH radical generating device, characterized in that a strainer is disposed at the inlet of the housing to filter foreign matter. The method of claim 5, wherein And the UV lamp is spaced apart from the inlet end such that a mixing area in which hydrogen peroxide is mixed is formed between the inlet end of the housing and the tip of the UV lamp.

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