KR20030020860A - Preparation of photocatalytic thin film and water-treatment apparatus using thereof - Google Patents

Abstract

PURPOSE: A method for preparation of a photocatalyst thin film with high activity and strong adherence on substrate, and a water treatment apparatus using the photocatalyst thin film are provided to sterilize germs and oxidize recalcitrant toxic compounds such as agricultural chemicals and trihalomethane in wastewater/sewage. CONSTITUTION: The method for preparation of a photocatalyst thin film with high activity and strong adherence on substrate includes the steps of (a) mixing 1 to 50 wt.% of titanium-based inorganic binder, 0.1 to 30 wt.% of organic solvent and 0.01 to 5 wt.% of inorganic acid, followed by agitation for 0.1 to 10 hrs; (b) mixing 1 to 30 wt.% of organic polymer and 5 to 50 wt.% of organic solvent; (c) mixing a resultant from the first step with a resultant from the second step, followed by agitation for 0.5 to 10 hrs; (d) adding 1 to 30 wt.% of chelator, 0.001 to 5 wt.% of surfactant and 0.1 to 10 wt.% of photocatalyst powder to the resultant from the third step, followed by ultrasonication for 0.1 to 10 hrs to prepare a photocatalyst sol; (e) coating the photocatalyst sol on a substrate by dip coating or spray coating method; (f) drying the coated substrate at 50 to 450 deg.C for 0.1 to 50 hrs; and (g) heat treating the dried substrate at 120 to 650 deg.C for 0.1 to 50 hrs. The photoreactor comprises a hollow quartz tube (14) on the outer surface of which photocatalyst thin film is formed; an ultraviolet lamp (10) which is installed inside the hollow quartz tube to generate light; a socket (8) which supplies electric current to the ultraviolet lamp.

Description

Preparation method of photocatalyst thin film and water treatment apparatus using same {Preparation of photocatalytic thin film and water-treatment apparatus using example}

The present invention relates to a photocatalyst coating sol and its use, and more particularly, to preparing a photocatalyst coating sol including a titanium-based inorganic binder, a photocatalyst powder, a polymer organic compound, an organic solvent, and the like, and then the photocatalyst coating. The present invention relates to a method for manufacturing a photocatalyst device having good light transmittance, photoactivity and durability by coating a surface of a substrate by spraying or dipping and then heat treatment to form an anatase crystal thin film having excellent photoactivity.

Recently, due to industrial development, toxic and inorganic substances are continuously released into waste water or waste gas due to industrial development, and numerous processes for removing these toxic substances have been researched and developed over the years. Among these processes, there are methods of using adsorbents, biological treatments, and catalysts, but adsorbents have secondary pollution problems that require treatment of concentrated adsorbents, and biological treatments are difficult to decompose. Unsuitable for the treatment of materials. In addition, the method using the catalyst generates economic problems due to the expensive precious metal catalyst and the high operating cost.

Recently, in order to solve the above-mentioned problems, there is increasing interest in a method of removing contaminants and odorous substances using a photocatalytic oxidation reaction, which is one of advanced oxidation techniques.

Here, the photocatalytic oxidation reaction generates electrons and holes when light energy of more than a band gap energy is irradiated to the photocatalyst, and is adsorbed on the surface of the photocatalyst by the strong oxidizing power of radicals (· OH) generated by the holes. Refers to a reaction in which the organic or liquid organic matter is oxidized and decomposed.

In general, as a technique for forming a thin film by coating a photocatalyst on the surface of the substrate, a nanometer-sized titania powder such as microparticles obtained from hydrolysis of titanium tetrachloride or using Degussa P-25 as a photocatalyst in a silane-based inorganic binder is used. This method is mainly used. However, when the above-described powder type photocatalyst is used, the silane-based inorganic binder for fixing the photocatalyst powder has a disadvantage in that the photocatalyst surface is coated to lower the photoactivity.

In addition, there is a method of coating a titanium-based compound such as titanium nitrate, titanium sulfate, and the like by using an inorganic binder, but low light activity and low adhesion to a substrate often cause peeling of the coated thin film.

For this reason, the above-described coating technology is mainly used for purifying the air rather than being applied to a water treatment device due to a problem of low light activity or low durability.

On the other hand, conventional photocatalysts for water treatment such as sewage are classified into a fluidized bed photocatalyst device in which a photocatalyst is immobilized on a substrate such as a photocatalyst, glass beads, or ceramic, and a fixed bed photocatalyst device in which the photocatalyst is immobilized inside the device.

Among the fluidized bed photocatalysts, the double-tube reactor using the photocatalyst as the suspended phase has the best photoactivity, but since the method is configured to recover and recycle the photocatalyst, the system configuration such as the photocatalyst fine particle separation device and the circulator is very complicated. It is not suitable for treating a large amount of sewage, and there are problems such as lack of economy due to a very expensive device cost.

In addition, in order to improve the problem of recovering the photocatalyst, an apparatus using a photocatalyst by immobilizing the photocatalyst on a substrate such as glass beads, ceramics, etc. has been developed. However, the method is less likely to come into contact with ultraviolet light required for the photocatalytic oxidation reaction. There are problems such as lowering and being unsuitable for treating a large amount of sewage.

On the other hand, the stationary phase photocatalyst is mainly used by immobilizing the photocatalyst on a substrate such as glass, ceramic, quartz, or metal having various shapes such as spherical, tubular, rod, plate, and disc as a stationary phase by sol-gel method or impregnation method. To achieve.

As an example, Korean Patent Publication No. 2001-0007771 discloses a photocatalyst device in which a titanium dioxide sol, which is a photocatalyst, is coated with glass beads, porous glass beads, metal beads, silicates, or the like by dipping or spraying. 0008324 describes a water treatment apparatus in which nanoparticle-sized titanium dioxide is coated on substrates such as glass, zeolite and activated carbon.

However, the above-described fixed-phase photocatalyst device has a problem in that it is impossible to obtain substantially the desired photoactivity due to ultraviolet characteristics having a short wavelength band of 200 to 400 nm, which is very short in penetration distance from several mm to several cm in water.

In order to overcome the above-mentioned problems, various types of reflective surfaces are provided in the water, and a UV lamp is installed on the surface of the water to irradiate the reflective surfaces provided in the water. The rotating member is installed in the water by the submersion type, and a method of installing an ultraviolet lamp on the water has been developed. However, there is a limit to increasing photoactivity by the above-described method.

All of the above-mentioned conventional photocatalytic oxidation systems have not been commercialized to date because there is no suitable photocatalyst thin film coating method capable of satisfying all conditions that the photocatalyst thin film should have excellent light transmittance, adhesion to the substrate, and excellent photoactivity.

The present invention is to overcome the above problems, and provides a photocatalyst coating sol comprising a titanium-based inorganic binder, a photocatalyst powder, an organic solvent, an inorganic acid, a high molecular organic compound, and the like, and a manufacturing method thereof.

In addition, the present invention is to sterilize bacteria and microorganisms present in filthy water by coating the photocatalyst coating sol on a transparent substrate by spraying or dipping, or to oxidize and decompose various organic compounds including toxic and hardly decomposable organic substances. Provided is a water treatment device.

1 is a block diagram of a water treatment apparatus according to the present invention,

2 is a block diagram of a photocatalyst device according to the present invention;

3 is a perspective view of a water treatment system equipped with a water treatment apparatus according to the present invention;

4 is a cross-sectional view of a water treatment system equipped with a water treatment apparatus according to the present invention.

<Description of the symbols for the main parts of the drawings>

2: water treatment device 4: support stand

6: photocatalyst device 8: socat

10 lamp 12 photocatalyst thin film

14 quartz tube 16 power supply member

18: water treatment system 20: inlet

22 outlet 24: switchboard

26: terminal box 28: top plate

30: partition 32: reactor

In one aspect, the present invention is 0.1 to 10% by weight photocatalyst powder, 1 to 50% by weight titanium-based inorganic binder, 5 to 80% by weight organic solvent, 1 to 30% by weight high molecular organic compound and inorganic acid per total photocatalyst coating sol solution It provides a photocatalyst coating sol comprising 0.01 to 5% by weight.

In another aspect, the present invention is 0.1 to 10% by weight photocatalyst powder, 1 to 50% by weight titanium-based inorganic binder, 5 to 80% by weight organic solvent, 1 to 30% by weight organic polymer compound, inorganic acid per total photocatalyst coating sol solution It provides a photocatalyst coating sol comprising 0.01 to 5% by weight, chelating agent 1 to 30% by weight and / or 0.001 to 5% by weight surfactant.

In another aspect, the present invention is mixed with 1 to 50% by weight of the titanium-based inorganic binder and 0.1 to 30% by weight of the organic solvent per sol solution for the total photocatalyst coating, 0.1 to 5% by weight of the inorganic acid is added to the mixture 0.1 Reacting with stirring for 10 hours; Mixing 1 to 30 wt% of the polymer organic compound and 5 to 80 wt% of the organic solvent; Adding the polymer organic compound and the organic solvent mixture to the finished product of the reaction and reacting with stirring for 0.1 to 10 hours; After the stirring is completed, the method provides a photocatalyst coating sol comprising the step of dispersing the photocatalyst powder for 0.1 to 10 hours using an ultrasonic apparatus after adding 0.1 to 10 wt% of the photocatalyst.

In another aspect, the present invention is coated with a photocatalyst coating sol on the outside of the substrate by spraying or immersion method and then dried at 50 to 450 ℃ for 0.1 to 50 hours, the dried substrate is 0.1 to 50 at 120 to 650 ℃ It provides a method for producing a photocatalyst thin film comprising a heat treatment for a time.

In still another aspect, the present invention provides a plurality of photocatalyst devices including an ultraviolet lamp for generating light inside a substrate on which the photocatalyst thin film is formed, and supplies a current to a lamp provided inside the substrate on which the photocatalyst thin film is formed. It provides a water treatment apparatus including a power supply member for.

Photocatalysts constituting the photocatalyst powder according to the present invention are generally photoactive metal oxides, that is, TiO ₂ , ZnO ₂ , ZnO, CaTiO ₃ , WO ₃ , SnO ₂ , MoO ₃ , Fe ₂ O ₃ , InP, GaAs, BaTiO ₃ , KNbO ₃ , Fe ₂ O ₃ , Ta ₂ O ₅ and Degussa P-25 [Degussa, Germany] may be used alone or in combination of two or more, preferably TiO ₂ and / or ZnO, Especially preferred is Degussa P-25 [Degussa, Germany]. In addition, the smaller the particle size of the photocatalyst powder is, the more excellent the photocatalytic activity is, so the average diameter of the particles is preferably 1 to 10000 nm, preferably 5 to 50 nm.

On the other hand, the reaction rate of the photocatalyst is increased by adding a metal or a metal oxide, for example, palladium, platinum, radium, tungsten, gold, silver and copper, the additive is 0.01 to per total photocatalyst weight 5% by weight may be added and used.

In addition, the photocatalyst powder according to the present invention is included in the photocatalyst coating sol as a dispersed phase to serve as a seed during the heat treatment of the photocatalyst thin film, and the phase transition temperature of the titanium-based inorganic binder to the anatase phase is lowered so that the heat treatment temperature To lower the, it is possible to manufacture a uniform particle size of the titanium-based inorganic binder is changed to the anatase phase can be maximized the light activity.

When the titanium-based inorganic binder according to the present invention is coated on a substrate and thinned, the titanium-based inorganic binder serves as a binder to increase the bonding force between the photocatalyst and the substrate and also serves as a photocatalyst having excellent photoactivity.

Here, the term "substrate" refers to an object to which the photocatalyst coating sol is coated according to the present invention, and is used by thin film coating of the photocatalyst coating sol on the surface of the substrate by immersion or spray method. When the photocatalyst thin film is formed on the surface of the substrate, when light such as ultraviolet rays is irradiated, it exhibits photoactivity. Therefore, the substrate is generally preferred to be transparent so that the ultraviolet light can pass through, and can be used in the water treatment device by coating the sol for the photocatalyst coating, for example, any of glass, quartz, metal, plastic, etc. You may make it, Preferably quartz is preferable.

As a material which can be used as a titanium-based inorganic binder having the above-mentioned characteristics, a material which has photoactivity when irradiated with light and which can be easily combined with a substrate as a binder, for example, titanium alkoxide type such as titanium isopropoxide titanium butoxide, etc. Any compound may be used, and titanium isopropoxide is preferable.

Herein, the titanium-based compound, which is the titanium-based inorganic binder, is crystallized in the heat treatment process for forming the photocatalyst thin film and is converted into an anatase phase having excellent photoactivity, so that the binder itself has a photocatalytic function.

The polymer organic compound according to the present invention is to increase the adhesion and specific surface area of the photocatalyst thin film prepared by using a photocatalyst coating sol, and is oxidized and decomposed during the heat treatment process to form the photocatalyst thin film, thereby leaving no residue. The specific surface area is improved, and the adhesion of the resulting photocatalyst thin film is improved to prevent peeling from occurring, and at the same time, a photocatalyst thin film having excellent durability is manufactured.

Examples of the polymer organic compound that can be used include hydroxypropyl cellulose, polyethylene glycol, polyvinyl alcohol, and the like, and hydroxypropyl cellulose is preferable.

The inorganic acid according to the present invention is for controlling the hydrolysis rate of the titanium-based inorganic binder having the photocatalyst, and examples of usable materials include sulfuric acid, nitric acid, hydrochloric acid, and the like.

As the organic solvent according to the present invention, an alcohol having a lower alkyl group, for example, ethyl alcohol, methyl alcohol, butyl alcohol, secbutyl alcohol, propyl alcohol, isopropyl alcohol or isopropanol may be used.

Referring to the manufacturing method of the photocatalyst coating sol comprising the above configuration as follows.

Iii) 1 to 50% by weight of the titanium-based inorganic binder and 0.1 to 30% by weight of the organic solvent are mixed per total photocatalyst coating sol solution, and 0.01 to 5% by weight of the inorganic acid is added to the mixture, followed by stirring for 0.1 to 10 hours. Reacting;

Ii) mixing 1 to 30% by weight of the polymer organic compound and 5 to 50% by weight of the organic solvent;

Iii) adding the mixture prepared in step ii) to the product prepared in step iv) and reacting with stirring for 0.1 to 10 hours;

Iii) adding 0.1 to 10% by weight of the photocatalyst to the product of step iv) and sonicating for 30 to 10 hours in an ultrasonic apparatus.

Meanwhile, in step iii), if necessary, 1 to 30% by weight of chelating agent and / or 0.001 to 5% by weight of surfactant may be further added, followed by sonication in an ultrasonic device to prepare a photocatalyst coating sol.

In this case, the chelating agent is usually used to stabilize the reactants, the usable material is preferably ketones, preferably acetone or acetylacetone.

The surfactant is used for the purpose of improving the fluidity of the photocatalyst coating sol, and any surfactant that can achieve the above object can be used, but it is recommended to use BYK-300 [BYK Chemi, Germany] Good to do.

The photocatalyst coating sol prepared as described above is coated on the surface of the substrate constituting the water treatment apparatus to be applied to a water treatment apparatus for treating sewage and the like to form a thin film.

As a method of coating the above-described photocatalyst coating sol on a desired substrate, a method of coating, drying, and heat treatment after printing, spraying, or dipping may be used. good. Here, the drying process of the spray method and the immersion method is 0.1 to 50 hours at 50 to 450 ℃, the heat treatment process is carried out for 0.1 to 50 hours at 120 to 650 ℃.

On the other hand, the photocatalyst powder contained in the photocatalyst coating sol serves as a seed in the process of forming the thin film, the photocatalyst is present in the form of a seed in the photocatalyst coating sol to reduce the crystallization temperature to heat treatment of the heat treatment process The temperature can be kept lower than the conventional heat treatment temperature for heat treatment at a temperature of 500 to 600 ℃, and the particle size of the titanium-based inorganic binder formed on the thin film can be kept uniform and small to maximize the optical activity and increase the transparency of the thin film. have.

In addition, the heat treatment process crystallizes the titanium-based inorganic binder according to the present invention, and converts it into an anatase phase with excellent photoactivity, thereby maximizing photoactivity with the photocatalyst when light is irradiated on the photocatalyst thin film. A titanium-based inorganic binder, that is, a titanium-based inorganic binder converted to titania on an anatase itself has a photocatalytic function with excellent photoactivity.

In addition, in the present invention, the titanium-based inorganic binder and the photocatalyst powder having photoactivity by adding a polymer organic compound to the photocatalyst coating sol are more strongly attached to the substrate, and are all oxidized and decomposed in the heat treatment step so that they do not remain in the photocatalyst thin film. Therefore, the specific surface area of the photocatalyst thin film is improved.

Therefore, when the photocatalyst thin film is formed on the substrate using the photocatalyst coating sol according to the above method, when light is irradiated to the photocatalyst thin film, the synergistic effect of the photocatalyst component and titanium-based inorganic binder included in the photocatalyst thin film is very significant. Since it has excellent photocatalytic activity, it is possible to prevent photocatalytic coating phenomenon and photoactivity deterioration caused by the conventional silane-based inorganic binder, and to maximize adhesion to the substrate.

Meanwhile, in the step of coating the photocatalyst sol on the substrate using the spray method or the immersion method, 0.001 to 5% by weight of the surfactant may be added per weight of the total photocatalyst sol to improve the fluidity of the photocatalyst sol.

Hereinafter, a quartz catalyst coated with a photocatalyst will be described as an example of manufacturing a water treatment device using the photocatalyst sol solution according to the present invention with reference to the drawings.

1 is a block diagram of a water treatment device according to the present invention, FIG. 2 is a block diagram of a photocatalyst device according to the present invention, FIG. 3 is a perspective view of a water treatment system equipped with a water treatment device according to the present invention, and FIG. It demonstrates together as sectional drawing of the water treatment system equipped with a water treatment apparatus.

1 and 2, the water treatment device 2 according to the present invention is a photocatalyst thin film 12 is formed by coating a photocatalyst coating sol on the outer surface of the transparent hollow hollow quartz tube 14, At least one lamp 10 for irradiating light to the photocatalyst thin film 12 is provided inside the quartz tube 14 and includes a socket 8 for supplying current to the lamp 10. At least one photocatalyst 6 and a socket 8 provided at left and right ends of the photocatalyst 6 are inserted into a support 4 for fixing the photocatalytic device 6, and at an upper end side of the support 4; Connected to the upper plate 28 to secure the support (4), the terminal box 26 is connected to the socket (8) of the photocatalyst device 6 to supply current and the power supply member for supplying current to the terminal box (16).

Here, the support (4) is provided in pairs on the left and right, the left and right support (4) is in the form of a "c" opening upwards, to the top of the "c" opening upwards The upper plate 28 is configured in a form that is connected.

However, since the shape of the support 4 can be changed in various ways depending on the position of the photocatalyst 6, the support 4 is not limited to the upwardly open "C" shape. For example, when the photocatalyst 6 is formed vertically, the photocatalyst 6 is provided with the position of the support 4 on which the socket 8 of the photocatalyst 6 is inserted and fixed. ) Can be fixed.

Looking at the operation of the water treatment device 2 having the above-described configuration is as follows.

When a current is applied to the power supply member 16 of the water treatment device 2, the current passes through the terminal box 26 of the water treatment device 2 and changes to a current and voltage suitable for operating the lamp 10, The changed current and voltage are transmitted to the lamp 10 through the socket 8 constituting the photocatalyst 6 so that light is generated from the lamp 10, and the generated light is quartz of the photocatalyst 6. When the light is irradiated to the photocatalyst thin film 12 formed on the surface of the quartz tube 14 by passing through the tube 14, the photocatalytic oxidation is performed on the surface of the photocatalyst thin film 12. A reaction occurs, and the photocatalytic oxidation oxidizes contaminants present in the sewage flowing through the water treatment device 2.

At this time, the photocatalyst thin film constituting the photocatalyst thin film 12 has the entire photocatalyst activity by the light irradiated from the lamp 10.

On the other hand, when the sewage treatment using the water treatment device 2 having the above configuration as shown in Figures 3 and 4, a plurality of water treatment device 2 is installed in one reactor 32 The water treatment system 18 can be configured.

The water treatment system 18 is provided at one side of a predetermined reaction tank 32 to install the inflow port 20 into which the sewage flows, and is installed vertically with respect to the reaction vessel 32 in the longitudinal direction. At least one or more partitions 30 to sequentially flow from the top, a water treatment device 2 disposed between the partitions 30 to remove contaminants present in the sewage, and the respective water treatment devices 2 A distribution panel 24 connected to the terminal box 26 to supply current, and installed at one side of the power supply member 16 and the reaction tank 32 connected to the distribution panel 24 to supply current. It consists of an outlet 22 which passes the water treatment apparatus 2 along the 30, and discharges the treated water.

Looking at the operation of the water treatment system 18 having the above-described configuration as follows.

First, when sewage flows into the inlet 20 provided at one side of the reaction tank 32 of the water treatment system 18, current is supplied to the power supply member 16 to supply current to the switchboard 24, and the switchboard. The current supplied to the 24 is transferred to the terminal box 26 provided in each of the water treatment devices 2, and then to the socket 8 of the photocatalyst device 6 connected to each of the terminal boxes 26, so that the lamp ( 10) light is generated.

Then, the generated light is irradiated to the photocatalyst thin film 12 formed on the surface of the quartz tube 14 through the quartz tube 14 of each photocatalyst 6, and the photocatalyst thin film 12 When light is irradiated), photocatalytic oxidation occurs on the surface of the photocatalyst thin film 12.

On the other hand, the sewage flowing into the reaction tank 32 of the water treatment system 18 flows up / down or down / up along the partition walls 30 provided between the respective water treatment apparatuses 2 to show the photocatalytic activity. It is conveyed in contact with the photocatalyst device 6 of the water treatment device 2.

Subsequently, contaminants in the wastewater contacting the photocatalytic device 6 are oxidatively decomposed by a photocatalytic oxidation reaction of the photocatalyst thin film 12 formed on the surface of the photocatalytic device 6, and the respective water treatment devices 2 The treated water is moved along the partition wall 30 provided between the discharged to the outside through the outlet 22 provided on the other side of the inlet 20 opposite.

Here, the water treatment apparatus 2 and the water treatment system 18 using the photocatalyst described above can be variously applied not only for air purification but also for water treatment, and are particularly suitable for water treatment.

Therefore, the application of the water treatment system 18 using the photocatalyst according to the present invention is installed in waterways in the case of water and sewage treatment facilities to sterilize bacteria and microorganisms, and toxic and hardly degradable organic compounds such as pesticides and trihalomethane. It can oxidatively decompose, sterilize various kinds of filthy water such as industrial wastewater, leachate and oxidative decomposition of various organic compounds.

In addition, those skilled in the art will readily recognize that safe sterilization of drinking water or contamination by algae such as green algae and red tide in rivers and lakes can be easily solved.

Hereinafter, the present invention will be described in detail through examples. However, the following examples are only for illustrating the present invention in detail and are not intended to limit the scope of the present invention by these examples.

<Example 1>

0.1 g of nitric acid was added dropwise while reacting for 2 hours while mixing 30 g of titanium isopropoxide [Great Gold, Korea] and 50 g of isopropyl alcohol [Great Gold, Korea].

Then, 10 g of hydroxypropyl cellulose [Aldrich, USA] was dissolved in 30 g of isopropyl alcohol, mixed with the product produced by the reaction, and then reacted with stirring for 1 hour.

After the reaction was completed, 3g photocatalyst P-25 [Degussa, Germany] was added, and then treated with an ultrasonic device Tip-sonicator for 1 hour to prepare a photocatalyst coating sol. For coating, 0.05 g of BYK-300 [BYK Chemi, Germany] was added as a surfactant to coat the surface of a quartz tube having a length of 1000 mm, an inner diameter of 25 mm and an outer diameter of 28 mm by immersion. The quartz tube coated with the immersion method was dried at 200 ° C. for 30 minutes and heat-treated at 450 ° C. for 2 hours.

<Example 2>

In the same manner as in Example 1, but instead of hydroxypropyl cellulose polyethylene glycol [Duksan, Korea] was used to prepare a photocatalyst coating sol and thin film.

<Example 3>

In the same manner as in Example 1, using a polyvinyl alcohol [Duksan, Korea] instead of hydroxypropyl cellulose to prepare a photocatalyst coating sol and thin film.

<Example 4>

Preparation of Photocatalyst Device

An ultraviolet lamp [Sankyo, Japan] was installed inside a quartz tube having a 1000 mm, an inner diameter of 25 mm, and an outer diameter of 28 mm on which the photocatalyst thin film prepared in Example 1 was formed, and left and right of the quartz tube provided with the lamp [Sankyo, Japan]. The photocatalyst device was manufactured by installing the socket which can supply electric current.

Example 5

Manufacture of water treatment device

As shown in Figure 1, the upper opening of the "c" shaped support having a width of 250cm, vertical 950cm, height 950cm symmetrically installed to the left / right and then the top plate 300cm horizontal 1000cm It was provided with a connection with the support.

Then, a plurality of holes were symmetrically provided so that the photocatalyst device prepared in Example 4 was inserted between the respective supports, and then the photocatalyst device prepared in Example 4 was inserted and fixed in the holes.

<Example 6>

As shown in FIG. 3, four water treatment apparatuses prepared in Example 21 were installed in a reactor having a width, length, and height of 1600 cm × 1000 cm × 1000 cm, and partition walls were formed between the water treatment apparatuses.

Then, the raw water was supplied to one side of the reactor, the treated water was discharged to the other side, and a current was supplied to the water treatment terminal box to supply a current to the photocatalytic device constituting the water treatment device to perform photocatalytic oxidation.

The physical properties of the raw water and the treated water were measured.

The results are shown in Table 1.

enemy Number of treatments Turbidity (NTU) 2.5 1.1 Suspended solids [ppm] 65.5 9.0 Evaporation residue [ppm] 181 115 microbe positivity voice General bacteria [MPN / 100ml] 40 0 Total Organic Carbon [ppm] 6.8 0.4

Comparative Example 1

After mixing 30 g of titanium isopropoxide and 50 g of isopropyl alcohol, 0.1 g of nitric acid was added dropwise to react.

After completion of the reaction, 3 g of Degussa P-25 [Degussa, Germany] was added and then treated with an ultrasonic device Tip-sonicator for 1 hour to prepare a photocatalyst coating sol.

0.05 g of BYK-200 was added as a surfactant to the photocatalyst coating sol prepared according to Comparative Example 1, and then coated in a quartz tube having a length of 1000 mm, an inner diameter of 25 mm, and an outer diameter of 28 mm.

Then, the coated quartz tube was dried at about 200 ° C. for 30 minutes and then heat treated at 450 ° C. for 2 hours to form a photocatalyst thin film on the surface of the quartz tube having a length of 1000 mm, an inner diameter of 25 mm, and an outer diameter of 28 mm.

<Experiment>

The hardness of the photocatalyst thin films prepared by Examples 1 to 3 and the photocatalyst thin films prepared by Comparative Examples were measured according to a conventional pencil hardness measurement method.

The results are shown in Table 2.

Example 1 Example 2 Example 3 Comparative Example Hardness 7H 7H 7H 3H

As described above, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. Therefore, the above-described embodiments are to be understood as illustrative in all respects and not as restrictive. The scope of the present invention should be construed that all changes or modifications derived from the meaning and scope of the appended claims and their equivalents, rather than the detailed description, are included in the scope of the present invention.

The present invention is to prepare a photocatalyst coating sol using a titanium-based inorganic binder as described above, using a photocatalyst powder having photoactivity to the photocatalyst coating sol as a seed, using a polymer organic compound as an additive to the surface of the substrate By coating, drying, and heat-treating to thin a film, a photocatalyst device having high photocatalytic activity and not easily peeled off from the surface of the substrate can be prepared, and the photocatalyst coating sol is present in a waste water by manufacturing a water treatment device using a photocatalyst device having a thin film. It sterilizes microorganisms such as bacteria and fungi, and can oxidatively decompose toxic and hardly decomposable organic compounds such as pesticides and trihalomethane, and it is installed in waterways or photocatalysts when applied to water and sewage treatment facilities. Install an oxidation system to sterilize bacteria and microbes It can be used as an advanced oxidation treatment device that can oxidatively decompose toxic and hardly decomposable organic compounds such as pesticides and trihalomethanes, and sterilization and high oxidation can be applied to various wastewaters such as drinking water, industrial wastewater and leachate. It is possible.

In addition, the water treatment device is applied to rivers and lakes, etc., which has the effect of solving pollution by algae such as green algae and red tide generated in the rivers and lakes.

Claims (15)

0.1 to 10% by weight of photocatalyst powder, 1 to 50% by weight of titanium-based inorganic binder, 5 to 80% by weight of organic solvent, 1 to 30% by weight of high molecular organic compound, and 0.01 to 5% by weight of inorganic acid per sol solution for total photocatalyst coating Sol for photocatalyst coating. The method of claim 1, Sol for photocatalyst coating, characterized in that it further comprises 1 to 30% by weight of a chelating agent. The method according to claim 1 or 2, Sol for photocatalyst coating, characterized in that it further comprises 0.001 to 5% by weight surfactant. The method of claim 1, The photocatalyst is TiO ₂ , ZnO ₂ , ZnO, CaTiO, WO ₃ , SnO ₂ , MoO ₃ , Fe ₂ O ₃ , InP, GaAs, BaTiO ₃ , KNbO ₃ , Fe ₂ O ₃ , Ta ₂ O ₅ or Degussa P- Sol for photocatalyst coating, characterized in that selected from 25. The method of claim 1, The photocatalyst coating sol, characterized in that the titanium-based inorganic binder is a titanium alkoxide-based compound. The method of claim 1, The sol for photocatalyst coating, characterized in that the high molecular organic compound is hydroxypropyl cellulose, polyethylene glycol, polyvinyl alcohol or a mixture thereof. The method of claim 1, The photocatalyst coating sol, wherein the organic solvent is selected from ethyl alcohol, methyl alcohol, butyl alcohol, secbutyl alcohol, propyl alcohol, isopropyl alcohol or isopropanol. Iii) 1 to 50% by weight of the titanium-based inorganic binder and 0.1 to 30% by weight of the organic solvent are mixed per total photocatalyst coating sol solution, and 0.01 to 5% by weight of the inorganic acid is added to the mixture, followed by stirring for 0.1 to 10 hours. Reacting, Ii) mixing 1 to 30% by weight of the polymer organic compound and 5 to 50% by weight of the organic solvent, Iii) adding the mixture prepared in step ii) to the product prepared in step iv) and reacting with stirring for 0.5 to 10 hours, Iii) adding 0.1 to 10% by weight of the photocatalyst powder to the product of step iii) and then dispersing the photocatalyst powder by sonicating for 0.1 to 10 hours in an ultrasonic apparatus. The method of claim 8, Method for producing a photocatalyst coating sol, characterized in that to add 1 to 30% by weight of the chelating agent to step iii). The method according to claim 8 or 9, Method for producing a photocatalyst coating sol, characterized in that to add 0.001 to 5% by weight of surfactant to step iii). A substrate thinned by coating the photocatalyst coating sol according to any one of claims 1 to 7. The photocatalyst coating sol according to claim 1 is coated on the substrate by printing, spraying, or immersion and then dried at 50 to 450 ° C. for 0.1 to 50 hours, and the dried substrate at 120 to 650 ° C. Method for producing a photocatalyst thin film comprising the heat treatment for 0.1 to 50 hours. A quartz tube 14 having an empty inside and having a photocatalyst thin film formed by coating a photocatalyst coating sol according to any one of claims 1 to 7 on an outer surface thereof, which is provided inside the hollow quartz tube 14. And a lamp (10) installed to be connected to the lamp (10) to supply light to the lamp (10) to supply current to the lamp (10). The photocatalyst thin film 12 is formed by coating the photocatalyst coating sol according to claims 1 to 7 on the outer surface of the transparent cylindrical quartz tube 14 having an empty inside, and irradiating light to the photocatalyst thin film 12. At least one photocatalyst 6 and a photocatalyst 6 including a socket 10 for supplying a current to the lamp 10, the lamp 10 being provided inside the quartz tube 14. 6 and 6, the upper and lower ends of the socket 4 are inserted into and connected to one side of the upper end of the support 4 to fix the photocatalytic device 6, and the socket 8 is provided at the left and right ends of the socket 6, respectively. (28), a water treatment device comprising a terminal box (26) connected to and installed in the socket (8) of the photocatalyst device (6) to supply current, and a power supply member (16) to supply current to the terminal box. Inlet 20 is provided on one side of a predetermined reaction tank 32, the sewage is installed vertically with respect to the longitudinal direction of the reaction tank 32, the sewage flows from the top to the bottom or from the bottom to the top can be sequentially At least one or more partitions 30, between the partitions 30, at least one water treatment device 2 according to claim 14 for removing contaminants present in the sewage, and the respective water treatment devices 2. Is connected to the terminal box 26 to supply current, and is provided at one side of the power supply member 16 and the reaction tank 32 connected to the switchboard 24 to supply current. A water treatment system passing through the water treatment device 2 along the 30 and comprising a discharge port 22 through which the treated water is discharged.