KR20220067068A - Catalytic composite for catalytic ozone oxidation process and preparation method thereof - Google Patents

Abstract

The present invention relates to a catalytic composite for a catalytic ozone oxidation process and a preparation method thereof, and more particularly, to a catalytic composite for a catalytic ozone oxidation process which comprises: a porous ceramic membrane; and a catalyst formed on a pore surface of the porous ceramic membrane and supported with vanadium oxide (V_2O_5) on a titanium dioxide (TiO_2) carrier and decomposes ozone in water to generate hydroxyl radicals.

Description

Catalytic composite for catalytic ozone oxidation process and preparation method thereof

The present invention relates to a catalyst for a catalytic ozone oxidation process and a method for preparing the same.

Water is a basic element essential for human life, and as industry develops, urbanization progresses, and living standards improve, water pollution is becoming more serious. In order to solve this problem, various purification techniques have been developed to purify fresh water such as river water for drinking water or to purify wastewater or sewage water. Examples of this include a physical method of supplying compressed air to wastewater to constrict inclusions in air bubbles, a chemical method of coagulation and purification by injecting chemicals or reactive gases, a biological method of decomposing organic pollutants using microorganisms, chlorine Oxidation methods have been developed to treat pollutants by injecting substances with strong oxidizing power, such as morning, and have been used in combination.

On the other hand, general water treatment includes physical treatment (screening, sedimentation, coagulation, sedimentation separation, flotation separation, adsorption, etc.), chemical treatment (neutralization, aeration, oxidation, reduction, ion exchange, etc.), biological treatment (sprinkling filter bed method, activated sludge method) , anaerobic digestion method, aerobic digestion method, etc.) However, since it is difficult to treat recalcitrant organic matter only with these facilities, physicochemical treatment methods include activated carbon adsorption, Fenton oxidation method (H ₂ O ₂ ), ozone treatment (O ₃ ), photocatalyst and UV radiation, and biological treatment methods with highly active microorganisms Biological treatment using , two-stage aeration method, batch activated sludge method, anaerobic filter bed, etc. have been proposed.

In addition, in recent years, an oxidation process using ozone has been highlighted, and the oxidizing power of ozone is used to effectively remove organic matter from sewage and wastewater to reduce BOD concentration and to decolorize and deodorize. This ozone treatment is an advanced treatment system that converts difficult-to-decompose organic matter into BOD and COD substances that can be decomposed by microorganisms, but in the process using ozone as an oxidizer and disinfectant, decomposition of various types of wastewater and difficult-to-decompose organic matter according to the advancement of industry And it is difficult to convert to a low molecular weight material. In addition, although ozone has a superior oxidizing power (potential difference of 207 V) than conventional oxidizing agents, it is known that the reaction with most organic materials is slow or does not react at all with specific organic materials and selectively reacts.

Therefore, studies on the Advanced Oxidation Process (AOP) using ozone are being actively conducted to compensate for these drawbacks of ozone. In particular, the advanced oxidation process using ozone generates OH radicals (·OH, potential difference: 308 V) with stronger oxidizing power than the oxidizing agent used in the existing oxidation process in the reactor to convert organic compounds contained in water into CO ₂ and H ₂ It is a technology that decomposes into compounds such as O and HCl, and is widely used in water treatment in recent years. OH radicals have stronger oxidizing power than ozone and react very quickly with organic substances, and can react with various organic substances because there is no selectivity for the bonding state of molecules.

The advanced oxidation process using this principle includes the ozone/hydrogen peroxide process, which increases the generation efficiency of OH radicals by adding hydrogen peroxide, and ozone/high-grade ozone using ozone that is converted into OH radicals by self-decomposition under high pH conditions. The pH process and ozone/UV photolysis method that maximizes ozone decomposition efficiency by irradiating ultraviolet light are representative. However, ozone and UV photolysis methods are more efficient and easier to maintain than ozone and hydrogen peroxide methods because ozone absorbs UV rays and photodecomposes them to generate OH radicals in water through ozone decomposition mechanism. Due to the significant reduction in UV intensity, economical and practical issues remain in field application. In addition, since hydrogen peroxide and other additional devices are required, even if ozone is continuously supplied, initial installation and maintenance costs may increase.

On the other hand, as an Advanced Oxidation Process (AOP), Korean Patent No. 10-0720035 discloses a water treatment apparatus using a photocatalyst and a treatment method thereof. This photocatalyst/UV method oxidizes and decomposes organic matter by irradiating UV on the photocatalyst to generate OH radicals on the surface of the photocatalyst. There is a problem with the recovery of the powder and the disadvantages of the above-mentioned UV.

In addition, although a method of activating ozone using metal ions in water as a catalyst has been disclosed, this method is effective in removing organic matter because the transition metal present in water promotes the generation of OH radicals, but such a homogeneous catalyst The method used has a problem in that an additional process for recovery of the catalyst is required after the reaction.

Recently, to overcome this problem, in order to improve ozone decomposition efficiency by using a semi-permanent catalyst, heterogeneous catalysts in which various metals and metal compounds are physically and chemically supported on a support such as activated carbon are used in advanced oxidation processes. This method has been widely used in the actual water treatment process because it is easy to recover after use and can be reused through a regeneration process.

However, in the case of such a heterogeneous catalyst, there are problems to be overcome, such as the activity and durability of the catalyst in water, and more research is needed.

Accordingly, the present inventors are a catalyst in which vanadium oxide (V ₂ O ₅ ) is supported on a porous ceramic membrane using titanium dioxide (TiO ₂ ) as a carrier, and the content of vanadium oxide supported on the titanium dioxide (TiO ₂ ) carrier is controlled. By doing so, a catalyst capable of improving ozone decomposition and generation of OH radicals in water was developed and the present invention was completed.

Republic of Korea Patent Registration No. 10-0720035

In one aspect, the purpose

To provide a catalyst for a catalytic ozone oxidation process.

In addition, the purpose in another aspect is

An object of the present invention is to provide a method for preparing a catalyst for a catalytic ozone oxidation process.

In addition, the purpose in another aspect is

An object of the present invention is to provide a method for removing organic pollutants in water using the catalyst for the catalytic ozone oxidation process.

In order to achieve the above object,

In one aspect,

porous ceramic membrane; and

It is formed on the pore surface of the porous ceramic membrane, and a catalyst in which vanadium oxide (V ₂ O ₅ ) is supported on a titanium dioxide (TiO ₂ ) carrier; includes;

A catalyst body for a catalytic ozone oxidation process is provided that decomposes ozone in water to produce hydroxyl radicals.

In this case, the catalyst may contain 3 mol% to 8 mol% of vanadium oxide (V ₂ O ₅ ) relative to the titanium dioxide (TiO ₂ ).

The average diameter of the pores of the porous ceramic membrane may be 10 nm to 10 μm.

The porous ceramic film is an oxide ceramic including alumina (Al ₂ O ₃ ), diatomite, aluminum nitride (AlN), silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), zirconium carbide (ZrC), tungsten carbide It may be made of at least one selected from (WC), cordierite (Cordierite) and mullite (Mullite).

The catalyst may be nanoparticles having an average diameter of 10 nm to 1000 nm.

Also, in another aspect,

Coating a gel solution containing titanium dioxide (TiO ₂ ) and vanadium oxide (V ₂ O ₅ ) on the surface of the pores of the porous ceramic membrane; and

There is provided a method for preparing a catalyst for a catalytic ozone oxidation process, comprising: calcining the ceramic film coated with the gel solution; and preparing the catalyst for generating hydroxyl radicals by decomposing ozone in water.

In this case, the catalyst may contain 3 mol% to 8 mol% of the vanadium oxide (V ₂ O ₅ ) relative to titanium dioxide (TiO ₂ ).

The coating may be performed by applying a predetermined pressure to allow the gel solution to pass through the porous ceramic membrane.

The firing may be performed at a temperature of 450°C to 650°C.

Further, in another aspect,

A method for treating organic matter in water is provided, comprising: supplying raw water containing organic matter and oxidized water containing ozone to the catalyst for the catalytic ozone oxidation process to decompose the organic matter.

The catalyst for a catalytic ozone oxidation process provided in one aspect may further improve ozone decomposition and generation of OH radicals during an Advanced Oxidation Process (AOP) using ozone. Accordingly, by performing an advanced oxidation process using the catalyst, organic pollutants contained in water can be effectively decomposed.

In particular, the catalyst for the catalytic ozone oxidation process provided in one aspect has the advantage that the catalyst is supported on a porous ceramic membrane, so it is easy to recover after use and can be reused through a regeneration process, and the ceramic membrane as a catalyst support By using it, there is an advantage in that the durability of the catalyst is excellent by improving the thermal and mechanical stability of the catalyst.

In addition, in the method for preparing a catalyst for ozone oxidation process provided in another aspect, a porous ceramic membrane is coated with a gel solution containing titanium dioxide (TiO ₂ ) and vanadium oxide (V ₂ O ₅ ) and then fired by firing the porous ceramic A catalyst in the form of particles is formed on a membrane. Compared to the method of coating a catalyst in powder form on a ceramic membrane, the bonding strength between the catalyst and the ceramic membrane is high, so it has the advantage of being able to prepare a catalyst body with excellent stability of catalytic activity. .

1 is a schematic diagram showing a part of a catalyst for a catalytic ozone oxidation process provided in one aspect and a process in which ozone is decomposed, OH is generated, and micropollutants in water are decomposed using the same;
2 is a schematic diagram showing an example of a coating step in the method for preparing a catalyst for a catalytic ozone oxidation process provided in another aspect;
3 is a schematic diagram showing a method for treating organic pollutants in water according to another aspect;
4 is a result of analyzing a catalyst for a catalytic ozone oxidation process according to an aspect using a scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX);
5 is a graph comparing the signal intensity obtained from Electron Spin Resonance Spectroscopy (ESR) in the case of using the catalyst prepared in Examples and Comparative Examples and in the case of not using the catalyst. ,
6 is a graph comparing the amount of OH radical generation calculated from the ESR analysis of FIG. 5;
7 is a graph showing the removal rate for various organic pollutants in raw water measured using the catalyst for the catalytic ozone oxidation process prepared according to the example;
8 is a graph comparing removal rates of organic contaminants in raw water when using the catalyst body of Example in which the catalyst is formed on a porous ceramic membrane, when the porous ceramic membrane is not used, and when the catalyst is not used.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. In addition, the following examples are provided in order to more completely explain the present invention to those of ordinary skill in the art. Accordingly, the shapes and sizes of elements in the drawings may be exaggerated for clearer description. In addition, "including" a certain element throughout the specification means that other elements may be further included, rather than excluding other elements, unless specifically stated otherwise.

in one aspect

porous ceramic membrane; and

It is formed on the pore surface of the porous ceramic membrane, and a catalyst in which vanadium oxide (V ₂ O ₅ ) is supported on a titanium dioxide (TiO ₂ ) carrier; includes;

A catalyst body for a catalytic ozone oxidation process is provided that decomposes ozone in water to produce hydroxyl radicals.

The catalyst for the catalytic ozone oxidation process decomposes ozone and generates OH radicals to decompose organic compounds contained in water into compounds such as CO ₂ and H ₂ O and HCl. In Advanced Oxidation Process: AOP), it is a catalyst for activating ozone and consequently promoting generation of OH radicals.

Hereinafter, a catalyst for a catalytic ozone oxidation process provided in one aspect will be described in detail with reference to the drawings.

The catalyst body includes a porous ceramic membrane.

The average diameter of the pores of the porous ceramic membrane may be 10 nm to 10 μm.

If the size of the pores is less than 10 nm, the resistance to the porous ceramic membrane may be large and the processing flow rate may be lowered. can be

In addition, the porosity of the porous ceramic membrane may be 20 to 60%.

This is to increase durability and efficiency of the catalytic ozone oxidation process, and the catalyst body may increase durability through the porous ceramic membrane.

If the porosity is less than 20%, the permeation rate becomes small and the permeate flow rate is lowered, which may cause a problem that the catalytic ozone oxidation process efficiency is lowered. If the porosity exceeds 60%, the durability of the ceramic membrane (mechanical strength) may be lowered.

In addition, the porous ceramic membrane is an oxide ceramic containing alumina (Al ₂ O ₃ ), diatomite, aluminum nitride (AlN), silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), zirconium carbide (ZrC), It may be made of at least one selected from among tungsten carbide (WC), cordierite, and mullite, but is not limited thereto, and may include other materials having high chemical stability and excellent durability.

The shape of the porous ceramic membrane may be any one of a hollow fiber membrane type, a tubular membrane type, and a flat membrane type, but is not limited thereto, and various types that can be used for water treatment may be applied.

In addition, the porous ceramic membrane can stably support the catalyst as a support for supporting the catalyst, and can provide a sufficient space for ozone gas to be accommodated in the catalytic ozone oxidation process.

In addition, filtration, separation, and catalytic reaction may be performed by making the catalyst body have a three-dimensional three-dimensional network structure having porosity.

Accordingly, the catalyst body can promote the generation of OH radicals from ozone by forming the catalyst on the porous ceramic membrane, and can effectively remove organic pollutants in water by the OH radicals.

In this case, the catalyst formed in the porous ceramic membrane may be in the form of titanium dioxide (TiO ₂ ) supported on a support of vanadium oxide (V ₂ O ₅ ).

The catalyst may be preferably formed on the surface of the pores of the porous ceramic membrane, through which the contact surface with ozone flowing into the pores of the porous ceramic membrane is widened, thereby generating OH by ozone and removing organic pollutants thereby Efficiency can be further improved.

In addition, the catalyst is in the form of nanoparticles formed by being coated on the porous ceramic membrane in the form of a gel and then calcined, and is strongly bound to the porous ceramic membrane.

In this case, the average diameter of the nanoparticles may be 10 nm to 1000 nm, but is not limited thereto, and may vary depending on the pore size of the ceramic film.

The catalyst is a titanium dioxide (TiO ₂ ) carrier in which vanadium oxide (V ₂ O ₅ ) is supported, and the titanium dioxide (TiO ₂ ) carrier interacts with organic contaminants to adsorb the organic contaminants, OH radicals may be generated from ozone, and the vanadium oxide (V ₂ O ₅ ) may further promote generation of OH radicals from ozone.

Accordingly, the catalyst provided in one aspect can adsorb and decompose organic pollutants into OH radicals, and thus can be particularly effective in removing trace amounts of organic pollutants such as pharmaceuticals contained in water.

Accordingly, the catalyst can promote the generation of OH radicals in ozone and at the same time improve the reaction amount with ozone and organic pollutants, thereby further improving the removal efficiency of organic pollutants by the catalytic ozone oxidation process.

In this case, the generation of OH radicals by the catalyst may vary depending on the content ratio of titanium dioxide (TiO ₂ ) and vanadium oxide (V ₂ O ₅ ).

Accordingly, in order to promote the generation of OH radicals, the catalyst preferably contains 3 mol% to 8 mol% of vanadium oxide (V ₂ O ₅ ) relative to the titanium dioxide (TiO ₂ ), more preferably 3 mol% % to 5 mol%, if the vanadium oxide (V ₂ O ₅ ) is included in less than 3 mol% or in excess of 8 mol%, OH radical by vanadium oxide (V ₂ O ₅ ) The production improvement effect may be insignificant, or the amount of OH radical production may be lowered.

On the other hand, in another aspect,

Coating a gel solution containing titanium dioxide (TiO ₂ ) and vanadium oxide (V ₂ O ₅ ) on the surface of the pores of the porous ceramic membrane; and

There is provided a method for preparing a catalyst for catalytic ozone oxidation, comprising the step of calcining the ceramic support coated with the gel solution, and preparing the catalyst for generating hydroxyl (OH) radicals by decomposing ozone in water .

In the method for preparing a catalyst for catalytic ozone oxidation provided in another aspect, a catalyst in the form of nanoparticles is formed on the surface of the pores of the porous ceramic membrane with a strong binding force by coating the catalyst in a gel state on a porous ceramic membrane and then sintering. Therefore, it is possible to prepare a catalyst having excellent activity stability.

In addition, the prepared catalyst can improve the generation of OH radicals by ozone decomposition, and can increase the reaction amount of OH radicals and organic pollutants by adsorbing free pollutants, so that organic contamination by the catalytic ozone oxidation process It is possible to further improve the material removal efficiency.

Hereinafter, a method for preparing a catalyst for catalytic ozone oxidation provided in another aspect will be described in detail for each configuration.

First, the method for preparing a catalyst for catalytic ozone oxidation provided in another aspect includes coating a gel solution containing titanium dioxide (TiO ₂ ) and vanadium oxide (V ₂ O ₅ ) on the surface of the pores of a porous ceramic membrane. may include

The above step is a step for forming a catalyst in a porous ceramic membrane that is a catalyst support.

In this case, the generation of OH radicals by the catalyst may vary depending on the content ratio of titanium dioxide (TiO ₂ ) and vanadium oxide (V ₂ O ₅ ).

Accordingly, in order to promote the generation of OH radicals, the catalyst preferably contains 3 mol% to 8 mol% of vanadium oxide (V ₂ O ₅ ) relative to the titanium dioxide (TiO ₂ ), more preferably 3 mol% % to 5 mol%, if the vanadium oxide (V ₂ O ₅ ) is included in less than 3 mol% or in excess of 8 mol%, OH radical by vanadium oxide (V ₂ O ₅ ) The production improvement effect may be insignificant, or the amount of OH radical production may be lowered.

In the method for preparing a catalyst for catalytic ozone oxidation provided in another aspect, a catalyst body including a catalyst strongly bound to a porous ceramic membrane can be prepared by coating a gel-type catalyst on a ceramic membrane and then calcining.

On the other hand, when the catalyst in powder form is coated on the ceramic membrane, the bonding force between the catalyst and the ceramic membrane is weak, so there may be problems in that the catalyst is not properly attached and the stability of the catalyst activity is low.

At this time, in order for the gel solution to be coated inside the porous ceramic membrane, preferably on the surface of the pores of the porous ceramic membrane, the coating may be performed by applying a predetermined pressure to allow the gel solution to pass through the porous ceramic support. have.

FIG. 2 is a schematic view showing an embodiment of the coating. As shown in FIG. 2, after the porous ceramic membrane is formed in the form of a hollow fiber membrane having a hollow part extending from one end to the other end, one end of the ceramic membrane is sealed. In this state, a predetermined pressure is applied using a syringe pump, etc., so that the gel solution is injected into the hollow part of the ceramic membrane through the other end of the ceramic membrane, and through this, the gel solution flows from the hollow part to the surface of the ceramic membrane. The gel solution may be coated on the pore surface of the ceramic membrane.

Next, the method for preparing a catalyst for catalytic ozone oxidation provided in another aspect may include firing the ceramic membrane coated with the gel solution.

The above step is a step of forming nanoparticles by calcining the gel solution. Through the above step, a catalyst in the form of nanoparticles may be formed on the surface of the pores of the porous ceramic membrane.

The calcination may be performed at a temperature of 450 °C to 650 °C, more preferably at a temperature of 500 °C to 600 °C.

On the other hand, in another aspect,

There is provided a method for treating organic pollutants in water, comprising: supplying raw water containing organic pollutants and oxidized water containing ozone to the catalyst for catalytic ozone oxidation to decompose the organic pollutants.

In this case, the organic pollutants are aromatic benzene ring compounds (chlorobenzene, nitrobenzene, decahydronaphthalene, benzene, cresol, xylene, tetrahydronaphthalene, Organic pollutants such as tetrahydrofuran, toluene, phenol, ethylphenol, ethylbenzene, pyridine, etc.) and halogenated organic compounds (TCE: trichloroethylene, PCE: perchlorethylene, PCP: pentachlorophenol, tetrachloroethylene, etc.) In particular, it may include residual antibiotics and medicinal substances contained in trace amounts in water, such as carbamazepine, bezafilbrate, sulfamethoxazole, and diclofenac. .

3 is a schematic diagram showing a method for treating organic pollutants in water according to another aspect. As shown in FIG. 3, raw water containing organic pollutants and oxidation water containing ozone are used as the catalyst for catalytic ozone oxidation. By supplying it, organic pollutants contained in raw water can be decomposed.

In this case, the raw water containing the organic pollutants and the oxidation water may be simultaneously introduced into the catalyst body using a pump, and the organic pollutants contained in the raw water introduced into the catalyst body may be adsorbed to the catalyst body, and the The organic pollutants adsorbed to the catalyst may be decomposed by OH radicals formed by decomposition of ozone contained in the oxidation water.

Hereinafter, the present invention will be described in detail through Examples and Experimental Examples.

However, the following examples and experimental examples are only to illustrate the present invention, the content of the present invention is not limited by the following examples.

<Example 1>

Step 1: A gel solution containing titanium dioxide (TiO ₂ ) and vanadium oxide (V ₂ O ₅ ) was prepared by the following method.

First, a solution was prepared so that titanium butoxide was 0.01 mol in 3 ml of acetic acid and 25 ml of butanol, and 0.001 mol of vanadium oxide in 40 ml of hydrogen peroxide Each was prepared so as to be a solution. The two solutions were mixed at 150 rpm at 80° C. for 2 hours or more to prepare a gel containing 1 mol% of vanadium oxide (V ₂ O ₅ ) compared to titanium dioxide (TiO ₂ ).

Step 2: Apply the gel solution to a porous alumina membrane in the form of a hollow fiber membrane having pores of 303±18 nm (effective area inside the membrane: 2.20 cm, internal volume: 0.06 mL) as shown in FIG. It was coated using an -out coating device.

At this time, the in-out coating device has one end of the porous alumina membrane sealed and the other end connected with a syringe, and after filling the syringe with the gel solution, join the syringe pump so that the gel solution enters the alumina membrane. It was designed so that the gel solution filled the voids while flowing out from the inside of the alumina membrane.

Step 3: Firing the alumina film coated with the gel solution at 550° C. to form nanoparticles with a size of 50 nm to 150 nm on the pore surface of the alumina film, titanium dioxide (TiO ₂ ) vs. vanadium oxide (V ₂ O ₅ ) 1 mol % of the catalyst to form a catalyst body formed on the pore surface of the porous alumina membrane.

<Example 2>

In step 1 of Example 1, the same method as in Example 1 was performed except that a gel containing 2 mol% of titanium dioxide (TiO ₂ ) versus vanadium oxide (V ₂ O ₅ ) was prepared. Thus, a catalyst containing 2 mol% of vanadium oxide (V ₂ O ₅ ) compared to titanium dioxide (TiO ₂ ) was formed on the surface of the pores of the porous alumina membrane to form a catalyst body.

<Example 3>

In step 1 of Example 1, the same method as in Example 1 was performed except that a gel containing 4 mol% of titanium dioxide (TiO ₂ ) versus vanadium oxide (V ₂ O ₅ ) was prepared. Thus, a catalyst containing 4 mol% of vanadium oxide (V ₂ O ₅ ) compared to titanium dioxide (TiO ₂ ) was formed on the surface of the pores of the porous alumina membrane to form a catalyst body.

<Example 4>

In step 1 of Example 1, the same method as in Example 1 was performed except that a gel containing 10 mol% of titanium dioxide (TiO ₂ ) versus vanadium oxide (V ₂ O ₅ ) was prepared. Thus, a catalyst containing 10 mol% of vanadium oxide (V ₂ O ₅ ) compared to titanium dioxide (TiO ₂ ) was formed on the surface of the pores of the porous alumina membrane to form a catalyst body.

<Example 5>

In step 1 of Example 1, the same method as in Example 1 was performed except that a gel containing 20 mol% of titanium dioxide (TiO ₂ ) versus vanadium oxide (V ₂ O ₅ ) was prepared. Thus, a catalyst containing 20 mol% of vanadium oxide (V ₂ O ₅ ) compared to titanium dioxide (TiO ₂ ) was formed on the surface of the pores of the porous alumina membrane to form a catalyst body.

<Comparative Example 1>

In the same manner as in Example 1, except that step 1 of Example 1 was performed as follows, a catalyst body in which a titanium dioxide (TiO ₂ ) catalyst was formed on the pore surface of the porous alumina membrane was formed.

Step 1: Prepare a solution so that titanium butoxide is 0.01 mol in 3 ml of acetic acid and 25 ml of butanol, and mix at 150 rpm at 80° C. for 2 hours or more to obtain titanium dioxide (TiO ₂ ) ) containing a gel (Gel) was prepared.

<Comparative Example 2>

A porous alumina membrane in the form of a hollow fiber membrane (effective area inside the membrane: 2.20 cm, internal volume: 0.06 mL) was prepared.

<Comparative example 3>

In the same manner as in Step 1 of Example 1, a catalyst in which vanadium oxide (V ₂ O ₅ ) is supported on a titanium dioxide (TiO ₂ ) carrier was prepared.

At this time, the titanium dioxide (TiO ₂ ) compared to vanadium oxide (V ₂ O ₅ ) was prepared to contain 4 mol%.

<Experimental Example 1> Analysis of the shape of the catalyst body

Example using a scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX) to confirm the shape and element distribution of the inner surface and cross-section of the porous ceramic membrane of the catalyst for the catalytic ozone oxidation process according to an aspect Surface analysis and element distribution mapping were performed on the catalyst of 3, and the results are shown in FIG. 4 .

As shown in FIG. 4 , in the catalyst body of Example 3, it can be confirmed that titanium (T) and vananium (V) are uniformly formed on both the inner surface and cross section of the porous alumina hollow fiber membrane, and through this, titanium dioxide (TiO ₂ ) It can be seen that the catalyst on which vanadium oxide (V ₂ O ₅ ) was supported on the carrier was uniformly formed on the porous alumina hollow fiber membrane.

<Experimental Example 2> Measurement of OH radical generation amount

Electron spin resonance spectroscopy (electron spin resonance spectroscopy) to confirm the amount of OH radicals generated by ozone decomposition when the catalysts prepared in Examples 1 to 5 and Comparative Example 1 were used and when the catalyst was not used , ESR) was used to measure the amount of OH radical generation under the device setting conditions of Table 1, and the measurement conditions of Tables 2 and 3, and the results are shown in FIGS. 5 and 6 .

setting items set value center field 336mV Power 30mV scan time 2min Width+/- 10 mT Mod width 0.5 mT Amplitude 500 Time constant 0.03

initial concentration final concentration MPs 10mg/L 2mg/L ozone - 4mg/L catalyst 10mg/L 1mg/L

DMPO
(100 mM) MPs
(mL) Catalyst (mL) Ozone
(mL) HCl
(mL) Total volume (mL) Comparative Example 2 0.4 0.4 0 0.8 0.2 1.8 Examples 1 to 5, Comparative Example 1 0.4 0.4 0.2 0.8 0.2 2.0

MPs: Micropollutants

5 is a signal strength graph from ESR analysis, and FIG. 6 is a graph showing the difference between the minimum and maximum values in the 335 to 340 mT magnetic field range in the signal strength graph of FIG. 5, wherein the minimum and the 335 to 340 mT magnetic field range It can be seen that the greater the difference between the maximum values, the greater the amount of OH radicals generated.

As shown in FIGS. 5 and 6 , when using the catalyst of Example 3 in which vanadium oxide (V ₂ O ₅ ) was supported at 4 mol% on a titanium dioxide (TiO ₂ ) support, the largest difference in signal value was obtained. It can be seen that, through this, when the catalyst of Example 3 is used, it can be seen that the most OH radicals are generated.

<Experimental Example 3> Measurement of removal rate of trace organic pollutants (1)

In order to measure the removal rate of organic pollutants when the catalyst prepared in Example 3 is used, raw water containing fine organic pollutants and oxidized water containing ozone were simultaneously prepared in Example 3 in the same manner as in FIG. 3 . The content of organic contaminants in the passed treated water was measured by putting it in one catalyst body and allowing it to pass through, thereby measuring the removal rate of organic contaminants, and the results are shown in FIG. 7 .

At this time, raw water was made to contain carbamazepine, bezafilbrate, sulfamethoxazole, and diclofenac as trace organic pollutants.

7, the catalyst of Example 3 was removed with a high removal rate of 80% or more with respect to carbamazepine, bezafilbrate, sulfamethoxazole, and diclofenac. It can be seen that, in particular, for Diclofenac, it can be seen that it is removed with a high removal rate of 98% or more.

Through this, it can be seen that the catalyst for the catalytic ozone oxidation process according to one aspect can remove organic pollutants in water very well, and in particular, carbamazepine, bezafilbrate, sulfa It can be seen that trace organic contaminants such as methoxazole and diclofenac can be removed with a remarkably excellent removal rate.

Trace organic pollutants Removal rate (%) Carbamazepine 89.29736 Bezafilbrate 66.71449 Sulfamethoxazole 85.29017 Diclofenac 99.46307

<Experimental Example 4> Measurement of removal rate of micro organic pollutants (2)

According to one aspect, when organic contaminants are removed by the method of Experimental Example 3 using the catalyst body of Example 3 in which a catalyst is formed on a porous ceramic membrane (Hydrid of FIG. When organic pollutants are removed by adding ozone after dispersing the catalyst of Comparative Example 3 in raw water containing pollutants (Suspended in FIG. 8) and without using a catalyst, in raw water containing organic pollutants The removal rate of organic pollutants in the case of removing organic pollutants by adding ozone (O ₃ in FIG. 8 ) was compared and measured, and the results are shown in FIG. 8 .

At this time, to measure the organic pollutant removal rate, humic acid, fulvic acid, carbamazepine, bezafilbrate, sulfamethoxazole, diclofenac, diethyl The total removal amount of hydroxylamine (Diethylhydroxylamine) and ethylhexyl phthalate (Di(2-ethylhexyl) phthalate) was measured.

As shown in FIG. 8 , it can be seen that the removal rate of organic contaminants is higher when the titanium dioxide (TiO ₂ ) carrier includes a catalyst in which vanadium oxide (V ₂ O ₅ ) is supported, compared to the case where the catalyst is not supported. Even if a catalyst is used, it can be seen that the removal rate of organic pollutants is significantly increased to 90% or more when a catalyst body in which a catalyst is formed on a porous ceramic membrane is used compared to the case where the catalyst is dispersed in raw water.

This is believed to be because, by forming the catalyst on the pore surface of the porous ceramic membrane, the contact between ozone and the catalyst becomes more favorable, thereby improving ozone decomposition and generation of OH radicals.

Claims (10)

porous ceramic membrane; and
It is formed on the pore surface of the porous ceramic membrane, and a catalyst in which vanadium oxide (V ₂ O ₅ ) is supported on a titanium dioxide (TiO ₂ ) carrier; includes;
A catalyst for a catalytic ozone oxidation process, which decomposes ozone in water to produce hydroxyl radicals.
According to claim 1,
The catalyst is the titanium dioxide (TiO ₂ ) compared to vanadium oxide (V ₂ O ₅ ) The catalyst body for a catalytic ozone oxidation process comprising 3 mol% to 8 mol%.
According to claim 1,
An average diameter of the pores of the porous ceramic membrane is 10 nm to 10 μm, a catalyst body for a catalytic ozone oxidation process.
According to claim 1,
The catalyst is nanoparticles having an average diameter of 10 nm to 1000 nm, a catalyst for a catalytic ozone oxidation process.
According to claim 1,
The ceramic film is an oxide ceramic containing alumina (Al ₂ O ₃ ), diatomite, aluminum nitride (AlN), silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), zirconium carbide (ZrC), tungsten carbide ( WC), cordierite (Cordierite) and mullite (Mullite) consisting of at least one selected from, a catalyst for a catalytic ozone oxidation process.
Coating a gel solution containing titanium dioxide (TiO ₂ ) and vanadium oxide (V ₂ O ₅ ) on the surface of the pores of the porous ceramic membrane; and
A method for producing a catalyst for a catalytic ozone oxidation process, comprising: calcining the ceramic membrane coated with the gel solution;
7. The method of claim 6,
The catalyst of the catalyst is titanium dioxide (TiO ₂ ) compared to vanadium oxide (V ₂ O ₅ ) 2 mol% to 6 mol% of the method for producing a catalyst for a catalytic ozone oxidation process.
7. The method of claim 6,
The coating step is performed by applying a predetermined pressure to allow the gel solution to pass through the porous ceramic membrane.
7. The method of claim 6,
The calcination is carried out at a temperature of 450 ° C to 650 ° C, ozone in water - a method for producing a catalyst for a catalytic process.
A method for treating organic matter in water, comprising: supplying raw water containing organic matter and oxidized water containing ozone to the catalyst for the catalytic ozone oxidation process of claim 1 to decompose the organic matter.

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