JPH11244708A - Photocatalyst member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photocatalyst member effectively utilizing exciting light and having high air permeability in the photocatalyst member for decomposing and removing a harmful substance such as a malodor or bacteria by the photooxidation decomposing action of a photocatalyst. SOLUTION: A photocatalyst member supporting a photocatalyst supported thereon and containing a corrugated photocatalyst member wherein a liner surface has an oblique angle with respect to the opening surfaces of cells or a corrugated light catalyst member as a part of a constitutional element utilizes exciting effect effectively though there is almost no difference in air permeability compared with a conventional photocatalyst member and is excellent in deodorizing capacity. Especially, a composite layer photocatalyst member wherein two or more corrugated photocatalyst members are laminated utilizes exciting light extremely effectively and the photocatalyst member still excellent in deodorizing capacity is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a photocatalyst member,
More specifically, by the photocatalytic action of a photoreactive semiconductor,
The present invention relates to a photocatalyst member which not only can decompose and remove harmful substances such as bad smells and bacteria, but also has an effective use of excitation light and a high degree of air permeability.

[0002]

2. Description of the Related Art Problems of conventional environmental pollution caused by industrially generated odors and harmful chemical substances in factories, and odors caused by wastes in service industries such as restaurants and hotels that discharge a large amount of waste. In addition, with the recent increase in amenity-oriented, the problem of indoor environmental pollution due to odors and harmful chemical substances in general living spaces, for example, indoors and cars, has been increasing, and the need for the removal of these harmful substances has been increasing. It is growing rapidly.

[0003] As a method of removing harmful substances such as odors and harmful chemical substances, porous substances such as activated carbon and zeolite,
A so-called adsorption removal by an adsorbent is common. However, the adsorbent only shows an adsorbing effect on most harmful substances, and when a certain amount of harmful substances is adsorbed, the removal performance is significantly reduced, or harmful substances once adsorbed depending on the ambient temperature and concentration of harmful substances. There is a problem that the substance is detached.

In order to solve such a problem, a method of decomposing and removing harmful substances using a catalyst has been devised.
Various materials having a capability of decomposing and removing harmful substances are known, and among them, a photocatalyst member represented by titanium oxide has recently received a great deal of attention. For example, Cundall et al.
J. Oil. Chem. Assoc. 1978, 61,
In 351, when titanium oxide is irradiated with ultraviolet light,
It is reported that alcohol is decomposed in a mixed system of water and alcohol. Further, JP-A-61-135669 reports that when a photocatalyst member such as zinc oxide is irradiated with ultraviolet light, a sulfur compound as a malodorous substance is decomposed. In the decomposition reaction by these photocatalyst members, the photocatalyst member is not consumed as the reaction proceeds, and its decomposition ability is semi-permanent as long as it is exposed to light. Such a photocatalytic reaction is an interfacial reaction, and the more efficiently the photocatalyst member contacts the decomposition target, the more efficiently it proceeds. Therefore, as the shape of the photocatalyst member,
It is preferable that the powder has a large specific surface area,
It is difficult to use the photocatalyst member as powder, and it is necessary to carry and fix the photocatalyst member on an appropriate support using some method.

[0005] For example, Japanese Patent Application Laid-Open No.
In order to increase the amount of a catalyst that receives light irradiation per unit volume, a method of supporting a photocatalyst on a honeycomb structure, as disclosed in Japanese Patent Application Laid-Open No. 22-45130 and Japanese Utility Model Application Laid-Open No. 2-45130, has been used.

[0006] These honeycomb-shaped photocatalyst members are characterized in that the problem of pressure loss is small and the amount of catalyst that receives light irradiation per unit volume is large, but light irradiation is performed almost in parallel to the catalyst surface. However, there has been a problem that the energy of the light applied to the catalyst surface is reduced, and the efficiency is deteriorated.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photocatalytic member for decomposing and removing harmful substances such as bad smells and bacteria by the photo-oxidative decomposition action of a photocatalyst. An object of the present invention is to provide a photocatalyst member which is used and has high air permeability.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention.

(1) A corrugated photocatalyst member carrying a photocatalyst, wherein the liner surface has an oblique angle with respect to the opening surface of the cell.

(2) A photocatalyst member which carries a photocatalyst and which includes, as a component, a corrugated photocatalyst member having a liner surface at an oblique angle with respect to the opening surface of the cell.

(3) In the above invention (1) or (2), the oblique angle of the corrugated photocatalyst member is 30 °.
A photocatalyst member characterized by being at an angle of up to 60 °.

(4) In the above invention (1), (2) or (3), the oblique angle (X), pitch (Y) and thickness (Z) of the corrugated photocatalyst member with respect to the opening surface of the cell. A photocatalyst member, wherein the relationship of the three is Y ≦ ZcosX.

(5) The photocatalyst member according to the invention (2), (3) or (4), wherein two or more corrugated members are laminated.

(6) The above inventions (2), (3) and (4)
Or (5) The photocatalyst member according to (5), wherein two corrugated photocatalyst members having the same shape are stacked upside down.

(7) The above inventions (1), (2),
(3) The photocatalyst member according to (4), (5) or (6), wherein at least a part of the corrugated photocatalyst member constituting the photocatalyst member is formed of a fibrous sheet supporting a photocatalyst.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention provides a corrugated photocatalyst member carrying a photocatalyst and having a liner surface at an oblique angle with respect to an opening surface of a cell. A photocatalyst member included as a part of an element. While utilizing the features of the conventional corrugated member that the surface area per unit volume is large and the pressure loss is extremely small, the light receiving surface can be further increased and the photocatalytic excitation light can be used effectively.

In the photocatalyst member of the present invention, it is preferable that the oblique angle of the corrugated photocatalyst member is 30 ° to 60 °. If the angle is less than 30 °, there is a problem that it is difficult to obtain sufficient air permeability because the cell wall of the corrugated liner hinders the flow of air. On the other hand, when the angle exceeds 60 °, the photocatalyst member needs to be thickened in order to effectively use the excitation light, which causes a problem that the excitation light is insufficient for the photocatalyst. Therefore, in order to achieve both air permeability and effective use of the excitation ultraviolet light, it is more preferable that the oblique angle of the liner with respect to the opening surface of the cell is around 45 °.

In the photocatalyst member of the present invention, the relationship between the oblique angle (X), pitch (Y) and thickness (Z) of the corrugated photocatalyst member with respect to the opening surface of the cell is Y ≦ ZcosX. It is more preferred that there be. If this condition is not satisfied, the excitation light leaks from the photocatalyst member, so that the effective use of the excitation light cannot be sufficiently achieved.

The photocatalyst member (2), (3) or (4) of the present invention is more preferably a photocatalyst member obtained by laminating two or more corrugated photocatalyst members.

Furthermore, (2), (3) and (4) of the present invention
Alternatively, the photocatalyst member (5) is more preferably a photocatalyst member formed by stacking two corrugated photocatalyst members of the same shape upside down.

The pitch in the present invention represents the distance between liners as shown in FIG. The term “thickness” in the present invention refers to the thickness of the corrugate as shown in FIG.

When the photocatalyst member of the present invention is composed of two or more corrugated photocatalyst members, the photocatalyst members may be overlapped with each other, or may be provided with a slight gap by using a spacer or the like. May be laminated.
By adopting a structure having such a gap, turbulence of air is generated between the two layers, the chance of contact between the decomposed substance and the photocatalyst is increased, and the effect may be further enhanced.

The photocatalyst member carried by the corrugated structure used in the present invention is one that promotes its catalytic reaction by light irradiation. The type is not limited. For example, those disclosed in JP-A-2-273514 can be cited, and metal oxides such as zinc oxide, tungsten trioxide, titanium oxide, and cerium oxide are preferable. Among these, titanium oxide is It is a particularly preferable material in consideration of, for example, structural stability, ability as a photoreactive semiconductor, and safety in handling. As titanium oxide, in addition to conventional general-purpose titanium oxide, hydrous titanium oxide, metatitanic acid, orthotitanic acid,
Includes all titanium oxides or hydroxides called titanium hydroxide. As a method for producing titanium oxide,
A method of hydrolyzing titanyl sulfate, titanium chloride, an organic titanium compound or the like in the presence of seeds for nucleation as necessary (hydrolysis method). A method of neutralizing by adding an alkali agent to titanium, an organic titanium compound, etc. (neutralization method),
Examples include a method of firing titanium oxide obtained by hydrolysis and neutralization (firing method), and titanium oxide obtained by any manufacturing method can be used.

The metal or metal oxide such as platinum or ruthenium oxide is supported on the semiconductor in order to further enhance the photocatalytic ability of the semiconductor. These may be carried on the surface or may be mixed in the layer. Further, it may be carried on semiconductor fine particles introduced into the layer. In addition, these are carried out by a conventional technique such as an impregnation method, an ion exchange method, a photoelectric deposition method, and a kneading method.

The corrugated member in the photocatalyst member of the present invention is made of a commonly used material. Although the type is not limited, for example, various types of paper, nonwoven fabric, sheets such as resin films, ceramic, glass, metal, and wood can be used. In the present invention, a fibrous sheet carrying a photocatalyst, such as paper, nonwoven fabric, or cloth, has a porous structure, and has many opportunities for contact between the photocatalyst and the odorous substance.

In order to make a photocatalyst member of the present invention by supporting a photocatalyst on the above-mentioned various materials, for example, various kinds of sheets such as paper, non-woven fabric, resin film, etc.
After being supported by various methods such as impregnation and kneading, it is processed into a corrugated shape to obtain a photocatalyst member. Further, a photocatalyst such as titanium oxide or zinc oxide may be used as a constituent material of the corrugate as it is. In addition, various photocatalysts may be supported on a structure previously formed as a corrugated member. Further, it is more effective to use an adsorbent such as activated carbon, activated carbon fiber, silica gel, or a catalyst such as manganese dioxide as a constituent material of the corrugate, or to use in combination with a photocatalyst.

The corrugated structure used for the photocatalyst member of the present invention is manufactured in accordance with JIS Z 1516-1995 "Corrugated cardboard for exterior use". For example, a corrugated block is manufactured by sequentially laminating a single corrugated cardboard having a middle lining bonded onto a liner with an adhesive (see FIG. 1). The corrugated photocatalyst member may be formed by cutting the liner surface of the corrugated block obliquely at a certain angle.

In the photocatalyst member of the present invention, the light source arrangement for exciting the photocatalyst may be either leeward or leeward of the photocatalyst member. Also, both of them may be used. In addition, the photocatalyst member may be arranged so as to surround the light source.

[0029]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

The production example of the photocatalyst sheet (raw material) and the photocatalyst corrugate used in the photocatalyst member of the present invention will be described.

"Production of photocatalyst sheet (raw material)" 100 parts by weight of titanium oxide having photocatalytic ability was added to water, and dispersed using a mixer. Was added to form an aggregate of titanium oxide, which was referred to as an aggregate aqueous dispersion A.

As a support-forming component, 0.5 denier ×
A 5 mm polyester fiber and a low-melting heat-fusible polyester fiber having a core-in-sheath structure of 2 denier × 5 mm were added to water in equal parts by weight, stirred and dispersed to obtain a support-forming component dispersion B.

The dispersion A and the dispersion B are mixed so that the weight ratio of titanium oxide to the support-forming component is 1: 9, and the total solid content is adjusted to 0.2% by weight.
The sheet was formed into a sheet by a round paper machine, and dried at 120 ° C. to prepare a photocatalyst sheet (raw sheet) having a basis weight of 100 g / m ² .

[Production of corrugated block] The photocatalyst sheet (raw material) produced as described above is laminated with a liner and a lining in order according to JIS Z1516-1995 "Corrugated cardboard for exterior". 2.5m pitch
m, 3.5 mm and 5.8 mm corrugated blocks (see FIG. 1) were produced. Corrugated blocks of Preparation Examples 1, 2 and 3 were prepared in the order of small pitch.

Example 1 The liner surface of the corrugated block of Preparation Example 1 was 45
The oblique angle of the liner with respect to the opening surface of the cell is 45 °, the thickness is 3.5 mm, the length is 200 mm,
A photocatalyst member having a height of 100 mm was manufactured and used as the photocatalyst member of Example 1.

Examples 2 to 6 With respect to the liner surface of the corrugated block of Preparation Example 2, 7
Obliquely cut at angles of 0, 60, 45, 30 and 20 °, the angle of the liner with respect to the opening of the cell is 2
Photocatalyst members having 0, 30, 45, 60, and 70 °, a thickness of 7 mm, a length of 200 mm, and a height of 100 mm were produced.
The photocatalyst members of Examples 2 to 6 were set in ascending order of the angle of the liner with respect to the opening surface of the cell.

Examples 7 and 8 The corrugated block of Preparation Example 3
Then, the photocatalyst member was manufactured in which the liner was inclined at an angle of 45 ° with respect to the opening surface of the cell, the thickness was 7 mm and 8.5 mm, the length was 200 mm, and the height was 100 mm.
The photocatalyst members of Examples 7 and 8 were used in ascending order of thickness.

Comparative Examples 1 to 3 The corrugated blocks of Preparation Examples 1 to 3 were cut at right angles to the liner surface, and were 7 mm in thickness, 200 mm in length, and 10 in height.
A 0 mm photocatalyst member was produced. The pitch at this time is 2.
5 mm, 3.5 mm and 5.8 mm. The photocatalyst members of Comparative Examples 1 to 3 were used in ascending order of pitch.

Examples 9 and 10 As shown in FIGS. 3 and 4, the photocatalyst members of Examples 3 and 5 were laminated by bringing the cell opening surfaces into contact with each other by two methods, thereby producing a composite photocatalyst member. The multilayer photocatalyst members of Examples 9 and 10 were set in ascending order of the figure.

Example 11 As shown in FIG. 5, the photocatalyst members of Example 1 and Comparative Example 2 were laminated with the liner aligned and the cell opening surfaces in contact with each other. Was prepared.

Example 12 As shown in FIG. 6, the photocatalyst members of Example 1 and Comparative Example 2 were stacked with the liner position shifted by half a pitch and the cell opening surfaces in contact with each other. A photocatalyst member was produced.

Example 13 As shown in FIG. 7, the photocatalyst members of Example 1 and Comparative Example 1 were laminated with their cell opening surfaces in contact with each other to produce a multilayer photocatalyst member of Example 13.

EXAMPLE 14 As shown in FIG. 8, the two photocatalyst members of Example 1 were stacked with the liner positions shifted by a half pitch and the cell opening surfaces were in contact with each other. Was prepared.

Example 15 As shown in FIG. 9, two photocatalyst members of Example 1 were stacked with their liners upside down, the liners were aligned, and the cell opening surfaces were in contact. A layer photocatalyst member was produced.

Example 16 As shown in FIG. 10, the two photocatalyst members of Example 1 were stacked upside down with the liner position shifted by half a pitch and the cell opening surfaces in contact. Was produced.

Example 17 As shown in FIG. 11, two photocatalyst members of Example 1 were stacked upside down, with a cell opening surface being spaced apart by 2 mm, to obtain a multilayer photocatalyst member of Example 17. Produced.

COMPARATIVE EXAMPLE 4 As shown in FIG. 12, two photocatalyst members of Comparative Example 2 were stacked with the liner positions shifted by half a pitch and the cell opening surfaces were brought into contact with each other. Was prepared.

Comparative Example 5 As shown in FIG. 13, two photocatalyst members of Comparative Example 2 were stacked with the liner position shifted by half a pitch and the interval between the cell opening surfaces was set to 2 mm. A photocatalyst member was produced.

Comparative Example 6 As shown in FIG. 14, the photocatalyst members of Comparative Example 1 and Comparative Example 2 were laminated with their cell opening surfaces in contact with each other to produce a multilayer photocatalyst member of Comparative Example 6.

The photocatalyst members obtained in the examples and comparative examples were tested by the following methods to evaluate the performance.

<Deodorizing Performance> The photocatalyst member was allowed to stand at the bottom of a 5.6 liter closed container equipped with a 6 W black lamp so that the distance from the black lamp was 2 cm.
100 ppm of acetaldehyde was injected into the container, and the black lamp was turned on to irradiate ultraviolet rays.
After a minute, the acetaldehyde concentration (ppm) in the container was measured by gas chromatography.

<Leakage of Excitation Light> A straight tube type black light (power consumption: 6 W, tube diameter: 15.5 mmφ) is installed so as to extend in the length direction of the photocatalyst member and at the center in the height direction. The light was turned on, and the leakage of ultraviolet light to the opposite side of the photocatalyst member was measured with an ultraviolet illuminometer. There were three measurement positions near the center in the height direction and near both ends (see FIG. 15).

<Air permeability> The pressure loss of the photocatalyst members of Examples and Comparative Examples was measured in accordance with JIS-B-9908. The smaller the pressure loss, the better the air permeability.

Tables 1 and 2 show the results of the tests performed according to the above-mentioned methods and the evaluation of the performance.

[0055]

[Table 1]

[0056]

[Table 2]

From the results in Tables 1 and 2, the following can be understood.

The angle is 90 °, the thickness is 7 mm, and the pitch is 2.
Compared with Comparative Examples 1 to 3, which were changed to 5 mm, 3.5 mm, and 5.8 mm, the angle was 20 ° to 70 °, the thickness was 3.5 to 8.5 mm, and the pitch was 2.5 mm. 5
mm and 5.8 mm, respectively.
No. 8 shows that a photocatalyst member excellent in deodorization performance can be obtained in each case, despite the fact that there is almost no difference in air permeability.
In addition, there is no leakage of the excitation light in the central portion where the ultraviolet intensity is high, except for Examples 6 and 7, indicating that the effective use of the excitation light is improved. In Examples 9 to 17 in which the above-described single-layer examples were appropriately combined, a photocatalyst member having more excellent deodorization performance was obtained as compared with Comparative Examples 4 to 6 in which two single-layer comparative examples were stacked. I understand. In addition, there is no leakage of the excitation light in the central portion where the ultraviolet light intensity is high, and it can be understood that the effective use of the excitation light is extremely improved.

[0059]

According to the present invention, a corrugated photocatalyst member carrying the photocatalyst of the present invention and having a liner surface at an oblique angle with respect to the cell opening surface, or one of the constituent elements of the corrugated photocatalyst member, The photocatalyst member included as a part,
Compared with the conventional photocatalyst member, the effective use of the excitation light is improved and the photocatalyst member having excellent deodorization performance is obtained, though there is almost no difference in air permeability. In particular, a multilayer photocatalyst member obtained by laminating two or more corrugated photocatalyst members makes it possible to use the excitation light very effectively, and to obtain a photocatalyst member with even better deodorization performance.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a corrugated photocatalyst member according to the present invention and an embodiment of a corrugated block as a base thereof.

FIG. 2 is a front view, a side view, and a bottom view showing one embodiment of the corrugated photocatalyst member of the present invention.

FIG. 3 is a side view of a multilayer photocatalyst member according to a ninth embodiment of the present invention.

FIG. 4 is a side view of a multilayer photocatalyst member according to a tenth embodiment of the present invention.

FIG. 5 is a side view of a multilayer photocatalyst member according to an eleventh embodiment of the present invention.

FIG. 6 is a side view of a multilayer photocatalyst member according to a twelfth embodiment of the present invention.

FIG. 7 is a side view of a multilayer photocatalyst member according to a thirteenth embodiment of the present invention.

FIG. 8 is a side view of a multilayer photocatalyst member according to a fourteenth embodiment of the present invention.

FIG. 9 is a side view of a multilayer photocatalyst member according to Embodiment 15 of the present invention.

FIG. 10 is a side view of a multilayer photocatalyst member according to Example 16 of the present invention.

FIG. 11 is a side view of a multilayer photocatalyst member according to a seventeenth embodiment of the present invention.

FIG. 12 is a side view of the multilayer photocatalyst member of Comparative Example 4 of the present invention.

FIG. 13 is a side view of the multilayer photocatalyst member of Comparative Example 5 of the present invention.

FIG. 14 is a side view of the multilayer photocatalyst member of Comparative Example 6 of the present invention.

FIG. 15 is a diagram illustrating a method of measuring leakage of excitation light in an example of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 Liner surface of corrugated block 2 Example of corrugated photocatalyst member whose liner surface is at an oblique angle with respect to cell opening surface 3 Spacer 4 Black light 5 Photocatalyst member of examples and comparative examples 6 Measurement of ultraviolet illuminometer Position X Oblique angle of liner with respect to cell opening surface Y Pitch Z Thickness a Length b Height

Claims (7)

[Claims] 1. A corrugated photocatalyst member carrying a photocatalyst, wherein the liner surface has an oblique angle with respect to the opening surface of the cell. 2. A photocatalyst member that carries a photocatalyst and includes, as a component, a corrugated photocatalyst member having a liner surface having an oblique angle with respect to an opening surface of a cell. 3. The photocatalyst member according to claim 1, wherein the corrugated photocatalyst member has an oblique angle of 30 ° to 60 °. 4. The corrugated photocatalyst member is characterized in that the relationship between the oblique angle (X), pitch (Y) and thickness (Z) with respect to the opening surface of the cell is Y ≦ ZcosX. The photocatalyst member according to claim 1, 2 or 3. 5. The photocatalyst member according to claim 2, wherein two or more corrugated members are laminated. 6. A corrugated photocatalyst member having the same shape and
3. The sheet according to claim 2, wherein the sheets are stacked upside down.
The photocatalyst member according to 3, 4 or 5. 7. The photocatalyst member according to claim 1, wherein at least a part of the corrugated photocatalyst member constituting the photocatalyst member is formed of a fibrous sheet carrying a photocatalyst.
7. The photocatalyst member according to 5 or 6.