JPH10290981A - Photocatalyst purifying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photocatalyst purifying device which make it possible to decompose and purify suspended materials on a water by irradiating transparent members particularly from perpendicularly above these members, providing the perpendicular layer parts thereof with, for example, glass solid parts and activating catalyst layers by the cast light while holding the members in a stable posture. SOLUTION: The floating bodies consisting of the transparent members are disposed in the upper part of the device for decomposing and purifying the suspended materials on the water by light. Weights are disposed in their perpendicular lower parts to stabilize the direction on the water. While the floating bodies are kept floated, the photocatalyst coating layers 2 disposed on the surface of at least the perpendicular parts are irradiated with the light from the perpendicular upper parts of the transparent members to activate the photocatalyst, by which the suspended materials on the water are decomposed and purified. The photocatalyst coating layers 2 are arranged on at least the surfaces of the solid glass bodies and/or the surfaces of the perpendicular lower parts of the hollow glass bodies 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocatalyst purifying device, and more particularly to a device for irradiating light from vertically above a transparent member and providing a weight, for example, a solid glass portion as a weight below the transparent member to maintain a stable posture. The present invention relates to a photocatalyst purification device that activates a catalyst layer by light irradiated while decomposing and purifying suspended matters on water.

[0002]

2. Description of the Related Art Regulations on various harmful substances, such as industrial wastes, that cause environmental pollution become stricter day by day.
Technology development for the countermeasures is being actively conducted. As a technique using a photoreaction, which is a typical treatment method, use of a photocatalyst has attracted attention. This utilizes the effect of promoting the activation of the catalyst component in a relatively low temperature range of light itself. At this time, many attempts have been made to collect and collect contaminants, which normally exist in the atmosphere in a dilute state, in a container and to treat the contaminants, or to distribute the contaminants to the container and to develop a photoreaction. Recently, a cost-effective apparatus for decomposing and purifying these harmful substances with respect to substances in a specific environment using a photocatalyst has been studied.

[0003] As a method of using the photocatalyst, studies have been made in various fields on whether the photocatalyst can be used for purification of suspended matters on water such as oil. As a known technique in this field, for example, JP-A-5-49861 discloses a protective layer transparent to light,
There is disclosed an environmental purification device having a multi-layer structure composed of a thin layer of a carrier carrying a photocatalyst with a porous layer having a selective permeability or adsorption to a specific substance.

[0004] On the other hand, there has been studied a method in which titanium oxide is coated on the surface of a water-based oil or the like, which is coated with titanium oxide, and the glass is scattered on the sea. This hollow glass has a spherical shape, and titanium oxide is coated on the entire surface of the sphere (see FIG. 7). However, in this technique, if suspended matter such as oil completely adheres to the surface of the titanium oxide, ultraviolet rays (sunlight) do not irradiate the titanium oxide, so that a purification action cannot be obtained. In other words, since it is spherical, it rotates in water while floating, and the entire surface of the titanium oxide is easily covered with a floating substance such as oil. If the floating substance such as oil completely adheres to the surface of the titanium oxide, the entire surface of the hollow glass becomes UV light (sunlight) is not applied because the structure is coated with titanium oxide. Therefore, development of a photocatalyst purifying apparatus capable of decomposing and purifying floating substances on water such as oil with a photocatalyst layer having a more stable posture and effectively disposed has been desired.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to examine a device capable of using a photocatalyst at low cost for a long time, maintain a more stable posture on water, and make the transparent body a floating substance. An object of the present invention is to provide a photocatalyst purifying device that can continuously emit light without being covered.

Another object of the present invention is to improve the stability of the posture on water in the past. However, this improvement was examined, the shape was made into a teardrop shape, and the weight for stabilization was examined. And to provide a photocatalyst purification device capable of preventing adhesion by contaminants. Still another object of the present invention is to provide a photocatalyst purifying apparatus capable of studying a method for coating the catalyst component and maintaining a long-time photocatalytic reaction on water.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a device for decomposing and purifying floating substances on water by light, in which a floating body made of a transparent member is disposed at an upper part, and a weight is disposed at a vertically lower part thereof. While stably floating on the water, the photocatalyst layer disposed on at least the vertically lower surface is irradiated with light from the vertically upper part of the transparent member to activate the photocatalyst, and decompose the suspended matter on the water. This is achieved by a photocatalytic purifier characterized by purifying.

Another object of the present invention is to provide an apparatus for decomposing and purifying suspended matters on water by light, wherein a hollow glass body of a transparent member is provided on an upper part, and a solid glass body is provided vertically below the transparent glass body. At least the solid glass body surface and / or
Alternatively, the photocatalyst layer disposed on the vertically lower surface of the hollow glass body is irradiated with light from the vertically upper part of the hollow glass body to activate the photocatalyst, and decompose and purify suspended matters on water. This is also achieved by a photocatalytic purification device.
Furthermore, the above object is also achieved by a photocatalyst purifying device, wherein the transparent member is provided with a photocatalyst layer on a tapered portion having a teardrop shape and at least a gradually decreasing cross-sectional diameter.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a surface that always comes out of the water and a surface that comes in contact with the water are provided. The surface that comes out of the water transmits ultraviolet rays (sunlight), and the surface that comes in contact with the water is coated with titanium oxide or the like. Photocatalyst purification carrier. Thus, the light from vertically above the transparent member activates the photocatalyst in the vertically lower portion, thereby purifying the surrounding oil and the like. In addition, since there is a weight (solid portion of glass) vertically below, the posture is stable, and it is possible to prevent oil or the like from adhering to the vertically upper portion due to rotation.

In addition, the photocatalyst device can be manufactured more easily by forming it into a teardrop shape. further,
The generation of the moving force of the substance enables continuous processing. That is, the photocatalyst portion of the transparent body, which is coated on the surface of the transparent body in the water, is decomposed and purified, and the substance concentration is low. For this reason, a substance flow is generated from the peripheral high concentration side, is supplied to the surface coating portion as a continuous flow, and decomposition / purification by a photoreaction proceeds.

Although the mechanism of this photoreaction is not clear, it is conceivable that light having a wavelength corresponding to the catalyst component is absorbed and excited to activate the photocatalyst and promote oxidation / reduction reactions as a catalytic reaction. The photocatalyst layer of the present invention includes, for example, titanium oxide, strontium titanate, zinc oxide, tungsten oxide, cadmium sulfide, molybdenum sulfide, cadmium telluride, cadmium selenium, copper oxide, iron oxide, tin oxide, gallium arsenide, silicon, and the like. What is necessary is just to coat | cover the thing selected from the substance which promotes a photoreaction, and just to form a film. The supported metal or metal oxide may be, for example, gold, platinum, palladium, rhodium, ruthenium, or a composite oxide thereof. Hereinafter, the present invention will be further described with reference to the accompanying drawings.

[0012]

EXAMPLE In this example, as shown in FIG. 1, a teardrop-shaped hollow glass 1 was used as a catalyst carrier in a floating substance 3 such as oil.
As shown in the figure, a surface that comes into contact with water is coated with a titanium oxide film 2 as shown in the figure, and sunlight 4 is basically radiated from above the teardrop-shaped hollow glass 1. In addition, as shown in FIG. 2, the directional stability on water was tested by disposing a solid teardrop-shaped hollow glass 5 as a weight below the hollow teardrop-shaped hollow glass 1. Hereinafter, test results will be described as specific examples according to the type of FIG.

In this embodiment, the contact portion of the teardrop-shaped hollow glass in water is dip-coated with titanium oxide sol and dried at 200 ° C. The size of the teardrop-shaped hollow glass was set to 15 mm in the longitudinal direction and 10 mm in the radial direction. Then, as shown in FIG. 3, a coated teardrop-shaped hollow glass 7 was put into a water tank containing sewage 8 so as to cover the water surface. At this time, even if it was thrown in at random, the posture in the fixed direction could always be ensured because of the weight, and it floated uniformly over the water surface. Black light 6 (ultraviolet light) was applied from above the water tank to purify water by a photocatalytic effect. Thereafter, the transmittance of the purified sewage was measured by a spectrophotometer. FIG. 4 shows the results. The transmittance was higher in a shorter time when the teardrop-shaped hollow glass was used for the carrier than when the spherical glass was used. As a result, the teardrop-shaped hollow glass carrier has a high purifying ability and can maintain the purifying ability for a long time.

The reason why the tapered portion in the teardrop shape of this embodiment is always on the water side and the posture is stabilized is considered as follows. FIGS. 7A and 7B show the displacement of the position of the center of gravity depending on the shape. Since the carrier is floating on the water, its buoyancy and the point of action correspond to the weight and the center of gravity of the fluid displaced by the object. In the case of a sphere (FIG. 7A), it is at the center of the sphere, and in the case of a teardrop, it is at a position displaced more than in the case of a sphere as shown in FIG. 7B. For this reason, in FIG.
Although the position of the center of gravity is lower than that of FIG. 7 (e), the length protruding above the water surface is h (1)> h (2), and FIG. 7 (e) is more stable. In addition, in FIG. 7D, the right side has large buoyancy and rotates. As a result, in any case, a stable state is obtained in FIG.

Next, as another embodiment, an example in which the shape of the hollow glass is spherical and the hollow glass used as the weight is spherical will be described. 5 and 6 show a carrier in which a solid glass sphere is attached as a weight to a hollow glass sphere. In FIG. 5, a hollow glass sphere 9 is integrally provided with a solid glass sphere 10, and a titanium oxide film 2 is arranged in a portion in water. Traditionally,
As shown in FIG. 7, the titanium oxide film 2 is disposed on the entire surface of the hollow glass sphere 9, and since there is no weight portion, the sphere is easy to rotate. Had trouble. On the other hand, in the present embodiment, since the floating is maintained while maintaining the stable direction without such rotation, the light shielding obstacle due to the adhesion of the contaminant does not occur.

Further, as shown in FIG. 6, a light-transmitting titanium oxide sufficiently thin enough to transmit light to the surface of the hollow glass sphere 9 in order to prevent contaminants from adhering to a portion of the water surface. A membrane 11 can be provided. As a result, it was found that the adhesion of contaminants on the surface that shields the light irradiation could be almost completely prevented, and the purifying action was maintained for a long time.

[0017]

According to the present invention, it is possible to activate the photocatalyst by irradiating light from above the transparent member vertically, and to decompose and purify pollutants. In addition, the posture is stabilized by the weight, and adhesion of contaminants due to rotation is prevented. Further, by forming the shape into a teardrop, it is possible to manufacture the device by a low-cost and relatively simple process.

[Brief description of the drawings]

FIG. 1 is a view showing a teardrop-shaped hollow glass sphere according to an embodiment of the present invention.

FIG. 2 is a view showing a teardrop-shaped hollow glass sphere and a solid glass sphere according to an embodiment of the present invention.

FIG. 3 is a view showing a state of being put into a sewage tank according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a relationship between an ultraviolet irradiation time and a transmittance according to a shape of a glass body according to an example of the present invention.

FIG. 5 is a view showing an example using a hollow glass sphere and a solid glass sphere as another embodiment of the present invention.

FIG. 6 is a view showing an example in which a permeable titanium oxide film is disposed on a hollow glass sphere as another embodiment of the present invention.

FIG. 7 is an explanatory view of the stability of the teardrop-shaped hollow glass sphere of the present invention on water, wherein (a) the center of gravity of the comparative spherical glass, (b) the center of gravity of the teardrop-shaped hollow glass sphere, and (c) the teardrop Unstable position of hollow glass sphere, (d) Unstable position of hollow glass sphere, (e)
It is a figure which shows the stable position of a teardrop type hollow glass sphere.

FIG. 8 is a diagram showing an example in which a photocatalytic film is arranged on the entire surface of a conventional spherical hollow glass.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Teardrop type hollow glass sphere 2 ... Titanium oxide film 3 ... Floating substance such as oil 4 ... Sunlight 5 ... Teardrop type hollow glass sphere (solid) 6 ... Ultraviolet ray 7 ... Teardrop type glass carrier 8 ... Sewage 9 ... hollow glass sphere 10 ... solid glass sphere 11 ... permeable titanium oxide film

Claims (3)

[Claims] 1. A device for decomposing and purifying floating substances on water by light, wherein a floating body made of a transparent member is arranged on an upper part,
At least a photocatalyst layer disposed on the surface of the vertical lower portion is irradiated with light from the vertical upper portion of the transparent member to activate the photocatalyst while arranging a weight below the vertical portion to stabilize and float the direction above water. A photocatalyst purification apparatus characterized in that it is decomposed to decompose and purify suspended matters on water. 2. A device for decomposing and purifying suspended matter on water by light, comprising: a hollow glass body of a transparent member at an upper part; and a solid glass body at a vertically lower part thereof, wherein at least the solid glass body is disposed. The photocatalyst layer disposed on the surface of the glass body and / or the vertically lower surface of the hollow glass body is irradiated with light from the vertically upper part of the hollow glass body to activate the photocatalyst, thereby decomposing and purifying suspended matters on water. A photocatalyst purification device characterized by the above-mentioned. 3. The transparent member according to claim 1 or 2,
An apparatus for purifying a photocatalyst, wherein a photocatalyst layer is disposed on a tapered portion having a teardrop shape and at least a gradually decreasing cross-sectional diameter.