JPH06157002A - Photodecomposition apparatus - Google Patents

Abstract

PURPOSE:To efficiently make reactional light react with a photocatalyst in a solution without leaking the reactional light to the outside by reducing the refractive index of an inner wall of a reactional vessel from that of a reactional solution. CONSTITUTION:This photodecomposition apparatus 1 is equipped with a vessel 4 formed from a Teflon(R) pipe having about 100mm diameter and about 2m length, a window 7 of a quartz glass plate at the lower end thereof and a valve 11 for holding and taking out a reactional product 6 in the upper part of the vessel. A solution 3 prepared by dispersing a photocatalyst 2 of SrTiO3/NiO in water is introduced from an injection port 10. The refractive index of the solution 3 is about 1.33 and the refractive index of the inner wall of the vessel 4 is about 1.30. The reactional light 5' incident thereon from the window 7 propagates while totally reflecting from the wall surface of the Teflon(R) and the reflection efficiency can be raised. The produced H2 and O2 gases are taken out through the valve 11 to the outside. A taking-out port 9 is located in the upper part of the vessel and the incident window 7 of the reactional light 5 is located on the lower side. This is because if the reactional product 6 having a low refractive index is collected near the window 7, the light 5 from a light source is reflected to lower the reactional efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photolysis device for decomposing a solution using reaction light to obtain a reaction product.

[0002]

2. Description of the Related Art Active use of solar energy has been promoted due to the problem of global warming caused by depletion of fossil energy and accumulation of carbon dioxide. Among them, as a method for obtaining a product by photolyzing a solution with sunlight, as shown in FIG.
For example, a photocatalyst 2 such as SrTiO ₃ / NiO is dispersed in water 3 and put in a reaction container 40, and light is incident through a window 7 to decompose water by a photochemical reaction to obtain a product 6 of H ₂ and O ₂ . .

[0003]

In order to efficiently carry out the above-mentioned photoreaction, it is preferable that the catalyst in the container is uniformly exposed to light. However, in the conventional device, not only the incidence of light is limited by the size of the window 7, but also the light is absorbed and scattered by the catalyst in the vicinity of the window and becomes a so-called blind spot away from the window or with respect to the window. Light could not reach where it was, and could not be efficiently photolyzed. An object of the present invention is to provide a photolytic device that solves such problems.

[0004]

The present invention is a photolytic apparatus having a cylindrical container for irradiating a solution in which a photocatalyst is dispersed with reaction light and decomposing the solution to obtain a reaction product. The inner wall of the container is made of a material having a refractive index lower than that of the solution, a valve for taking out a reaction product is provided on the upper part of the container, and reaction light is incident from a lower end surface of the container.

Further, according to the present invention, a solution in which a photocatalyst is dispersed is irradiated with reaction light, and the solution is decomposed to obtain a reaction product. A decomposition device, wherein an inner wall of the container is formed of a material having a lower refractive index than the solution, a valve for taking out a reaction product is provided at an upper portion of the container, and reaction light is photodegraded from an end surface of the container. It is a device.

Here, it is preferable that the container or the inner wall thereof is made of Teflon.

[0007]

According to the above construction, in the photolysis device according to the present invention, the inner wall of the reaction vessel is smaller than the refractive index of the solution, so that the inside of the vessel is kept at a corner without leaking the reaction light to the outside. It can be propagated to various areas, and can efficiently act on the photocatalyst in the solution. Further, the reaction product is taken out from the central upper part of the container bent in an inverted U shape, while the incident window of the reaction light to the container and the reflecting plate on the opposite side are provided on the lower side of the container, Leakage due to reflection and scattering of reaction light can be prevented, and reaction efficiency can be improved.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description. FIG. 1 is a cross-sectional view showing the structure of this embodiment, in which the photolytic device 1 has a diameter of 100
a container 4 formed of a Teflon pipe having a length of 2 mm and a length of 2 mm;
A quartz glass plate window 7 is attached to the lower end thereof, and a valve 11 for holding and taking out the reaction product 6 is attached to the upper portion of the container. The solution 3 in which the SrTiO ₃ / NiO photocatalyst 2 is dispersed in water is introduced from the injection port 10.

Here, the refractive index of the solution 2 (water) is approximately 1.
33, since the inner wall of the container 4 is made of Teflon having a refractive index of about 1.30, the reaction light 5 ′ incident from the window 7 propagates while being totally reflected by the wall of the Teflon, so the reaction light is inside the container. Can be propagated to every corner and the reaction efficiency can be improved. The produced H ₂ and O ₂ gases are collected in the upper part of the reaction vessel and taken out through the valve 11. The outlet 10 is located at the top of the container, and the window 7 through which the reaction light 5'is incident is located at the bottom. This is because if the reaction product 6 having a low refractive index accumulates in the vicinity of the window 7, the light 5 from the light source such as the sun or a xenon lamp is reflected and the reaction efficiency decreases.

When a container having the same size as the Teflon pipe container was made of quartz glass and stainless steel and water was photolyzed for each, the Teflon pipe device was about the same as other cases. It was possible to obtain 10 times the reaction efficiency.

FIG. 2 is a cross-sectional view showing the structure of another embodiment. The photolysis device 1 comprises a container 4 formed by bending a Teflon pipe having a diameter of 100 mm and a length of 2 m into a high inverted U-shape at the center. A quartz glass plate window 7 is provided at one end of the quartz glass plate, and a quartz glass plate is provided with a reflecting plate 8 at the other end thereof, and a valve 11 for holding and taking out the reaction product 6 is provided above the container. Installed. SrTiO ₃ / Ni
The solution 3 in which the O photocatalyst 2 is dispersed in water is introduced from the inlet 10.

The reaction light 5'incident from the window 7 propagates while being totally reflected by the wall surface of Teflon, is reflected by the reflection plate 9 at the other end of the container, and propagates again in the solution, further increasing the reaction efficiency. be able to. The produced H ₂ and O ₂ gases are collected in the upper part of the reaction vessel and taken out through the valve 11. The outlet 10 is located above the container, and the window 7 through which the reaction light 5'is incident and the reflector 8 provided at the other end are located below. This is because if the product accumulates in the vicinity of the reflection plate 8, the reaction light 5'is diffusely reflected and the reaction efficiency is reduced.

In the above embodiment, the case of decomposing water into H ₂ and O ₂ was explained, but in addition to this, a CO ₂ aqueous solution is added to CH ₃
The OH and CH _{4 'The} N ₂ aqueous solution can be decomposed in the same manner to NH ₃ and N ₂ H _4. All photocatalysts are P
_{t / TiO 2 'SrTiO 3'} SrTiO 3 / NiO, K 4 N
b ₆ O ₁₇ / NiO or Rh / TiO ₂ can be applied.

[0014]

As described in detail above, according to the present invention, since the inner wall of the reaction vessel is constructed to have a smaller refractive index than the solution, the inside of the vessel can be kept at a corner without leaking the reaction light to the outside. It can be propagated to various areas, and can efficiently act on the photocatalyst in the solution.

Furthermore, the reaction product is taken out from the central upper part of the container bent in an inverted U shape, while the incident window of the reaction light to the container and the opposite reflection plate are provided on the lower side of the container. Therefore, light leakage due to reflection and scattering of reaction light can be prevented, and reaction efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a configuration of an example of the present invention.

FIG. 3 is a cross-sectional view showing a configuration of a conventional example.

[Explanation of symbols]

 1, 1 ': photodecomposition device 2: photocatalyst 3: solution 4,40: container 5,5: light 6: product 7: window 8: reflector 9: outlet 10: inlet 11: valve

Front Page Continuation (72) Inventor Yoshio Suzuki 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Steel Pipe Co., Ltd.

Claims (3)

[Claims] 1. A photolysis device having a cylindrical container for irradiating a solution in which a photocatalyst is dispersed with reaction light to decompose the solution to obtain a reaction product, wherein the inner wall of the container is the A photolysis device, which is formed of a material having a refractive index lower than that of a solution, a valve for taking out a reaction product is provided in an upper portion of a container, and reaction light is incident from a lower end surface of the container. 2. A reverse U for obtaining a reaction product by irradiating a reaction light to a solution in which a photocatalyst is dispersed to decompose the solution.
A photolysis device having a cylindrical container bent in a letter shape, wherein an inner wall of the container is formed of a material having a lower refractive index than the solution, and a valve for taking out a reaction product is provided on an upper part of the container. The photolytic device characterized in that the reaction light is incident from the end face of the container. 3. The photolysis device according to claim 1, wherein the container or the inner wall thereof is made of Teflon.