Optical reaction device

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to a photoreactive device that obtains a reaction product from a compound by a redox reaction using a photoreaction.

【0002】

[Conventional technology]

TiO₂When a semiconductor particle such as a semiconductor particle is excited by irradiating it with light having an energy equal to or greater than its band gap, an electron is generated in the conduction band and a hole is generated in the valence band.₂Or H₂It is known that it is possible to decompose O and generate hydrogen.

【0003】

Conventionally, as a method of utilizing a semiconductor photocatalytic reaction, one method of dispersing photocatalytic particles in a solution in a reaction vessel has been known, and a thin film of a substance having photocatalytic activity is at least used for the activity of the substance. A method of coating the surface of particles, flakes, or fibers of a material transparent to the required light is described in Japanese Patent Application Laid-Open No. 63-97274. The former method has a problem that the photocatalytic particles are deposited, the photocatalyst involved in the reaction is limited to the surface portion of the sedimentation, and the efficiency of the photocatalytic reaction is lowered. Further, when the dispersed photocatalyst particles are mechanically agitated to prevent deposition, there is a problem that the light introduced into the reaction vessel cannot be effectively used due to shading by a stirring device or the like. In the latter method, it is difficult to coat the particles, flakes, and fibers described in JP-A-63-97274 with high density, and the substances having photocatalytic activity that can be coated are limited. There was a problem.

【0004】

[Problems to be Solved by the Invention]

Therefore, it is necessary to efficiently introduce light into the reaction vessel and effectively irradiate the semiconductor photocatalyst particles with light.

【0005】

An object of the present invention is to provide a photoreactor having high redox reaction efficiency by utilizing an inorganic semiconductor photocatalyst.

【0006】

[Means for solving problems]

In order to solve the above problems, (1) the structure is such that a polymer thin film carrying a semiconductor photocatalyst is provided in the reaction vessel, or a polygonal shape having a wall of the polymer thin film carrying a semiconductor photocatalyst. The structure is such that an aggregate of cells is formed in a reaction vessel. (2) An optical fiber having a light collecting portion at the other end is loaded into each cell separated by a polymer thin film, and the structure is such that light is guided into each cell.

【0007】

[Action]

The photocatalytic reaction in the reaction solution is CO₂As an example, the photocatalyst is excited by light energy and decomposes water by holes in the valence band to generate oxygen and hydrogen ions. The electrons generated in the conduction band are hydrogen ions and CO₂Contributes to the reaction of CO₂Is fixed.

【0008】

By supporting the semiconductor photocatalyst particles on a polymer thin film and using them, suspension by the semiconductor photocatalyst particles can be prevented and light attenuation in the solution can be almost eliminated. As a result, the amount of the semiconductor photocatalyst excited by the light energy can be increased, and the reaction efficiency can be increased.

【0009】

[Example]

FIG. 1 is a longitudinal side view of an embodiment of the photoreactor of the present invention.

【0010】

In FIG. 1, a light dispersion device 2 is installed above the redox reaction vessel 3, and can be removed from the redox reaction vessel 3. A condenser 1 is attached to the light disperser 2. The redox reaction vessel 3 is provided with an injection port 6 for introducing the reaction solution into the vessel and an outlet 7 for transferring the compound produced after the reaction to the separation treatment step. A plurality of plate-shaped polymer thin films 4 carrying semiconductor photocatalyst particles are installed in the redox reaction vessel 3.

【0011】

A plurality of optical fibers 5 having different lengths are attached to the optical dispersion device 2, and the other end of the optical fiber 5 portion is inserted into the redox reaction vessel 3.

【0012】

The reaction solution is introduced into the redox reaction vessel 3 from the injection port 6. The light collected by the condenser 1 is sent to a plurality of optical fibers 5 by the optical dispersion device 2. The light emitted from the optical fiber 5 excites the semiconductor photocatalytic particles on the polymer thin film 4, and a photocatalytic reaction occurs. In order to separate the produced reactant, the solution in the redox reaction vessel 3 is taken out from the outlet 7.

【0013】

Since the lengths of the plurality of optical fibers 5 are different, the entire inside of the redox reaction vessel 3 can be irradiated with light.

【0014】

The polymer thin film 4 installed in the redox reaction vessel 3 does not have to be plate-shaped, and may be a honeycomb structure composed of polygonal chambers as shown in FIG. By forming the honeycomb structure, it becomes easy to increase the area per unit volume of the polymer thin film 4 carrying the semiconductor photocatalyst particles 8 in the redox reaction vessel 3.

【0015】

The optical fiber 5 inserted into the redox container 3 may have a structure in which light leaks from the middle as shown in FIG.

【0016】

[Effect of the invention]

According to the present invention, light can be efficiently introduced into the reaction vessel, and the introduced light can be effectively used for the reaction, so that the redox reaction can be efficiently carried out.

[Simple explanation of drawings]

[Figure 1]

Explanatory drawing of an optical reaction apparatus which shows one Example of this invention.

[Figure 2]

FIG. 3 is a perspective view of a part of a photoreactive cell in another embodiment.

[Fig. 3]

Explanatory drawing of a part of an optical fiber in another embodiment.

[Explanation of symbols]

1 ... Condenser, 2 ... Light Disperser, 3 ... Redox Reaction Device, 4 ... Polymer Thin Film, 5 ... Optical Fiber, 6 ... Injection Port, 7. .Outlet, 8 ... Semiconductor photocatalyst particles.