JPH04334552A - Composite photocatalytic material - Google Patents

Abstract

PURPOSE:To provide an impact resisting, continuous large-sized composite photocatalytic material at low costs by heat depositing on a light transmitting fluororesin the light transmitting porous inorg. powder carrying thereon the photocatalyst of metal oxide semiconductor. CONSTITUTION:A desired composite photocatalytic material is obtained by dividing finely light transmitting porous inorg. powder such as quartz and glass carrying thereon the photocatalyst of metal oxide semiconductor such as TiO2, V2O5, ZnO and WO3 or heat depositing on the surface of a light transmitting fluororesin sheet or plate the powder having the photocatalyst of metal oxide semiconductor carried on the previously finely divided light transmitting porous inorg. powder. As the light transmitting fluororesin, perfluoroethylenepropylene resin, perfluoro-alkoxy resin, ethylene-ethylene tetrafluoride resin, etc., are used. The use of this material enhances impact resistance in comparison with the conventional composite photocatalytic material using a quartz glass plate.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a photocatalytic composite material.
For example, the present invention relates to photocatalytic composite materials that are applied to photochemical reaction systems such as denitrification equipment, water treatment equipment, and sterilization and purification equipment.

0002

[Prior Art] Conventionally, TiO2, V2 O5, ZnO, WO3, etc. have been known as metal oxide semiconductor photocatalysts, but industrially, for example, in the case of TiO2,
TiCl4 is diffused and adsorbed onto a light-transmitting porous quartz plate.
After hydrolyzing this with steam, it is fired at 500 to 700°C to support TiO2 and is used as a light-transmitting quartz plate.

0003

Problems to be Solved by the Invention When the above-mentioned conventional light-transmitting quartz plate supporting a metal oxide semiconductor photocatalyst is used industrially, there are the following drawbacks. (1) In order to improve the photochemical reaction efficiency, the thinner the quartz plate is, the better; however, the quartz plate has low impact strength and will collapse even with a slight impact.

(2) In order to prevent the collapse, in order to increase the strength, even though it is not used in the reaction,
It is necessary to make the quartz plate thicker or to reinforce the surrounding area with other materials.

(3) Due to the drawbacks mentioned in (1) and (2) above, it is difficult to manufacture a light-transmitting quartz plate supporting a large-sized metal oxide semiconductor photocatalyst, which is industrially important. The application of this to photochemical reaction processes is also economically problematic.

[0006] In view of the above-mentioned state of the art, the present invention aims to provide a photocatalytic composite material that eliminates the problems of conventional photocatalysts.

[0007]

[Means for Solving the Problems] The present invention is a photocatalytic composite material characterized by thermally welding a light-transmitting porous inorganic powder supporting a metal oxide semiconductor photocatalyst to a light-transmitting fluororesin. be. To describe the present invention more specifically,
The present invention uses metal oxide semiconductor photocatalysts (TiO2, V2
A light-transmissive porous inorganic material (quartz, glass, etc.) supporting O5, ZnO, WO3, etc.) is finely pulverized, or the metal oxide is applied to the light-transmissive porous inorganic material that has been finely ground in advance. The powder supporting the semiconductor photocatalyst is mixed with a light-transmitting fluororesin [perfluoroethylene propylene resin (FEP), perfluoroalkoxy resin (P
FA), ethylene-tetrafluoroethylene resin (ETFE)
It is a photocatalytic composite material that is heated and melted and attached to the surface of a sheet or plate.

[0008]

[Operation] In order to eliminate the drawbacks of conventional photocatalysts, the present invention
The light-transparent porous inorganic material supporting the metal oxide semiconductor photocatalyst has only the function of a photocatalyst, and a light-transparent fluororesin with high impact strength is used as a reinforcing material that requires strength.

[0009] Since the present invention uses a light-transmissive porous inorganic powder supporting a metal oxide semiconductor photocatalyst, more active sites effective for photochemical reactions can be utilized than in the case of a conventional plate material supporting the photocatalyst. Because it uses a fluororesin film or sheet that has the advantages and high transmittance of ultraviolet rays,
It also has low attenuation of light energy and high energy efficiency.

0010

Embodiments Hereinafter, embodiments of the present invention will be explained with reference to FIGS. 1 and 2. Figure 1 shows a porous quartz glass powder 1 supporting a TiO2 photocatalyst with an average particle size of 10 μm as a metal oxide semiconductor photocatalyst, and a 100 μm fluororesin film 2.
FIG. 2 is a cross-sectional view showing an embodiment of the present invention heat-sealed to. FIG. 2 is a cross-sectional view of a 100 μm fluororesin film 2 and a porous quartz glass powder 1 carrying a TiO2 photocatalyst with an average particle size of 10 μm, which is thermally fused on both sides.

The porous quartz glass powder 1 supporting the TiO2-based photocatalyst of the photocatalytic composite material of the present invention shown in FIGS. 1 and 2 is prepared by adsorbing TiCl4 onto a porous quartz glass plate, and then hydrolyzing it at 180°C. The material was fired at 600°C and ground to 10 μm.

[0012] Powder 1 prepared by the above method was 350 to 40
100μm FEP film, PFA film heated to 0℃ and heated to a temperature 50 to 100℃ lower than the melting point,
After spraying on ETFE film, it is compressed with a roll and T
Porous quartz glass powder 1 supporting iO2 was thermally fused to the surface of a fluororesin film 2, thereby creating a fluororesin composite material to which a TiO2 photocatalyst was thermally fused.

[0013] The fluororesin composite material prepared by the above method and heat-sealed with TiO2 photocatalyst has a length of 280 mm and a width of 3
A 0 mm sheet was set in a photochemical reaction vessel (length 280 mm x width 30 mm x height 20 mm) equipped with a low-pressure Hg lamp, and a gas containing 470 ppm of He and NO mixed at 20 °C was passed through at a rate of 100 ml/min. NO
A reduction reaction was performed. The result is 100μm TiO2
The reaction rate and energy efficiency were almost the same as in a test conducted using a porous quartz glass plate supporting a photocatalyst.

[0014]

[Effect of the invention] The present invention uses a light-transmitting fluororesin that is flexible and strong against impact as a base material, and is a continuous large composite material that does not easily collapse like conventional quartz glass plates. can also be manufactured cheaply. Furthermore, depending on the shape of the reactor, it can be changed to any shape, which has great industrial value.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an example of the photocatalytic composite material of the present invention.

FIG. 2 is a sectional view of another example of the photocatalytic composite material of the present invention.

Claims (1)

[Claims] 1. A photocatalytic composite material comprising a light-transparent porous inorganic powder supporting a metal oxide semiconductor photocatalyst and heat-welded to a light-transparent fluororesin.