Photocatalyst activity evaluation device

Abstract

The utility model provides a device for evaluating the activity of a photocatalyst. The device comprises a constant-temperature circulating water bath kettle and a photocatalytic reaction box, a photocatalytic reactor and a light source are arranged in the photocatalytic reaction box; the light source is arranged above the photocatalytic reactor; a water inlet and a water outlet are formed in the lower end of the photocatalytic reactor; a first piston opening and a second piston opening are formed in the upper end of the photocatalytic reactor; a sample inlet is formed in the side wall of the photocatalytic reactor; and a sealing cover is arranged at the top end of the photocatalytic reactor. The photocatalytic reactor provided by the utility model has the advantages of small volume, small catalyst dosage, constant-temperature control, stable illumination intensity and uniform gas mixing, and can be used for effectively evaluating the activity of the photocatalyst.

Description

Technical Field

[0001] The invention belongs to the technical field of photocatalytic devices, and in particular relates to a photocatalyst activity evaluation device. Background Art

[0002] With the development of environmental protection and energy utilization technology, photocatalytic technology has attracted much attention due to its important applications in environmental pollution control and clean energy generation. Formaldehyde is a colorless, toxic organic substance. Long-term living in an environment with excessive formaldehyde will cause many diseases. Therefore, it is of great significance to find a method that can effectively remove indoor formaldehyde. However, the activity evaluation of photocatalysts is a key step in the research and development process. At present, the activity evaluation device of the catalyst for photocatalytic degradation of formaldehyde gas is mostly composed of a photocatalytic reactor, a gas chromatograph or a gas detector. In this device, the photocatalytic reactor is directly connected to the gas detector to continuously monitor the formaldehyde concentration, and finally obtain the formaldehyde concentration reduction under a certain period of time to evaluate the photocatalytic activity of the catalyst. The advantage of this device is that it can monitor the amount of formaldehyde in the photocatalytic degradation gas more accurately and sensitively. Its disadvantages are: it is difficult to control the temperature and humidity in the photocatalytic reactor, the catalyst dosage is large, and the price is expensive.

[0003] For the above reasons, many researchers are limited by experimental conditions and cannot carry out research on photocatalytic degradation of formaldehyde gas. Based on the current status and actual needs, it is of great practical significance to design a photocatalyst activity evaluation device that can accurately control reaction conditions, has good sealing and a stable light source. Utility Model Content

[0004] The utility model provides a photocatalyst activity evaluation device, which solves the problems of difficulty in controlling temperature and humidity in an existing photocatalytic reactor, large catalyst usage and high price.

[0005] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0006] A device for evaluating the activity of a photocatalyst comprises a constant temperature circulating water bath and a photocatalytic reaction box; a photocatalytic reactor and a light source are arranged inside the photocatalytic reaction box; the light source is arranged above the photocatalytic reactor; a water inlet and a water outlet are arranged at the lower end of the photocatalytic reactor; a first piston port and a second piston port are arranged at the upper end of the photocatalytic reactor; a sample inlet is arranged on the side wall of the photocatalytic reactor; and a sealing cover is arranged at the top of the photocatalytic reactor.

[0007] Furthermore, the water inlet and the water outlet are both connected to the constant temperature circulating water bath through rubber tubes.

[0008] Furthermore, the first piston port and the second piston port are both sealed by vacuum grease and fixed by rubber bands.

[0009] Furthermore, the sealing cover is a quartz glass cover.

[0010] Furthermore, the quartz glass cover is fixedly connected by a fixing clip.

[0011] Furthermore, the number of the fixing clips is 2-5.

[0012] Furthermore, the light source is a xenon lamp.

[0013] Furthermore, a fan is provided in the photocatalytic reaction box.

[0014] Furthermore, a sample holder is provided in the photocatalytic reactor.

[0015] Compared with the prior art, the advantages and beneficial effects of the utility model are:

[0016] 1. The photocatalytic reactor of the utility model device is small in size, simple in operation, easy to use, and uses a small amount of catalyst. There is no need to purchase expensive gas chromatographs, gas detectors and samplers, and no need to use standard gas;

[0017] 2. The device of the utility model has good air tightness, can stabilize the initial concentration of the gas in the device, and has a good effect on the evaluation of photocatalyst activity;

[0018] 3. The device of the utility model can achieve constant temperature control, stable light intensity, uniform gas mixing, and can effectively evaluate the activity of photocatalysts. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Fig. 1 is a schematic diagram of the structure of the utility model device;

[0020] Figure numerals: 1. first piston port; 2. second piston port; 3. injection port; 4. sealing cover; 5. fixing clamp; 6 light source; 7. water inlet; 8. water outlet; 9. constant temperature circulating water bath; 10. fan; 11. photocatalytic reaction box; 12. photocatalytic reactor. DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods, but the scope of protection required by the present invention is not limited to the scope described in the examples. Example 1

[0022] Combined with Figure 1 As shown, the utility model provides a photocatalyst activity evaluation device, which includes a constant temperature circulating water bath 9 and a photocatalytic reaction box 11; a photocatalytic reactor 12 and a light source 6 are arranged inside the photocatalytic reaction box 11; the light source 6 is a xenon lamp, which is provided with a filter inside, and the switch of the xenon lamp is controlled by a light source controller.

[0023] The photocatalytic reactor 12 is provided with a water inlet 7 and a water outlet 8 at the lower end; the water inlet 7 and the water outlet 8 are both connected to a constant temperature circulating water bath pot through a rubber tube to achieve a constant temperature water bath.

[0024] The upper end of the photocatalytic reactor 12 is provided with a first piston port 1 and a second piston port 2; the first piston port 1 and the second piston port 2 are both sealed by vacuum grease and fastened by rubber bands to ensure the airtightness of the reactor.

[0025] A sealing cover 4 is provided at the top of the photocatalytic reactor 12 and is fixedly connected by 2-5 fixing clips 5. The sealing cover 4 is a quartz glass cover, which is conducive to full contact between visible light and materials.

[0026] By sealing the first piston port 1 and the second piston port 2 and the sealing cover 4 of the photocatalytic reactor 12, good air tightness can be achieved to ensure that the initial concentration of formaldehyde can be kept constant.

[0027] The light source 6 is placed above the sealing cover 4 at a constant distance to perform a photocatalytic reaction, thereby achieving effective removal of formaldehyde at a low cost.

[0028] The side wall of the photocatalytic reactor 12 is provided with a sample inlet 3 for introducing gas samples and absorbents.

[0029] The photocatalytic reactor 12 includes a sample holder for loading and fixing the photocatalyst. Since the sample holder is small in size, the amount of photocatalyst used can be reduced.

[0030] The photocatalytic reaction box 11 is further provided with a fan 10 for enhancing air circulation in the photocatalytic reaction box and improving reaction efficiency. Example 2

[0031] When using the device of the utility model to test the catalyst activity of photocatalytic degradation of formaldehyde gas, first, the constant temperature circulating water bath 9 maintains a stable temperature environment during the photocatalytic reaction, the sealing cover 4 and the piston port are tightly connected, and a certain amount of formaldehyde liquid is transferred through the injection port 3 into the photocatalytic reactor 12 by a micro-syringe to make it naturally volatilize into gas, and then the light source is started, wherein the test sample is placed on the sample holder.

[0032] When measuring formaldehyde, firstly, a certain amount of distilled water is pipetted and slowly injected from the injection port 3 of the reactor through a syringe, and the aqueous solution is taken out after absorbing formaldehyde for a certain period of time. After cooling, a certain volume of formaldehyde liquid and acetylacetone solution are pipetted and mixed, and heated in a water bath at a certain temperature for a period of time, and then taken out, and diluted and fixed to volume after cooling, and the absorbance is measured with a UV spectrophotometer. Finally, the formaldehyde degradation rate is calculated according to the following formula:

[0033] ,

[0034] in, D is the degradation rate of formaldehyde; A 0 is the initial absorbance of formaldehyde; A It is the absorbance of formaldehyde after a certain period of illumination.

[0035] In summary, the above-mentioned implementation modes are not limitative implementation modes of the present invention, and any modification or equivalent deformation made by technicians in this field on the basis of the essential content of the present invention is within the technical scope of the present invention.

Claims

1. A device for evaluating photocatalytic activity, characterized in that It comprises a constant temperature circulating water bath and a photocatalytic reaction box; a photocatalytic reactor and a light source are arranged inside the photocatalytic reaction box; the light source is arranged above the photocatalytic reactor; a water inlet and a water outlet are arranged at the lower end of the photocatalytic reactor; a first piston port and a second piston port are arranged at the upper end of the photocatalytic reactor; a sample inlet is arranged on the side wall of the photocatalytic reactor; and a sealing cover is arranged at the top of the photocatalytic reactor.

2. A photocatalyst activity evaluation device according to claim 1, characterized in that: The water inlet and the water outlet are both connected to the constant temperature circulating water bath pot through rubber tubes.

3. A photocatalyst activity evaluation device according to claim 1 or 2, characterized in that: The first piston port and the second piston port are both sealed by vacuum grease and fixed by rubber bands.

4. A photocatalyst activity evaluation device according to claim 3, characterized in that: The sealing cover is a quartz glass cover.

5. A photocatalyst activity evaluation device according to claim 4, characterized in that: The quartz glass cover is fixedly connected by a fixing clip.

6. A photocatalyst activity evaluation device according to claim 5, characterized in that: The fixing clips include 2-5 pieces.

7. A photocatalyst activity evaluation device according to claim 1, characterized in that: The light source is a xenon lamp.

8. A photocatalyst activity evaluation device according to claim 1, characterized in that: A fan is arranged in the photocatalytic reaction box.

9. A photocatalyst activity evaluation device according to claim 1, characterized in that: A sample holder is arranged in the photocatalytic reactor.

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