Photocatalyst modification and organic wastewater degradation integrated device

Abstract

The utility model discloses a photocatalyst modification and organic wastewater degradation integrated device which comprises a preparation container used for preparing a photocatalyst, a three-dimensional displacement platform is arranged in the preparation container, a metal target material is arranged on the three-dimensional displacement platform, and the metal target material is arranged on the preparation container. A laser emitting unit with laser focused on a metal target material is arranged above the preparation container, the preparation container is respectively connected with an automatic deposition collecting unit and a performance evaluation unit through a collecting pump and a sampling pump, the automatic deposition collecting unit is connected with a photocatalytic reactor through a conveying pump, and a catalytic light source is arranged at the top of the photocatalytic reactor. The photocatalytic reactor is respectively connected with the wastewater storage tank and the degradation liquid storage tank through an input pump and an output pump; according to the scheme, the problem that the performance of a product is influenced by parameters when the photocatalyst is modified by pulse laser is solved, the product meeting the preparation target is collected, and the organic wastewater is catalytically degraded and collected, so that the degradation effect of the organic wastewater is conveniently evaluated.

Description

Technical Field

[0001] The utility model relates to the technical field of photocatalyst for wastewater degradation, and particularly relates to an integrated device for photocatalyst modification and organic wastewater degradation. Background Art

[0002] With the development of industrialization and large-scale production activities of human beings, the problem of wastewater needs to be solved urgently. Taking dye wastewater as an example, it contains a large amount of organic matter, heavy metals and toxic components, which pose a serious threat to human life health and ecological environment. Traditional wastewater treatment and degradation methods, such as physical centrifugation, chemical deposition and biological oxidation, are not only insufficient to purify wastewater, but may also introduce secondary pollution. The semiconductor photocatalysis technology can convert light energy into chemical energy. By irradiating the photocatalyst with light of corresponding wavelength, photogenerated electron-hole pairs can be generated and strongly oxidizing hydroxyl radicals can be produced, thus promoting the degradation of wastewater. Moreover, with the development of nanotechnology, photocatalysts at the micro-nano scale have a larger specific surface area and exhibit better catalytic effects. Therefore, photocatalysis using micro-nano semiconductor materials is a green, efficient, economical and environmentally friendly wastewater treatment technology.

[0003] The effect of photocatalysis technology depends on the band gap and electron-hole recombination rate of the photocatalyst used. Taking titanium dioxide (TiO2), the most widely studied semiconductor catalyst material, as an example, it has low cost and no toxicity, excellent photocatalytic activity and stable physical and chemical properties, and is widely used in environmental protection problems such as wastewater treatment. However, titanium dioxide has a wide band gap (such as >3.2 eV) and a high electron-hole recombination rate, and is only sensitive to ultraviolet light, that is, only less than 7% of solar energy can be utilized, which causes a major limitation to the application of titanium dioxide. Noble metal doping is an effective method to improve the photocatalytic performance of titanium dioxide, with unique advantages such as the formation of Schottky barriers and local surface plasmon resonance (LSPR) effects, which can effectively reduce the electron-hole recombination rate and extend the excitation wavelength of titanium dioxide to the visible light range.

[0004] At present, a new, safe and efficient method for modifying micro-nano particle photocatalysts is the pulsed laser ablation in liquid method. Its advantage is that after the reaction optical path is established, only the minimum operation is required to achieve different modification purposes. By replacing the suspension of micro-nano particles to be modified as the liquid phase environment and changing the noble metal target, the required target modification can be realized. The high temperature, high pressure and strong shock wave brought by the pulsed laser can effectively achieve the physical doping of the catalyst to be modified and noble metal nanoparticles, and construct different doping morphologies. Therefore, the PLAL method does not need to purchase additional chemical reagents or precursor molecules, has long-term economic and environmental benefits, and the product does not contain adsorption residues or other functional groups, which is a clean, sustainable and efficient method.

[0005] However, at present, the modification of micro-nano photocatalysts by pulsed laser liquid-phase ablation method has not been industrially promoted. Moreover, during the modification process, it is impossible to monitor and evaluate the performance of the products in real time, as well as the effect of the products on the degradation of wastewater. Summary of the Utility Model

[0006] In view of the above-mentioned deficiencies of the prior art, the present utility model provides an integrated device for photocatalyst modification and organic wastewater degradation, which solves the problem of the influence of parameters on the performance of products during the modification of photocatalysts by pulsed lasers. By adding corresponding control software and processing software, the modification situation is monitored in real time, the products meeting the preparation objectives are collected, and the organic wastewater is catalytically degraded and collected to facilitate the evaluation of its degradation effect.

[0007] To achieve the above object, the technical solution adopted by the present utility model is as follows:

[0008] Provide an integrated device for photocatalyst modification and organic wastewater degradation, which includes a preparation container for preparing photocatalysts. A three-dimensional displacement platform is arranged inside the preparation container, and a metal target is arranged on the three-dimensional displacement platform. A laser emission unit whose laser is focused on the metal target is arranged above the preparation container. The preparation container is connected to a liquid storage container through a liquid supply pump. The preparation container is connected to an automatic deposition collection unit and a performance evaluation unit through a collection pump and a sampling pump respectively. The automatic deposition collection unit is connected to a photocatalytic reactor through a transfer pump. A mixer is arranged inside the photocatalytic reactor, and a catalytic light source is arranged at the top of the photocatalytic reactor. The photocatalytic reactor is connected to a wastewater storage tank and a degradation liquid storage tank through an input pump and an output pump respectively.

[0009] Further, the performance evaluation unit includes an ultraviolet-visible spectrophotometer, a particle size analyzer, a fluorescence spectrometer, and an X-ray diffractometer.

[0010] Further, the catalytic light source is a light source whose wavelength band can be adjusted correspondingly according to the test results of the ultraviolet-visible spectrophotometer.

[0011] Further, the transfer pump, the input pump, and the output pump are flow pumps, and a particle concentration detector is arranged inside the automatic deposition collection unit.

[0012] Further, the photocatalytic reactor is connected to a pH adjustment unit.

[0013] Further, the mixer includes a vertical particle spray pipe, the lower port of the particle spray pipe is close to the bottom of the photocatalytic reactor, and a submersible pump is arranged inside the particle spray pipe.

[0014] Further, the bottom of the photocatalytic reactor is conical.

[0015] The beneficial effects of the present utility model are as follows:

[0016] 1. This solution can collect the products through the automatic deposition and collection unit; test and output various performance indicators of the products through a particle size analyzer, fluorescence spectrometer, and X-ray diffractometer; monitor the absorption spectrum of the micro-nano particle suspension (product) in real time through an ultraviolet-visible spectrophotometer, and adjust the wavelength band of the catalytic light source based on this; control the dosage of the photocatalyst through the cooperation of a flow pump and a particle concentration detector; fully mix and contact the photocatalyst and the organic wastewater through a blender; control and display the pH value of the wastewater in real time through a pH adjustment unit; evaluate the degradation effect by detecting the degradation liquid in the degradation liquid storage tank; thus realizing the quantitative analysis of the photocatalyst performance and the degradation effect.

[0017] 2. The laser emitted by the laser emission unit of this solution is focused on the metal target in the liquid phase environment and irradiated to generate laser plasma. The high temperature and high pressure of the laser plasma and the cavitation bubbles are used to generate micro-nano particles, so that the preparation of the photocatalyst is no longer limited to chemical methods (such as sol-gel method or chemical deposition method), avoiding secondary pollution and residue attachment caused by chemical precursors. At the same time, the metal target can be recycled after polishing treatment. It is convenient, environmentally friendly, cost-saving, and the product performance is excellent. It is a sustainable preparation method.

[0018] 3. The bottom of the photocatalytic reactor of this solution is conical, which is convenient for the photocatalyst particles to deposit at the bottom and be separated from the upper wastewater by stratification; during the wastewater degradation process, the submersible pump can drive the photocatalyst particles at the bottom of the photocatalytic reactor to be sucked in from the lower port of the particle nozzle and ejected from the upper port of the particle nozzle, so that the photocatalyst particles no longer deposit and are fully mixed with the organic wastewater, which is beneficial to improving the degradation effect of the wastewater. Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of an integrated device for photocatalyst modification and organic wastewater degradation.

[0020] Among them, 1. Preparation container, 2. Three-dimensional displacement platform, 3. Metal target, 4. Laser emission unit, 5. Liquid supply pump, 6. Liquid storage container, 7. Collection pump, 8. Sampling pump, 9. Automatic deposition and collection unit, 10. Performance evaluation unit, 11. Delivery pump, 12. Photocatalytic reactor, 13. Catalytic light source, 14. Input pump, 15. Output pump, 16. Wastewater storage tank, 17. Degradation liquid storage tank, 18. Ultraviolet-visible spectrophotometer, 19. Particle size analyzer, 20. Fluorescence spectrometer, 21. X-ray diffractometer, 22. pH adjustment unit, 23. Particle nozzle, 24. Submersible pump. Detailed Implementation Modes

[0021] The specific embodiments of the present utility model will be described below to facilitate those skilled in the art of this technology to understand the present utility model. However, it should be clear that the present utility model is not limited to the scope of the specific embodiments. For those of ordinary skill in the art of this technology, as long as various changes are within the spirit and scope of the present utility model defined and determined by the appended claims, these changes are obvious, and all utility models created using the concept of the present utility model are within the scope of protection.

[0022] As Figure 1 shown, the integrated device for photocatalyst modification and organic wastewater degradation in this solution includes a preparation container 1 for preparing a photocatalyst. A three-dimensional displacement platform 2 is arranged inside the preparation container 1, and a metal target 3 is arranged on the three-dimensional displacement platform 2. The metal target 3 refers to the material for preparing the micro-nano photocatalyst. Above the preparation container 1, there is a laser emission unit 4 whose laser is focused on the metal target 3. The preparation container 1 is connected to a liquid storage container 6 through a liquid supply pump 5. The preparation container 1 is connected to an automatic deposition collection unit 9 and a performance evaluation unit 10 through a collection pump 7 and a sampling pump 8 respectively. The performance evaluation unit 10 includes an ultraviolet-visible spectrophotometer 18, a particle size analyzer 19, a fluorescence spectrometer 20, and an X-ray diffractometer 21.

[0023] The automatic deposition collection unit 9 is connected to a photocatalytic reactor 12 through a transfer pump 11. The photocatalytic reactor 12 is connected to a pH adjustment unit 22. A mixer is arranged inside the photocatalytic reactor 12. At the top of the photocatalytic reactor 12, there is a catalytic light source 13. The catalytic light source 13 is a light source whose wavelength band can be adjusted correspondingly according to the test results of the ultraviolet-visible spectrophotometer 18, such as ultraviolet light, ultraviolet-visible light, etc. The photocatalytic reactor 12 is connected to a wastewater storage tank 16 and a degradation liquid storage tank 17 through an input pump 14 and an output pump 15 respectively. Among them, the transfer pump 11, the input pump 14, and the output pump 15 are flow pumps, and a particle concentration detector is arranged inside the automatic deposition collection unit 9.

[0024] Preferably, the bottom of the photocatalytic reactor 12 is conical, which is convenient for the photocatalyst particles to deposit at the bottom and be separated from the wastewater in the upper part by stratification. The mixer includes a vertical particle spray pipe 23. The lower port of the particle spray pipe 23 is close to the bottom of the photocatalytic reactor 12, and a submersible pump 24 is arranged inside the particle spray pipe 23. Through the submersible pump 24, the photocatalyst particles at the bottom of the photocatalytic reactor 12 can be driven to be sucked in from the lower port of the particle spray pipe 23 and ejected from the upper port of the particle spray pipe 23, so that the photocatalyst particles no longer deposit and are fully mixed with the organic wastewater, which is beneficial to improving the degradation effect of the wastewater.

[0025] The working principle of this solution will be specifically described below:

[0026] Before preparation, the cleaned metal target 3 is placed on the three-dimensional displacement platform 2. Then, liquid is injected into the preparation container 1 through the liquid storage container 6, and the liquid level is 2 - 4 mm above the metal target 3. During the preparation process, the laser energy is monitored in real time, the laser parameters and the movement of the three-dimensional displacement platform 2 are controlled to ensure that the number of single-point actions of the pulsed laser on the target is controllable, so as to improve the preparation efficiency. Moreover, the liquid supply pump 5 keeps working to ensure that the laser action area is timely updated with the photocatalyst suspension to be modified to improve the modification efficiency. When the modified photocatalyst meets the modification target, the product can be collected through the automatic deposition collection unit 9. The performance evaluation unit 10 tests and outputs various performance indicators of the product, including ultraviolet-visible absorption spectrum, particle size, XRD (crystal phase analysis), fluorescence test steady-state spectrum (electron-hole recombination rate analysis), etc. The wavelength band of the catalytic light source 13 is adjusted according to the test results of the ultraviolet-visible spectrophotometer 18. The dosage of the photocatalyst is controlled by the cooperation of the flow pump and the particle concentration detector. The photocatalyst and the organic wastewater can be fully mixed and contacted through the blender. The pH value of the wastewater is controlled and displayed in real time by the pH adjustment unit 22. Thus, the organic wastewater is photocatalytically degraded, and the degradation effect is evaluated by detecting the degradation liquid in the degradation liquid storage tank 17. Therefore, the quantitative analysis of the photocatalyst performance and the degradation effect is realized.

[0027] In specific implementation, a silver plate with a purity greater than 99.99% is used as the metal target 3, and the TiO2 nanoparticle suspension is used as the liquid phase environment to ablate the silver target. The ablation times are 10 minutes, 20 minutes, and 30 minutes respectively. The moving speed of the three-dimensional displacement platform 2 needs to ensure that the time for changing the ablation position is between two pulses of the laser, so as to reduce the influence of the pulse action on the target loss. The organic wastewater to be degraded takes the methylene blue solution at 20 mg / L as an example, and the volume and temperature of the methylene blue solution in each group of experiments are the same.

Claims

1. An integrated device for photocatalyst modification and organic wastewater degradation, characterized in that It includes a preparation container for preparing a photocatalyst. Inside the preparation container, a three-dimensional displacement platform is provided. A metal target is arranged on the three-dimensional displacement platform. Above the preparation container, a laser emission unit whose laser is focused on the metal target is provided. The preparation container is connected to a liquid storage container through a liquid supply pump. The preparation container is connected to an automatic deposition collection unit and a performance evaluation unit through a collection pump and a sampling pump respectively. The automatic deposition collection unit is connected to a photocatalytic reactor through a transfer pump. Inside the photocatalytic reactor, a blender is provided. At the top of the photocatalytic reactor, a catalytic light source is provided. The photocatalytic reactor is connected to a wastewater storage tank and a degradation liquid storage tank through an input pump and an output pump respectively.

2. The integrated device for photocatalyst modification and organic wastewater degradation according to claim 1, wherein The performance evaluation unit includes an ultraviolet-visible spectrophotometer, a particle size analyzer, a fluorescence spectrometer, and an X-ray diffractometer.

3. The integrated device for photocatalyst modification and organic wastewater degradation according to claim 2, characterized in that, The catalytic light source is a light source whose wavelength band can be adjusted correspondingly according to the test results of the ultraviolet-visible spectrophotometer.

4. The integrated device for photocatalyst modification and organic wastewater degradation according to claim 1, wherein The transfer pump, the input pump, and the output pump are flow pumps. A particle concentration detector is arranged inside the automatic deposition collection unit.

5. The integrated device for photocatalyst modification and organic wastewater degradation according to claim 1, characterized in that, The photocatalytic reactor is connected to a pH adjustment unit.

6. The integrated device for photocatalyst modification and organic wastewater degradation according to claim 1, characterized in that, The blender includes a vertical particle spray pipe. The lower port of the particle spray pipe is close to the bottom of the photocatalytic reactor. A submersible pump is arranged inside the particle spray pipe.

7. The integrated device for photocatalyst modification and organic wastewater degradation according to claim 6, characterized in that, The bottom of the photocatalytic reactor is conical.

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