Method for efficiently degrading dye in water based on vacuum ultraviolet rays

Abstract

The invention belongs to the technical field of water treatment, and particularly relates to a method for efficiently degrading dye in water based on vacuum ultraviolet rays, which comprises the following steps: adding a dye-containing sample water body into a sample container of a photoreaction device, and starting a magnetic stirrer to uniformly mix liquid in the sample container under the action of rapid rotation of a magnetic stirring rotor; adding a persulfate reagent into the sample container to obtain a reaction solution; opening the peristaltic pump, pumping the reaction solution in the sample container into the high-purity quartz annular reaction layer under the action of the peristaltic pump, and reacting under the irradiation of vacuum ultraviolet rays to degrade the dye in the reaction solution.

Description

Technical Field

[0001] The present application belongs to the technical field of water treatment, and specifically relates to a method for efficiently degrading dyes in water based on vacuum ultraviolet rays. Background Art

[0002] Many dye molecules are toxic and may have adverse effects on aquatic organisms. In addition, drinking water contaminated by dyes contains carcinogenic byproducts, which poses a potential risk to human health. In addition, the persistence and bioaccumulation of dyes may also lead to imbalances in aquatic ecosystems. Many dyes are difficult to degrade and remain in the water environment for a long time, causing persistent pollution to the environment.

[0003] Therefore, effectively removing dye pollutants from water bodies is not only a need to improve water quality, but also an important measure to maintain the ecological environment and human health. Traditional water treatment technologies, such as adsorption, sedimentation, coagulation-flocculation and sand filtration, are difficult to effectively remove dyes with greater toxic effects. The presence of various dyes in water bodies not only poses potential health risks to the human body, but also causes certain damage to the ecosystem. At present, traditional water treatment technologies generally have the disadvantages of low efficiency and high cost in degrading dyes in water bodies. Summary of the invention

[0004] The present application provides a method for efficiently degrading dyes in water based on vacuum ultraviolet rays, which can solve the problems of low degradation efficiency and high degradation cost of dyes in water in the prior art.

[0005] The present application provides a method for efficiently degrading dyes in water based on vacuum ultraviolet light, comprising:

[0006] Add the sample water containing the dye into the sample container of the photoreaction device, turn on the magnetic stirrer, and make the liquid in the sample container evenly mixed under the action of the rapid rotation of the magnetic stirring rotor;

[0007] adding a persulfate (PS) reagent into a sample container to obtain a reaction solution;

[0008] The peristaltic pump is turned on, and the reaction solution in the sample container is pumped into the high-purity quartz annular reaction layer under the action of the peristaltic pump, and reacts under the irradiation of vacuum ultraviolet light (VUV) to degrade the dye in the reaction solution;

[0009] The photoreaction device comprises: a photoreactor, a liquid circulation system and a constant temperature water bath layer; the photoreactor comprises: a detachable light source and a high-purity quartz annular reaction layer, the detachable light source is vertically arranged in the photoreactor, and the detachable light source is used to generate VUV; a constant temperature water bath layer is sleeved on the outer side of the photoreactor; the liquid circulation system comprises: a magnetic stirrer, a liquid outlet pipe, a liquid return pipe and a sample container, one end of the liquid outlet pipe is connected to the sample container, the other end of the liquid outlet pipe is detachably connected to the high-purity quartz annular reaction layer, one end of the liquid return pipe is connected to the sample container, and the other end of the liquid return pipe is detachably connected to the high-purity quartz annular reaction layer; the magnetic stirrer is used to place the sample container, a magnetic stirring rotor is placed in the sample container, and a peristaltic pump is connected to the middle part of the liquid outlet pipe.

[0010] Optionally, reacting under VUV irradiation to degrade the dye in the reaction solution comprises:

[0011] The water molecules in the reaction solution are decomposed by VUV light to produce HO ● , HO ● Used to degrade dyes in reaction solutions.

[0012] Optionally, reacting under VUV irradiation to degrade the dye in the reaction solution comprises:

[0013] The PS in the reaction solution was decomposed by VUV photolysis to generate reactive oxygen species (ROSs), which were used to degrade the dye in the reaction solution.

[0014] Optionally, ROSs, including:

[0015] HO ● HO2 ● 、O2 ●- 、SO4 ●- 、SO5 ●- and S2O8 ●- .

[0016] Alternatively, the pH of the reaction solution is adjusted with different phosphate solutions so that the total concentration of phosphate species is 2.0 mM.

[0017] Optionally, the phosphate solution includes: H3PO4, NaH2PO4, Na2HPO4 and Na3PO4;

[0018] Phosphate species, including: PO4 3- 、HPO4 2- 、H2PO 4- and H3PO4.

[0019] Optionally, under the VUV irradiation emitted by the photoreaction device, PS in the reaction solution is cracked to generate SO4 ●- and HO● , used to degrade the dye in the reaction solution.

[0020] Optionally, the dye is methylene blue (MB).

[0021] Optionally, before adding the sample water containing the dye into the sample container of the photoreaction device, the method further comprises:

[0022] Install the VUV lamp to the photoreaction device; the detachable light source is the VUV lamp;

[0023] Turn on the cooling circulator, pump ultrapure water into the constant temperature water bath through the cooling water inlet and discharge it back through the cooling water outlet;

[0024] Turn on the VUV lamp of the photoreaction device to preheat the irradiation chamber;

[0025] Open the high-purity N2 gas cylinder, and continuously pass high-purity N2 into the irradiation chamber through the high-purity N2 inlet and discharge it from the high-purity N2 exhaust port, so that the irradiation chamber is filled with high-purity N2.

[0026] Optionally, the method further comprises:

[0027] After the reaction is completed, the solution in the high-purity quartz annular reaction layer is drained, and ultrapure water is injected to thoroughly clean the inlet and outlet connecting hoses and the inner wall of the high-purity quartz annular reaction layer. After cleaning, the water in the connecting hose and the high-purity quartz annular reaction layer is drained and the peristaltic pump is stopped.

[0028] In the embodiment of the present application, a sample water body containing a dye is added to a sample container of a photoreaction device, and a magnetic stirrer is turned on so that the liquid in the sample container is evenly mixed under the action of the rapid rotation of the magnetic stirring rotor; a PS reagent is added to the sample container to obtain a reaction solution; a peristaltic pump is turned on, and the reaction solution in the sample container is pumped into a high-purity quartz annular reaction layer under the action of the peristaltic pump, and reacts under the irradiation of VUV. On the one hand, the irradiation of the reaction solution by VUV can photolyze the water molecules in the reaction solution to produce a large amount of strongly oxidizing HO ● On the other hand, VUV can accelerate the cleavage of PS and generate a large amount of ROSs to degrade the dye in the reaction solution. Thus, the degradation efficiency of the dye in the water can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic structural diagram of a photoreaction device provided in an embodiment of the present application;

[0030] Figure 2 This is a MB morphology distribution diagram provided in an embodiment of the present application;

[0031] Figure 3This is a schematic diagram of the degradation rate of a dye in water provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail in conjunction with the embodiments below. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0033] In order to facilitate the explanation of the method provided by the present application for efficiently degrading dyes in water based on vacuum ultraviolet rays, the photoreaction device used in the method of the present application is described below:

[0034] like Figure 1 As shown, this embodiment provides a light reaction device, including:

[0035] Photoreactor 10, liquid circulation system 20 and constant temperature water bath layer 30;

[0036] The photoreactor 10 includes: a detachable light source 11, a high-purity quartz annular reaction layer 12, a top cover 13, and a bottom cover 14;

[0037] A top cover 13 and a bottom cover 14 are respectively disposed at the top and bottom of the photoreactor 10, and a detachable light source 11 is vertically disposed inside the photoreactor; the detachable light source 11 is detachably fixed to the top cover 13;

[0038] The outer side of the photoreactor is provided with a constant temperature water bath layer 30;

[0039] The liquid circulation system 20 includes: a liquid outlet pipe 21, a liquid return pipe 22 and a sample container 23. One end of the liquid outlet pipe 21 is connected to the sample container 23, and the other end of the liquid outlet pipe 21 is detachably connected to the high-purity quartz annular reaction layer 12. One end of the liquid return pipe 22 is connected to the sample container 23, and the other end of the liquid return pipe 22 is detachably connected to the high-purity quartz annular reaction layer 12.

[0040] The detachable light source 11 refers to a light source inside the photoreactor that can be easily disassembled and replaced, such as a UV lamp or a light-emitting diode lamp, etc., which is convenient for maintenance and optimization of the light source and improves the flexibility and adaptability of the system.

[0041] The high-purity quartz annular reaction layer 12 is the main reaction area for placing photocatalysts or samples inside the photoreactor 10. The light emitted by the detachable light source 11 irradiates the high-purity quartz annular reaction layer 12 to stimulate the photocatalytic reaction or directly act on the sample.

[0042] In the embodiment of the present application, on the one hand, the high-purity quartz annular reaction layer 12 can make the structure of the entire photoreaction device more compact and stable, which can not only reduce the volume of the photoreaction device, but also facilitate the transportation of the device and extend the service life of the photoreaction device.

[0043] On the other hand, compared with traditional high-purity quartz capillary tubes, the volume of the high-purity quartz annular reaction layer is significantly larger, which can increase the irradiation area of ​​the light source and the utilization efficiency of photons, reduce the cost of sewage treatment, and improve the efficiency of sewage treatment.

[0044] In addition, the high-purity quartz annular reaction layer can increase the amount of wastewater treated in a single test, so that each sampling in the detection process has little or even negligible impact on the total volume of the reaction solution, ensuring the scientificity and accuracy of the experimental results.

[0045] Furthermore, the high-purity quartz annular reaction layer can significantly increase the amount of wastewater treated per unit time, laying a good foundation for the practical promotion and application of related water treatment technologies in the future.

[0046] The top cover and bottom cover refer to the closed covers at the upper and lower ends of the photoreactor, which play the role of sealing the internal environment of the reactor and controlling the temperature and other conditions.

[0047] The detachable light source and the top cover body are detachably fixed, which means that the light source, reaction layer and other components are detachably connected to the cover body, so that it is easy to open the photoreactor to perform operations such as light source maintenance.

[0048] In the embodiments of the present application, the high-purity quartz annular reaction layer has a stable structure, and can easily realize the switching and updating of different detachable light sources. By comparing the treatment effects of pollutants under different light sources, the mechanism can be explored.

[0049] The constant temperature water bath layer is a temperature-controlled water bath system arranged outside the photoreactor. Through the constant temperature water bath layer, the temperature conditions inside the reactor can be accurately controlled.

[0050] The liquid circulation system is a circulating flow system composed of a liquid outlet pipe, a liquid return pipe and a sample container, which can realize the continuous circulation of the reaction liquid between the reaction layer and the collection container, thereby improving the throughput of sample processing.

[0051] A high-purity nitrogen inlet pipe 15 and a high-purity nitrogen exhaust pipe 16 are respectively arranged on the photoreactor. The high-purity nitrogen inlet pipe 15 is connected to a high-purity nitrogen bottle, and the high-purity nitrogen exhaust pipe 16 is connected to the outside air.

[0052] The high-purity nitrogen gas inlet pipe 15 is connected to the high-purity nitrogen gas bottle, and high-purity nitrogen gas can be introduced into the interior of the photoreactor through the high-purity nitrogen gas inlet pipe 15.

[0053] The high-purity nitrogen exhaust pipe 16 is connected to the outside air. Through the high-purity nitrogen exhaust pipe 16, the gas inside the photoreactor can be discharged into the outside air.

[0054] By continuously supplying high-purity nitrogen into the reactor, active gases such as oxygen in the air can be removed, providing a stable reaction environment and supporting the reaction process.

[0055] The middle part of the liquid outlet pipe is connected with a peristaltic pump 24, and the flow rate of the peristaltic pump is 600-1200mL / min.

[0056] The peristaltic pump 24 can accurately control the flow rate of the liquid outlet to meet the liquid delivery requirements during the reaction process. The working principle of the peristaltic pump 24 is to produce a continuous, pulsation-free delivery effect by squeezing the hose through the roller, which can maintain the stable flow of the liquid in the liquid outlet pipe and avoid fluctuations in the flow rate, which is conducive to the smooth progress of the reaction process.

[0057] When the pressure in the reactor changes, the peristaltic pump 24 can prevent the liquid from flowing back into the reactor, thereby ensuring the stability of the reaction process. As an intermediate component of the liquid outlet pipe 21, the peristaltic pump 24 can be easily maintained and replaced, thereby improving the reliability of the entire system.

[0058] Wherein, the liquid circulation system 20 further includes:

[0059] The magnetic stirrer 25 is used to place the sample container 23 , and a magnetic stirring rotor is placed in the sample container 23 .

[0060] The magnetic stirrer 25 generates a controllable magnetic field to drive the magnetic stirring rotor inside the container to rotate, thereby achieving continuous stirring of the substances inside the sample container and increasing the contact and mixing between the reactants.

[0061] The sample container 23 is used to hold the raw materials or reactants that need to undergo photoreaction, and a magnetic stirring rotor is placed inside the container 23. When the magnetic stirring rotor is placed inside the sample container, it will rotate under the action of the external magnetic stirrer, thereby driving the reactants inside the container to mix.

[0062] Among them, a water outlet and a water inlet are respectively arranged at the top and bottom of the constant temperature water bath layer. The water outlet of the constant temperature water bath layer is connected to the water inlet of the cooling circulator through an outlet pipe, and the water outlet of the cooling circulator is connected to the water inlet of the constant temperature water bath layer through an inlet pipe.

[0063] The constant temperature water bath layer can maintain a constant temperature inside the water bath layer through continuous water inlet and outlet, providing a stable temperature environment for the photoreaction process. The outlet pipe and the inlet pipe form a closed circulating water circuit, connecting the constant temperature water bath layer with the cooling circulator. The cooling circulator can control the temperature of the circulating water and feed it back to the constant temperature water bath layer to maintain a constant temperature condition inside the photoreactor.

[0064] The coordinated work of the constant temperature water bath layer, circulation pipeline and cooling circulator provides precise temperature control for the photoreaction process, ensuring that the reaction can proceed at the optimal temperature.

[0065] The following is a description of a method for efficiently degrading dyes in water based on vacuum ultraviolet light provided in this application:

[0066] First, prepare the experimental materials:

[0067] All chemicals were of reagent grade or above and were not further purified before use. All solutions were prepared with ultrapure water (resistivity>18.2MΩcm). The chemical structure of MB is shown below:

[0068]

[0069] The chemical formula is C 16 H 18 ClN3S, molecular weight is 319.85, and the morphological distribution of MB is shown in 2.

[0070] Experimental preparation stage:

[0071] Step 110, installing a VUV lamp to the photoreaction device; the detachable light source is a VUV lamp;

[0072] Step 120, turn on the cooling circulator, pump ultrapure water into the constant temperature water bath layer through the cooling water inlet and discharge it from the cooling water outlet for reflux;

[0073] Step 130, turning on the VUV lamp of the photoreaction device to preheat the irradiation chamber;

[0074] Step 140, open the high-purity N2 gas cylinder, continuously pass the high-purity N2 into the irradiation chamber through the high-purity N2 gas inlet and discharge it from the high-purity N2 exhaust port, so that the irradiation chamber is filled with high-purity N2.

[0075] Optionally, the water temperature of the thermostatic water bath is kept constant at 25°C.

[0076] Optionally, the preheating time is more than 30 minutes.

[0077] Involving the formal experimental stage:

[0078] Step 210, adding the sample water containing the dye into the sample container of the photoreaction device, turning on the magnetic stirrer, so that the liquid in the sample container is evenly mixed under the action of the rapid rotation of the magnetic stirring rotor;

[0079] Optionally, the dye is MB.

[0080] MB is a common organic dye that can undergo reversible redox reactions.

[0081] Step 220, adding PS reagent into the sample container to obtain a reaction solution;

[0082] PS has a good degradation effect on various organic pollutants such as pesticides, dyes, pharmaceutical residues, industrial chemicals, etc. The active species generated after PS activation, such as HO ● and SO4 ●- , which can efficiently oxidize and decompose these organic compounds.

[0083] Alternatively, the pH of the reaction solution is adjusted with different phosphate solutions so that the total concentration of phosphate species is 2.0 mM.

[0084] To achieve a total phosphate concentration of 2.0 mM, the concentrations of the various phosphate components can be calculated based on the desired pH. For example, if pH 7.0 is desired, a solution of 1.0 mM NaH2PO4 and 1.0 mM Na2HPO4 can be prepared. The reaction solution and phosphate buffer are mixed in a certain ratio. The pH of the final solution can be adjusted, either by titration or by continuous addition of buffer, stepwise to adjust the solution pH to the target value.

[0085] Optionally, the phosphate solution includes: H3PO4, NaH2PO4, Na2HPO4 and Na3PO4;

[0086] Phosphate species, including: PO4 3- 、HPO4 2- 、H2PO 4- and H3PO4.

[0087] Step 230, turning on the peristaltic pump, the reaction solution in the sample container is pumped into the high-purity quartz annular reaction layer under the action of the peristaltic pump, and reacts under the irradiation of VUV to degrade the dye in the reaction solution.

[0088] VUV / UV is an advanced oxidation technology that uses VUV or UV irradiation to produce strong oxidizing species, thereby achieving efficient degradation of organic pollutants.

[0089] The wavelength range of VUV light is usually 100-200nm, and its photon energy is high enough to split water molecules to produce highly oxidizing HO ●.

[0090] H2O+hv→HO ● +H ●

[0091] Optionally, a reaction is carried out under VUV irradiation to degrade the dye in the reaction solution, including: photolysis of water molecules in the reaction solution by VUV to generate HO ● , HO ● Used to degrade dyes in reaction solutions.

[0092] A large amount of HO can be generated in a short time ● In a high concentration water environment (about 55.6M), VUV irradiation can still efficiently photolyze water molecules. HO generated by VUV photolysis of water molecules ● It is a highly reactive strong oxidant. ● It can oxidize and decompose dyes quickly and efficiently.

[0093] The rate of VUV photolysis of water molecules is much higher than that of traditional UV light photolysis of water. The VUV / UV / PS process can produce a large amount of HO in a short time. ● , thereby greatly improving processing efficiency.

[0094] Optionally, a reaction occurs under VUV irradiation to degrade the dye in the reaction solution, including: photolyzing PS in the reaction solution by VUV to generate ROSs, and the ROSs are used to degrade the dye in the reaction solution.

[0095] ROS has strong oxidative ability and can decompose organic pollutants more efficiently.

[0096] VUV light (wavelength range of 100-200nm) has high photon energy, which can effectively excite PS molecules and promote their cleavage. Under VUV light, PS will undergo a faster cleavage reaction:

[0097] S2O8 2- +hv→2SO4 ●-

[0098] Can greatly increase SO4 ●- The rate of production of SO4 ●- It is a strong oxidant in itself. These free radicals will further cause a chain reaction to produce HO ● And other ROSs.

[0099] VUV light accelerates the cracking of PS and speeds up the entire oxidation reaction. Compared with traditional UV / PS technology, VUV / UV / PS can significantly improve processing efficiency and speed.

[0100] Optionally, ROSs, including:

[0101] HO ● HO2 ● 、O2 ●- 、SO4 ●- 、SO5 ●- and S2O8 ●- .

[0102] Optionally, the method further comprises:

[0103] After the reaction is completed, the solution in the high-purity quartz annular reaction layer is drained, and ultrapure water is injected to thoroughly clean the inlet and outlet connecting hoses and the inner wall of the high-purity quartz annular reaction layer. After cleaning, the water in the connecting hose and the high-purity quartz annular reaction layer is drained and the peristaltic pump is stopped.

[0104] The manufacturing and maintenance costs of VUV / UV lamps are similar to those of traditional low-pressure mercury lamps, so without increasing costs, VUV / UV / PS technology can generate more high redox potential, strong oxidizing HO in situ. ● and SO4 ●- , thereby accelerating the removal of difficult-to-degrade organic pollutants in water bodies.

[0105] VUV / UV / PS technology can also avoid some common shortcomings of other advanced oxidation technologies:

[0106] VUV / UV / PS technology does not require the addition of metal catalysts such as iron ions, so it will not produce difficult-to-treat iron sludge precipitation.

[0107] VUV / UV / PS technology does not require the use of fixed catalysts, so there is no problem of catalyst separation and regeneration.

[0108] The VUV / UV / PS process mostly uses direct irradiation and does not require membrane separation, thus avoiding the problem of membrane contamination.

[0109] VUV / UV / PS only requires energy for irradiation. Compared with technologies using iron ions or other catalysts, it does not require large amounts of chemical reagents and has a lower overall processing cost.

[0110] In addition, VUV / UV / PS is a clean and efficient advanced oxidation technology that is simple to operate, easy to automate and control, and has a good degradation effect on a variety of organic pollutants. It can be combined with other technologies to further improve treatment efficiency.

[0111] Combine the following Figure 3The experimental results are explained as follows: the degradation of MB in the five treatment technologies (UV, VUV / UV, PS, UV / PS and VUV / UV / PS technologies) all conform to the pseudo-first-order reaction kinetics, and the fitting coefficient (R 2 ) are all greater than 0.90, where k represents the degradation rate constant. PS itself is a strong oxidant and MB has a large molar absorption coefficient at 254 nm, but only a small amount of MB can be directly oxidized by PS or directly photolyzed by UV (k UV =6.8m 2 / einstein). After 10 min of reaction, the degradation rates of MB under PS and UV technology were both less than 10%.

[0112] UV / PS technology can significantly increase the degradation rate of MB (k UV / PS =78m 2 / einstein), the degradation rate reached 53% after 10 minutes of reaction, which is because more SO4 was generated in the reaction system ●- and HO ● .

[0113] In low concentration MB (10 μM) solution, high concentration H2O can generate a large amount of strong oxidizing HO under VUV / UV irradiation. ● , thereby achieving rapid degradation of MB (k VUV / UV =251m 2 / einstein), 90% of MB was degraded within 10 min.

[0114] In addition, since VUV and UV can photolyze PS to generate additional SO4 ●- Therefore, the degradation of MB in VUV / UV / PS technology (k VUV / UV / PS =328m 2 / einstein) is significantly faster than VUV / UV technology. Compared with UV / PS technology, the additional VUV can photolyze H2O and PS to generate more ROSs, which ultimately makes k VUV / UV / PS Reach k UV / PS 4 times of that.

[0115] In the embodiment of the present application, a sample water body containing a dye is added to a sample container of a photoreaction device, and a magnetic stirrer is turned on so that the liquid in the sample container is evenly mixed under the action of the rapid rotation of the magnetic stirring rotor; a PS reagent is added to the sample container to obtain a reaction solution; a peristaltic pump is turned on, and the reaction solution in the sample container is pumped into a high-purity quartz annular reaction layer under the action of the peristaltic pump, and reacts under the irradiation of VUV. On the one hand, the irradiation of the reaction solution by VUV can photolyze the water molecules in the reaction solution to produce a large amount of strongly oxidizing HO ●On the other hand, VUV can accelerate the cleavage of PS and generate a large amount of ROSs to degrade the dye in the reaction solution. Thus, the degradation efficiency of the dye in the water can be improved.

Claims

1. A method for efficiently degrading dyes in water based on vacuum ultraviolet light, characterized in that: include: Add the sample water containing the dye into the sample container of the photoreaction device, turn on the magnetic stirrer, and make the liquid in the sample container evenly mixed under the action of the rapid rotation of the magnetic stirring rotor; adding a persulfate PS reagent into a sample container to obtain a reaction solution; Turn on the peristaltic pump, and the reaction solution in the sample container is pumped into the high-purity quartz annular reaction layer under the action of the peristaltic pump, and reacts under the irradiation of vacuum ultraviolet light VUV to degrade the dye in the reaction solution; The photoreaction device comprises: a photoreactor, a liquid circulation system and a constant temperature water bath layer; the photoreactor comprises: a detachable light source and a high-purity quartz annular reaction layer, the detachable light source is vertically arranged in the photoreactor, and the detachable light source is used to generate VUV; a constant temperature water bath layer is sleeved on the outer side of the photoreactor; the liquid circulation system comprises: a magnetic stirrer, a liquid outlet pipe, a liquid return pipe and a sample container, one end of the liquid outlet pipe is connected to the sample container, the other end of the liquid outlet pipe is detachably connected to the high-purity quartz annular reaction layer, one end of the liquid return pipe is connected to the sample container, and the other end of the liquid return pipe is detachably connected to the high-purity quartz annular reaction layer; the magnetic stirrer is used to place the sample container, a magnetic stirring rotor is placed in the sample container, and a peristaltic pump is connected to the middle part of the liquid outlet pipe.

2. The method according to claim 1, characterized in that The step of reacting under VUV irradiation to degrade the dye in the reaction solution comprises: The water molecules in the reaction solution are decomposed by VUV light to produce HO ● , HO ● Used to degrade dyes in reaction solutions.

3. The method according to claim 1, characterized in that The step of reacting under VUV irradiation to degrade the dye in the reaction solution comprises: PS in the reaction solution is decomposed by VUV photolysis to generate reactive oxygen species (ROSs), which are used to degrade the dye in the reaction solution.

4. The method according to claim 3, characterized in that The ROSs include: HO ● HO2 ● 、O2 ●- 、SO4 ●- 、SO5 ●- and S2O8 ●- .

5. The method according to claim 1, characterized in that The pH of the reaction solution was adjusted with different phosphate solutions so that the total concentration of phosphate species was 2.0 mM.

6. The method according to claim 5, characterized in that Phosphate solutions include: H3PO4, NaH2PO4, Na2HPO4 and Na3PO4; Phosphate species, including: PO4 3- 、HPO4 2- 、H2PO 4- and H3PO4.

7. The method according to claim 1, characterized in that The dye is methylene blue MB.

8. The method according to claim 1, characterized in that Before adding the sample water containing the dye into the sample container of the photoreaction device, the method further comprises: Install a VUV or UV lamp to the photoreaction device; the detachable light source is a VUV or UV lamp; Turn on the cooling circulator, pump ultrapure water into the constant temperature water bath through the cooling water inlet and discharge it back through the cooling water outlet; Turn on the VUV lamp of the photoreaction device to preheat the irradiation chamber; Open the high-purity N2 gas cylinder, and continuously pass high-purity N2 into the irradiation chamber through the high-purity N2 gas inlet and discharge it from the high-purity N2 exhaust port, so that the irradiation chamber is filled with high-purity N2.

9. The method according to claim 1, characterized in that: The method further comprises: After the reaction is completed, the solution in the high-purity quartz annular reaction layer is drained, and ultrapure water is injected to thoroughly clean the inlet and outlet connecting hoses and the inner wall of the high-purity quartz annular reaction layer. After cleaning, the water in the connecting hose and the high-purity quartz annular reaction layer is drained and the peristaltic pump is stopped.

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