System and method for treating organic pollutants in water based on microreactor ultrasonic piezoelectric catalysis of persulfate

Abstract

The application discloses a system and method for treating organic pollutants in water based on a micro-reactor ultrasonic piezoelectric catalysis persulfate, which comprises feeding device, ultrasonic micro-reactor and product collecting device connected in sequence; the ultrasonic micro-reactor comprises a micro-reaction chip, a piezoelectric ceramic sheet and an ultrasonic source assembly, the piezoelectric ceramic sheet is in contact with the micro-reaction chip, the ultrasonic source assembly is connected with the piezoelectric ceramic sheet through a wire, the micro-reaction chip is provided with a micro-channel, and the inlet flow channel and the outlet flow channel of the micro-channel correspond to the liquid inlet and the liquid outlet of the micro-reaction chip respectively. The micro-reactor is combined with the ultrasonic piezoelectric catalysis persulfate technology, so that the reaction materials are transported in the micro-channel, the ultrasonic piezoelectric catalysis degradation reaction of the reaction materials is carried out through the ultrasonic source assembly, the ultrasonic energy utilization rate is significantly improved, the degradation rate is improved to shorten the reaction time, and the efficient degradation of the organic pollutants in water is realized.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, and more specifically, to a system and method for treating organic pollutants in water based on ultrasonic pressure electrocatalytic persulfate treatment using a microreactor. Background Technology

[0002] Organic pollutants in the aquatic environment are difficult to remove and highly hazardous, posing potential threats to ecosystems and human health. While physical methods such as adsorption, coagulation, and membrane filtration can treat some organic pollutants, they cannot achieve the transformation of these pollutants. Advanced oxidation technologies, on the other hand, can degrade and even mineralize pollutants through the oxidation of reactive oxygen species. Among these, persulfate-based advanced oxidation technologies are widely used for the oxidative degradation of various organic pollutants in water. Although persulfate alone can achieve the direct oxidation of some organic pollutants, the degradation depth is low, and a large number of highly toxic oxidation products are generated. To improve the degradation depth, persulfate needs to be activated to form more potent reactive oxygen species such as sulfate radicals.

[0003] In recent years, piezoelectric / catalyst / persulfate systems constructed by introducing piezoelectric fields into the advanced oxidation process of persulfate have attracted researchers' attention. In this reaction system, atomic dislocations in the catalyst lattice under external force cause the centers of positive and negative charges to shift, forming a piezoelectric field, which in turn leads to the separation of electrons and holes, and further interacts with persulfate to form various reactive oxygen species.

[0004] Although the piezoelectric / catalyst / persulfate system can efficiently and stably degrade organic pollutants, the high energy consumption caused by the mechanical force required to drive the piezoelectric effect limits the practical application of the reaction system. Currently, ultrasound is the most widely used mechanical force in piezoelectric catalysis. However, in conventional-scale ultrasonic piezoelectric catalytic reactions to treat organic pollutants in water, the mismatch between the reactor size and the ultrasonic field during the reaction process results in high acoustic energy near the ultrasonic source and low acoustic energy far from the ultrasonic source, leading to an uneven distribution of the ultrasonic field. Locations with low acoustic energy cannot effectively drive the generation of the piezoelectric effect, and catalyst particles are prone to agglomeration, further reducing the catalytic effect. To ensure a better catalytic effect, the ultrasonic power needs to be increased to ensure sufficient acoustic energy intensity at all locations, which leads to low utilization efficiency of ultrasonic energy and limits the performance of the catalyst. At the same time, in the piezoelectric / catalyst / persulfate advanced oxidation reaction system, the efficient degradation of pollutants depends on the oxidation of reactive oxygen species, which have a very short lifetime and can only diffuse to the micron-scale region near the catalyst surface. In conventional-scale reaction systems, the diffusion of reactants such as persulfate and contaminants from the liquid phase to the vicinity of the catalyst surface, as well as the diffusion of reactive oxygen species generated during the reaction to the liquid phase, all require a relatively long distance. In addition, the agglomeration of catalyst particles reduces the solid-liquid interface, which is not conducive to the generation of reactive oxygen species and the degradation of contaminants. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned defects in the prior art and provide a system and method for treating organic pollutants in water based on ultrasonic piezoelectric persulfate treatment using a microreactor. By combining microreactor technology with ultrasonic piezoelectric persulfate technology, the utilization rate of ultrasonic energy is significantly improved, and the degradation rate is increased to shorten the reaction time, thereby achieving efficient degradation of organic pollutants in water.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A system for treating organic pollutants in water using ultrasonic piezoelectric persulfate based on a microreactor includes a feeding device, an ultrasonic microreactor, and a product collection device. The feeding device is connected to the ultrasonic microreactor and is used to transport reactants into the ultrasonic microreactor. The reactants include water containing organic pollutants, persulfate, and a catalyst. The ultrasonic microreactor includes a microreactor chip with a liquid inlet and a liquid outlet on its surface. Microchannels are also provided within the microreactor chip, with the inlet and outlet channels of the microchannels corresponding to the liquid inlet and liquid outlet, respectively. The reactants are transported through the feeding device and the liquid... The liquid flows in through the inlet, passes through the inlet channel and the outlet channel, and then exits through the liquid outlet. The ultrasonic microreactor also includes a piezoelectric ceramic sheet and an ultrasonic source assembly. The piezoelectric ceramic sheet is in contact with the microreactor chip, and the ultrasonic source assembly is connected to the piezoelectric ceramic sheet via a wire. The piezoelectric ceramic sheet is used to receive ultrasonic signals emitted from the ultrasonic source assembly, and the microreactor chip is used to receive and convert the ultrasonic signals received by the piezoelectric ceramic sheet to catalytically degrade organic pollutants in the water within the microchannel. The product collection device is connected to the liquid outlet and is used to collect the target product solution discharged through the liquid outlet.

[0008] This invention also provides a method for treating organic pollutants in water using ultrasonic pressure electrocatalytic persulfate based on a microreactor, employing the system described above for treating organic pollutants in water using ultrasonic pressure electrocatalytic persulfate based on a microreactor; the method includes the following steps:

[0009] Water containing organic pollutants, catalyst, and persulfate are mixed to obtain the reaction mixture;

[0010] The reactants are fed into the microchannel of the ultrasonic microreactor through the feeding device. The ultrasonic source component is activated so that the reactants are transported in the microchannel while the ultrasonic source component performs an ultrasonic piezoelectric catalytic degradation reaction on the reactants in the microchannel to obtain an intermediate liquid.

[0011] The intermediate liquid discharged through the liquid outlet is collected, and the catalyst is separated to obtain the target product solution.

[0012] Implementing the embodiments of the present invention will have the following beneficial effects:

[0013] (1) The size of the ultrasonic microreactor of the present invention is matched with the length of the ultrasonic wave, so the sound energy distribution is uniform and the ultrasonic energy utilization efficiency is high. The ultrasonic frequency commonly used in ultrasonic piezoelectric catalytic reaction is tens of kilohertz, which corresponds to a wavelength of several centimeters in water. Based on this, the present invention uses a microreactor chip that matches the wavelength to ensure uniform sound field intensity in the ultrasonic microreactor, thereby achieving high ultrasonic energy utilization efficiency. This solves the problem of low ultrasonic energy utilization efficiency caused by the mismatch between the ultrasonic field and the reactor size during the reaction process, resulting in uneven sound energy distribution.

[0014] (2) The size of the ultrasonic microreactor of the present invention is matched with the diffusion distance of the reactants, which is beneficial to the generation and participation of reactive oxygen species in the reaction. The present invention significantly shortens the diffusion distance between reactants and reactive oxygen species by employing microchannels with characteristic dimensions on the sub-millimeter scale; simultaneously, the uniform intensity of ultrasound and the limited channel size inhibit the aggregation of catalyst particles and increase the solid-liquid interface. Therefore, the ultrasonic microreactor of the present invention can promote the generation of reactive oxygen species and the degradation of pollutants.

[0015] Based on the above advantages, combining microreactor technology with ultrasonic piezoelectric persulfate technology can significantly improve the utilization rate of ultrasonic energy and increase the degradation rate to shorten the reaction time, thereby achieving efficient degradation of organic pollutants in water. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a microreactor-based ultrasonic pressure electrocatalytic persulfate system for treating organic pollutants in water, according to an embodiment of the present invention. Detailed Implementation

[0017] The present invention will be further described below with reference to specific embodiments, but this does not limit the present invention in any way.

[0018] The inventors have discovered that microreactors, unlike conventional scale reaction systems, can have channel characteristic dimensions down to the sub-millimeter level. Due to their advantages such as high mass transfer rates, easy process control, and direct scale-up, they have been applied in environmental, chemical, and pharmaceutical fields, with some reactions already industrialized. Based on this, the inventors have creatively combined microreactor technology with an ultrasonic piezoelectric / catalyst / persulfate advanced oxidation reaction system for the first time, solving the problem of high energy consumption and its limitation on practical application faced by existing conventional scale reaction systems.

[0019] Therefore, the present invention is specifically as follows.

[0020] This invention discloses a system for treating organic pollutants in water based on ultrasonic pressure electrocatalytic persulfate treatment using a microreactor, such as... Figure 1 As shown, Figure 1 This is a schematic diagram of a microreactor-based ultrasonic piezoelectric catalytic persulfate system for treating organic pollutants in water, according to an embodiment of the present invention. The system includes a feeding device 100, an ultrasonic microreactor 200, and a product collection device 300. The feeding device 100 is connected to the ultrasonic microreactor 200 and is used to transport the reactants into the ultrasonic microreactor 200. The reactants include water containing organic pollutants, persulfate, and a catalyst. The ultrasonic microreactor 200 includes a microreactor chip 210. The surface of the microreactor chip 210 is provided with a liquid inlet 211 and a liquid outlet 212. A microchannel 213 is also provided inside the microreactor chip 210. The inlet and outlet channels of the microchannel 213 correspond to the liquid inlet 211 and the liquid outlet 212, respectively. The reactants are fed through the feeding device 100. The liquid enters through the liquid inlet 211, flows through the inlet channel and outlet channel, and exits through the liquid outlet 212. The ultrasonic microreactor 200 also includes a piezoelectric ceramic sheet 220 and an ultrasonic source assembly 230. The piezoelectric ceramic sheet 220 is in contact with the microreactor chip 210. The ultrasonic source assembly 230 is connected to the piezoelectric ceramic sheet 220 through a wire. The piezoelectric ceramic sheet 220 is used to receive ultrasonic signals emitted from the ultrasonic source assembly 230. The microreactor chip 210 is used to receive and convert the ultrasonic signals received from the piezoelectric ceramic sheet 220 to catalytically degrade organic pollutants in the water within the microchannel 213. The product collection device 300 is connected to the liquid outlet 212 and is used to collect the target product solution discharged through the liquid outlet 212.

[0021] Specifically, by employing a micro-reaction chip 210 that matches the length of the ultrasonic wave, this invention ensures uniform sound field intensity in the ultrasonic microreactor 200, thereby achieving high ultrasonic energy utilization efficiency. This solves the problem of low ultrasonic energy utilization efficiency caused by the mismatch between the ultrasonic field and the reactor size during the reaction process, resulting in uneven sound energy distribution.

[0022] In one specific embodiment, the microchannel 213 includes one of a single channel and a multi-channel.

[0023] In one specific embodiment, Figure 1 The microchannel 213 is shown to be spiral-shaped, but it is not limited to this. The microchannel 213 in this embodiment may also include one or more of the following: straight line, broken line, and curved line.

[0024] In one specific embodiment, the channel height of the microchannel 213 is 5μm to 500μm.

[0025] In one specific embodiment, the channel height of the microchannel 213 includes, but is not limited to, 5μm, 100μm, 200μm, 300μm, 400μm, 500μm, etc.

[0026] In one specific embodiment, the channel length of the microchannel 213 is 10mm to 500mm.

[0027] In one specific embodiment, the channel length of the microchannel 213 includes, but is not limited to, 10mm, 100mm, 200mm, 300mm, 400mm, and 500mm.

[0028] In one specific embodiment, the channel width of the microchannel 213 is 100μm to 2000μm.

[0029] In one specific embodiment, the channel width of the microchannel 213 includes, but is not limited to, 100μm, 500μm, 800μm, 1000μm, 1500μm, 2000μm, etc.

[0030] Specifically, this invention significantly shortens the diffusion distance between reactants and reactive oxygen species by employing microchannels 213 with sub-millimeter dimensions. Simultaneously, the uniform intensity of ultrasound and the limited channel size suppress catalyst particle aggregation and increase the solid-liquid interface. Therefore, the ultrasonic microreactor 200 of this invention has a size matched to the diffusion distance of reactants, which can promote the generation of reactive oxygen species and the degradation of pollutants.

[0031] In one specific embodiment, the number of microreaction chips 210 is one or more.

[0032] In one specific embodiment, the microreaction chip 210 is made of one or more of the following materials: silicon, quartz, glass, stainless steel, aluminum, polydimethylsiloxane, polymethyl methacrylate, polycarbonate, polyethylene, polystyrene, and polypropylene.

[0033] In one specific embodiment, the piezoelectric ceramic sheet 220 is made of one or more of the following materials: quartz, barium titanate, strontium titanate, lead titanate, lead zirconate titanate, zinc oxide, zinc sulfide, molybdenum sulfide, and tungsten sulfide.

[0034] In one specific embodiment, the shape of the piezoelectric ceramic sheet 220 includes one or both of circular and square shapes.

[0035] In one specific embodiment, the thickness of the piezoelectric ceramic sheet 220 is 0.1 mm to 10 mm.

[0036] In one specific embodiment, the thickness of the piezoelectric ceramic sheet 220 includes, but is not limited to, 0.1 mm, 1 mm, 5 mm, 8 mm, 10 mm, etc.

[0037] In one specific embodiment, the natural frequency of the piezoelectric ceramic sheet 220 is 1 kHz to 10 MHz.

[0038] In one specific embodiment, the piezoelectric ceramic sheet 220 contacts the microreactive chip 210 in one or more of the following ways: direct placement, pasting, and embedding.

[0039] In one specific embodiment, the piezoelectric ceramic sheet 220 is located in one or more of the upper, lower and side portions of the microreactive chip 210.

[0040] In one specific embodiment, the overall effect is optimal when the number of piezoelectric ceramic sheets 220 in contact with each microreactor chip 210 is 1 to 6.

[0041] In one specific embodiment, the ultrasonic source assembly 230 includes an ultrasonic generator 231, a power amplifier 232, and an impedance matching device 233 connected in sequence by wires. The impedance matching device 233 and the piezoelectric ceramic sheet 220 are connected by wires.

[0042] In one specific embodiment, the feeding device 100 includes a first liquid container 110 and a pump 120; the first liquid container 110, the pump 120 and the ultrasonic microreactor 200 are connected in sequence to form a conveying channel, and the pump 120 is used to push the reactants to flow in the conveying channel.

[0043] In one specific embodiment, the product collection device 300 is a second liquid container. In actual operation, the product collection device 300 can flexibly use liquid containers of different sizes to facilitate the collection of different amounts of target product solution.

[0044] In one specific embodiment, the water containing organic pollutants includes water containing one or more of dyes, antibiotics, phenols, and endocrine disruptors.

[0045] In one specific embodiment, the persulfate includes one or more of potassium peroxymonosulfonate, sodium peroxymonosulfonate, potassium persulfate, sodium persulfate, and ammonium persulfate.

[0046] In one specific embodiment, the catalyst includes one or more of the following: quartz, barium titanate, strontium titanate, lead titanate, lead zirconate titanate, zinc oxide, zinc sulfide, molybdenum sulfide, and tungsten sulfide.

[0047] The present invention also discloses a method for treating organic pollutants in water based on ultrasonic pressure electrocatalytic persulfate treatment using a microreactor, employing a system for treating organic pollutants in water based on ultrasonic pressure electrocatalytic persulfate treatment using a microreactor as described in any embodiment of the present invention.

[0048] Furthermore, the method for treating organic pollutants in water using ultrasonic piezoelectric persulfate based on a microreactor includes the following steps:

[0049] S1. Mix water containing organic pollutants, catalyst and persulfate to obtain the reaction material.

[0050] In one specific embodiment, mixing includes one or more of stirring, oscillation, and ultrasound.

[0051] In one specific embodiment, the concentration of organic pollutants in the water is 1 mg / L to 200 mg / L.

[0052] In one specific embodiment, the catalyst dosage is 0.01 g / L to 2 g / L.

[0053] In one specific embodiment, the dosage of persulfate is 0.01 g / L to 5 g / L.

[0054] S2. The reactants are fed into the microchannel 213 of the ultrasonic microreactor 200 through the feeding device 100. The ultrasonic source component 230 is activated so that while the reactants are being transported in the microchannel 213, the ultrasonic source component 230 performs an ultrasonic piezoelectric catalytic degradation reaction on the reactants in the microchannel 213 to obtain an intermediate liquid.

[0055] In one specific embodiment, the flow rate of the reactants is 0.01 mL / min to 5 mL / min.

[0056] In one specific embodiment, the ultrasonic frequency of the ultrasonic source component 230 is 20 Hz to 100 kHz; the ultrasonic power of the ultrasonic source component 230 is 0 W to 200 W.

[0057] S3. Collect the intermediate liquid discharged through liquid outlet 212 and separate the catalyst to obtain the target product solution.

[0058] In one specific embodiment, the separation method in step S3 is not particularly limited, and any separation method well known to those skilled in the art can be used, including but not limited to centrifugation, filtration and other steps.

[0059] Specifically, the inventors explain the inventive principle of this application as follows: This invention integrates the advantages of ultrasonic piezoelectric catalytic persulfate technology and microchannel water treatment technology. Under ultrasonic conditions, atomic dislocations in the catalyst lattice cause the centers of positive and negative charges to shift, forming a piezoelectric field, which in turn leads to the separation of electrons and holes. The separated electrons further react with persulfate to form various reactive oxygen species (forming sulfate radicals, hydroxyl radicals, singlet oxygen, etc.), achieving rapid and efficient oxidative decomposition of organic pollutants, and has high application value and environmental benefits.

[0060] The following are specific embodiments.

[0061] Example 1

[0062] This embodiment of a system for treating organic pollutants in water using ultrasonic piezoelectric catalysis persulfate based on a microreactor includes a reaction material container, a pump, an ultrasonic microreactor, and a target product container connected in sequence. The ultrasonic microreactor comprises a microreactor chip, a piezoelectric ceramic sheet, an impedance matching instrument, a power amplifier, and an ultrasonic generator connected in sequence. The microreactor chip is made of polydimethylsiloxane, and there is one chip containing a single, spiral-shaped microchannel with a height of 50 μm, a length of 300 mm, and a width of 300 μm. The piezoelectric ceramic sheet is made of lead zirconate titanate, and there is one chip. It is circular, 2 mm thick, and has a natural frequency of 4 MHz. The piezoelectric ceramic sheet is embedded in the lower part of the microreactor chip.

[0063] The processing method in this embodiment, using the above-described system, specifically includes the following steps:

[0064] S1. Zinc oxide is dispersed by shaking in water containing sulfamethoxazole, and potassium persulfonate is added to obtain the reaction mixture. The concentration of sulfamethoxazole in the water is 20 mg / L. The dosage of zinc oxide is 1 g / L. The dosage of potassium persulfonate is 0.4 g / L.

[0065] S2. The reactants are pumped into the microchannels of the ultrasonic microreactor at a flow rate of 0.2 mL / min. The ultrasonic generator, power amplifier, and impedance matching instrument are activated, allowing the reactants to undergo an ultrasonic piezoelectric catalytic advanced oxidative degradation reaction within the ultrasonic microreactor while being transported within the microchannels, yielding an intermediate liquid. The ultrasonic frequency is 40 kHz, and the ultrasonic power is 20 W. Calculations show that the reaction time is 1.35 seconds.

[0066] S3. Collect the intermediate liquid discharged through the liquid outlet and separate the zinc oxide to obtain the target product solution. Analyze the intermediate liquid and find that the sulfamethoxazole removal rate is 95%.

[0067] Example 2

[0068] This embodiment of a system for treating organic pollutants in water using ultrasonic piezoelectric catalysis persulfate based on a microreactor includes a reaction material container, a pump, an ultrasonic microreactor, and a target product container connected in sequence. The ultrasonic microreactor comprises a microreactor chip, piezoelectric ceramic sheets, an impedance matching instrument, a power amplifier, and an ultrasonic generator connected in sequence. The microreactor chip is made of polymethyl methacrylate, and there is one chip containing a single, spiral-shaped microchannel with a height of 10 μm, a length of 500 mm, and a width of 120 μm. Three piezoelectric ceramic sheets are made of lead titanate, are circular in shape, 1 mm thick, and have a natural frequency of 1 MHz. The piezoelectric ceramic sheets are embedded in the lower part of the microreactor chip.

[0069] The processing method in this embodiment, using the above-described system, specifically includes the following steps:

[0070] S1. Lead titanate is dispersed by shaking in water containing sulfamethoxazole, and sodium persulfate is added to obtain the reaction mixture. The concentration of sulfamethoxazole in the water is 5 mg / L, the dosage of lead titanate is 0.05 g / L, and the dosage of sodium persulfate is 0.1 g / L.

[0071] S2. The reactants are pumped into the microchannels of the ultrasonic microreactor at a flow rate of 0.05 mL / min. The ultrasonic generator, power amplifier, and impedance matching instrument are activated, allowing the reactants to undergo an ultrasonic piezoelectric catalytic advanced oxidative degradation reaction within the ultrasonic microreactor while being transported within the microchannels, yielding an intermediate liquid. The ultrasonic frequency is 80 kHz, the ultrasonic power is 50 W, and the calculated reaction time is 0.72 seconds.

[0072] S3. Collect the intermediate liquid discharged through the liquid outlet and separate lead titanate to obtain the target product solution. Analyze the intermediate liquid and find that the removal rate of sulfamethoxazole is 98%.

[0073] Example 3

[0074] This embodiment of the system for treating organic pollutants in water based on ultrasonic piezoelectric catalytic persulfate treatment using a microreactor includes a reaction material container, a pump, an ultrasonic microreactor, and a target product container connected in sequence. The ultrasonic microreactor includes a microreactor chip, a piezoelectric ceramic plate, an impedance matching device, a power amplifier, and an ultrasonic generator connected in sequence.

[0075] The microreactor chip is made of glass and consists of a single, spiral-shaped microchannel. The microchannel has a height of 200 μm, a length of 50 mm, and a width of 1800 μm. The piezoelectric ceramic sheet is made of barium titanate, is circular in shape, 10 mm thick, and has a natural frequency of 50 kHz. The piezoelectric ceramic sheet is embedded in the lower part of the microreactor chip, where it contacts the microreactor chip.

[0076] The processing method in this embodiment, using the above-described system, specifically includes the following steps:

[0077] S1. Molybdenum sulfide is dispersed by shaking in water containing sulfamethoxazole, and potassium persulfate is added to obtain the reaction mixture. The concentration of sulfamethoxazole in the water is 150 mg / L, the dosage of molybdenum sulfide is 1.6 g / L, and the dosage of potassium persulfate is 4 g / L.

[0078] S2. The reactants are pumped into the microchannels of the ultrasonic microreactor at a flow rate of 2 mL / min. The ultrasonic generator, power amplifier, and impedance matching instrument are activated, allowing the reactants to undergo an ultrasonic piezoelectric catalytic advanced oxidative degradation reaction within the ultrasonic microreactor while being transported within the microchannels, yielding an intermediate liquid. The ultrasonic frequency is 65 kHz, the ultrasonic power is 200 W, and the calculated reaction time is 0.54 seconds.

[0079] S3. Collect the intermediate liquid discharged through the liquid outlet and separate molybdenum sulfide to obtain the target product solution. Analyze the intermediate liquid and find that the removal rate of sulfamethoxazole is 87%.

[0080] Comparative Example 1

[0081] The only difference between this comparative example and Example 1 is that a conventional-scale ultrasonic reactor was used to treat water containing sulfamethoxazole. Specifically, the persulfate was potassium persulfonate, the catalyst was zinc oxide, the sulfamethoxazole concentration was 20 mg / L, the zinc oxide dosage was 1 g / L, the zinc oxide was dispersed in the water by shaking, the persulfate dosage was 0.4 g / L, the ultrasonic frequency was 40 kHz, and the ultrasonic power was 20 W. Samples were taken for analysis at 1 min, 3 min, 5 min, 10 min, 20 min, and 30 min of reaction, and the corresponding sulfamethoxazole removal rates were 23%, 36%, 49%, 62%, 62%, and 62%, respectively.

[0082] Comparing the treatment results of Example 1 (using an ultrasonic microreactor) and Comparative Example 1 (using a conventional-scale ultrasonic reactor): In Example 1, the reaction time in the ultrasonic microreactor was only 1.35 seconds, achieving a sulfamethoxazole removal rate of 95%. In Comparative Example 1, the sulfamethoxazole removal rate reached its maximum of 62% at a reaction time of 10 minutes, and then did not increase further. The reaction time in Example 1's ultrasonic microreactor was significantly shorter than that in Comparative Example 1's conventional-scale ultrasonic reactor, yet the sulfamethoxazole removal rate was much higher. This confirms that the present invention integrates the advantages of ultrasonic piezoelectric catalytic persulfation technology and microchannel water treatment technology, and that the method of treating organic pollutants in water using ultrasonic piezoelectric catalytic persulfation within a microreactor has a better treatment effect.

[0083] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for treating organic pollutants in water based on microreactor ultrasonic piezoelectric catalysis of persulfate, characterized in that, The system for treating organic pollutants in water by ultrasonic piezoelectric catalysis of persulfate based on a microreactor; The system for treating organic pollutants in water by ultrasonic piezoelectric catalysis of persulfate based on a microreactor, comprising a feeding device, an ultrasonic microreactor and a product collecting device; The feeding device is in communication with the ultrasonic microreactor for delivering reactants to the ultrasonic microreactor; the reactants comprise water containing organic pollutants, persulfate and a catalyst; The ultrasonic microreactor comprises a microreaction chip, the surface of the microreaction chip is provided with a liquid inlet and a liquid outlet, and the microreaction chip is further provided with a microchannel, the inlet flow channel and the outlet flow channel of the microchannel correspond to the liquid inlet and the liquid outlet respectively, the reactants flow into the microchannel through the liquid inlet, and then flow out of the microchannel through the liquid outlet after passing through the inlet flow channel and the outlet flow channel in sequence; The ultrasonic microreactor further comprises a piezoelectric ceramic sheet and an ultrasonic source assembly; The piezoelectric ceramic sheet is in contact with the microreaction chip, the ultrasonic source assembly is connected with the piezoelectric ceramic sheet through a wire, the piezoelectric ceramic sheet is used for receiving ultrasonic signals emitted from the ultrasonic source assembly, and the microreaction chip is used for receiving ultrasonic signals emitted from the piezoelectric ceramic sheet after being converted to catalytically degrade organic pollutants in water in the microchannel; The product collecting device is in communication with the liquid outlet for collecting target product solution discharged through the liquid outlet; The channel shape of the microchannel comprises one or more than two of a broken line type, a curve type and a spiral line type; the channel length of the microchannel is 50mm-500mm; The concentration of organic pollutants in the water containing organic pollutants is 1mg / L-200mg / L; The dosage of the catalyst is 0.01g / L-2g / L; The dosage of the persulfate is 0.01g / L-5g / L; The ultrasonic frequency of the ultrasonic source assembly is 20Hz-100kHz; The ultrasonic power of the ultrasonic source assembly is 0W-200W; The method comprises the following steps: Mixing water containing organic pollutants, a catalyst and persulfate to obtain reactants; Feeding the reactants into the microchannel of the ultrasonic microreactor through the feeding device, starting the ultrasonic source assembly, and performing ultrasonic piezoelectric catalytic degradation reaction on the reactants in the microchannel through the ultrasonic source assembly to obtain intermediate liquid; Collecting the intermediate liquid discharged through the liquid outlet and separating the catalyst to obtain target product solution.

2. The method for treating organic pollutants in water by microreactor-based ultrasound piezocatalysis with persulfate according to claim 1, characterized in that, The microchannel comprises one of a single channel and a plurality of channels; The channel height of the microchannel is 5μm-500μm, and the channel width of the microchannel is 100μm-2000μm.

3. The method for treating organic pollutants in water by microreactor-based ultrasound piezocatalysis with persulfate according to claim 1, characterized in that, The number of the microreaction chips is one or more; The material of the microreaction chip comprises one or more than two of silicon, quartz, glass, stainless steel, aluminum, polydimethylsiloxane, polymethyl methacrylate, polycarbonate, polyethylene, polystyrene and polypropylene.

4. The method for treating organic pollutants in water by microreactor-based ultrasound piezocatalysis with persulfate according to claim 1, characterized in that, The material of the piezoelectric ceramic sheet comprises one or more than two of quartz, barium titanate, strontium titanate, lead titanate, lead zirconate titanate, zinc oxide, zinc sulfide, molybdenum sulfide and tungsten sulfide; The shape of the piezoelectric ceramic sheet comprises one or more than two of a circle and a square; The thickness of the piezoelectric ceramic sheet is 0.1mm-10mm; The natural frequency of the piezoelectric ceramic sheet is 1kHz-10MHz.

5. The method for treating organic pollutants in water by microreactor-based ultrasound piezocatalysis with persulfate according to claim 1, characterized in that, The contact mode of the piezoelectric ceramic sheet with the micro-reaction chip comprises one or more than two of direct placement, sticking and inlaying; The piezoelectric ceramic sheet is located at one or more than two of the upper part, the lower part and the side part of the micro-reaction chip; The number of piezoelectric ceramic sheets in contact with each micro-reaction chip is 1-6.

6. The method for treating organic pollutants in water by microreactor-based ultrasound piezocatalysis with persulfate according to claim 1, characterized in that, The ultrasonic source assembly comprises an ultrasonic generator, a power amplifier and an impedance matching instrument connected in sequence by wires, and the impedance matching instrument and the piezoelectric ceramic sheet are connected by wires.

7. The method for treating organic pollutants in water by microreactor-based ultrasound piezocatalysis of persulfate according to claim 1, characterized in that, The feeding device comprises a first liquid container and a pump; The first liquid container, the pump and the ultrasonic micro-reactor are connected in sequence to form a delivery flow channel, and the pump is used to push the reaction material to flow in the delivery flow channel; The product collection device is a second liquid container.

8. The method for treating organic pollutants in water by microreactor-based ultrasound piezocatalysis with persulfate according to claim 1, characterized in that, The water containing organic pollutants comprises water containing one or more than two of dyes, antibiotics, phenols and endocrine disruptors; The persulfate salt comprises one or more than two of potassium peroxymonosulfate, sodium peroxymonosulfate, potassium peroxodisulfate, sodium peroxodisulfate and ammonium peroxodisulfate; The catalyst comprises one or more than two of quartz, barium titanate, strontium titanate, lead titanate, lead zirconate titanate, zinc oxide, zinc sulfide, molybdenum sulfide and tungsten sulfide.

9. The method for treating organic pollutants in water by microreactor-based ultrasound piezocatalysis with persulfate according to claim 1, characterized in that, The mixing comprises one or more than two of stirring, oscillation and ultrasonic; The delivery flow rate of the reaction material is 0.01mL / min-5mL / min.

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