Method for degrading new pollutants in water by activating CuII-PMS system through plasma

Abstract

The invention discloses a method for degrading new pollutants in water by activating a CuII-PMS system through plasma, which comprises the following steps: adding bivalent copper salt and peroxymonosulfate into to-be-treated wastewater containing pollutants to obtain a mixed wastewater solution; continuously introducing working gas into the mixed wastewater solution to obtain a wastewater solution with uniformly mixed gas; a wastewater solution with uniformly mixed gas is introduced into low-temperature plasma, so that active substances generated by the low-temperature plasma are in full contact with the wastewater solution with uniformly mixed gas to generate more hydroxyl free radicals and sulfate free radicals, and meanwhile, the hydroxyl free radicals and the sulfate free radicals act on pollutants together with other active substances generated by the low-temperature plasma; the degradation of pollutants is realized; the technical problem that the efficiency of degrading pollutants in water by plasmas is low is solved.

Description

Technical Field

[0001] The present invention relates to the field of degradation of new pollutants in water, and in particular to plasma activated Cu Ⅱ -Method of PMS system for degrading new pollutants in water. Background Art

[0002] With the continuous development of urbanization, industrialization and agricultural production, new pollutants are increasingly polluting water bodies. At present, new pollutants that are widely concerned at home and abroad mainly include persistent organic pollutants, endocrine disruptors, antibiotics, etc. controlled by international conventions. The production and use of toxic and harmful chemicals are the main sources of new pollutants. Compared with conventional pollutants, new pollutants are of various types, highly toxic, and have the characteristics of environmental persistence and bioaccumulation. Therefore, the efficient removal of new pollutants is a difficult problem that we urgently need to solve. Advanced oxidation technology (AOPs) is characterized by the production of free radicals with strong oxidizing ability (mostly hydroxyl free radicals). Under the reaction conditions of high temperature, high pressure, electricity, sound, light radiation and catalysts, large molecular refractory organic matter is oxidized into low-toxic or non-toxic small molecules. Among them, low-temperature plasma is a new type of composite AOPs that integrates light, electricity and chemical oxidation. It has the advantages of high efficiency, non-selectivity, low cost and no secondary pollution. It is considered to be one of the most promising wastewater treatment technologies.

[0003] A large amount of gas-phase active substances will be generated during the low-temperature plasma treatment process. These active substances need to pass through the gas-liquid interface and enter the liquid phase through diffusion, radiation and other methods before they can react with pollutants to achieve the goal of degradation. This process will inevitably weaken the effect of active substances on pollutants. This makes low-temperature plasma face several major problems in degrading pollutants in water: first, the mass transfer efficiency of active substances across the gas-liquid interface is low; second, the utilization rate of various physical and chemical effects generated by low-temperature plasma is low. At present, many studies have been conducted to improve the problem of gas-liquid mass transfer by combining microbubble generators with low-temperature plasma, but the effect of improving the degradation rate of pollutants is still not ideal. Therefore, how to efficiently degrade pollutants in water remains a challenge. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problem of low efficiency of plasma degradation of pollutants in water in the prior art, and to provide a plasma activated Cu Ⅱ -Method of degrading new pollutants in water using PMS system.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: The invention discloses a plasma activated Cu Ⅱ -The method for degrading new pollutants in water by PMS system comprises the following steps: Adding divalent copper salt and peroxymonosulfate to the wastewater to be treated containing pollutants to obtain a mixed wastewater solution; Continuously introducing working gas into the mixed wastewater solution to obtain a wastewater solution with uniform gas mixing; The wastewater solution with uniform gas mixture is introduced into low-temperature plasma, so that the active substances generated by the low-temperature plasma are fully in contact with the wastewater solution with uniform gas mixture, more hydroxyl radicals and sulfate radicals are generated, and at the same time, they act on pollutants together with other active substances generated by the low-temperature plasma to achieve the degradation of pollutants.

[0006] Furthermore, the pollutant is a mixture of one or more of β-lactams, macrolides, aminoglycosides, tetracyclines, lincomycins, chloramphenicols and polypeptide antibiotics.

[0007] Furthermore, the concentration of the tetracycline antibiotic is 5 mg / L to 200 mg / L, and the concentration of peroxymonosulfate added is 0.1 to 0.5 g / L.

[0008] Furthermore, the concentration of the divalent copper salt is 0.005-0.1 g / L.

[0009] Furthermore, the peroxymonosulfate is a mixture of one or more of sodium persulfate or potassium persulfate.

[0010] Furthermore, the working gas is oxygen, air, argon or nitrogen.

[0011] Furthermore, the flow rate of the introduced working gas is 0.2~5L / min.

[0012] Furthermore, the low-temperature plasma discharge device adopts a pulse power supply, and the voltage of the pulse power supply is 6.5~8.5kV.

[0013] Furthermore, the time duration for the low-temperature plasma treatment gas to mix the wastewater solution evenly is 0 to 20 minutes.

[0014] Furthermore, the divalent copper salt may be replaced by iron or manganese ions.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The invention discloses a plasma activated Cu Ⅱ -PMS system is used to degrade new pollutants in water, in which oxygen plasma can efficiently activate Cu Ⅱ -PMS system produces high concentration of free radicals, achieving efficient degradation of pollutants in water. This method mainly includes Fenton-like reaction, Cu Ⅰ / Cu ⅡCycle and oxygen-sulfur free radical cycle and a series of chain reactions. Among them, hydrogen peroxide and Cu generated by low-temperature plasma similar to Fenton reaction Ⅱ The reaction produces hydroxyl radicals, thereby increasing the concentration of hydroxyl radicals in the system; Cu Ⅰ / Cu Ⅱ Cycling can accelerate electron transfer; low-temperature plasma can also activate PMS to produce sulfate radicals, introducing new active free radicals into the system, which can not only make full use of the various physical and chemical effects produced by low-temperature plasma, but also achieve efficient, continuous and multi-effect catalytic degradation of pollutant solutions.

[0016] Furthermore, the plasma activated Cu Ⅱ The -PMS system method for degrading new pollutants in water has the advantages of high efficiency, non-selectivity, low cost, and no secondary pollution. It can achieve continuous degradation of antibiotics, with a degradation efficiency of up to 95.73% within 20 minutes, which is conducive to the further development and industrial practical application of low-temperature plasma degradation technology for new pollutants in water. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 The plasma activated Cu Ⅱ -Schematic diagram of the structure of the device for degrading new pollutants in water by the PMS system; Figure 2 The degradation rate histogram of tetracycline hydrochloride in the wastewater solution at different PMS contents in the embodiment of the present invention; Figure 3 is a histogram of the degradation rate of tetracycline hydrochloride in the wastewater solution under different voltages according to an embodiment of the present invention; Figure 4 is a histogram of the degradation rate of tetracycline hydrochloride in the wastewater solution at different flow rates according to an embodiment of the present invention; Figure 5 For different Cu Ⅱ The degradation rate histogram of tetracycline hydrochloride in wastewater solution under the content; Figure 6 This is a graph showing the degradation rate of tetracycline hydrochloride in a wastewater solution under different gas low-temperature plasmas according to an embodiment of the present invention; Figure 7is a graph showing the degradation rate of tetracycline hydrochloride in a wastewater solution under different metal ion conditions in an embodiment of the present invention; Figure 8 This is a spectrum of hydroxyl radicals and sulfate radicals captured by the capture agent of the embodiment of the present invention; Fig. 9 The concentration distribution diagram of the active substance under different gases in the embodiment of the present invention; Fig.10 It is a line graph showing the effect of different concentrations of tert-butyl alcohol or ethanol on the degradation performance of tetracycline hydrochloride in the embodiment of the present invention; Fig.11 The absorbance curves of tetracycline hydrochloride at different treatment times according to the embodiments of the present invention are shown.

[0019] Among them: 1-ground electrode; 2-quartz glass tube; 3-micropore; 4-high voltage electrode, stainless steel metal rod; 5-high voltage pulse power supply; 6-gas flow meter; 7-gas storage cylinder. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and marked in the drawings here can be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0023] The present invention is further described in detail below in conjunction with the accompanying drawings: See also Figure 1 , the plasma activated Cu in the embodiment of the present invention Ⅱ-PMS system degradation of new pollutants in water device, including grounding electrode 1, quartz glass tube 2, high-voltage electrode 4, high-voltage pulse power supply 5, gas flow meter 6 and gas storage bottle 7; the gas storage bottle 7 is connected to the gas inlet at the upper part of the quartz glass tube 2, and the gas flow meter 6 is arranged between the gas storage bottle 7 and the gas inlet at the upper part of the quartz glass tube 2; a plurality of micropores 3 are arranged at the lower part of the quartz glass tube 2; the high-voltage electrode 4 is arranged inside the quartz glass tube 2, and the top of the high-voltage electrode 4 is connected to the high-voltage pulse power supply 5; the grounding electrode 1 is arranged in the wastewater solution; the quartz glass tube 2 is partially immersed in the wastewater solution.

[0024] Example 1 S1. Add 0.1 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 7.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0025] Example 2 S1. Add 0.3 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 7.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0026] Example 3 S1. Add 0.5 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 7.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0027] Example 4 S1. Add 0.5 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 6.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0028] Example 5 S1. Add 0.5 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0029] Example 6 S1. Add 0.5 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 0.2 L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0030] Example 7 S1. Add 0.5 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 0.5 L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0031] Example 8 S1. Add 0.5 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 5L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0032] Example 9 S1. Add 0.5 g / L PMS (potassium persulfate) and 0.005 g / L Cu into 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride. Ⅱ (copper sulfate pentahydrate), to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0033] Example 10 S1. Add 0.5 g / L PMS (potassium persulfate) and 0.05 g / L Cu into 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride. Ⅱ (copper sulfate pentahydrate), to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0034] Embodiment 11 S1. Add 0.5 g / L PMS (potassium persulfate) and 0.1 g / L Cu into 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride. Ⅱ (copper sulfate pentahydrate), to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0035] Example 12 S1. Add 0.5 g / L PMS (potassium persulfate) and 0.05 g / L Cu into 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride. Ⅱ (copper sulfate pentahydrate), to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow oxygen to continuously flow into the mixed wastewater solution at a set flow rate of 1 L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0036] Embodiment 13 S1. Add 0.5 g / L PMS (potassium persulfate) and 0.05 g / L Cu into 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride. Ⅱ (copper sulfate pentahydrate), to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow argon gas to continuously flow into the mixed wastewater solution at a set flow rate of 1 L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0037] Embodiment 14 S1. Add 0.5 g / L PMS (potassium persulfate) and 0.05 g / L Cu into 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride. Ⅱ (copper sulfate pentahydrate), to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow nitrogen to continuously flow into the mixed wastewater solution at a set flow rate of 1 L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0038] Embodiment 15 S1. Add 0.5 g / L PMS (potassium persulfate) and 0.05 g / L Mn to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride. Ⅱ (manganous chloride tetrahydrate), to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0039] Example 10 S1. Add 0.5 g / L PMS (potassium persulfate) and 0.05 g / L Fe to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride. Ⅱ (ferrous sulfate heptahydrate), to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 8.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0040] Comparative Example 1 S1. Add 0.5 g / L PMS (potassium persulfate) to 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride to obtain a mixed wastewater solution; S2, turn on the gas flow meter to allow air to continuously flow into the mixed wastewater solution at a set flow rate of 1L / min; S3. Turn off the high-voltage pulse power supply, and take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, for a total of 20 minutes.

[0041] Comparative Example 2 S1, taking 200 ml of wastewater solution containing 200 mg / L tetracycline hydrochloride; S2, turn on the gas flow meter to allow air to continuously flow into the wastewater solution at a set flow rate of 1L / min; S3. Turn on the high-voltage pulse power supply, and set the peak voltage and frequency of the high-voltage pulse power supply to 7.5 kV and 4 kHz respectively, so that various active substances generated by the low-temperature plasma are fully in contact with the wastewater solution uniformly mixed with gas. Take the treated wastewater for testing the tetracycline hydrochloride content every 5 minutes, and treat it for a total of 20 minutes.

[0042] Detection and analysis The treated wastewater solution was taken from Examples 1 to 3 and Comparative Examples 1 and 2 every 5 minutes, and the content of tetracycline hydrochloride was detected and analyzed using an ultraviolet spectrophotometer. The results are as follows: Figure 2 As shown. It can be seen that the degradation capacity of tetracycline hydrochloride by PMS and low-temperature plasma alone is limited. The degradation rate of tetracycline hydrochloride by PMS alone is 22.22%, and the degradation rate of tetracycline hydrochloride by low-temperature plasma alone is 57.21%. When PMS is combined with a low-temperature plasma device, the degradation rate of tetracycline hydrochloride gradually increases with the increase of PMS concentration. When the concentration of PMS increases from 0.1g / L to 0.5g / L, the degradation rate of tetracycline hydrochloride increases from 79.31% to 87.22%.

[0043] The treated wastewater solution from Example 3 to Example 5 was taken every 5 minutes, and the content of tetracycline hydrochloride was detected and analyzed using an ultraviolet spectrophotometer. The results are as follows: Figure 3It can be seen that with the increase of voltage, the degradation rate of tetracycline hydrochloride is also gradually increasing. When the voltage increases from 6.5kV to 8.5kV, the degradation rate of tetracycline hydrochloride increases from 81.82% to 91.62%.

[0044] The treated wastewater solution from Example 5 to Example 8 was taken every 5 minutes, and the content of tetracycline hydrochloride was detected and analyzed using an ultraviolet spectrophotometer. The results are as follows: Figure 4 It can be seen that with the increase of gas flow rate, the degradation of tetracycline hydrochloride first increases and then decreases, and when the air flow rate is 1L / min, the degradation rate of tetracycline hydrochloride is the highest, which can reach 91.62%.

[0045] The treated wastewater solution from Example 9 to Example 11 was taken every 5 minutes, and the content of tetracycline hydrochloride was detected and analyzed using an ultraviolet spectrophotometer. The results are as follows: Figure 5 As shown. It can be seen that when 0.05g / L Cu Ⅱ (copper sulfate pentahydrate), the degradation rate of tetracycline hydrochloride is the highest, reaching 94.08%.

[0046] The treated wastewater solution was taken from Example 12 to Example 14 and Example 10 every 5 minutes, and the content of tetracycline hydrochloride was detected and analyzed using a UV-spectrophotometer. The results are as follows: Figure 6 As shown. It can be seen that different working gases have different degradation abilities for tetracycline hydrochloride. When the working gas is oxygen, the degradation rate of tetracycline hydrochloride can be as high as 95.73%; when the working gas is air, the degradation rate of tetracycline hydrochloride is 94.08%; when the working gas is argon, the degradation rate of tetracycline hydrochloride is 87.74%; when the working gas is nitrogen, the degradation rate of tetracycline hydrochloride is only 82.53%. When the working gas is oxygen, the reactive oxygen species produced by the emission are the main factors affecting the degradation of tetracycline hydrochloride, among which hydroxyl radicals, sulfate radicals, ozone and hydrogen peroxide play a major role. When the working gas is air, a large amount of reactive nitrogen and nitrogen ions will be generated in the system. Since the oxidizing ability of reactive nitrogen is lower than that of reactive oxygen, the removal rate of tetracycline hydrochloride is reduced. In addition, the formation of reactive nitrogen consumes a certain amount of oxygen, resulting in a decrease in the amount of reactive oxygen in the system. When argon is used as the working gas, hydroxyl radicals, sulfate radicals and hydrogen peroxide are the main substances that degrade tetracycline hydrochloride. When the working gas is nitrogen, the degradation effect of tetracycline hydrochloride is the worst due to the high content of active nitrogen.

[0047] The treated wastewater solution was taken from Example 10, Example 15 and Example 6 every 5 minutes, and the content of tetracycline hydrochloride was detected and analyzed using a UV-spectrophotometer. The results are as follows: Figure 7 As shown. It can be seen that when 0.05g / L Cu Ⅱ(copper sulfate pentahydrate), the degradation rate of tetracycline hydrochloride was the highest, and the addition of Cu Ⅱ The degradation rate of tetracycline hydrochloride>adding Fe Ⅱ The degradation rate of tetracycline hydrochloride>addition of Mn Ⅱ Degradation rate of tetracycline hydrochloride.

[0048] The treated wastewater solution from Example 10 was analyzed using the capture agent DMPO (5,5-dimethyl-1-pyrroline-N-oxide). DMPO reacted with hydroxyl radicals and sulfate radicals to generate spin adducts DMPO-·OH and DMPO-·SO 4 - Then, the electron spin resonance technique was used to measure the generation of DMPO-·OH and DMPO-·SO in the system. 4 - The spectrum of Figure 8 shown. Figure 8 Shows the typical DMPO-·OH (1:2:2:1) and DMPO-·SO 4 - (1:1:1:1:1:1) signal, which shows that in the present invention, the plasma activates Cu Ⅱ -Hydroxy radicals and sulfate radicals exist in the PMS system.

[0049] In Examples 12 to 14 and 10, the concentration of the active substance in the system was detected by using an ELISA instrument and electron spin resonance technology. Fig. 9 As shown in Figure 2, it can be seen that the concentrations of active substances produced under different gas conditions are different, oxygen conditions > air conditions > argon conditions > nitrogen conditions. This result is consistent with Figure 6 The degradation rate of tetracycline hydrochloride under different gas conditions corresponds. Under oxygen conditions, the content of active substances is the highest, and the degradation rate of tetracycline hydrochloride is higher, which also shows that oxygen plasma can efficiently activate Cu Ⅱ -PMS system produces high concentration of free radicals, which in turn degrade new pollutants in water.

[0050] Fig.10It is a scavenger experiment, which is used to verify the active free radicals that play a major role in the system. Among them, tert-butanol specifically scavenges hydroxyl radicals, and ethanol is a scavenger of hydroxyl radicals and sulfate radicals. It can be seen that when 30mM tert-butanol is added, the degradation rate of tetracycline hydrochloride decreases by 22.29%, indicating that hydroxyl radicals play an important role in the degradation of tetracycline hydrochloride. In addition, the final degradation effects of adding 20mM tert-butanol and 30mM tert-butanol on tetracycline hydrochloride are similar, indicating that excessive tert-butanol cannot completely inhibit the degradation of tetracycline hydrochloride, and other active substances also play a role in the degradation of tetracycline hydrochloride. With the increase of ethanol concentration, the degradation rate of tetracycline hydrochloride shows a downward trend. When 30mM ethanol is used, the degradation rate of tetracycline hydrochloride is reduced by 38.03% within 20 minutes. Compared with the addition of tert-butanol, the inhibitory effect of adding ethanol at the same concentration on tetracycline hydrochloride is more significant, indicating that sulfate radicals also play an important role in the degradation of tetracycline hydrochloride.

[0051] The treated wastewater solution from Example 10 was taken every 5 minutes, and the absorbance of tetracycline hydrochloride in the wavelength range of 220 nm to 450 nm at different treatment times was measured using an ultraviolet spectrophotometer. Fig.11 As shown. It can be seen that two absorption peaks were observed in the spectrum in the corresponding curve before low-temperature plasma discharge treatment: one is located in the ultraviolet absorption region with a wavelength of around 275 nanometers, which is mainly related to the benzene ring and its connected hydroxyl and amide groups; the other is in the visible light absorption range with a wavelength of around 359 nanometers, which is mainly related to other benzene rings. As the treatment time increases, the characteristic absorption peak of tetracycline hydrochloride gradually decreases, which may be due to the oxidation of the hydroxyl, amide and enol in the aromatic ring on the benzene ring, and the removal of degradation intermediates similar to tetracycline hydrochloride, indicating that low-temperature plasma and Cu Ⅱ -PMS binding can effectively remove tetracycline hydrochloride.

[0052] In summary, plasma can efficiently activate Cu Ⅱ -PMS system produces high concentration of free radicals, which can effectively degrade new pollutants in water. Ⅱ -PMS system mainly involves Fenton-like reaction, Cu Ⅰ / Cu Ⅱ Cycle and oxygen-sulfur free radical cycle and a series of chain reactions. Among them, hydrogen peroxide and Cu generated by low-temperature plasma similar to Fenton reaction Ⅱ The reaction produces hydroxyl radicals, thereby increasing the concentration of hydroxyl radicals in the system; Cu Ⅰ / Cu ⅡCycling can accelerate electron transfer; low-temperature plasma can also activate PMS to produce sulfate radicals, introducing new active free radicals into the system, which can not only make full use of the various physical and chemical effects produced by low-temperature plasma, but also achieve efficient, continuous and multi-effect catalytic degradation of pollutant solutions.

[0053] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A plasma activated Cu Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The following steps are involved: Adding divalent copper salt and peroxymonosulfate to the wastewater to be treated containing pollutants to obtain a mixed wastewater solution; Continuously introducing working gas into the mixed wastewater solution to obtain a wastewater solution with uniform gas mixing; The wastewater solution with uniform gas mixture is introduced into low-temperature plasma, so that the active substances generated by the low-temperature plasma are fully in contact with the wastewater solution with uniform gas mixture, more hydroxyl radicals and sulfate radicals are generated, and at the same time, they act on pollutants together with other active substances generated by the low-temperature plasma to achieve the degradation of pollutants.

2. The plasma activated Cu according to claim 1 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The pollutant is one or more mixtures of β-lactams, macrolides, aminoglycosides, tetracyclines, lincomycins, chloramphenicols or polypeptide antibiotics.

3. The plasma activated Cu according to claim 2 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The concentration of the tetracycline antibiotics is 5 mg / L to 200 mg / L, and the concentration of the added peroxymonosulfate is 0.1 to 0.5 g / L.

4. The plasma activated Cu according to claim 1 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The concentration of the divalent copper salt is 0.005-0.1 g / L.

5. The plasma activated Cu according to claim 1 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The peroxymonosulfate is one or more mixtures of sodium persulfate or potassium persulfate.

6. The plasma activated Cu according to claim 1 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The working gas is oxygen, air, argon or nitrogen.

7. The plasma activated Cu according to claim 1 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The flow rate of the working gas is 0.2-5 L / min.

8. The plasma activated Cu according to claim 1 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The low-temperature plasma discharge device adopts a pulse power supply, and the voltage of the pulse power supply is 6.5~8.5kV.

9. The plasma activated Cu according to claim 1 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The time length of the low temperature plasma treatment gas-mixed wastewater solution is 0 to 20 minutes.

10. The plasma activated Cu according to claim 1 Ⅱ - A method for degrading new pollutants in water using a PMS system, characterized in that: The divalent copper salt may be replaced by iron or manganese ions.

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