A method of activating persulfate salts for degradation of organic contaminants

Abstract

The application discloses a method for activating persulfate to degrade organic pollutants, and comprises the following steps: adding tartaric acid, copper ions and persulfate with a molar concentration ratio of (10-100):(2-5):(50-100) into wastewater containing organic pollutants to be degraded, so as to degrade the organic pollutants in the wastewater; wherein the tartaric acid is used to form a tartaric acid-copper complex with the copper ions, and the tartaric acid-copper complex is used to activate the persulfate. The tartaric acid-copper complex activates the persulfate, the copper in the tartaric acid-copper complex can effectively react with the persulfate under acidic or neutral conditions, and continuously generates highly active trivalent copper to degrade the organic pollutants, so that the activation efficiency of the persulfate and the utilization rate of the copper ions are improved, and the organic pollutants in the wastewater are efficiently degraded.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water organic pollutant treatment, and particularly relates to a method for degrading organic pollutants by activating peroxymonosulfate. BACKGROUND

[0002] With the continuous improvement of people's living standards, more and more organic pollutants are found in water bodies, which have caused great harm to human health and the ecological environment. However, the traditional process of sewage treatment plants cannot effectively remove them, so they are continuously released into the environment. Therefore, it is necessary to use advanced oxidation technology to effectively remove them. Among the many advanced oxidation technologies, the peroxymonosulfate-based advanced oxidation technology has attracted much attention because it can activate selective active substances.

[0003] Peroxymonosulfate (PMS) is a common, low-cost and environmentally friendly water treatment oxidant, and has the advantages of good oxidation, safe use, easy control, easy transportation and storage compared with other oxidants including hydrogen peroxide, ozone, chlorine and chlorine dioxide. The principle of degrading organic matter is that peroxymonosulfate is activated by a specific method to generate high oxidation-reduction potential sulfate radicals and hydroxyl radicals, and the generated sulfate radicals and hydroxyl radicals oxidize and degrade organic matter, thereby achieving the purpose of removing organic matter. As a highly efficient and stable oxidant, PMS can be activated by non-radical pathways in addition to the generation of sulfate radicals and hydroxyl radicals by the radical pathway. At present, PMS can be activated by ultrasound, photolysis, heating, excessive metals, heterogeneous catalysts and organic catalysts, but most of the PMS activation methods are through the radical pathway; in addition, peroxymonosulfate is more easily activated under alkaline conditions because of its unstable form under alkaline conditions. Therefore, it is necessary to find a method for activating PMS based on non-radical pathways under acidic and neutral conditions.

[0004] The activation of peroxymonosulfate refers to the production of active substances by peroxymonosulfate (PMS) through a certain means, and the oxidation of the active substances is much stronger than that of PMS, and the active substances are used for degrading organic pollutants.

[0005] Among the transition metal activation technologies, copper-based persulfate technology has attracted the attention of scholars due to its wide pH adaptation range and other advantages. Moreover, compared with iron, cobalt and other metals, the allowable concentration of copper ions in water is higher (the concentration limit of copper ions is less than 1.0 mg / L, the concentration limit of iron ions is not higher than 0.3 mg / L, and the concentration limit of cobalt ions is not higher than 0.02 mg / L). Therefore, the activation of persulfate based on copper ions has more advantages than iron and cobalt. However, in the process of copper-activated persulfate, the reaction of persulfate is extremely slow under acidic and neutral conditions, which leads to the difficulty of quickly removing organic pollutants.

[0006] In view of the above technical problems, a patent in the prior art activates persulfate by copper ion-strengthened hydroxylamine, which can quickly generate trivalent copper and effectively remove organic pollutants. In another patent, hydroxylamine, persulfate, copper ions and iron ions are added to the water to be treated, which has the characteristics of fast free radical generation and high efficiency of organic pollutant removal. However, the above patents all use free radicals to degrade organic pollutants, so the removal of organic pollutants is not selective and targeted.

[0007] Considering that the copper-activated persulfate method in the prior art cannot meet our needs, the technical problem that needs to be urgently solved by those skilled in the art at present is that in the process of copper-activated persulfate, the reaction of persulfate is extremely slow under acidic and neutral conditions, which leads to the difficulty of quickly removing organic pollutants. SUMMARY

[0008] To solve the above problems, the present application provides a method for degrading organic pollutants by activating persulfate, comprising:

[0009] Tartaric acid, copper ions and persulfate with a molar concentration ratio of (10-100):(2-5):(50-100) are added to wastewater containing organic pollutants to be degraded to degrade the organic pollutants in the wastewater; wherein the tartaric acid is used to form a tartaric acid-copper complex with copper ions, and the tartaric acid-copper complex is used to activate the persulfate.

[0010] Preferably, the molar concentration ratio of the organic pollutants, the tartaric acid, the copper ions and the persulfate is 1:20:5:100.

[0011] Preferably, the copper ions are divalent copper ions.

[0012] Preferably, the tartaric acid-copper complex reacts with the persulfate to generate trivalent copper.

[0013] Preferably, the tartaric acid is at least one of DL-tartaric acid, L-tartaric acid, D-tartaric acid, ammonium tartrate, potassium bitartrate, ammonium bitartrate, potassium tartrate, sodium tartrate, potassium sodium tartrate.

[0014] Preferably, the copper ion donor is at least one of copper sulfate, copper nitrate, copper chloride, copper perchlorate.

[0015] Preferably, the tartaric acid and the copper ion donor are tartaric acid-copper wastewater.

[0016] Preferably, the persulfate salt donor is potassium monopersulfate.

[0017] Preferably, the pH of the wastewater containing organic pollutants is 3.0-10.0.

[0018] Preferably, the pH of the wastewater containing organic pollutants is 3.6-7.0.

[0019] Compared with the prior art, the present application has the following advantages:

[0020] The application discloses a method for activating persulfate salt to degrade organic pollutants, comprising the following steps: adding tartaric acid, copper ions and persulfate salt with a molar concentration ratio of (10-100):(2-5):(50-100) into wastewater containing organic pollutants to be degraded, so as to degrade the organic pollutants in the wastewater; wherein the tartaric acid is used to form a tartaric acid-copper complex with the copper ions, and the tartaric acid-copper complex is used to activate the persulfate salt. The application activates the persulfate salt through the tartaric acid-copper complex, and the copper in the tartaric acid-copper complex can effectively react with the persulfate salt under acidic or neutral conditions, thereby continuously generating highly active trivalent copper to degrade the organic pollutants, improving the activation efficiency of the persulfate salt and the utilization rate of the copper ions, and efficiently degrading the organic pollutants in the wastewater.

[0021] The application accelerates the circulation of copper ions by adding tartaric acid, promotes the circulation rate of copper ions (Cu (II) / Cu (I) or Cu (II) / Cu (III)), thereby strengthening the circulation of copper ions in the formed tartaric acid-copper complex system, allowing tartaric acid and copper ions to be complexed to form divalent copper and peroxymonosulfate in a tartaric acid complex state, and effectively reacting with peroxymonosulfate to continuously and quickly produce highly active trivalent copper to degrade organic pollutants, further strengthening the activation of peroxymonosulfate, improving the activation efficiency of peroxymonosulfate and the utilization rate of copper ions, thereby efficiently removing organic pollutants in wastewater to be degraded, and to a certain extent, overcoming the utilization efficiency problem of copper ions in the copper-activated peroxymonosulfate system. In addition, the removal of organic pollutants in the application is a non-radical degradation process, which produces selective active substances, so the removal of organic pollutants is selective and targeted, and only specific organic pollutants are degraded faster.

[0022] In addition, the application can be smoothly carried out at room temperature, and without additional energy injection such as additional aeration, illumination, ultrasonic and the like, the efficient removal of organic pollutants can be realized in a wide pH range, and the tartaric acid and copper ions used in the application can be derived from copper tartrate wastewater, so as to achieve the purpose of "waste treatment with waste". BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 TA / Cu 2+ / PMS system compared with different blank systems on the degradation effect curve of benzoic acid;

[0024] Figure 2 TA / Cu 2+ / PMS system for degrading benzoic acid;

[0025] Figure 3 TA / Cu 2+ / PMS system on different organic pollutants;

[0026] Figure 4 TA / Cu 2+ / PMS system for degrading benzoic acid. DETAILED DESCRIPTION

[0027] The application will be further described in detail below with reference to the accompanying drawings and specific embodiments, but should not be understood as limiting the application. If not specifically indicated, the technical means used in the embodiments are conventional means familiar to those skilled in the art. Unless specifically indicated, the examples, methods and devices used in the application are conventional reagents, methods and devices in the technical field.

[0028] Two copper cycles are involved in the process of copper-activated persulfate: (1)

[0029] Cu(II)→Cu(I)→Cu(III)→Cu(II): Cu(II) reacts with persulfate to generate Cu(I), Cu(I) reacts with PMS to generate Cu(III), and Cu(III) is converted into Cu(II) after oxidizing organic pollutants; (2) Cu(II)→Cu(III)→Cu(II): Cu(II) directly reacts with PMS to generate Cu(III), and Cu(III) is converted into Cu(II) after oxidizing organic pollutants, forming a cycle of Cu(II)→Cu(III)→Cu(II).

[0030] To solve the problem that in the process of copper-activated persulfate, due to the low activation efficiency of persulfate and the low utilization rate of copper ions, almost no active substance trivalent copper is produced, and thus the reaction between copper ions and persulfate is extremely slow (the activation efficiency of persulfate is low) under acidic and neutral conditions, resulting in almost no degradation of organic pollutants, the technical concept proposed by the application is that tartaric acid is added to promote the cycle rate of copper ions (Cu(II) / Cu(I) or Cu(II) / Cu(III)), thereby improving the activation efficiency of persulfate and the utilization rate of copper ions and efficiently improving the efficiency of degrading organic pollutants.

[0031] Based on the above technical concept, the specific embodiments of the application are as follows:

[0032] The application provides a method for degrading organic pollutants by activating persulfate, comprising:

[0033] Tartaric acid, copper ions and persulfate with a molar concentration ratio of (10-100):(2-5):(50-100) are added to wastewater containing organic pollutants to be degraded to degrade the organic pollutants in the wastewater; wherein the tartaric acid is used to form a tartaric acid-copper complex with the copper ions, and the tartaric acid-copper complex is used to activate the persulfate.

[0034] The molar concentration ratio of the organic pollutants, the tartaric acid, the copper ions and the persulfate is 1:(10-100):(2-5):(50-100).

[0035] The wastewater containing organic pollutants needs to be adjusted to pH 3.0-10.0 by a pH regulator to obtain the wastewater containing organic pollutants to be degraded. The pH value of the water sample is in the range of 3.0-10.0, and the degradation efficiency of the organic pollutants is considerable, and the degradation time is within 15 minutes. The pH regulator is selected from common pH regulators, which can be any one of perchloric acid, sulfuric acid, hydrochloric acid, nitric acid, sodium hydroxide, potassium hydroxide, calcium hydroxide, boric acid, sodium tetraborate and potassium tetraborate. Specifically, the pH regulator can be further preferably sulfuric acid and sodium hydroxide.

[0036] In the embodiment of the present application, tartaric acid is used to realize the complexation of copper ions, generate a tartaric acid-copper complex, and activate the peroxymonosulfate in the complex state of the tartaric acid in the complex to generate a reactive substance, trivalent copper, to degrade (oxidize) organic pollutants. The highly active trivalent copper is quickly degraded into divalent copper after degrading the organic pollutants, and the generated divalent copper can continue to react and degrade, thus forming a cycle of Cu(II)(→Cu(I))→Cu(III)→Cu(II).

[0037] The complexing agent (tartaric acid TA) added in the application changes the degradation mechanism of active substances and organic matter in the system. Compared with the existing copper-activated persulfate technology, on the one hand, the active substance generated in the method is different from the free radical generated in other methods of copper-activated persulfate under acidic and neutral conditions. The active substance generated in the method is a tartaric acid complex state of trivalent copper. The copper ion activation of PMS is improved by the tartaric acid-copper complex system: the addition of tartaric acid accelerates the circulation of copper ions, promotes the circulation rate of copper ions (Cu(II) / Cu(I) or Cu(II) / Cu(III)), continuously generates highly active trivalent copper to degrade organic pollutants in the circulation process, strengthens the circulation of copper ions in the tartaric acid-copper complex system, makes copper ions effectively react with per monosulfate under acidic or neutral conditions, further strengthens the activation of per monosulfate, improves the activation efficiency of per monosulfate and the utilization rate of copper ions, thereby effectively improving the efficiency of degrading organic pollutants, efficiently (within 15 minutes) removing organic pollutants in the wastewater to be degraded, and to some extent overcoming the problem of the utilization efficiency of copper ions in the copper-activated per monosulfate system; on the other hand, the degradation mechanism changes from the original free radical process to a non-free radical process. The degradation mechanism of the application is different from the free radical process (the free radical process will react with various organic matters, and the natural organic matter in water will affect the degradation of specific organic matter). The active substance generated in the application is different from the conventional Fenton system and Fenton-like system (i.e., H2O2 system, which can oxidize various organic matters). The removal of organic pollutants in the application is a non-free radical degradation process. The process generates selective active substances, so the removal of organic pollutants has selectivity and pertinence, and only specific organic pollutants are degraded faster.

[0038] The corresponding reaction equation involved in the degradation process of the application is as follows:

[0039] Cu 2+ +TA→Cu(II)-TA

[0040]

[0041]

[0042] Cu(III)-TA+pollutant→oxidation product

[0043] Further, the difference between the conventional degradation mechanism (free radical process) and the degradation mechanism of the present application (non-free radical process) is explained as follows: in the conventional Fenton system and Fenton-like system, since the metal in the solution (such as copper, iron, cobalt, etc.) is often in the form of ion state rather than complex state, the metal ion will directly generate free radicals by single electron transfer reaction with oxidants (such as persulfate, etc.), and the organic pollutants are removed by free radicals; in the present application, the metal exists in the form of complex, so under the influence of the complex, multi-electron transfer reaction often occurs to directly generate high-valence metal complexes (such as Cu(III)-tartaric acid complex in the present application) with oxidation characteristics, and the organic pollutants are selectively and specifically removed by the metal complex.

[0044] The present application can be carried out smoothly at room temperature, and the efficient removal of organic pollutants can be achieved in a wide pH range without additional energy injection such as aeration, illumination, ultrasonic, etc. The tartaric acid and copper ions used in the present application can be derived from copper tartrate wastewater, so as to achieve the purpose of "waste treatment with waste". In addition, the method provided by the present application has low cost, high degradation efficiency, simple operation and good application prospect in water body pollutant remediation and wastewater treatment.

[0045] In the present application, by sequentially adding tartaric acid, copper ions and peroxymonosulfate into the wastewater containing organic pollutants, and stirring for 10-60 min at room temperature, the degradation time is changed from several hours or basically no degradation to 15 min, and the organic pollutants can be basically degraded within 15 min.

[0046] The organic pollutants in the wastewater of the present application are antibiotics, drugs and personal care products, etc. It should be noted that the concentration of the organic pollutants provided in the specific embodiments of the present application is 5 μmol / L, but high concentration of organic pollutants can also use the method provided by the present application (20-50 μmol / L), and the concentration of the organic pollutants is not limited here.

[0047] Preferably, the molar concentration ratio of the organic pollutants, the tartaric acid, the copper ions and the peroxymonosulfate is 1:20:5:100.

[0048] The molar concentration ratio of the organic pollutants, tartaric acid, copper ions and peroxymonosulfate in the present application is preferably 1:20:5:100, and under this molar concentration ratio, the removal rate of the organic degradation substance, benzoic acid, is as high as 99.9%. If the water body to be treated with naproxen and ibuprofen as the organic pollutants is to be degraded, the molar concentration ratio of benzoic acid, tartaric acid, copper sulfate and peroxymonosulfate is preferably 1:100:4:100, and under this molar concentration ratio, the removal rate of the organic degradation substance (naproxen and ibuprofen) is as high as 85%.

[0049] Preferably, the copper ions are divalent copper ions.

[0050] Preferably, the tartaric acid-copper complex reacts with the peroxymonosulfate to generate trivalent copper.

[0051] The active substance in the present application is used to degrade organic pollutants, and in the process of copper-activated peroxymonosulfate, the generated active substance is Cu 3+ , Cu 3+ is generated by the electron transfer reaction (redox reaction) of peroxymonosulfate and copper ions, so the active substance (having oxidizing ability to oxidize organic pollutants) generated by the activation of peroxymonosulfate is trivalent copper, and the oxidizing ability of the active substance is much stronger than that of peroxymonosulfate.

[0052] In the present application, tartaric acid does not directly react with copper ions, but forms a tartaric acid-copper complex, and the complex state of divalent copper in the complex reacts with peroxymonosulfate to generate an active substance, highly active trivalent copper (both Cu cycles eventually generate this active substance), which degrades (oxidizes) organic pollutants. When the generated active substance, trivalent copper, rapidly degrades (oxidizes) the organic pollutants, it becomes divalent copper, which continues to react and degrade, thereby entering the cycle of Cu(II)→Cu(III)→Cu(II).

[0053] It should be noted that the trivalent copper in the embodiments of the present application is different from the general Cu 3+ (for example, hydroxylamine reduces Cu 2+ to Cu + , and then PMS and percarbonate are used to oxidize Cu + to Cu 3+ , and the generated Cu 3+ is Cu 3+), but is obtained by the reaction of a persulfate and a complex of copper tartrate, and is trivalent copper (Cu(III)) in the copper tartrate complex system, that is, also includes trivalent copper in the tartrate complex state. Thus, it is a complex cycle throughout the copper cycle, and further, the cycle of copper ions is accelerated in the activation process, the cycle rate of copper ions (Cu(II) / Cu(I) or Cu(II) / Cu(III)) is promoted, and highly active trivalent copper is continuously generated to degrade organic pollutants, thereby improving the activation efficiency of the persulfate and the utilization rate of copper ions, and efficiently degrading organic pollutants in wastewater.

[0054] Preferably, the tartrate is at least one of DL-tartaric acid, L-tartaric acid, D-tartaric acid, ammonium tartrate, potassium hydrogen tartrate, ammonium hydrogen tartrate, potassium tartrate, sodium tartrate, and potassium sodium tartrate.

[0055] In the present application, the tartrate does not react with copper ions, but is complexed with copper as a complexing agent to form a complex, thereby strengthening the cycle of copper, and has no toxicity and does not cause secondary pollution to the water body to be treated.

[0056] In the present application, the cycle rate of copper ions is accelerated due to the addition of the tartrate, thereby strengthening the cycle of copper ions in the copper tartrate complex system, allowing copper ions to effectively react with the persulfate under acidic or neutral conditions, and thus improving the activation efficiency of the persulfate and the utilization rate of copper ions.

[0057] In the present application, the tartrate can be further preferably potassium sodium tartrate.

[0058] Preferably, the copper ion donor is at least one of copper sulfate, copper nitrate, copper chloride, and copper perchlorate.

[0059] In the present application, the copper ion donor can be further preferably copper sulfate.

[0060] Preferably, the tartrate and the copper ion donor are copper tartrate wastewater.

[0061] In the present application, the tartrate can be DL-tartaric acid, L-tartaric acid, D-tartaric acid, etc., and the copper ion donor can be copper sulfate, copper nitrate, copper chloride, etc. In addition to the above-listed tartrates and copper ion donors, the tartrate and the copper ion donor can also be selected as copper tartrate wastewater. Since the copper tartrate complex is relatively common in circuit wastewater, the waste can be directly utilized, that is, the copper tartrate wastewater is used as the tartrate and the copper ion donor, thereby achieving the purposes of "waste treatment with waste" and cost reduction.

[0062] Preferably, the persulfate donor is potassium hydrogen persulfate.

[0063] Preferably, the pH of the wastewater containing the organic pollutants is 3.0-10.0.

[0064] Preferably, the pH of the wastewater containing the organic pollutants is 3.6-7.0.

[0065] In particular implementation, adjusting the pH of the wastewater to 3.6-7.0 can further improve the degradation efficiency. Through experiments, it is found that the degradation efficiency of benzoic acid is more than 90% under the condition of pH 3.6-7.0, which further proves that the tartaric acid / copper ion / persulfate system has better degradation effect under the pH in the range of 3.6-7.0.

[0066] In order for those skilled in the art to better understand the present application, the method for degrading organic pollutants by activating persulfate provided by the present application is described below through multiple specific examples.

[0067] Example 1

[0068] Take the water body to be treated containing the organic pollutant benzoic acid, and the pH of the water body is in the range of 3-10, so there is no need to adjust the pH.

[0069] Tartaric acid (TA), copper sulfate (as a donor of copper ions), and persulfate (PMS) are sequentially added to the water body to be degraded, and there is no need to adjust the water temperature. Under the condition of room temperature, the reaction is completed after 15 minutes of uniform stirring. At this time, the molar concentration ratio of benzoic acid, tartaric acid, copper sulfate, and persulfate is 1:20:4:100, and the pH of the water sample is 3.60.

[0070] In this example, the degradation effect of benzoic acid by the TA / Cu Figure 1 , Figure 1 TA / Cu 2+ / PMS system of Example 1 of the present application is compared with different blank systems. As can be seen from Figure 1 , compared with the tartaric acid / copper ion / persulfate system, the degradation effect of benzoic acid by the system without adding tartaric acid, copper ions, or persulfate is almost zero. With the extension of time, the residual concentration of benzoic acid in the tartaric acid / copper ion / persulfate system is lower and lower, and after 15 minutes, the remaining benzoic acid in the system is 5%. This shows that the tartaric acid / copper ion / persulfate system has excellent removal effect on benzoic acid.

[0071] Example 2

[0072] The initial pH of the water body to be treated containing the organic pollutant benzoic acid is adjusted to 3.6-7.0 by using sulfuric acid and sodium hydroxide (two different pH adjusters) respectively.

[0073] Tartaric acid, copper sulfate (as a copper ion donor), and persulfate were added sequentially to two types of water to be degraded. No temperature adjustment was required; the reaction was carried out at room temperature with uniform stirring for 15 minutes. At this point, the molar ratio of benzoic acid, tartaric acid, copper sulfate, and persulfate was 1:20:4:100.

[0074] In this embodiment, refer to Figure 2 , Figure 2 This is a graph showing the effect of the tartaric acid / copper ion / persulfate system on the degradation of benzoic acid in Example 2 of the present invention at different initial pH values ​​of water samples (under pH conditions of 3.6 to 7.0). Figure 2 As can be seen, the degradation efficiency of benzoic acid exceeds 90% under pH conditions of 3.6–7.0. This indicates that the tartaric acid / copper ion / persulfate system has a wide applicable pH range, and also shows that the degradation effect is better when the pH is in the range of 3.6–7.0.

[0075] Example 3

[0076] Water samples containing naproxen and ibuprofen as organic pollutants were collected from the water body to be treated.

[0077] Tartaric acid, copper sulfate (as a copper ion donor), and persulfate were added sequentially to the water to be degraded. No temperature adjustment was required; the reaction was carried out at room temperature with uniform stirring for 15 minutes. At this point, the molar ratio of benzoic acid, tartaric acid, copper sulfate, and persulfate was 1:100:4:100, and the pH of the water sample was 3.60.

[0078] In this embodiment, refer to Figure 3 , Figure 3 Example 3 of the present invention is based on TA / Cu 2+ Degradation effects of different organic pollutants (naproxen and ibuprofen) on the PMS system. (From...) Figure 3 The results show that the degradation efficiency of naproxen and ibuprofen is both above 85%, indicating that the tartaric acid / copper ion / persulfate system has high universality for the degradation of organic pollutants.

[0079] The following set of embodiments will further illustrate the solution of this patent in detail.

[0080] Example 4

[0081] The water body to be treated, with benzoic acid as the main organic pollutant, has a pH range of 3 to 10, so there is no need to adjust the pH.

[0082] TA, copper sulfate (as a donor of copper ions) and PMS were added into the water body to be degraded in sequence, without adjusting the water temperature, and the reaction was completed under the condition of uniform stirring at room temperature for 15 min. At this time, the molar concentration ratio of benzoic acid, tartaric acid, copper sulfate and persulfate was 1:20:2:100, and the pH of the water sample was 3.60.

[0083] In this embodiment, reference is made to Figure 4 , Figure 4 TA / Cu 2+ / PMS with different molar concentration ratios in Examples 4-9 of the present application for the degradation of benzoic acid, wherein Condition 1 is the experimental condition of Example 4. It can be seen from Figure 4 that the degradation rate of benzoic acid in the tartaric acid / copper ion / persulfate system is more than 75% under this molar concentration ratio, and the removal rate of benzoic acid, an organic pollutant, is 86% under the specific molar concentration ratio of Example 4 (Condition 1), indicating that the tartaric acid / copper ion / persulfate system has degradation ability for benzoic acid within the concentration range of the claim.

[0084] Example 5

[0085] The water body to be treated with the organic pollutant being benzoic acid has a pH in the range of 3-10, and thus the pH does not need to be adjusted.

[0086] TA, copper sulfate (as a donor of copper ions) and PMS were added into the water body to be degraded in sequence, without adjusting the water temperature, and the reaction was completed under the condition of uniform stirring at room temperature for 15 min. At this time, the molar concentration ratio of benzoic acid, tartaric acid, copper sulfate and persulfate was 1:20:5:100, and the pH of the water sample was 3.60.

[0087] In this embodiment, reference is made to Figure 4 , Figure 4 TA / Cu 2+ / PMS with different molar concentration ratios in Examples 4-9 of the present application for the degradation of benzoic acid, wherein Condition 2 is the experimental condition of Example 5. It can be seen from Figure 4 that the degradation rate of benzoic acid in the tartaric acid / copper ion / persulfate system is more than 75% under this molar concentration ratio, and the removal rate of benzoic acid, an organic pollutant, is 99.9% under the specific molar concentration ratio of Example 5 (Condition 2), indicating that the tartaric acid / copper ion / persulfate system has degradation ability for benzoic acid within the concentration range of the claim.

[0088] Example 6

[0089] Take the organic pollutants as benzoic acid to be treated water body, the water body pH is in 3~10 range, therefore need not to adjust pH.

[0090] To be degraded water body in turn add tartaric acid (TA), copper sulfate (as a donor of copper ions) and peroxymonosulfate (PMS), without adjusting water temperature, under room temperature conditions, uniform stirring reaction 15 min, that is completed. At this time, the molar concentration ratio of benzoic acid, tartaric acid, copper sulfate and peroxymonosulfate is 1:10:4:100, and the pH of water sample is 3.60.

[0091] In this embodiment, refer to Figure 4 , Figure 4 TA / Cu 2+ / PMS of different molar concentration ratios in examples 4-9 of the application degrade benzoic acid. The effect comparison chart is shown in Figure 1. Condition 3 is the experimental condition of example 6. From Figure 1, it can be seen that under the molar concentration ratio, the degradation rate of benzoic acid in the tartaric acid / copper ion / peroxymonosulfate system is more than 75%, and under the specific molar concentration ratio of example 6 (condition 3), the removal rate of benzoic acid, an organic pollutant, is 77%, which indicates that the tartaric acid / copper ion / peroxymonosulfate system has degradation ability to benzoic acid within the concentration range of the claim. Figure 4 Example 7

[0092] Take the organic pollutants as benzoic acid to be treated water body, the water body pH is in 3~10 range, therefore need not to adjust pH.

[0093] To be degraded water body in turn add tartaric acid (TA), copper sulfate (as a donor of copper ions) and peroxymonosulfate (PMS), without adjusting water temperature, under room temperature conditions, uniform stirring reaction 15 min, that is completed. At this time, the molar concentration ratio of benzoic acid, tartaric acid, copper sulfate and peroxymonosulfate is 1:100:4:100, and the pH of water sample is 3.60.

[0094] In this embodiment, refer to

[0095] , Figure 4 TA / Cu 2+ / PMS of different molar concentration ratios in examples 4-9 of the application degrade benzoic acid. The effect comparison chart is shown in Figure 1. Condition 4 is the experimental condition of example 7. From Figure 1, it can be seen that under the molar concentration ratio, the degradation rate of benzoic acid in the tartaric acid / copper ion / peroxymonosulfate system is more than 75%, and under the specific molar concentration ratio of example 7 (condition 4), the removal rate of benzoic acid, an organic pollutant, is 81%, which indicates that the tartaric acid / copper ion / peroxymonosulfate system has degradation ability to benzoic acid within the concentration range of the claim. Figure 4 Figure 4 Example 7

[0096] ​Example 8

[0097] The water body to be treated has an organic pollutant of benzoic acid, and the pH of the water body is in the range of 3-10, so there is no need to adjust the pH.

[0098] Tartaric acid (TA), copper sulfate (as a donor of copper ions), and persulfate (PMS) are sequentially added to the water body to be degraded, without adjusting the water temperature, and the reaction is completed under room temperature conditions with uniform stirring for 15 min. At this time, the molar concentration ratio of benzoic acid, tartaric acid, copper sulfate, and persulfate is 1:20:4:50, and the pH of the water sample is 3.60.

[0099] In this example, reference is made to Figure 4 , Figure 4 The effect comparison chart of TA / Cu 2+ / PMS with different molar concentration ratios in Examples 4-9 of the present application degrading benzoic acid, wherein condition 5 is the experimental condition of Example 8. As can be seen from Figure 4 , under this molar concentration ratio, the degradation rate of benzoic acid in the tartaric acid / copper ion / persulfate system is more than 75%, and under the specific molar concentration ratio of Example 8 (condition 5), the removal rate of benzoic acid, this organic pollutant, is 96%, indicating that the tartaric acid / copper ion / persulfate system has degradation capability for benzoic acid within the concentration range of the claim.

[0100] Example 9

[0101] The water body to be treated has an organic pollutant of benzoic acid, and the pH of the water body is in the range of 3-10, so there is no need to adjust the pH.

[0102] Tartaric acid (TA), copper sulfate (as a donor of copper ions), and persulfate (PMS) are sequentially added to the water body to be degraded, without adjusting the water temperature, and the reaction is completed under room temperature conditions with uniform stirring for 15 min. At this time, the molar concentration ratio of benzoic acid, tartaric acid, copper sulfate, and persulfate is 1:20:4:100, and the pH of the water sample is 3.60.

[0103] In this example, reference is made to Figure 4 , Figure 4 The effect comparison chart of TA / Cu 2+ / PMS with different molar concentration ratios in Examples 4-9 of the present application degrading benzoic acid, wherein condition 6 is the experimental condition of Example 9. As can be seen from Figure 4 , under this molar concentration ratio, the degradation rate of benzoic acid in the tartaric acid / copper ion / persulfate system is more than 75%, and under the specific molar concentration ratio of Example 9 (condition 6), the removal rate of benzoic acid, this organic pollutant, is 90%, indicating that the tartaric acid / copper ion / persulfate system has degradation capability for benzoic acid within the concentration range of the claim.

[0104] from ​ It can be seen that when the molar concentration ratio of organic pollutants, tartaric acid, copper ions and persulfate is 1:20:5:100, the removal rate of benzoic acid (organic degradation product) is the highest, reaching 99.9%.

[0105] For the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, as some steps can be performed in other orders or simultaneously according to the present invention. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and components involved are not necessarily essential to the present invention.

[0106] The above provides a detailed description of a method for degrading organic pollutants using activated persulfate. Specific examples have been used to illustrate the principles and implementation methods of the invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the invention. At the same time, those skilled in the art will recognize that, based on the ideas of the invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the invention.

Claims

1. A method for activating persulfate to degrade organic pollutants, characterized in that, include: Tartaric acid, copper ions, and persulfate in a molar concentration ratio of (10-100):(2-5):(50-100) are added to the wastewater containing organic pollutants to be degraded, thereby degrading the organic pollutants in the wastewater; wherein, the tartaric acid is used to form a tartaric acid-copper complex with copper ions, and the tartaric acid-copper complex is used to activate the persulfate. The copper ions are divalent copper ions; The tartaric acid-copper complex reacts with the persulfate to generate trivalent copper.

2. The method according to claim 1, characterized in that, The molar concentration ratio of the organic pollutant, the tartaric acid, the copper ions, and the persulfate is 1:20:5:

100.

3. The method according to claim 1, characterized in that, The tartaric acid is at least one of DL-tartaric acid, L-tartaric acid, D-tartaric acid, ammonium tartrate, potassium hydrogen tartrate, ammonium hydrogen tartrate, potassium tartrate, sodium tartrate, and sodium potassium tartrate.

4. The method according to claim 1, characterized in that, The copper ion donor is at least one of copper sulfate, copper nitrate, copper chloride, and copper perchlorate.

5. The method according to claim 1, characterized in that, The donors of tartaric acid and copper ions are tartaric acid-copper wastewater.

6. The method according to claim 1, characterized in that, The donor for the persulfate is potassium persulfate.

7. The method according to claim 1, characterized in that, The pH value of the wastewater containing organic pollutants is 3.0 to 10.

0.

8. The method according to claim 1, characterized in that, The pH value of the wastewater containing organic pollutants is 3.6 to 7.0.

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