Method for removing organic pollutants by promoting activation of peroxydisulfate

Abstract

The invention discloses a method for accelerating pollutant degradation by promoting activation of peroxymonosulfate (PMS), which comprises the following steps: adding sodium acetate into wastewater containing organic pollutants, uniformly mixing, adding the peroxymonosulfate and starting pollutant degradation, and the addition amount of the sodium acetate is less than or equal to 50 mmol / L. The activation mode of the peroxydisulfate comprises one or more of heterogeneous catalytic activation, homogeneous catalytic activation, thermal activation, ultraviolet activation and the like. Results show that by adding sodium acetate, the reaction can be obviously accelerated, and the pollutant degradation efficiency is greatly improved. The method has the characteristics of high reaction efficiency, low cost, environment friendliness and the like, and is suitable for efficiently removing organic pollutants in the water body.

Description

Technical Field

[0001] The present invention relates to a method for promoting the activation of peroxysulfate to remove organic pollutants, belonging to the technical field of organic wastewater treatment. Background Art

[0002] With the rapid development of global industrialization, urbanization, and agricultural modernization, the treatment of refractory organic pollutants (such as antibiotics, dyes, pesticides, etc.) in water bodies has become an important challenge in the environmental field. These organic pollutants have characteristics such as biological toxicity, environmental persistence, and bioaccumulation. Even at extremely low concentrations in water bodies, they can be transmitted through the food chain and bioaccumulated, posing a potential threat to ecological safety and human health. As one of the advanced oxidations, peroxysulfate can generate various reactive oxygen species (SO4•, •OH, 1 O2, O2• - ) to efficiently remove organic pollutants in water bodies. However, at present, various methods for activating peroxysulfate to degrade organic pollutants in water bodies all face the problem of low activation efficiency, resulting in unsatisfactory pollutant degradation effects; at the same time, some methods for enhancing activation performance require the introduction of a large amount of external energy or the addition of more catalysts and chemical reagents, increasing the treatment cost and the risk of secondary pollution. Therefore, there is an urgent need to develop an economical, efficient, and environmentally friendly peroxysulfate activation strategy. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for promoting the activation of peroxysulfate to remove organic pollutants. It aims to significantly improve the conversion efficiency of peroxysulfate under various activation methods such as heterogeneous catalytic activation, homogeneous catalytic activation, thermal activation, and ultraviolet light activation through low-cost and non-toxic chemical additives, and improve the degradation efficiency of pollutants in wastewater.

[0004] The technical solution of the present invention: A method for promoting the activation of peroxysulfate to remove organic pollutants, using sodium acetate as an additive to enhance the effect of peroxysulfate activation in degrading water body pollutants, wherein the addition amount of sodium acetate ≤ 50 mmol / L.

[0005] In the aforementioned method for promoting the activation of peroxysulfate to remove organic pollutants, the method specifically is to add peroxysulfate and sodium acetate to the wastewater containing organic pollutants, and activate peroxysulfate by different activation methods; wherein, the activation methods are one or more of heterogeneous catalytic activation, homogeneous catalytic activation, thermal activation, and photoactivation.

[0006] In the aforementioned method for promoting the activation of persulfate to remove organic pollutants, when the activation method is heterogeneous catalyst activation, the catalyst used is a metal oxide or sulfide, the metal ion is one or more of the transition metals cobalt, iron, manganese, and copper, and the dosage is 50-200 mg / L.

[0007] In the aforementioned method for promoting the activation of persulfate to remove organic pollutants, when the activation method is homogeneous catalytic activation, the catalyst used is a soluble metal salt, the metal ion is one or more of the transition metals cobalt, iron, manganese, and copper, and the dosage is 0.5-5 mmol / L.

[0008] In the aforementioned method for promoting the activation of persulfate to remove organic pollutants, when the activation method is thermal activation, the reaction temperature is from room temperature to 60 °C.

[0009] In the aforementioned method for promoting the activation of persulfate to remove organic pollutants, when the activation method is photoactivation, the light is ultraviolet light.

[0010] In the aforementioned method for promoting the activation of persulfate to remove organic pollutants, the organic pollutants include one or more of refractory organic pollutants such as antibiotics, dyes, and pesticides.

[0011] Advantages of the present invention: In recent years, the role of organic additives in the activation of persulfate has gradually attracted attention. Research shows that certain carboxylates (such as picolinic acid, cysteine, etc.) can improve the activation efficiency through mechanisms such as metal complexation or electron transfer promotion. And sodium acetate (NaAc), as a common inexpensive and non-toxic chemical and microbial carbon source, its strengthening effect in the persulfate activation system has not been systematically studied.

[0012] Based on this, the present invention creatively proposes to introduce sodium acetate into the persulfate reaction system and confirms that it can significantly enhance the degradation efficiency of persulfate on pollutants under various activation methods such as heterogeneous catalytic activation, homogeneous catalytic activation, thermal activation, and ultraviolet light activation. The present invention provides a new idea for the development of efficient and low-cost wastewater treatment technologies.

[0013] The present invention has the following advantages: 1. By adding sodium acetate, the present invention can significantly promote the activation effect of persulfate in various activation methods such as heterogeneous catalytic activation, homogeneous catalytic activation, thermal activation, and ultraviolet light activation. Compared with the case without adding sodium acetate, the activation efficiency of persulfate is significantly improved, greatly enhancing the degradation ability of pollutants in wastewater.

[0014] 2. This method is applicable to the degradation of various types of organic substances and has good degradation effects on organic pollutants in wastewater (such as antibiotics, phenols, personal care products, etc.), with a wide range of applications.

[0015] 3. The sodium acetate used in the present invention is inexpensive and widely sourced. While improving the treatment effect, it will not significantly increase the wastewater treatment cost, and has good economic and environmental benefits; moreover, sodium acetate can serve as a carbon source for microorganisms and will not introduce a large amount of secondary pollutants, meeting the requirements of green environmental protection.

[0016] 4. This method is simple to operate, does not require additional equipment, reduces energy consumption and treatment costs, is easy to realize industrial application, and has good economy and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 For Example 1, it is the effect diagram of bisphenol A degradation by activating persulfate with metal oxide (CoCuO x ); Figure 2 For Example 2, it is the effect diagram of tetracycline degradation by activating persulfate with metal oxide (MnO x ); Figure 3 For Example 3, it is the effect diagram of sulfamethoxine degradation by activating persulfate with metal oxide (CoCuO x ); Figure 4 For Example 4, it is the effect diagram of tetracycline degradation by thermally activating persulfate; Figure 5 For Example 5, it is the effect diagram of tetracycline degradation by ultraviolet-activated persulfate; Figure 6 For Example 6, it is the effect diagram of tetracycline degradation by activating persulfate with transition metal ions. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention will be further described below in conjunction with the drawings and examples, but it shall not be used as a basis for limiting the present invention. Examples

[0019] Prepare a 20 mg / L bisphenol A pollutant solution and prepare a CoCuO x metal oxide catalyst. Measure 50 mL of the bisphenol A pollutant solution into a beaker and add 5 mg of the CoCuO x catalyst. Prepare 6 identical CoCuO x / Bisphenol A mixed solution, different amounts of sodium acetate were added according to the settings, and one portion did not add sodium acetate. Six portions of the mixed solution were placed in a 25 °C water bath and stirred. After stirring until adsorption saturation, 5 mg of persulfate was added to each, and the degradation experiment was started. Samples were taken at intervals, and the concentration of bisphenol A was detected using a liquid chromatograph.

[0020] The results are as Figure 1 shown. In the system without adding sodium acetate, only 50% of bisphenol A could be removed within 15 minutes. When 5 mmol / L of sodium acetate was added to the reaction system, 100% of bisphenol A could be removed within 15 minutes. When the addition amount of sodium acetate was increased to 10 and 20 mmol / L, bisphenol A could be completely removed within 10 minutes. When the addition amount of sodium acetate was further increased to 30 and 40 mmol / L, the pollutant removal efficiency decreased, but was still much higher than the system without adding sodium acetate. And adding sodium acetate alone could hardly degrade the pollutant. This example shows that sodium acetate can promote the activation and degradation of pollutants by persulfate in the activation of functional materials with persulfate. Example

[0021] Prepare a 20 mg / L solution of tetracycline hydrochloride pollutant and prepare MnO x metal oxide catalyst. Respectively take 50 mL of the tetracycline hydrochloride pollutant solution and 5 mg of MnO x catalyst in two beakers. One portion was added with 0.5 mmol / L of sodium acetate, and one portion did not add sodium acetate. The two beakers were placed in a 25 °C water bath and stirred. After stirring until adsorption saturation, 10 mg of persulfate was added to each, and the degradation experiment was started. Samples were taken at intervals, and the concentration of tetracycline was detected using a liquid chromatograph. The results are as Figure 2 shown. In the system without adding sodium acetate, the removal rates of tetracycline hydrochloride were 10% and 30% at 1 minute and 3 minutes of degradation, respectively; while the removal rates of tetracycline in the system with added sodium acetate were 48% and 55%, respectively, and the removal effects on pollutants were increased by 4.8 and 1.8 times respectively. This example shows that sodium acetate can promote the activation and degradation of pollutants by persulfate in the activation of functional materials with persulfate. Example

[0022] Prepare a 20 mg / L solution of sulfadimethoxine pollutant, and prepare MOF-CoCuO x metal oxide catalyst. Respectively take 50 mL of the sulfadimethoxine pollutant solution and 10 mg of MOF-CoCuO xThe catalyst was placed in three beakers, and 0, 1, and 3 mmol / L of sodium acetate were added respectively. The three beakers were placed in a 25 °C water bath and stirred. After stirring until adsorption saturation, 10 mg of persulfate was added to each to initiate the degradation experiment. Samples were taken at intervals, and a liquid chromatograph was used to detect the sulfadimethoxine concentration. The results are as Figure 3 shown. In the system without added sodium acetate, 86% of the pollutants could be removed within 15 minutes; in the system with 1 mmol / L of sodium acetate added, 100% of the pollutants could be removed within 5 minutes. In the system with 3 mmol / L of sodium acetate added, the pollutants could be completely removed within 1 minute. This example shows that sodium acetate can effectively promote the activation of persulfate by functional materials to degrade pollutants. Example

[0023] A 20 mg / L tetracycline pollutant solution was prepared. 50 mL of the tetracycline pollutant solution was taken and placed in two beakers. 0.5 mmol / L of sodium acetate was added to one portion, and no sodium acetate was added to the other portion. 10 mg of persulfate was added under ultraviolet light to initiate the degradation experiment. Samples were taken at intervals, and a liquid chromatograph was used to detect the tetracycline concentration. The results are as Figure 4 shown. In the system without added sodium acetate, the degradation rate of tetracycline was 28%; in the system with 0.5 mmol / L of sodium acetate added, the degradation rate of tetracycline was 54%, which was 1.93 times that of the system without added sodium acetate. This example shows that sodium acetate can promote the activation of persulfate by ultraviolet light to degrade pollutants. Example

[0024] A 20 mg / L tetracycline pollutant solution was prepared. 50 mL of the tetracycline pollutant solution was taken and placed in two beakers. 0.5 mmol / L of sodium acetate was added to one portion, and no sodium acetate was added to the other portion. It was placed in a 50 °C water bath and stirred. After stabilization, 10 mg of persulfate was added to initiate the degradation experiment. Samples were taken at intervals, and a liquid chromatograph was used to detect the tetracycline concentration. The results are as Figure 5 shown. In the system without added sodium acetate, the degradation rate of tetracycline was 60%; in the system with 0.5 mmol / L of sodium acetate added, the degradation rate of tetracycline was 80%, which was 1.33 times that of the system without added sodium acetate. This example shows that sodium acetate can promote the activation of persulfate by heat to degrade pollutants. Example

[0025] Prepare a 20 mg / L tetracycline pollutant solution. Take 50 mL of the tetracycline pollutant solution and 1 mmol / L cobalt ions in two beakers respectively. Add 0.5 mmol / L sodium acetate to one portion and do not add sodium acetate to the other portion. Place them in a 25 °C water bath and stir. After stabilization, add 10 mg of persulfate to start the degradation experiment. Take samples at intervals and use a liquid chromatograph to detect the tetracycline concentration. The results are as Figure 6 shown. In the system without adding sodium acetate, it takes 3 minutes to completely degrade tetracycline; while in the system with 0.5 mmol / L sodium acetate added, tetracycline can be completely degraded within 1 minute. This example shows that sodium acetate can effectively promote the activation of persulfate to degrade pollutants in the activation of transition metal ions with persulfate.

[0026] The above provides a detailed introduction to a method for promoting the activation of persulfate to remove organic pollutants, but it is not used to limit the implementation mode of the present invention. For researchers in the field, other different forms of changes and variations can be made based on the above description, and all these changes and variations are included in the protection scope required by the present invention.

Claims

1. A method for promoting the activation of hydrogen persulfate to remove organic pollutants, characterized in that: Sodium acetate is used as an additive to enhance the effect of hydrogen persulfate in activating and degrading water pollutants, wherein the amount of sodium acetate added is ≤50 mmol / L.

2. A method for promoting the activation of hydrogen persulfate to remove organic pollutants according to claim 1, characterized in that: The method specifically includes adding hydrogen persulfate and sodium acetate to wastewater containing organic pollutants, and activating the hydrogen persulfate using different activation methods; wherein the activation method is one or more of heterogeneous catalytic activation, homogeneous catalytic activation, thermal activation and photoactivation.

3. The method for improving the activation efficiency of hydrogen persulfate by using an additive according to claim 2, characterized in that: When the activation method is heterogeneous catalyst activation, the catalyst used is a metal oxide or sulfide, and the metal ion is one or more transition metals of cobalt, iron, manganese, and copper, and the dosage is 50-200 mg / L.

4. The method of claim 2, wherein the additive improves the activation efficiency of hydrogen persulfate. When the activation method is homogeneous catalytic activation, the catalyst used is a soluble metal salt, and the metal ion is one or more transition metals of cobalt, iron, manganese, and copper, and the dosage is 0.5-5 mmol / L.

5. The method of claim 2, wherein the additive improves the activation efficiency of hydrogen persulfate, When the activation method is thermal activation, the reaction temperature is room temperature to 60°C.

6. The method of claim 2, wherein the additive improves the activation efficiency of hydrogen persulfate, When the activation method is photoactivation, the light is ultraviolet light.

7. The method for promoting the activation efficiency of hydrogen persulfate with an additive according to claim 2, characterized in that the organic pollutants include one or more of antibiotics, dyes, and pesticides that are difficult to degrade.

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