Method for atrazine degradation with solid-liquid separation

Abstract

This invention relates to a method for atrazine degradation that enables solid-liquid separation. The invention aims to address the technical problem of secondary pollution caused by the easy discharge of persulfate activation materials with the water body in existing advanced persulfate oxidation methods. The method involves weighing magnesium-iron layered hydroxide composite magnetic hydrothermal carbon and NaCl into the atrazine-contaminated liquid, placing it in a rotor, and stirring with a magnetic stirrer for 10 minutes. The mixture is then filtered using a vacuum filtration flask to separate the solid and liquid phases. The filtrate is retained, and potassium persulfate (PMS) is added to the filtrate. Stirring continues with a magnetic stirrer for another 30 minutes. This completes the process. This invention utilizes magnesium-iron layered hydroxide composite magnetic hydrothermal carbon to activate NaCl. ‑ The mechanism activates persulfate, enabling solid-liquid separation after activation. This improves the degradation performance of atrazine by persulfate while effectively achieving solid-liquid separation, avoiding secondary pollution to the environment. This invention belongs to the technical field of pollutant degradation.

Description

Technical Field

[0001] This invention relates to a method for atrazine degradation. Background Technology

[0002] Atrazine is a chemically stable triazine herbicide with long-term persistence, classifying it as a persistent pollutant. Atrazine residues in soil can migrate into groundwater and surface water, posing a threat to aquatic safety. Persulfate advanced oxidation technologies (PS-AOPs) utilize environmentally friendly persulfates as strong oxidants, directly added to the environment, achieving efficient degradation of organic pollutants while maintaining environmental friendliness. Therefore, PS-AOPs have broad application prospects in treating organic pollutants; however, the activating materials from persulfates are easily discharged into water bodies, posing a risk of secondary pollution.

[0003] Cl - Chlorine radicals are commonly found in surface water and, under certain conditions, can be excited to generate chlorine free radicals that catalyze persulfate formation. · Cl2 ·- ,OCl · Chlorine free radicals themselves exhibit high activity among organic micropollutants. Furthermore, chlorine free radicals can activate persulfate to generate highly oxidizing free radicals (SO4). ·- and OH·) and non-free radicals (HClO and 1 O2-type active substances can effectively improve the degradation effect of atrazine. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problem that the activation material of persulfate is easily discharged with water bodies and causes secondary pollution in the existing advanced persulfate oxidation technology, and to provide an atrazine degradation method that can achieve solid-liquid separation.

[0005] The following are methods for atrazine degradation that can achieve solid-liquid separation:

[0006] Weigh 0.01g of magnesium-iron layered hydroxide composite magnetic hydrothermal carbon and 0.05g of NaCl and add them to 100mL of atrazine-contaminated liquid with a concentration of 10mg / L. Place the mixture in a rotor and stir with a magnetic stirrer for 10 minutes. Then, filter the mixture using a vacuum filtration flask to separate the solid and liquid components. Retain the filtrate and add 0.25g of potassium persulfate (PMS) to the filtrate. Continue stirring with a magnetic stirrer for 30 minutes to complete the solid-liquid separation and degradation of atrazine.

[0007] This invention utilizes magnesium-iron layered hydroxide composite magnetic hydrothermal carbon to activate Cl -The mechanism activates persulfate, enabling solid-liquid separation after activation. This improves the performance of persulfate in degrading atrazine while effectively achieving solid-liquid separation, avoiding secondary pollution and demonstrating promising application prospects.

[0008] The present invention has the following advantages:

[0009] (1) Utilizing Cl, which is harmless to water bodies - As an intermediate medium for activating persulfate, it enables the catalyst to activate persulfate and efficiently degrade atrazine without entering the environmental water body.

[0010] (2) Magnesium-iron layered hydroxide composite magnetic hydrothermal carbon acts as the energy exciter in the system, activating Cl... - As an intermediate medium, it enables the catalyst to efficiently activate persulfate to degrade atrazine without entering the reaction water.

[0011] (3) This invention can effectively activate Cl - Activation of PMS and generation of various active substances ( 1 O2, HClO, Cl · Cl2 ·- 、OCl·), which synergistically and efficiently degrade atrazine in water. Attached Figure Description

[0012] Figure 1 This is a performance comparison chart of the atrazine degradation method without NaCl filtration and the atrazine degradation method without NaCl filtration.

[0013] Figure 2 This is a performance comparison chart of the atrazine degradation method that can achieve solid-liquid separation and the unfiltered atrazine degradation method;

[0014] Figure 3 This is an EPR spectrum of chlorine radicals from an atrazine degradation method that enables solid-liquid separation;

[0015] Figure 4 This is a comparison chart of hypochlorous acid production in atrazine degradation methods that can achieve solid-liquid separation, atrazine degradation methods in unfiltered systems, and solid-liquid separation systems without pollutants. Detailed Implementation

[0016] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.

[0017] Detailed implementation method: The atrazine degradation method that can achieve solid-liquid separation in this implementation method is as follows:

[0018] Weigh 0.01g of magnesium-iron layered hydroxide composite magnetic hydrothermal carbon and 0.05g of NaCl into 100mL of atrazine-contaminated liquid with a concentration of 10mg / L. Place the mixture in a rotor and stir with a magnetic stirrer for 10 minutes. Then, filter the mixture using a vacuum filtration flask to separate the solid and liquid components. Retain the filtrate and add 0.25g of potassium persulfate (PMS) to it. Continue stirring with a magnetic stirrer for 30 minutes to completely degrade 100mL of atrazine with a concentration of 10mg / L. This completes the solid-liquid separation and degradation of atrazine.

[0019] In this embodiment, the magnesium-iron layered hydroxide composite magnetic hydrothermal carbon was prepared in the laboratory.

[0020] The following experiments were used to verify the effectiveness of the invention:

[0021] Experiment 1:

[0022] The following are methods for atrazine degradation that can achieve solid-liquid separation:

[0023] Weigh 0.01g of magnesium-iron layered hydroxide composite magnetic hydrothermal carbon and 0.05g of NaCl into 100mL of atrazine-contaminated liquid with a concentration of 10mg / L. Place the mixture in a rotor and stir with a magnetic stirrer for 10 minutes. Then, filter the mixture using a vacuum filtration flask to separate the solid and liquid components. Retain the filtrate and add 0.25g of potassium persulfate (PMS) to it. Continue stirring with a magnetic stirrer for 30 minutes to completely degrade 100mL of atrazine with a concentration of 10mg / L. This completes the solid-liquid separation and degradation of atrazine.

[0024] Comparative experiment:

[0025] The atrazine degradation method for the filtration system without NaCl is as follows:

[0026] Weigh 0.01g of magnesium-iron layered hydroxide composite magnetic hydrothermal carbon and add it to 100mL of atrazine-contaminated liquid with a concentration of 10mg / L. Place the mixture in a rotor and stir with a magnetic stirrer for 10 minutes. Then, filter the mixture using a vacuum filtration flask to separate the solid and liquid components. Retain the filtrate and add 0.25g of potassium persulfate (PMS) to the filtrate. Continue stirring with a magnetic stirrer for 30 minutes to complete the solid-liquid separation and degradation of atrazine.

[0027] Operating method for hypochlorous acid production in a contaminant-free solid-liquid separation system:

[0028] Add 0.0 mL, 0.50 mL, 1.00 mL, 1.50 mL, 2.50 mL, 5.00 mL, and 7.50 mL of potassium iodate standard working solution to 50 mL colorimetric tubes, respectively. Add approximately 1 g of potassium iodide and 0.5 mL of sulfuric acid solution to each tube, mix well, and let stand for 2 minutes. Then add 0.5 mL of sodium hydroxide solution and dilute to the mark. Add 2.5 mL of phosphate buffer and 2.5 mL of LPD indicator, mix well, and immediately measure the absorbance at 515 nm using a UV spectrophotometer. Plot a standard curve of mass concentration versus absorbance values ​​using the obtained data, and derive the regression equation.

[0029] The method for determining the hypochlorous acid yield in the solid-liquid separation system is the same as above. Add 0.0 mL, 0.50 mL, 1.00 mL, 1.50 mL, 2.50 mL, 5.00 mL, and 7.50 mL of the test solution to 50 mL colorimetric tubes. Add 1 g of potassium iodide and 0.5 mL of sulfuric acid solution to each tube, mix well, and let stand for 2 minutes. Then add 0.5 mL of sodium hydroxide solution and dilute to the mark. Add 2.5 mL of phosphate buffer and 2.5 mL of LPD indicator, mix well, and immediately measure the absorbance at 515 nm using a UV spectrophotometer. Substitute the measured absorbance into the standard curve to calculate the hypochlorous acid concentration.

[0030] Magnesium-iron layered hydroxide composite magnetic hydrothermal carbon effectively activates NaCl within 10 minutes, enabling solid-liquid separation. The filtrate can effectively activate PMS and degrade 100 mL of 10 mg / L atrazine. Figure 1 , Figure 2 As shown.

[0031] The atrazine degradation method, which enables solid-liquid separation, generates free radical and non-free radical reactive substances that can be used to degrade atrazine, such as... Figure 2 As shown in the figure, the magnesium-iron layered hydroxide composite magnetic hydrothermal carbon can effectively activate Cl. - The generation of free radicals can better activate PMS in subsequent processes.

Claims

1. A method for atrazine degradation that enables solid-liquid separation, characterized in that... The atrazine degradation method that enables solid-liquid separation is as follows: Weigh 0.01g of magnesium-iron layered hydroxide composite magnetic hydrothermal carbon and 0.05g of NaCl and add them to 100mL of atrazine-contaminated liquid with a concentration of 10mg / L. Place the mixture in a rotor and stir with a magnetic stirrer for 10 minutes. Then, filter the mixture using a vacuum filtration flask to separate the solid and liquid components. Retain the filtrate and add 0.25g of potassium persulfate to the filtrate. Continue stirring with a magnetic stirrer for 30 minutes to complete the solid-liquid separation and atrazine degradation.

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