Tetracycline degradation method based on cu-cnv heterogeneous fenton-like catalyst

Abstract

This invention relates to a method for tetracycline degradation based on a Cu-CNv heterogeneous Fenton-like catalyst. Using Cu-CNv as the catalyst, this invention utilizes heterogeneous Fenton-like advanced oxidation technology to mineralize and decompose antibiotics adsorbed in the aquatic environment. It exhibits high catalytic efficiency; the Cu-CNv heterojunction achieves a 93.98% degradation rate of 50 mg / L tetracycline-like Fenton within 40 minutes. The method is simple to operate, has good catalyst stability, and does not produce copper sludge. It solves the problems of traditional homogeneous Fenton technology, such as narrow pH range, inability to recover the catalyst, high H2O2 consumption, low catalytic efficiency, and low active sites.

Description

Technical Field

[0001] This invention relates to the field of Fenton-like catalysts, and more specifically to a method for tetracycline degradation based on a Cu-CNv heterogeneous Fenton-like catalyst. Background Technology

[0002] Antibiotic-induced water pollution has caused serious harm to humans and ecosystems, and is a key challenge in my country's wastewater treatment. Traditional homogeneous Fenton technology can effectively remove recalcitrant pollutants, but Cu... 2+ The concentration of H2O2, the ratio of H2O2 to the concentration, pH value, and temperature will all affect the reaction rate, and sludge is easily generated, making it difficult to recover the catalyst after the reaction. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a tetracycline degradation method based on Cu-CNv heterogeneous Fenton catalyst, which addresses the above-mentioned shortcomings.

[0004] To solve the above technical problems, the present invention adopts the following technical solution:

[0005] The tetracycline degradation method based on Cu-CNv heterogeneous Fenton-like catalyst includes the following steps:

[0006] Step 1: Preparation of Cu-CNv heterogeneous Fenton-like catalyst, specifically including the following steps:

[0007] Step 1.1: After calcining urea at high temperature in a crucible, a g-C3N4 sample (named CN) is obtained;

[0008] Step 1.2: Add the calcined CN to deionized water containing NaBH4, and after ultrasonic dispersion and stirring, obtain CNv suspension;

[0009] Step 1.3: After adding Cu(NO3)2·3H2O solution to CNv suspension, ultrasonically disperse for more than 5 minutes, and then stir on a magnetic stirrer for 3 hours;

[0010] Step 1.4: After the reaction in the previous step is completed, the obtained product is washed multiple times by centrifugation with deionized water and ethanol, and then dried to obtain the Cu-CNv heterogeneous Fenton catalyst;

[0011] Step 2: Add the Cu-CNv heterogeneous Fenton catalyst from the previous step to the tetracycline solution to degrade the tetracycline.

[0012] Furthermore, the magnetic stirrer is a multi-station magnetic stirrer.

[0013] Furthermore, in step 1.2, the volume of deionized water containing NaBH4 is 40 mL, and the concentration of NaBH4 is 1 mol / L.

[0014] Furthermore, the CN mass fraction in the CNv suspension is 0.8%.

[0015] Furthermore, in step 1.3, the concentration of the Cu(NO3)2·3H2O solution is 0.05 mol / L, and the volume is 800 μL.

[0016] The beneficial effects of this invention are as follows:

[0017] The Cu-CNv heterogeneous Fenton-like catalyst obtained in this invention can mineralize and decompose antibiotics adsorbed in the aquatic environment. It exhibits high catalytic efficiency; the Cu-CNv heterojunction achieves a 93.98% degradation rate of 50 mg / L tetracycline Fenton within 40 minutes. The process is simple, the catalyst has good stability, and it does not produce copper sludge. It solves the problems of traditional homogeneous Fenton technology, such as narrow pH range, inability to recover the catalyst, high H2O2 consumption, low catalytic efficiency, and low active sites. Furthermore, experiments demonstrate that compared to the monomeric CN, the Cu-CNv composite material has stronger adsorption performance and a significantly improved degradation rate, achieving a maximum Fenton-like degradation rate of 93.98% after 40 minutes of reaction.

[0018] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] Figure 1 Figure (A) shows the adsorption-degradation performance test of tetracycline by Cu-CNv, Cu-CNv / H2O2, CN and CN / H2O2 heterojunctions, and Figure (B) shows the columnar degradation diagram of Cu-CNv, Cu-CNv / H2O2, CN and CN / H2O2 heterojunctions at 40 min.

[0020] Figure 2 Figure (A) shows the universality of the Cu-CNv / H2O2 system (target pollutant concentration is 20 mg / L), and Figure (B) shows the XRD pattern of the CN and Cu-CNv heterojunction. Detailed Implementation

[0021] The following embodiments are provided to better understand the present invention, but are not intended to limit the invention. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods. Unless otherwise specified, the experimental materials used in the following embodiments were purchased from conventional biochemical reagent stores.

[0022] Step 1: Preparation of Cu-CNv heterogeneous Fenton-like catalyst, specifically including the following steps:

[0023] Step 1.1: Place 10g of urea in a crucible, initial temperature 20℃, heating time 106min, heating temperature 550℃, holding time 2h, holding temperature 550℃, heating rate 5℃ / min. Collect g-C3N4 sample (named CN);

[0024] Step 1.2: Take 0.4g CN and 1M NaBH4 and add them to 40ml of deionized water. After ultrasonic dispersion for 5min, a CNv suspension is obtained.

[0025] Step 1.3: Add 800 μL of 0.05 M Cu(NO3)2·3H2O to the CNv suspension obtained in Step 2, and then stir on a magnetic stirrer for 3 hours. After the reaction is complete, wash the product three times with deionized water and ethanol by centrifugation. Finally, dry under vacuum at 60 °C overnight (named Cu-CNv).

[0026] Heterogeneous Fenton-like method for tetracycline degradation: 40 mg of Cu-CNv catalyst was weighed and dispersed in a reactor containing 50 mL of tetracycline solution (50 mg / L TCH). Before the degradation experiment, the mixture was stirred in the dark for 30 min to allow the catalyst to reach TCH adsorption saturation. Then, 100 μL of H₂O₂ solution was added to the solution, and the reaction temperature was controlled at 25 °C using a low-temperature isothermal circulation system. At regular intervals, the reaction solution was removed, centrifuged, and filtered through a 0.22 μm filter membrane. Finally, the absorbance was measured using a spectrophotometer.

[0027] We tested the adsorption-degradation performance of Cu-CNv and CN materials for tetracycline, using 50 mg / L TCH as the target pollutant and 100 μL of H2O2 added. Figure 1 Figures (A) and (B) are the degradation performance graph and bar chart of the sample after 30 min of adsorption and 40 min of reaction, respectively. Compared with the monomeric CN material, the degradation rate of the Cu-CNv composite material is significantly improved, with the strongest Fenton-like degradation rate of 93.98% after 40 min of reaction. Figure 1 As shown in Figure (B), Cu-CNv / H2O2, Cu-CNv, CN / H2O2 and CN The degradation efficiencies of tetracycline at 40 minutes were 93.98%, 10.95%, 2.22%, and 0.06%, respectively.

[0028] Figure 2 Figure (A) shows the universality of the Cu-CNv / H2O2 system (target pollutant concentration is 20 mg / L), and Figure (B) shows the XRD pattern of the CN and Cu-CNv heterojunction.

[0029] The above description provides examples of the preferred embodiments of the present invention. Parts not detailed herein are common knowledge to those skilled in the art. The scope of protection of the present invention is determined by the claims. Any equivalent modifications based on the technical teachings of the present invention are also within the scope of protection of the present invention.

Claims

1. A method for tetracycline degradation based on Cu-CNv heterogeneous Fenton-like catalysts, characterized in that, Includes the following steps: Step 1: Preparation of Cu-CNv heterogeneous Fenton-like catalyst, specifically including the following steps: Step 1.1: After calcining urea at high temperature in a crucible, a g-C3N4 sample was obtained and named CN; Step 1.2: Add the calcined CN to deionized water containing NaBH4, and after ultrasonic dispersion and stirring, obtain a CNv suspension; the volume of deionized water containing NaBH4 is 40 mL, and the concentration of NaBH4 is 1 mol / L; Step 1.3: After adding Cu(NO3)2·3H2O solution to CNv suspension, ultrasonically disperse for more than 5 minutes, and then stir on a magnetic stirrer for 3 hours; In step 1.3, the concentration of the Cu(NO3)2·3H2O solution is 0.05 mol / L, and the volume is 800 μL; Step 1.4: After the reaction in the previous step is completed, the obtained product is washed multiple times by centrifugation with deionized water and ethanol, and then dried to obtain the Cu-CNv heterogeneous Fenton catalyst; Step 2: Add the Cu-CNv heterogeneous Fenton catalyst from the previous step to the tetracycline solution to degrade the tetracycline.

2. The tetracycline degradation method based on Cu-CNv heterogeneous Fenton catalyst according to claim 1, characterized in that, The magnetic stirrer is a multi-station magnetic stirrer.

3. The tetracycline degradation method based on Cu-CNv heterogeneous Fenton-like catalyst according to claim 1, characterized in that, The CN mass fraction in the CNv suspension is 0.8%.

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