Application of fe-ni2s4 spinel in heterogeneous catalytic hydrogen peroxide removal of tetracycline antibiotic organic pollutants

Abstract

This invention discloses the application of FeNi2S4 spinel in heterogeneous catalytic hydrogen peroxide removal of tetracycline antibiotic organic pollutants. For the first time, FeNi2S4 spinel catalyst is applied to the H2O2 system to remove tetracycline antibiotic organic pollutants. The degradation rate of tetracycline reaches more than 90% within 120 min over a wide pH range (pH 3-9), which is nearly 40% higher than the efficiency of undoped Sulfur FeNi2O4. This invention solves the bottlenecks of traditional H2O2 activated catalysts, such as poor stability, narrow pH range, and high risk of metal leaching.

Description

Technical Field

[0001] This invention relates to the field of environmental pollution control technology, specifically to the application of FeNi2S4 spinel in heterogeneous catalytic hydrogen peroxide removal of tetracycline antibiotic organic pollutants. Background Technology

[0002] Tetracycline antibiotics, as broad-spectrum antibacterial drugs, are widely used in livestock and poultry farming, aquaculture, and clinical medicine. Due to their stable chemical structure, poor biodegradability, and high water solubility, they continuously enter the aquatic environment through wastewater discharge and soil infiltration, forming persistent residues. Long-term low-concentration tetracycline residues not only disrupt the balance of aquatic ecosystems and induce drug-resistant genes in microorganisms, but also accumulate in the human body through the food chain, threatening human health. Traditional wastewater treatment processes such as biological treatment and coagulation sedimentation have limited effectiveness in removing tetracycline and struggle to achieve efficient degradation. Therefore, developing efficient and environmentally friendly tetracycline wastewater treatment technologies has become a research hotspot in the environmental field.

[0003] Advanced oxidation-activated hydrogen peroxide (H2O2) systems can efficiently mineralize recalcitrant organic pollutants by initiating the generation of strong oxidizing species such as hydroxyl radicals (·OH). They offer advantages such as rapid reaction rates, wide applicability, and no secondary biotoxic residues, making them particularly suitable for scenarios where conventional biochemical processes struggle to treat pharmaceutical wastewater and industrial effluent. However, hydrogen peroxide utilization is relatively low, and some processes require the addition of iron-based or cobalt-based catalysts, posing environmental risks from metal ion leaching. Assisted methods such as ultraviolet and ultrasonic treatments are energy-intensive, resulting in high operating costs. Current technological bottlenecks mainly focus on three aspects: first, insufficient catalyst stability, leading to easy deactivation or difficulty in recovery; second, a narrow applicable solution pH range; and third, significant issues such as uneven mass transfer and competing side reactions, resulting in decreased treatment efficiency. Developing green and recyclable catalytic materials while reducing reagent and energy costs remains a key challenge for the engineering and widespread application of this technology. Summary of the Invention

[0004] The purpose of this invention is to provide the application of FeNi2S4 spinel in the heterogeneous catalytic removal of tetracycline antibiotic organic pollutants by hydrogen peroxide, which solves the problems of low H2O2 utilization, easy dissolution of metal catalysts, narrow pH range, poor stability and high operating costs in the existing advanced oxidation-activated H2O2 system.

[0005] This invention is achieved through the following technical solutions:

[0006] The application of FeNi2S4 spinel in heterogeneous catalytic hydrogen peroxide removal of tetracycline antibiotic organic pollutants includes the following steps: adding H2O2 and FeNi2S4 spinel catalyst to wastewater containing tetracycline pollutants.

[0007] Preferably, the concentration of tetracycline pollutant in the wastewater is 5-50 mg / L, the concentration of FeNi2S4 catalyst is 50-150 mg / L, the concentration of H2O2 is 3-4 g / L, and the pH is 3-9.

[0008] The FeNi2S4 spinel catalyst is prepared as follows: ferrous sulfate heptahydrate, nickel acetate tetrahydrate, and L-cysteine ​​are added to an ethylene glycol aqueous solution and stirred to dissolve. The solution is then transferred to a high-pressure reactor lined with polytetrafluoroethylene and kept at a constant temperature of 160°C for 12 hours. After cooling to room temperature, the resulting black product is collected by centrifugation and washed thoroughly three times with water and ethanol. Finally, it is dried in a vacuum drying oven at 60°C.

[0009] The beneficial effects of this invention are as follows: This invention is the first to apply FeNi2S4 spinel catalyst to the H2O2 system for the removal of tetracycline antibiotic organic pollutants. The degradation rate of tetracycline reaches more than 90% within 120 min in a wide pH range (pH 3-9), which is nearly 40% higher than the efficiency of FeNi2O4 without sulfur doping. By controlling the spinel crystal phase structure and electronic properties through sulfur doping, more active sites are exposed in the H2O2 system, which solves the bottlenecks of poor stability, narrow pH range and high risk of metal leaching of traditional H2O2 activation catalysts. Attached Figure Description

[0010] Figure 1 This is a SEM image of the sulfur-doped iron-nickel-based bimetallic spinel catalyst prepared in Example 1;

[0011] Figure 2 This is a SEM image of the NiFe2O4 catalyst;

[0012] Figure 3 This is a graph showing the effect of using the sulfur-doped iron-nickel-based bimetallic spinel catalyst FeNi2S4 in Example 1 to remove tetracycline antibiotic organic pollutants by hydrogen peroxide under different pH conditions in heterogeneous catalysis.

[0013] Figure 4 The graph shows the effect of using the undoped sulfur FeNi2O4 catalyst from Comparative Example 1 to remove tetracycline antibiotic organic pollutants by heterogeneous catalytic hydrogen peroxide under different pH conditions. Detailed Implementation

[0014] The following is a further description of the invention, but not a limitation thereof.

[0015] Preparation Example 1: Preparation of sulfur-doped iron-nickel-based bimetallic spinel:

[0016] 0.139 g of ferrous sulfate heptahydrate, 0.218 g of nickel acetate tetrahydrate, and 0.303 g of L-cysteine ​​were added to 25 mL of ethylene glycol aqueous solution (ethylene glycol to ultrapure water volume ratio 1:1). The solution was magnetically stirred for 30 min to dissolve the solution. The mixture was transferred to a 50 mL high-pressure reactor lined with polytetrafluoroethylene (PTFE), and then kept at 160 ℃ for 12 h. After cooling to room temperature, the resulting black product was collected by centrifugation and washed thoroughly three times with water and ethanol. It was then dried in a vacuum drying oven at 60 ℃ for 12 h to obtain sulfur-doped iron-nickel-based bimetallic spinel FeNi2S4. Its SEM image is shown below. Figure 1 .

[0017] Preparation of Comparative Example 1:

[0018] Referring to Preparation Example 1, the difference is that L-cysteine ​​was not added, resulting in undoped sulfur FeNi2O4, the SEM image of which can be found in [reference needed]. Figure 2 .

[0019] Application Example 1: Application of sulfur-doped iron-nickel-based bimetallic spinel catalyst FeNi2S4 in heterogeneous catalytic hydrogen peroxide removal of tetracycline antibiotic organic pollutants under different pH conditions

[0020] At room temperature, H2O2 and the sulfur-doped iron-nickel-based bimetallic spinel catalyst FeNi2S4 obtained in Example 1 were added to wastewater containing 15 mg / L tetracycline pollutant. The catalyst concentration was 100 mg / L, the H2O2 concentration was 3.3 g / L, and the pH was 3, 5, 7, and 9, respectively. The results are as follows. Figure 3 The results show that the sulfur-doped iron-nickel-based bimetallic spinel catalyst FeNi2S4 achieved a degradation efficiency of over 90% for 15 mg / L tetracycline within 120 min, indicating that the catalyst has excellent degradation effect on tetracycline.

[0021] Application Comparative Example 1:

[0022] Referring to Application Example 1, the difference is that the catalyst was the undoped sulfur FeNi2O4 obtained in Comparative Example 1. The results are as follows... Figure 4 The NiFe2O4 catalyst achieved a degradation efficiency of only about 50% for 15 mg / L tetracycline within 120 min.

[0023] A comparison of Application Example 1 and Application Comparative Example 1 shows that the sulfur-doped iron-nickel-based bimetallic spinel FeNi2S4 of the present invention helps to improve catalytic activity.

Claims

1. Use of FeNi2S4 spinel for the removal of tetracycline antibiotic organic pollutants by heterogeneous catalysis of hydrogen peroxide, characterized in that, Includes the following steps: H2O2 and FeNi2S4 spinel catalyst were added to wastewater containing tetracycline pollutants.

2. The application according to claim 1, characterized in that, The concentration of tetracycline pollutant in the wastewater is 5-50 mg / L, the concentration of FeNi2S4 catalyst is 50-150 mg / L, the concentration of H2O2 is 3-4 g / L, and the pH is 3-9.

3. The application according to claim 1, characterized in that, The FeNi2S4 spinel catalyst is prepared as follows: ferrous sulfate heptahydrate, nickel acetate tetrahydrate, and L-cysteine ​​are added to an ethylene glycol aqueous solution and stirred to dissolve. The solution is then transferred to a high-pressure reactor lined with polytetrafluoroethylene and kept at a constant temperature of 160℃ for 12 h. After cooling to room temperature, the resulting black product is collected by centrifugation and washed thoroughly three times with water and ethanol. Finally, it is dried in a vacuum drying oven at 60℃.

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