Composite type photo-fenton catalyst, preparation method thereof and application thereof in degrading rhodamine B in water

Abstract

The application relates to a composite type photo-Fenton catalyst, a preparation method thereof and application in degrading rhodamine B in water, and belongs to the field of pollutant degradation. The application adopts a one-step hydrothermal synthesis process to construct a heterojunction structure Fe 1.833 (OH) 0.5 O 2.5 / In(OH)3, so that the two functional components form an interface with close combination and high stability, and the synergistic effect of the catalytic system is effectively strengthened. Results show that the catalyst has extremely strong degradation capacity for rhodamine B under normal environmental conditions of normal temperature and normal pressure, and more than 90% removal rate can be achieved in a short reaction time, and the coupling degradation effect of photocatalysis and Fenton reaction is very prominent. The preparation method is simple, the reaction condition is mild, the cost of raw materials is low, no complex subsequent purification and modification treatment is needed, and the method has good industrialization amplification production potential. The method can efficiently treat various types of refractory organic pollutants in water, and has remarkable economic value and ecological environment benefits.

Description

Technical Field

[0001] This invention relates to the field of pollutant degradation, specifically to a composite photo-Fenton catalyst, its preparation method, and its application in the degradation of Rhodamine B in water. Background Technology

[0002] With the accelerating pace of industrialization and the continuous expansion of industries such as textile printing and dyeing, and daily chemical products, while enriching the supply of social materials, water pollution problems have become increasingly prominent. Organic dye wastewater, as a typical difficult-to-treat water pollutant, is characterized by its large discharge volume, deep color, complex composition, and significant biological toxicity, making it a key focus and challenge in water environment remediation both domestically and internationally. After dye pollutants flow into natural water bodies, they not only alter the appearance of the water body and block sunlight, disrupting normal aquatic ecological cycles, but some dye molecules and their intermediate degradation products can also harm human health through water circulation. Current mainstream water treatment technologies such as physical adsorption, coagulation sedimentation, and biodegradation generally suffer from insufficient adsorption capacity, large amounts of by-product sludge, long treatment cycles, and difficulty in efficiently degrading highly stable organic dyes. Therefore, developing novel catalytic materials and water treatment technologies with high degradation efficiency, fast reaction rates, low cost, simple operation, and environmental friendliness has become an urgent research direction in the field of environmental functional materials.

[0003] Addressing the existing challenges in the treatment of organic dye wastewater, this invention adheres to the design concept of green preparation and synergistic composite functions, and innovatively adopts a one-step hydrothermal synthesis process to prepare Fe with tight interfacial bonding. 1.833 (OH) 0.5 O 2.5 / In(OH)3 photo-Fenton catalyst. This synthesis process is simple and highly integrated. By precisely controlling the reaction temperature, duration, and precursor ratio of the hydrothermal system, nanocomposite materials of two phases are completed in a single reaction system, constructing a strongly interacting heterojunction interface. The unique heterojunction structure effectively accelerates the separation and transport of photogenerated carriers. Combined with the material's abundant surface active sites and large specific surface area, it simultaneously possesses excellent pollutant adsorption performance and superior photo-Fenton catalytic activity. Experiments have confirmed that under ambient temperature and pressure conditions, relying on the synergistic effect of photocatalysis and Fenton reaction, this catalyst can rapidly degrade typical organic pollutant RB in water, achieving a degradation rate of over 90% in a short time. The entire preparation process is mild, using cost-effective iron-based and indium-based raw materials. It eliminates the need for high-temperature calcination, the addition of complex additives, and complicated subsequent purification processes, effectively reducing production energy consumption and costs, creating favorable conditions for large-scale material production and practical wastewater treatment applications.

[0004] The Fe developed in this invention 1.833 (OH) 0.5 O 2.5The / In(OH)3 photo-Fenton catalyst provides a novel, efficient, economical, and green solution for treating recalcitrant organic dye wastewater. This material exhibits excellent catalytic degradation of RB (residue-containing dyes), and, thanks to its tunable heterojunction structure and universal synthetic route, also shows good potential for treating azo dyes, anthraquinones, and other common organic pollutants. This research not only expands the scope of iron-based composite catalytic materials and improves the preparation process of heterojunction photo-Fenton catalysts, but also further elucidates the synergistic catalytic mechanism at the two-phase interface, providing theoretical reference and technical support for the low-cost implementation and efficient operation of advanced oxidation technologies in practical wastewater treatment scenarios. This catalyst boasts excellent comprehensive performance and outstanding practical value, possessing considerable environmental, economic, and social benefits, and has a very broad prospect for industrial application. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention designs and synthesizes a composite photo-Fenton catalyst, its preparation method, and its application in the degradation of Rhodamine B in water.

[0006] The technical solution adopted in this invention is: a method for preparing a composite photo-Fenton catalyst, comprising the following steps:

[0007] 1) Fe was obtained by dissolving anhydrous ferric chloride, indium chloride tetrahydrate, and sodium hydroxide in water and then using a one-step hydrothermal synthesis method. 1.833 (OH) 0.5 O 2.5 / In(OH)3;

[0008] 2) The composite material obtained in step 1) is centrifuged and washed multiple times;

[0009] 3) The composite material obtained in step 2) is dried to obtain a composite photo-Fenton catalyst, namely Fe 1.833 (OH) 0.5 O 2.5 / In(OH)3 photo-Fenton catalyst.

[0010] In the preparation method of the above-mentioned composite photo-Fenton catalyst, in step 1), the solid-liquid ratio is 243 mg: 440 mg: 1200 mg: 50 mL for anhydrous ferric chloride: indium chloride tetrahydrate: sodium hydroxide: water.

[0011] In the preparation method of the above-mentioned composite photo-Fenton catalyst, in step 1), the hydrothermal synthesis method has a hydrothermal reaction temperature of 150-170℃ and a hydrothermal time of 16-18h.

[0012] In the preparation method of the above-mentioned composite photo-Fenton catalyst, in step 2), the centrifugal washing is performed at a speed of 6000 rpm and the washing is performed 4 times.

[0013] In the above-mentioned method for preparing a composite photo-Fenton catalyst, in step 3), the drying temperature is 50-70℃ and the drying time is 8-10h.

[0014] A composite photo-Fenton catalyst prepared according to the above preparation method.

[0015] Application of the above-mentioned composite photo-Fenton catalyst in the degradation of Rhodamine B in water.

[0016] The above-mentioned composite photo-Fenton catalyst is used in the degradation of Rhodamine B in water as follows: Under xenon lamp irradiation, the composite photo-Fenton catalyst is immersed in a Rhodamine B solution, and H2O2 is added to degrade Rhodamine B.

[0017] The above-mentioned composite photo-Fenton catalyst was used in the degradation of Rhodamine B in water. The solid-liquid ratio of the composite photo-Fenton catalyst to the Rhodamine B solution was 20 mg: 20 mL, the concentration of the Rhodamine B solution was 1 × 10⁻⁵ M, and the volume ratio of H₂O₂ to the Rhodamine B solution was 0.2-1 mL: 20 mg.

[0018] This invention utilizes a constructed Fe 1.833 (OH) 0.5 O 2.5 In(OH)3 photo-Fenton catalyst can achieve highly efficient photocatalytic degradation of RB. The beneficial effects of this method can be attributed to two aspects:

[0019] 1. Excellent catalytic performance and outstanding degradation efficiency. The two components form a tightly bound heterojunction interface, effectively promoting the separation of photogenerated electron-hole pairs and enhancing the synergistic effect of photocatalysis and Fenton reaction. Under normal temperature and pressure conditions, this catalyst can rapidly degrade RB in water, with a degradation rate exceeding 90% in a short time, demonstrating good treatment capabilities for high-color, recalcitrant organic dye wastewater.

[0020] 2. The preparation process is simple and the production cost is low. This study adopts a one-step hydrothermal synthesis method with mild reaction conditions, eliminating the need for high-temperature calcination, complex template agents, and cumbersome subsequent purification processes. The iron and indium sources used are readily available and inexpensive, significantly reducing the energy consumption and economic cost of material preparation, and enabling industrial-scale production.

[0021] The catalyst described in this invention has a wide range of applications and significant comprehensive benefits. This heterojunction composite material exhibits stable structure and good environmental compatibility, and besides RB, it also shows potential for treating other types of organic dyes and recalcitrant organic pollutants in water. It can provide a new technical approach for the treatment of water environments such as dyeing and printing wastewater, offering significant environmental, economic, and social benefits. Attached Figure Description

[0022] Figure 1 Fe in Example 1 1.833 (OH) 0.5 O 2.5 XRD pattern of / In(OH)3 photo-Fenton catalyst.

[0023] Figure 2 In Example 2, at 20 mL 1×10 -5 Add 20 mg Fe to M RB solution 1.833 (OH) 0.5 O 2.5 UV absorption spectra of / In(OH)3 photo-Fenton catalyst and 1 mL H2O2.

[0024] Figure 3 In Example 2, at 20 mL 1×10 -5 Add 20 mg Fe to M RB solution 1.833 (OH) 0.5 O 2.5 Degradation efficiency of / In(OH)3 photo-Fenton catalyst and 1 mL H2O2.

[0025] Figure 4 In Example 2, at 20 mL 1×10 -5 Add 20 mg Fe to M RB solution 1.833 (OH) 0.5 O 2.5 UV absorption spectra of In(OH)3 photo-Fenton catalyst and 200 μL H2O2.

[0026] Figure 5 In Example 2, at 20 mL 1×10 -5 Add 20 mg Fe to M RB solution 1.833 (OH) 0.5 O 2.5 Degradation efficiency of / In(OH)3 photo-Fenton catalyst and 200μL H2O2. Detailed Implementation

[0027] To better understand the technical solution of the present invention, specific embodiments are provided for further detailed description, but the solution is not limited thereto.

[0028] Example 1: Composite Photo-Fenton Catalyst Photo-Fenton Catalyst Fe 1.833 (OH) 0.5 O 2.5 / In(OH)3

[0029] The preparation method is as follows:

[0030] 1) Add 243 mg of anhydrous ferric chloride, 440 mg of indium chloride tetrahydrate and 1200 mg of sodium hydroxide to 50 mL of water, then transfer the mixed solution to a high-pressure reactor and keep it at 160 °C for 16 h.

[0031] 2) Centrifuge the obtained product at 4000 rpm. Repeat the washing process 4 times;

[0032] 3) Heating at 60℃ for 6 hours and drying yielded the composite photo-Fenton catalyst Fe. 1.833 (OH) 0.5 O 2.5 / In(OH)3.

[0033] For the Fe prepared in step 3), 1.833 (OH) 0.5 O 2.5 XRD analysis was performed on the / In(OH)3 photo-Fenton catalyst, and the results are as follows: Figure 1 As shown in the figure, Fe can be seen from the graph. 1.833 (OH) 0.5 O 2.5 The characteristic peaks of / In(OH)3 indicate the successful preparation of this photo-Fenton catalyst.

[0034] Example 2 Fe 1.833 (OH) 0.5 O 2.5 Application of In(OH)3 photo-Fenton catalyst in the degradation of RB in water

[0035] The Fe prepared in Example 1 1.833 (OH) 0.5 O 2.5 The degradation of RB using In(OH)3 photo-Fenton catalyst and UV absorption spectroscopy was investigated. The test procedure was as follows: RB was degraded using 20 mL of 1×10⁻⁶ In(OH)₃ photo-Fenton catalyst. -5 Add 20 mg Fe to M RB solution 1.833 (OH) 0.5 O 2.5 / In(OH)3 photo-Fenton catalyst, under xenon lamp irradiation, 1 mL H2O2 and 200 μL H2O2 were added respectively to achieve the degradation of RB, such as Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the Fe prepared in Example 1 1.833 (OH) 0.5 O 2.5The / In(OH)3 photo-Fenton catalyst can achieve highly efficient photo-Fenton degradation of RB with an efficiency of 90% after 30 minutes of light irradiation and the addition of 1 mL of H2O2; even with the addition of a trace amount of 200 μL of H2O2, highly efficient photo-Fenton degradation of RB can still be achieved with an efficiency of 40%.

Claims

1. A method for preparing a composite photo-Fenton catalyst, characterized in that, Includes the following steps: 1) Anhydrous ferric chloride, indium chloride tetrahydrate and sodium hydroxide were dissolved in water, and Fe 1.833 (OH) 0.5 O 2.5 / In(OH)3; 2) The composite material obtained in step 1) is centrifuged and washed multiple times; 3) drying the composite obtained in step 2) to obtain a composite type photo-Fenton catalyst, i.e. Fe 1.833 (OH) 0.5 O 2.5 / In(OH)3 photo-Fenton catalyst.

2. The method for preparing a composite photo-Fenton catalyst according to claim 1, characterized in that, In step 1), the solid-liquid ratio is 243 mg: 440 mg: 1200 mg: 50 mL for anhydrous ferric chloride: indium chloride tetrahydrate: sodium hydroxide: water.

3. The method for preparing a composite photo-Fenton catalyst according to claim 1, characterized in that, In step 1), the hydrothermal synthesis method involves a hydrothermal reaction at a temperature of 150-170℃ and a hydrothermal time of 16-18h.

4. The method for preparing a composite photo-Fenton catalyst according to claim 1, characterized in that, In step 2), the centrifugal washing is performed at a speed of 6000 rpm and the washing is repeated 4 times.

5. The method for preparing a composite photo-Fenton catalyst according to claim 1, characterized in that, In step 3), the drying temperature is 50-70℃ and the drying time is 8-10h.

6. A composite photo-Fenton catalyst prepared according to any one of claims 1-5.

7. The application of the composite photo-Fenton catalyst according to claim 6 in the degradation of Rhodamine B in water.

8. The application of the composite photo-Fenton catalyst according to claim 7 in the degradation of Rhodamine B in water, characterized in that, The method is as follows: Under xenon lamp irradiation, the composite photo-Fenton catalyst is immersed in a Rhodamine B solution, and H2O2 is added to degrade Rhodamine B.

9. The application of the composite photo-Fenton catalyst according to claim 8 in the degradation of Rhodamine B in water, characterized in that, The solid-liquid ratio of the composite Fenton-like catalyst and rhodamine B solution was 20 mg:20 mL, and the concentration of the rhodamine B solution was 1*10 -5 The volume ratio of M, H2O2 and rhodamine B solution was 0.2-1 mL:20 mg.

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