BiOCl / CuBi2O4 composite material, preparation method thereof and application of BiOCl / CuBi2O4 composite material in ultrasonic catalytic degradation of organic pollutants in wastewater
By using BiOCl/CuBi2O4 composite material as an acoustic catalyst to activate persulfate, the problem of high cost in the treatment of tetracycline-polluted water in existing technologies has been solved, and efficient and low-cost degradation of organic pollutants has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-04-14
AI Technical Summary
Existing technologies for treating tetracycline-contaminated water rely on mild persulfate oxidation processes, resulting in high treatment costs and large amounts of chemical reagents, making it difficult to efficiently degrade organic pollutants.
BiOCl/CuBi2O4 composite material was used as an acoustic catalyst. Persulfate was activated by ultrasonic treatment to improve the activity and stability of the catalyst, enhance the interfacial charge separation efficiency, and improve the catalytic degradation efficiency.
It significantly improves the activity of the catalyst in activating persulfate, greatly enhances the degradation efficiency, has strong anti-interference ability, is suitable for the efficient degradation of a variety of pollutants, and has abundant and inexpensive raw materials and a simple synthesis method.
Smart Images
Figure CN121847174A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of water treatment technology, specifically relating to a BiOCl / CuBi2O4 composite material, its preparation method, and its application in the ultrasonic catalytic degradation of organic pollutants in wastewater. Background Technology
[0002] Tetracycline antibiotics (TC) are among the most widely used antibiotics globally, especially in livestock farming where they are extensively used as growth promoters and therapeutic agents. This large-scale use results in significant amounts of unabsorbed tetracycline entering soil and water bodies through animal feces. In major livestock-producing countries like China, the detected concentration of tetracycline in the environment has reached thousands of nanograms per liter. Due to its stable chemical properties, tetracycline persists in the environment, accumulating and spreading, posing a global ecological and health hazard and a serious threat to ecosystem security and human health. Therefore, developing green, cost-effective, and efficient tetracycline degradation technologies has become a critical issue and research hotspot in the field of environmental science. Advanced oxidation technologies based on persulfate (PMS) have attracted considerable attention due to their strong oxidizing power, wide applicability, good stability, and lack of secondary pollution. However, the reaction conditions for persulfate oxidation are relatively mild, leading to high treatment costs and large amounts of chemical reagents required. Therefore, developing catalysts that can efficiently activate persulfate is crucial for research. Summary of the Invention
[0003] This invention provides a BiOCl / CuBi2O4 composite material, its preparation method, and its applications. When the BiOCl / CuBi2O4 composite material of this invention is used as an acoustic catalyst for the oxidation and degradation of recalcitrant organic pollutants in wastewater by persulfate, it can significantly improve the catalyst's activity in activating persulfate, greatly enhancing the degradation efficiency. Furthermore, this catalyst exhibits strong anti-interference ability, high stability, and is less affected by background ion interference in the water body, demonstrating considerable potential in the field of water pollution control.
[0004] The technical solution adopted in this invention is:
[0005] A BiOCl / CuBi2O4 composite material is made by combining BiOCl with a CuBi2O4 support, wherein the molar amount of BiOCl is 10%-30% of the molar amount of CuBi2O4.
[0006] The preparation method of the above-mentioned BiOCl / CuBi2O4 composite material is as follows: Bi(NO3)3·5H2O is added to CuBi2O4 suspension and stirred. Then KCl is added and stirred vigorously. The mixed solution is transferred to a high-pressure reactor for hydrothermal reaction. After the reaction is completed, the mixture is filtered, washed, and dried to obtain the BiOCl / CuBi2O4 composite material.
[0007] Furthermore, in the preparation method of the above-mentioned BiOCl / CuBi2O4 composite material, the hydrothermal reaction conditions are: reaction at 180℃ for 9 h.
[0008] Furthermore, in the preparation method of the above-mentioned BiOCl / CuBi2O4 composite material, the drying is carried out at 60 °C for 12 h.
[0009] Furthermore, the preparation method of the above-mentioned BiOCl / CuBi2O4 composite material, wherein the preparation method of CuBi2O4 is as follows: Cu(NO3)2·3H2O is dissolved in deionized water and stirred, while Bi(NO3)3·5H2O is added to it while stirring, and ultrasonically mixed. Then, NaOH solution is slowly added under vigorous stirring to obtain a blue-green suspension and continue stirring. After stirring is completed, a hydrothermal reaction is carried out. After the reaction is completed, the mixture is filtered, washed, dried, and ground to obtain CuBi2O4 powder.
[0010] Furthermore, in the above-mentioned method for preparing CuBi2O4, the hydrothermal reaction conditions are: reaction at 180 °C for 5 h.
[0011] Furthermore, in the above-mentioned method for preparing CuBi2O4, the drying is carried out at 60 °C for 12 h.
[0012] The above-mentioned BiOCl / CuBi2O4 composite material is used in the ultrasonic catalytic degradation of organic pollutants in wastewater. The method is as follows: BiOCl / CuBi2O4 composite material is added to wastewater containing organic pollutants, and the wastewater is ultrasonically treated for 1 h in a dark environment at an ultrasonic power of 500 W.
[0013] Furthermore, the above-mentioned BiOCl / CuBi2O4 composite material is used in the ultrasonic catalytic degradation of organic pollutants in wastewater, wherein the amount of BiOCl / CuBi2O4 composite material added is 1 g / L, and the initial concentration of organic pollutants is 50 mg / L.
[0014] The above-mentioned BiOCl / CuBi2O4 composite material is used as an acoustic catalyst in the degradation of organic pollutants in wastewater by activating persulfate. The method is as follows: BiOCl / CuBi2O4 composite material and persulfate are added to wastewater containing organic pollutants, and the wastewater is ultrasonically treated for 2 min in a dark environment with an ultrasonic power of 500 W.
[0015] Furthermore, the above-mentioned BiOCl / CuBi2O4 composite material is used as an acoustic catalyst in the degradation of organic pollutants in wastewater by activating persulfate. The amount of BiOCl / CuBi2O4 composite material added is 1 g / L, the amount of persulfate added is 0.25 g / L, and the initial concentration of organic pollutants is 50 mg / L.
[0016] Preferably, in any of the above applications, the organic pollutant is tetracycline.
[0017] The beneficial effects of this invention are:
[0018] 1. In recent years, CuBi₂O₄, as a novel bismuth-based catalytic material, has attracted widespread attention due to its narrow band gap and wide visible light response range, showing significant potential in photocatalytic water splitting for hydrogen production and pollutant degradation. BiOCl, as a typical bismuth-based halide oxide, possesses a unique layered structure, suitable band edge positions (conduction band approximately -1.1 eV, valence band approximately 3.4 eV), and high chemical stability, complementing the band structure of CuBi₂O₄. Constructing a heterojunction by combining CuBi₂O₄ and BiOCl significantly enhances the interfacial charge separation efficiency, thereby improving the catalytic activity and stability of the composite system.
[0019] 2. The present invention combines the two to obtain 20% BiOCl / CuBi2O4 (abbreviated as CB-20), which is used as an acoustic catalyst for the oxidation and degradation of recalcitrant organic pollutants in wastewater by persulfate. It can significantly improve the catalyst's activity in activating persulfate and greatly enhance the degradation efficiency. Moreover, the catalyst has strong anti-interference ability and high stability, and can be applied to the efficient degradation of a variety of pollutants, providing a new solution for the ultrasonic catalytic treatment of organic pollutants in wastewater.
[0020] 3. In the preparation process of BiOCl / CuBi2O4 composite material, this invention controls the doping degree of BiOCl composite CuBi2O4 by limiting the proportion of key components, thereby changing the catalytic active sites and improving catalytic activity.
[0021] 4. The raw materials for the BiOCl / CuBi2O4 composite material of this invention are abundant and inexpensive, and the synthesis method is simple. As a catalyst, it has good industrialization prospects in the field of advanced oxidation water treatment processes. Attached Figure Description
[0022] Figure 1 The images show the XRD patterns of BiOCl / CuBi2O4 composite materials with different composite ratios obtained in Example 1.
[0023] Figure 2The images are SEM images of CuBi2O4 (a), BiOCl (b), and composite material CB-20 (c) obtained in Example 1, and EDS images (dg) of Bi, Cl, Cu, and O elements of composite material CB-20.
[0024] Figure 3 These are the XPS spectra of CuBi2O4, BiOCl, and the composite material CB-20 obtained in Example 1.
[0025] Figure 4 This is a comparison chart of the adsorption removal efficiency of TC and the synergistic ultrasonic catalytic degradation efficiency of TC by CuBi2O4, BiOCl, and BiOCl / CuBi2O4 composite materials with different composite ratios.
[0026] Figure 5 This is a comparison of the time effects of ultrasonic degradation of TC in different reaction systems.
[0027] Figure 6 The effect of different water bodies on the synergistic ultrasonic catalytic degradation of TC by activated persulfate in the composite material CB-20.
[0028] Specific examples
[0029] The present invention will now be described in detail with reference to the embodiments.
[0030] Example 1
[0031] (I) Preparation of BiOCl / CuBi2O4 composite materials with different composite ratios
[0032] 1) Preparation of CuBi₂O₄: 2.42 g of Cu(NO₃)₂·3H₂O was accurately weighed using an analytical balance and dissolved in 100 mL of deionized water. The solution was stirred continuously for 15 min. Then, 9.7 g of Bi(NO₃)₃·5H₂O was weighed using an analytical balance and added to a copper nitrate solution. The solution was sonicated for 15 min to form a homogeneous suspension. The solution was then placed on a magnetic stirrer, and 50 mL of 1 mol / L NaOH solution was added dropwise under vigorous stirring to adjust the pH to 14. At this point, the suspension gradually turned blue-green. After stirring for 3 h, the solution was transferred to a 100 mL reaction vessel and reacted at 180 ℃ for 5 h. After the reaction was complete, the reaction vessel was cooled to room temperature, washed three times each with anhydrous ethanol and deionized water, and then dried in a vacuum drying oven at 60 ℃ for 12 h. The dried product was then removed and ground to obtain a brownish-red CuBi₂O₄ powder.
[0033] 2) Preparation of BiOCl: 4.85 g of Bi(NO3)3·5H2O and 0.89 g of KCl were accurately weighed using an analytical balance and dissolved in 40 mL of deionized water. The mixture was stirred continuously for 30 min to form a suspension. This solution was transferred to a 100 mL reaction vessel and reacted at 180 ℃ for 9 h. After the reaction was complete, the reaction vessel was cooled to room temperature, washed three times each with anhydrous ethanol and deionized water, and then dried in a vacuum drying oven at 60 ℃ for 12 h. The dried product was then removed and ground to obtain white BiOCl powder.
[0034] 3) Preparation of BiOCl / CuBi2O4 composite material: 545.5 mg of CuBi2O4 powder was accurately weighed and placed in 40 mL of deionized water. The solution was ultrasonicated for 15 min to prepare a homogeneous solution. A certain amount of Bi(NO3)3·5H2O and KCl were added, and the mixture was stirred continuously with a magnetic stirrer for 15 min until a homogeneous solution was obtained. The solution was then transferred to an autoclave reactor and reacted at 180 °C for 9 h. After the reaction was completed, the reactor was cooled to room temperature, washed three times each with anhydrous ethanol and deionized water, and then dried in a vacuum drying oven at 60 °C for 12 h. The resulting dried product, BiOCl / CuBi2O4, was ground and labeled for later use.
[0035] The molar amounts of BiOCl were made to account for 10%, 20%, and 30% of the molar amounts of CuBi₂O₄, respectively. The complexes were named according to the theoretical yield of BiOCl and the percentage of 1 mmol of CuBi₂O₄. For example, if the theoretical yield of BiOCl was 0.2 mmol, the BiOCl / CuBi₂O₄ complex was named CB-20. CB-10, CB-20, and CB-30 were synthesized using this method.
[0036] (II) Characterization of BiOCl / CuBi2O4 composite material
[0037] Figure 1The images show the XRD patterns of BiOCl, CuBi2O4, and BiOCl / CuBi2O4 with different molar ratios. It can be seen that the main diffraction peaks of BiOCl are located at 2θ = 24.15 °, 25.93 °, 33.68 °, 33.54 °, 36.56 °, 41.03 °, 46.83 °, 49.76 °, 55.14 °, 58.74 °, 68.23 °, and 75.05 °, corresponding to the (002), (101), (110), (102), (003), (112), (200), (113), (104), (212), (220), and (124) crystal planes of cubic BiOCl (JCPDS NO. 06-0249). The main diffraction peaks of CuBi₂O₄ are located at 2θ = 20.9 °, 28.0 °, 29.7 °, 30.9 °, 33.3 °, 37.6 °, 46.7 °, 53.0 °, 55.6 °, and 60.7 °, corresponding to the (200), (211), (002), (102), (310), (202), (411), (213), (332), and (521) crystal planes of CuBi₂O₄ (JCPDS NO.72-0493). The CB-20 composite material shows all the diffraction peaks corresponding to CuBi₂O₄ and BiOCl, proving that BiOCl nanoparticles were successfully modified on the CuBi₂O₄ surface.
[0038] Figure 2 These are SEM images and EDS analysis images (dg) of CuBi2O4 (a), BiOCl (b), and the composite material CB-20 (c). Figure 2 (a) It can be seen that the CuBi₂O₄ synthesized by the hydrothermal method has a rod-like shape, a smooth surface, and a length of approximately 3 μm. Figure 2 (b) It can be seen that the synthesized BiOCl exhibits a plate-like structure. Meanwhile, Figure 2 (c) As can be seen, the composite CB-20 synthesized by the two-step hydrothermal method maintains the basic rod-like structure of CuBi2O4, and the BiOCl nanosheets coated on its surface increase the specific surface area of the catalyst. This result indicates that BiOCl has been successfully attached to the surface of CuBi2O4. Figure 2 (d)-(g) show the corresponding elemental mapping of the BiOCl / CuBi2O4 nanocomposite material, further demonstrating that the Bi, Cl, Cu and O elements are uniformly distributed in the composite material, indicating that BiOCl and CuBi2O4 are tightly bonded.
[0039] Figure 3 These are XPS images of CuBi₂O₄, BiOCl, and the composite material CB-20. (The last sentence appears to be incomplete and possibly refers to a technical detail.) Figure 3The full scan spectrum shows that BiOCl / CuBi2O4 clearly contains Bi, Cl, Cu and O elements, which further proves the successful preparation of the composite material.
[0040] Example 2: Synergistic ultrasonic catalytic degradation of TC by BiOCl / CuBi2O4 composite material
[0041] (I) Methods for removing TC by stirring adsorption of elemental BiOCl / CuBi2O4 composite materials with different composite ratios
[0042] Weigh 20 mg of the composite material CB-20 using an analytical balance and add it to a 250 mL Erlenmeyer flask. Add 20 mL of a 50 mg / L tetracycline (TC) solution to the flask. Stir the flask on a magnetic stirrer for 30 min in the dark. After stirring, take a 2 mL sample using a syringe and filter it through a 0.22 μm organic filter membrane to obtain the supernatant. Measure the absorbance using a UV-Vis spectrophotometer and calculate the efficiency of CB-20 in adsorbing and removing TC.
[0043] The adsorption and removal rates of TC by BiOCl, CuBi2O4, CB-10, and CB-30 were determined using the same method, and the removal effects of BiOCl / CuBi2O4 composite materials with different composite ratios were compared in the TC solution.
[0044] (II) A method for synergistic ultrasonic catalytic degradation of TC using BiOCl / CuBi2O4 composite materials with different composite ratios.
[0045] Weigh 20 mg of the composite material CB-20 using an analytical balance and add it to a 250 mL Erlenmeyer flask. Add 20 mL of a 50 mg / L TC solution to the flask. Place the Erlenmeyer flask on an ultrasonic cleaner using an iron stand, ensuring the water level in the cleaner is just touching the bottom of the flask. Use a black plastic bag to provide a dark environment for the reaction and eliminate light interference. Sonicate at 500 W for 60 min. After the reaction, take a 2 mL sample using a syringe, filter it through a 0.22 μm organic filter membrane to obtain the supernatant, and measure the absorbance using a UV spectrophotometer to calculate the ultrasonic degradation efficiency of TC by the composite material CB-20.
[0046] The efficiency of TC degradation by synergistic ultrasonic catalysis of BiOCl, CuBi2O4, CB-10, and CB-30 was determined using the same method, and the removal effect of BiOCl / CuBi2O4 composite materials with different composite ratios in TC solution was compared.
[0047] (III) Testing
[0048] Figure 4This is a comparison of the adsorption removal efficiency of TC and the synergistic ultrasonic catalytic degradation efficiency of BiOCl / CuBi2O4 composite materials with different composite ratios. Figure 4 As shown, the adsorption removal rates of TC by CuBi₂O₄, BiOCl, CB-10, CB-20, and CB-30 were 52.61 ± 2.83%, 14.41 ± 2.21%, 37.14 ± 0.79%, 44.16 ± 0.36%, and 46.28 ± 4.12%, respectively, while the ultrasonic degradation rates of TC were 65.03 ± 2.17%, 46.10 ± 7.95%, 66.22 ± 1.48%, 76.12 ± 2.41%, and 68.91 ± 3.77%, respectively. When BiOCl was combined with CuBi₂O₄, the removal rate of TC by the acoustic catalysis system showed a trend of first increasing and then decreasing, reaching the maximum removal rate at a combination ratio of 20%. The increased removal rate observed when the BiOCl composite ratio increased from 10% to 20% can be attributed to the fact that the addition of BiOCl, which adheres to the surface of CuBi2O4, increases the specific surface area and active sites of the catalyst material. However, a slight excess of BiOCl masks the original reactive sites of CuBi2O4, thereby leading to a decrease in the ultrasonic degradation rate of TC.
[0049] Example 3: Investigation of the time effect of ultrasonic degradation of TC in different reaction systems
[0050] (I) A method for the synergistic ultrasonic catalytic degradation of TC using composite material CB-20
[0051] 20 mg of the composite material CB-20 was weighed using an analytical balance and added to a 250 mL Erlenmeyer flask. 20 mL of a 50 mg / L TC solution was then added to the flask. The Erlenmeyer flask was placed on a metal stand above an ultrasonic cleaner, ensuring the water level in the cleaner was just touching the bottom of the flask. A black plastic bag was used to provide a dark environment for the reaction to eliminate light interference. The mixture was ultrasonically cleaned at 500 W. Samples of 2 mL were taken at 2 min, 4 min, 6 min, and 8 min, and then filtered through a 0.22 μm organic filter membrane to obtain the supernatant. The efficiency of CB-20 in ultrasonic degradation of TC at different time points was calculated.
[0052] (II) A method for the synergistic ultrasonic catalytic degradation of TC using CB-20 composite material activated persulfate.
[0053] 20.0 mg of CB-20 composite material was accurately weighed using an analytical balance and placed in a 250 mL Erlenmeyer flask. 20 mL of a 50 mg / L TC solution was added. 1 mg, 3 mg, 5 mg, 7 mg, and 9 mg of persulfate PMS were added to each reaction system, respectively. The Erlenmeyer flasks were placed on an ultrasonic cleaner using an iron stand, ensuring the water level in the cleaner was just touching the bottom of the flask. A black plastic bag was used to provide a dark environment to eliminate light interference. The mixture was ultrasonicated at 500 W. Samples of 2 mL were taken at 2 min, 4 min, 6 min, and 8 min, and then filtered through a 0.22 μm organic filter to obtain the supernatant. The efficiency of CB-20 in activating PMS and synergistic ultrasonic degradation of TC at different time points was calculated.
[0054] (iv) Testing
[0055] Figure 5 This is a comparison graph showing the time effect of ultrasonic degradation of TC in different reaction systems. (Example) Figure 5 As shown, adding 5 mg of PMS to 20 mg of CB-20 composite material resulted in a removal rate of 94.26 ± 1.03% in just 2 minutes, demonstrating excellent PMS activation ability. Simultaneously, the ultrasonic degradation time was effectively shortened from 1 h to 2 minutes.
[0056] Figure 6 This relates to the impact of TC degradation in different water bodies. For example... Figure 6 As shown, the reaction in real water bodies also demonstrates that the CB-20 composite material activated persulfate synergistic ultrasonic catalytic degradation system is less affected by background substances in the water and can maintain a high TC removal efficiency.
Claims
1. A BiOCl / CuBi2O4 composite material, characterized in that, The BiOCl / CuBi2O4 composite material is made by combining BiOCl with a CuBi2O4 support, wherein the molar amount of BiOCl is 10%-30% of the molar amount of CuBi2O4.
2. The method for preparing a BiOCl / CuBi2O4 composite material according to claim 1, characterized in that, The preparation method is as follows: Bi(NO3)3·5H2O is added to CuBi2O4 suspension and stirred. Then KCl is added and stirred vigorously. The mixed solution is transferred to a high-pressure reactor for hydrothermal reaction. After the reaction is completed, the mixture is filtered, washed, and dried to obtain BiOCl / CuBi2O4 composite material.
3. The preparation method according to claim 2, characterized in that, The hydrothermal reaction conditions were 180°C for 9 hours.
4. The preparation method according to claim 2, characterized in that, The preparation method of CuBi2O4 is as follows: Cu(NO3)2·3H2O is dissolved in deionized water and stirred. While stirring, Bi(NO3)3·5H2O is added to it and ultrasonically mixed. Then, NaOH solution is slowly added under vigorous stirring to obtain a blue-green suspension and continue stirring. After stirring is completed, a hydrothermal reaction is carried out. After the reaction is completed, the mixture is filtered, washed, dried, and ground to obtain CuBi2O4 powder.
5. The preparation method according to claim 4, characterized in that, The hydrothermal reaction conditions were as follows: reaction at 180 °C for 5 h.
6. The preparation method according to claim 2 or 4, characterized in that, The drying process involved drying at 60 °C for 12 h.
7. The application of the BiOCl / CuBi2O4 composite material according to claim 1 as an acoustic catalyst in the degradation of organic pollutants in wastewater by activated persulfate.
8. The application according to claim 7, characterized in that, The organic pollutant is tetracycline.
9. The application according to claim 7 or 8, characterized in that, The application method is as follows: BiOCl / CuBi2O4 composite material and persulfate are added to wastewater containing organic pollutants, and the wastewater is ultrasonically treated in the dark.
10. The application according to claim 9, characterized in that, The BiOCl / CuBi2O4 composite material was added at a concentration of 1 g / L, the persulfate concentration was 0.25 g / L, the initial concentration of organic pollutants was 50 mg / L, the ultrasonic power was 500 W, and the treatment time was 2 min.