Preparation method and application of goethite loaded zero-valent copper activated molecular oxygen catalyst
By preparing goiterite-laden zero-valent copper activated molecular oxygen catalyst, the problem of insufficient catalytic sites is solved, and the catalytic performance is significantly improved and stability is enhanced, which is suitable for efficient degradation of organic wastewater.
Patent Information
- Application Number
- CN202510298740.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-13
- Publication Date
- 2025-07-08
AI Technical Summary
The insufficient number and distribution of catalytic sites of existing goiterite catalysts lead to low catalytic efficiency in the activation of molecular oxygen, and the improvement of existing modification methods is limited.
By preparing goiterite-supported zero-valent copper activated molecular oxygen catalyst, goiterite and zero-valent copper are combined by liquid phase reduction method, and its added amount is regulated to prepare a catalyst with excellent performance and stable performance, expanding the surface area of the reactants at the active site.
It significantly improves catalytic performance, improves catalyst stability, is easy to separate from pollutants, reduces secondary pollution, and achieves efficient degradation of organic wastewater.
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Figure CN120268399A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of advanced oxidation catalytic materials for sewage treatment, and particularly relates to a preparation method and application of a goethite-supported zero-valent copper-activated molecular oxygen catalyst. Background Art
[0002] The water bodies in industrial production contain a large number of harmful organic compounds, which have high drug resistance and are difficult to degrade in biological treatment. Advanced oxidation processes (AOPs) based on activated molecular oxygen are a technology for treating wastewater with high organic load and difficult biodegradation. In the AOPs activation system, the activated molecular oxygen system has been widely studied due to its mild reaction conditions, fast reaction rate, no secondary pollution, wide application range and other advantages.
[0003] Goethite belongs to iron oxide minerals. Due to its high catalytic activity, environmental friendliness, stability and versatility, it has applications in catalysis and environmental remediation. In the advanced oxidation process based on activated molecular oxygen, goethite can be used as a catalyst to activate molecular oxygen to degrade pollutants in water. However, due to the small number and distribution of surface active sites on goethite, its catalytic efficiency is low. To solve these problems, people have begun to study the composite of goethite with other materials to provide a larger surface area for the diffusion of reactants on the active sites and improve its catalytic performance.
[0004] There are reports in the prior art on the activation of ozone by goethite, the oxidation of trivalent arsenic by copper-doped goethite, the degradation of tetracycline by goethite and birnessite, the modification of goethite by boric acid, and the presence of free radical and non-free radical pathways in the degradation of tetracycline by manganese- or zinc-substituted goethite. The existing technologies have insufficient regulation and modification of the catalytic sites of goethite, and there are certain limitations in improving the catalytic activity. Summary of the Invention
[0005] Aiming at the deficiencies of the prior art, the present invention provides a preparation method and application of a goethite-supported zero-valent copper-activated molecular oxygen catalyst.
[0006] In the technical solution of the present invention, iron oxyhydroxide (FeOOH) all refers to goethite.
[0007] The technical solution of the present invention is as follows:
[0008] A preparation method of a goethite-supported zero-valent copper-activated molecular oxygen catalyst, comprising the following steps:
[0009] Hydroxy iron oxide and anhydrous copper sulfate are added to distilled water to obtain a first mixed solution. The first mixed solution is stirred while passing nitrogen. Subsequently, under the conditions of passing nitrogen and stirring, a sodium borohydride solution is added to the first mixed solution for a reduction reaction. After the reaction is completed, solid-liquid separation is carried out, and the reaction product is washed and freeze-dried to obtain a goethite-supported zero-valent copper activated molecular oxygen catalyst.
[0010] Preferably according to the present invention, the mass percentage of the total solute in the first mixed solution is 0.2%-0.8%.
[0011] Preferably according to the present invention, the molar ratio of the hydroxy iron oxide to the anhydrous copper sulfate is 2:(0.5-5).
[0012] More preferably, the molar ratio of the hydroxy iron oxide to the anhydrous copper sulfate is 2:1.
[0013] Preferably according to the present invention, the mass percentage of the sodium borohydride solution is 0.3%-0.4%.
[0014] More preferably, the volume ratio of the added sodium borohydride solution to the volume of the first mixed solution is 1:1.
[0015] Preferably according to the present invention, the time for stirring the first mixed solution while passing nitrogen is more than 0.5 h.
[0016] More preferably, the time for stirring the first mixed solution while passing nitrogen is 0.5-0.7 h.
[0017] Preferably according to the present invention, the sodium borohydride solution is added dropwise to the first mixed solution for a reduction reaction.
[0018] More preferably, the dropping rate of the sodium borohydride solution is 1-2 drops / s.
[0019] Preferably according to the present invention, the stirring time after the addition of the sodium borohydride solution is completed is more than 0.3 h.
[0020] More preferably, the stirring time after the dropping of the sodium borohydride solution is completed is 0.5-0.7 h.
[0021] Preferably according to the present invention, solid-liquid separation is carried out by centrifugation.
[0022] More preferably, the centrifugation speed is 9500-10000 r / min.
[0023] Preferably according to the present invention, the washing process uses distilled water and absolute ethanol to wash 3-5 times in sequence.
[0024] More preferably, the washing time for each time in the washing process is 3-4 minutes.
[0025] Preferably according to the present invention, the freeze-drying time is more than 48 h.
[0026] More preferably, the freeze-drying time is 48 - 50 h.
[0027] Application of the goethite-supported zero-valent copper activated molecular oxygen catalyst prepared by the above method in treating organic wastewater.
[0028] Preferably according to the present invention, application of the goethite-supported zero-valent copper activated molecular oxygen catalyst prepared by the above method in degrading one or more of the organic wastewater pollutants tetracycline, oxytetracycline, p-nitrophenol, sulfamethoxazole, rhodamine B, and norfloxacin.
[0029] The beneficial effects of the present invention at least include the following:
[0030] 1. The goethite-supported zero-valent copper activated molecular oxygen catalyst proposed by the present invention uses a liquid-phase reduction method to compound goethite and zero-valent copper, giving full play to the catalytic performance of both, and obtaining a goethite-supported zero-valent copper activated molecular oxygen catalyst with significantly improved catalytic performance compared to single goethite or zero-valent copper; at the same time, the inventor adjusts the addition amounts of goethite and zero-valent copper during the preparation process to obtain a catalyst with excellent and stable performance.
[0031] 2. The goethite-supported zero-valent copper activated molecular oxygen catalyst proposed by the present invention, by supporting zero-valent copper on goethite, provides a larger surface area for the diffusion of reactants at the active sites while enhancing the stability of goethite, thereby enhancing the catalytic performance of the catalyst; in addition, the compounding of zero-valent copper and goethite can obtain a goethite-supported zero-valent copper activated molecular oxygen catalyst with a size larger than that of goethite, which is thus conducive to subsequent separation from pollutants and reduces secondary pollution of the catalyst. In the above manner, a goethite-supported zero-valent copper activated molecular oxygen catalyst that can be recycled and has high catalytic performance can be simply prepared. Description of the Drawings
[0032] Figure 1 Comparison diagram of the degradation effects of the goethite-supported zero-valent copper activated molecular oxygen catalyst prepared in Example 1 on tetracycline at different FeOOH / Cu 0 molar ratios;
[0033] In the figure: Gt-Cu 0 -0.5, Gt-Cu 0 -1, Gt-Cu 0 -2, Gt-Cu 0 -3, Gt-Cu 0 -4, Gt-Cu 0-5 represent catalysts prepared by combining goethite at 0.02 M with anhydrous copper sulfate at 0.005 M, 0.01 M, 0.02 M, 0.03 M, 0.04 M, and 0.05 M respectively.
[0034] Figure 2 SEM image of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2.
[0035] Figure 3 XPS image of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2.
[0036] Figure 4 Comparison chart of the degradation effect of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2 on tetracycline at different catalyst concentrations.
[0037] Figure 5 Comparison chart of the degradation effect of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2 on tetracycline under different pH conditions.
[0038] Figure 6 Comparison chart of the cyclic degradation effect of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2 on tetracycline under different aeration volumes.
[0039] Figure 7 Comparison chart of the degradation effect of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2 on tetracycline at different concentrations.
[0040] Figure 8 Comparison chart of the degradation effect of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2 and catalysts in different systems on tetracycline;
[0041] In the figure, TC, Gt / air, Cu 0 / air, Gt-Cu 0 -1 / air represent tetracycline, goethite aeration, zero-valent copper aeration, and goethite-supported zero-valent copper catalyst aeration respectively.
[0042] Figure 9 Stability experiment diagram of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2.
[0043] Figure 10 Comparison chart of the degradation effect of the goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2 on different pollutants;
[0044] In the figure: TC is tetracycline, RhB is rhodamine B, MB is methylene blue, OTC is oxytetracycline, PNP is p-nitrophenol, SMX is sulfamethoxazole, and NFX is norfloxacin.
[0045] Figure 11 Comparison diagram of the degradation effect of goethite-supported zero-valent copper-activated molecular oxygen catalyst prepared in Example 2 on tetracycline in different water bodies;
[0046] In the figure: Control is distilled water, Tap Water is tap water, Yellow River is the Yellow River water, Daming Lake is Daming Lake water, and Jiazi Lake is Jiazi Lake water. Specific implementation manners
[0047] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereto.
[0048] The experimental methods used in the following embodiments are all conventional methods unless otherwise specified.
[0049] The materials, reagents, etc. used in the following embodiments can be obtained from commercial channels unless otherwise specified.
[0050] Sources of reagent materials
[0051] Anhydrous copper sulfate (CuSO4), tetracycline (TC), oxytetracycline (OTC), p-nitrophenol (PNP), sulfamethoxazole (SMX), rhodamine B (RhB), norfloxacin (NFX) Shanghai Macklin Biochemical Technology Co., Ltd. (Shanghai, China);
[0052] Methylene blue (MB) Tianjin Damao Chemical Reagent Factory (Tianjin, China);
[0053] Goethite (FeOOH) Shanghai Aladdin Biochemical Technology Co., Ltd. (Shanghai, China) (cas: 20344-49-4);
[0054] Sodium borohydride (NaBH4) Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China).
[0055] Example 1
[0056] A preparation method and degradation experiment of a goethite-supported zero-valent copper-activated molecular oxygen catalyst, including the following steps:
[0057] S1. Weigh 0.0889 g of FeOOH and anhydrous copper sulfate with different masses of 0.0399 g, 0.0798 g, 0.1596 g, 0.2394 g, 0.3192 g, and 0.3990 g respectively, and dissolve them in 50 mL of distilled water to obtain mixed solutions with different molar concentration combinations, namely mixed solutions of 0.02 M FeOOH combined with 0.005 M, 0.01 M, 0.02 M, 0.03 M, 0.04 M, and 0.05 M anhydrous copper sulfate. After introducing N2 into the solution and magnetically stirring for 30 min to mix evenly, under the stirring condition of introducing N2, 50 mL of 0.1 M sodium borohydride solution (0.1895 g) is slowly added dropwise to the above mixed solution at a rate of 1 - 2 drops / s. After the addition, continue stirring for 30 min, and perform solid-liquid separation by centrifugation at 10000 r / min for 3 min. Wash the reaction product with deionized water and anhydrous ethanol 3 times respectively, 3 minutes each time, and freeze-dry for 48 h to prepare goethite-supported zero-valent copper activated molecular oxygen catalysts with 6 different molar ratios.
[0058] In the described preparation method, nitrogen is introduced to prevent the oxidation of materials during the reaction process.
[0059] S2. At room temperature, add 95 mL of distilled water to 5 mg of the catalysts with different molar ratios prepared in step S1 respectively, and mix them with 5 mL of 200 mg / L tetracycline (TC) solution, which are respectively denoted as n = 0.5, 1, 2, 3, 4, 5 (0.5 represents the combination of 0.02 M FeOOH and 0.005 M anhydrous copper sulfate, 1 represents the combination of 0.02 M FeOOH and 0.01 M anhydrous copper sulfate, 2 represents the combination of 0.02 M FeOOH and 0.02 M anhydrous copper sulfate, 3 represents the combination of 0.02 M FeOOH and 0.03 M anhydrous copper sulfate, 4 represents the combination of 0.02 M FeOOH and 0.04 M anhydrous copper sulfate, 5 represents the combination of 0.02 M FeOOH and 0.05 M anhydrous copper sulfate). After adjusting the pH of the above mixed solution to 7.0 ± 0.1 with sodium hydroxide and hydrochloric acid, then perform aeration at 2 L / min to start the degradation experiment. The experiment is carried out under the condition of magnetic stirring. By testing the change of the ultraviolet absorption spectrum (wavelength is 357 nm) of the solution, it shows the degradation effect of catalysts with different FeOOH / Cu 0 molar ratios on tetracycline.
[0060] In order to explore the degradation rate of the goethite-supported zero-valent copper activated molecular oxygen catalyst prepared in this example on tetracycline, the degradation test is carried out by the steps of S2, and the results are shown in Figure 1, after reacting for 30 min, good degradation effects were achieved when n = 0.5, 1, 2, 3, and 4, which were 91.3%, 95.8%, 92.7%, 84.2%, and 89.9% respectively, and the degradation rate was 70.7% when n = 5. The degradation effect was the best when n = 1, with a degradation rate of 95.8%. In subsequent experiments, the catalyst corresponding to the molar ratio when n = 1 (i.e., the combination of 0.02M FeOOH and 0.01M anhydrous copper sulfate) will also be used for experiments.
[0061]
[0062] In the formula, C is the concentration of tetracycline at a certain reaction time, and C0 is the initial concentration of tetracycline.
[0063] Example 2
[0064] The catalyst was prepared according to the method described in Example 1.
[0065] Specifically: 0.0889 g of FeOOH and 0.0798 g of anhydrous copper sulfate were respectively weighed and dissolved in 50 mL of distilled water to obtain a mixed solution (i.e., the combination of 0.02M FeOOH and 0.01M anhydrous copper sulfate). After introducing N2 into the solution and magnetically stirring for 30 min to mix evenly, under the condition of introducing N2 and stirring, 50 ml of 0.1M sodium borohydride solution (0.1895 g) was slowly dropped into the above mixed solution at a rate of 1 - 2 drops / s. After the dropping was completed, stirring was continued for 30 min, followed by solid-liquid separation and centrifugation at 10000 r / min for 3 min. The reaction product was washed 3 times with deionized water and anhydrous ethanol respectively, 3 minutes each time, and then freeze-dried for 48 h to obtain goethite-supported zero-valent copper-activated molecular oxygen catalyst (Gt-Cu 0 -1).
[0066] The SEM image and XPS image of the obtained goethite-supported zero-valent copper-activated molecular oxygen catalyst (Gt-Cu 0 -1) are shown in Figure 2 , Figure 3 .
[0067] Figure 2 is the SEM image of the catalyst (Gt-Cu 0 -1), Figure 3 is the XPS image of the catalyst (Gt-Cu 0 -1). The peak of zero-valent copper shown in the figure is 932.6.
[0068] Example 3
[0069] The different concentrations of the goethite-supported zero-valent copper-activated molecular catalyst on the degradation effect are as follows:
[0070] Using the goethite-supported zero-valent copper-activated molecular oxygen catalyst (Gt-Cu 0 -1) prepared in Example 2 for the experiment.
[0071] At room temperature, 95 mL of distilled water was added to 2 mg, 5 mg, and 10 mg of catalysts (Gt-Cu 0 -1) with different concentrations respectively, and each was mixed with 5 mL of 200 mg / L tetracycline (TC) solution. Other conditions were the same as those in the test conditions of S2 in Example 1 to detect the degradation effect of tetracycline with different catalyst dosages.
[0072] The results showed that the catalyst prepared in the present invention had the highest degradation rate for TC under the condition of 50 mg / L concentration, as shown in Figure 4 Subsequently, a catalyst dosage of 50 mg / L will be adopted in the following experiments.
[0073] Example 4
[0074] The degradation effect of the goethite-supported zero-valent copper-activated molecular catalyst under different pH conditions is as follows:
[0075] Using the goethite-supported zero-valent copper-activated molecular oxygen catalyst (Gt-Cu 0 -1) prepared in Example 2 for the experiment.
[0076] At room temperature, 95 mL of distilled water was added to 5 mg of the catalyst (Gt-Cu 0 -1) and mixed with 5 mL of 200 mg / L tetracycline (TC) solution. The pH of the above mixture was adjusted to 4.0, 5.0, 6.0, 7.0, 8.0, 9.0 ± 0.1 with sodium hydroxide and hydrochloric acid respectively. Other conditions were the same as those in the test conditions of S2 in Example 1 to detect the degradation effect of the catalyst on tetracycline at different pH values. The degradation rates were 75.8%, 86.4%, 92.1%, 95.8%, 93.3%, and 76.0% respectively.
[0077] The results showed that Figure 5 It can be seen that the catalyst (Gt-Cu 0 -1) had good degradation effects under both acidic pH 4 (degradation rate of 75.8%) and alkaline pH 9 (degradation rate of 76%) conditions, indicating that the catalyst had a wide pH adaptation range.
[0078] The catalyst prepared in the present invention had the highest degradation rate for TC under the condition of pH 7.0 ± 0.1, as shown in Figure 5 Subsequently, the following experiments will be carried out under the condition of pH = 7.0 ± 0.1.
[0079] Example 5
[0080] The degradation effect of goethite-supported zero-valent copper-activated molecular oxygen catalyst under different aeration conditions is as follows:
[0081] The goethite-supported zero-valent copper-activated molecular oxygen catalyst (Gt-Cu 0 -1) prepared in Example 2 was used for the experiment.
[0082] At room temperature, 95 mL of distilled water was added to 5 mg of the catalyst (Gt-Cu 0 -1) and 5 mL of 200 mg / L tetracycline (TC) solution. After adjusting the pH of the above mixture to 7.0 ± 0.1 with sodium hydroxide and hydrochloric acid, aeration was carried out at 1, 2, and 3 L / min respectively, and other conditions were the same as the test conditions of S2 in Example 1. The degradation effect of the catalyst on tetracycline at different aeration rates was detected.
[0083] The results showed that the catalyst (Gt-Cu 0 -1) had a higher degradation rate of TC at an aeration rate of 2 L / min. See Figure 6 Subsequent experiments will be carried out under the condition of an aeration rate of 2 L / min.
[0084] Example 6
[0085] The degradation effect of goethite-supported zero-valent copper-activated molecular oxygen catalyst on tetracycline with different concentrations is as follows:
[0086] The goethite-supported zero-valent copper-activated molecular oxygen catalyst (Gt-Cu 0 -1) prepared in Example 2 was used for the experiment.
[0087] At room temperature, 95, 90, 85, and 80 mL of distilled water were added to 5 mg of the catalyst (Gt-Cu 0 -1) and 5, 10, 15, and 20 mL of 200 mg / L tetracycline (TC) solution respectively. Other conditions were the same as the test conditions of S2 in Example 1. The degradation effect of the catalyst on tetracycline with different concentrations was detected.
[0088] The results showed that the catalyst prepared in the present invention had the highest degradation rate for 10 mg / L TC. See Figure 7 Subsequent experiments will be carried out under the condition of a tetracycline concentration of 10 mg / L.
[0089] Example 7
[0090] The degradation effect of different catalysts on tetracycline is as follows:
[0091] The catalysts used were: goethite, zero-valent copper, and the catalyst (Gt-Cu 0 -1) prepared in Example 2.
[0092] At room temperature, 95 mL of distilled water was added without any catalyst (TC =), with 5 mg of zero-valent copper (Cu 0 ), 5 mg of goethite (Gt), and 5 mg of the catalyst (Gt-Cu 0 -1), and mixed with 5 mL of 200 mg / L tetracycline (TC) solution. Other conditions were the same as those in S2 of Example 1 for testing, and the degradation effects of different catalysts on tetracycline were detected.
[0093] Zero-valent copper (Cu 0 ): 0.1596 g of anhydrous copper sulfate was dissolved in 50 mL of distilled water. After passing N2 into the solution and stirring magnetically for 30 min to mix evenly, under the stirring condition of passing N2, 50 mL of 0.1895 g sodium borohydride solution was added dropwise into the above mixed solution at a rate of 1-2 drops / s. After the addition, stirring was continued for 30 min, followed by solid-liquid separation and centrifugation at 10000 r / min for 3 min. The reaction product was washed 3 times with deionized water and anhydrous ethanol respectively, 3 minutes each time, and freeze-dried for 48 h.
[0094] The results showed that the catalyst prepared in the present invention had the highest degradation rate for TC, as shown in Figure 8 , and the degradation effect far exceeded that of each component catalyzed alone. The degradation rates were TC = 3.5%, Cu 0 = 78.5%, Gt = 67.4%, Gt-Cu 0 -1 = 95.8%.
[0095] Example 8
[0096] Recycling stability experiment of goethite-supported zero-valent copper activated molecular oxygen catalyst was carried out as follows:
[0097] The goethite-supported zero-valent copper activated molecular oxygen catalyst (Gt-Cu 0 -1) prepared in Example 2 was used for the experiment.
[0098] (1) At room temperature, 95 mL of distilled water was added with 5 mg of the catalyst (Gt-Cu 0 -1) and mixed with 5 mL of 200 mg / L tetracycline (TC) solution. Other conditions were the same as those in S2 of Example 1 for testing, and the degradation effect of the catalyst on tetracycline was detected after 60 min of reaction.
[0099] (2) The catalyst in step (1) was separated by centrifugation, and needed to be washed 3 times with distilled water and 3 times with ethanol, and then freeze-dried for 48 h. Subsequently, the second degradation experiment was carried out according to step (1). A total of 5 degradation experiments were carried out, which were recorded as 1st, 2nd, 3rd, 4th, and 5th respectively. The final results showed that Figure 9, the performance of this catalyst does not decline significantly and has good stability. It still has a degradation rate of more than 80% in the last degradation experiment. The degradation rates are 96.9% for the 1st, 95.1% for the 2nd, 93.9% for the 3rd, 91.8% for the 4th, and 87.3% for the 5th respectively.
[0100] Example 9
[0101] The degradation effects of goethite-supported zero-valent copper-activated molecular oxygen catalyst on different pollutants are as follows:
[0102] Use the goethite-supported zero-valent copper-activated molecular oxygen catalyst (Gt-Cu 0 -1) prepared in Example 2 for the experiment.
[0103] At room temperature, add 95 mL of distilled water to 5 mg of the catalyst (Gt-Cu 0 -1) and mix it with 5 mL of 200 mg / L solutions of tetracycline (TC), rhodamine B (RhB), methylene blue (MB), oxytetracycline (OTC), p-nitrophenol (PNP), sulfamethoxazole (SMX), and norfloxacin (NFX) respectively. After adjusting the pH of the above mixture to 7.0 ± 0.1 with sodium hydroxide and hydrochloric acid, then conduct aeration at 2 L / min to start the degradation experiment. The experiment is carried out under magnetic stirring conditions for 30 min. By testing the changes in the ultraviolet absorption spectrum of the solution, the degradation effects of the catalyst on different pollutants are detected.
[0104] For tetracycline at 357 nm, rhodamine B at 554 nm, methylene blue at 664 nm, oxytetracycline at 355 nm, p-nitrophenol at 318 nm, sulfamethoxazole at 257 nm, and norfloxacin at 273 nm.
[0105] The results show that the catalyst prepared by the present invention has the highest degradation rate for TC Figure 10 , reaching 95.8%, and the degradation effect is relatively close to that of OTC, far exceeding other pollutants.
[0106] Example 10
[0107] The degradation effects of goethite-supported zero-valent copper-activated molecular oxygen catalyst in different water qualities are as follows:
[0108] Use the goethite-supported zero-valent copper-activated molecular oxygen catalyst (Gt-Cu 0 -1) prepared in Example 2 for the experiment.
[0109] At room temperature, 5 mg of the catalyst (Gt-Cu 0 -1) was added to 95 mL of distilled water (Control), tap water, Yellow River water, Daming Lake water, and Jiazi Lake water respectively, and mixed with 5 mL of 200 mg / L tetracycline (TC) solution. After adjusting the pH of the above mixture to 7.0 ± 0.1 with sodium hydroxide and hydrochloric acid, other conditions were the same as those in S2 of Example 1, and the reaction was carried out for 30 min. The degradation effects of the catalyst in different water qualities were detected, as shown in Figure 11 . The degradation rates were 95.8% for distilled water, 81.4% for tap water, 71.2% for Yellow River water, 85.6% for Daming Lake water, and 80.9% for Jiazi Lake water.
[0110] The results show that the catalyst prepared by the present invention is applicable to various water qualities and has a good degradation effect. It has the potential to degrade pollutants in actual water bodies.
[0111] In summary, for the preparation method of the goethite-supported zero-valent copper activated molecular oxygen catalyst proposed by the present invention, by combining goethite and zero-valent copper, the catalytic performance of both can be fully exerted, so that the finally prepared catalyst shows more excellent catalytic performance; the introduced zero-valent copper is coated on the outer surface of goethite, and finally a goethite-supported zero-valent copper activated molecular oxygen catalyst with a size larger than that of goethite is obtained, which is beneficial to subsequent separation from pollutants and reduces the secondary pollution of the catalyst. Therefore, the catalytic performance of the finally prepared catalyst is better than that of single goethite or zero-valent copper. Through the above method, a goethite-supported zero-valent copper activated molecular oxygen catalyst with high catalytic performance can be simply prepared.
Claims
1. A preparation method of a goethite-supported zero-valent copper-activated molecular oxygen catalyst, characterized in that, It includes the following steps: Add iron oxyhydroxide and anhydrous copper sulfate into distilled water to obtain a first mixed solution. Stir the first mixed solution while introducing nitrogen. Subsequently, under the conditions of introducing nitrogen and stirring, add a sodium borohydride solution to the first mixed solution for a reduction reaction. After the reaction ends, perform solid-liquid separation, and wash and freeze-dry the reaction product to obtain a goethite-supported zero-valent copper activated molecular oxygen catalyst.
2. The method according to claim 1, wherein The mass percentage of the total solute in the first mixed solution is 0.2% - 0.8%; Preferably, the molar ratio of the iron oxyhydroxide to the anhydrous copper sulfate is 2:(0.5 - 5); Preferably, the molar ratio of the iron oxyhydroxide to the anhydrous copper sulfate is 2:
1.
3. The method according to claim 1, characterized in that, The mass percentage of the sodium borohydride solution is 0.3% - 0.4%; Preferably, the volume ratio of the added sodium borohydride solution to the volume of the first mixed solution is 1:
1.
4. The method according to claim 1, wherein The time for stirring the first mixed solution while introducing nitrogen is more than 0.5 h; Preferably, the time for stirring the first mixed solution while introducing nitrogen is 0.5 - 0.7 h.
5. The method according to claim 1, wherein Dropwise add the sodium borohydride solution to the first mixed solution for a reduction reaction; Preferably, the dropping rate of the sodium borohydride solution is 1 - 2 drops / s.
6. The method according to claim 1, characterized in that, The time for continuous stirring after the addition of the sodium borohydride solution is more than 0.3 h; Preferably, the time for continuous stirring after the dropping of the sodium borohydride solution is 0.5 - 0.7 h.
7. The method according to claim 1, wherein Perform solid-liquid separation by centrifugation; Preferably, the centrifugation speed is 9500 - 10000 r / min.
8. The method according to claim 1, wherein In the washing process, wash with distilled water and anhydrous ethanol successively for 3 - 5 times; Preferably, the washing time for each time in the washing process is 3 - 4 minutes.
9. The method according to claim 1, wherein The time for freeze-drying is more than 48 h; Preferably, the time for freeze-drying is 48 - 50 h.
10. Application of the goethite-supported zero-valent copper activated molecular oxygen catalyst prepared by the method according to any one of claims 1 - 9 in treating organic wastewater; Preferably, application of the goethite-supported zero-valent copper activated molecular oxygen catalyst prepared by the method in degrading one or more of the organic wastewater pollutants tetracycline, oxytetracycline, p-nitrophenol, sulfamethoxazole, rhodamine B, and norfloxacin.