Preparation method of a biomimetic ecological floating bed

Abstract

This invention discloses a method for preparing a biomimetic ecological floating bed, comprising the following steps: preparing CoO x / Mo:BiVO4 / Pd photocatalyst powder; preparation of FeOCl adsorption and Fenton-like catalyst powders; the prepared catalyst powders were added as additives to polymers Poly and DMF to form CoO2. x / Mo:BiVO4 / Pd-Poly / DMF and FeOCl-Poly / DMF casting solution; FeOCl-PVDF film is formed in one pass using an automatic coating machine and dried in situ using a dryer; CoO is directly coated onto the FeOCl-PVDF film. x A CoOx / Mo:BiVO4 / Pd-poly / DMF casting solution is used, and an automatic coating device is used to scrape the film a second time to form a CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane. After the CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane is allowed to stand, it is placed in ultrapure water to fully react and complete the phase transformation process, forming a biomimetic ecological floating bed.

Description

Technical Field

[0001] This invention belongs to the field of environmental pollution control engineering, and in particular relates to a method for preparing a biomimetic ecological floating bed. Background Technology

[0002] Ecological floating bed technology is a green and energy-saving in-situ ecological treatment technology mainly composed of floating bodies, substrates, and plants. Emergent plants grow on the floating bodies, with their stems and leaves remaining above the water surface, fully utilizing solar energy for photosynthesis and respiration. Their roots are fixed to the substrate, penetrating the floating bodies and extending into the water, forming a lush underwater root system. This constitutes a natural filtration system, absorbing pollutants from the water into the plants, where a series of oxidation-reduction reactions occur to degrade pollutants and purify the water.

[0003] However, ecological floating beds still have problems such as low efficiency in degrading pollutants and great susceptibility to environmental factors.

[0004] Therefore, based on the principle of pollutant degradation by ecological floating beds and its current problems, a biomimetic ecological floating bed is designed. The floating bed consists of two layers. The upper layer is a photocatalytic layer, similar to the function of plant stems and leaves. Through photocatalytic reactions, it absorbs natural light energy and excites the photocatalyst in the photocatalytic layer to generate holes and photogenerated electrons, using H2O and O2 to generate H2O2 in situ. The lower layer of the double membrane is an adsorption and degradation layer, similar to the function of plant roots. It uses polymers with adsorption properties to enrich pollutants in the water and receives H2O2 generated in the upper layer. Through FeOCl-triggered Fenton-like reactions, it generates H2O2. · OH, · OH radicals react with the enriched pollutants to form free radicals, causing the pollutants to be oxidized or mineralized. This biomimetic ecological floating bed can greatly improve the utilization efficiency of natural light and the removal efficiency of pollutants in water bodies, reducing the impact of environmental factors on the pollutant removal process, which is of great significance for environmental restoration and protection. Summary of the Invention

[0005] The purpose of this application is to address existing water pollution control problems by providing a method for preparing a biomimetic ecological floating bed. We propose a biomimetic ecological floating bed based on the principle of removing pollutants from water. Under natural light conditions, CoO... x The / Mo:BiVO4 / Pd-PVDF film absorbs photons to catalyze the in-situ generation of H2O2, which is then transferred to the FeOCl-PVDF film to undergo a Fenton-like reaction to produce... ·OH, thereby degrading pollutants adsorbed from the water by the polymer PVDF. This biomimetic material pollutant removal principle provided by the present invention offers a new approach for the in-situ efficient degradation of pollutants in water, and deepens our understanding of the efficient removal of pollutants from water by photocatalysis combined with Fenton-like reactions. It helps improve the utilization rate of natural light, reduce pollutant treatment costs, and achieve more significant results in environmental remediation, possessing strong practicality and promotional value.

[0006] According to a first aspect of the embodiments of this application, a method for preparing a biomimetic ecological floating bed is provided, comprising:

[0007] (1) Preparation of CoO x / Mo:BiVO4 / Pd photocatalyst powder;

[0008] (2) Preparation of FeOCl adsorption and Fenton-like catalyst powder;

[0009] (3) The catalyst powders prepared in steps (1) and (2) are added as additives to polymer Poly and DMF to form CoO. x / Mo:BiVO4 / Pd-Poly / DMF and FeOCl-Poly / DMF casting solutions;

[0010] (4) Based on FeOCl-Poly / DMF casting solution, FeOCl-PVDF film is formed by automatic coating machine in one scraping process and then dried in situ using dryer;

[0011] (5) Directly cover the FeOCl-PVDF membrane with CoO x / Mo:BiVO4 / Pd-poly / DMF casting solution, automatic coating device for secondary coating to form CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane;

[0012] (6) After the CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane is left to stand, it is placed in ultrapure water to fully react and complete the phase transformation process, forming a biomimetic ecological floating bed.

[0013] Furthermore, in step (1), CoO is deposited in stages using photodeposition. x / Mo:BiVO4 and CoO x / Mo:BiVO4 / Pd.

[0014] Further, step (1) specifically involves: adding NaIO3, Co(NO3)2, and Mo:BiVO4 to the photoreaction container in a mass ratio of (600±10):(2.25±0.05):(1000±20); introducing N2 into the photoreaction container to create an oxygen-free environment; and using visible light with a wavelength greater than 420 nm under oxygen-free conditions to fully deposit the Mo:BiVO4 photocatalyst powder; washing the powder to remove excess NaIO3 from the solution; and filtering and drying to obtain CoO2. x / Mo:BiVO4 photocatalyst powder; Na2PdCl4 and CoO x / Mo:BiVO4 photocatalyst powder was added to a photoreaction vessel at a mass ratio of (4±1) mg:(1±0.01) g. An oxygen-free environment was created by purging with N2. Under oxygen-free conditions, visible light was used for complete deposition. The resulting product was then filtered and dried to obtain CoO. x / Mo:BiVO4 / Pd photocatalyst powder.

[0015] Further, step (2) specifically involves: placing 2.0±0.2g FeCl3·6H2O in a 20ml or 50ml covered porcelain crucible, adding 10±1ml of anhydrous ethanol, evaporating to dryness at 60±5℃ and 500±50rpm, placing it in a vacuum oven for at least 12h, and then heating it to 220℃ in a muffle furnace at a heating rate of 10±1℃ / min to fully react and obtain FeOCl adsorption and Fenton-like catalyst powder.

[0016] Further, step (3) specifically involves taking 850±20mg Poly and 100±5mg CoO. x / Mo:BiVO4 / Pd powder and 4.26±0.05ml DMF were reacted completely at 60±5℃ and 500±50rpm to form CoO. x / Mo:BiVO4 / Pd-Poly / DMF casting solution; Take 850±20mg Poly, 50±1mg FeOCl powder and 4.26±0.05ml DMF, and react them fully at 60±5℃ and 500±50rpm to form FeOCl-Poly / DMF casting solution.

[0017] Further, step (4) specifically involves: uniformly pouring the FeOCl-Poly / DMF casting solution onto the starting end of the scraper of the automatic coating machine, setting the film thickness to 200±10μm, and scraping the film at a speed of 50±5mm / s to form a FeOCl-PVDF film in one pass.

[0018] Further, step (5) specifically involves: transferring CoO xThe / Mo:BiVO4 / Pd-Poly / DMF casting solution was uniformly poured onto the starting end of the FeOCl-PVDF membrane, and the membrane thickness was set to 500±20μm. The membrane was then scraped a second time at a speed of 50±5mm / s to form a CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane.

[0019] According to a second aspect of the embodiments of this application, a biomimetic ecological floating bed is provided, which is prepared by the method described in the first aspect.

[0020] The technical solutions provided by the embodiments of this application may include the following beneficial effects:

[0021] As can be seen from the above embodiments, this application provides a method for preparing a biomimetic ecological floating bed, which can effectively degrade pollutants in water. This method allows for the artificial manipulation of the natural process of plants absorbing, accumulating, and degrading water pollutants. The development of this technology will contribute to water pollution control and prevention, improve the degradation efficiency of water pollutants, reduce the impact of environmental factors on pollution control processes, and achieve more significant results in environmental remediation. The method provided by this invention is the first to utilize CoO... x By combining Mo:BiVO4 / Pd photocatalyst materials with FeOCl-type Fenton materials, without adding any foreign substances, pollutants in water can be degraded in situ directly using natural light, H2O, and O2 from the air. This provides a new design approach for water pollution control and prevention in the field of photocatalysis.

[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0024] Figure 1 This is a diagram illustrating the mechanism of pollutant degradation by a biomimetic ecological floating bed according to an exemplary embodiment.

[0025] Figure 2 This is a flowchart illustrating the specific operation steps of the biomimetic ecological floating bed film formation process according to an exemplary embodiment.

[0026] Figure 3 The biomimetic ecological floating bed upper layer CoO shown according to an exemplary embodiment x A schematic diagram of the actual film formed by / Mo:BiVO4 / Pd-PVDF and the underlying FeOCl-PVDF.

[0027] Figure 4This is a biomimetic ecological floating bed product illustrated according to an exemplary embodiment. · OH cumulative time verification graph.

[0028] Figure 5 This is a time-cumulative verification diagram of H2O2 production by a biomimetic ecological floating bed, illustrated according to an exemplary embodiment.

[0029] Figure 6 This is a graph illustrating the detection of atenolol adsorption capacity on a biomimetic floating bed according to an exemplary embodiment. Detailed Implementation

[0030] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application.

[0031] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0032] It should be understood that although the terms first, second, third, etc., may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0033] Figure 1 This is a diagram illustrating the mechanism of pollutant degradation by a biomimetic floating bed according to an exemplary embodiment, such as... Figure 1 As shown, the CoO2 in the upper membrane layer of this biomimetic ecological floating bed x The / Mo:BiVO4 / Pd photocatalyst absorbs natural light, generating electron-hole pairs through photoelectron absorption. These pairs then undergo redox reactions at the valence and conduction bands using H2O and O2, respectively, to produce H2O2. The generated H2O2 subsequently diffuses into the FeOCl adsorption and degradation layer of the lower layer of the floating bed, reacting with FeOCl to trigger a Fenton-like reaction. · OH; Finally, PVDF and FeOCl adsorb pollutants in the water onto the FeOCl-PVDF layer. ·OH degradation and mineralization.

[0034] Figure 2 This is a detailed operation flowchart illustrating the biomimetic ecological floating bed film formation steps according to an exemplary embodiment. After preparing the required casting solution, the FeOCl-Poly / DMF casting solution is first poured onto a prepared automatic applicator, with the applicator speed set to 50 mm / s and the film thickness to 200 nm. Automatic film formation is then performed, followed by drying with a dryer for 30 seconds. Subsequently, CoO... x The / Mo:BiVO4 / Pd-Poly / DMF casting solution was uniformly poured onto the starting end of the FeOCl-PVDF membrane. The membrane thickness was set to 500 μm, and the membrane was scraped in one pass at a speed of 50 mm / s to form a CoO4-based membrane. x A biomimetic floating bed of / Mo:BiVO4 / Pd-FeOCl-PVDF is used, and after the double membrane is formed, it is immersed in ultrapure water to carry out the phase transformation process.

[0035] The preparation process specifically includes the following steps:

[0036] (1) Preparation of CoO x / Mo:BiVO4 / Pd photocatalyst powder;

[0037] CoO was deposited in stages using photodeposition. x And Pd. Specifically: 600 mg NaIO3, 1.5 ml Co(NO3)2 and 1.0 g Mo:BiVO4 were added to the photoreaction vessel, N2 was passed through for 20 min, and then the reaction was carried out under anaerobic conditions using visible light (λ>420 nm) for 12-24 h. The powder was washed to remove excess NaIO3 from the solution, and finally filtered and dried to obtain CoO. x / Mo:BiVO4 photocatalyst powder. Subsequently, Na2PdCl4 and CoO x / Mo:BiVO4 photocatalyst powder was added to a photoreaction vessel, and after purging with N2 for 20 min, deposition was carried out under oxygen-free conditions using visible light (λ>420nm) for 12-24 h. Finally, the product was filtered and dried to obtain CoO. x The Mo:BiVO4 / Pd photocatalyst powder contained Co(NO3)2 at a concentration of 1.5 g / L and Na2PdCl4 at a concentration of 3.3 g / L. The addition of NaIO3 acted as a hole trap, allowing Co(NO3)2 to be directionally loaded onto the 110 surface of Mo:BiVO4. The above-mentioned concentration of Pd was verified to be the optimal concentration for hydrogen peroxide production.

[0038] (2) Preparation of FeOCl adsorption and Fenton-like catalyst powder;

[0039] Specifically, 2.0 g of FeCl3·6H2O was placed in a 20 ml covered porcelain crucible, and 10 ml of anhydrous ethanol was added. The mixture was evaporated to dryness at 60℃ and 500 rpm, then placed in a vacuum oven for 12 h. Next, the mixture was heated in a muffle furnace to 220℃ at a rate of 10℃ / min and reacted for 2 h to obtain FeOCl adsorption and Fenton-like catalyst powder. At temperatures above 220℃, FeCl3 can be converted to FeOCl, and tests showed that most of the FeCl3 had been converted to FeOCl after 2 h.

[0040] (3) The catalyst powders from (1) and (2) are added as additives to Poly (polyvinylidene fluoride) and DMF (N,N-dimethylformamide) to form CoO. x / Mo:BiVO4 / Pd-Poly / DMF and FeOCl-Poly / DMF casting solutions;

[0041] Specifically: 850mg Poly, CoO x 100 mg of / Mo:BiVO4 / Pd powder and 4.26 ml of DMF were placed in a 20 ml glass bottle and reacted at 60 °C and 550 rpm for 24 h to form CoO. x / Mo:BiVO4 / Pd-Poly / DMF casting solution: 850 mg Poly, 50 mg FeOCl powder, and 4.26 ml DMF were placed in a 20 ml glass bottle and reacted at 60℃ and 550 rpm for 24 h to form a FeOCl-Poly / DMF casting solution. After 24 h of reaction, the casting solution was basically fully mixed and ready for film formation.

[0042] (4) Based on FeOCl-Poly / DMF casting solution, FeOCl-PVDF film is formed by automatic coating device in one scraping process, and then dried in situ for 30s using a dryer.

[0043] Specifically, the FeOCl-Poly / DMF casting solution is evenly poured onto the starting end of the automatic coating machine's scraper. The film thickness is set to 200 μm, and the FeOCl-PVDF film is formed in a single scraping operation at a speed of 50 mm / s. It is important to note that both the film thickness and scraping speed should be adjusted according to the actual film formation requirements. Thickness primarily affects the content of substances within the film, while speed affects the pore structure and other components.

[0044] (5) Directly cover the FeOCl-PVDF membrane with CoO x / Mo:BiVO4 / Pd-poly / DMF casting solution, automatic coating device for secondary coating to form CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane;

[0045] Specifically: CoOx The Mo:BiVO4 / Pd-Poly / DMF casting solution is uniformly poured onto the starting end of the FeOCl-PVDF membrane. The membrane thickness is set to 500 μm, and a second coating process is performed at a speed of 50 mm / s to form a CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane. It is important to note that both the coating thickness and speed should be adjusted according to the actual membrane formation requirements. Thickness primarily affects the content of substances within the membrane, while speed affects the membrane's pore structure.

[0046] (6) After the CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane is left to stand for at least 30 seconds, it is placed in ultrapure water and reacted for 24 hours to complete the phase transformation process and finally form a biomimetic ecological floating bed. The phase transformation process mainly utilizes the casting liquid to carry out solvent and non-solvent mass transfer exchange with the surrounding environment. The original stable solution becomes unstable and liquid-liquid phase is transformed into two phases: the polymer-rich phase that finally forms the membrane and the polymer-poor phase that forms the pores. Finally, the membrane structure is solidified.

[0047] This application also provides a biomimetic ecological floating bed prepared by the above method.

[0048] Figure 3 The biomimetic ecological floating bed upper layer CoO shown according to an exemplary embodiment x A schematic diagram of the actual film formation of / Mo:BiVO4 / Pd-PVDF and the lower FeOCl-PVDF layer. It can be seen that the upper layer of the bilayer exhibits the predominantly bright yellow color of Mo:BiVO4; the lower layer of the bilayer exhibits a dark reddish-black color, with the degree of blackness mainly influenced by FeOCl.

[0049] Figure 4 This is a cumulative time verification graph illustrating the H2O2 production of a biomimetic ecological floating bed according to an exemplary embodiment. The results show that under natural light and natural air circulation conditions, this biomimetic ecological floating bed produces 377.5 μM H2O2 within 1 hour, after which the production level stabilizes. This effectively demonstrates that this biomimetic ecological floating bed can spontaneously generate H2O2 in situ using natural photocatalysis.

[0050] Figure 5 This is a biomimetic ecological floating bed product illustrated according to an exemplary embodiment. · OH time-cumulative verification graph. The results show that the biomimetic ecological floating bed in the dark group produces almost no OH. · OH, while under natural light conditions, CoO x The upper layer of the / Mo:BiVO4 / Pd-FeOCl-PVDF membrane can generate a cumulative 1692.43 nM within 3 hours. · OH. This effectively demonstrates that FeOCl in the bilayer membrane can catalyze the reaction of H2O2 to produce... · OH.

[0051] Figure 6 This is a graph illustrating the detection of ATL (atenolol) adsorption capacity on a biomimetic ecological floating bed according to an exemplary embodiment. The results show that in a 50 ml system with 50 μM ATL, CoO2 was selected... x The biomimetic floating bed of / Mo:BiVO4 / Pd-FeOCl-PVDF can adsorb 46% of ATL, compared with CoO4 which does not contain FeOCl. x / Mo:BiVO4 / Pd-PVDF can better fix ATL onto the lower membrane of this biomimetic ecological floating bed, which effectively proves the adsorption and fixation effect of the lower membrane of the double membrane on pollutants in water.

[0052] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0053] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A method for preparing a biomimetic ecological floating bed, characterized in that, Includes the following steps: (1) Preparation of CoO x / Mo:BiVO4 / Pd photocatalyst powder; (2) Preparation of FeOCl adsorption and Fenton-like catalyst powder; (3) The catalyst powders prepared in steps (1) and (2) are added as additives to polymer Poly and DMF to form CoO. x / Mo:BiVO4 / Pd-Poly / DMF and FeOCl-Poly / DMF casting solutions; (4) Based on FeOCl-Poly / DMF casting solution, FeOCl-PVDF film is formed in one step using an automatic coating machine and then dried in situ using a dryer; (5) CoO2 is directly coated onto the FeOCl-PVDF membrane. x / Mo:BiVO4 / Pd-poly / DMF casting solution, automatic coating device for secondary coating to form CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane; (6) After the CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane is left to stand, it is placed in ultrapure water to fully react and complete the phase transformation process, forming a biomimetic ecological floating bed; In step (1), CoO is deposited in stages using photodeposition. x / Mo:BiVO4 and CoO x / Mo:BiVO4 / Pd; Step (1) specifically involves adding NaIO3, Co(NO3)2, and Mo:BiVO4 to a photocatalyst container in a mass ratio of (600±10):(2.25±0.05):(1000±20). N2 is bubbled into the photocatalyst container to create an oxygen-free environment. Under oxygen-free conditions, visible light with a wavelength greater than 420 nm is used to react and fully deposit the Mo:BiVO4 photocatalyst powder. The powder is then washed to remove excess NaIO3 from the solution, and the mixture is filtered and dried to obtain CoO4. x / Mo:BiVO4 photocatalyst powder; Na2PdCl4 and CoO x Mo:BiVO4 photocatalyst powder was added to a photoreaction vessel at a mass ratio of (4±1) mg:(1±0.01) g. An oxygen-free environment was created by purging with N2. Under oxygen-free conditions, visible light was used for complete deposition. The resulting product was then filtered and dried to obtain CoO2. x / Mo:BiVO4 / Pd photocatalyst powder.

2. The method according to claim 1, characterized in that, The specific steps (2) are as follows: 2.0±0.2 g FeCl3·6H2O is placed in a 20 ml or 50 ml covered porcelain crucible, 10±1 ml of anhydrous ethanol is added, and the mixture is evaporated to dryness at 60±5 ℃ and 500±50 rpm. After being placed in a vacuum oven for at least 12 h, the mixture is heated to 220 ℃ in a muffle furnace at a heating rate of 10±1 ℃ / min to fully react and obtain FeOCl adsorption and Fenton-like catalyst powder.

3. The method according to claim 1, characterized in that, The specific steps (3) are as follows: take 850±20 mg Poly and 100±5 mg CoO x / Mo:BiVO4 / Pd powder and 4.26±0.05 ml DMF were reacted completely at 60±5 ℃ and 500±50 rpm to form CoO. x / Mo:BiVO4 / Pd-Poly / DMF casting solution: Take 850±20 mg Poly, 50±1 mg FeOCl powder and 4.26±0.05 ml DMF, and react them fully at 60±5 ℃ and 500±50 rpm to form FeOCl-Poly / DMF casting solution.

4. The method according to claim 1, characterized in that, The specific steps (4) are as follows: the FeOCl-Poly / DMF casting solution is poured evenly onto the starting end of the scraper of the automatic coating machine, the film thickness is set to 200±10μm, and the FeOCl-PVDF film is formed by scraping at a speed of 50±5 mm / s in one go.

5. The method according to claim 1, characterized in that, Step (5) specifically involves: placing CoO x The Mo:BiVO4 / Pd-Poly / DMF casting solution is uniformly poured onto the starting end of the FeOCl-PVDF membrane, and the membrane thickness is set to 500±20μm. The membrane is then scraped a second time at a speed of 50±5mm / s to form a CoOx / Mo:BiVO4 / Pd-FeOCl-PVDF membrane.

6. A biomimetic ecological floating bed, characterized in that, It is prepared by the method according to any one of claims 1-5.

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