Preparation method of corn cob supported flower-like copper sulfide carbonized by floating catalyst

Abstract

The present application relates to a kind of preparation method of floating catalyst carbonized corncob load flower-shaped copper sulfide, through simple chemical precipitation method, in situ synthesis copper sulfide flower-shaped microspheres, and using the adhesion ability and chelating metal ion ability of polydopamine, copper sulfide is deposited on carbonized corncob, and constructs the photocatalytic efficiency high, reusable floating catalyst carbonized corncob load flower-shaped copper sulfide.The present application selects carbonized corncob as floating carrier, can achieve the effect of resource recycling, waste utilization, practices the concept of environment-friendly, sustainable development.And the synthesis method is simple and mild, solve the technical difficulty of traditional hydrothermal method high temperature and high pressure, low cost, high efficiency and economy.The prepared floating catalyst carbonized corncob load flower-shaped copper sulfide can efficiently remove Microcystis aeruginosa under visible light (λ≥420 nm) irradiation for 180 min, and has good stability, and has good application prospect in the treatment of cyanobacterial bloom.

Description

Technical Field

[0001] This invention belongs to the field of photocatalysis technology, specifically relating to a method for preparing flower-shaped copper sulfide supported on corn cobs by a floating catalyst carbonization. Background Technology

[0002] In recent years, eutrophication of water bodies, exacerbated by climate change and human interference, has led to frequent cyanobacterial blooms. Large-scale cyanobacterial blooms reduce water transparency and dissolved oxygen levels, disrupting the balance of aquatic ecosystems. Furthermore, cyanobacterial cells release toxic compounds such as algal toxins, causing aquatic environmental quality deterioration and posing a serious health threat to humans and aquatic organisms. Therefore, developing green and efficient new technologies is of great significance for controlling cyanobacterial blooms, purifying freshwater environments, and achieving sustainable social development.

[0003] Photocatalysis technology has advantages such as energy saving and environmental protection, and is widely used in wastewater treatment. However, powdered photocatalysts have problems such as easy settling, difficulty in recycling, and secondary pollution when treating water pollution. Moreover, under natural conditions, sunlight can only reach a few meters underwater, resulting in low light utilization. Therefore, this paper selects waste corn cobs as a floating carrier to prepare a floating photocatalyst.

[0004] Copper-based chalcogenides have attracted widespread attention as novel semiconductor photocatalysts. Among chalcogenides, Cu is one of the most promising materials, possessing excellent optical, electrical, and structural properties. Most importantly, it has a narrow band gap (less than 2.2 eV), strong light absorption in the near-infrared region, and excellent photothermal conversion performance. Therefore, this study selected CuS, which has a narrow band gap and a wide photoresponse range, and loaded it onto floating waste corn cobs. However, CuS also suffers from drawbacks such as high recombination rate of photogenerated carriers and easy photoreduction, making it difficult to load onto corn cobs. Therefore, we introduced polydopamine to overcome these difficulties. Polydopamine (PDA) is a polymer derived from dopamine (DA), containing a large number of catechol groups and amine functional groups, allowing it to adsorb onto the surface of almost all solid materials. Furthermore, the catechol groups can fix metal ions onto the matrix through chelation, and due to π-π superposition interactions, PDA has the ability to effectively transfer photoinduced electrons and protons. Therefore, this invention employs a simple chemical precipitation method with low energy consumption, using polydopamine as a medium to grow CuS in situ on carbonized corn cobs, thus preparing a floating catalyst for carbonized corn cob-supported flower-shaped copper sulfide.

[0005] Patents CN110282652A and CN113548687A disclose a 3D flower-shaped copper sulfide and its hydrothermal preparation method, and a method for preparing flower-shaped copper sulfide with different petal sizes, respectively. However, these methods all employ high-temperature synthesis, resulting in high energy consumption and complex processes. Furthermore, they do not address the problems of difficult recovery and easy secondary pollution of powdered catalysts. Therefore, developing a simple floating catalyst for carbonizing corn cob-supported flower-shaped copper sulfide is of great significance. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing flower-shaped copper sulfide supported on carbonized corn cobs using a floating catalyst. This invention employs a simple chemical precipitation method, introducing polydopamine and adjusting the raw material ratio to achieve in-situ growth of flower-shaped copper sulfide on carbonized corn cobs. The introduction of polydopamine not only achieves the purpose of depositing copper sulfide on carbonized corn cobs but also regulates the morphology of copper sulfide, accelerates electron transfer and transport, promotes the separation of photogenerated electrons and holes, and improves photocatalytic efficiency.

[0007] The above-mentioned objective of the present invention is achieved through the following technical solution:

[0008] A method for preparing flower-shaped copper sulfide supported on corn cob by a floating catalyst carbonization process includes the following steps:

[0009] (1) Place the corn cob in a tube furnace and calcine it under a nitrogen atmosphere. Then clean it with 15% hydrochloric acid, anhydrous ethanol and deionized water respectively, and dry it to obtain carbonized corn cob for later use.

[0010] (2) Dissolve dopamine hydrochloride and copper salt together in deionized water to obtain solution A. Take the carbonized corn cob obtained in step (1) and place it in solution A. Stir evenly to obtain mixed system 1.

[0011] (3) Dissolve tris(hydroxymethyl)aminomethane hydrochloride in deionized water, add it dropwise to the mixture system 1 described in step (2), adjust the pH value to 8.5, and stir evenly to obtain mixture system 2;

[0012] (4) Dissolve sodium sulfide nonahydrate in deionized water and add it dropwise to the mixture system 2 described in step (3), stir evenly to obtain mixture system 3;

[0013] (5) Filter the mixture system 3 described in step (4) and dry the resulting solid to obtain carbonized corn cob loaded with flower-shaped copper sulfide.

[0014] Preferably, in step (1), the specifications of the corn cob are: 3~8cm in length and 2~5cm in diameter.

[0015] Preferably, in step (1), the calcination heating process is as follows: the temperature is increased to 700-900℃ at a rate of 4-8℃ / min, and held for 1-3 hours.

[0016] Preferably, in step (2), the mass of dopamine hydrochloride is 0.8~1.2g, and the mass concentration of dopamine hydrochloride dissolved in deionized water is 13.3~20mg / mL.

[0017] Preferably, in step (2), the copper salt is copper acetate monohydrate with a mass of 0.39~0.48g, and the mass concentration of the copper acetate monohydrate dissolved in deionized water is 6.5~8.0 mg / mL.

[0018] Preferably, in step (2), the mass of the carbonized corn cob is 1.2~2.4 g, the mass concentration of the carbonized corn cob in deionized water is 20~40 mg / mL, and the stirring time is 1~2 h.

[0019] Preferably, in step (3), the mass of the trihydroxymethylaminomethane hydrochloride is 0.9~1.1g, the mass concentration of the trihydroxymethylaminomethane hydrochloride dissolved in deionized water is 30~36.7mg / mL, and the stirring time is 2~3h.

[0020] Preferably, in step (4), the sodium sulfide nonahydrate has a mass of 0.48~0.5g, the sodium sulfide nonahydrate dissolved in deionized water has a mass concentration of 24~25mg / mL, and the stirring time is 0.5~1h.

[0021] Preferably, in step (5), the drying temperature is 50~70℃ and the drying time is 8~12h.

[0022] This invention also provides an application of floating catalyst carbonized corn cob supported with flower-shaped copper sulfide in the photocatalytic degradation of Microcystis aeruginosa.

[0023] Technical effects of the present invention:

[0024] 1. Compared with existing invention methods, this invention uses a simple chemical precipitation method to synthesize floating catalyst carbonized corn cob supported flower-shaped copper sulfide. Previous invention methods mostly use hydrothermal, solvothermal or oil bath heating methods to synthesize flower-shaped copper sulfide, which are cumbersome, energy-intensive and dangerous. The method of this invention is convenient to operate, simple in steps and low in cost.

[0025] 2. This invention introduces polydopamine by polymerizing dopamine hydrochloride in an alkaline tris(hydroxymethyl)aminomethane hydrochloride solution. Utilizing its strong adhesion and chelating ability to metal ions, it stably loads flower-shaped copper sulfide onto carbonized corn cobs. This not only solves the problem of easy agglomeration and precipitation of copper sulfide powder, but also, the π-π conjugated structure inside polydopamine has the ability to transfer electrons, which can accelerate the transfer of photogenerated electrons and improve photocatalytic efficiency.

[0026] 3. The floating catalyst carbonized corn cob supported flower-shaped copper sulfide provided by this invention can be applied to the field of photocatalytic algae removal. Due to the phototactic nature of algae, which aggregate and grow on the water surface, the floating catalyst carbonized corn cob supported flower-shaped copper sulfide can reach the algae / water interface to the maximum extent without stirring, improving the utilization rate of light and active free radicals in the photocatalytic reaction, thereby achieving a better photocatalytic algae removal effect. After 180 minutes of visible light irradiation, the floating catalyst carbonized corn cob supported flower-shaped copper sulfide can reduce OD... 680 The algae degradation efficiency reached 95% at a concentration of approximately 0.6%.

[0027] 4. The floating catalyst carbonized corn cob loaded with flower-shaped copper sulfide provided by the present invention controls the amount of each preparation raw material (such as dopamine hydrochloride, copper salt, sodium sulfide nonahydrate) added, so that the copper sulfide loaded on the carbonized corn cob is in the shape of micron-sized flower balls, and the loading is uniform and not easy to fall off, which ultimately improves its photocatalytic algae removal performance.

[0028] 5. The floating carrier selected in this invention is corn cob, a type of solid waste. This choice of carrier takes into account the concepts of environmental friendliness and sustainable development. Traditional incineration methods for treating agricultural waste are inherently hazardous. Therefore, the inventors selected corn cob as a carrier for the photocatalyst to achieve resource recovery, waste utilization, and cost reduction. Attached Figure Description

[0029] Figure 1 This is an X-ray diffraction pattern of flower-shaped copper sulfide supported on corn cob by a floating catalyst provided by the present invention.

[0030] Figure 2 The X-ray photoelectron spectroscopy (XPS) spectra of corn cob supported on flower-shaped copper sulfide by the floating catalyst provided by this invention are shown in Figure (a) for its full spectrum, b for the Cu 2p spectrum, and c for the S 2p spectrum).

[0031] Figure 3 This is the UV-Vis diffuse reflectance spectrum of corn cob supported on flower-shaped copper sulfide by the floating catalyst provided by this invention;

[0032] Figure 4 This is a scanning electron microscope image of the floating catalyst carbonized corn cob supported with flower-like copper sulfide prepared in Example 1 of this invention;

[0033] Figure 5 This is a scanning electron microscope image of the floating catalyst carbonized corn cob supported on flower-shaped copper sulfide prepared in Comparative Example 1 of the present invention.

[0034] Figure 6 This is a scanning electron microscope image of the floating catalyst carbonized corn cob supported with flower-shaped copper sulfide prepared in Comparative Example 2 of this invention.

[0035] Figure 7 This is a scanning electron microscope image of the floating catalyst carbonized corn cob supported on flower-shaped copper sulfide prepared in Comparative Example 3 of the present invention.

[0036] Figure 8 This is a scanning electron microscope image of the floating catalyst carbonized corn cob supported with flower-like copper sulfide prepared in Comparative Example 4 of this invention.

[0037] Figure 9 This is a scanning electron microscope image of the floating catalyst carbonized corn cob supported on flower-shaped copper sulfide prepared in Comparative Example 5 of this invention.

[0038] Figure 10 This is a graph showing the removal efficiency of Microcystis aeruginosa cells by floating catalyst carbonized corn cob-supported flower-shaped copper sulfide provided by the present invention under visible light (λ≥420nm) irradiation. Detailed Implementation

[0039] To further understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings and examples. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0040] For experimental methods in the following examples where specific conditions are not specified, follow conventional methods and conditions, or select according to the product instructions. Example 1

[0041] A method for preparing floating catalyst-carbonized corn cob supported flower-shaped copper sulfide is as follows:

[0042] (1) Place a corn cob with a length of 5cm and a diameter of 2.5cm in a tube furnace and calcine it under a nitrogen atmosphere. The temperature is raised to 800℃ at a rate of 5℃ / min and kept at that temperature for 2h. Then, it is cleaned with 15% hydrochloric acid, ethanol and deionized water respectively, and dried to obtain carbonized corn cob for later use.

[0043] (2) Dissolve 1g of dopamine hydrochloride and 0.3992g of copper salt in 60mL of deionized water to obtain solution A. Take 1.8g of carbonized corn cob obtained in step (1) and place it in solution A. Stir for 1h to obtain mixed system 1.

[0044] (3) Dissolve 1g of tris(hydroxymethyl)aminomethane hydrochloride in 30mL of deionized water, add it dropwise to the mixture system 1 described in step (2), adjust the pH to 8.5, and stir for 3h to obtain mixture system 2;

[0045] (4) Dissolve 0.48g sodium sulfide nonahydrate in 20mL of deionized water, add it dropwise to the mixture system 2 described in step (3), stir for 30min to obtain mixture system 3;

[0046] (5) Filter the mixture system 3 described in step (4), place the obtained solid in an oven and dry it at 60°C for 12 hours to obtain carbonized corn cob loaded with flower-shaped copper sulfide (CuS / PDA / CC-1). Example 2

[0047] A method for preparing flower-shaped copper sulfide supported on corn cob by a floating catalyst carbonization process includes the following steps:

[0048] (1) Place the corn cob (3cm long and 2cm in diameter) in a tube furnace and calcine it under a nitrogen atmosphere. The temperature is raised to 700℃ at a rate of 4℃ / min and kept at that temperature for 3h. Then, clean it with 15% hydrochloric acid, anhydrous ethanol and deionized water respectively, and dry it to obtain carbonized corn cob for later use.

[0049] (2) Dissolve 0.8g of dopamine hydrochloride and 0.42g of copper acetate monohydrate in 60mL of deionized water to obtain solution A. Take 1.2g of carbonized corn cob obtained in step (1) and place it in solution A. Stir for 1.5 h to obtain mixed system 1.

[0050] (3) Dissolve 0.9g of tris(hydroxymethyl)aminomethane hydrochloride in 30mL of deionized water, add it dropwise to the mixture system 1 described in step (2), adjust the pH value to 8.5, stir for 2.5h to obtain mixture system 2;

[0051] (4) Dissolve 0.48g sodium sulfide nonahydrate in 20mL of deionized water, add it dropwise to the mixture system 2 described in step (3), stir for 0.5 h to obtain mixture system 3;

[0052] (5) Filter the mixture system 3 described in step (4), and dry the resulting solid at 50°C for 10 hours to obtain carbonized corn cob loaded with flower-shaped copper sulfide. Example 3

[0053] A method for preparing flower-shaped copper sulfide supported on corn cob by a floating catalyst carbonization process includes the following steps:

[0054] (1) Place the corn cob (8cm long and 5cm in diameter) in a tube furnace and calcine it under a nitrogen atmosphere. The temperature is raised to 900℃ at a rate of 8℃ / min and kept at that temperature for 1h. Then, clean it with 15% hydrochloric acid, anhydrous ethanol and deionized water respectively, and dry it to obtain carbonized corn cob for later use.

[0055] (2) Dissolve 1.2g of dopamine hydrochloride and 0.48g of copper acetate monohydrate in 60mL of deionized water to obtain solution A. Take 2.4g of carbonized corn cob obtained in step (1) and place it in solution A. Stir for 2 h to obtain mixed system 1.

[0056] (3) Dissolve 1.1g of tris(hydroxymethyl)aminomethane hydrochloride in 30mL of deionized water, add it dropwise to the mixture system 1 described in step (2), adjust the pH value to 8.5, stir for 2h to obtain mixture system 2;

[0057] (4) Dissolve 0.5g sodium sulfide nonahydrate in 20mL of deionized water, add it dropwise to the mixture system 2 described in step (3), stir for 1 h to obtain mixture system 3;

[0058] (5) Filter the mixture system 3 described in step (4), and dry the resulting solid at 70°C for 8 hours to obtain carbonized corn cob loaded with flower-shaped copper sulfide.

[0059] Comparative Example 1

[0060] The difference between this comparative example and Example 1 is that the mass of dopamine hydrochloride in step (2) is 0.5g, and the final product is named CuS / PDA / CC-0.5.

[0061] Comparative Example 2

[0062] The difference between this comparative example and Example 1 is that the mass of dopamine hydrochloride in step (2) is 0g, and the final product is named CuS / PDA / CC-0.

[0063] Comparative Example 3

[0064] The difference between this comparative example and Example 1 is that the mass of dopamine hydrochloride in step (2) is 1.5g, and the final product is named CuS / PDA / CC-1.5.

[0065] Comparative Example 4

[0066] The difference between this comparative example and Example 1 is that the mass of copper acetate monohydrate in step (2) is 0.3g, and the mass of sodium sulfide nonahydrate in step (4) is 0.4g. The final product is named 0.3-CuS / PDA / CC.

[0067] Comparative Example 5

[0068] The difference between this comparative example and Example 1 is that the mass of copper acetate monohydrate in step (2) is 0.6g, the mass of sodium sulfide nonahydrate in step (4) is 0.6g, and the final product is named 0.6-CuS / PDA / CC.

[0069] The characteristics of the floating catalyst for carbonizing corn cob-supported flower-like copper sulfide prepared in this invention were further characterized by X-ray diffraction patterns, X-ray photoelectron spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, and scanning electron microscopy. Figures 1-9 As shown, where Figures 1-4 The characterization refers to the floating catalyst carbonization of corn cob-supported flower-shaped copper sulfide prepared in Example 1. Figures 5-9 Scanning electron microscopy (SEM) images of floating catalysts used in Comparative Examples 1-5 to carbonize corn cob-supported flower-shaped copper sulfide.

[0070] from Figure 1 The X-ray diffraction pattern shows that the diffraction peaks of flower-shaped copper sulfide supported on corn cob by the floating catalyst correspond to the (102), (103), and (110) crystal planes in the copper sulfide standard card. This indicates the successful synthesis of flower-shaped copper sulfide supported on corn cob by the floating catalyst.

[0071] from Figure 2 The X-ray photoelectron spectroscopy (XPS) spectrum shows that CuS / PDA / CC-1 mainly contains five elements: C, N, O, Cu, and S. C, N, and O originate from the polymer PDA, while Cu and S come from CuS. The high-resolution XPS spectrum of the S 2p orbital exhibits strong characteristic peaks at 161.83 eV and 162.82 eV, which is attributed to the S 2p orbital of divalent sulfur ions. 1 / 2 and S 2p 3 / 2 The binding energies at 168.36 eV and 169.45 eV of the orbitals belong to SO bonds formed by oxidation, such as in sulfate compounds. The characteristic peaks at 932.36 eV and 952.19 eV in the high-resolution XPS spectrum of Cu2p are attributed to Cu2p orbitals. 3 / 2 and Cu 2p 1 / 2 All belong to Cu 2+ .

[0072] from Figure 3 The ultraviolet-visible diffuse reflectance spectrum shows that the floating catalyst carbonized corn cob supported flower-shaped copper sulfide has a strong absorption capacity in the visible and even near-infrared regions. This is because CuS has a very small band gap and PDA is also a material with good photothermal properties. Therefore, the material has a good photoresponse in the entire wavelength range.

[0073] from Figure 4Electron scanning microscopy revealed that the copper sulfide prepared according to Example 1 was in the form of micron-sized flower-shaped microspheres, each composed of stacked nanosheets, and the copper sulfide was uniformly loaded on the corn stick carrier and was not easily detached.

[0074] from Figure 5 The scanning electron microscope showed that although the copper sulfide prepared according to Comparative Example 1 was loaded on the carbonized corn cob, it did not form a flower-like shape.

[0075] from Figure 6 As can be seen from the electron scanning microscope, the copper sulfide prepared according to Comparative Example 2 did not successfully load onto the surface of the carbonized corn cob because polydopamine was not introduced.

[0076] from Figure 7 As can be seen from the scanning electron microscope, although the copper sulfide prepared according to Comparative Example 3 retains a small amount of microsphere-like structure, the PDA coverage on the surface is relatively thick, and most of the morphology is no longer complete.

[0077] from Figure 8 As can be seen from the electron scanning microscope, the copper sulfide prepared according to Comparative Example 4 did not form microspheres.

[0078] from Figure 9 Electron scanning microscopy revealed that the copper sulfide prepared according to Comparative Example 5 did not form microspheres.

[0079] Application Example 1

[0080] The inventors also verified the algae-reducing effect of the floating catalyst carbonized corn cob loaded with flower-shaped copper sulfide provided by this invention through the following experiments: The photocatalytic algae removal process was carried out in a 200mL jacketed beaker reactor, using a 300W xenon lamp as a simulated sunlight source, with ultraviolet light with λ<420 nm filtered out using a filter. The algae removal was based on a typical algal density (OD) in eutrophic water. 680 ≈0.6) was used as the initial algal density. For each experiment, 100 mL of algal solution was placed in the reactor. The reaction was carried out in the dark for 30 min, followed by a photocatalytic reaction for 3 h. 3 mL of algal solution was collected every 30 min. The photocatalytic algae removal performance was evaluated by the change in chlorophyll a content. Figure 10 As shown.

[0081] from Figure 10 The degradation diagrams show that among the floating catalysts used to carbonize corn cob-supported flower-shaped copper sulfide prepared according to Examples 1, 1, 2, 3, 4, and 5, the material prepared in Example 1 exhibits the best degradation performance, reaching a degradation rate of 95% in 180 minutes.

[0082] The above description only illustrates the preferred embodiments of the present invention and should not be construed as limiting the scope of the claims. The present invention is not limited to the above embodiments, and variations in its specific structure are permitted. All modifications made within the scope of the independent claims of this invention are also within the scope of protection of this invention.

Claims

1. A method for preparing floating catalyst carbonized corn cob-supported flower-like copper sulfide for photocatalytic degradation of Microcystis aeruginosa, characterized in that: The method includes the following steps: (1) Place the corn cob in a tube furnace and calcine it under a nitrogen atmosphere. Then clean it with 15% hydrochloric acid, anhydrous ethanol and deionized water respectively, and dry it to obtain carbonized corn cob for later use. (2) Dissolve dopamine hydrochloride and copper salt together in deionized water to obtain solution A. Take the carbonized corn cob obtained in step (1) and place it in solution A. Stir evenly to obtain mixed system 1. (3) Dissolve tris(hydroxymethyl)aminomethane hydrochloride in deionized water, add it dropwise to the mixture system 1 described in step (2), adjust the pH value to 8.5, and stir evenly to obtain mixture system 2; (4) Dissolve sodium sulfide nonahydrate in deionized water and add it dropwise to the mixture system 2 described in step (3), stir evenly to obtain mixture system 3; (5) Filter the mixture system 3 described in step (4) and dry the resulting solid to obtain carbonized corn cob loaded with flower-shaped copper sulfide; In step (2), the mass of the carbonized corn cob is 1.2~2.4 g; The mass of the dopamine hydrochloride is 0.8~1.2g; The copper salt is copper acetate monohydrate, with a mass of 0.39~0.48g; In step (4), the mass of the sodium sulfide nonahydrate is 0.48~0.5g.

2. The method for preparing floating catalyst carbonized corn cob supported flower-shaped copper sulfide as described in claim 1, characterized in that: In step (1), the specifications of the corn cob are: 3~8cm in length and 2~5cm in diameter.

3. The method for preparing floating catalyst carbonized corn cob supported flower-shaped copper sulfide as described in claim 1, characterized in that: In step (1), the calcination heating process is as follows: the temperature is increased to 700-900℃ at a rate of 4-8℃ / min, and held for 1-3 hours.

4. The method for preparing floating catalyst carbonized corn cob supported flower-shaped copper sulfide as described in claim 1, characterized in that: In step (2), the mass concentration of dopamine hydrochloride dissolved in deionized water is 13.3~20 mg / mL.

5. The method for preparing floating catalyst carbonized corn cob supported flower-shaped copper sulfide as described in claim 1, characterized in that: In step (2), the mass concentration of the copper acetate monohydrate dissolved in deionized water is 6.5~8.0 mg / mL.

6. The method for preparing floating catalyst carbonized corn cob supported flower-shaped copper sulfide as described in claim 1, characterized in that: In step (2), the carbonized corn cob is placed in deionized water with a mass concentration of 20~40 mg / mL and a stirring time of 1~2 h.

7. The method for preparing floating catalyst carbonized corn cob supported flower-shaped copper sulfide as described in claim 1, characterized in that: In step (3), the mass of the trihydroxymethylaminomethane hydrochloride is 0.9~1.1g, the mass concentration of the trihydroxymethylaminomethane hydrochloride dissolved in deionized water is 30~36.7mg / mL, and the stirring time is 2~3h.

8. The method for preparing floating catalyst carbonized corn cob supported flower-shaped copper sulfide as described in claim 1, characterized in that: In step (4), the mass concentration of sodium sulfide nonahydrate dissolved in deionized water is 24~25 mg / mL, and the stirring time is 0.5~1 h.

9. The method for preparing floating catalyst carbonized corn cob supported flower-shaped copper sulfide as described in claim 1, characterized in that: In step (5), the drying temperature is 50~70℃ and the drying time is 8~12h.

10. The application of a floating catalyst carbonized corn cob supported on flower-shaped copper sulfide, prepared by any one of claims 1 to 9, in the photocatalytic degradation of Microcystis aeruginosa.

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