A removal method based on magnetic cellulose electro-coagulation system and algae

Abstract

The application discloses a kind of based on magnetic cellulose electric coagulation system, comprising the following steps: with reticular electrode PbO2-Ti and Ti respectively as anode and cathode, concentration is 0.02~0.08g / L magnetic cellulose is added into electrolyte, constructs magnetic cellulose electric coagulation system;The application also discloses a kind of removal method of algae, and magnetic cellulose material has better conductivity and higher charge transfer rate, has greater charge storage capacity and higher specific capacitance, can be used as three-dimensional particle electrode strengthening system polarization in magnetic cellulose electric coagulation system, significantly reduce the energy consumption of electric coagulation system while also improve the efficiency of algae removal.

Description

Technical Field

[0001] This invention belongs to the field of wastewater purification and treatment in environmental protection, and specifically relates to a method for removing algae based on a magnetic cellulose electrocoagulation system. Background Technology

[0002] Microcystis aeruginosa is a highly toxic algae that can have severe ecological consequences when it proliferates rapidly. Its growth reduces water transparency and negatively impacts photosynthesis in aquatic organisms. Furthermore, when Microcystis aeruginosa proliferates or decomposes in large quantities, it releases pollutants that pose a threat to human and animal health. Finally, an excessive presence of Microcystis aeruginosa can affect the odor and taste of water, leading to water quality deterioration.

[0003] Common methods for treating Microcystis aeruginosa include physical control, chemical control, and biological control. Chemical control is a frequently used method, involving the use of chemicals such as copper sulfate and chlorides to inhibit and eliminate algae growth in water. While widely used, this method has the drawback of potentially causing secondary pollution from residual chemicals, which can have harmful effects on humans and other organisms. To overcome the limitations of chemical algae removal, electrochemical methods have emerged as alternatives in recent years. This technology utilizes electrochemical reactions to generate strong oxidants, which not only eliminate Microcystis aeruginosa but also promote the partial decomposition of algal metabolites. Electrocoagulation is a method for treating pollutants in water based on electrochemical principles. It utilizes the potential and concentration differences between electrodes to cause pollutant molecules to aggregate onto the electrodes, where they are then agglomerated or oxidized into harmless substances. Compared to traditional chemical and physical treatment methods, electrocoagulation offers advantages such as high efficiency, environmental friendliness, wide applicability, and simple operation, showing significant effectiveness in degrading pollutants in water. However, current electrochemical algae removal technologies consume excessive energy, necessitating further research into the mechanisms of algae removal and how to reduce energy consumption. Summary of the Invention

[0004] In order to overcome the shortcomings of the existing technology, the purpose of this invention is to provide an electrocoagulation system based on magnetic cellulose to solve the problem of excessive energy consumption in electrochemical algae removal.

[0005] The present invention also provides a method for removing algae.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] An electrocoagulation system based on magnetic cellulose includes the following steps:

[0008] A magnetic cellulose electrocoagulation system was constructed by adding magnetic cellulose with a concentration of 0.02–0.08 g / L to an electrolyte, using mesh electrodes PbO2-Ti and Ti as the anode and cathode, respectively.

[0009] Preferably, the mesh electrodes PbO2-Ti and Ti are placed vertically in the electrolyte, with an immersion area of ​​3 / 4.

[0010] More preferably, the dimensions of the mesh electrode PbO2-Ti and the Ti electrode sheet are 7.0cm*2.5cm*0.1cm.

[0011] More preferably, the distance between the anode and cathode is 4.0 cm.

[0012] Preferably, the pH value of the electrolyte is 3 to 11.

[0013] Preferably, the method for preparing the magnetic fiber includes the following steps:

[0014] Magnetic cellulose was prepared by mixing cellulose, FeCl2-4H2O and FeCl3-6H2O, dissolving them in deionized water, slowly adding ammonia, and finally washing and drying.

[0015] More preferably, the washing process involves washing the magnetic cellulose until it becomes neutral.

[0016] More preferably, Fe 2+ and Fe 3+ The molar ratio is 1:2 to 3, and the volume ratio of the deionized water to the ammonia water is 120:15 to 20.

[0017] Preferably, the cellulose is extracted from Napier grass, and the extraction method is the nitric acid ethanol method.

[0018] A method for removing algae, based on the electrocoagulation system, wherein the electrocoagulation system is electrolyzed for 1 to 45 minutes; wherein the electrolyte is a mixture of algae to be removed and a supporting electrolyte.

[0019] Preferably, the supporting electrolyte includes one of anhydrous sodium sulfate, potassium nitrate, or a mixed solution of potassium ferricyanide and potassium chloride.

[0020] More preferably, the supporting electrolyte is anhydrous sodium sulfate.

[0021] Preferably, the current density during the electrolysis process is 7–35 mA / cm². 2 .

[0022] Preferably, the algae to be removed is Microcystis aeruginosa.

[0023] More preferably, the concentration of the *Microcystis aeruginosa* is 2–6 x 10⁻⁶. 6 cells / ml.

[0024] Preferably, the volume of the electrolyte is 150-500 mL.

[0025] The present invention has the following advantages and beneficial effects compared with the prior art:

[0026] (1) Magnetic cellulose materials have good electrical conductivity and higher charge transfer rate, with greater charge storage capacity and higher specific capacitance. In the electrocoagulation system, they can be used as three-dimensional particle electrodes to enhance the polarization of the system, significantly reducing the energy consumption of the electrocoagulation system while improving the efficiency of algae removal.

[0027] (2) This invention uses magnetic cellulose material as a carrier for an electrocoagulation system, constructing a magnetic cellulose electrocoagulation system that degrades Microcystis algae through the synergistic effect of free radicals and non-free radicals. Magnetic cellulose can generate hydroxyl radicals (·OH) and singlet oxygen (·OH) under the action of the electrochemical system. 1 O2), which can induce apoptosis in algal cells in the system, among which 1 O2 is the main reactive oxygen species and plays a major role in electrocoagulation algae removal systems.

[0028] (3) This invention utilizes waste resources, using Napier grass as a raw material for cellulose preparation. By imparting magnetism to it, it achieves the purpose of green recycling. At the same time, it enhances the conductivity of the system and greatly saves energy consumption. The energy used is electrical energy, which is clean and has no secondary pollution. In different control systems, the electrolytic magnetic fiber system achieves the best removal effect on algal cells and can completely remove Microcystis aeruginosa within 45 minutes. Attached Figure Description

[0029] Figure 1 The images show SEM images of magnetic cellulose before and after the reaction.

[0030] Figure 2 The images show SEM images of algal cells in different systems in Example 1.

[0031] Figure 3 The image shows XPS images of the magnetic fibers before and after the reaction.

[0032] Figure 4 The image shows the removal effect of different systems on Microcystis aeruginosa in Example 1.

[0033] Figure 5 The image shows the removal effect of chlorophyll a in Microcystis aeruginosa under different systems in Example 1.

[0034] Figure 6The graph shows the removal efficiency of different concentrations of magnetic cellulose in Example 2 for removing Microcystis aeruginosa.

[0035] Figure 7 The graph shows the removal efficiency of Microcystis aeruginosa at different current densities in Example 3.

[0036] Figure 8 The graph shows the removal efficiency of Microcystis aeruginosa under different pH conditions in Example 4.

[0037] Figure 9 This is a staining image of algal cells under a confocal microscope.

[0038] Figure 10 This is a three-dimensional fluorescence spectrum of extracellular organic matter.

[0039] Figure 11 This is a characterization diagram of magnetic cellulose.

[0040] Figure 12 This is a pathway diagram of Microcystis aeruginosa degrading algal cells in a magnetic cellulose electrocoagulation system. Detailed Implementation

[0041] The invention's objective will be further described in detail below with reference to the accompanying drawings and specific embodiments. The embodiments cannot be described in detail here, but the implementation of the invention is not limited to the following embodiments.

[0042] Example 1

[0043] Pretreatment of Napier grass and extraction of its cellulose:

[0044] The Napier grass samples were collected from an experimental base. First, the collected Napier grass was thoroughly washed and then dried completely at 80℃. Subsequently, the dried sample was pulverized and sieved to a mesh size of 0.15 mm. Cellulose was extracted from the sample using the nitric acid-ethanol method to remove lignin and hemicellulose from the extracted cellulose.

[0045] Preparation process of magnetic cellulose materials:

[0046] Weigh out 0.6g of extracted cellulose, 0.52g of FeCl₂-4H₂O, and 1.77g of FeCl₃-6H₂O, mix them to form a mixture, Fe 2+ / Fe 3+ The molar ratio is 1:2. Add 120 ml of deionized water to dissolve the mixture, then slowly add 15 ml of ammonia water. Stir for 30 minutes under argon protection, ensuring the entire magnetization process is carried out to prevent the influence of air. Finally, wash the magnetic cellulose to achieve a neutral pH, dry it, and grind it into powder for subsequent use.

[0047] Comparison of different systems for removing Microcystis aeruginosa

[0048] Pure electrolytic degradation system: Mesh PbO2-Ti and Ti electrode sheets were used as the anode and cathode, respectively, with electrode plate dimensions of 7.0cm*2.5cm*0.1cm. The distance between the main electrodes was maintained at 4.0cm. The electrodes were vertically immersed in a beaker containing 250ml of a mixed aqueous solution of *Microcystis aeruginosa* at a certain concentration and 4.0g / L Na2SO4 electrolyte. Electrocoagulation and algae removal experiments were conducted at 700rpm for 45min under an electrolytic current of 0.45A and initial pH. The algae removal results are as follows: Figure 4 and Figure 5 As shown.

[0049] Magnetic cellulose system: Magnetic cellulose was added to a beaker containing a certain concentration of Microcystis aeruginosa and a 4.0 g / L Na₂SO₄ electrolyte solution to achieve a magnetic cellulose concentration of 0.04 g / L. The mixture was stirred at 700 rpm for 45 min to conduct a degradation experiment. Algae removal results are as follows: Figure 4 and Figure 5 As shown.

[0050] Electrolysis and cellulose systems: Mesh PbO2-Ti and Ti electrode sheets were used as the anode and cathode of the main electrodes, respectively. The electrode sheet dimensions were 7.0cm*2.5cm*0.1cm, and the distance between the main electrodes was maintained at 4.0cm. The electrodes were vertically immersed in a 250ml beaker containing a certain concentration of *Microcystis aeruginosa* and a 4.0g / L Na2SO4 electrolyte solution. The cellulose concentration was 0.04g / L. Electrocoagulation and algae removal experiments were conducted at 700rpm for 45min with an applied current of 0.45A and at the initial pH. The algae removal results are as follows: Figure 4 and Figure 5 As shown.

[0051] Electrolysis and Fe3O4 system: Mesh PbO2-Ti and Ti electrode sheets were used as the anode and cathode of the main electrodes, respectively. The electrode sheet dimensions were 7.0cm*2.5cm*0.1cm, and the distance between the main electrodes was maintained at 4.0cm. The electrodes were vertically immersed in a 250ml beaker containing a certain concentration of *Microcystis aeruginosa* and a 4.0g / L Na2SO4 electrolyte solution. The cellulose concentration was 0.04g / L. Electrocoagulation and algae removal experiments were conducted at 700rpm for 45min with an applied current of 0.45A and at the initial pH. The algae removal results are as follows: Figure 4 and Figure 5 As shown.

[0052] Electrolytic and magnetic cellulose systems: Mesh PbO2-Ti and Ti electrode sheets were used as the anode and cathode, respectively, with electrode plate dimensions of 7.0cm*2.5cm*0.1cm. The distance between the main electrodes was maintained at 4.0cm. The electrodes were vertically immersed in a beaker containing 250ml of a mixed aqueous solution of *Microcystis aeruginosa* and 4.0g / L Na2SO4 electrolyte. Magnetic cellulose was added to achieve a concentration of 0.04g / L. Electrocoagulation and algae removal experiments were conducted at 700rpm for 45min with an applied current of 0.45A and at the initial pH. The algae removal results are as follows: Figure 4 and Figure 5 As shown.

[0053] Example 2

[0054] The pretreatment of Napier grass, its cellulose extraction process, and the preparation process of magnetic cellulose materials are the same as in Example 1.

[0055] Magnetic cellulose solutions with concentrations of 0.02 g / L, 0.04 g / L, 0.06 g / L, and 0.08 g / L were prepared respectively. The prepared magnetic cellulose electrocoagulation material was then added to 250 ml of a mixed aqueous solution of *Microcystis aeruginosa* electrolyte (3.7 x 10⁻⁶ g / L). 6 The algal cell density (cells / ml) was determined by mixing algae in 4.0 g / L Na2SO4, and the mixture was stirred at 700 rpm on a multi-stage digital display magnetic stirrer with a constant current of 0.45 A. Samples were taken at 5, 10, 15, 30, and 45 minutes after the start of the experiment; the test results are shown below. Figure 6 As shown.

[0056] Example 3

[0057] The pretreatment of Napier grass, its cellulose extraction process, and the preparation process of magnetic cellulose materials are the same as in Example 1.

[0058] The magnetic cellulose electrocoagulation material prepared above, with a concentration of 0.04 g / L, was added to 250 ml of the above-mentioned mixed aqueous solution of Microcystis aeruginosa electrolyte (3.7*10). 6 The algae were added to a solution containing 4.0 g / L Na₂SO₄ at a cell density of 100 cells / ml, and stirred at 700 rpm on a multi-stage digital display magnetic stirrer. Constant currents of 0.15 A, 0.30 A, 0.45 A, and 0.6 A were applied at these currents. Samples were taken at 5, 10, 15, 30, and 45 minutes after the start of the experiment. The test results are as follows: Figure 7 As shown.

[0059] Example 4

[0060] The pretreatment of Napier grass, its cellulose extraction process, and the preparation process of magnetic cellulose materials are the same as in Example 1.

[0061] The magnetic cellulose electrocoagulation material prepared above with a concentration of 0.04 g / L was added to 250 ml of the above-mentioned mixed aqueous solution of Microcystis aeruginosa electrolyte (3.7*10). 6 Algal cell density (cells / ml) and 4.0 g / L Na2SO4 were added and stirred at 700 rpm on a multi-stage digital display magnetic stirrer. A 0.45 A current was applied, and the pH was adjusted to 3, 5, 7, 9, and 11. Samples were taken and tested at 5 min, 10 min, 15 min, 30 min, and 45 min after the start of the experiment. The test results are as follows: Figure 8 As shown.

[0062] Figure 1 Here are SEM images of magnetic cellulose before and after the reaction, from... Figure 1 As shown in a, 1b, and 1c, before the electrochemical reaction, the surface of the magnetic cellulose has a large number of relatively uniform Fe3O4 nanoparticles. Figure 1 As shown in d, 1b, and 1c, the surface of magnetic cellulose undergoes oxidation during operation in an electrochemical system, leading to changes in its pore structure. This change results in a surface transition from smooth to rough, providing a larger contact area and more adhesion sites, thereby increasing the rate of electrochemical reactions. Furthermore, the rough surface structure accommodates more active sites and a more complex interfacial arrangement, thus improving mass transfer efficiency. When magnetic cellulose is used as a three-dimensional particulate electrode in an electrochemical algae removal system, these modifications enhance its stability and durability.

[0063] Figure 2 These are SEM images of algal cells in different systems from Example 1. Figure 2 As can be seen from a, the control group contained a large number of structurally intact algal cells, all of which exhibited high activity. For example... Figure 2 As shown in Figure b, when magnetic cellulose was used as the particulate electrode in the electrochemical system, a large number of algal cells were observed to be removed. The remaining algal cells showed wrinkled surfaces, indicating that their activity and overall cellular structure were damaged, or even completely lost. Therefore, scanning electron microscopy (SEM) analysis effectively revealed the removal effect of the three-dimensional electrochemical magnetic cellulose system on Microcystis aeruginosa. Figure 2 As shown in Figure c, a significant decrease in cell number was observed when an electric current was applied to the algal cells. This indicates that electrical stimulation damages the algal cell structure, thereby effectively achieving algae removal. The surviving algal cells had relatively smooth surfaces and showed signs of apoptosis.

[0064] Figure 3 These are XPS images of the magnetic fibers before and after the reaction, from... Figure 3It can be seen that Fe, O and C coexist after cellulose modification, and the elemental changes after the reaction are very small. Figure 3 As shown in Figure b, the peaks at 710.0 and 724.6 eV correspond to Fe(III)2p 3 / 2 and Fe(III)2p1 / 2, respectively, while the peaks at 708.5 eV and 722.5 eV correspond to Fe(II)2p 3 / 2 and Fe(II)2p1 / 2, respectively. These results are consistent with the Fe 2p XPS spectra of Fe3O4 reported elsewhere, indicating that Fe3O4 was successfully loaded after cellulose modification. Furthermore, Fe... 3+ / Fe 2+ The area ratio is approximately 0.5, which is consistent with the stoichiometry of Fe3O4 reported in the literature, irrefutably demonstrating the stability and near-complete retention of the supported material.

[0065] Figure 4 The graphs show the removal effects of different systems on Microcystis aeruginosa in Example 1. Figure 4 It was found that adding magnetic cellulose alone had a weak ability to remove algal cell density; the removal rate within 45 minutes was less than 10%. In contrast, electrolysis alone could remove some algal cells, with a removal rate of 45.2% after 45 minutes. Meanwhile, within the same time frame, the removal rates of cellulose and Fe3O4 particle electrodes were 44.3% and 66.1%, respectively, with the electrochemical system incorporating magnetic cellulose showing the best performance. The three-dimensional particle electrode using magnetic cellulose was able to completely remove algal cells within 45 minutes, highlighting the significantly improved removal efficiency of the electrochemical system for Microcystis aeruginosa.

[0066] Figure 5 The figures show the removal efficiency of chlorophyll a from Microcystis aeruginosa under different systems. When magnetic cellulose was used alone, the removal rate of chlorophyll a within 5 minutes was 14.2%, while the removal rates of electrolysis and electrolysis with magnetic fibers were 36.1% and 71.9%, respectively. The granular electrode system filled with magnetic cellulose showed the highest removal rate of chlorophyll a within 5 minutes, demonstrating a significant effect. Chlorophyll a was observed to be completely removed within 30 minutes, indicating that magnetic cellulose as a granular electrode is more effective than cellulose and Fe3O4. The results show that the three-dimensional electrochemical magnetic cellulose system extensively disrupts the algal cell membrane, causing chlorophyll a to leak from the cells into the solution, where it is subsequently decomposed through electrochemical oxidation. After electrolysis, some inactivated algal cells remained relatively intact, but the chlorophyll a within them had leaked into the solution through the damaged cell membrane and cell wall. Therefore, the removal rate of chlorophyll a was higher than that of algal cell density.

[0067] Figure 6 The graph shows the removal efficiency of different concentrations of magnetic cellulose for removing Microcystis aeruginosa in Example 2. Figure 6As shown, the system achieved the highest removal rate of *Microcystis aeruginosa* when the concentration of magnetic cellulose as the particulate electrode was 0.04 g / L. With increasing particulate electrode concentration, the three-dimensional electrochemical reaction region and active sites expanded, thereby improving mass transfer efficiency. However, when the amount of magnetic cellulose was excessive, the continuous increase in particulate electrode concentration eventually weakened the system's ability to remove algal cells. The electrode may be overloaded, resulting in side effects and thus affecting the removal efficiency of the three-dimensional electrochemical magnetic cellulose system for algal cells. Studies on chlorophyll a removal also showed that the removal effect was optimal when the magnetic cellulose concentration was 0.04 g / L.

[0068] Figure 7 The graph shows the removal efficiency of Microcystis aeruginosa at different current densities in Example 3. The results are as follows: Figure 7 As shown, the three-dimensional electrochemical magnetic cellulose system is significantly affected when the current density is too low. In this case, the removal rate of algal cells is approximately 10% within 45 minutes. Insufficient current density hinders the stimulating effect of the electrochemical system on algal cells, thus failing to fully utilize the synergistic effect between the particulate electrode and the electrode plate. With increasing current density, the removal efficiency of algal cells gradually improves. This improvement is mainly due to the increased driving force for repolarization of the particulate electrode as the current intensity increases. At a current density of 21 mA / cm², the removal efficiency is significantly improved. 2 At a specific current density, the removal effect is optimal, with a removal rate as high as 45.2% within 5 minutes. However, as the current density increases, the removal capacity of the algal cells decreases. This decrease may be due to the potentially adverse effects of excessively high current density on the algal cells. Only 21 mA / cm²... 2 and 35mA / cm 2 A current density of 21 mA / cm² is required to completely degrade algal cells within 45 minutes. Considering removal efficiency and energy consumption, this is necessary. 2 The current density is best suited for this system.

[0069] Figure 8 This is a graph showing the removal efficiency of Microcystis aeruginosa under different pH conditions in Example 4. Figure 8 It was found that the optimal pH for removing algal cells within 10 minutes was pH=7, with a removal rate of 45.2%. Algal cells could be completely removed within 45 minutes, with significantly better removal efficiency under acidic conditions than under alkaline conditions. Under acidic conditions, electrolytes can reduce the electrostatic repulsion between cyanobacterial cells, promoting algal floc sedimentation. However, compared to neutral conditions, the surface of magnetic materials becomes acidified under acidic conditions, leading to changes in surface charge. Under acidic conditions, the surface charge of magnetic materials is mostly positive, while most pollutants are negatively charged. Therefore, the interaction between the two is weakened, which may be a potential reason why magnetic materials have a superior algae removal ability under neutral conditions.

[0070] Figure 9 This is a staining image of algal cells under a confocal microscope. Observation results show that the control group... Figure 9 The presence of very little green fluorescence in chlorophyll a indicates that most algal cells are active. After 5 minutes of system operation, green fluorescence appears, indicating that some algal cells have undergone apoptosis. After 10 minutes, a large number of cells emit yellow fluorescence, while the red fluorescence gradually decreases, indicating cell death, but chlorophyll a and cell structure remain intact. Subsequently, the red fluorescence gradually weakens, and after 15 minutes, the nucleic acids of most dead algal cells are significantly stained with green fluorescence. In summary, these results demonstrate that the three-dimensional electrochemical magnetic cellulose system can effectively remove Microcystis aeruginosa from water.

[0071] Figure 10 The three-dimensional fluorescence spectrum of extracellular organic compounds is shown by... Figure 10 Initially, distinct peaks A (dissolved microbial metabolites) and B (aromatic proteins) were observed, indicating that the algal cells were active and undergoing normal physiological metabolism. After 5 minutes of operation of the three-dimensional electrochemical magnetic cellulose system, peak B almost disappeared, while peaks C and D appeared, indicating the large-scale production of humic acid and fulleric acid, representing algal cell apoptosis. With continued system operation, the amount of dissolved microbial metabolites gradually decreased, while the content of humic acid and fulleric acid showed a trend of first decreasing, then increasing, and then decreasing again, indicating that the system has the ability to induce algal cell apoptosis and degrade humic acid and fulleric acid. After 45 minutes, the peak values ​​of A, C, and D decreased significantly, indicating a large amount of organic matter degradation within the system.

[0072] Figure 11 The images show the characterization of magnetic cellulose, including infrared spectroscopy, XRD, magnetic testing, and cycling tests. These tests demonstrate the successful preparation of magnetic cellulose and its good recyclability and reusability.

[0073] Figure 12 This is a pathway diagram of *Microcystis aeruginosa* degrading algal cells in a magnetic cellulose electrocoagulation system; by Figure 12 It is known that magnetic cellulose and algal cells can aggregate together under the action of electric current, thereby achieving electrocoagulation and algae removal; in addition, magnetic cellulose particles are both catalysts and electron donors, not only forming ·OH by decomposing hydrogen peroxide, but also generating ·OH on the anode surface through the electrochemical oxidation of water; O2· - O2 can be generated through the reaction of H2O2 with ·OH, or by reducing O2 using magnetic cellulose particle electrodes. Electrons are transferred through oxygen-containing functional groups (-COOH, -OH) on the cellulose material to produce O2·. - The functional groups on magnetic cellulose act as electron shuttles. Furthermore, the active species HO2· and O2· - It also helps produce singlet oxygen. 1O2. In summary, ·OH and 1 O2 had a significant impact on the oxidation system studied.

[0074] The above-described specific embodiments are preferred embodiments of the present invention and are not intended to limit the present invention. Any other changes or equivalent substitutions made without departing from the technical solution of the present invention are included within the protection scope of the present invention.

Claims

1. A method for removing Microcystis aeruginosa based on a magnetic cellulose electrocoagulation system, characterized in that, Includes the following steps: A magnetic cellulose electrocoagulation system was constructed by adding magnetic cellulose with a concentration of 0.02–0.04 g / L to an electrolyte, using mesh electrodes PbO2-Ti and Ti as the anode and cathode, respectively. The electrocoagulation system is electrolyzed for 1–45 min by passing an electric current through it; the electrolyte is a mixture of algae to be removed and supporting electrolyte. The algae to be removed is Microcystis aeruginosa; The method for preparing the magnetic cellulose includes the following steps: Magnetic cellulose was prepared by mixing cellulose, FeCl2-4H2O and FeCl3-6H2O, dissolving them in deionized water, slowly adding ammonia, and finally washing and drying. Fe 2+ and Fe 3+ The molar ratio is 1:2 to 3, and the volume ratio of the deionized water to the ammonia water is 120:15 to 20.

2. The method for removing Microcystis aeruginosa based on a magnetic cellulose electrocoagulation system according to claim 1, characterized in that, The pH value of the electrolyte is 3 to 11.

3. The method for removing Microcystis aeruginosa based on a magnetic cellulose electrocoagulation system according to claim 1, characterized in that, The cellulose was extracted from Napier grass using the nitric acid-ethanol method.

4. The method for removing Microcystis aeruginosa based on a magnetic cellulose electrocoagulation system according to claim 1, characterized in that, The supporting electrolyte includes one of anhydrous sodium sulfate, potassium nitrate, or a mixed solution of potassium ferricyanide and potassium chloride.

5. The method for removing Microcystis aeruginosa based on a magnetic cellulose electrocoagulation system according to claim 1, characterized in that, The current density during the electrolysis process is 7–35 mA / cm². 2 .

6. The method for removing Microcystis aeruginosa based on a magnetic cellulose electrocoagulation system according to claim 1, characterized in that, The concentration of the *Microcystis aeruginosa* was 2–6 x 10⁻⁶. 6 cells / ml.

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