A method for chemically welding manganese oxide modified ceramic membrane

Abstract

A method for chemically welding a manganese oxide modified ceramic membrane, which belongs to the field of drinking water purification and wastewater pollution control, and specifically relates to a method for chemically welding a manganese oxide modified ceramic membrane. The purpose of the present invention is to solve the problem that the thickness of the existing modified membrane is difficult to control and the uniformity of the modified membrane is poor. Method: 1. Pretreatment of the ceramic membrane; 2. Prefabricated liquid is prepared; 3. The ceramic membrane is fixed; 4. The prefabricated liquid is pressed into the membrane surface and the membrane pores by nitrogen; 5. Step 4 is repeated; 6. Potassium permonosulfate solution is pressed into the membrane surface and the membrane pores by nitrogen; 7. Step 5 is repeated; 8. The modified ceramic membrane is stored in deionized water to obtain a chemically welded manganese oxide modified ceramic membrane. The manganese oxide particle modified membrane prepared by the present invention improves the hydrophilicity and dynamic anti-pollution performance of the ceramic membrane. The present invention can obtain a chemically welded manganese oxide modified ceramic membrane.

Description

Technical Field

[0001] The invention belongs to the field of drinking water purification and wastewater pollution control, and specifically relates to a method for chemically welding a manganese oxide modified ceramic membrane. Background Art

[0002] Ceramic membranes are considered to be ideal catalyst substrates due to their high chemical stability and long service life, and have broad application prospects in the field of water treatment. Compared with polymer membranes, ceramic membranes have obvious advantages, such as higher flux, acid and alkali resistance, better thermal stability, mechanical stability and chemical stability, and longer membrane life. Ceramic membranes can be divided into flat ceramic membranes, tubular ceramic membranes and hollow fiber membranes according to the appearance of the components. Among them, flat ceramic membranes are mostly used for the treatment of aqueous solutions and have a three-layer structure: support layer, transition layer and separation membrane layer.

[0003] Ceramic membranes have been widely used in many fields (wastewater treatment, seawater distillation and drinking water disinfection, etc.). Many scholars have done a lot of research on the use of ceramic membranes to treat various types of wastewater, such as oily wastewater, papermaking wastewater, electroplating wastewater and dye wastewater, and have achieved good treatment results. However, the filtration effect of ceramic membranes is greatly affected by water quality. When there are high levels of suspended solids, organic matter and other pollutants in the influent, the membrane filtration effect will be affected, and more frequent cleaning and maintenance are required. Once the ceramic membrane is contaminated or damaged, in order to ensure the smooth operation of the ceramic membrane, the necessary backwashing, chemical cleaning and even replacement of the membrane assembly often increase costs. By preparing a hydrophilic modification layer with a flexibly adjustable thickness, the pollution of the ceramic membrane can be improved, the hydrophobicity of its surface can be reduced, and the hydrophilicity can be improved.

[0004] At present, the commonly used methods for modifying ceramic membranes include sol-gel method, physical / chemical vapor deposition method, etc. The sol-gel method is to mix metal organic compounds with ceramic precursors to form a soluble sol. It is then gelled by heating and then heat treated to prepare a ceramic membrane. The vapor deposition method uses high-energy ion beams or arcs to evaporate metal materials onto the ceramic surface to form a thin film. However, the thickness of the modified membranes prepared by these methods is difficult to control. During the deposition process, the position of the evaporation source and the heat distribution may result in poor uniformity of the deposited ceramic membrane. Therefore, how to improve the water flux and anti-pollution performance of the membrane through a gentle, stable and convenient modification method is a research focus in the field of membrane separation. Summary of the invention

[0005] The purpose of the present invention is to solve the problem that the thickness of the existing modified membrane is difficult to control and the uniformity of the modified membrane is poor, and to provide a method for chemically welding a manganese oxide modified ceramic membrane.

[0006] Under normal temperature conditions, manganese oxide particles generated only by potassium permanganate and manganese sulfate are not dense enough. Therefore, the present invention proposes to use alkali activation to catalytically activate permonosulfate to produce active species, and regulate the pore structure and nanoscale of the manganese oxide layer under the attack of the active species and the spatial confinement of the ceramic membrane; the thickness of the modified layer can be flexibly regulated by different permonosulfate concentrations, the hydrophilicity of the ceramic membrane is improved, and the defects of the solid-state sintering method are solved at the same time. Combined with the degradation of pollutants by active species generated by catalytic oxidation, the anti-pollution and self-cleaning capabilities of the ceramic membrane are improved, laying a foundation for its research in the fields of drinking water purification and wastewater pollution control.

[0007] A method for chemically welding a manganese oxide modified ceramic membrane is accomplished by the following steps:

[0008] 1. Pretreatment of ceramic membrane:

[0009] First, the ceramic membrane is immersed in hydrochloric acid, then taken out, and the hydrochloric acid on the surface of the membrane is rinsed clean with deionized water, and finally immersed in deionized water to obtain a pretreated ceramic membrane;

[0010] 2. Prepare the prefabricated liquid:

[0011] First, the pH value of deionized water is adjusted, and then potassium permanganate and manganese sulfate are added to the deionized water after the pH value is adjusted, and stirred for a period of time to obtain a prefabricated solution;

[0012] 3. Fix the pretreated ceramic membrane on the card slot in the filter device;

[0013] 4. Pour the prefabricated liquid into the filtration device described in step 3, start the filtration device, and allow the prefabricated liquid to enter the filtration device through the water inlet, so that the ceramic membrane is immersed in the prefabricated liquid. Nitrogen is introduced into the prefabricated liquid, and the prefabricated liquid is pressed into the membrane surface and membrane pores by the nitrogen. The reaction lasts for 30 minutes to 60 minutes, and the filtration device is closed;

[0014] The ratio of the volume of the prefabricated liquid described in step 4 to the surface area of ​​the ceramic membrane is (3.0L-4.0L): 300cm 2 ;

[0015] 5. Repeat step 4 0 to 4 times;

[0016] 6. Chemical welding:

[0017] The pH value of the potassium peroxymonosulfate solution is adjusted to 9, and the potassium peroxymonosulfate solution with a pH value of 9 is poured into the filtration device described in step 4, and the filtration device is started, and the potassium peroxymonosulfate solution enters the filtration device through the water inlet, so that the ceramic membrane is immersed in the potassium peroxymonosulfate solution, and nitrogen is introduced into the potassium peroxymonosulfate solution. The potassium peroxymonosulfate solution is pressed into the membrane surface and the membrane pores by the nitrogen gas, and the reaction is carried out for 30 minutes to 60 minutes, and the filtration device is closed;

[0018] The volume ratio of the potassium peroxymonosulfate solution described in step 6 to the surface area of ​​the ceramic membrane is (3.0L-4.0L): 300cm 2 ;

[0019] 7. Repeat step 5 0 to 4 times;

[0020] 8. The modified ceramic membrane is stored in deionized water to obtain a chemically welded manganese oxide modified ceramic membrane.

[0021] Principle of the present invention:

[0022] Chemical welding is a method of bonding metal surfaces together through chemical reactions. It uses the heat energy and chemical composition of chemical reactions to change the properties of the material surface, so that the two materials can be tightly bonded together. The combination of advanced oxidation and ceramic membrane filtration exhibits a synergistic effect of chemical reaction and physical separation. Manganese oxide particles can be fixed on the surface and pore interface of the membrane to avoid catalyst agglomeration and provide more active sites to improve the removal efficiency of organic matter. In addition, during the membrane filtration process, as more reactants are transported to the active sites, the mass transfer capacity can be enhanced. On the other hand, since the active species generated in the process can degrade pollutants, the anti-fouling and self-cleaning capabilities of the ceramic membrane can be improved.

[0023] The present invention innovatively combines the advanced oxidation technology with the membrane water treatment technology. By alkali-activating permonosulfate to produce active species, on the conventional manganese oxide layer (base layer) prepared by potassium permanganate and manganese sulfate, the active species are used to attack the manganese oxide on the base layer, thereby changing the pore structure and nanoscale of the manganese oxide layer, and generating a chemically welded manganese oxide modified ceramic membrane; the thickness of the modified layer can be flexibly changed by changing the concentration of the reagent, and the close bonding between the manganese oxides can be achieved without solid-state sintering. The chemically welded manganese oxide modified ceramic membrane has a good application prospect.

[0024] The present invention has the following effects:

[0025] 1. The modification method of the manganese oxide particles prepared by the present invention is to use alkali activation to catalyze persulfate to generate active species to attack manganese oxide, thereby generating an amorphous manganese oxide layer;

[0026] 2. The preparation method of the manganese oxide particle modified liquid prepared by the present invention is simple, controllable, short in cycle and low in cost;

[0027] 3. The manganese oxide particle modified membrane prepared by the present invention improves the hydrophilicity and dynamic fouling resistance of the ceramic membrane;

[0028] 4. The modified ceramic membrane prepared in the present invention does not require additional high-temperature sintering;

[0029] 5. The modified ceramic membrane prepared in the present invention does not require additional pressurization and energy consumption, and is driven by gravity head to achieve filtration. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a front view of the filtering device described in step 3 of Example 1;

[0031] Figure 2 It is a left side view of the filtering device described in step 3 of Example 1;

[0032] Figure 3 A top view of the filtering device described in step 3 of Example 1;

[0033] Figure 4 This is a physical picture of the filtering device described in step 3 of Example 1;

[0034] Figure 5 To observe the effect of adding different concentrations of potassium persulfate on the particle size of manganese oxides at the nanoscale;

[0035] Figure 6 To observe the effect of adding different concentrations of potassium persulfate on the particle size of generated manganese oxides at micrometer scale;

[0036] Figure 7 1 is a SEM image, in which 1 is the manganese oxide layer obtained in step 4 of Example 1, and 2 is the chemically welded manganese oxide modified ceramic film layer prepared in step 8 of Example 1. DETAILED DESCRIPTION

[0037] Specific implementation method 1: In this implementation method, a method for chemically welding a manganese oxide modified ceramic membrane is completed by the following steps:

[0038] 1. Pretreatment of ceramic membrane:

[0039] First, the ceramic membrane is immersed in hydrochloric acid, then taken out, and the hydrochloric acid on the surface of the membrane is rinsed clean with deionized water, and finally immersed in deionized water to obtain a pretreated ceramic membrane;

[0040] 2. Prepare the prefabricated liquid:

[0041] First, the pH value of deionized water is adjusted, and then potassium permanganate and manganese sulfate are added to the deionized water after the pH value is adjusted, and stirred for a period of time to obtain a prefabricated solution;

[0042] 3. Fix the pretreated ceramic membrane on the card slot in the filter device;

[0043] 4. Pour the prefabricated liquid into the filtration device described in step 3, start the filtration device, and allow the prefabricated liquid to enter the filtration device through the water inlet, so that the ceramic membrane is immersed in the prefabricated liquid. Nitrogen is introduced into the prefabricated liquid, and the prefabricated liquid is pressed into the membrane surface and membrane pores by the nitrogen. The reaction lasts for 30 minutes to 60 minutes, and the filtration device is closed;

[0044] The ratio of the volume of the prefabricated liquid described in step 4 to the surface area of ​​the ceramic membrane is (3.0L-4.0L): 300cm 2 ;

[0045] 5. Repeat step 4 0 to 4 times;

[0046] 6. Chemical welding:

[0047] The pH value of the potassium peroxymonosulfate solution is adjusted to 9, and the potassium peroxymonosulfate solution with a pH value of 9 is poured into the filtration device described in step 4, and the filtration device is started, and the potassium peroxymonosulfate solution enters the filtration device through the water inlet, so that the ceramic membrane is immersed in the potassium peroxymonosulfate solution, and nitrogen is introduced into the potassium peroxymonosulfate solution. The potassium peroxymonosulfate solution is pressed into the membrane surface and the membrane pores by the nitrogen gas, and the reaction is carried out for 30 minutes to 60 minutes, and the filtration device is closed;

[0048] The volume ratio of the potassium peroxymonosulfate solution described in step 6 to the surface area of ​​the ceramic membrane is (3.0L-4.0L): 300cm 2 ;

[0049] 7. Repeat step 5 0 to 4 times;

[0050] 8. The modified ceramic membrane is stored in deionized water to obtain a chemically welded manganese oxide modified ceramic membrane.

[0051] Specific implementation method 2: This implementation method is different from specific implementation method 1 in that: in step 1, the ceramic membrane is first immersed in 2% hydrochloric acid for 5 to 15 minutes, then taken out, and the hydrochloric acid on the membrane surface is rinsed with deionized water, and finally immersed in deionized water for 24 hours to obtain a pretreated ceramic membrane. The other steps are the same as those in specific implementation method 1.

[0052] Specific implementation method 3: This implementation method is different from specific implementation method 1 or 2 in that the ceramic membrane described in step 1 is aluminum oxide, and the size of the ceramic membrane is 10 cm×15 cm. The other steps are the same as those of specific implementation method 1 or 2.

[0053] Specific embodiment 4: This embodiment differs from specific embodiments 1 to 3 in that: in step 2, a sodium hydroxide solution with a concentration of 1 mol / L is used to adjust the pH value of deionized water to 9. The other steps are the same as those of specific embodiments 1 to 3.

[0054] Specific embodiment 5: This embodiment differs from specific embodiments 1 to 4 in that the concentration of potassium permanganate in the prefabricated solution in step 2 is 5 μmol / L, and the concentration of manganese sulfate is 50 μmol / L. The other steps are the same as those of specific embodiments 1 to 4.

[0055] Specific implementation method 6: This implementation method is different from specific implementation methods 1 to 5 in that the stirring speed in step 2 is 700 r / min and the stirring time is 30 min. The other steps are the same as those of specific implementation methods 1 to 5.

[0056] Specific implementation 7: This implementation is different from specific implementations 1 to 6 in that: the filtering device described in step 3 is composed of a box, a slot, a water inlet hole 1, a water outlet hole 2, an overflow hole 3 and a cover plate 4; the slot is arranged inside the box, the top of the box is provided with a cover plate 4, the opposite side walls of the box are provided with a water inlet hole 1 and a water outlet hole 2, and the overflow hole 3 is provided above the water outlet hole 2; the ceramic membrane is fixed on the slot and is connected to the water inlet hole 1 and the water outlet hole 2, respectively; the size of the filtering device is 24.7cm×22.5cm×8cm in length×width×height. The other steps are the same as those of specific implementations 1 to 6.

[0057] Specific embodiment 8: This embodiment differs from specific embodiments 1 to 7 in that in step 6, the pH value of the potassium peroxymonosulfate solution is adjusted to 9 using a sodium hydroxide solution with a concentration of 0.1 mol / L or 1 mol / L. The other steps are the same as those of specific embodiments 1 to 7.

[0058] Specific embodiment 9: This embodiment differs from specific embodiments 1 to 8 in that the concentration of the potassium peroxymonosulfate solution in step 6 is 5 μmol / L to 20 μmol / L. The other steps are the same as those of specific embodiments 1 to 8.

[0059] Specific embodiment 10: This embodiment differs from specific embodiments 1 to 9 in that the reaction time in step 6 is 30 to 60 minutes. The other steps are the same as those in specific embodiments 1 to 9.

[0060] The following examples are used to verify the beneficial effects of the present invention:

[0061] Embodiment 1: A method for chemically welding a manganese oxide modified ceramic membrane is accomplished by the following steps:

[0062] 1. Pretreatment of ceramic membrane:

[0063] First, the ceramic membrane was immersed in 2% hydrochloric acid for 10 minutes, then taken out, and the hydrochloric acid on the surface of the membrane was rinsed with deionized water, and finally immersed in deionized water for 24 hours to obtain a pretreated ceramic membrane;

[0064] The ceramic membrane described in step 1 is aluminum oxide, and the size of the ceramic membrane is 10 cm×15 cm;

[0065] 2. Prepare the prefabricated liquid:

[0066] First, the pH value of deionized water was adjusted to 9, and then potassium permanganate and manganese sulfate were added to the deionized water with a pH value of 9, and finally stirred at a stirring speed of 700 r / min for 30 minutes to obtain a prefabricated liquid;

[0067] The concentration of potassium permanganate in the preformed solution in step 2 is 5 μmol / L, and the concentration of manganese sulfate is 50 μmol / L;

[0068] 3. Fix the pretreated ceramic membrane on the card slot in the filter device;

[0069] 4. Pour the prefabricated liquid into the filtration device described in step 3, start the filtration device, and allow the prefabricated liquid to enter the filtration device through the water inlet, so that the ceramic membrane is immersed in the prefabricated liquid. Nitrogen is introduced into the prefabricated liquid, and the prefabricated liquid is pressed into the membrane surface and membrane pores by the nitrogen. The reaction lasts for 40 minutes, and the filtration device is closed;

[0070] The ratio of the volume of the prefabricated liquid described in step 4 to the surface area of ​​the ceramic membrane is 2.0 L:300 cm 2 ;

[0071] 5. Repeat step 4 0 times;

[0072] 6. Chemical welding:

[0073] The pH value of the potassium peroxymonosulfate solution is adjusted to 9, 2 L of the potassium peroxymonosulfate solution with a pH value of 9 is poured into the filtration device described in step 4, the filtration device is started, the potassium peroxymonosulfate solution enters the filtration device through the water inlet, the ceramic membrane is immersed in the potassium peroxymonosulfate solution, nitrogen is introduced into the potassium peroxymonosulfate solution, the potassium peroxymonosulfate solution is pressed into the membrane surface and the membrane pores by nitrogen, the reaction is carried out for 40 minutes, the filtration device is closed, and the reaction is carried out for another 60 minutes to obtain a modified ceramic membrane;

[0074] The concentration of the potassium peroxymonosulfate solution in step 6 is 20 μmol / L;

[0075] In step 6, the pH value of the potassium peroxymonosulfate solution is adjusted to 9 using a sodium hydroxide solution having a concentration of 1 mol / L;

[0076] 7. Repeat step 50 times;

[0077] 8. The modified ceramic membrane is stored in deionized water to obtain a chemically welded manganese oxide modified ceramic membrane.

[0078] The filtering device described in step 3 of Example 1 is composed of a box body, a card slot, a water inlet hole 1, a water outlet hole 2, an overflow hole 3 and a cover plate 4; the card slot is arranged inside the box body, a cover plate 4 is arranged on the top of the box body, a water inlet hole 1 and a water outlet hole 2 are arranged on the opposite side walls of the box body, and an overflow hole 3 is arranged above the water outlet hole 2; the ceramic membrane is fixed on the card slot and is connected to the water inlet hole 1 and the water outlet hole 2 respectively; the size of the filtering device is 24.7cm×22.5cm×8cm in length×width×height;

[0079] In Example 1, the diameter of the water inlet hole 1 is 8 mm, the diameter of the water outlet hole 2 is 8 mm, the diameter of the overflow hole 3 is 10 mm, and the cover plate 4 is a pull-out cover plate with a size of 250 mm×110 mm.

[0080] Example 2: The difference between this example and Example 1 is that the concentration of the potassium peroxymonosulfate solution in step 6 is 0 μmol / L. The other steps and parameters are the same as those in Example 1.

[0081] Example 3: The difference between this example and Example 1 is that the concentration of the potassium peroxymonosulfate solution in step 6 is 5 μmol / L. The other steps and parameters are the same as those in Example 1.

[0082] Example 4: This example is different from Example 1 in that the concentration of the potassium peroxymonosulfate solution in step 6 is 10 μmol / L. The other steps and parameters are the same as those in Example 1.

[0083] Figure 1 It is a front view of the filtering device described in step 3 of Example 1;

[0084] Figure 2 It is a left side view of the filtering device described in step 3 of Example 1;

[0085] Figure 3 A top view of the filtering device described in step 3 of Example 1;

[0086] Figure 4 This is a physical picture of the filtering device described in step 3 of Example 1;

[0087] Figure 5To observe the effect of adding different concentrations of potassium persulfate on the particle size of manganese oxides at the nanoscale;

[0088] Depend on Figure 5 It can be seen that before the addition of potassium permonosulfate, the particle size distribution of manganese oxide is concentrated at 620nm. After the addition of potassium permonosulfate, the particle size of the manganese oxide particles generated is reduced, and with the increase of the concentration of potassium permonosulfate, the particle size distribution of manganese oxide moves to a smaller particle size, indicating that the addition of potassium permonosulfate can block the growth of small manganese oxide particles and help generate smaller-scale nanoparticle manganese oxide.

[0089] Figure 6 To observe the effect of adding different concentrations of potassium persulfate on the particle size of generated manganese oxides at micrometer scale;

[0090] Depend on Figure 6 It can be seen that: it can be found that in the high-scale range, the addition of persulfate can increase the particle size of manganese oxide. This is because persulfate can complex with manganese oxide and chemically weld small particles of manganese oxide to form large agglomerates.

[0091] Figure 7 1 is a SEM image, in which 1 is the manganese oxide layer obtained in step 4 of Example 1, and 2 is the chemically welded manganese oxide modified ceramic film layer prepared in step 8 of Example 1.

[0092] Depend on Figure 7 It can be seen that the manganese oxide in the prefabricated liquid is in the form of rods, with fewer and disordered pores. After adding persulfate to produce chemical welding under alkaline conditions, the manganese oxide modified layer becomes more dense, the pores of the manganese oxide layer increase significantly and are arranged more neatly, and the surface becomes smoother and has fewer defects compared to the unmodified prefabricated liquid. This is because the manganese oxide oxidizes faster under alkaline conditions and tends to grow into a lamellar structure.

[0093] The original membrane (aluminum oxide ceramic membrane) and the chemically welded manganese oxide modified ceramic membrane prepared in Example 1 were subjected to pollutant filtration experiments; wherein the pollutant configuration step was: 10 mg / L humic acid was added to deionized water, stirred evenly, and a humic acid contaminated liquid was obtained, and a filtration experiment was performed with a gravity head of 18 cm. The tested 10 mg / L humic acid TOC content was 6.79 mg / L, and the TOC of the solution after filtration by the original membrane and the chemically welded manganese oxide modified ceramic membrane prepared in Example 1 were 4.74 mg / L and 1.40 mg / L, respectively; thus, it can be judged that the chemically welded manganese oxide modified ceramic membrane has an enhanced ability to intercept polluted liquid after modification.

Claims

1. A method for chemically welding a manganese oxide modified ceramic membrane, characterized in that This method is completed in the following steps:

1. Pretreatment of ceramic membrane: First, the ceramic membrane is immersed in hydrochloric acid, then taken out, and the hydrochloric acid on the surface of the membrane is rinsed clean with deionized water, and finally immersed in deionized water to obtain a pretreated ceramic membrane; 2. Prepare the prefabricated liquid: First, the pH value of deionized water is adjusted, and then potassium permanganate and manganese sulfate are added to the deionized water after the pH value is adjusted, and stirred for a period of time to obtain a prefabricated solution; 3. Fix the pretreated ceramic membrane on the card slot in the filter device; 4. Pour the prefabricated liquid into the filtration device described in step 3, start the filtration device, and allow the prefabricated liquid to enter the filtration device through the water inlet, so that the ceramic membrane is immersed in the prefabricated liquid. Nitrogen is introduced into the prefabricated liquid, and the prefabricated liquid is pressed into the membrane surface and membrane pores by the nitrogen. The reaction lasts for 30 minutes to 60 minutes, and the filtration device is closed; The ratio of the volume of the prefabricated liquid described in step 4 to the surface area of ​​the ceramic membrane is (3.0L~4.0L): 300cm 2 ; 5. Repeat step 4 0~4 times; 6. Chemical welding: The pH value of the potassium peroxymonosulfate solution is adjusted to 9, and the potassium peroxymonosulfate solution with a pH value of 9 is poured into the filtration device described in step 4, and the filtration device is started, and the potassium peroxymonosulfate solution enters the filtration device through the water inlet, so that the ceramic membrane is immersed in the potassium peroxymonosulfate solution, and nitrogen is introduced into the potassium peroxymonosulfate solution. The potassium peroxymonosulfate solution is pressed into the membrane surface and the membrane pores by the nitrogen gas, and the reaction is carried out for 30 minutes to 60 minutes, and the filtration device is closed; The volume ratio of the potassium peroxymonosulfate solution described in step 6 to the surface area of ​​the ceramic membrane is (3.0L~4.0L): 300cm 2 ; 7. Repeat step 6 0~4 times; 8. The modified ceramic membrane is stored in deionized water to obtain a chemically welded manganese oxide modified ceramic membrane.

2. A method for chemically welding a manganese oxide modified ceramic membrane according to claim 1, characterized in that In step 1, the ceramic membrane is first immersed in 2% hydrochloric acid for 5 minutes to 15 minutes, then taken out, and the hydrochloric acid on the surface of the membrane is rinsed with deionized water, and finally immersed in deionized water for 24 hours to obtain a pretreated ceramic membrane.

3. A method for chemically welding a manganese oxide modified ceramic membrane according to claim 1, characterized in that The ceramic membrane described in step 1 is aluminum oxide, and the size of the ceramic membrane is 10cm×15cm.

4. The method for chemically welding a manganese oxide modified ceramic membrane according to claim 1, characterized in that In step 2, the pH value of the deionized water is adjusted to 9 using a sodium hydroxide solution with a concentration of 1 mol / L.

5. The method for chemically welding a manganese oxide modified ceramic membrane according to claim 1, characterized in that The concentration of potassium permanganate in the prefabricated solution in step 2 is 5 μmol / L, and the concentration of manganese sulfate is 50 μmol / L.

6. The method for chemically welding a manganese oxide modified ceramic membrane according to claim 1, characterized in that The stirring speed in step 2 is 700 r / min, and the stirring time is 30 min.

7. The method for chemically welding a manganese oxide modified ceramic membrane according to claim 1, characterized in that The filtering device described in step three is composed of a box body, a slot, a water inlet hole (1), a water outlet hole (2), an overflow hole (3) and a cover plate (4); the slot is arranged inside the box body, the top of the box body is provided with a cover plate (4), the side walls on both sides of the box body are provided with water inlet holes (1) and water outlet holes (2), and the overflow hole (3) is provided above the water outlet hole (2); the ceramic membrane is fixed on the slot and is connected to the water inlet hole (1) and the water outlet hole (2), respectively; the size of the filtering device is 24.7 cm in length × 22.5 cm in width × 8 cm in height.

8. The method for chemically welding a manganese oxide modified ceramic membrane according to claim 1, characterized in that In step six, the pH value of the potassium permonosulfate solution is adjusted to 9 using a sodium hydroxide solution having a concentration of 0.1 mol / L or 1 mol / L.

9. The method for chemically welding a manganese oxide modified ceramic membrane according to claim 1, characterized in that The concentration of the potassium peroxymonosulfate solution described in step 6 is 5 μmol / L to 20 μmol / L.

Images