Preparation method of Fe-C hollow fiber ceramic membrane

Abstract

The invention discloses a preparation method of a Fe-C hollow fiber ceramic membrane, and belongs to the field of drinking water purification and wastewater pollution treatment. The invention aims to solve the problems of easy agglomeration, inactivation and loss when nanoparticles are loaded on the surface of the membrane. The method comprises the following steps: 1, preparing a hollow fiber ceramic membrane; 2, glue-sealing two ends of the hollow fiber membrane; 3, preparing a Na3BTC solution; 4, preparing a FeCl3 solution; 5, cleaning the surface of the membrane; 6, dipping; and 7, calcining. The method for preparing the Fe-coated C hollow fiber ceramic membrane is simple, easy to operate, low in cost, environmentally friendly, harmless to human health and suitable for large-scale preparation; the Fe-coated C hollow fiber ceramic membrane prepared by the method has no obvious pore diameter blocking phenomenon, and the Fe element is uniformly distributed on the surface of the membrane. According to the invention, the Fe-C hollow fiber ceramic membrane can be obtained.

Description

Technical Field

[0001] This invention belongs to the field of drinking water purification and wastewater pollution control, specifically relating to a method for preparing Fe@C hollow fiber ceramic membrane. Background Technology

[0002] Membrane separation technology, as a separation method that combines environmental friendliness and high efficiency, is highly favored in the field of water treatment. Ceramic membranes have more stable chemical properties and strong oxidation resistance, but their pore size is relatively large, resulting in insufficient separation precision and failing to meet water treatment requirements. The preparation of catalytic membranes by loading catalysts onto ceramic membranes, combined with advanced oxidation technologies, can achieve complementary advantages and improve treatment capacity, making it a hot trend. Catalytic membranes are mainly divided into those using membrane materials to immobilize nanocatalysts or those using catalysts as membrane substrates. The types of catalysts mainly include single-metal oxides (iron oxides, manganese oxides, etc.), bimetallic oxides, non-metallic oxides (GO, CNTs, etc.), and composite materials.

[0003] However, when nanocatalysts are supported on membranes, particle aggregation and pore blockage can easily occur, affecting catalytic performance and permeability. The weak bonding between the catalyst and the membrane substrate makes it prone to deactivation and loss, making it difficult to maintain stable catalytic performance. Therefore, ensuring uniform distribution of nanoparticles and effectively suppressing catalyst loss are current research priorities. Summary of the Invention

[0004] The purpose of this invention is to solve the problem of easy agglomeration, deactivation, and loss of nanoparticles when loaded on the membrane surface, and to provide a method for preparing Fe@C hollow fiber ceramic membranes.

[0005] A method for preparing Fe@C hollow fiber ceramic membrane, specifically comprising the following steps:

[0006] I. Preparation of hollow fiber ceramic membranes:

[0007] ① Dissolve dihydroxystearate in dimethyl sulfoxide to obtain a mixed solution;

[0008] ② Add alumina powder to the mixed solution, ball mill, and obtain the ball-milled solution;

[0009] ③ Add polyphenylene ether sulfone to the ball-milled solution, and ball-mill again to obtain the casting solution;

[0010] ④ Degas the casting solution under vacuum to obtain the degassed casting solution;

[0011] ⑤ Use the degassed casting solution as the feed solution and deionized water as the core solution to spin fibers to obtain film fibers;

[0012] ⑥ Immerse the membrane fibers in deionized water for phase inversion, remove them, cut them, dry them, and finally fire them in a tube furnace to obtain hollow fiber ceramic membranes.

[0013] II. Sealing both ends of the hollow fiber membrane:

[0014] Use AB glue to seal both ends of the hollow fiber ceramic membrane, and let it stand until the AB glue is completely cured to obtain the sealed hollow fiber membrane.

[0015] III. Preparation of Na3BTC solution:

[0016] Add 1,3,5-pyromellitic acid and sodium hydroxide to deionized water, stir thoroughly to dissolve, and obtain Na3BTC solution;

[0017] IV. Preparation of FeCl3 solution:

[0018] FeCl3 was added to deionized water and stirred until homogeneous to obtain a FeCl3 solution.

[0019] 5. Rinse the sealed hollow fiber membrane with deionized water to obtain a hollow fiber ceramic membrane after removing impurities;

[0020] VI. Impregnation:

[0021] ① Immerse the hollow fiber ceramic membrane, after removing impurities, in Na3BTC solution, then rinse it after removal;

[0022] ② Immerse it again in FeCl3 solution, then rinse it after removing it;

[0023] ③ Repeat steps ① and ② several times, and dry at room temperature to obtain a hollow fiber membrane loaded with Fe-BTC;

[0024] 7. The Fe-BTC-loaded hollow fiber membrane is placed in a tube furnace and calcined at 600℃~800℃ under an Ar atmosphere to obtain the Fe@C hollow fiber ceramic membrane.

[0025] The principle of this invention:

[0026] Catalytic membranes prepared by simply depositing nanoparticles onto a film often suffer from nanoparticle agglomeration and deactivation, and the catalytically active components are easily lost during use. Immobilizing metal nanoparticles within a matrix is ​​one effective way to address this problem. MOFs (Metal-Organic Facility-Fibers) are crystalline materials with a supramolecular porous network structure formed by inorganic nodes and organic linkers. They can serve as excellent templates and precursors for high-temperature pyrolysis preparation of nanostructures. Metal-carbon materials derived from MOFs also retain residual pores from the MOF structure, forming highly active sites and improving electron transfer efficiency. At room temperature, FeCl3 and Na3BTC can be rapidly generated by mixing for 10 minutes. Using this method, a hollow fiber ceramic membrane is repeatedly impregnated with both solutions to generate Fe-BTC in situ on the ceramic membrane surface. After pyrolysis, a Fe@C hollow fiber ceramic membrane is obtained.

[0027] Effects of the invention:

[0028] I. The method for preparing Fe@C hollow fiber ceramic membranes according to this invention is simple, easy to operate, low in cost, environmentally friendly, and harmless to human health, making it suitable for large-scale preparation.

[0029] 2. The Fe@C hollow fiber ceramic membrane prepared by this invention does not show obvious pore blockage, and the Fe element is evenly distributed on the membrane surface.

[0030] III. The Fe@C hollow fiber ceramic membrane prepared in this invention generates Fe3O4 particles and Fe2C on its surface after pyrolysis. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a method for preparing Fe@C hollow fiber ceramic membrane;

[0032] Figure 2 The images show scanning electron microscope (SEM) images and surface color change diagrams of the membranes prepared in Example 1. In the images, (a) is a hollow fiber ceramic membrane, (b) is a hollow fiber membrane loaded with Fe-BTC, (c) is a Fe@C hollow fiber ceramic membrane, and (d) is a surface color change diagram.

[0033] Figure 3 The energy dispersive spectroscopy (EDS) spectrum of the Fe@C hollow fiber ceramic membrane prepared in Example 1 is shown below.

[0034] Figure 4 XRD pattern of Fe@C catalyst powder;

[0035] Figure 5 The wettability test of the Fe@C hollow fiber ceramic membrane prepared in Example 1 is shown in the bar graph, which represents the contact angle. The top of the bar graph shows the droplet morphology on different membranes. The contact angle was measured using the three-point method.

[0036] Figure 6 The figure shows the experimental results of the Fe@C hollow fiber ceramic membrane prepared in Example 1 catalytically oxidizing ozone to remove typical odor substances GSM and 2-MIB from water. Detailed Implementation

[0037] Specific Implementation Method 1: This implementation method is a method for preparing Fe@C hollow fiber ceramic membranes, specifically completed according to the following steps:

[0038] I. Preparation of hollow fiber ceramic membranes:

[0039] ① Dissolve dihydroxystearate in dimethyl sulfoxide to obtain a mixed solution;

[0040] ② Add alumina powder to the mixed solution, ball mill, and obtain the ball-milled solution;

[0041] ③ Add polyphenylene ether sulfone to the ball-milled solution, and ball-mill again to obtain the casting solution;

[0042] ④ Degas the casting solution under vacuum to obtain the degassed casting solution;

[0043] ⑤ Use the degassed casting solution as the feed solution and deionized water as the core solution to spin fibers to obtain film fibers;

[0044] ⑥ Immerse the membrane fibers in deionized water for phase inversion, remove them, cut them, dry them, and finally fire them in a tube furnace to obtain hollow fiber ceramic membranes.

[0045] II. Sealing both ends of the hollow fiber membrane:

[0046] Use AB glue to seal both ends of the hollow fiber ceramic membrane, and let it stand until the AB glue is completely cured to obtain the sealed hollow fiber membrane.

[0047] III. Preparation of Na3BTC solution:

[0048] Add 1,3,5-pyromellitic acid and sodium hydroxide to deionized water, stir thoroughly to dissolve, and obtain Na3BTC solution;

[0049] IV. Preparation of FeCl3 solution:

[0050] FeCl3 was added to deionized water and stirred until homogeneous to obtain a FeCl3 solution.

[0051] 5. Rinse the sealed hollow fiber membrane with deionized water to obtain a hollow fiber ceramic membrane after removing impurities;

[0052] VI. Impregnation:

[0053] ① Immerse the hollow fiber ceramic membrane, after removing impurities, in Na3BTC solution, then rinse it after removal;

[0054] ② Immerse it again in FeCl3 solution, then rinse it after removing it;

[0055] ③ Repeat steps ① and ② several times, and dry at room temperature to obtain a hollow fiber membrane loaded with Fe-BTC;

[0056] 7. The Fe-BTC-loaded hollow fiber membrane is placed in a tube furnace and calcined at 600℃~800℃ under an Ar atmosphere to obtain the Fe@C hollow fiber ceramic membrane.

[0057] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that: the particle size of the alumina powder mentioned in step 1.② is 1μm; the ball milling time mentioned in steps 1.② and 1.③ is 10h~12h. Other steps are the same as in Specific Implementation Method One.

[0058] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that: in step 1 ③, the casting solution contains 1%~2% by mass of dipolyhydroxystearate, 31%~33% by mass of dimethyl sulfoxide, 59%~61% by mass of alumina powder, and 6%~7% by mass of polyphenylene ether sulfone. Other steps are the same as in Specific Implementation Method 1 or 2.

[0059] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that: the vacuum degassing time in step one (④) is 1 to 2 hours; the spinning parameters in step one (⑤) are set as follows: feed liquid flow rate: 7 to 10 mL / min, core liquid flow rate: 10 mL / min, air gap: 10 to 15 cm. Other steps are the same as in Specific Implementation Methods One to Three.

[0060] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in the following ways: the phase transformation time described in step one (⑥) is 20-24 hours; the firing process described in step one (⑥) is as follows: the temperature is increased from room temperature to 550-650°C at a rate of 2°C / min to 5°C / min, held for 1.5-2.5 hours, then increased to 1400-1450°C at a rate of 2°C / min to 5°C / min and held for 1.5-2.5 hours, and finally reduced to room temperature at a rate of 5°C / min; the cutting described in step one (⑥) is as follows: the membrane fibers are cut to 8cm lengths. Other steps are the same as in Specific Implementation Methods One to Four.

[0061] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that: the AB adhesive mentioned in step two was purchased from Dongguan Aibida Biotechnology Co., Ltd.; in step two, the AB adhesive is extruded through a mixing nozzle, and the end of the hollow fiber ceramic membrane is inserted into the adhesive, ensuring that the end face and outer peripheral wall of the end are fully wetted and wrapped by the adhesive, then removed, suspended and fixed, and left to stand until the AB adhesive is completely cured; the concentration of the Na3BTC solution mentioned in step three is 50mmol / L~70mmol / L. Other steps are the same as in Specific Implementation Methods One to Five.

[0062] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that the concentration of the FeCl3 solution mentioned in step four is 30 mmol / L to 50 mmol / L. The other steps are the same as in Specific Implementation Methods One to Six.

[0063] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One to Seven in that the immersion time in steps Six ① and Six ② is 5 to 30 minutes. The other steps are the same as in Specific Implementation Methods One to Seven.

[0064] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that: the rinsing described in steps Six ① and Six ② is done using deionized water; and the number of times mentioned in step Six ③ is 3 to 5 times. The other steps are the same as in Specific Implementation Methods One to Eight.

[0065] Specific Implementation Method Ten: The difference between this implementation method and Specific Implementation Methods One to Nine is that the calcination described in step seven is as follows: the temperature is increased from room temperature to 600℃~800℃ at a heating rate of 2℃ / min, held at that temperature for 1 hour, and then allowed to cool naturally to room temperature. The other steps are the same as in Specific Implementation Methods One to Nine.

[0066] The beneficial effects of the present invention are verified using the following embodiments:

[0067] Example 1: A method for preparing a Fe@C hollow fiber ceramic membrane, characterized in that the preparation method is specifically carried out according to the following steps:

[0068] I. Preparation of hollow fiber ceramic membranes:

[0069] ① Dissolve dihydroxystearate (AP135-PEG-30, purchased from Croda Kelvin) in dimethyl sulfoxide to obtain a mixed solution;

[0070] ② Add alumina powder to the mixed solution, then add grinding balls, and place in a ball mill for 12 hours to obtain the ball-milled solution;

[0071] ③ Add polyphenylene ether sulfone to the ball-milled solution and ball-mill for 12 hours to obtain the casting solution;

[0072] ④ Degas the casting solution under vacuum for 1 hour to obtain the degassed casting solution;

[0073] ⑤ Use the degassed casting solution as the feed solution and deionized water as the core solution to spin fibers to obtain film fibers;

[0074] ⑥ Immerse the membrane fibers in deionized water for phase inversion for 24 hours, remove them and cut them into 8cm long segments, dry them, and finally fire them in a tube furnace to obtain hollow fiber ceramic membrane (base membrane).

[0075] In step 1③, the casting solution contains 1.5% by mass of dihydroxystearate, 32% by mass of dimethyl sulfoxide, 60% by mass of alumina powder, and 6.5% by mass of polyphenylene ether sulfone.

[0076] The alumina powder mentioned in step 1② has a particle size of 1 μm;

[0077] The spinning parameters set in step 1, ⑤ are as follows: feed liquid flow rate: 10 mL / min, core liquid flow rate: 10 mL / min, air gap: 10~15 cm.

[0078] The firing process described in step 1, ⑥ is as follows: the temperature is increased from room temperature to 600℃ at a rate of 2℃ / min, held for 2 hours, then increased to 1450℃ at a rate of 5℃ / min and held for 2 hours, and finally reduced to room temperature at a rate of 5℃ / min.

[0079] II. Sealing both ends of the hollow fiber membrane:

[0080] Use AB glue to seal both ends of the hollow fiber ceramic membrane, and let it stand until the AB glue is completely cured to obtain the sealed hollow fiber membrane.

[0081] The AB glue mentioned in step two was purchased from Dongguan Aibida Biotechnology Co., Ltd.

[0082] In step two, the AB glue is extruded through the mixing nozzle, and the port of the hollow fiber ceramic membrane is inserted into the glue to ensure that the port end face and the outer peripheral wall are fully wetted and wrapped by the glue. Then, it is taken out, suspended and fixed, and left to stand until the AB glue is completely cured.

[0083] III. Preparation of Na3BTC solution:

[0084] Add 1,3,5-pyromellitic acid and sodium hydroxide to deionized water, stir thoroughly to dissolve, and obtain Na3BTC solution;

[0085] The concentration of the Na3BTC solution mentioned in step three is 60 mmol / L;

[0086] IV. Preparation of FeCl3 solution:

[0087] FeCl3 was added to deionized water and stirred until homogeneous to obtain a FeCl3 solution.

[0088] The concentration of the FeCl3 solution mentioned in step four is 40 mmol / L;

[0089] 5. Rinse the sealed hollow fiber membrane with deionized water to obtain a hollow fiber ceramic membrane after removing impurities;

[0090] VI. Impregnation:

[0091] ① Immerse the hollow fiber ceramic membrane, after removing impurities, in Na3BTC solution for 5 minutes, then rinse it.

[0092] ② Immerse in FeCl3 solution for 5 minutes, then rinse.

[0093] ③ Repeat steps ① to ② five times, and dry at room temperature to obtain a hollow fiber membrane loaded with Fe-BTC;

[0094] 7. Place the Fe-BTC loaded hollow fiber membrane into a tube furnace and heat it from room temperature to 700℃ at a heating rate of 2℃ / min under an Ar atmosphere. Hold the temperature for 1 hour and then allow it to cool naturally to room temperature to obtain the Fe@C hollow fiber ceramic membrane (denoted as Fe@C catalytic membrane or Fe@C membrane).

[0095] Figure 1 This is a schematic diagram of a method for preparing Fe@C hollow fiber ceramic membrane;

[0096] Figure 1 The hollow fiber ceramic membrane was prepared by phase inversion method. The Fe-BTC loaded hollow fiber membrane was generated in situ by repeated impregnation in two solutions. The Fe@C hollow fiber ceramic membrane was obtained by pyrolysis of Fe-BTC in an inert gas atmosphere.

[0097] Figure 2 The images show scanning electron microscope (SEM) images and surface color change diagrams of the membranes prepared in Example 1. In the images, (a) is a hollow fiber ceramic membrane, (b) is a hollow fiber membrane loaded with Fe-BTC, (c) is a Fe@C hollow fiber ceramic membrane, and (d) is a surface color change diagram.

[0098] Depend on Figure 2 It can be seen that the particles that make up the original membrane surface are relatively smooth. After loading Fe-BTC, a dense Fe-BTC layer is formed, and the surface pore structure is covered by Fe-BTC. After Ar pyrolysis sintering, the pore structure reappears, and many fine particles can be observed on the surface of the particles that make up the membrane.

[0099] Figure 3The energy dispersive spectroscopy (EDS) spectrum of the Fe@C hollow fiber ceramic membrane prepared in Example 1 is shown below.

[0100] Depend on Figure 3 It can be seen that Fe and C elements are evenly distributed on the film surface before and after firing, and no obvious agglomeration occurs.

[0101] The Fe@C catalyst powder was prepared according to the method in Example 1, specifically by following these steps:

[0102] ① Preparation of Na3BTC solution:

[0103] Add 1,3,5-pyromellitic acid and sodium hydroxide to deionized water, stir thoroughly to dissolve, and obtain Na3BTC solution;

[0104] The concentration of the Na3BTC solution mentioned in step ① is 60 mmol / L;

[0105] ② Preparation of FeCl3 solution:

[0106] FeCl3 was added to deionized water and stirred until homogeneous to obtain a FeCl3 solution.

[0107] The concentration of the FeCl3 solution mentioned in step ② is 40 mmol / L;

[0108] ③ Use a peristaltic pump to add FeCl3 solution dropwise to Na3BTC solution. Allow the mixture to react fully for 10 minutes. Centrifuge at 8000 r / min for 10 minutes each time. Wash the mixture three times with water, anhydrous ethanol, and water to obtain an orange precipitate.

[0109] In step ③, the volume ratio of FeCl3 solution to Na3BTC solution is 1:1;

[0110] ④ The orange precipitate was pre-frozen in the freezer for 12 hours, and then freeze-dried to obtain Fe-BTC orange powder;

[0111] ⑤ Place the Fe-BTC orange powder into a corundum crucible, place it in a tube furnace, and heat it from room temperature to 700℃ at a heating rate of 2℃ / min under an Ar atmosphere. Hold the temperature for 1 hour, and then allow it to cool naturally to room temperature to obtain Fe@C catalyst powder.

[0112] Figure 4 XRD pattern of Fe@C catalyst powder;

[0113] Depend on Figure 4It can be seen that small diffraction peaks of Fe3C can be observed at 37.68°, 39.77°, 40.72°, 42.87°, 43.70°, 44.67°, 45.09°, 45.85°, 48.57°, 49.14°, and 51.87°, corresponding to its (210), (002), (201), (211), (102), (220), (031), (112), (131), (221), and (122) crystal planes, respectively (PDF#77-0225). Diffraction peaks of Fe can also be observed at 44.56°, 64.92°, and 82.31°, corresponding to the (110), (200), and (211) crystal planes, respectively (PDF#99-0064).

[0114] Figure 5 The wettability test of the Fe@C hollow fiber ceramic membrane prepared in Example 1 is shown in the bar graph, which represents the contact angle. The top of the bar graph shows the droplet morphology on different membranes. The contact angle was measured using the three-point method.

[0115] Depend on Figure 5 It can be seen that the contact angle of the original membrane is 27.96°, and after loading modification, the contact angle of the Fe@C hollow fiber ceramic membrane becomes 90.12°, indicating that the presence of Fe@C particles reduces the hydrophilicity of the membrane surface.

[0116] Water containing the odor-causing substance GSM (GSM concentration of 500 ng / L) was treated using hollow fiber ceramic membrane (base membrane) prepared in Example 1, Fe@C membrane, ozone (ozone concentration 2 mg / L), and Fe@C membrane + ozone (ozone concentration 2 mg / L), respectively. The concentration of the odor-causing substance in the water was detected using purge-trap-gas chromatography-mass spectrometry. The GSM removal rate is shown in [Figure 1]. Figure 6 As shown;

[0117] Water containing the odor-causing substance 2-MIB (2-MIB concentration of 500 ng / L) was treated using hollow fiber ceramic membrane (base membrane) prepared in Example 1, Fe@C membrane, ozone (ozone concentration 2 mg / L), and Fe@C membrane + ozone (ozone concentration 2 mg / L), respectively. The concentration of the odor-causing substance in the water was detected using purge-trap-gas chromatography-mass spectrometry. The removal rate of GSM is shown in [Figure missing]. Figure 6 As shown;

[0118] Depend on Figure 6 It can be seen that the base membrane is basically unable to remove GSM and 2-MIB. The removal rates of pure ozone for GSM and 2-MIB are 45.71% and 38.97%, respectively. The removal rates of Fe@C membrane for GSM and 2-MIB are 66.14% and 62.16%, respectively. The combined use of the two can achieve a removal rate of over 90% for GSM and 2-MIB.

Claims

1. A method for preparing a Fe@C hollow fiber ceramic membrane, characterized in that... The preparation method is specifically carried out according to the following steps: I. Preparation of hollow fiber ceramic membranes: ① Dissolve dihydroxystearate in dimethyl sulfoxide to obtain a mixed solution; ② Add alumina powder to the mixed solution, ball mill, and obtain the ball-milled solution; ③ Add polyphenylene ether sulfone to the ball-milled solution, and ball-mill again to obtain the casting solution; ④ Degas the casting solution under vacuum to obtain the degassed casting solution; ⑤ Use the degassed casting solution as the feed solution and deionized water as the core solution to spin fibers to obtain film fibers; ⑥ Immerse the membrane fibers in deionized water for phase inversion, remove them, cut them, dry them, and finally fire them in a tube furnace to obtain hollow fiber ceramic membranes. II. Sealing both ends of the hollow fiber membrane: Use AB glue to seal both ends of the hollow fiber ceramic membrane, and let it stand until the AB glue is completely cured to obtain the sealed hollow fiber membrane. III. Preparation of Na3BTC solution: Add 1,3,5-pyromellitic acid and sodium hydroxide to deionized water, stir thoroughly to dissolve, and obtain Na3BTC solution; IV. Preparation of FeCl3 solution: FeCl3 was added to deionized water and stirred until homogeneous to obtain a FeCl3 solution.

5. Rinse the sealed hollow fiber membrane with deionized water to obtain a hollow fiber ceramic membrane after removing impurities; VI. Impregnation: ① Immerse the hollow fiber ceramic membrane, after removing impurities, in Na3BTC solution, then rinse it after removal; ② Immerse it again in FeCl3 solution, then rinse it after removing it; ③ Repeat steps ① and ② several times, and dry at room temperature to obtain a hollow fiber membrane loaded with Fe-BTC; 7. The Fe-BTC-loaded hollow fiber membrane is placed in a tube furnace and calcined at 600℃~800℃ under an Ar atmosphere to obtain the Fe@C hollow fiber ceramic membrane.

2. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... The alumina powder mentioned in step 1② has a particle size of 1μm; the ball milling time mentioned in steps 1② and 1③ is 10h~12h.

3. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... In step 1③, the casting solution contains 1% to 2% by mass of dihydroxystearate, 31% to 33% by mass of dimethyl sulfoxide, 59% to 61% by mass of alumina powder, and 6% to 7% by mass of polyphenylene ether sulfone.

4. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... The vacuum degassing time mentioned in step 1 ④ is 1h~2h; the spinning parameters mentioned in step 1 ⑤ are set as follows: feed liquid flow rate: 7~10mL / min, core liquid flow rate: 10mL / min, air gap: 10~15cm.

5. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... The phase transformation time mentioned in step 1, ⑥ is 20h~24h; the firing process mentioned in step 1, ⑥ is as follows: the temperature is increased from room temperature to 550℃~650℃ at a heating rate of 2℃ / min~5℃ / min, held for 1.5h~2.5h, then increased to 1400℃~1450℃ at a rate of 2℃ / min~5℃ / min and held for 1.5h~2.5h, and finally reduced to room temperature at a rate of 5℃ / min; the cutting mentioned in step 1, ⑥ is as follows: the membrane filaments are cut into 8cm lengths.

6. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... In step two, the AB glue is extruded through the mixing nozzle, and the port of the hollow fiber ceramic membrane is inserted into the glue, ensuring that the port end face and outer peripheral wall are fully wetted and wrapped by the glue. Then, it is taken out, suspended and fixed, and left to stand until the AB glue is completely cured. The concentration of the Na3BTC solution mentioned in step three is 50mmol / L~70mmol / L.

7. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... The concentration of the FeCl3 solution mentioned in step four is 30 mmol / L to 50 mmol / L.

8. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... The soaking time described in steps 6① and 6② is 5 min to 30 min.

9. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... The rinsing described in steps 6.1 and 6.2 refers to rinsing with deionized water; the number of times mentioned in step 6.3 refers to 3 to 5 times.

10. The method for preparing a Fe@C hollow fiber ceramic membrane according to claim 1, characterized in that... The calcination described in step seven is as follows: the temperature is increased from room temperature to 600℃~800℃ at a heating rate of 2℃ / min, held at that temperature for 1 hour, and then allowed to cool naturally to room temperature.

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