A method for preparing a photocatalytic ceramic flat sheet membrane loaded with Fe-CTF, a product prepared by the method and applications thereof

Abstract

The application relates to the technical field of membrane filtration, and particularly provides a preparation method of a photocatalytic ceramic flat plate membrane loaded with Fe-CTF, a product prepared by the method and application, the preparation method comprises the following steps: injecting an aqueous solution of Fe-CTF composite material to the surface of a blank ceramic flat plate membrane, performing vacuum filtration, and then performing drying and high-temperature calcination, so that the Fe-CTF composite material can be uniformly and efficiently loaded on the ceramic flat plate membrane, the iron is compounded with the CTF, the temperature and the time of calcination are adjusted, the CTF material and the ceramic flat plate membrane reach a high bonding strength, the CTF material is not easy to fall off during work, the excellent filtering performance of the ceramic flat plate membrane can be exerted, the degradation performance of the CTF on organic pollutants can be exerted, and unexpected effects are achieved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of membrane filtration, and particularly relates to a preparation method of a Fe-CTF-loaded photocatalytic ceramic flat membrane, a product prepared by the method and application of the product. BACKGROUND

[0002] China has a large population, uneven distribution of water resources, and an increasingly serious shortage. A large number of lakes and rivers are polluted, further exacerbating China's water resource crisis. Therefore, efficient use of water resources has become a hot and important research topic. Membrane filtration technology is most widely used in the fields of wastewater treatment and seawater desalination.

[0003] Compared with organic membranes, inorganic membranes have excellent thermal stability and pore stability, high mechanical strength, good chemical corrosion resistance, and good recycling performance, and can simultaneously achieve the dual effects of rapid filtration and precision filtration. As a membrane separation material with excellent performance, ceramic flat membranes have been widely used in the field of wastewater treatment. Since toxic pollutants such as organic dyes, antibiotics, phenols and heavy metal ions often exist in wastewater, these pollutants usually have high toxicity, are difficult to degrade and are easy to accumulate, which pose a serious threat to the ecological system and human health. However, ceramic flat membranes cannot efficiently degrade these toxic pollutants. Therefore, the combination of photocatalytic oxidation technology and membrane separation technology has become a research focus in recent years.

[0004] Covalent triazine framework structure (CTF) is a kind of two-dimensional layered polymer composed of aromatic rings and nitrogen-rich triazine rings as connecting units. Due to high specific surface area, adjustable pore structure, suitable band gap and high chemical stability, CTFs are widely used in the field of photocatalysis. However, due to the poor solubility of powdered CTFs, it is difficult to uniformly and efficiently coat this type of material on the surface of inorganic membranes, thereby limiting its application in the field of membrane separation. SUMMARY

[0005] The purpose of the present application is to solve the above problems, and provide a preparation method of a Fe-CTF-loaded photocatalytic ceramic flat membrane, a product prepared by the method and application of the product. The CTF material in the Fe-CTF-loaded photocatalytic ceramic flat membrane reaches a high bonding strength with the ceramic flat membrane, and is not easy to fall off during work. The Fe-CTF-loaded photocatalytic ceramic flat membrane can not only exert the excellent filtration performance of the ceramic flat membrane, but also exert the degradation performance of the CTF on organic pollutants, and has achieved unexpected effects.

[0006] In order to achieve the above purpose, the technical scheme of the present application is as follows:

[0007] A preparation method of a Fe-CTF-loaded photocatalytic ceramic flat membrane, comprising the following steps:

[0008] Step 1, placing a blank ceramic flat membrane into a suction filtration device;

[0009] Step 2, inject the aqueous solution of Fe-CTF composite material to the surface of the ceramic flat sheet membrane under vacuum filtration;

[0010] Step 3, sequentially perform first drying and calcination treatment on the ceramic flat sheet membrane obtained in step 2 to obtain a photocatalytic ceramic flat sheet membrane loaded with Fe-CTF;

[0011] The temperature of the calcination treatment is not less than 400 DEG C, and the time of the calcination treatment is not less than 1 h.

[0012] The application provides a preparation method of a photocatalytic ceramic flat sheet membrane loaded with Fe-CTF. The aqueous solution of Fe-CTF composite material is injected to the surface of a blank ceramic flat sheet membrane, and after vacuum filtration, drying and high-temperature calcination are performed, the Fe-CTF composite material can be uniformly and efficiently loaded on the ceramic flat sheet membrane. The application combines iron and CTF, and adjusts the temperature and time of calcination, so that the CTF material and the ceramic flat sheet membrane have high bonding strength and are not easy to fall off during work. The ceramic flat sheet membrane has excellent filtering performance, and the CTF has degradation performance on organic pollutants, which achieves unexpected effect.

[0013] Further, in step 2, the pressure during filtration is-0.1 to-0.3 Mpa.

[0014] Further, in step 2, the aqueous solution of Fe-CTF composite material is injected to the surface of the ceramic flat sheet membrane in multiple small injections to avoid material loss due to low filtration speed. The injection times are 2-5 times.

[0015] Further, in step 2, the aqueous solution of Fe-CTF composite material is a mixed solution of Fe-CTF composite material and water, and the concentration is 0.5-1 g / L.

[0016] Further, the Fe-CTF composite material is prepared by the following method,

[0017] S1, mix the CTF material with the iron salt solution and stir;

[0018] S2, sequentially perform filtration, second drying, centrifugal washing and third drying treatment on the solution obtained in S1 to obtain the Fe-CTF composite material.

[0019] Further, the carbon content in the CTF material is 50%-55%, the nitrogen content is 15%-20%, and the SSA is 1400-1500 m 2 / g.

[0020] Further, the water solution of the Fe-CTF composite material contains 0.0025-0.005 mol Fe per 50-60 mg CTF. Through a large number of researches of the inventor, it is found that the amount of iron added in the composite material is closely related to the photocatalytic effect and adhesion performance of the photocatalytic ceramic flat plate membrane loaded with Fe-CTF, and too much or too little iron content will affect the performance of the product, preferably, the water solution of the Fe-CTF composite material contains 0.003-0.005 mol Fe per 50-60 mg CTF.

[0021] Further, the iron salt is a ferric chloride solution or a ferric nitrate solution.

[0022] Further, the concentration of the iron salt is 0.05-0.1 mol / L.

[0023] Further, in the step 3, the calcination treatment temperature is 400-600 DEG C. It is found that the calcination treatment temperature directly affects the photocatalytic effect and adhesion performance of the photocatalytic ceramic flat plate membrane loaded with Fe-CTF, and when the calcination temperature is lower than 400 DEG C, the bonding strength of the composite material on the flat plate membrane will be greatly reduced, and the photocatalytic effect will also be reduced, preferably, the calcination treatment temperature is 500-600 DEG C.

[0024] Further, in the step 3, the calcination treatment time is 1-2 h. It is found that the calcination treatment time directly affects the photocatalytic effect and adhesion performance of the photocatalytic ceramic flat plate membrane loaded with Fe-CTF, and when the calcination time is less than 1 h, the bonding strength of the composite material on the flat plate membrane will be greatly reduced, and the photocatalytic effect will also be reduced.

[0025] Further, in the step 3, the heating rate during the calcination treatment is 5-10 DEG C / min.

[0026] Another object of the present application is to provide a product prepared by the above preparation method.

[0027] The photocatalytic ceramic flat plate membrane loaded with Fe-CTF is prepared by the above preparation method.

[0028] Further, the Fe-CTF composite material is uniformly attached to the surface of the ceramic flat plate membrane, and the thickness of the Fe-CTF composite material is 0.1-0.3 mm.

[0029] Another object of the present application is to provide an application of the photocatalytic ceramic flat plate membrane loaded with Fe-CTF.

[0030] The above photocatalytic ceramic flat plate membrane loaded with Fe-CTF is applied in photocatalytic degradation of pollutants.

[0031] In summary, by adopting the technical scheme, the application has the beneficial effects of:

[0032] The application provides a preparation method of a Fe-CTF loaded photocatalytic ceramic flat sheet membrane, a product prepared by the method and an application of the product. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 SEM image of Fe doped CTF in Example 1.

[0034] Figure 2 SEM image of Fe-CTF / ceramic flat sheet membrane in Example 1. DETAILED DESCRIPTION

[0035] The application will be described in detail below with reference to the drawings.

[0036] In order to make the purpose, technical scheme and advantages of the application clearer, the application will be described in further detail below with reference to the drawings and examples.

[0037] Example 1

[0038] The blank ceramic flat sheet membrane was placed in anhydrous ethanol and ultrasonically cleaned for 30 min, then placed in an 80℃ oven for drying and standby.

[0039] The CTF material was mixed with 0.05 mol / L ferric chloride solution and placed on a magnetic stirrer for stirring for 1 h.

[0040] Then, the mixture was filtered, dried, centrifugally washed and dried again to obtain the Fe-CTF composite material; wherein, 0.004 mol of Fe was contained in every 50 mg of CTF.

[0041] The Fe-CTF composite material was added to deionized water and ultrasonically mixed for 30 min to obtain a water solution of the Fe-CTF composite material with a concentration of 0.8 g / L.

[0042] The dried ceramic flat membrane is placed in a filtration device, and the aqueous solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat membrane with a syringe (when injecting the aqueous solution of the Fe-CTF composite material into the surface of the ceramic flat membrane, multiple small injections are performed to avoid material loss due to too low a filtration speed. The number of injections is 2-5 times). Filtration is performed at a pressure of -0.1 MPa until the Fe-CTF composite material is evenly deposited on the membrane.

[0043] The filtered sample was placed in an oven at 80°C for 12 hours, and then placed in a tube furnace for calcination for 2 hours at a calcination temperature of 500°C and a heating rate of 5°C / min. After naturally cooling to room temperature, a photocatalytic ceramic flat film loaded with Fe-CTF was obtained.

[0044] The Fe-CTF and Fe-CTF / photocatalytic ceramic flat membranes prepared in Example 1 were characterized by SEM and Mapping. Figure 1 、 Figure 2 shown.

[0045] Depend on Figure 1 、 Figure 2 It can be seen that CTF is successfully doped with Fe and efficiently and evenly loaded onto the ceramic flat membrane with a loading thickness of 0.2 mm.

[0046] Example 2

[0047] The blank ceramic flat membrane was placed in anhydrous ethanol, ultrasonically cleaned for 30 min, and dried in an oven at 80°C for later use.

[0048] The CTF material was mixed with 0.05 mol / L ferric chloride solution and stirred on a magnetic stirrer for 1 h;

[0049] The mixture was then filtered, dried, centrifuged and washed, and dried again to obtain a Fe-CTF composite material; wherein, every 55 mg of CTF contained 0.005 mol of Fe.

[0050] The Fe-CTF composite material was added into deionized water and thoroughly mixed by ultrasonication for 30 min to obtain an aqueous solution of the Fe-CTF composite material with a concentration of 1 g / L.

[0051] The dried ceramic flat membrane is placed in a filtration device, and the aqueous solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat membrane with a syringe (when injecting the aqueous solution of the Fe-CTF composite material into the surface of the ceramic flat membrane, multiple small injections are performed to avoid material loss due to too low a filtration speed. The number of injections is 2-5 times). Filtration is performed at a pressure of -0.2 MPa until the Fe-CTF composite material is evenly deposited on the membrane.

[0052] The sample after filtration is placed in an 80℃ oven for 12h, and then placed in a tube furnace for calcination for 2h, with a calcination temperature of 400℃ and a heating rate of 8℃ / min. After natural cooling to room temperature, the photocatalytic ceramic flat sheet membrane loaded with Fe-CTF is obtained.

[0053] It is detected that the thickness of the Fe-CTF composite material in the photocatalytic ceramic flat sheet membrane loaded with Fe-CTF is 0.1mm.

[0054] Example 3

[0055] The blank ceramic flat sheet membrane is placed in anhydrous ethanol and ultrasonically cleaned for 30min, and then placed in an 80℃ oven for drying, ready for use.

[0056] The CTF material is mixed with a 0.05mol / L iron chloride solution, and placed on a magnetic stirrer for stirring for 1h.

[0057] Then, the Fe-CTF composite material is obtained by filtration, drying, centrifugal washing, and drying again. Among them, 0.0025mol of Fe is contained in every 60mg of CTF.

[0058] The Fe-CTF composite material is added to deionized water, and ultrasonically mixed for 30min to obtain a water solution of the Fe-CTF composite material with a concentration of 0.5g / L.

[0059] The dried ceramic flat sheet membrane is placed in a filtration device, and the water solution of the Fe-CTF composite material is injected to the surface of the ceramic flat sheet membrane by a syringe (when injecting the water solution of the Fe-CTF composite material to the surface of the ceramic flat sheet membrane, multiple small injections are performed to avoid material loss due to too low filtration speed, and the injection times are 2-5 times), and filtration is performed under a pressure of-0.3Mpa until the Fe-CTF composite material is uniformly deposited on the membrane.

[0060] The sample after filtration is placed in an 80℃ oven for 12h, and then placed in a tube furnace for calcination for 2h, with a calcination temperature of 400℃ and a heating rate of 8℃ / min. After natural cooling to room temperature, the photocatalytic ceramic flat sheet membrane loaded with Fe-CTF is obtained.

[0061] It is detected that the thickness of the Fe-CTF composite material in the photocatalytic ceramic flat sheet membrane loaded with Fe-CTF is 0.3mm.

[0062] Comparative Example 1

[0063] Comparative Example 1 does not add iron element, and directly injects the CTF material to the surface of the ceramic flat sheet membrane, and the operation method and process parameters are the same as those of Example 1, and are as follows:

[0064] The blank ceramic flat sheet membrane was placed in anhydrous ethanol and ultrasonically cleaned for 30 min, and then placed in an oven at 80°C for drying, ready for use.

[0065] The CTF material was added to deionized water and ultrasonically mixed for 30 min to obtain a water solution of the CTF material with a concentration of 0.8 g / L.

[0066] The dried ceramic flat sheet membrane was placed in a suction filtration device, and the water solution of the CTF material was injected onto the surface of the ceramic flat sheet membrane using a syringe (when injecting the water solution of the CTF material onto the surface of the ceramic flat sheet membrane, the injection was performed multiple times in small amounts to avoid material loss due to too low a suction filtration speed, and the injection was performed 2-5 times), and suction filtration was performed at a pressure of -0.1 MPa until the CTF material was uniformly deposited on the membrane.

[0067] The suction-filtered sample was placed in an oven at 80°C for 12 h, and then placed in a tube furnace for calcination at 500°C for 2 h at a temperature rising rate of 5°C / min, and then naturally cooled to room temperature to obtain a photocatalytic ceramic flat sheet membrane loaded with CTF.

[0068] Comparative Example 2

[0069] In Comparative Example 2, the iron element was replaced by manganese, and the Mn-CTF material was injected onto the surface of the ceramic flat sheet membrane, and the operation method and process parameters were the same as in Example 1, and were as follows:

[0070] The blank ceramic flat sheet membrane was placed in anhydrous ethanol and ultrasonically cleaned for 30 min, and then placed in an oven at 80°C for drying, ready for use.

[0071] The CTF material was mixed with a 0.05 mol / L manganese chloride solution, and placed on a magnetic stirrer for stirring for 1 h.

[0072] Then, suction filtration, drying, centrifugal washing, and re-drying were performed to obtain a Mn-CTF composite material; wherein, in every 50 mg of the CTF, 0.004 mol of Mn was contained.

[0073] The Mn-CTF composite material was added to deionized water and ultrasonically mixed for 30 min to obtain a water solution of the Mn-CTF composite material with a concentration of 0.8 g / L.

[0074] The dried ceramic flat sheet membrane was placed in a suction filtration device, and the water solution of the Mn-CTF composite material was injected onto the surface of the ceramic flat sheet membrane using a syringe (when injecting the water solution of the Mn-CTF composite material onto the surface of the ceramic flat sheet membrane, the injection was performed multiple times in small amounts to avoid material loss due to too low a suction filtration speed, and the injection was performed 2-5 times), and suction filtration was performed at a pressure of -0.1 MPa until the Mn-CTF composite material was uniformly deposited on the membrane.

[0075] The sample after suction filtration was placed in an oven at 80°C for 12h, and then calcined in a tube furnace for 2h, with a calcination temperature of 500°C and a heating rate of 5°C / min. After natural cooling to room temperature, the photocatalytic ceramic flat sheet membrane loaded with Mn-CTF was obtained.

[0076] Comparative Example 3

[0077] Comparative Example 3 changed the element of iron to copper compared with Example 1. The Cu-CTF material was injected onto the surface of the ceramic flat sheet membrane. The operation method and process parameters were the same as those of Example 1, and were as follows:

[0078] The blank ceramic flat sheet membrane was placed in anhydrous ethanol and ultrasonically cleaned for 30min, and then placed in an oven at 80°C for drying.

[0079] The CTF material was mixed with a 0.05mol / L copper chloride solution and placed on a magnetic stirrer for stirring for 1h.

[0080] Then, suction filtration, drying, centrifugal washing, and re-drying were performed to obtain the Cu-CTF composite material. Among them, 0.004mol of Cu was contained in every 50mg of CTF.

[0081] The Cu-CTF composite material was added to deionized water and ultrasonically mixed for 30min to obtain a Cu-CTF composite material aqueous solution with a concentration of 0.8g / L.

[0082] The dried ceramic flat sheet membrane was placed in a suction filtration device, and the Cu-CTF composite material aqueous solution was injected onto the surface of the ceramic flat sheet membrane using a syringe (when the Cu-CTF composite material aqueous solution was injected onto the surface of the ceramic flat sheet membrane, multiple small injections were performed to avoid material loss due to a too low suction filtration speed, and the injection times were 2-5 times). Suction filtration was performed at a pressure of -0.1Mpa until the Cu-CTF composite material was uniformly deposited on the membrane.

[0083] The sample after suction filtration was placed in an oven at 80°C for 12h, and then calcined in a tube furnace for 2h, with a calcination temperature of 500°C and a heating rate of 5°C / min. After natural cooling to room temperature, the photocatalytic ceramic flat sheet membrane loaded with Mn-CTF was obtained.

[0084] Comparative Example 4

[0085] Comparative Example 4 changed the calcination temperature compared with Example 1. The operation method and process parameters were the same as those of Example 1, and were as follows:

[0086] The blank ceramic flat sheet membrane was placed in anhydrous ethanol and ultrasonically cleaned for 30min, and then placed in an oven at 80°C for drying.

[0087] The CTF material is mixed with 0.05 mol / L ferric chloride solution and placed on a magnetic stirrer for stirring for 1 h;

[0088] Then, suction filtration, drying, centrifugal washing, and drying again are performed to obtain the Fe-CTF composite material; wherein, 0.004 mol of Fe is contained in 50 mg of the CTF.

[0089] The Fe-CTF composite material is added to deionized water, and ultrasonic mixing is performed for 30 min to obtain a water solution of the Fe-CTF composite material with a concentration of 0.8 g / L.

[0090] The dried ceramic flat sheet membrane is placed in a suction filtration device, and the water solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat sheet membrane by using a syringe (when the water solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat sheet membrane, the injection is performed in multiple small amounts to avoid material loss due to a too low suction filtration speed, and the injection is performed 2-5 times), and suction filtration is performed under a pressure of -0.1 MPa until the Fe-CTF composite material is uniformly deposited on the membrane.

[0091] The suction-filtered sample is placed in an 80℃ oven for drying for 12 h, and then placed in a tube furnace for calcination for 2 h, the calcination temperature is 200℃, and the temperature rising rate is 5℃ / min, and the Fe-CTF loaded photocatalytic ceramic flat sheet membrane is obtained after natural cooling to room temperature.

[0092] Comparative Example 5

[0093] Comparative Example 5 changes the calcination time compared with Example 1, and the operation method and process parameters are the same as those of Example 1, and are as follows:

[0094] The blank ceramic flat sheet membrane is placed in anhydrous ethanol, ultrasonic cleaning is performed for 30 min, and then placed in an 80℃ oven for drying, and standby.

[0095] The CTF material is mixed with 0.05 mol / L ferric chloride solution and placed on a magnetic stirrer for stirring for 1 h;

[0096] Then, suction filtration, drying, centrifugal washing, and drying again are performed to obtain the Fe-CTF composite material; wherein, 0.004 mol of Fe is contained in 50 mg of the CTF.

[0097] The Fe-CTF composite material is added to deionized water, and ultrasonic mixing is performed for 30 min to obtain a water solution of the Fe-CTF composite material with a concentration of 0.8 g / L.

[0098] The dried ceramic flat sheet membrane is placed in a suction filtration device, and the aqueous solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat sheet membrane using a syringe (when the aqueous solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat sheet membrane, the injection is performed multiple times in small amounts to avoid material loss due to a too low suction filtration speed, and the injection is performed 2-5 times), and suction filtration is performed at a pressure of -0.1 MPa until the Fe-CTF composite material is uniformly deposited on the membrane.

[0099] The suction-filtered sample is placed in an 80°C oven for 12 h, and then placed in a tube furnace for calcination for 0.5 h at a calcination temperature of 500°C and a temperature increase rate of 5°C / min, and then naturally cooled to room temperature to obtain the photocatalytic ceramic flat sheet membrane loaded with Fe-CTF.

[0100] Comparative Example 6

[0101] Comparative Example 6 does not perform calcination compared with Example 1, and the specific process is as follows:

[0102] The blank ceramic flat sheet membrane is placed in anhydrous ethanol, ultrasonically cleaned for 30 min, and then placed in an 80°C oven for drying, and then used.

[0103] The CTF material is mixed with a 0.05 mol / L iron chloride solution, and then placed on a magnetic stirrer for stirring for 1 h.

[0104] Then, suction filtration, drying, centrifugal washing, and re-drying are performed to obtain the Fe-CTF composite material; wherein, in every 50 mg of CTF, 0.004 mol of Fe is contained.

[0105] The Fe-CTF composite material is added to deionized water, and ultrasonically mixed for 30 min to obtain an aqueous solution of the Fe-CTF composite material with a concentration of 0.8 g / L.

[0106] The dried ceramic flat sheet membrane is placed in a suction filtration device, and the aqueous solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat sheet membrane using a syringe (when the aqueous solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat sheet membrane, the injection is performed multiple times in small amounts to avoid material loss due to a too low suction filtration speed, and the injection is performed 2-5 times), and suction filtration is performed at a pressure of -0.1 MPa until the Fe-CTF composite material is uniformly deposited on the membrane, to obtain the photocatalytic ceramic flat sheet membrane loaded with Fe-CTF.

[0107] Comparative Example 7

[0108] Comparative Example 7 changes the composite content of iron compared with Example 1, and the operation method and process parameters are the same as those of Example 1, and the specific process is as follows:

[0109] The blank ceramic flat sheet membrane is placed in anhydrous ethanol, ultrasonically cleaned for 30 min, and then placed in an 80°C oven for drying, and then used.

[0110] The CTF material was mixed with a 0.05 mol / L ferric chloride solution and placed on a magnetic stirrer for stirring for 1 h;

[0111] Then, suction filtration, drying, centrifugal washing, and drying again were performed to obtain the Fe-CTF composite material; wherein, 0.002 mol of Fe was contained in 50 mg of the CTF.

[0112] The Fe-CTF composite material was added to deionized water, and ultrasonic mixing was performed for 30 min to obtain a water solution of the Fe-CTF composite material with a concentration of 0.8 g / L.

[0113] The dried ceramic flat sheet membrane was placed in a suction filtration device, and the water solution of the Fe-CTF composite material was injected onto the surface of the ceramic flat sheet membrane by using a syringe (when the water solution of the Fe-CTF composite material was injected onto the surface of the ceramic flat sheet membrane, the injection was performed in multiple small amounts to avoid material loss due to a too low suction filtration speed, and the injection was performed 2-5 times), and suction filtration was performed under a pressure of -0.1 MPa until the Fe-CTF composite material was uniformly deposited on the membrane.

[0114] The suction-filtered sample was placed in an 80℃ oven for drying for 12 h, and then was placed in a tube furnace for calcination for 2 h, the calcination temperature was 500℃, and the temperature rising rate was 5℃ / min, and then the sample was naturally cooled to room temperature to obtain the photocatalytic ceramic flat sheet membrane loaded with Fe-CTF.

[0115] Comparative Example 8

[0116] Comparative Example 8 changed the composite content of iron compared with Example 1, and the operation method and process parameters were the same as those of Example 1, and were as follows:

[0117] The blank ceramic flat sheet membrane was placed in anhydrous ethanol, and ultrasonic cleaning was performed for 30 min, and then was placed in an 80℃ oven for drying, and was ready for use.

[0118] The CTF material was mixed with a 0.05 mol / L ferric chloride solution and placed on a magnetic stirrer for stirring for 1 h;

[0119] Then, suction filtration, drying, centrifugal washing, and drying again were performed to obtain the Fe-CTF composite material; wherein, 0.002 mol of Fe was contained in 50 mg of the CTF.

[0120] The Fe-CTF composite material was added to deionized water, and ultrasonic mixing was performed for 30 min to obtain a water solution of the Fe-CTF composite material with a concentration of 0.8 g / L.

[0121] The dried ceramic flat membrane is placed in a filtration device, and the aqueous solution of the Fe-CTF composite material is injected onto the surface of the ceramic flat membrane with a syringe (when injecting the aqueous solution of the Fe-CTF composite material into the surface of the ceramic flat membrane, multiple small injections are performed to avoid material loss due to too low a filtration speed. The number of injections is 2-5 times). Filtration is performed at a pressure of -0.1 MPa until the Fe-CTF composite material is evenly deposited on the membrane.

[0122] The filtered sample was placed in an oven at 80°C for 12 hours, and then placed in a tube furnace for calcination for 2 hours at a calcination temperature of 500°C and a heating rate of 5°C / min. After naturally cooling to room temperature, a photocatalytic ceramic flat film loaded with Fe-CTF was obtained.

[0123] test

[0124] The ceramic flat membranes loaded with materials prepared in Examples 1-3 and Comparative Examples 1-8 were subjected to photocatalytic degradation experiments and the shedding rates after use were recorded. The test results are shown in Table 1.

[0125] The photocatalytic degradation experiment used a rhodamine B (RhB) solution as the target pollutant. The specific experimental steps were as follows: Each prepared photocatalytic ceramic flat membrane was placed in 50 mL of a 50 mg / L pollutant solution and stirred to ensure full contact between the pollutant and the catalyst. After 30 minutes of dark adsorption, degradation was performed under xenon lamp irradiation for 1 hour. Three mL of the pollutant solution was removed at regular intervals and UV absorption spectroscopy was used to analyze the degradation effect. After the photocatalytic experiment, the pollutant solution was filtered and the CTF shedding rate was analyzed.

[0126] Table 1

[0127] / Degradation rate (%) CTF shedding rate (%) Example 1 98.5 1.8 Example 2 97.2 1.5 Example 3 98.1 1.9 Comparative Example 1 59.3 6.5 Comparative Example 2 68.1 5.6 Comparative Example 3 68.6 5.2 Comparative Example 4 94.5 12.5 Comparative Example 5 95.3 13.2 Comparative Example 6 93.2 85.5 Comparative Example 7 82.8 4.2 Comparative Example 8 6.5 5.0

[0128] The present application provides a method for preparing a photocatalytic ceramic flat membrane loaded with Fe-CTF, and the products and applications thereof. The preparation method comprises injecting an aqueous solution of the Fe-CTF composite material onto the surface of a blank ceramic flat membrane, vacuum filtration, drying, and high-temperature calcination, so that the Fe-CTF composite material can be uniformly and efficiently loaded onto the ceramic flat membrane. The present application achieves a high bonding strength between the CTF material and the ceramic flat membrane by compounding iron with CTF and specifically adjusting the calcination temperature and time, making it difficult to fall off during operation. This allows the ceramic flat membrane to exert its excellent filtration performance, as well as the degradation performance of CTF on organic pollutants, achieving unexpected results.

[0129] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a Fe-CTF-loaded photocatalytic ceramic flat membrane, characterized in that: The following steps are involved: Step 1: Place the blank ceramic flat membrane into the filtration device; Step 2: Under vacuum filtration, inject the aqueous solution of Fe-CTF composite material onto the surface of the ceramic flat membrane; Step 3: performing a first drying and calcining treatment on the ceramic flat membrane obtained in step 2 to obtain a Fe-CTF-loaded photocatalytic ceramic flat membrane; The calcination temperature is not less than 400° C., and the calcination time is not less than 1 hour.

2. The method for preparing a Fe-CTF-loaded photocatalytic ceramic flat membrane according to claim 1, characterized in that: In the step 2, the aqueous solution of the Fe-CTF composite material is a mixed solution of the Fe-CTF composite material and water, and the concentration is 0.5-1 g / L.

3. The method for preparing a Fe-CTF-loaded photocatalytic ceramic flat membrane according to claim 2, characterized in that: The Fe-CTF composite material was prepared by the following method: S1, mixing CTF material with iron salt solution and stirring; S2. The solution obtained in S1 is sequentially subjected to suction filtration, a second drying, centrifugal washing, and a third drying treatment to obtain a Fe-CTF composite material.

4. The method for preparing a Fe-CTF-loaded photocatalytic ceramic flat membrane according to claim 1, characterized in that: The aqueous solution of the Fe-CTF composite material contains 0.0025 to 0.005 mol of Fe per 50 to 60 mg of CTF.

5. The method for preparing a Fe-CTF-loaded photocatalytic ceramic flat membrane according to claim 4, characterized in that: The aqueous solution of the Fe-CTF composite material contains 0.003 to 0.005 mol of Fe per 50 to 60 mg of CTF.

6. The method for preparing a Fe-CTF-loaded photocatalytic ceramic flat membrane according to any one of claims 1 to 5, characterized in that: In step 3, the calcination temperature is 400°C to 600°C.

7. The method for preparing a Fe-CTF-loaded photocatalytic ceramic flat membrane according to claim 6, characterized in that: In step 3, the calcination time is 1 to 2 hours.

8. A photocatalytic ceramic flat membrane product loaded with Fe-CTF prepared by the preparation method according to any one of claims 1 to 7.

9. The Fe-CTF-loaded photocatalytic ceramic flat membrane product according to claim 8, characterized in that: Specifically, the Fe-CTF composite material is uniformly attached to the surface of the ceramic flat membrane, and the thickness of the Fe-CTF composite material is 0.1 to 0.3 mm.

10. Use of the Fe-CTF loaded photocatalytic ceramic flat membrane product as described in 8 or 9 in photocatalytic degradation of pollutants.

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