Ceramic membrane surface grafting modification experimental apparatus and method

Abstract

The present application relates to the technical field of ceramic membrane processing, in particular to a ceramic membrane surface grafting modification experiment equipment and method, which comprises a cleaning unit and a drying unit, the cleaning unit comprises a cleaning box, the inside of the cleaning box is divided into an ultrasonic cleaning area, an ethanol cleaning area and a pure water cleaning area by two partitions, a plurality of ultrasonic transducers are arranged on the bottom of the ultrasonic cleaning area, and a rack for spacing and arranging sample pieces is arranged in the ultrasonic cleaning area above the ultrasonic transducers; the experiment equipment disclosed by the present application simultaneously realizes drying and heating treatment of multiple sample pieces by using a drying circulating rack, meets the demand of orthogonal experiment of ceramic membrane hydrophobic modification design, shortens the time of pre-treatment of multiple ceramic membrane sample pieces, and all the ceramic membrane sample pieces are in a rotating operation state, so that the drying and heating degree of the ceramic membrane sample pieces is effectively guaranteed to be consistent, and the result accuracy of subsequent grafting modification experiment on the ceramic membrane surface is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of ceramic membrane treatment technology, specifically to an experimental device and method for grafting modification of ceramic membrane surfaces. Background Technology

[0002] Ceramic membranes are recognized as membrane materials with excellent structure, high chemical stability, and high thermal stability, and are widely used in membrane separation processes such as microfiltration and ultrafiltration. However, due to their inherent hydrophilic properties, they cannot be used in membrane distillation processes and require hydrophobic modification. Currently, there are many experimental methods for hydrophobic modification of ceramic membrane surfaces, but they all require using flat ceramic membranes as raw materials, cutting them to a set size, effectively cleaning them, drying them after cleaning, and then subjecting them to high-temperature insulation treatment for a period of time to maintain the high activity of the ceramic membrane surface layer.

[0003] For example, invention patent application number 2016104067565 discloses a method for preparing a superhydrophobic ceramic membrane material. This method includes the following steps: treating a porous ceramic membrane in an ultrasonic cleaner for 10-120 minutes, then drying it in an oven at 50-80°C for 1-12 hours; uniformly spreading polytetrafluoroethylene powder on the surface of the porous ceramic membrane described in step 1, ensuring complete coverage; and placing the sample described in step 2 into a high-temperature furnace, treating it at 300-700°C for 1-12 hours under a nitrogen atmosphere to obtain a superhydrophobic ceramic membrane material. In the experimental testing phase of this invention patent's method for preparing the superhydrophobic ceramic membrane material, orthogonal experiments are often designed to investigate the influence of various experimental parameters on the hydrophobic properties of the prepared ceramic membrane, thereby determining the optimal parameter values ​​for the hydrophobic modification of the ceramic membrane. Then, in the experiment of hydrophobic modification of ceramic membranes, the pre-treatment process is time-consuming, requiring a large number of experimental samples for cleaning, drying, and prolonged heating. Existing ceramic membrane pre-treatment equipment cannot simultaneously process a large number of ceramic membrane samples. For example, utility model patent application number 2016209038174 discloses an ultrasonic cleaning device for ceramic membranes, including a cleaning tank, inlet, blower, drying zone, outlet, cleaning tank wall, vibrating steel plate, ultrasonic transducer, and drain outlet; the upper part of the ultrasonic cleaning device for ceramic membranes is arranged from left to right as the outlet, drying zone, blower, and cleaning tank. Although the cleaning device disclosed in this utility model achieves efficient, streamlined processing of ceramic membrane samples, the limited length of the drying zone prevents simultaneous drying and heating of multiple ceramic membrane samples, thus severely restricting the entire experimental process of hydrophobic modification of ceramic membranes. Based on this, this application proposes an experimental device for ceramic membrane surface grafting modification and a method for using this experimental device that can effectively solve the above-mentioned technical problems. Summary of the Invention

[0004] The purpose of this invention is to provide an experimental device and method for grafting modification of ceramic membrane surfaces, so as to overcome the shortcomings of existing experimental devices that limit the hydrophobic modification of ceramic membranes.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] An experimental device for grafting modification of ceramic film surface includes a cleaning unit and a drying unit. The cleaning unit includes a cleaning box. The interior of the cleaning box is divided into an ultrasonic cleaning zone, an ethanol cleaning zone and a pure water cleaning zone by two partitions. Several ultrasonic transducers are arranged on the bottom of the ultrasonic cleaning zone. A shelf for placing sample pieces at intervals is arranged in the ultrasonic cleaning zone above the ultrasonic transducers.

[0007] The drying unit includes a drying chamber. A feeding door is provided on the side of the drying chamber near the cleaning unit, and a discharging door is provided on the side of the drying chamber away from the cleaning unit. A heating device is provided inside the drying chamber. A base extending towards the cleaning unit is provided at the lower end of the drying chamber. Two parallel tracks are provided on the upper surface of the base. A drying circulation rack is movably arranged between the two tracks. A drive device is provided inside the drying chamber to enable the drying circulation rack to move along the tracks.

[0008] A material-grabbing and conveying unit is located directly above the opening of the cleaning box. The sample pieces on the shelf are picked up one by one by the material-grabbing and conveying unit and sequentially inserted into the ethanol cleaning zone and the pure water cleaning zone before being placed on the drying circulation rack.

[0009] As a further feature of the above scheme, the drying circulating material rack includes two side frames respectively set on corresponding tracks. The lower end of the side frame is provided with a row of traveling wheels that match the tracks. Each side frame has a drive wheel rotatably set at both the upper and lower ends. A closed-loop conveyor is provided between the upper and lower drive wheels. A rotating shaft is provided between the aligned drive wheels on the two side frames. A circulating motor connected to the rotating shaft is provided on one of the side frames. Multiple sample holders are arranged horizontally at equal intervals between the two closed-loop conveyors.

[0010] As a further feature of the above scheme, the sample holder includes a shovel frame, the lower end of which is provided with a number of support rods at intervals, and both the front and rear ends of the shovel frame are connected to booms. The upper ends of the two booms are rotatably connected to a rotating rod, and the outer surfaces of the two closed-loop conveyors are provided with connectors that are rotatably connected to the rotating rods.

[0011] As a further provision of the above scheme, the transmission wheel is either a pulley or a sprocket, and the closed-loop conveyor is either a conveyor belt or a chain.

[0012] As a further provision of the above scheme, the driving device includes two parallel transmission chain assemblies arranged at the front and rear, and a drive motor for driving the transmission chain assemblies is provided on the outer side of the drying box. A connecting block is provided between the transmission chain assemblies and the drying circulation rack.

[0013] As a further provision of the above solution, the material handling and conveying unit includes a support frame fixed on the cleaning tank. The upper end of the support frame has roller grooves aligned with each other on both the front and rear sides. A movable plate is arranged between the two roller grooves. The front and rear ends of the movable plate are each provided with a row of rollers that match the roller grooves. The upper end of the support frame is provided with a walking drive assembly that enables the movable plate to move at a set distance. A telescopic device is installed on the movable plate. The lower end of the telescopic device is connected to a gripping mechanism for gripping the sample.

[0014] As a further provision of the above solution, the walking drive assembly includes a lead screw and a slide rod arranged parallel to each other. One end of the lead screw is connected to a lead screw motor, and the moving plate is provided with a nut block threadedly connected to the lead screw and a guide slider connected to the slide rod.

[0015] As a further feature of the above solution, the gripping mechanism includes a lifting plate, with clamping plates rotatably connected to both sides of the lower end of the lifting plate, and a drive cylinder is provided on the lifting plate to make the two clamping plates move closer together or open.

[0016] As a further provision of the above scheme, the lower end of the telescopic device is connected to a fixed plate, the upper end of the lifting plate is fixedly provided with a positioning shaft, and the positioning shaft is rotatably connected to the fixed plate. One end of the positioning shaft is provided with a meshing gear, and a horizontal rack is provided on the support frame near the drying unit. The horizontal rack and the meshing gear are arranged on the same straight line.

[0017] The present invention also discloses a method for grafting modification of ceramic film surface using the above-mentioned experimental equipment, comprising the following steps:

[0018] 1) Take flat ceramic membrane as raw material and divide it into multiple ceramic membrane sample pieces of the same area according to size requirements;

[0019] 2) Arrange multiple ceramic membrane samples at intervals on the shelf in the experimental equipment, and then ultrasonically clean them for 5-20 minutes. After ultrasonic cleaning, use the material grabbing and conveying unit to grab the ceramic membrane samples one by one and insert them into the ethanol cleaning area and the pure water cleaning area in sequence for cleaning. After cleaning, place them on the drying circulating material rack.

[0020] 3) After all the ceramic film samples are placed one by one on the drying circulation rack, they are sent into the drying box so that they are dried and heated by the heating device during the circulation process.

[0021] 4) Prepare chlorosilane modification solutions of various concentrations, and then put the dried and heated ceramic membrane samples into the corresponding chlorosilane modification solutions, mark them, and react for 24 hours;

[0022] 5) Clean the ceramic film sample after step 4 with anhydrous ethanol and dry it. Repeat this process 3 times. Then rinse it with pure water until the surface solvent is completely cleaned. Place the ceramic film sample in an oven for heat treatment for 10-30 hours and let it cool naturally to room temperature.

[0023] 6) Finally, the multiple ceramic membrane samples obtained in step 5 are sequentially tested and characterized as modified membranes, tested for membrane distillation performance, and tested for acid and alkali resistance and chemical solvent resistance, so as to obtain the optimal experimental parameter values.

[0024] Beneficial effects:

[0025] 1. The experimental equipment disclosed in this invention is designed for the hydrophobic modification experiment of ceramic membrane surface. The experimental equipment can perform ultrasonic cleaning, ethanol cleaning and pure water cleaning on multiple ceramic membrane samples in sequence at one time. After cleaning, multiple ceramic membrane samples can be placed one by one on the drying circulation rack. Then, the drying circulation rack can be used to simultaneously dry and heat the multiple samples, which meets the requirements of orthogonal experiment for hydrophobic modification design of ceramic membrane and shortens the pretreatment time of multiple ceramic membrane samples.

[0026] 2. The design of the cleaning unit in the experimental equipment disclosed in this invention enables the ceramic membrane sample to be thoroughly cleaned, ensuring that the surface of the cleaned ceramic membrane sample has more hydroxyl groups, which facilitates subsequent grafting modification. In addition, the cleaned ceramic membrane sample is placed on a circulating drying rack. When the ceramic membrane sample is dried and heated in the drying chamber, all the ceramic membrane sample is in a state of continuous rotation, which effectively ensures that the drying and heating degree of the ceramic membrane sample is consistent, and there is no error in any experimental parameters. This ensures the accuracy of the results when the ceramic membrane surface is grafted and modified in the subsequent experiment, and guarantees the overall experimental effect.

[0027] 3. The experimental equipment in this invention, through the structural design of the material handling and conveying unit, can automatically handle ceramic membrane samples during the cleaning process, automatically feed them into ethanol or aqueous solution for cleaning, and after cleaning, place the handled ceramic membrane samples one by one onto the sample holder on the drying and circulating material rack; the whole process does not require manual operation, realizing the automation of the entire pretreatment process of ceramic membrane samples, and the effect is excellent. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a first-angle three-dimensional structural diagram of the experimental equipment of the present invention;

[0030] Figure 2 This is a two-dimensional structural diagram of the experimental equipment of the present invention from a second angle;

[0031] Figure 3 This is a schematic diagram of the internal planar structure of the cleaning tank in the experimental equipment of this invention;

[0032] Figure 4 This is a schematic diagram of the three-dimensional structure of the drying oven, drying circulation rack, etc. in the experimental equipment of this invention;

[0033] Figure 5 This is a schematic diagram of the internal planar structure of the drying oven in the experimental equipment of this invention;

[0034] Figure 6 This is a three-dimensional structural diagram of the drying circulating material rack in the experimental equipment of the present invention;

[0035] Figure 7 This is a three-dimensional structural diagram of the sample holder in the experimental equipment of the present invention;

[0036] Figure 8 This is a three-dimensional structural diagram of the support frame, walking drive assembly, etc. in the experimental equipment of the present invention;

[0037] Figure 9 This is a schematic diagram of the three-dimensional structure of the gripping mechanism and other components in the experimental equipment of this invention.

[0038] in:

[0039] 1-Cleaning box, 100-Partition, 101-Ultrasonic cleaning area, 102-Ethanol cleaning area, 103-Pure water cleaning area, 104-Ultrasonic transducer, 105-Shelf;

[0040] 2-Drying oven, 201-Feeding box door, 202-Removing box door, 203-Heating device, 204-Base, 205-Rail, 206-Drive device, 2061-Transmission chain assembly, 2062-Drive motor, 2063-Connecting block;

[0041] 3-Drying circulating material rack, 301-Side frame, 302-Walking wheel, 303-Drive wheel, 304-Closed-loop conveyor, 305-Rotating shaft, 306-Circulating motor, 307-Sample piece holder, 3071-Shovel frame, 3072-Support rod, 3073-Hanging arm, 3074-Rotating rod, 308-Connecting part;

[0042] 4-Material handling and conveying unit, 401-Support frame, 402-Roller groove, 403-Moving plate, 404-Roller, 405-Walking drive assembly, 406-Telescopic device, 407-Gripping mechanism, 408-Nut block, 409-Guide slider, 410-Fixed plate, 411-Horizontal rack;

[0043] 4051-Lead screw, 4052-Lead screw motor, 4071-Lifting plate, 4072-Clamping plate, 4073-Positioning shaft, 4074-Meshing gear. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The following will refer to the appendix... Figure 1-9 This application will be described in detail with reference to the embodiments.

[0046] Example 1

[0047] Example 1 discloses an experimental apparatus for grafting modification of ceramic film surfaces, as shown in the attached figure. Figure 1 and attached Figure 2 The main body of the experimental equipment includes a cleaning unit and a drying unit. First, the ceramic membrane sample is cleaned by the cleaning unit. After cleaning, it is sent to the drying unit for drying and is kept in a high-temperature environment for a period of time for processing.

[0048] Reference Appendix Figure 1 and attached Figure 3The cleaning unit includes a cleaning chamber 1, inside which two partitions 100 divide the interior into an ultrasonic cleaning zone 101, an ethanol cleaning zone 102, and a pure water cleaning zone 103. Several ultrasonic transducers 104 are installed at the bottom of the ultrasonic cleaning zone 101. A shelf 105 is installed above the ultrasonic transducers 104 within the ultrasonic cleaning zone 101, through which multiple ceramic membrane samples are arranged at intervals. During the cleaning process, multiple ceramic membrane samples are first placed at intervals on the shelf 105 and ultrasonically cleaned for a period of time using the ultrasonic transducers 104. Then, the ultrasonically cleaned ceramic membrane samples are sequentially immersed in the ethanol cleaning zone 102 and the pure water cleaning zone 103, and rinsed with ethanol and pure water respectively, ensuring that the surface of the cleaned ceramic membrane samples has more hydroxyl groups, facilitating subsequent grafting modification.

[0049] Reference Appendix Figure 4 Appendix Figure 5 and attached Figure 6 The drying unit includes a drying chamber 2, with a loading door 201 on the side of the drying chamber 2 near the cleaning unit and a unloading door 202 on the side away from the cleaning unit. Two heating devices 203 are installed inside the drying chamber 2, one on each of the front and rear inner walls. A base 204 extending towards the cleaning unit is located at the lower end of the drying chamber 2. Two parallel tracks 205 are provided on the upper surface of the base 204, and a drying circulation rack 3 is movably positioned between the two tracks 205.

[0050] The specific drying circulating material rack 3 includes two side frames 301 respectively set on corresponding tracks 205. A row of traveling wheels 302 matching the tracks 205 is provided at the lower end of each side frame 301. A drive wheel 303 is rotatably mounted at both the upper and lower ends of each side frame 301, and a closed-loop conveyor 304 is provided between the two drive wheels 303. The drive wheel 303 is either a pulley or a sprocket, and the closed-loop conveyor 304 is either a conveyor belt or a chain. A rotating shaft 305 is provided between the aligned drive wheels 303 on the two side frames 301, and a circulating motor 306 connected to the rotating shaft 305 is mounted on one of the side frames 301. Multiple horizontally positioned sample holders 307 are then evenly spaced between the two closed-loop conveyors 304.

[0051] Reference Appendix Figure 6 and attached Figure 7The sample holder 307 includes a shovel frame 3071, with several support rods 3072 spaced apart at the lower end of the shovel frame 3071. Both the front and rear ends of the shovel frame 3071 are connected to lifting arms 3073. The upper ends of the two lifting arms 3073 are rotatably connected to a rotating rod 3074. The outer surfaces of the two closed-loop conveying components 304 are each provided with a connecting piece 308 rotatably connected to the rotating rod 3074. Through the above structural design of the sample holder 307, when the cleaned ceramic film sample is placed on the sample holder 307 and transported by the closed-loop conveying component 304, the entire sample holder 307 can always remain horizontal, ensuring the stability of the transport of the placed ceramic film sample.

[0052] In addition, a drive device 206 is installed inside the drying chamber 2 to move the drying circulation rack 3 along the track 205. Specifically, the drive device 206 includes two parallel transmission chain assemblies 2061, and a drive motor 2062 for driving the transmission chain assemblies 2061 is installed on the outer side of the drying chamber 2. A connecting block 2063 is provided between the transmission chain assemblies 2061 and the drying circulation rack 3. The drive device 206 uses the drive motor 2062 as a power source to realize the forward or reverse transmission of the transmission chain assemblies 2061, and then the connecting block 2063 enables the entire drying circulation rack 3 to move along the track 205.

[0053] Reference Appendix Figure 1 Appendix Figure 8 and attached Figure 9 A material-grabbing and conveying unit 4 is located directly above the opening of the cleaning tank 1, so that the sample pieces on the shelf 105 are picked up one by one by the material-grabbing and conveying unit 4 and sequentially inserted into the ethanol cleaning zone 102 and the pure water cleaning zone 103 before being placed on the drying circulating material rack 3. Specifically, the material-grabbing and conveying unit 4 includes a support frame 401 fixed on the cleaning tank 1. The support frame 401 has roller grooves 402 aligned with each other on both the front and rear sides of its upper end. Then, a moving plate 403 is arranged between the two roller grooves 402. The front and rear ends of the moving plate 403 are provided with a row of rollers 404 that match the roller grooves 402. Additionally, a travel drive assembly 405 is provided at the upper end of the support frame 401 to enable the movable plate 403 to move at a set distance. Specifically, the travel drive assembly 405 includes a lead screw 4051 and a slide rod arranged parallel to each other. One end of the lead screw 4051 is connected to a lead screw motor 4052. The movable plate 403 is provided with a nut block 408 threadedly connected to the lead screw 4051 and a guide slider 409 connected to the slide rod. By controlling the rotation direction and number of rotations of the lead screw motor 4052, the movable plate 403 can move to any position along the direction of the roller groove 402 at the upper end of the support frame 401.

[0054] A telescopic device 406 is installed on the movable plate 403. This telescopic device 406 can be either a cylinder or an electric telescopic rod. A gripping mechanism 407 for gripping the sample is connected to the lower end of the telescopic device 406. Specifically, the gripping mechanism 407 includes a lifting plate 4071. Clamping plates 4072 are rotatably connected to both sides of the lower end of the lifting plate 4071. The lifting plate 4071 is equipped with a drive cylinder (not shown in the figure) to make the two clamping plates 4072 move closer together or open.

[0055] Finally, to enable the gripping mechanism 407 to horizontally place the gripped ceramic film samples one by one onto the sample holder 307 in the drying circulating material rack 3, a fixed plate 410 is connected to the lower end of the telescopic device 406, and a positioning shaft 4073 is fixedly installed at the upper end of the lifting plate 4071, and the positioning shaft 4073 is rotatably connected to the fixed plate 410. A meshing gear 4074 is provided at one end of the positioning shaft 4073, and a horizontal rack 411 is provided on the support frame 401 near the drying unit, with the horizontal rack 411 and the meshing gear 4074 arranged on the same straight line. After the gripping mechanism 407 grips the vertically placed ceramic film sample, as it moves toward the drying circulating material rack 3, the positioning shaft 4073 rotates through the meshing transmission between the meshing gear 4074 and the horizontal rack 411. Then, the positioning shaft 4073 drives the entire gripping mechanism 407 and the ceramic film sample to rotate from a vertical state to a horizontal state until the ceramic film sample moves above the sample holder 307. Then, the clamping force is released, so that the cleaned ceramic film sample can be placed one by one in the sample holder 307.

[0056] Example 2

[0057] Example 2 discloses a method for grafting modification of ceramic film surfaces using the experimental equipment designed in Example 1. The method includes the following steps:

[0058] S1: Take flat ceramic membrane as raw material and divide it into multiple ceramic membrane sample pieces of 15cm*15cm size according to the size requirements;

[0059] S2: Arrange multiple ceramic membrane samples at intervals on the shelf in the experimental equipment, and then ultrasonically clean them for 10 minutes. After ultrasonic cleaning, use the material handling and conveying unit to pick up the ceramic membrane samples one by one and put them into the ethanol cleaning area and the pure water cleaning area in sequence for cleaning. Specifically, during the cleaning process, the picked ceramic membrane samples are immersed in the ethanol cleaning area and the pure water cleaning area for 30 seconds. The immersion in each cleaning area is repeated 3 times. After cleaning, they are placed on the drying circulating material rack one by one.

[0060] S3: After all the ceramic film samples are placed one by one on the drying circulation rack, they are sent into the drying box so that they are dried and heated by the heating device during the circulation process. The heating device keeps the internal temperature of the drying box at 85±5℃.

[0061] S4: Prepare chlorosilane modification solutions with concentrations of 0.01 mol / L, 0.05 mol / L, 0.1 mol / L, 0.15 mol / L, and 0.2 mol / L. The specific chlorosilane modification solutions are prepared by dissolving methyltrichlorosilane in anhydrous ethanol and stirring until homogeneous. Then, place the dried and heated ceramic membrane samples into the corresponding chlorosilane modification solutions, mark them, and react for 16 hours.

[0062] S5: Clean the ceramic film sample after step 4 with anhydrous ethanol and dry it. Repeat this process 3 times. Then rinse with pure water until the surface solvent is completely cleaned. Place the ceramic film sample in an oven and heat treat it at 75±2℃ for 18 hours. Let it cool naturally to room temperature.

[0063] S6: The multiple ceramic membrane samples obtained in step 5 are sequentially subjected to tests and characterization of the modified membrane, membrane distillation performance tests, and acid and alkali resistance and chemical solvent resistance tests to obtain the optimal experimental parameter values.

[0064] Example 3

[0065] Example 3 discloses a method for grafting modification of ceramic film surfaces using the experimental equipment designed in Example 1. The method includes the following steps:

[0066] S1: Take flat ceramic membrane as raw material and divide it into multiple ceramic membrane sample pieces of 15cm*15cm size according to the size requirements;

[0067] S2: Arrange multiple ceramic membrane samples at intervals on the shelf in the experimental equipment, and then ultrasonically clean them for 10 minutes. After ultrasonic cleaning, use the material handling and conveying unit to pick up the ceramic membrane samples one by one and put them into the ethanol cleaning area and the pure water cleaning area in sequence for cleaning. Specifically, during the cleaning process, the picked ceramic membrane samples are immersed in the ethanol cleaning area and the pure water cleaning area for 30 seconds. The immersion in each cleaning area is repeated 3 times. After cleaning, they are placed on the drying circulating material rack one by one.

[0068] S3: After all the ceramic film samples are placed one by one on the drying circulation rack, they are sent into the drying box so that they are dried and heated by the heating device during the circulation process. The heating device keeps the internal temperature of the drying box at 85±5℃.

[0069] S4: Prepare chlorosilane modification solutions with concentrations of 0.01 mol / L, 0.05 mol / L, 0.1 mol / L, 0.15 mol / L, and 0.2 mol / L. Specifically, the chlorosilane modification solutions are prepared by dissolving trimethylchlorosilane in anhydrous ethanol and stirring until homogeneous. Then, place the dried and heated ceramic membrane samples into the corresponding chlorosilane modification solutions, mark them, and react for 24 hours.

[0070] S5: Clean the ceramic film sample after step 4 with anhydrous ethanol and dry it. Repeat this process 3 times. Then rinse with pure water until the surface solvent is completely cleaned. Place the ceramic film sample in an oven and heat treat it at 70±2℃ for 24 hours. Let it cool naturally to room temperature.

[0071] S6: The multiple ceramic membrane samples obtained in step 5 are sequentially subjected to tests and characterization of the modified membrane, membrane distillation performance tests, and acid and alkali resistance and chemical solvent resistance tests to obtain the optimal experimental parameter values.

[0072] Meanwhile, by comparing and analyzing multiple sets of experimental data from Examples 1 and 2 above, and using the contact angle as an evaluation index for the modified membrane, the optimal hydrophobic conditions were found to be: a modification solution concentration of 0.20 mol / L, a modification time of 24 hours, a heat treatment temperature of 70℃, and a heat treatment time of 24 hours. Throughout the experiment, the modified membrane achieved a maximum contact angle of 121.5°, and the apparent porosity of the membrane modified by graft polymerization did not change significantly, indicating good hydrophobic performance.

[0073] In addition, the test results of the modified membrane’s acid and alkali resistance and chemical solvent resistance show that the ceramic membranes prepared in Example 2 and Example 2 have good resistance to weak acids and weak alkalis and chemical solvents, but the stability of their resistance to strong acids and alkalis is still lacking.

[0074] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An experimental apparatus for grafting modification of ceramic film surfaces, characterized in that, The system includes a cleaning unit and a drying unit. The cleaning unit includes a cleaning chamber (1). The interior of the cleaning chamber (1) is divided into an ultrasonic cleaning zone (101), an ethanol cleaning zone (102), and a pure water cleaning zone (103) by two partitions (100). Several ultrasonic transducers (104) are provided on the bottom of the ultrasonic cleaning zone (101). A shelf (105) for placing sample pieces at intervals is provided in the ultrasonic cleaning zone (101) above the ultrasonic transducers (104). The drying unit includes a drying box (2), a feeding box door (201) is provided on the side of the drying box (2) near the cleaning unit, and a discharging box door (202) is provided on the side of the drying box (2) away from the cleaning unit. A heating device (203) is provided inside the drying box (2). A base (204) extending towards the cleaning unit is provided at the lower end of the drying box (2). Two parallel tracks (205) are provided on the upper surface of the base (204). A drying circulation rack (3) is movably arranged between the two tracks (205). A driving device (206) is provided inside the drying box (2) to realize the movement of the drying circulation rack (3) along the tracks (205). A material-grabbing and conveying unit (4) is provided directly above the opening of the cleaning box (1). The sample pieces on the shelf (105) are picked up one by one by the material-grabbing and conveying unit (4) and inserted into the ethanol cleaning area (102) and the pure water cleaning area (103) in sequence, and then placed on the drying circulating material rack (3). The drying circulating material rack (3) includes two side frames (301) respectively set on corresponding tracks (205). The lower end of the side frame (301) is provided with a row of traveling wheels (302) that match the track (205). Each side frame (301) has a drive wheel (303) rotatably set at both the upper and lower ends. A closed-loop conveyor (304) is set between the upper and lower drive wheels (303). A rotating shaft (305) is set between the aligned drive wheels (303) on the two side frames (301). A circulating motor (306) connected to the rotating shaft (305) is set on one of the side frames (301). Multiple sample holders (307) are set at equal intervals between the two closed-loop conveyors (304) in a horizontal state. The material handling and conveying unit (4) includes a support frame (401) fixed on the cleaning box (1). The support frame (401) has roller grooves (402) aligned with each other on both the front and rear sides of the upper end. A moving plate (403) is arranged between the two roller grooves (402). A row of rollers (404) matching the roller grooves (402) is arranged at both the front and rear ends of the moving plate (403). A walking drive assembly (405) is provided at the upper end of the support frame (401) to realize the moving plate (403) moving at a set distance. A telescopic device (406) is installed on the moving plate (403). A gripping mechanism (407) for gripping the sample is connected to the lower end of the telescopic device (406). The gripping mechanism (407) includes a lifting plate (4071), and clamping plates (4072) are rotatably connected to both sides of the lower end of the lifting plate (4071). A drive cylinder is provided on the lifting plate (4071) to realize that the two clamping plates (4072) move closer to each other or open. The lower end of the telescopic device (406) is connected to a fixed plate (410), and the upper end of the lifting plate (4071) is fixedly provided with a positioning shaft (4073), and the positioning shaft (4073) is rotatably connected to the fixed plate (410). One end of the positioning shaft (4073) is provided with a meshing gear (4074), and a horizontal rack (411) is provided on the support frame (401) near the drying unit. The horizontal rack (411) and the meshing gear (4074) are arranged on the same straight line.

2. The experimental apparatus for ceramic film surface grafting modification according to claim 1, characterized in that: The sample holder (307) includes a shovel frame (3071), and a number of support rods (3072) are spaced apart at the lower end of the shovel frame (3071). Both the front and rear ends of the shovel frame (3071) are connected to booms (3073). The upper ends of the two booms (3073) are rotatably connected to a rotating rod (3074). The outer surfaces of the two closed-loop conveyors (304) are provided with connectors (308) that are rotatably connected to the rotating rods (3074).

3. The experimental apparatus for ceramic film surface grafting modification according to claim 1, characterized in that: The transmission wheel (303) is either a pulley or a sprocket, and the closed-loop conveyor (304) is either a conveyor belt or a chain.

4. The experimental apparatus for ceramic film surface grafting modification according to claim 1, characterized in that: The drive device (206) includes two parallel transmission chain assemblies (2061), and a drive motor (2062) for driving the transmission chain assembly (2061) is provided on the outer side of the drying box (2). A connecting block (2063) is provided between the transmission chain assembly (2061) and the drying circulating material rack (3).

5. The experimental apparatus for ceramic film surface grafting modification according to claim 1, characterized in that: The walking drive assembly (405) includes a lead screw (4051) and a slide rod arranged in parallel to each other. One end of the lead screw (4051) is connected to a lead screw motor (4052). The moving plate (403) is provided with a nut block (408) threadedly connected to the lead screw (4051) and a guide slider (409) connected to the slide rod.

6. A method for surface grafting modification of ceramic films using the experimental equipment described in any one of claims 1-5, characterized in that, Includes the following steps: 1) Take flat ceramic membrane as raw material and divide it into multiple ceramic membrane sample pieces of the same area according to size requirements; 2) Arrange multiple ceramic membrane samples at intervals on the shelf in the experimental equipment, and then ultrasonically clean them for 5-20 minutes. After ultrasonic cleaning, use the material grabbing and conveying unit to grab the ceramic membrane samples one by one and insert them into the ethanol cleaning area and the pure water cleaning area in sequence for cleaning. After cleaning, place them on the drying circulating material rack. 3) After all the ceramic film samples are placed one by one on the drying circulation rack, they are sent into the drying box so that they are dried and heated by the heating device during the circulation process. 4) Prepare chlorosilane modification solutions of various concentrations, and then put the dried and heated ceramic membrane samples into the corresponding chlorosilane modification solutions, mark them, and react for 24 hours; 5) Clean the ceramic film sample after step 4 with anhydrous ethanol and dry it. Repeat this process 3 times. Then rinse it with pure water until the surface solvent is completely cleaned. Place the ceramic film sample in an oven for heat treatment for 10-30 hours and let it cool naturally to room temperature. 6) Finally, the multiple ceramic membrane samples obtained in step 5 are sequentially tested and characterized as modified membranes, tested for membrane distillation performance, and tested for acid and alkali resistance and chemical solvent resistance, so as to obtain the optimal experimental parameter values.

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