Novel plasma super-hydrophilic treatment method for PPS diaphragm

Abstract

The invention relates to the technical field of PPS diaphragm hydrophilic treatment, and discloses a novel PPS diaphragm plasma super-hydrophilic treatment method which comprises the following steps: S1, gas plasma treatment; s2, washing and blow-drying the PPS diaphragm subjected to plasma treatment, and then putting the PPS diaphragm into a P1 solution for soaking treatment; s3, washing for the first time; s4, the PPS diaphragm washed for the first time is put into a P2 solution to be soaked; s5, washing for the second time; and S6, drying. The preparation method comprises the following steps: carrying out plasma treatment on a PPS diaphragm through polar group gas such as oxygen to change the surface characteristics of PPS, soaking in an organic compound P1 solution containing a hydrophilic group, washing twice, soaking in a high-molecular polymer P2 solution containing a hydrophilic group, and finally washing twice and drying again to realize the conversion from hydrophobicity to hydrophilicity. The long-term hydrophilicity of the PPS diaphragm in the alkaline water electrolysis hydrogen production process is ensured, and the potential safety hazard of high-temperature concentrated sulfuric acid treatment in the production process and the quality stability are also solved.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrophilic treatment of PPS separator membranes, particularly to the field of alkaline water electrolysis for hydrogen production in hydrogen energy, and specifically to a novel method for plasma super-hydrophilic treatment of PPS diaphragms. Background Art

[0002] Hydrogen energy is an ideal high-efficiency and clean energy. The alkaline water electrolysis process for hydrogen production dominates the hydrogen production energy industry. In order to obtain higher-purity gas while reducing the energy consumption of the water electrolyzer, the separator material is crucial. The main functions of the separator in the alkaline water electrolysis cell for hydrogen production are: 1) isolating hydrogen and oxygen generated during the electrolysis of water; 2) allowing ions in the electrolytic bath liquid to move freely. The hydrophilicity of the separator directly affects the internal resistance of the electrolyzer.

[0003] Oxygen and hydrogen generated by the electrolysis of water are separated by the separator in the electrolyzer. Therefore, the performance of the separator directly affects the gas purity and DC power consumption in the electrolyzer. The ion permeability of the PPS separator directly affects the electrolysis efficiency of the alkaline water electrolyzer using the separator. Improving the ion permeability of the separator can reduce the surface resistance of the separator, thereby enhancing the electrolysis efficiency of the alkaline water electrolyzer.

[0004] A novel composite separator based on polyphenylene sulfide (PPS) fabric is widely used due to its excellent heat resistance, mechanical strength, and electrical properties. However, the hydrophilicity of the PPS fabric is too poor, resulting in too large an internal resistance of the electrolyzer using the PPS separator and a reduction in hydrogen production efficiency. Therefore, hydrophilic treatment of the PPS separator is required.

[0005] There are mainly three methods for hydrophilic treatment of PPS separators:

[0006] 1) One is the chemical treatment of the PPS separator: attaching hydrophilic functional groups (-SO3H, -COOH, etc.) to the molecular chain of PPS. However, these functional groups are not stable in high-temperature alkaline electrolytes.

[0007] 2) Coating a mixture of polymer and zirconia on the surface of the PPS separator to improve its hydrophilicity, forming a composite separator with a similar Sandwich structure. The use of this process must strictly control the composition and ratio of the polymer and zirconia and the coating thickness to ensure its hydrophilicity and reduce the internal resistance of the electrolyzer. At the same time, the airtightness of the PPS separator is also affected more or less. In addition, its adhesion in high-temperature alkaline electrolytes will also decrease over time, with the risk of peeling.

[0008] 3) The PPS membrane is pretreated with concentrated sulfuric acid at high temperature and then soaked in a solution with hydrophilic functional groups, which can maintain stability in high-temperature alkaline electrolytes. However, in the production process, the use of the high-temperature concentrated sulfuric acid process poses great challenges to production safety and product stability.

[0009] Therefore, we need to propose a new plasma super-hydrophilic treatment method for PPS diaphragms to ensure the long-term hydrophilicity of PPS diaphragms in the alkaline water electrolysis hydrogen production process. Summary of the Invention

[0010] The purpose of the present invention is to provide a new plasma super-hydrophilic treatment method for PPS diaphragms. The PPS diaphragm is treated by plasma with polar group gases such as oxygen to change the surface characteristics of PPS, and then soaked in the organic compound P1 solution containing hydrophilic groups such as -OH, -NH 2 , -SO 3 H. After two water washes, it is then soaked in the polymer P2 solution containing hydrophilic groups such as -OH, -NH 2 , -SO 3 H. Finally, after two more water washes and drying, the transformation from hydrophobicity to hydrophilicity is achieved, ensuring the long-term hydrophilicity of the PPS diaphragm in the alkaline water electrolysis hydrogen production process, and also solving the safety hazards and quality stability problems in the production process during the treatment with high-temperature concentrated sulfuric acid, so as to solve the problems raised in the above background technology.

[0011] To achieve the above object, the present invention provides the following technical solution: A new plasma super-hydrophilic treatment method for PPS diaphragms, comprising the following steps:

[0012] S1. Gas plasma treatment: The PPS diaphragm is treated by plasma with polar group gases to change the surface characteristics of the PPS diaphragm;

[0013] S2. After the PPS diaphragm treated by plasma is washed with water and dried, it is put into the P1 solution for soaking treatment, and the P1 solution is heated. The P1 solution is an organic compound solution;

[0014] S3. First water wash: The PPS diaphragm soaked in the P1 solution is put into a water wash tank and washed with water twice, and compressed air is introduced for stirring during the water wash process;

[0015] S4. The PPS diaphragm after the first water wash is put into the P2 solution for soaking treatment, and the P2 solution is heated. The P2 solution is an organic compound solution;

[0016] S5. Second water wash: The PPS diaphragm soaked in the P2 solution is put into a water wash tank and washed with water twice, and compressed air is introduced for stirring during the water wash process;

[0017] S6. Drying: The PPS diaphragm after the second water wash is put into a dryer for drying.

[0018] Preferably, in step S1, atmospheric plasma treatment is selected for plasma treatment. The polar group gas mainly includes oxygen. By bombarding the surface of the PPS diaphragm with ions, the surface of the PPS diaphragm is cleaned, and at the same time, the surface properties of the PPS diaphragm are changed through the chemical reaction of the polar group gas.

[0019] Preferably, when the polar group gas bombards the surface of the PPS diaphragm, the gas flow rate is 10 - 30 L / min.

[0020] Preferably, in step S2, the organic compounds in the P1 solution include: 3-aminopropyltriethoxysilane, tetraethoxysilane, tetramethoxysilane, aminopropyltrimethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-[(2,3)-epoxypropoxy]propylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, diethylenetriaminepropyltrimethoxysilane, and polyethylene diamine.

[0021] Preferably, in step S2, the heating method of the P1 solution is selected as hot water coil heating, and the heating temperature of the P1 solution is controlled at 30 - 60 °C. The soaking time of the PPS diaphragm in the P1 solution is 3 - 20 min.

[0022] Preferably, in steps 3 and 5, each water wash includes two water wash processes, and the time for each water wash process is 1 - 5 min. Both water wash processes adopt a continuous overflow design.

[0023] Preferably, during water washing, clean water is continuously replenished in the second water wash tank during the second water wash process. The clean water in the second water wash tank continuously overflows into the first water wash tank during the first water wash process, and the clean water in the first water wash tank is continuously discharged through overflow.

[0024] Preferably, air nozzles are provided at the bottoms of both the first water wash tank and the second water wash tank. One end of the air nozzle is connected to a device for discharging compressed air, and air flow enters the bottom of the PPS diaphragm through the air nozzle to form air agitation to ensure the cleaning effect on the PPS diaphragm.

[0025] Preferably, in step S4, the heating method of the P2 solution is selected as hot water coil heating, and the heating temperature of the P2 solution is controlled at 50 - 90 °C. The soaking time of the PPS diaphragm in the P2 solution is 3 - 15 min.

[0026] Preferably, in step S6, the dryer is a dryer with an exhaust system, the drying temperature is set at 95 - 102 °C, and the drying time is 0.5 - 2 h.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] The present invention subjects the PPS separator to plasma treatment with polar group gases such as oxygen to change the surface characteristics of PPS, and immerses it in an organic compound P1 solution containing hydrophilic groups such as -OH, -NH 2 , -SO 3 H. After two water washes, it is then immersed in a polymer P2 solution containing hydrophilic groups such as -OH, -NH 2 , -SO 3 H. Finally, after two more water washes and drying, the transformation from hydrophobicity to hydrophilicity is achieved, ensuring the long-term hydrophilicity of the PPS separator in the alkaline water electrolysis hydrogen production process, and also solving the safety hazards and quality stability problems during the production process with high-temperature concentrated sulfuric acid treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a flow block diagram of the present invention;

[0030] Figure 2 is a schematic diagram of the hydrophobicity of the PPS separator of the present invention before treatment;

[0031] Figure 3 is a schematic diagram of the hydrophilicity of the PPS separator of the present invention after hydrophilic treatment;

[0032] Figure 4 is a schematic diagram of the hydrophilicity of the PPS separator of the present invention after hydrophilic treatment and immersion in a 30% KOH solution. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0034] Example 1

[0035] Please refer to Figures 1-4 , the present invention provides a technical solution: a novel plasma super-hydrophilic treatment method for PPS separators, including the following steps:

[0036] S1. Gas plasma treatment: The PPS separator is subjected to plasma treatment with polar group gases to change the surface characteristics of the PPS separator; the gas flow rate during the bombardment of the PPS separator surface by the polar group gases is 25 L / min.

[0037] Atmospheric plasma treatment is selected for the plasma treatment. The polar group gas mainly includes oxygen. By bombarding the surface of the PPS diaphragm with ions, the surface of the PPS diaphragm is not only cleaned, but also the surface characteristics of the PPS diaphragm are changed through the chemical reaction of the polar group gas.

[0038] S2. After washing the plasma-treated PPS diaphragm with water and drying it, immerse it in the P1 solution for treatment and heat the P1 solution. The P1 solution is an organic compound solution.

[0039] The organic compounds in the P1 solution include: 3-aminopropyltriethoxysilane, tetraethoxysilane, tetramethoxysilane, aminopropyltrimethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-[(2,3)-epoxypropoxy]propylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, diethylenetriaminepropyltrimethoxysilane, and polyethylene diamine.

[0040] In step S2, the heating method of the P1 solution is selected as hot water coil heating, and the heating temperature of the P1 solution is controlled at 50 °C. The immersion time of the PPS diaphragm in the P1 solution is 10 min.

[0041] S3. First water wash: Put the PPS diaphragm treated by soaking in the P1 solution into the water wash tank and wash it twice with water, and introduce compressed air for stirring during the water wash process.

[0042] S4. Put the PPS diaphragm after the first water wash into the P2 solution for treatment and heat the P2 solution. The P2 solution is an organic compound solution.

[0043] The high molecular polymers in the P2 solution include: 3-(methacryloyloxy)propyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, diethylenetriaminepropyltrimethoxysilane, polyethylene diamine, and silicate.

[0044] The heating method of the P2 solution is selected as hot water coil heating, and the heating temperature of the P2 solution is controlled at 80 °C. The immersion time of the PPS diaphragm in the P2 solution is 5 min.

[0045] S5. Second water wash: Put the PPS diaphragm treated by soaking in the P2 solution into the water wash tank and wash it twice with water, and introduce compressed air for stirring during the water wash process.

[0046] In step S3 and step S5, each water wash includes two water wash processes. The time of each water wash process is 3 min, and both of the two water wash processes adopt a continuous overflow design.

[0047] During water washing, clean water is continuously replenished in the second water washing tank of the second water washing process. The clean water in the second water washing tank continuously overflows into the first water washing tank of the first water washing process, and the clean water in the first water washing tank is continuously discharged through overflows.

[0048] Air nozzles are provided at the bottoms of both the first water washing tank and the second water washing tank. One end of the air nozzle is connected to a device for discharging compressed air, and the air flow enters the bottom of the PPS diaphragm through the air nozzle to form air agitation, ensuring the cleaning effect on the PPS diaphragm.

[0049] S6. Drying: Put the PPS diaphragm after the second water washing into a dryer for drying.

[0050] The dryer is a dryer with an exhaust system. The drying temperature is set at 100 °C, and the drying time is 1.5 h.

[0051] The specific operation process of this treatment method is as follows: Treat the untreated PPS diaphragm with atmospheric plasma, use O 2 as the polar group gas, control the gas flow rate at 25 L / Min, and then immerse the PPS diaphragm after plasma treatment in the P1 solution at 50 °C for 10 minutes;

[0052] Take out the PPS diaphragm after soaking in the P1 solution, soak it in the first water washing tank for 3 minutes, and then soak it in the second water washing tank for 3 minutes. During the water washing process, clean water is continuously replenished in the second water washing tank, overflows into the first water washing tank, and the first water washing tank overflows and discharges. At the same time, turn on the compressed air to form air agitation;

[0053] Take out the PPS diaphragm after the first water washing, place it in the P2 solution at 80 °C for 5 minutes, then take out the PPS diaphragm after soaking in the P2 solution, and continue through the two water washing processes of the second time (the same as the two water washing processes of the first time). Finally, put the water-washed PPS diaphragm into the dryer, confirm that the exhaust system of the dryer is operating normally, set the temperature of the dryer at 100 °C, and the time at 1.5 h, and take it out after drying.

[0054] Further, after taking out the dried PPS diaphragm from the dryer, cut out multiple PPS diaphragm samples of 80*80 mm, take one of the samples and directly conduct a hydrophilicity performance test;

[0055] In addition, take another PPS diaphragm sample of 80*80 mm and place it in a 30% KOH solution, soak it at a temperature of 85 °C for 120 days, take it out and blow it dry, and detect the hydrophilicity performance of the diaphragm sample.

[0056] In this embodiment, the processed PPS diaphragm was installed and tested in an alkaline water electrolysis hydrogen production electrolyzer. The size of the PPS diaphragm was 100x100 mm, with a total of 22 pieces. The average thickness of the PPS diaphragm was 851 μm, and the surface density was 474 g / m 2 . Test results: average surface resistance: 0.378 Ω·cm 2 , surface resistance after alkali loss: 0.435 Ω·cm 2 , average surface resistance at 80 °C: 0.135 Ω·cm 2 , porosity: 58.49%, alkali resistance loss rate: 0.2%, high-temperature alkali resistance loss rate: 0.8%.

[0057] Example 2

[0058] The same parts as the above embodiment will not be elaborated, and the differences are

[0059] The gas flow rate when the polar group gas bombards the surface of the PPS diaphragm is 10 L / min.

[0060] In step S2, the heating method of the P1 solution is selected as hot water coil heating, and the heating temperature of the P1 solution is controlled at 30 °C. The soaking time of the PPS diaphragm in the P1 solution is 3 min.

[0061] In step S4, the heating method of the P2 solution is selected as hot water coil heating, and the heating temperature of the P2 solution is controlled at 50 °C. The soaking time of the PPS diaphragm in the P2 solution is 3 min.

[0062] In steps 3 and 5, each water wash includes two water wash processes, and the time of each water wash process is 1 min. Both water wash processes adopt a continuous flow overflow design.

[0063] In step S6, the dryer is a dryer with an exhaust system, the drying temperature is set at 95 °C, and the drying time is 0.5 h.

[0064] The specific operation process of this treatment method is as follows: The untreated PPS diaphragm is treated with atmospheric plasma, and O 2 is used as the polar group gas, and the gas flow rate is controlled at 10 L / Min. Then, the PPS diaphragm after plasma treatment is soaked in the P1 solution at 30 °C for 3 minutes;

[0065] Take out the PPS diaphragm soaked in the P1 solution, soak it in the first water wash tank for 1 minute, and then soak it in the second water wash tank for 1 minute. During the water wash process, the second water wash tank continuously replenishes clean water, overflows to the first water wash tank, and the first water wash tank overflows and discharges. At the same time, turn on the compressed air to form air agitation;

[0066] Take out the PPS diaphragm after the first water wash, soak it in the P2 solution at 50 °C for 3 minutes, then take out the PPS diaphragm soaked in the P2 solution and continue through two water washes in the second time (the same as the two water wash processes in the first time). Finally, put the water-washed PPS diaphragm into a dryer, confirm that the exhaust system of the dryer is operating normally, set the temperature of the dryer to 95 °C and the time to 0.5 h, and take it out after drying is completed.

[0067] Further, after taking out the dried PPS diaphragm from the dryer, cut out multiple PPS diaphragm samples of 80*80 mm, take one of the samples and directly conduct a hydrophilicity performance test;

[0068] In addition, take another PPS diaphragm sample of 80*80 mm and soak it in a 30% KOH solution at a set temperature of 85 °C for 120 days. After taking it out and drying it, detect the hydrophilicity performance of the diaphragm sample.

[0069] In this embodiment, the treated PPS diaphragm is installed and tested in an alkaline water electrolysis hydrogen production electrolytic cell. The size of the PPS diaphragm is 100x100 mm, with a total of 22 pieces. The average thickness of the PPS diaphragm is: 850 μm, and the areal density is: 477 g / m 2 . Test results: average surface resistance: 0.372 Ω·cm 2 , surface resistance after alkali loss: 0.431 Ω·cm 2 , average surface resistance at 80 °C: 0.129 Ω·cm 2 , porosity: 58.41%, alkali resistance loss rate: 0.22%, high-temperature alkali resistance loss rate: 0.83%.

[0070] Example 3

[0071] The same parts as the above embodiments will not be described in detail. The differences are

[0072] The gas flow rate when bombarding the surface of the PPS diaphragm with polar group gas is 15 L / min.

[0073] In step S2, the heating method of the P1 solution is selected as hot water coil heating, and the heating temperature of the P1 solution is controlled at 40 °C. The soaking time of the PPS diaphragm in the P1 solution is 7 min.

[0074] In step S4, the heating method of the P2 solution is selected as hot water coil heating, and the heating temperature of the P2 solution is controlled at 65 °C. The soaking time of the PPS diaphragm in the P2 solution is 10 min.

[0075] In steps 3 and 5, each water wash includes two water wash processes. The time of each water wash process is 2 min, and both water wash processes adopt a continuous flow overflow design.

[0076] In step S6, the dryer is set to a dryer with an exhaust system, the drying temperature is set at 97 °C, and the drying time is 1 h.

[0077] The specific operation process of this treatment method is as follows: The untreated PPS diaphragm is treated with atmospheric plasma, using O 2 as a polar group gas, the gas flow rate is controlled at 15 L / Min, and then the plasma-treated PPS diaphragm is immersed in the P1 solution at 40 °C for 7 minutes;

[0078] Take out the PPS diaphragm soaked in the P1 solution, soak it in the first water washing tank for 2 minutes, and then soak it in the second water washing tank for 2 minutes. During the water washing process, clean water is continuously added to the second water washing tank, overflowing into the first water washing tank, and the first water washing tank overflows and discharges. At the same time, turn on the compressed air to form air agitation;

[0079] Take out the PPS diaphragm after the first water washing, place it in the P2 solution at 65 °C and soak it for 10 minutes. Then take out the PPS diaphragm soaked in the P2 solution and continue to go through two water washings for the second time (the same as the two water washing processes for the first time). Finally, put the water-washed PPS diaphragm into the dryer, confirm that the exhaust system of the dryer is running normally, set the temperature of the dryer to 97 °C, and the time to 1 h. After drying, take it out.

[0080] Furthermore, after taking out the dried PPS diaphragm from the dryer, cut out multiple PPS diaphragm samples of 80*80 mm, take one of the samples and directly perform a hydrophilicity test;

[0081] In addition, take another PPS diaphragm sample of 80*80 mm and place it in a 30% KOH solution, soak it at a temperature of 85 °C for 120 days, take it out and dry it, and detect the hydrophilicity of the diaphragm sample.

[0082] In this embodiment, the treated PPS diaphragm is installed and tested in an alkaline water electrolysis hydrogen production electrolytic cell. The size of the PPS diaphragm is 100x100 mm, a total of 22 pieces. The average thickness of the PPS diaphragm is: 849 μm, and the surface density is: 476 g / m 2 . Test results: average surface resistance: 0.374 Ω·cm 2 , surface resistance after alkali loss: 0.438 Ω·cm 2 , average surface resistance at 80 °C: 0.139 Ω·cm 2 , porosity: 58.43%, alkali resistance loss rate: 0.23%, high-temperature alkali resistance loss rate: 0.82%.

[0083] Example 4

[0084] The same parts as those in the above embodiments will not be described again. The differences are as follows:

[0085] When the polar group gas bombards the surface of the PPS diaphragm, the gas flow rate is 30 L / min.

[0086] In step S2, the heating method of the P1 solution is selected as hot water coil heating, and the heating temperature of the P1 solution is controlled at 60 °C. The immersion time of the PPS diaphragm in the P1 solution is 20 min.

[0087] In step S4, the heating method of the P2 solution is selected as hot water coil heating, and the heating temperature of the P2 solution is controlled at 90 °C. The immersion time of the PPS diaphragm in the P2 solution is 15 min.

[0088] In steps 3 and 5, each water washing includes two water washing processes, and the time for each water washing process is 5 min. Both of the two water washing processes adopt a continuous flow and overflow design.

[0089] In step S6, the dryer is a dryer with an exhaust system. The drying temperature is set at 102 °C, and the drying time is 2 h.

[0090] The specific operation process of this treatment method is as follows: The untreated PPS diaphragm is treated with atmospheric plasma, and O 2 is used as the polar group gas, and the gas flow rate is controlled at 30 L / Min. Then, the PPS diaphragm after plasma treatment is immersed in the P1 solution at 60 °C for 20 minutes.

[0091] Take out the PPS diaphragm immersed in the P1 solution, soak it in the first water washing tank for 5 minutes, and then soak it in the second water washing tank for 5 minutes. During the water washing process, the second water washing tank continuously replenishes clean water, overflows to the first water washing tank, and the first water washing tank overflows and discharges. At the same time, turn on the compressed air to form air agitation.

[0092] Take out the PPS diaphragm after the first water washing, place it in the P2 solution at 90 °C and soak it for 15 minutes. Then take out the PPS diaphragm immersed in the P2 solution and continue to go through the second two water washings (the same as the two water washing processes of the first time). Finally, put the water-washed PPS diaphragm into the dryer, confirm that the exhaust system of the dryer is running normally, set the temperature of the dryer to 102 °C, and the time to 2 h. After drying, take it out.

[0093] Further, after taking out the dried PPS diaphragm from the dryer, cut out multiple PPS diaphragm samples of 80*80 mm, and take one of the samples to directly conduct a hydrophilicity performance test.

[0094] In addition, take another PPS diaphragm sample with a size of 80*80 mm and soak it in 30% KOH solution at a temperature of 85°C for 120 days. After taking it out and drying it, test the hydrophilic property of the diaphragm sample.

[0095] In this embodiment, the treated PPS diaphragm is installed and tested in an alkaline water electrolysis hydrogen production electrolytic cell. The size of the PPS diaphragm is 100x100 mm, and there are 22 pieces in total. The average thickness of the PPS diaphragm is: 854 μm, and the areal density is: 477 g / m 2 . Test results: average surface resistance: 0.372 Ω·cm 2 , surface resistance after alkali loss: 0.437 Ω·cm 2 , average surface resistance at 80°C: 0.138 Ω·cm 2 , porosity: 58.52%, alkali resistance loss rate: 0.21%, high-temperature alkali resistance loss rate: 0.83%.

[0096] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A novel plasma super-hydrophilic treatment method for PPS diaphragm, characterized in that: The following steps are involved: S1. Gas plasma treatment: The PPS diaphragm is subjected to plasma treatment with polar group gas to change the surface properties of the PPS diaphragm; S2, washing and drying the plasma-treated PPS diaphragm, and then immersing it in a P1 solution, and heating the P1 solution, where the P1 solution is an organic compound solution; S3, first water washing: put the PPS diaphragm treated with P1 solution into the water washing tank for two water washings, and introduce compressed air for stirring during the water washing process; S4, placing the PPS diaphragm after the first water washing into a P2 solution for immersion treatment, and heating the P2 solution, where the P2 solution is an organic compound solution; S5, second water washing: put the PPS diaphragm treated with P2 solution into the water washing tank for two water washings, and introduce compressed air for stirring during the water washing process; S6. Drying: Put the PPS diaphragm after the second water washing into a dryer for drying.

2. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 1, characterized in that: In step S1, atmospheric plasma treatment is used for plasma treatment. The polar group gas mainly includes oxygen. The surface of the PPS membrane is cleaned by bombarding the surface of the PPS membrane with ions, and the surface properties of the PPS membrane are changed by the chemical reaction of the polar group gas.

3. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 1, characterized in that: The gas flow rate when the polar group gas bombards the surface of the PPS diaphragm is 10-30L / min.

4. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 1, characterized in that: In step S2, the organic compounds in the P1 solution include: 3-aminopropyltriethoxysilane, tetraethoxysilane, tetramethoxysilane, aminopropyltrimethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-[(2,3)-epoxypropyloxy]propylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, diethylenetriaminepropyltrimethoxysilane, and polyethylenediamine.

5. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 1, characterized in that: In step S2, the heating method of the P1 solution is to use a hot water coil for heating, and the heating temperature of the P1 solution is controlled at 30-60°C, and the immersion time of the PPS diaphragm in the P1 solution is 3-20 minutes.

6. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 1, characterized in that: In step 3 and step 5, each water washing includes two water washing processes, each water washing process takes 1-5 minutes, and both water washing processes adopt a continuous overflow design.

7. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 6, characterized in that: During water washing, clean water is continuously added to the second washing tank in the second washing process, and the clean water in the second washing tank continuously overflows into the first washing tank in the first washing process, and the clean water in the first washing tank is continuously discharged through overflow.

8. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 7, characterized in that: Air nozzles are provided at the bottom of the first and second washing tanks. One end of the air nozzles is connected to a device for discharging compressed air. The airflow enters the bottom of the PPS diaphragm through the air nozzles to form air stirring, thereby ensuring the cleaning effect on the PPS diaphragm.

9. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 1, characterized in that: In step S4, the heating method of the P2 solution is to use a hot water coil for heating, and the heating temperature of the P2 solution is controlled at 50-90° C. The immersion time of the PPS diaphragm in the P2 solution is 3-15 min.

10. A novel plasma super-hydrophilic treatment method for PPS diaphragm according to claim 1, characterized in that: In step S6, the dryer is set to be a dryer with an exhaust system, the drying temperature is set at 95-102°C, and the drying time is 0.5-2h.

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