Novel PPS isolating membrane super-hydrophilic treatment method
Through acidification treatment and superhydrophilic treatment methods, the problem of insufficient hydrophilicity of PPS membranes is solved, and a superhydrophilic PPS membrane that is stable in a high-temperature alkaline environment is created, which improves hydrogen production efficiency and reduces costs.
Patent Information
- Application Number
- CN202311832236.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-28
- Publication Date
- 2025-03-28
AI Technical Summary
The hydrophilicity of the PPS separator is too poor, resulting in excessive internal resistance of the electrolytic cell and reduced hydrogen production efficiency. The existing hydrophilic treatment methods are unstable in high-temperature alkaline environments or require strict control of components and ratios.
The acidification treatment and superhydrophilic treatment methods are adopted, including acidification treatment of the PPS membrane in hot concentrated sulfuric acid, and then soaking in organic compounds and polymer compounds containing hydrophilic groups to ensure the superhydrophilicity and stability of the membrane.
A super hydrophilic and extremely stable PPS diaphragm is produced, which can maintain hydrophilicity after soaking in 30% KOH solution for 4 months, reducing preparation costs, simplifying the process flow, and the process is green and environmentally friendly.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of hydrophilic treatment of PPS isolation membranes, and in particular to a novel super-hydrophilic treatment method for PPS isolation membranes. Background Art
[0002] Hydrogen energy is an ideal, efficient and clean energy source. The alkaline water electrolysis hydrogen production process occupies a dominant position in the hydrogen production industry. The main functions of the diaphragm in the alkaline water electrolysis hydrogen production electrolyzer are: 1. Isolating the hydrogen and oxygen produced in the water electrolysis process; 2. Allowing the ions in the electrolyzer liquid to move freely. The hydrophilicity of the diaphragm directly affects the internal resistance of the electrolyzer.
[0003] The new composite diaphragm based on polyphenylene sulfide (PPS) fabric is widely used due to its excellent heat resistance, mechanical strength and electrical properties. However, the hydrophilicity of PPS fabric is too poor, which makes the internal resistance of the electrolyzer using PPS diaphragm too large and the hydrogen production efficiency reduced. Therefore, the PPS diaphragm needs to be hydrophilic treated.
[0004] There are two main methods for hydrophilic treatment of PPS diaphragms: 1. One is chemical treatment of PPS diaphragms: attaching hydrophilic functional groups (-SO3H, -COOH, etc.) to the molecular chains of PPS, but these functional groups are not stable in high-temperature alkaline electrolytes. 2. Coating the surface of the PPS diaphragm with a mixture of polymer and zirconium oxide to improve its hydrophilicity, forming a composite diaphragm similar to a Sandwich structure. The use of this process must strictly control the composition and ratio of polymer and zirconium oxide as well as the coating thickness to ensure its hydrophilicity and reduce the internal resistance of the electrolytic cell. At the same time, the air tightness of the PPS diaphragm is also more or less affected. In addition, its adhesion will be reduced in high-temperature alkaline electrolytes for a long time, and there is a risk of peeling. Summary of the invention
[0005] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art, and to provide a novel super-hydrophilic treatment method for a PPS separator, which does not destroy the internal structure and pore structure of the PPS separator, and manufactures a super-hydrophilic and extremely stable PPS separator. The hydrophilicity of the surface of the PPS separator does not decrease after being immersed in a 30% KOH solution (50-90° C.) for 4 months, and the surface of the treated PPS separator does not need to be coated with a mixture of a polymer and zirconium oxide, so the preparation cost is greatly reduced. At the same time, the production process is simple, easy to operate, and green and environmentally friendly.
[0006] The present invention also provides a method for super-hydrophilic treatment of the novel PPS isolation membrane, comprising the following steps: S1. Acidification treatment: soak the PSS isolation membrane in hot concentrated sulfuric acid; S2. Washing and drying: The PSS isolation membrane soaked in S1 is washed with deionized water and then dried; S3. Super hydrophilic treatment: The PSS isolation membrane treated in S2 is immersed in an organic compound and a polymer compound containing a hydrophilic group; The organic compound containing hydrophilic groups includes organic compounds containing hydrophilic groups such as -OH, -NH2, -SO3H, solvents, and silicate; The polymer compound includes 3-aminopropyl triethoxysilane, 3-(2,3-epoxypropyloxy)propyl trimethoxysilane, 3-(isobutyleneoxy)propyl trimethoxysilane, tetraethoxysilane, tetraethyl vinyl silicate, tetramethoxysilane, aminopropyl trimethoxysilane, N-methyl-3-aminopropyl trimethoxysilane, 3-glycidyloxypropyl triethoxysilane, 3-glycidyloxypropyl methyl diethoxysilane, 3-chloropropyl trimethoxysilane, 3-[(2,3)-epoxypropyloxy]propyl methyl dimethoxysilane, 3-aminopropyl trimethoxysilane, diethylenetriamine propyl trimethoxysilane, and polyethylenediamine; S4. Final treatment: Wash and dry the PSS isolation membrane treated in S3.
[0007] According to a novel super-hydrophilic treatment method for a PPS isolation membrane provided by the present invention, the preparation process of the hot concentrated sulfuric acid is as follows: 1) Add concentrated sulfuric acid into a clean preparation tank until the required volume is reached; 2) Heat the concentrated sulfuric acid in the tank to 50℃-80℃. The preparation is complete and set aside for later use.
[0008] According to a novel super-hydrophilic treatment method for a PPS isolation membrane provided by the present invention, the configuration process of the organic compound containing a hydrophilic group is as follows: 1) Dissolve an organic compound containing hydrophilic groups such as -OH, -NH2, -SO3H in a solvent and stir for a period of time to form a solution; 2) Add a small amount of silicate to the solution and continue stirring for a while to form a working solution; 3) Add the working solution into a clean tank until the volume reaches the specified volume; 4) Heat the working liquid in the tank to 30℃-90℃ and the liquid preparation is completed.
[0009] According to a novel super-hydrophilic treatment method for a PPS isolation membrane provided by the present invention, the immersion time in S1 is 3-20 minutes, and the immersion time in S3 is 3-30 minutes.
[0010] According to a novel method for super-hydrophilic treatment of a PPS separator provided by the present invention, the surface of the PPS separator after treatment is a super-hydrophilic surface of the single molecule mid-layer. Beneficial Effects
[0011] The present invention does not destroy the internal structure and pore structure of the PPS diaphragm, and manufactures a super-hydrophilic and extremely stable PPS diaphragm. The hydrophilicity of the surface of the PPS diaphragm does not decrease after being immersed in a 30% KOH solution (50° C.-90° C.) for 4 months.
[0012] The surface of the PPS diaphragm treated by the present invention does not need to be coated with a mixture of polymer and zirconium oxide, and the preparation cost is greatly reduced.
[0013] The production process of the invention is simple, easy to operate and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention is further described below in conjunction with the accompanying drawings and embodiments; Figure 1 A schematic diagram of a novel super-hydrophilic treatment method for a PPS isolation membrane according to the present invention; Figure 2 This is a comparison chart of the results of experiment 1 of a novel super-hydrophilic treatment method for PPS isolation membrane of the present invention. Implementation
[0015] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.
[0016] Reference Figure 1 The present invention provides a novel method for super-hydrophilic treatment of a PPS isolation membrane, which comprises the following steps: S1. Acidification treatment: soak the PSS isolation membrane in hot concentrated sulfuric acid; S2. Washing and drying: The PSS isolation membrane soaked in S1 is washed with deionized water and then dried; S3. Super hydrophilic treatment: The PSS isolation membrane treated in S2 is immersed in an organic compound and a polymer compound containing a hydrophilic group; Organic compounds containing hydrophilic groups include organic compounds containing hydrophilic groups such as -OH, -NH2, -SO3H, solvents, and silicates; The polymer compounds include 3-aminopropyl triethoxysilane, 3-(2,3-epoxypropyloxy)propyl trimethoxysilane, 3-(isobutyleneoxy)propyl trimethoxysilane, tetraethoxysilane, tetraethyl vinyl silicate, tetramethoxysilane, aminopropyl trimethoxysilane, N-methyl-3-aminopropyl trimethoxysilane, 3-glycidyloxypropyl triethoxysilane, 3-glycidyloxypropyl methyl diethoxysilane, 3-chloropropyl trimethoxysilane, 3-[(2,3)-epoxypropyloxy]propyl methyl dimethoxysilane, 3-aminopropyl trimethoxysilane, diethylenetriamine propyl trimethoxysilane, and polyethylenediamine; S4. Final treatment: Wash and dry the PSS isolation membrane treated in S3.
[0017] The preparation process of hot concentrated sulfuric acid is as follows: 1) Add concentrated sulfuric acid into a clean preparation tank until the required volume is reached; 2) Heat the concentrated sulfuric acid in the tank to 50℃-80℃. The preparation is complete and set aside for later use.
[0018] The configuration process of organic compounds containing hydrophilic groups is as follows: 1) Dissolve an organic compound containing hydrophilic groups such as -OH, -NH2, -SO3H in a solvent and stir for a period of time to form a solution; 2) Add a small amount of silicate to the solution and continue stirring for a while to form a working solution; 3) Add the working solution into a clean tank until the volume reaches the specified volume; 4) Heat the working liquid in the tank to 30℃-90℃ and the liquid preparation is completed.
[0019] The soaking time in S1 is 3-20 minutes, and the soaking time in S3 is 3-30 minutes.
[0020] The surface of the PPS membrane after treatment is a super hydrophilic surface at the single molecule level.
[0021] Experiment 1: The pps diaphragm treated by the present invention and the diaphragm without treatment were tested: Lay the treated PPS diaphragm and the untreated PPS diaphragm flat on the table; Slowly drip water onto the surface of the pps diaphragm through a dropper; Number of water drops 1 5 10 15 Treated diaphragm Rapid absorption Rapid absorption Rapid absorption Rapid absorption Untreated diaphragm Forming water droplets Forming water droplets Forming water droplets Forming water droplets Comparative Example 1 The PPS nonwoven fabric is immersed in an aqueous solution of a strong oxidizing acid to undergo a grafting reaction until the PPS nonwoven fabric turns yellow, and then taken out and rinsed to neutrality to obtain an oxidatively grafted PPS nonwoven fabric; The cellulose treated with the silane coupling agent is evenly coated on the surface of the PPS non-woven fabric after oxidation grafting; The hydrophilically modified inorganic nanoparticles are mixed with a demulsifier and dispersed to form a suspension, and then the suspension is evenly coated on the surface of the cellulose coated with the silane coupling agent of the oxidatively grafted PPS non-woven fabric; The product obtained in step 3 is hot-pressed to obtain a super-hydrophilic PPS composite fiber membrane; Comparative Example 2 A mixture of polymer and zirconium oxide is coated on the surface of the PSS diaphragm; Mixing zirconium oxide with a polymer to form a hydrophilic coating; The hydrophilic coating is applied on the surface of the PSS diaphragm to form a hydrophilic PPS material; time 15 days January February April The present invention Rapid absorption Rapid absorption Rapid absorption Rapid absorption Comparative Example 1 Rapid absorption Rapid absorption Slow absorption Slow absorption Comparative Example 2 Rapid absorption Rapid absorption Rapid absorption Rapid absorption time 15 days January February April The present invention Rapid absorption Rapid absorption Rapid absorption Rapid absorption Comparative Example 1 Rapid absorption Slow absorption Slow absorption Slow absorption Comparative Example 2 Rapid absorption Rapid absorption Slow absorption Slow absorption High temperature KOH solution (temperature 50℃-90℃) It can be seen from the above table that, compared with the existing treatment methods, the present invention has better alkali resistance and can adapt to more complex environments.
[0022] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present invention.
Claims
1. A novel super-hydrophilic treatment method for PPS isolation membrane, characterized in that: The following steps are involved: S1. Acidification treatment: soak the PSS isolation membrane in hot concentrated sulfuric acid; S2. Washing and drying: The PSS isolation membrane soaked in S1 is washed with deionized water and then dried; S3. Super hydrophilic treatment: The PSS isolation membrane treated in S2 is immersed in an organic compound and a polymer compound containing a hydrophilic group; The organic compound containing the hydrophilic group includes organic compounds containing hydrophilic groups such as -OH, -NH2, -SO3H, solvents, and silicate; The polymer compound includes 3-aminopropyl triethoxysilane, 3-(2,3-epoxypropyloxy)propyl trimethoxysilane, 3-(isomethacryloyloxy)propyl trimethoxysilane, tetraethoxysilane, tetraethyl vinyl silicate, tetramethoxysilane, aminopropyl trimethoxysilane, N-methyl-3-aminopropyl trimethoxysilane, 3-glycidyloxypropyl triethoxysilane, 3-glycidyloxypropyl methyl diethoxysilane, 3-chloropropyl trimethoxysilane, 3-[(2,3)-epoxypropyloxy]propyl methyl dimethoxysilane, 3-aminopropyl trimethoxysilane, diethylenetriamine propyl trimethoxysilane, and polyethylenediamine; S4. Final treatment: Wash and dry the PSS isolation membrane treated in S3.
2. A novel super-hydrophilic treatment method for PPS isolation membrane according to claim 1, characterized in that: The preparation process of the hot concentrated sulfuric acid is as follows: Add concentrated sulfuric acid to a clean preparation tank until the required volume is reached; Heat the concentrated sulfuric acid in the tank to 50℃-80℃, the preparation is completed and set aside for later use.
3. A novel super-hydrophilic treatment method for PPS isolation membrane according to claim 1, characterized in that: The configuration process of the organic compound containing a hydrophilic group is as follows: Dissolve an organic compound containing hydrophilic groups such as -OH, -NH2, -SO3H in a solvent and stir for a period of time to form a solution; Add a small amount of silicate to the solution and continue stirring for a while to form a working solution; Add the working solution to a clean tank until the volume reaches the specified volume; Heat the working liquid in the tank to 30℃-90℃ and the liquid preparation is completed.
4. A novel super-hydrophilic treatment method for PPS isolation membrane according to claim 1, characterized in that: The soaking time in S1 is 3-20 minutes, and the soaking time in S3 is 3-30 minutes.
5. A novel super-hydrophilic treatment method for PPS isolation membrane according to claim 1, characterized in that: The surface of the PPS membrane after treatment is a super-hydrophilic surface at the monomolecular level.