Diaphragm with high durability and preparation method and application thereof

Abstract

The invention relates to the technical field of alkaline water electrolysis hydrogen production, in particular to a high-durability diaphragm and a preparation method and application thereof.The preparation method comprises the steps that S1, firstly, cerium nitrate hydrate is dissolved in deionized water, then a surfactant and a gelatinizing agent are added into the deionized water in sequence, the mixture is stirred to be uniform, and a cerium-containing solution is formed; s2, the pH value of the cerium-containing solution is adjusted to be in the range of 0.5-5, then the temperature of the cerium-containing solution is increased for a gel forming reaction, and cerium-containing sol is prepared; and S3, padding the sulfonated polyphenylene sulfide diaphragm in the cerium-containing sol for a plurality of times to enable the average gel content of the sulfonated polyphenylene sulfide diaphragm to be 40-80%, and then putting the sulfonated polyphenylene sulfide diaphragm into heating equipment to be subjected to stepped heating and drying treatment, so as to obtain the diaphragm with high durability after the treatment is completed. The diaphragm with high durability has excellent oxidation resistance, relatively strong sulfonate radical shedding performance, relatively high breaking strength, wear resistance and water flow impact resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production by alkaline water electrolysis, and in particular to a diaphragm with high durability, a preparation method thereof, and applications thereof. Background Art

[0002] Hydrogen energy is the chemical energy released by the chemical reaction of hydrogen and oxygen. It is a clean energy source that is being rapidly developed and utilized. Currently, commonly used hydrogen production technologies include alkaline water electrolysis, proton exchange membrane (PEM) water electrolysis, and anion exchange membrane water electrolysis. Among them, alkaline water electrolysis hydrogen production technology refers to the process of electrolyzing water to produce hydrogen using a KOH solution with a mass concentration of approximately 30% or a NaOH solution with a mass concentration of 26%. During the electrolysis process, water molecules gain electrons at the cathode to form hydrogen gas and hydroxide ions. The hydroxide ions then pass through the diaphragm to the anode to produce oxygen and water. In alkaline water electrolysis hydrogen production technology, asbestos cloth, polyphenylene sulfide (PPS), or polysulfone (PSF) fiber fabrics are typically used as diaphragms to separate the electrodes and conduct hydroxide (OH-) in the electrolyte to connect the internal circuit. However, the poor hydrophilicity of polyphenylene sulfide fiber fabrics can increase the resistance within the electrolyzer, thereby increasing the energy consumption of the alkaline water electrolysis system and leading to excessively high electrolysis costs.

[0003] Although sulfonated polyphenylene sulfide (SPPS), a material obtained by introducing sulfonic acid groups into the polyphenylene sulfide molecular chain through a sulfonation reaction, can significantly improve the hydrophilicity of the separator made from it due to the introduction of sulfonic acid groups, the thermal stability of sulfonated polyphenylene sulfide is reduced compared to that of polyphenylene sulfide. In addition, due to the inherent material properties of sulfonated polyphenylene sulfide, the separator made from it has significant deficiencies in oxidation resistance. When the separator is in the actual working environment, it will be attacked and affected by multiple factors: on the one hand, the continuous application of voltage will have a negative impact on it; on the other hand, the attack of active free radicals such as hydroxyl radicals (OH·) and superoxide radicals (O2·) will gradually destroy the chemical structure of the separator, causing the sulfonic acid groups to continuously fall off the separator surface.

[0004] As the diaphragm ages, especially after being used for more than one year, its sulfonation degree will show a clear downward trend. This reduction in sulfonation will trigger a series of chain reactions. First, the decrease in sulfonation directly weakens the hydrophilicity of the diaphragm, which in turn leads to a decrease in the proton conductivity of the diaphragm and an increase in the ohmic resistance, thereby increasing the overall energy consumption of the alkaline water electrolysis system. Second, the decrease in sulfonation will also make it difficult for bubbles generated in the electrolytic cell to smoothly detach from the diaphragm surface, causing bubbles to accumulate in the electrolytic cell, which in turn causes increased voltage fluctuations. This voltage instability will not only affect the smoothness of the electrolysis process, but will also significantly reduce the overall efficiency of the hydrogen production system, posing a threat to the long-term stable operation of the system.

[0005] The present invention provides a highly durable diaphragm and a preparation method and application thereof, so as to solve the problems in the prior art that the existing diaphragms have significant deficiencies in antioxidant performance and sulfonate groups are easily detached. Summary of the Invention

[0006] The purpose of the present invention is to provide a highly durable diaphragm and a preparation method and application thereof, so as to solve the problems existing in the prior art such as the significant deficiencies in the antioxidant properties of the existing diaphragms and the easy shedding of sulfonate groups.

[0007] The technical solution of the present invention is: a method for preparing a diaphragm with high durability, comprising the following steps:

[0008] S1. Dissolving hydrated cerium nitrate in deionized water, then sequentially adding a surfactant and a gelling agent to the deionized water and stirring uniformly to form a cerium-containing solution; wherein the gelling agent is any one or more of an organic acid, a hydroxyl- or carbonyl-containing organic compound, and ammonia water;

[0009] The surfactant is any one or more of a sodium salt surfactant, a sulfate ester surfactant, and an organic alcohol surfactant;

[0010] S2, adjusting the pH value of the cerium-containing solution to a range of 0.5-5, and then increasing the temperature of the cerium-containing solution to perform a gel-forming reaction to prepare a cerium-containing sol;

[0011] S3. Immerse the sulfonated polyphenylene sulfide membrane in a cerium-containing sol several times to make the average glue content on the sulfonated polyphenylene sulfide membrane 40%-80%. Then, place the sulfonated polyphenylene sulfide membrane in a heating device for a step-by-step temperature drying treatment. After the treatment is completed, a membrane with high durability is obtained; wherein the membrane with high durability includes the sulfonated polyphenylene sulfide membrane and cerium oxide attached to the sulfonated polyphenylene sulfide membrane.

[0012] Preferably, in the highly durable separator, the attachment amount of the cerium oxide is 0.1% to 10% of the weight of the sulfonated polyphenylene sulfide separator.

[0013] Preferably, in the cerium-containing solution, the mass ratio of the hydrated cerium nitrate, the gelling agent, the surfactant and the deionized water is (0.01-0.3):(0.01-0.45):(0.0001-0.01):1.

[0014] Preferably, the organic acid is any one or more of oxalic acid, citric acid, malic acid, and tartaric acid; and the hydroxyl- or carbonyl-containing organic compound is any one or more of ethylene glycol, polyethylene glycol, polyvinyl pyrrolidone, and chitosan.

[0015] Preferably, the gelling agent is an organic acid; the organic acid is citric acid.

[0016] Preferably, the sodium salt active agent is any one or more of sodium tripolyphosphate, sodium pyrophosphate, sodium hexametaphosphate, trisodium phosphate, sodium carbonate, sodium dodecylbenzenesulfonate, sodium lauryl sulfate, and sodium octylsulfonate;

[0017] The sulfate active agent is fatty alcohol polyoxyethylene ether sulfate and / or dodecyl polyoxyethylene ether sulfate;

[0018] The organic alcohol active agent is any one or more of ethanol, isopropanol, ethylene glycol, and propylene glycol.

[0019] Preferably, the surfactant is a sodium salt surfactant; the sodium salt surfactant is sodium tripolyphosphate and / or sodium pyrophosphate.

[0020] Preferably, in step S2, the reaction temperature of the gelling reaction is 40-90° C., and the reaction time is 0.5-50 h;

[0021] The step-by-step drying process includes: a first-stage drying process at 70-100° C. and a baking process at 120-200° C.

[0022] The present invention also provides a diaphragm with high durability, which is prepared by the above preparation method.

[0023] The present invention also provides applications of the above-mentioned diaphragm with high durability, including application as a diaphragm for producing hydrogen by electrolysis of water in a water electrolysis hydrogen production device.

[0024] Compared with the prior art, the advantages of the present invention are:

[0025] (1) The present invention provides a highly durable diaphragm and its preparation method and application. The highly durable diaphragm is obtained by treating a sulfonated polyphenylene sulfide diaphragm by a sol-gel method to form a cerium oxide protective layer on its surface and in the gaps between its fibers. The diaphragm has excellent antioxidant properties and strong sulfonate radical shedding properties. Moreover, the cerium oxide protective layer on the surface can give the highly durable diaphragm a higher breaking strength, excellent wear resistance, and good water flow impact resistance. At the same time, the preparation method can control the type of surfactant. , gelation reaction temperature, gelation reaction time and other parameters to regulate the crystal form of cerium oxide, so that all aspects of the performance of the highly durable diaphragm are further improved; thus, when the highly durable diaphragm is used as a water electrolysis hydrogen production diaphragm in a hydrogen production equipment, the water electrolysis hydrogen production diaphragm can be endowed with long-term voltage stability, extremely high oxidation resistance, alkali resistance and resistance to sulfonate shedding, which helps to extend the service life of the water electrolysis hydrogen production diaphragm; it solves the problems in the prior art that the existing diaphragms have significant deficiencies in oxidation resistance and easy shedding of sulfonate groups. DETAILED DESCRIPTION

[0026] The present invention will be described in further detail below with reference to specific embodiments:

[0027] The present application provides a method for preparing a diaphragm with high durability, which specifically comprises the following steps:

[0028] S1. Weigh hydrated cerium nitrate, a gelling agent, a surfactant, and deionized water in proportion. Then, dissolve the weighed hydrated cerium nitrate in deionized water, and then add the weighed surfactant and gelling agent to the deionized water in sequence, stirring evenly to form a cerium-containing solution. The mass ratio of hydrated cerium nitrate, gelling agent, surfactant, and deionized water is (0.01-0.3):(0.01-0.45):(0.0001-0.01):1. The hydrated cerium nitrate can be selected from hexahydrated cerium nitrate, etc.; in the process of dissolving the hydrated cerium nitrate in the deionized water, the temperature of the deionized water can be increased to 40-80°C and stirred to allow the hydrated cerium nitrate to dissolve quickly and completely in the deionized water. The gelling agent can be selected from one or more of organic acids, hydroxyl- or carbonyl-containing organic compounds, ammonia water, etc.; the organic acid can be one or more of oxalic acid, citric acid, malic acid, tartaric acid, etc.; the hydroxyl- or carbonyl-containing organic compound is preferably one or more of ethylene glycol, polyethylene glycol, polyvinyl pyrrolidone, chitosan, etc. Further, the gelling agent is preferably an organic acid; more preferably, citric acid is used. The surfactant is one or more of sodium salt surfactants, sulfate ester surfactants, organic alcohol surfactants, etc.; the sodium salt surfactant can be selected from one or more of sodium tripolyphosphate, sodium pyrophosphate, sodium hexametaphosphate, trisodium phosphate, sodium carbonate, sodium dodecylbenzenesulfonate, sodium lauryl sulfate, sodium octylsulfonate, etc.; the sulfate ester surfactant is preferably fatty alcohol polyoxyethylene ether sulfate and / or lauryl polyoxyethylene ether sulfate; the organic alcohol surfactant is one or more of ethanol, isopropanol, ethylene glycol, propylene glycol, etc. Furthermore, the surfactant is preferably a sodium salt surfactant, and more preferably sodium tripolyphosphate and / or sodium pyrophosphate.

[0029] S2. Adjusting the pH of the cerium-containing solution to a range of 0.5-5, then raising the temperature of the cerium-containing solution to initiate a gelation reaction, thereby preparing a cerium-containing sol. The gelation reaction temperature should be controlled within a range of 40-90° C., and the reaction time should be 0.5-50 hours. In adjusting the pH of the cerium-containing solution, a saturated sodium carbonate solution, sodium bicarbonate solution, or saturated citric acid solution can be used as an adjusting agent. Alternatively, a 0.5-1M sodium hydroxide solution or a 0.5-1M hydrochloric acid solution can be used.

[0030] S3. The sulfonated polyphenylene sulfide membrane is dipped and rolled several times in a cerium-containing sol until the average glue content on the sulfonated polyphenylene sulfide membrane is 40%-80%. The sulfonated polyphenylene sulfide membrane is then placed in a heating device for a step-by-step drying process. After the process is completed, a cerium oxide protective layer can be formed on the surface of the sulfonated polyphenylene sulfide membrane and in the gaps between the fibers, thereby obtaining a highly durable membrane. The highly durable membrane comprises a sulfonated polyphenylene sulfide membrane and a layer of cerium oxide attached to the sulfonated polyphenylene sulfide membrane; and the amount of cerium oxide attached to the highly durable membrane (dry weight) is 0.1%-10% of the dry weight of the sulfonated polyphenylene sulfide membrane itself. The step-by-step drying process includes a first stage drying process at 70-100°C and a second stage drying process at 120-200°C.

[0031] The present application also provides a diaphragm with high durability, which is prepared by the above preparation method.

[0032] In addition, the present application also provides applications of the highly durable diaphragm, including application as a diaphragm for producing hydrogen by electrolysis of water in a water electrolysis hydrogen production device.

[0033] Example 1

[0034] S1. Weigh 60 g of cerium nitrate hexahydrate, 90 g of citric acid, 0.2 g of sodium tripolyphosphate, and 500 mL of deionized water; then, add the cerium nitrate hexahydrate to the deionized water, raise the temperature of the deionized water to 60° C., and stir until the cerium nitrate hexahydrate is completely dissolved; then, add the sodium tripolyphosphate to the deionized water, stir thoroughly, and evenly disperse; then, slowly add the citric acid to the deionized water, stir until dissolved, to form a cerium-containing solution;

[0035] S2, adjusting the pH value of the cerium-containing solution to 1.5, then raising the temperature of the cerium-containing solution to 60° C. to perform a gel-forming reaction, and stirring for 8 hours to obtain a cerium-containing sol;

[0036] S3: Immerse the sulfonated polyphenylene sulfide membrane in a cerium-containing sol at 60°C for 3 minutes, remove the membrane, and roll off excess sol to achieve an average adhesive content of 50% on the membrane. Repeat the immersion of the membrane in the cerium-containing sol once more, and roll off excess sol to achieve an average adhesive content of 63% on the membrane. The membrane is then placed in an oven and dried at 80°C for 15 minutes, followed by drying at 150°C for 5 minutes. After this drying, a highly durable membrane, P1, is obtained. The amount of cerium oxide attached to the surface of the highly durable membrane, P1, is 5.2% of the dry weight of the sulfonated polyphenylene sulfide membrane.

[0037] Example 2

[0038] S1. Weigh 90 g of cerium nitrate hexahydrate, 135 g of citric acid, 0.2 g of sodium tripolyphosphate, and 500 mL of deionized water; then, add the cerium nitrate hexahydrate to the deionized water, raise the temperature of the deionized water to 60° C., and stir until the cerium nitrate hexahydrate is completely dissolved; then, add the sodium tripolyphosphate to the deionized water, stir thoroughly, and evenly disperse; then, slowly add the citric acid to the deionized water, stir until dissolved, to form a cerium-containing solution;

[0039] S2, adjusting the pH value of the cerium-containing solution to 1.35, then raising the temperature of the cerium-containing solution to 60° C. to perform a gel-forming reaction, and stirring for 12 hours to obtain a cerium-containing sol;

[0040] S3: Immerse the sulfonated polyphenylene sulfide membrane in a cerium-containing sol at 60°C for 3 minutes, remove the membrane, and roll off excess sol to achieve an average adhesive content of 60% on the membrane. Repeat the immersion of the membrane in the cerium-containing sol once more, roll off excess sol, and achieve an average adhesive content of 70% on the membrane. The membrane is then placed in an oven and dried at 80°C for 15 minutes, then at 150°C for 5 minutes. After this drying process, a highly durable membrane, P2, is obtained. The amount of cerium oxide attached to the surface of the highly durable membrane, P2, is 9.4% of the dry weight of the sulfonated polyphenylene sulfide membrane.

[0041] Example 3

[0042] In this example, 30g of cerium nitrate hexahydrate, 45g of citric acid, 0.15g of sodium tripolyphosphate, and 500mL of deionized water were weighed. A cerium-containing solution and cerium-containing sol were prepared using the same methods as in Example 1. Padding and step-by-step drying were performed using the same methods as in Example 1 to produce a highly durable membrane, P3. The pH of the cerium-containing sol was 1.65, and the gelling reaction lasted for 6 hours. The amount of cerium oxide attached to the surface of the highly durable membrane, P3, was 3.1% of the dry weight of the sulfonated polyphenylene sulfide membrane.

[0043] Example 4

[0044] In this example, 60g of cerium nitrate hexahydrate, 90g of citric acid, 0.2g of sodium dodecylbenzenesulfonate, and 500mL of deionized water were weighed. A cerium-containing solution and cerium-containing sol were prepared using the same methods as in Example 1. Padding and step-by-step drying were performed using the same methods as in Example 1 to produce a highly durable membrane, P4. The pH of the cerium-containing sol was 1.5, and the gelling reaction lasted 9 hours. The amount of cerium oxide attached to the surface of the highly durable membrane, P4, was 4.3% of the dry weight of the sulfonated polyphenylene sulfide membrane.

[0045] Example 5

[0046] In this example, 180g of cerium nitrate hexahydrate, 270g of citric acid, 0.4g of sodium tripolyphosphate, and 500mL of deionized water were weighed. A cerium-containing solution and cerium-containing sol were prepared using the same methods as in Example 1. Padding and step-by-step drying were performed using the same methods as in Example 1 to produce a highly durable membrane, P5. The pH of the cerium-containing sol was 1.0, and the gelling reaction lasted 18 hours. The amount of cerium oxide attached to the surface of the highly durable membrane, P5, was 12.1% of the dry weight of the sulfonated polyphenylene sulfide membrane.

[0047] Example 6

[0048] In this example, 2g of cerium nitrate hexahydrate, 3g of citric acid, 0.005g of sodium tripolyphosphate, and 500mL of deionized water were weighed. A cerium-containing solution and cerium-containing sol were prepared using the same methods as in Example 1. Padding and step-by-step drying were performed using the same methods as in Example 1 to produce a highly durable membrane, P6. The pH of the cerium-containing sol was 3.0, and the gelling reaction lasted 2 hours. The amount of cerium oxide attached to the surface of the highly durable membrane, P6, was 0.05% of the dry weight of the sulfonated polyphenylene sulfide membrane.

[0049] Comparative Example 1

[0050] The same sulfonated polyphenylene sulfide membrane Q1 as that in Example 1 was selected, and the sulfonated polyphenylene sulfide membrane was not treated by the sol-gel method.

[0051] The performance of the highly durable membranes P1-P6 prepared in Examples 1-6 and the sulfonated polyphenylene sulfide membrane Q1 in Comparative Example 1 was tested; specifically, the cerium oxide content on the surface of the highly durable membranes P1-P6 was calculated based on the weight difference; the sulfonated polyphenylene sulfide membrane Q1 in Comparative Example 1 and the highly durable membranes P1-P6 in Examples 1-6 were placed in a Fenton solution (28% H2O2, 30ppm ferrous sulfate) and treated at 80°C to simulate the environment of a large amount of hydroxyl radicals OH· and superoxide radicals O2· generated in the alkali tank, and the performance of the sulfonated polyphenylene sulfide membrane Q1 and the highly durable membranes P1-P6 were tested. At the same time, the surface oxygen content of the sulfonated polyphenylene sulfide membrane Q1 and the highly durable membranes P1-P6 before and after the Fenton solution treatment was directly detected by XPS. The breaking strength of the sulfonated polyphenylene sulfide membrane Q1 and the highly durable membranes P1-P6 was determined based on the strength test standard GB / T 3923.1-1997. In addition, the surface resistance of the membranes was measured with reference to ST / J 10171.5-91. The specific test results are shown in Table 1.

[0052] Table 1. Performance test results of high-durability membranes P1-P6 and sulfonated polyphenylene sulfide membrane Q1

[0053]

[0054] The performance of the highly durable membranes P1-P6 prepared in Examples 1-6 was compared with that of the sulfonated polyphenylene sulfide membrane Q1 in Comparative Example 1. As shown in Table 1, the surface resistance of the highly durable membranes P1-P6 prepared in Examples 1-6 was slightly greater than that of the sulfonated polyphenylene sulfide membrane Q1 in Comparative Example 1; and the sulfonate shedding ratio of the membranes P1-P6 after 24 hours of Fenton treatment was lower than that of the sulfonated polyphenylene sulfide membrane Q1 in Comparative Example 1 after 24 hours of Fenton treatment; and the reduction in surface oxygen content of the membranes P1-P6 after 24 hours of Fenton treatment was also lower than that of the sulfonated polyphenylene sulfide membrane Q1 in Comparative Example 1 after 24 hours of Fenton treatment. The reduction in surface oxygen content after 4 hours; and its warp breaking strength is higher than the warp breaking strength of the sulfonated polyphenylene sulfide membrane Q1 in Comparative Example 1; it further illustrates that a cerium oxide protective layer is formed on the surface of the sulfonated polyphenylene sulfide membrane and in the fiber gaps to obtain a highly durable membrane, which can make the highly durable membrane have strong resistance to sulfonate group shedding and excellent antioxidant performance; the cerium oxide protective layer has the effect of protecting the sulfonate groups on the sulfonated polyphenylene sulfide membrane; at the same time, the cerium oxide protective layer can effectively improve the breaking strength of the sulfonated polyphenylene sulfide membrane as well as improve the wear resistance and water flow impact resistance of the sulfonated polyphenylene sulfide membrane.

[0055] Comparing the highly durable diaphragms P1-P4 prepared in Examples 1-4 with the highly durable diaphragm P5 prepared in Example 5, it can be seen that although the sulfonate shedding ratio and the reduction in surface oxygen content of the highly durable diaphragms P5 prepared in Example 5 after 24 hours of Fenton treatment are lower than those of the highly durable diaphragms P1-P4 prepared in Examples 1-4 after 24 hours of Fenton treatment, and its longitudinal breaking strength is significantly higher than that of the diaphragms P1-P4 prepared in Examples 1-4, the sulfonate shedding ratio and the reduction in surface oxygen content of the diaphragms P1-P4 prepared in Examples 1-4 after 24 hours of Fenton treatment are lower than those of the diaphragms P1-P4 prepared in Examples 1-4 after 24 hours of Fenton treatment; The obtained diaphragms P1-P4 with high durability have a longitudinal breaking strength; however, their surface resistance is significantly greater than the surface resistance of the diaphragms P1-P4 with high durability prepared in Examples 1-4; this further indicates that in the diaphragm with high durability, the higher the amount of cerium oxide attached to the sulfonated polyphenylene sulfide diaphragm, the better. A higher amount of cerium oxide attached will seriously hinder the conduction of protons, resulting in a significant increase in the resistance of the diaphragm with high durability; therefore, the amount of cerium oxide attached to the sulfonated polyphenylene sulfide diaphragm is preferably not more than 10% of the mass of the sulfonated polyphenylene sulfide diaphragm itself. Similarly, by comparing the sulfonated polyphenylene sulfide membrane Q1 in Comparative Example 1, the highly durable membranes P1-P4 prepared in Examples 1-4, and the highly durable membrane P6 prepared in Example 6, it can be seen that in the highly durable membrane, when the amount of cerium oxide attached to the sulfonated polyphenylene sulfide membrane is only 0.05% of the mass of the sulfonated polyphenylene sulfide membrane itself, the various performances of the highly durable membrane are not improved; this further indicates that in the highly durable membrane, the amount of cerium oxide attached to the sulfonated polyphenylene sulfide membrane cannot be too low, that is, the amount of cerium oxide attached to the sulfonated polyphenylene sulfide membrane is preferably not less than 0.1% of the mass of the sulfonated polyphenylene sulfide membrane.

[0056] Comparing the highly durable diaphragm P1 prepared in Example 1, the highly durable diaphragm P2 prepared in Example 2, and the highly durable diaphragm P3 prepared in Example 3, it can be seen that increasing the amount of cerium oxide attached to the sulfonated polyphenylene sulfide diaphragm can significantly reduce the sulfonate shedding rate and the reduction in surface oxygen content of the highly durable diaphragm after 24 hours of Fenton treatment, and can significantly improve the breaking strength of the highly durable diaphragm, as well as its wear resistance and water flow impact resistance. Comparing the highly durable diaphragm P4 prepared in Example 4 with the highly durable diaphragm P3 prepared in Example 3, it can be seen that the highly durable diaphragm P4 prepared in Example 4 is only slightly better than the highly durable diaphragm P3 prepared in Example 3 in all aspects of performance. This further demonstrates that when sodium tripolyphosphate is used as the surfactant, the highly durable diaphragm prepared has superior performance in all aspects. At the same time, through a large number of experimental studies, it was found and verified that surfactants containing Na and P elements such as sodium tripolyphosphate and sodium pyrophosphate are more compatible with polyphenylene sulfide fiber membranes; and surfactants containing Na and P elements can form a symbiotic crystal containing Na, P, and Ce together with cerium, which can better enable the highly durable membrane to achieve the decomposition effect of free radicals.

[0057] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and they are not intended to limit the scope of protection of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present invention.

Claims

1. A method for preparing a highly durable diaphragm, characterized in that: The following steps are involved: S1. Dissolving hydrated cerium nitrate in deionized water, then sequentially adding a surfactant and a gelling agent to the deionized water and stirring uniformly to form a cerium-containing solution; wherein the gelling agent is any one or more of an organic acid, a hydroxyl- or carbonyl-containing organic compound, and ammonia water; The surfactant is any one or more of a sodium salt surfactant, a sulfate ester surfactant, and an organic alcohol surfactant; S2, adjusting the pH value of the cerium-containing solution to a range of 0.5-5, and then increasing the temperature of the cerium-containing solution to perform a gel-forming reaction to prepare a cerium-containing sol; S3. Immerse the sulfonated polyphenylene sulfide membrane in a cerium-containing sol several times to make the average glue content on the sulfonated polyphenylene sulfide membrane 40%-80%. Then, place the sulfonated polyphenylene sulfide membrane in a heating device for a step-by-step temperature drying treatment. After the treatment is completed, a membrane with high durability is obtained; wherein the membrane with high durability includes the sulfonated polyphenylene sulfide membrane and cerium oxide attached to the sulfonated polyphenylene sulfide membrane.

2. The method for preparing a highly durable diaphragm according to claim 1, wherein: In the highly durable separator, the attached amount of the cerium oxide is 0.1% to 10% of the weight of the sulfonated polyphenylene sulfide separator.

3. The method for preparing a highly durable diaphragm according to claim 2, wherein: In the cerium-containing solution, the mass ratio of the hydrated cerium nitrate, the gelling agent, the surfactant and the deionized water is (0.01-0.3):(0.01-0.45):(0.0001-0.01):

1.

4. The method for preparing a highly durable diaphragm according to claim 2, wherein: The organic acid is any one or more of oxalic acid, citric acid, malic acid, and tartaric acid; the hydroxyl- or carbonyl-containing organic compound is any one or more of ethylene glycol, polyethylene glycol, polyvinyl pyrrolidone, and chitosan.

5. The method for preparing a highly durable diaphragm according to claim 4, wherein: The gelling agent is an organic acid; the organic acid is citric acid.

6. The method for preparing a highly durable diaphragm according to claim 2, wherein: The sodium salt active agent is any one or more of sodium tripolyphosphate, sodium pyrophosphate, sodium hexametaphosphate, trisodium phosphate, sodium carbonate, sodium dodecylbenzenesulfonate, sodium lauryl sulfate, and sodium octylsulfonate; The sulfate active agent is fatty alcohol polyoxyethylene ether sulfate and / or dodecyl polyoxyethylene ether sulfate; The organic alcohol active agent is any one or more of ethanol, isopropanol, ethylene glycol, and propylene glycol.

7. The method for preparing a highly durable diaphragm according to claim 6, wherein: The surfactant is a sodium salt active agent; the sodium salt active agent is sodium tripolyphosphate and / or sodium pyrophosphate.

8. The method for preparing a highly durable diaphragm according to claim 2, wherein: In step S2, the reaction temperature of the gelling reaction is 40-90° C., and the reaction time is 0.5-50 h; The step-by-step drying process includes: a first-stage drying process at 70-100° C. and a baking process at 120-200° C.

9. A diaphragm with high durability, characterized in that The preparation method is described in any one of claims 1 to 8.

10. Use of the highly durable diaphragm according to claim 9, characterized in that: Including the application as a diaphragm for water electrolysis hydrogen production in water electrolysis hydrogen production equipment.

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