Ion exchange membrane treatment process for electrocatalytic synthesis ammonia test and membrane preservation device for shielding ammonia pollution
By pretreating the ion exchange membrane and using a nested inert gas-hydration barrier ammonia contaminated membrane storage device, the inaccuracy of test caused by ammonia contamination in electrocatalytic synthesis ammonia testing is solved, and the effect of simplifying pretreatment and reducing costs is achieved.
Patent Information
- Application Number
- CN202510625997.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-15
- Publication Date
- 2025-08-15
AI Technical Summary
In the existing electrocatalytic synthesis ammonia test system, the ion exchange membrane is susceptible to ammonia contamination, resulting in inaccurate test results, and the existing pretreatment methods are time-consuming and economically cost-effective.
The ion exchange membrane was batch pretreated using deionized water, hydrogen peroxide and sulfuric acid solutions, and stored in a nested inert gas-hydration barrier ammonia contaminated membrane storage device. Before the test, the ammonia content was reduced by ultrasonic treatment of sulfuric acid and deionized water.
The pretreatment process is simplified, the ammonia contamination in the ion exchange membrane is reduced, the accuracy of electrocatalytic synthesis ammonia test is improved, and the time and economic costs are reduced.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the field of electrocatalytic ammonia synthesis, including but not limited to electrocatalytic nitrogen reduction to ammonia synthesis, electrocatalytic nitrate reduction to ammonia synthesis, electrocatalytic nitrogen oxide reduction to ammonia synthesis, etc., and in particular relates to an ion exchange membrane treatment process for electrocatalytic ammonia synthesis testing and a membrane preservation device based on a nested inert gas-hydration barrier ammonia contamination. Background Art
[0002] Currently, industrial ammonia synthesis relies primarily on the energy-intensive Haber-Bosch process, which produces over 90% of global ammonia production annually. This process also generates 300 million metric tons of carbon dioxide annually and consumes 1% of global electricity generation. Electrocatalytic ammonia synthesis, a technology that uses electricity to directly convert nitrogen, nitrates, nitrogen oxides, and other gases into ammonia with water, holds great significance for integrating renewable energy and enabling distributed ammonia production. However, the ubiquitous presence of ammonia in the environment poses significant challenges to the quantification of ammonia in electrocatalytic nitrogen reduction testing systems. This significantly impacts the accurate performance evaluation of electrocatalytic ammonia synthesis catalysts and limits their efficient development.
[0003] The laboratory testing system for electrocatalytic ammonia synthesis consists of an H-type electrolytic cell, electrodes, and a diaphragm (primarily an ion exchange membrane). While the H-type electrolytic cell and electrodes can be effectively reduced in ammonia content through repeated washing, there remains no simple, effective method for the diaphragm. Conventional pretreatment methods and storage of ion exchange membranes in conventional storage devices can lead to ammonia accumulation in the storage device due to environmental ammonia contamination, resulting in high levels of ammonia. This seriously impacts the accuracy of electrocatalytic ammonia synthesis catalyst performance testing and evaluation. Reducing ammonia contamination in the diaphragm is the only option, requiring frequent pretreatment, which is both time-consuming and costly.
[0004] Therefore, the development of a simple, easy-to-use and highly operational ion exchange membrane treatment process for electrocatalytic ammonia synthesis testing and a membrane preservation device based on nested inert gas-hydration barrier ammonia contamination is of great significance for reducing ammonia contamination in proton exchange membranes and improving the accuracy of ammonia quantification experimental results in electrocatalytic ammonia synthesis test systems. Summary of the Invention
[0005] To address the aforementioned issues in the prior art, the present invention addresses the inaccurate test results often caused by ammonia contamination in ion exchange membranes in electrocatalytic ammonia synthesis testing systems. The present invention provides an ion exchange membrane treatment process for electrocatalytic ammonia synthesis testing and a membrane storage device based on a nested inert gas-hydration barrier to prevent ammonia contamination. This treatment process, specifically for electrocatalytic nitrogen reduction testing systems, where test results are susceptible to ammonia contamination, stores the pretreated ion exchange membrane in a membrane storage device based on a nested inert gas-hydration barrier to prevent ammonia contamination. Each time the ion exchange membrane is removed from the membrane storage device, it is ultrasonically treated in sulfuric acid and deionized water to rapidly desorb ammonia adsorbed in the ion exchange membrane, effectively reducing ammonia contamination in the ion exchange membrane. This process is applicable to electrochemical ammonia synthesis tests such as electrocatalytic nitrogen reduction, electrocatalytic nitrate reduction, and electrocatalytic nitrogen oxide reduction.
[0006] More specifically, the present invention provides an ion exchange membrane treatment process for electrocatalytic ammonia synthesis testing, comprising the following steps:
[0007] (1) heat-treating the ion exchange membrane in a sealed container containing deionized water, hydrogen peroxide, and sulfuric acid solution for a certain period of time, then immersing the heat-treated ion exchange membrane in deionized water, storing it in a membrane storage device based on a nested inert gas-hydration barrier ammonia contamination, and storing the device in a room temperature environment away from light;
[0008] (2) Before conducting the electrocatalytic ammonia synthesis test, the ion exchange membrane in step (1) is removed from the membrane storage device based on the nested inert gas-hydration barrier ammonia pollution, and ultrasonically treated in a closed container filled with sulfuric acid solution and deionized water in sequence, and the treatment is repeated multiple times before use.
[0009] In an embodiment of the above method, in step (1), the ion exchange membrane is a commercial proton exchange membrane.
[0010] In an embodiment of the above method, in step (1), the temperature of the deionized water, hydrogen peroxide and sulfuric acid solution in the heat treatment process is 20-80°C, and the heat treatment time is 1-24 hours; preferably, the temperature is 80°C, and the heat treatment time is 1 hour; preferably, the closed container refers to the same closed container.
[0011] In the embodiment of the above method, in step (1), the mass fraction of hydrogen peroxide is 5-10 wt%, and the sulfuric acid solution is 0.1-1 mol L -1 H2SO4; preferably, the mass fraction of the hydrogen peroxide solution is 5wt%, and the sulfuric acid solution is 0.5mol L -1 H2SO4.
[0012] The present invention also protects a membrane preservation device based on a nested inert gas-hydration barrier ammonia pollution, including a membrane preservation outer tank and a membrane preservation inner tank. The ion exchange membrane after heat treatment is stored in the membrane preservation inner tank containing deionized water to maintain the proton conduction of the ion exchange membrane. The membrane preservation inner tank is embedded and preserved in the membrane preservation outer tank filled with inert gas to prevent the membrane preservation inner tank from being contaminated by ammonia in the outside air.
[0013] In an embodiment of the above method, the membrane storage tank is provided with an ammonia concentration detector, an air inlet, and an air outlet.
[0014] In an embodiment of the above method, the inert gas includes one of nitrogen and argon; preferably, the inert gas is argon.
[0015] In the embodiment of the above method, in step (2), each time the ion exchange membrane is removed from the membrane protection device, inert gas must be refilled into the membrane protection outer tank through the air inlet until the ammonia concentration in the membrane protection outer tank detected by the ammonia concentration detector is less than 1 μg m -3 .
[0016] In the embodiment of the above method, in step (2), the sulfuric acid solution is 0.05-0.5 mol L -1 H2SO4; preferably, the sulfuric acid solution is 0.5 molL -1 H2SO4.
[0017] In an embodiment of the above method, in step (2), the ultrasonic treatment frequency is 20-60 KHz; preferably, the ultrasonic treatment frequency is 40 KHz.
[0018] In an embodiment of the above method, in step (2), the ultrasonic treatment time is 0.5-2 hours; preferably, the ultrasonic treatment time is 0.5 hours.
[0019] In the embodiment of the above method, the multiple cycles in step (2) refer to the cycle of "sulfuric acid solution, deionized water" in the order of 1-3 times.
[0020] In the embodiment of the above method, all sealed containers and membrane storage devices must be kept at room temperature before use at 0.5 mol / L -1 Soak in H2SO4 for 1-2 hours to remove ammonia attached to the container and the device itself.
[0021] The present invention also protects the above-mentioned treatment process or device for reducing ammonia contamination in ion exchange membranes.
[0022] The present invention also protects the use of the above-mentioned treatment process or device in electrochemical ammonia synthesis tests such as electrocatalytic nitrogen reduction, electrocatalytic nitrate reduction, and electrocatalytic nitrogen oxide reduction.
[0023] Targeting electrocatalytic ammonia synthesis testing systems, which are susceptible to inaccurate experimental results due to ammonia contamination in ion exchange membranes, the present invention uses deionized water, hydrogen peroxide, and sulfuric acid solutions to sequentially pre-treat the ion exchange membranes in batches. The membranes are then stored in a membrane storage device based on a nested inert gas-hydration barrier to prevent ammonia contamination. During testing, the membranes are ultrasonically treated with sulfuric acid and deionized water, respectively, utilizing ion exchange to produce an ion exchange membrane with ultra-low ammonia content. Compared to existing technologies, this method offers the following advantages:
[0024] 1. The treatment process of the present invention has simple procedures and is feasible for reducing ammonia contamination in ion exchange membranes. It can be widely used in electrocatalytic ammonia synthesis tests such as electrocatalytic nitrogen reduction, electrocatalytic nitrate reduction, and electrocatalytic nitrogen oxide reduction, thereby improving the accuracy of test results.
[0025] 2. The present invention's nested inert gas-hydration barrier ammonia contamination membrane storage device features a streamlined structure, effectively avoiding the complex and expensive membrane storage equipment (e.g., glove boxes) associated with conventional electrocatalytic nitrogen reduction ammonia synthesis testing. The present invention's ion exchange membrane treatment process for electrocatalytic ammonia synthesis testing and its nested inert gas-hydration barrier ammonia contamination membrane storage device can effectively reduce the time and cost associated with ion exchange membrane pretreatment prior to testing various electrochemical ammonia synthesis systems. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The following is a further explanation with reference to the accompanying drawings, comparing the ammonia content in the ion exchange membrane after conventional pretreatment and after the method of the present invention.
[0027] Figure 1 This is a schematic diagram of the structure of a membrane preservation device designed by the present invention based on a nested inert gas-hydration barrier for ammonia contamination. 1—Ammonia concentration detector; 2—Gas outlet; 3—Gas inlet; 4—Membrane protection inner tank; 5—Membrane protection outer tank.
[0028] Figure 2 The present invention adopts indigo blue color development method to conduct UV-visible absorption spectrum test curve of different ammonium chloride solutions with known concentrations. The absorbance at 655nm corresponds to NH4 + concentration.
[0029] Figure 3 The ammonia standard curve of the present invention is used to calculate the NH4 in the liquid + concentration.
[0030] Figure 4The relationship between the ammonia concentration in the proton exchange membrane stored in a sealed ordinary beaker (Example 1) and the proton exchange membrane stored in the nested inert gas-hydration barrier ammonia contamination membrane storage device designed by the present invention (Example 2) as a function of storage days is shown. The ammonia concentration is detected by the indophenol blue method at 0.1 mol L -1 The UV-visible absorption spectrum test curve of the solution obtained after sealing and soaking in Na2SO4 for 2 hours was obtained.
[0031] Figure 5 is 0.1 mol / L -1 The UV-visible absorption spectrum test curve of the blank solution of Na2SO4, the conventional pre-treated proton exchange membrane (Example 3) at 0.1 mol L -1 The UV-visible absorption spectrum test curve of the solution obtained after sealing and soaking in Na2SO4 for 2 hours shows that the proton exchange membrane treated by the method of the present invention (Example 4) has a high absorption rate in 0.1 mol L -1 UV-visible absorption spectrum test curve of the solution obtained after sealed and immersed in Na2SO4 for 2 hours.
[0032] Figure 6 is 0.1 mol L -1 The ammonia concentration in the Na2SO4 blank solution was 0.1 mol L -1 The ammonia concentration of the solution obtained by sealing and soaking in Na2SO4 for 2 hours is 0.1 mol L -1 The ammonia concentration of the solution obtained after sealing and soaking in Na2SO4 for 2 hours.
[0033] Figure 7 The graph shows the Fourier transform infrared spectra of a conventionally pretreated proton exchange membrane and a proton exchange membrane treated by the method of the present invention before the electrocatalytic ammonia synthesis test. DETAILED DESCRIPTION
[0034] In order to make the purpose, technical solutions and beneficial effects of the present invention more clear, the present invention is described with the following specific embodiments, but the present invention is by no means limited to these examples.
[0035] The ammonia concentration in the solution is determined by a salicylic acid-modified indophenol blue colorimetric method, the steps of which include:
[0036] Step (1): Pipette 2 mL of the solution to be tested;
[0037] Step (2): Add 2 mL of 1 mol L -1 a mixed solution consisting of NaOH, sodium citrate (5 wt %), and salicylic acid (5 wt %);
[0038] Step (3): Add 1 mL of 0.05 mol L -1 Sodium hypochlorite solution;
[0039] Step (4): Add 200 μL of sodium nitroprusside solution (1 wt%) to the solution treated in step (3).
[0040] Step (5): Shake well and keep away from light for 2 hours.
[0041] The absorbance value between 750-550 nm was then measured using a UV-visible spectrophotometer, the absorbance peak of the sample near 650 nm was observed, and the ammonia concentration in the test solution was determined using a standard curve.
[0042] Standard curve determination: The standard curve is drawn by recording the absorbance intensity of NH4Cl at different concentrations near 655nm. To ensure data accuracy, the fitting variance of the standard curve is controlled to be above 0.999.
[0043] Example 1:
[0044] This example uses Nafion TM N117 perfluorosulfonic acid proton exchange membrane, membrane area 2×2cm 2 All sealed containers and storage devices were kept at room temperature before use at 0.5 mol L -1 The membranes were immersed in H2SO4 for 1 hour. In the following step (2) of detecting the ammonia content in the membrane, three membranes were used for parallel testing.
[0045] (1) Membrane treatment process:
[0046] The proton exchange membrane was placed in a mixture of 80℃ deionized water, 80℃ 5wt% H2O2, 80℃ 0.5mol L - 1 The membrane was sealed and heat-treated in a beaker of H2SO4 solution for 2 h; then the pretreated membrane was sealed and stored in a 250 mL ordinary beaker filled with deionized water at room temperature in the dark.
[0047] (2) Detection of ammonia content in the membrane:
[0048] Take a piece of proton exchange membrane from a common beaker every day and place it in a container containing 40mL of 0.1mol L -1 Place the solution in a beaker containing 0.1 mol / L Na2SO4 in a sealed container and allow to stand for 2 hours. Then transfer 2 mL of the solution to be tested and 2 mL of the original 0.1 mol / L -1 Na2SO4 solution was used as blank control, and ammonia content was detected by indigo blue colorimetry.
[0049] Example 2:
[0050] This example uses Nafion TM N117 perfluorosulfonic acid proton exchange membrane, membrane area 2×2cm 2 All sealed containers and storage devices were kept at 0.5 mol L -1 The membrane was treated in H2SO4 for 1 hour. In the following step (2) of detecting the ammonia content in the membrane, three membranes were used for parallel experimental detection.
[0051] (1) Membrane treatment process:
[0052] The proton exchange membrane was placed in a mixture of 80℃ deionized water, 80℃ 5wt% H2O2, 80℃ 0.5mol L - 1 The pretreated membrane was sealed in a beaker of H2SO4 solution and heat treated for 2 hours; Figure 1 The membrane storage device designed by the present invention based on the nested inert gas-hydration barrier ammonia pollution is sealed and stored at room temperature away from light, and the inert gas in the device is argon.
[0053] (2) Detection of ammonia content in the membrane:
[0054] Every day from Figure 1 Take a piece of proton exchange membrane from the membrane storage device shown in the figure and place it in a container containing 40mL of 0.1molL -1 Place the solution in a beaker containing 0.1 mol L Na2SO4 in a sealed container and allow to stand for 2 hours. Then transfer 2 mL of the solution to be tested and 2 mL of the original 0.1 mol L -1 Na2SO4 solution was used as blank control, and ammonia content was detected by indigo blue colorimetry.
[0055] Example 3:
[0056] This example uses Nafion TM N117 perfluorosulfonic acid proton exchange membrane, membrane area 2×2cm 2 All sealed containers and membrane storage devices were kept at 0.5 mol L -1 Treated in H2SO4 for 1 hour; in the following step (2) of detecting the ammonia content in the membrane, three membranes were used for parallel experimental detection.
[0057] (1) Membrane treatment process:
[0058] The proton exchange membrane was placed in a mixture of 80℃ deionized water, 80℃ 5wt% H2O2, 80℃ 0.5mol L - 1The pretreated membrane was sealed in a beaker of H2SO4 solution and heat treated for 2 hours; Figure 1 The membrane storage device designed by the present invention based on the nested inert gas-hydration barrier ammonia pollution is sealed and stored at room temperature away from light, and the inert gas in the device is argon.
[0059] (2) Detection of ammonia content in the membrane:
[0060] From Figure 1 Take a piece of proton exchange membrane from the membrane storage device shown in the figure and place it in a container containing 40 mL of 0.1 mol L - 1 Place the solution in a beaker containing 0.1 mol L Na2SO4 in a sealed container and allow to stand for 2 hours. Then transfer 2 mL of the solution to be tested and 2 mL of the original 0.1 mol L - 1 Na2SO4 solution was used as blank control, and ammonia content was detected by indigo blue colorimetry.
[0061] (3) Determination of ammonia in the membrane:
[0062] From Figure 1 A piece of proton exchange membrane was taken from the membrane storage device shown and subjected to Fourier transform infrared spectroscopy testing.
[0063] Example 4:
[0064] This example uses Nafion TM N117 perfluorosulfonic acid proton exchange membrane, membrane area 2×2cm 2 All containers and devices were kept at 0.5 mol L -1 Treated in H2SO4 for 1 hour; in the following step (2) of detecting the ammonia content in the membrane, three membranes were used for parallel experimental detection.
[0065] (1) Membrane treatment process:
[0066] The proton exchange membrane was placed in a mixture of 80℃ deionized water, 80℃ 5wt% H2O2, 80℃ 0.5mol L - 1 The membrane was sealed and heat treated in a beaker of H2SO4 solution for 2 hours. Figure 1 The membrane storage device designed by the present invention based on the nested inert gas-hydration barrier ammonia pollution is sealed and stored at room temperature away from light, and the inert gas in the device is argon.
[0067] Remove the proton exchange membrane from the membrane protection device and place it in a container filled with 0.5 mol L -1Ultrasonic treatment was carried out in a sealed container of H2SO4 and deionized water in turn, and the cycle was repeated once. The ultrasonic power was 40KHz and the ultrasonic time was 0.5 hours.
[0068] (2) Detection of ammonia content in the membrane:
[0069] Place the treated proton exchange membrane in a container containing 40 mL of 0.1 mol L -1 Place the solution in a beaker containing 0.1 mol L Na2SO4 in a sealed container and allow to stand for 2 hours. Then transfer 2 mL of the solution to be tested and 2 mL of the original 0.1 mol L -1 Na2SO4 solution was used as blank control, and ammonia content was detected by indigo blue colorimetry.
[0070] (3) Determination of ammonia in the membrane:
[0071] The treated proton exchange membrane was subjected to Fourier transform infrared spectroscopy test.
[0072] Figure 4 The relationship between the ammonia concentration in the proton exchange membrane stored in a common beaker and the proton exchange membrane stored in the nested inert gas-hydration barrier ammonia contamination membrane storage device designed by the present invention and the storage days is shown. The ammonia concentration is detected by the indophenol blue method at 0.1 mol L -1 The UV-visible absorption spectrum test curve of the solution obtained after sealing and soaking in Na2SO4 for 2 hours was obtained.
[0073] from Figure 4 It can be seen that compared with the proton exchange membrane sealed and stored in an ordinary beaker (Example 1), the proton exchange membrane stored in the membrane storage device based on the nested inert gas-hydration barrier ammonia pollution designed by the present invention (Example 2) can effectively reduce the contamination of the proton exchange membrane in the device by ammonia in the external air due to the physical barrier effect of its inert gas-hydration barrier, and has the ability to preserve the ion exchange membrane for electrocatalytic ammonia synthesis testing for a long time.
[0074] Figure 5 is 0.1 mol / L -1 UV-visible absorption spectrum test curve of Na2SO4 blank solution, conventional pre-treated proton exchange membrane in 0.1 mol L -1 The UV-visible absorption spectrum test curve of the solution obtained after sealing and soaking in Na2SO4 for 2 hours (Example 3), the proton exchange membrane treated by the method of the present invention in 0.1 mol L -1 UV-visible absorption spectrum test curve of the solution obtained after sealed immersion in Na2SO4 for 2 hours (Example 4).
[0075] from Figure 5It can be seen that the proton exchange membrane treated by the method of the present invention (Example 4) is - 1 After being sealed and immersed in Na2SO4 for 2 hours, the absorbance of the UV-visible absorption spectrum test curve of the obtained solution at 655nm was significantly lower than the test curve of the conventional pre-treated proton exchange membrane (Example 3) in three parallel experiments.
[0076] Figure 3 The ammonia standard curve of the present invention is used to calculate the NH4 in the liquid + concentration; Figure 6 It is the use of Figure 3 Ammonia standard curve and Figure 5 The test results show that the calculated 0.1 mol L -1 The ammonia concentration in the Na2SO4 blank solution was 0.1 mol L -1 The ammonia concentration of the solution obtained by sealing and soaking in Na2SO4 for 2 hours (Example 3) and the proton exchange membrane treated by the method of the present invention in 0.1 mol L -1 Ammonia concentration in the solution obtained after sealed immersion in Na2SO4 for 2 hours (Example 4).
[0077] from Figure 6 It can be seen that compared with the proton exchange membrane pretreated by conventional method (Example 3), the proton exchange membrane treated by the method of the present invention has a high -1 The ammonia concentration in the solution obtained after sealed immersion in Na2SO4 for 2 hours (Example 4) was significantly lower than the detection results of the conventional pretreatment of the proton exchange membrane, indicating that the method of the present invention can significantly reduce the ammonia contamination in the proton exchange membrane, improve the test accuracy of the subsequent electrocatalytic nitrogen reduction synthesis ammonia experiment, and reduce the experimental error.
[0078] Figure 7 The following are the Fourier transform infrared spectrum test curves of the conventional pre-treated proton exchange membrane before the electrocatalytic ammonia synthesis test (Example 3) and the Fourier transform infrared spectrum test curves of the proton exchange membrane treated by the method of the present invention (Example 4). Figure 7 It can be seen that the conventional pretreated proton exchange membrane and the proton exchange membrane treated by the method of the present invention show that the proton exchange membrane itself contains H3O + , CF bond, SO bond, -COC- bond, the proton exchange membrane treated by the method of the present invention (Example 4) did not detect NH4 + , while NH4 can still be detected using conventional pre-treated proton exchange membrane (Example 3) + This also shows that the method of the present invention can significantly reduce ammonia contamination in the proton exchange membrane.
[0079] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. Those skilled in the art may make various equivalent modifications or substitutions without departing from the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.
Claims
1. A membrane preservation device based on a nested inert gas-hydration barrier ammonia pollution, characterized in that It includes a membrane storage outer tank and a membrane storage inner tank. The heat-treated ion exchange membrane is stored in the membrane storage inner tank containing deionized water to maintain the proton conduction of the ion exchange membrane. The membrane storage inner tank is embedded in the membrane storage outer tank filled with inert gas to prevent the membrane storage inner tank from being contaminated by ammonia in the outside air.
2. The film storage device according to claim 1, characterized in that The membrane storage tank is provided with an ammonia concentration detector, an air inlet and an air outlet.
3. The film storage device according to claim 1, characterized in that The inert gas includes one of nitrogen and argon; preferably, the inert gas is argon.
4. An ion exchange membrane treatment process for electrocatalytic ammonia synthesis testing, characterized in that: The following steps are involved: (1) heat-treating an ion exchange membrane in a sealed container containing deionized water, hydrogen peroxide, and sulfuric acid solution for a certain period of time, then immersing the heat-treated ion exchange membrane in deionized water, storing the membrane in a membrane storage device according to any one of claims 1 to 3, and storing the membrane in a room temperature environment away from light; (2) Before conducting the electrocatalytic ammonia synthesis test, the ion exchange membrane in step (1) is removed from the membrane storage device based on the nested inert gas-hydration barrier ammonia pollution, and ultrasonically treated in a closed container filled with sulfuric acid solution and deionized water in sequence, and the treatment is repeated multiple times before use.
5. The treatment process according to claim 4, characterized in that: In step (1), the ion exchange membrane is a commercial proton exchange membrane; Furthermore, the temperature of the deionized water, hydrogen peroxide and sulfuric acid solution during the heat treatment process is 20-80°C, and the heat treatment time is 1-24 hours; preferably, the temperature is 80°C, and the heat treatment time is 1 hour; preferably, the closed container refers to the same closed container. Furthermore, in step (1), the mass fraction of hydrogen peroxide is 5-10 wt%, and the sulfuric acid solution is 0.1-1 mol L -1 H2SO4; preferably, the mass fraction of the hydrogen peroxide solution is 5wt%, and the sulfuric acid solution is 0.5mol L - 1 H2SO4.
6. The treatment process according to claim 4, characterized in that: In step (2), each time the ion exchange membrane is removed from the membrane protection device, inert gas must be refilled into the membrane protection outer tank through the air inlet until the ammonia concentration in the membrane protection outer tank detected by the ammonia concentration detector is less than 1 μg m -3 ; Furthermore, in step (2), the sulfuric acid solution is 0.05-0.5 mol L -1 H2SO4; preferably, the sulfuric acid solution is 0.5 mol L -1 H2SO4; Furthermore, in step (2), the ultrasonic treatment frequency is 20-60 KHz; preferably, the ultrasonic treatment frequency is 40 KHz; Furthermore, in step (2), the ultrasonic treatment time is 0.5-2 hours; preferably, the ultrasonic treatment time is 0.5 hours; Furthermore, the multiple cycles in step (2) refer to the cycle of "sulfuric acid solution, deionized water" for 1-3 times.
7. The treatment process according to any one of claims 4 to 6, characterized in that: All sealed containers and membrane storage devices must be heated to 0.5 mol L at room temperature before use. -1 Soak in H2SO4 for 1-2 hours to remove ammonia attached to the container and the device itself.
8. The membrane preservation device according to any one of claims 1 to 3, or the treatment process according to any one of claims 4 to 7, for reducing ammonia contamination in an ion exchange membrane.
9. Use of the membrane preservation device according to any one of claims 1 to 3, or the treatment process according to any one of claims 4 to 7, in testing an electrochemical ammonia synthesis system.
10. The use according to claim 9, characterized in that The electrochemical ammonia synthesis system includes electrocatalytic nitrogen reduction, electrocatalytic nitrate reduction, electrocatalytic nitrogen oxide reduction, etc.