High-temperature-resistant lubricant for elastomer sealing element of hydrogen injector or compressor
By preparing a high-temperature resistant lubricant containing high-viscosity synthetic oil, lithium soap, 12-hydroxystearic acid and calcium hydroxide thickener, and nano-clay, the problem of traditional lubricants failing in high-temperature hydrogen environments has been solved, achieving long-term effective sealing of seals and improving the safety and efficiency of hydrogen energy equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG UNIV
- Filing Date
- 2026-01-29
- Publication Date
- 2026-04-10
AI Technical Summary
Traditional lubricants have poor thermal stability and insufficient compatibility with elastomers in high-temperature hydrogen environments, leading to seal failure and affecting the safety and efficiency of hydrogen energy equipment.
This high-temperature lubricant formulation uses high-viscosity synthetic or mineral oil as the base oil, combined with lithium soap, 12-hydroxystearic acid and calcium hydroxide as thickeners, butylated hydroxytoluene as an antioxidant, and nano-clay as a heat stabilizer. It is prepared through a specific process to ensure stability and compatibility with elastomers at high temperatures.
It remains stable in high-temperature environments of 200~250℃, extends the life of seals, prevents equipment leakage, and improves the safety and efficiency of equipment operation.
Smart Images
Figure CN121825637A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of lubricants, in particular to a high-temperature-resistant lubricant for hydrogen injector or compressor elastomer seals. BACKGROUND
[0002] Under the trend of global energy structure transformation towards clean and low-carbon, green hydrogen, as a clean energy produced by water electrolysis of renewable energy, can achieve zero emission in use, and has become a key energy carrier to achieve global climate goals. Its application in fuel cells, industrial hydrogenation, transportation and other fields is continuously expanding, and a complete hydrogen value chain covering production, storage, transportation and use has been built. In the terminal application link of the hydrogen value chain, hydrogen fuel injectors and hydrogen compressors as core equipment, their stable operation directly determines the efficiency and safety of hydrogen energy systems. The sealing parts and threaded connections in such equipment are exposed to hydrogen environment for a long time, and need to withstand high temperature working conditions. The continuous loading end working temperature of the compressor and the hydrogen injector at the gas station is usually 100-120℃, and under extreme conditions it can reach 200-250℃.
[0003] Such application scenarios have multiple stringent requirements for lubricants: first, they must be resistant to hydrogen and have no pollutants to avoid affecting the performance of core components such as fuel cells; second, they must be well compatible with substrates such as elastomer seals and cannot induce hydrogen embrittlement; third, they must maintain stable performance in high-temperature environments to prevent lubrication failure due to thermal aging. However, in the prior art, traditional elastomer seals are prone to failure due to thermal aging in high-temperature environments. High temperatures can accelerate the wear of elastomers, significantly shortening the service life of the seals. The drop point and thermal stability of conventional industrial high-temperature-resistant lubricants cannot meet the use requirements of high-temperature hydrogen environments. They are prone to melting and loss at high temperatures, causing the elastomer seals to lose protection and triggering safety hazards such as equipment leakage and failure. Therefore, developing a high-temperature-resistant lubricant that is compatible with elastomers and can effectively prolong the service life of the seals in high-temperature hydrogen environments has become a technical problem to be solved in the current hydrogen energy equipment field. SUMMARY
[0004] The purpose of the present application is to provide a high-temperature-resistant lubricant for hydrogen injector or compressor elastomer seals, to solve the problems of poor thermal stability, insufficient elastomer compatibility and poor sealing protection effect of traditional lubricants in high-temperature hydrogen environments, to realize long-term effective sealing of elastomer seals in high-temperature environments, to prolong their service life, and to improve the safety and efficiency of hydrogen energy equipment operation.
[0005] To achieve the above objectives, the present invention provides a high-temperature resistant lubricant for elastomer seals of hydrogen injectors or compressors. The high-temperature resistant lubricant comprises, by weight percentage, 75-85% base oil, 10-20% thickener, and 1-10% additives. The base oil includes high-viscosity synthetic oil or mineral oil, and the additives include one of antioxidants, rust inhibitors, extreme pressure agents, and nano-clays.
[0006] The high-temperature resistant lubricant of the present invention has a dropping point of not less than 196°C and an initial decomposition temperature of not less than 345°C. It is suitable for high-temperature hydrogen environments of 100~250°C and is compatible with elastomeric seals in hydrogen fuel injectors and compressors, and does not promote hydrogen embrittlement.
[0007] Preferably, the base oil is a polyalkylene glycol base oil, which has excellent hydrogen resistance and high-temperature stability.
[0008] Preferably, the thickener is a compound system of lithium soap, 12-hydroxystearic acid, and calcium hydroxide. The lithium soap is lithium 12-hydroxystearate obtained by reacting lithium hydroxide with 12-hydroxystearic acid. The synergistic effect of lithium soap, 12-hydroxystearic acid, and calcium hydroxide can maintain a stable colloidal structure of the high-temperature lubricant at high temperatures, avoiding stratification or runoff.
[0009] Preferably, the antioxidant is butylated hydroxytoluene, which can inhibit the oxidative degradation of high-temperature lubricants at high temperatures.
[0010] Preferably, the nanoclay is 10A / 7A halloysite nanotube nanoclay or chlorite nanoclay, which can improve the thermal stability and adhesion of high-temperature lubricants.
[0011] Preferably, the preparation method of the high-temperature resistant lubricant includes the following steps: S1. Prepare lithium hydroxide solution; S2. At room temperature, pour a portion of the base oil into a mixer, add 12-hydroxystearic acid and calcium hydroxide while stirring, heat, add the lithium hydroxide solution from S1, and continue stirring to obtain mixture one; S3. Heat mixture one to 145-155℃, add the remaining base oil and antioxidant and keep for 0.5-1.5h, then heat to 158-165℃ and keep for 0.5-1.5h, and finally cool to 55-65℃ under stirring to obtain mixture two. S4. After taking out the mixture, grind it, and then add nano clay during the grinding process. After grinding, place it in a mixer and stir and degas it under vacuum to obtain a high-temperature resistant lubricant.
[0012] Preferably, in step S1, lithium hydroxide monohydrate is dissolved in deionized water and stirred until completely dissolved to prepare a lithium hydroxide solution with a mass concentration of 10%, ensuring that the solution is uniform and free of undissolved particles, and avoiding local unevenness in subsequent reactions.
[0013] Preferably, in S2, a portion of the base oil is 40% of the total mass of the base oil, and the lithium hydroxide solution of S1 is added after heating to 80°C.
[0014] Preferably, in S3, the mixture is heated to 150°C, the remaining base oil and antioxidant are added and kept for 1.0 h, then heated to 160°C and kept for 1.0 h, and finally cooled to 60°C under stirring.
[0015] Preferably, the application method of the high-temperature resistant lubricant is as follows: it is suitable for static elastomeric seals in hydrogen fuel injectors and compressors; clean the surface of the elastomeric seal before use; apply the high-temperature resistant lubricant evenly to the surface of the elastomeric seal and the sealing surface in contact with the equipment using an application tool or by hand while wearing clean gloves, with a coating thickness of not less than 1 mm, ensuring that the elastomeric seal is completely covered by the high-temperature resistant lubricant without any omissions or areas that are too thin; during equipment operation, check the condition of the high-temperature resistant lubricant every 150-200 hours, and replenish it promptly if there is any loss, drying, or local damage; after the equipment is shut down, disassemble and inspect the elastomeric seal. If the high-temperature resistant lubricant shows signs of aging, discoloration, clumping, or abnormal compatibility with the elastomeric seal, thoroughly remove the old lubricant, clean the seal again, and apply new high-temperature resistant lubricant.
[0016] Therefore, the present invention employs the above-mentioned high-temperature resistant lubricant for hydrogen injector or compressor elastomer seals, which has the following beneficial effects: (1) The dropping point of the high temperature resistant lubricant of the present invention can reach up to 205℃ and the initial decomposition temperature can reach up to 370.5℃. It can maintain stable physical properties and lubrication effect in extreme high temperature environments of 200~250℃, and avoid failure of elastomer seals due to melting and loss of the high temperature resistant lubricant. (2) The present invention effectively delays the thermal aging and wear of elastomers through the synergistic effect of nano clay and antioxidants. After high temperature aging test, the surface of the elastomer can still remain intact, significantly extending the service life of the seal and reducing equipment maintenance costs. (3) The high-temperature resistant lubricant of the present invention has strong hydrogen resistance and no pollutants, good compatibility with elastomeric seals, does not induce hydrogen embrittlement, meets the usage requirements of hydrogen fuel injectors, compressors and other hydrogen energy equipment, and ensures the safe operation of equipment; (4) The formulation components of this invention are readily available, the preparation process is controllable, it is suitable for industrial mass production, and has broad application prospects.
[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the high-temperature resistant lubricant of the present invention used in the elastomer seal of a hydrogen injector; Figure 2 This is a schematic diagram of the high-temperature resistant lubricant of the present invention used in compressor elastomer seals; Figure 3 This is a comparison chart of the thermogravimetric analysis (TGA) curves of the comparative industrial lubricating grease IG of this invention and the high-temperature resistant lubricants NG-1 and NG-2 of Examples 2-3. Figure 3 In the figure, 'a' represents the thermogravimetric analysis (TGA) curve of industrial lubricating grease IG; Figure 3 In the figure, b is the thermogravimetric analysis (TGA) curve of the high-temperature lubricant NG-1. Figure 3 In the figure, 'c' represents the thermogravimetric analysis (TGA) curve of the high-temperature lubricant NG-2. Figure 4 These are SEM images of the elastic seals treated with different lubricants according to the present invention. Figure 4 In the image, 'a' represents an SEM image of an elastic seal that has not been treated with lubricant or aged. Figure 4 In the image, b is a SEM image of an elastic seal that has been aged at 150°C for 5 days without lubricant treatment. Figure 4 In the image, c represents the SEM image of an elastic seal that has been treated with industrial grease IG and aged at 150°C for 5 days. Figure 4 In the image, 'd' represents the SEM image of an elastic seal that has been treated with the high-temperature lubricant NG-1 and aged at 150°C for 5 days. Figure 4 In the figure, 'e' is a SEM image of an elastic seal that has been treated with high-temperature lubricant NG-2 and aged at 150°C for 5 days.
[0019] Figure label: 1. Hydrogen fuel injector; 2. Hydrogen compressor; 3. Elastomer seal. Detailed Implementation
[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments. Unless otherwise defined, the technical or scientific terms used in this invention should be understood in their ordinary sense by those skilled in the art. The features mentioned above or in the specific examples mentioned in this invention can be combined arbitrarily, and these specific embodiments are only used to illustrate the invention and are not intended to limit the scope of the invention.
[0021] Example 1 This invention provides the composition of a high-temperature resistant lubricant for hydrogen injector or compressor elastomer seals, comprising, by mass percentage: 80% polyalkylene glycol base oil, 10% lithium soap, 5% 12-hydroxystearic acid, 1% calcium hydroxide, 2% butylated hydroxytoluene, and 2% chlorite nanoclay.
[0022] Example 2 This embodiment provides a method for preparing a high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors. All raw materials and quantities are the same as in Example 1, and the method includes the following steps: S1. Dissolve lithium hydroxide monohydrate in deionized water and stir until completely dissolved to prepare a lithium hydroxide solution with a mass concentration of 10%.
[0023] S2. At room temperature, pour 40% of the total mass of polyalkylene glycol base oil into a mixer, add 12-hydroxystearic acid and calcium hydroxide while stirring, heat to 80°C, add the lithium hydroxide solution from S1, and continue stirring to obtain mixture one.
[0024] S3. Heat mixture one to 150°C, add the remaining polyalkylene glycol base oil and butylated hydroxytoluene, stir until homogeneous and maintain for 1.0 h, then heat to 160°C and maintain for 1.0 h with stirring, and finally cool to 60°C with stirring to obtain mixture two.
[0025] S4. Transfer the mixture to a three-cylinder mill for grinding. Then, add chlorite nano-clay during the grinding process. After grinding, place it in a mixer and stir and degas it under vacuum to obtain a high-temperature resistant lubricant, denoted as NG-1.
[0026] Example 3 The difference from Example 2 is that the nanoclay used in step S2 is 10A / 7A halloysite nanotube nanoclay, while the rest is the same as in Example 2. The resulting high-temperature resistant lubricant is denoted as NG-2.
[0027] Example 4 This embodiment provides a method for using a high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors, such as... Figures 1 to 2As shown, the high-temperature resistant lubricant is suitable for the elastomeric seal 3 in the hydrogen fuel injector 1 and the hydrogen compressor 2. The elastomeric seal 3 is an O-ring, gasket, or dust cover. Its application method includes the following steps: Before use, clean the surface of the elastomeric seal 3 to remove oil, dust, and other impurities; using a spreading tool or wearing clean gloves, manually and evenly apply the high-temperature resistant lubricant prepared in Example 2 to the surface of the elastomeric seal 3 and the sealing surface in contact with the equipment, with a coating thickness of not less than 1 mm, ensuring that the elastomeric seal is completely covered by the high-temperature resistant lubricant without any omissions or areas that are too thin; during equipment operation, check the condition of the high-temperature resistant lubricant every 150-200 hours. If the high-temperature resistant lubricant is lost, dried out, or partially damaged, replenish it promptly; after the equipment is shut down, disassemble and inspect the elastomeric seal 3. If the high-temperature resistant lubricant shows signs of aging, discoloration, clumping, or abnormal compatibility with the elastomeric seal 3, thoroughly remove the old lubricant, clean the seal again, and apply new high-temperature resistant lubricant.
[0028] Comparative Example It is a standard industrial lubricating grease, IG.
[0029] Performance testing: The high-temperature resistant lubricants NG-1 and NG-2 of this invention, along with industrial grease IG, were tested for their dropping points using a dropping point tester (SYD-3498-Ⅰ) according to ASTM-D566. The initial decomposition temperature (TGA) was tested under a nitrogen atmosphere at a temperature range of 25-600°C with a heating rate of 10°C / min. The high-temperature resistant lubricants NG-1 and NG-2, along with industrial grease IG, were uniformly applied (1 mm thickness) to the surface of the elastic seal of a hydrogen fuel injector. After assembly, the injector was placed in a high-temperature environment of 150°C for 5 days of aging. After operation, the elastic seal was disassembled and inspected. The results are shown in Table 1 and... Figures 3 to 4 .
[0030] Table 1 Performance test results of different lubricants
[0031] From Table 1 and Figure 3 As shown, the TGA of the high-temperature resistant lubricant prepared by this invention is significantly higher than that of conventional industrial lubricating grease IG, and NG-2 reaches as high as 370.5℃, exhibiting excellent thermal stability.
[0032] From Table 1 and Figure 4 As shown, the elastomer exhibits severe degradation in the absence of grease. In comparison, rubber ring seals treated with IG and NG-1 show better resistance, but still exhibit some degradation. Notably, rubber ring seals treated with NG-2 retain an undamaged elastomer surface even after high-temperature aging.
[0033] Therefore, the high-temperature resistant lubricant used in the present invention for the elastomer seals of hydrogen injectors or compressors is significantly superior to conventional industrial greases in terms of dropping point, thermal stability and elastomer protection effect, and can better meet the needs of use in high-temperature hydrogen environments.
[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.
Claims
1. A high-temperature resistant lubricant for use in elastomer seals of hydrogen injectors or compressors, characterized in that: High-temperature resistant lubricants, by weight percentage, consist of 75-85% base oil, 10-20% thickener, and 1-10% additives. The base oil includes high-viscosity synthetic oil or mineral oil, and the additives include one of the following: antioxidant, rust inhibitor, extreme pressure agent, and nano clay.
2. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 1, characterized in that: The base oil is a polyalkylene glycol base oil.
3. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 1, characterized in that: The thickener is a compound system of lithium soap, 12-hydroxystearic acid and calcium hydroxide.
4. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 1, characterized in that: The antioxidant is butylated hydroxytoluene.
5. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 1, characterized in that: The nanoclay is either 10A / 7A halloysite nanotube nanoclay or chlorite nanoclay.
6. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 3, characterized in that: The preparation method of high-temperature resistant lubricant includes the following steps: S1. Prepare lithium hydroxide solution; S2. At room temperature, pour a portion of the base oil into a mixer, add 12-hydroxystearic acid and calcium hydroxide while stirring, heat, add the lithium hydroxide solution from S1, and continue stirring to obtain mixture one; S3. Heat mixture one to 145-155℃, add the remaining base oil and antioxidant and keep for 0.5-1.5h, then heat to 158-165℃ and keep for 0.5-1.5h, and finally cool to 55-65℃ under stirring to obtain mixture two. S4. After taking out the mixture, grind it, and then add nano clay during the grinding process. After grinding, place it in a mixer and stir and degas it under vacuum to obtain a high-temperature resistant lubricant.
7. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 1, characterized in that: In S1, lithium hydroxide monohydrate is dissolved in deionized water and stirred until completely dissolved to prepare a lithium hydroxide solution with a mass concentration of 10%.
8. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 1, characterized in that: In S2, a portion of the base oil, comprising 40% of the total mass of the base oil, is added to the lithium hydroxide solution of S1 after being heated to 80°C.
9. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 1, characterized in that: In S3, the mixture is heated to 150°C, the remaining base oil and antioxidant are added and kept for 1.0 h, then heated to 160°C and kept for 1.0 h, and finally cooled to 60°C under stirring.
10. The high-temperature resistant lubricant for elastomeric seals of hydrogen injectors or compressors according to claim 1, characterized in that: The application method for high-temperature resistant lubricant is as follows: It is suitable for static elastomeric seals in hydrogen fuel injectors and compressors. Before use, clean the surface of the elastomeric seal. Using a spreading tool or wearing clean gloves, manually apply the high-temperature resistant lubricant evenly to the surface of the elastomeric seal and the sealing surface in contact with the equipment. The application thickness should not be less than 1 mm, ensuring that the elastomeric seal is completely covered by the high-temperature resistant lubricant without any omissions or areas that are too thin. During equipment operation, check the condition of the high-temperature resistant lubricant every 150-200 hours. If the high-temperature resistant lubricant is lost, dried out, or partially damaged, replenish it promptly. After the equipment is shut down, disassemble and inspect the elastomeric seal. If the high-temperature resistant lubricant shows signs of aging, discoloration, clumping, or abnormal compatibility with the elastomeric seal, thoroughly remove the old lubricant, clean the seal again, and apply new high-temperature resistant lubricant.