Graphene-based high-performance environment-friendly lubricating oil and preparation process thereof

Abstract

This invention relates to the technical field of graphene's super-lubricating properties and discloses a graphene-based high-performance environmentally friendly lubricating oil and its preparation process, comprising: (a) 0.5-2% by weight of multilayer graphene nanosheets, the surface of which is coated with a metal oxide film of controllable thickness by atomic layer deposition technology; (b) 97-99.4% by weight of high-purity PAO synthetic oil; and (c) 0.1-1% by weight of multifunctional biodegradable additives, including novel antioxidants and anti-wear agents extracted from marine microorganisms. This invention coats the surface of graphene nanosheets with a metal oxide film by atomic layer deposition technology, enabling it to respond to temperature and pressure changes, enhancing the self-healing mechanism and stability of the lubricating oil. Furthermore, by controlling the size and surface modification of the graphene nanosheets, the lubricating oil of this invention exhibits excellent lubrication performance and anti-wear protection under high temperature, high pressure, extreme temperature, and heavy load conditions.

Description

Technical Field

[0001] This invention relates to the field of graphene super-lubricating performance application technology, specifically to a graphene-based high-performance environmentally friendly lubricating oil and its preparation process. Background Technology

[0002] While traditional lubricants meet the lubrication needs of mechanical equipment to a certain extent, they have significant shortcomings in terms of environmental performance, intelligent response capabilities, and ability to cope with extreme working conditions. Conventional lubricants often rely on petroleum-based raw materials, which are not only limited in resources but may also generate harmful substances during production and use, burdening the environment. Furthermore, traditional lubricants often fail to meet requirements for lubrication performance, anti-wear protection, and stability under high temperature, high pressure, extreme temperature, and heavy load conditions.

[0003] In recent years, with the rise of graphene materials, graphene has been widely regarded as an ideal additive for improving the performance of lubricating oils due to its unique physicochemical properties, such as high thermal conductivity, high mechanical strength, and good interfacial compatibility. However, how to effectively disperse graphene nanosheets and how to functionalize them without compromising their properties have always been challenges facing the industry. Summary of the Invention

[0004] The purpose of this invention is to provide a graphene-based high-performance environmentally friendly lubricating oil and its preparation process, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A graphene-based high-performance environmentally friendly lubricating oil and its preparation process, comprising:

[0007] (a) 0.5-2% by weight of multilayer graphene nanosheets, the surface of which is coated with a metal oxide film of controllable thickness by atomic layer deposition (ALD);

[0008] (b) High-purity PAO synthetic oil with a weight ratio of 97-99.4%;

[0009] (c) 0.1-1% by weight of a multifunctional biodegradable additive containing novel antioxidants and anti-wear agents extracted from marine microorganisms, as well as biopolymer thickeners;

[0010] (d) 0.01-0.5% by weight of nano-sized molybdenum disulfide;

[0011] (e) 0.01-0.1% by weight of nanodiamond powder;

[0012] (f) Antibacterial agent at a weight ratio of 0.001-0.05%.

[0013] Preferably, the graphene nanosheets have an average thickness of less than 3 nm and an average diameter between 1 and 3 μm, and are prepared by plasma-enhanced chemical vapor deposition combined with laser exfoliation technology.

[0014] Preferably, the metal oxide film is titanium dioxide or zinc oxide, and its thickness is in the range of 1-5 nm.

[0015] Preferably, the biopolymer thickener in the multifunctional biodegradable additive is derived from sodium alginate.

[0016] This invention also protects a preparation process for a graphene-based high-performance environmentally friendly lubricating oil, comprising the following steps:

[0017] (a) Under the synergistic effect of ultrasound and microwave, the modified graphene nanosheets are dispersed in a green solvent system to form a highly stable suspension;

[0018] (b) Preheat the high-purity PAO synthetic oil to 105-110°C and introduce inert gas while stirring magnetically;

[0019] (c) With the assistance of ultrasonic cavitation effect, the suspension in step (a) is rapidly injected into the base oil in step (b), and pre-prepared multifunctional biodegradable additives, nano-sized molybdenum disulfide, nano diamond powder and antibacterial agent are added at the same time, and the overall temperature is controlled not to exceed 115°C.

[0020] (d) Supercritical fluid extraction technology, combined with a nanofiltration system, is used to efficiently remove undispersed graphene particles and impurities, while concentrating the target components.

[0021] (e) Under vacuum conditions, the solvent is evaporated using pulse evaporation technology with a gentle temperature and pressure gradient, followed by rapid freeze-drying under inert gas protection to obtain the finished product.

[0022] Preferably, the ultrasonic processing frequency is 40-60kHz, the power density is 0.6-1.0W / cm², the microwave power is 500-800W, and the processing time is controlled at 20-30 minutes.

[0023] Preferably, the supercritical fluid extraction technology uses carbon dioxide as the fluid medium, with the pressure controlled at 70-100 bar, the temperature at 35-45°C, and the duration at no less than 40 minutes.

[0024] Preferably, the pulse evaporation technology uses an intermittent heating method, with the temperature controlled at 55-75℃ and the pressure at 0.01-0.1 mmHg.

[0025] Preferably, the rapid freeze-drying technology is carried out under an absolute pressure of ≤0.01 mmHg, with the temperature dropping to below -40°C for a duration of not less than 2 hours.

[0026] Preferably, the finished product is sealed in an inert gas environment and uses a multi-layer composite material that is moisture-proof, oxygen-proof, and UV-proof.

[0027] The present invention has at least the following beneficial effects:

[0028] (1) In this invention, a metal oxide film, such as TiO2 or ZnO, is coated on the surface of graphene nanosheets by atomic layer deposition (ALD) technology, which enables the graphene nanosheets to intelligently respond to temperature and pressure changes, thereby enhancing the self-repair mechanism and stability of the lubricating oil. Furthermore, by precisely controlling the size and surface modification of the graphene nanosheets, as well as optimizing the selection and ratio of base oil and additives, the lubricating oil of this invention exhibits excellent lubrication performance and anti-wear protection under high temperature, high pressure, extreme temperature and heavy load conditions.

[0029] (2) This solution significantly improves the environmental performance of lubricating oil and reduces its negative impact on the environment by using multifunctional biodegradable additives, including antioxidants and anti-wear agents extracted from marine microorganisms, and biopolymer thickeners derived from sodium alginate.

[0030] (3) This scheme uses advanced preparation technologies, such as ultrasound, microwave, supercritical fluid extraction, pulse evaporation and rapid freeze drying, to ensure the uniform dispersion of graphene nanosheets, the effective fusion of additives and the high quality of the finished product.

[0031] (4) This solution further enhances the anti-wear, friction reduction and antibacterial properties of the lubricating oil by adding nano-sized molybdenum disulfide, nano-diamond powder and antibacterial agent, so that the lubricating oil can adapt to more types of working environments, especially under extreme temperature conditions. Attached Figure Description

[0032] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a process flow diagram of the present invention. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Example 1

[0036] Please see Figure 1 This invention provides a technical solution: a graphene-based high-performance environmentally friendly lubricating oil and its preparation process, comprising:

[0037] (a) 0.5-2% (by weight) of multilayer graphene nanosheets, the surface of which is coated with a metal oxide film of controllable thickness by atomic layer deposition (ALD) to achieve intelligent response to temperature and pressure;

[0038] (b) 97-99.4% (by weight) high-purity PAO synthetic oil with an extremely high viscosity index and extremely low volatility, and specially treated to enhance interfacial compatibility with graphene nanosheets;

[0039] (c) 0.1-1% (by weight) of a multifunctional biodegradable additive containing novel antioxidants and anti-wear agents extracted from marine microorganisms, as well as biopolymer thickeners, to significantly improve environmental performance, lubrication effect and intelligent response capability;

[0040] (d) 0.01-0.5% (by weight) of nano-sized molybdenum disulfide;

[0041] (e) 0.01-0.1% (by weight) of nanodiamond powder;

[0042] (f) 0.001-0.05% (by weight) of antibacterial agent.

[0043] In some embodiments, the graphene nanosheets have an average thickness of less than 3 nm and an average diameter between 1 and 3 μm, and are prepared by plasma-enhanced chemical vapor deposition (PECVD) combined with laser exfoliation. The metal oxide film is titanium dioxide (TiO2) or zinc oxide (ZnO), with a thickness in the range of 1-5 nm. The biopolymer thickener in the multifunctional biodegradable additive is derived from sodium alginate, which not only improves the viscosity adaptability and shear resistance of the lubricating oil, but also maintains good fluidity at low temperatures.

[0044] It should be noted that using plasma-enhanced chemical vapor deposition (PECVD) combined with laser ablation technology to prepare multilayer graphene nanosheets with an average thickness of less than 3 nm and an average diameter between 1 and 3 μm achieves excellent dispersibility, thermal stability, and precisely controlled size distribution. Atomic layer deposition (ALD) is then used to coat the surface of the graphene nanosheets with a metal oxide film of 1-5 nm thickness. The choice of titanium dioxide (TiO2) or zinc oxide (ZnO) promotes the self-healing mechanism of the graphene nanosheets under high temperature and high pressure conditions.

[0045] High-purity PAO synthetic oil was preheated to 105-110℃ and pretreated using a magnetic stirrer under an inert gas atmosphere to enhance its interfacial compatibility with graphene nanosheets. A multifunctional biodegradable additive was formulated containing novel antioxidants and anti-wear agents extracted from marine microorganisms, as well as a biopolymer thickener derived from sodium alginate.

[0046] In some embodiments, the present invention also protects a preparation process for a graphene-based high-performance environmentally friendly lubricating oil, comprising the following steps:

[0047] (a) Modified graphene nanosheets were dispersed in a green solvent system under the synergistic effect of ultrasound and microwave to form a highly stable suspension. The ultrasound treatment frequency was 40-60 kHz, and the power density was 0.6-1.0 W / cm²; the microwave power was 500-800 W, and the treatment time was 20-30 minutes.

[0048] (b) With the assistance of ultrasonic cavitation effect, the suspension in step 4 is rapidly injected into the preheated base oil in step 2, and pre-prepared multifunctional biodegradable additives, nano-sized molybdenum disulfide, nano diamond powder and antibacterial agent are added at the same time, and the overall temperature is controlled not to exceed 115°C.

[0049] (c) Supercritical fluid extraction technology, combined with a nanofiltration system, is used to efficiently remove undispersed graphene particles and impurities while concentrating the target components. Carbon dioxide is used as the fluid medium, with pressure controlled at 70-100 bar, temperature at 35-45°C, and duration not less than 40 minutes.

[0050] (d) Under vacuum conditions, pulse evaporation technology is used, with the temperature controlled at 55-75℃ and the pressure at 0.01-0.1 mmHg, to evaporate the solvent. Subsequently, under an absolute pressure of ≤0.01 mmHg, the temperature is lowered to below -40℃ for at least 2 hours, using rapid freeze-drying technology to maintain the stability of the microstructure and active ingredients of the finished product.

[0051] (e) The finished product is sealed in an inert gas environment and uses a multi-layer composite material that is moisture-proof, oxygen-proof and UV-proof to extend the shelf life and maintain its intelligent response characteristics and environmental performance.

[0052] In summary, through the above steps, a graphene-based high-performance environmentally friendly lubricating oil was successfully prepared. This lubricating oil has excellent lubrication performance, intelligent response capability, and environmental protection characteristics, and is suitable for the lubrication needs of mechanical equipment under various harsh working conditions.

[0053] In some embodiments, the ultrasonic treatment frequency is 40-60kHz, the power density is 0.6-1.0W / cm², the microwave power is 500-800W, and the time is controlled at 20-30 minutes to promote the uniform dispersion of graphene nanosheets and the uniform coating of smart responsive materials, while avoiding structural damage and functional degradation.

[0054] The supercritical fluid extraction operation uses carbon dioxide as the fluid medium, with the pressure controlled at 70-100 bar, the temperature at 35-45°C, and the duration at no less than 40 minutes, in order to achieve efficient separation and purification while maintaining the bioactivity and functionality of the target components.

[0055] The pulsed evaporation technology employs an intermittent heating method, with the temperature controlled at 55-75℃ and the pressure at 0.01-0.1 mmHg, to avoid the decomposition of the base oil and the structural damage to the smart response material, while simultaneously improving evaporation efficiency.

[0056] The rapid freeze-drying technology is carried out under an absolute pressure of ≤0.01 mmHg, with the temperature dropping to below -40°C for a duration of not less than 2 hours, in order to rapidly freeze and sublimate the solvent and maintain the stability of the microstructure and active ingredients of the finished product.

[0057] The finished product is sealed in an inert gas environment and uses a multi-layer composite material that is moisture-proof, oxygen-proof, and UV-proof to extend its shelf life and maintain its intelligent response characteristics and environmental performance.

[0058] Example 2

[0059] In this embodiment, a graphene-based high-performance environmentally friendly lubricating oil (suitable for extreme temperature environments) is prepared.

[0060] This embodiment illustrates a method for preparing a graphene-based high-performance environmentally friendly lubricating oil specifically designed for extreme temperature conditions, as detailed below:

[0061] By employing a hydrothermal method combined with mechanical exfoliation, monolayer graphene nanosheets with a thickness of less than 2 nm and a diameter of 0.5-2 μm were prepared, ensuring that they could maintain a stable structure even at extreme temperatures.

[0062] Electrochemical deposition technology is used to uniformly deposit a metal sulfide film with a thickness of about 2-4 nm on graphene nanosheets, such as molybdenum sulfide (MoS2), to enhance its lubrication performance at low and high temperatures.

[0063] High viscosity index ester synthetic oils are selected, preheated to 110-120℃, and pretreated with high-speed shear equipment under nitrogen protection to improve their bonding force with graphene nanosheets.

[0064] The formulation contains naturally derived fatty acid esters and phospholipids as extreme pressure additives, as well as polyalphaolefin (PAO) thickeners with excellent low-temperature fluidity, to improve the extreme pressure performance of lubricating oils at extreme temperatures.

[0065] Modified graphene nanosheets were uniformly dispersed in a specific low-temperature solvent under the combined action of ultrasound and electromagnetic fields, forming a highly stable suspension. The ultrasound treatment frequency was 30-50 kHz, the power density was 0.4-0.8 W / cm², the electromagnetic field strength was 500-1000 Gauss, and the treatment time was 15-25 minutes.

[0066] With the aid of microwave heating, the suspension is slowly injected into the preheated base oil, while a multifunctional extreme pressure additive is added. The temperature is strictly controlled to not exceed 120°C to ensure the activity of the additive.

[0067] Utilizing advanced ultrafiltration membrane technology combined with an electrodialysis process, it effectively removes undispersed graphene particles and any residual solvents while retaining key components of the lubricating oil. The operating pressure is 20-40 bar, the current density is 0.5-1.0 A / cm², and the treatment time is no less than 30 minutes.

[0068] Under reduced pressure, the solvent is recovered using a rotary evaporator, with the temperature controlled at 40-60℃ and the pressure at 1-10 mmHg. Subsequently, the product is placed in a vacuum drying oven, and the temperature is lowered to below -20℃ for at least 4 hours to ensure thorough drying.

[0069] Finished product packaging

[0070] The finished product is aseptically filled in a nitrogen-filled environment and packaged with a metal composite film with excellent barrier properties to ensure that the lubricating oil maintains its high performance and environmental protection characteristics even at extreme temperatures.

[0071] Example 3

[0072] In this embodiment, a graphene-based high-performance environmentally friendly lubricating oil (for heavy-load applications) is prepared.

[0073] This embodiment describes the preparation process of a graphene-based high-performance environmentally friendly lubricant specifically designed for heavy-duty mechanical equipment:

[0074] Multilayer graphene nanosheets with a thickness of approximately 1.5 nm and a diameter of 2-5 μm were prepared using a microwave-assisted chemical reduction method to meet the high strength requirements of heavy-duty applications.

[0075] By using solution chemistry, an organosilane coupling agent with a thickness of 3-7 nm was modified on the surface of graphene nanosheets to enhance their wear resistance and self-healing ability under high load conditions.

[0076] High molecular weight polyolefin synthetic oil was selected, preheated to 115-125℃, and pretreated under ultrasonic oscillation to improve its interfacial wettability with graphene nanosheets.

[0077] It is formulated with high concentrations of borates and phosphate esters as anti-wear additives, as well as natural thickeners extracted from soybean oil, to enhance the anti-wear protection effect of lubricating oil under heavy load conditions.

[0078] Modified graphene nanosheets were dispersed in a customized solvent system under the combined action of a high-pressure homogenizer and ultrasound to form a highly dispersed and stable suspension. The homogenization pressure was 100-200 bar, the ultrasound frequency was 50-70 kHz, the power density was 0.8-1.2 W / cm², and the processing time was 25-35 minutes.

[0079] Under the combined action of ultrasound and heating and stirring, the suspension is slowly mixed into the preheated base oil, while a multifunctional anti-wear additive is added, and the mixing temperature is controlled to not exceed 130℃.

[0080] High-speed centrifuges combined with nanoscale ceramic filter membranes are used to efficiently remove undispersed graphene particles and any impurities, while concentrating key components. Centrifugation speeds are 10,000-15,000 rpm, filter pore sizes are 10-20 nm, and processing time is no less than 30 minutes. Solvent is recovered using a thin-film evaporator under low-temperature vacuum conditions, with the temperature controlled at 30-50°C and the pressure at 0.1-1 mmHg. Subsequently, the product is placed in a freeze dryer, with the temperature lowered to below -30°C for no less than 6 hours to ensure thorough drying.

[0081] The finished product is packaged in a cleanroom using nitrogen-filled packaging technology and sealed with a multi-layer aluminum-plastic composite material that is moisture-proof and UV-resistant, ensuring its durable performance and environmental advantages in heavy-duty applications.

[0082] In summary, Example 1 focuses on the preparation of a widely applicable high-performance lubricant. By combining PECVD with laser exfoliation technology and ALD-modified graphene nanosheets, using PAO synthetic oil as the base oil, and adding multifunctional biodegradable additives, the product's environmental friendliness and intelligent response characteristics are ensured.

[0083] Example 2: For extreme temperature environments, such as extremely cold or hot conditions, this example uses a hydrothermal method and mechanical exfoliation technology to prepare graphene, combined with electrochemical deposition technology for modification, and uses ester synthetic oils and specific extreme pressure additives to ensure the stability and performance of the lubricating oil under extreme temperatures.

[0084] Example 3: For heavy-duty mechanical equipment, this example uses microwave-assisted chemical reduction to prepare graphene, which is then modified by solution chemistry. Polyolefin synthetic oil is selected and combined with high concentration of anti-wear additives to enhance the wear resistance and self-repair ability of the lubricating oil under high load conditions.

[0085] Comparative Example 1

[0086] A method for preparing a graphene-based nano-lanthanum oxide lubricating oil anti-wear additive is disclosed. The method involves adding graphene oxide to an aqueous solution of lanthanum chloride, ultrasonically dispersing it uniformly, adding ammonia, stirring the mixture, and calcining the resulting precipitate under a nitrogen atmosphere to obtain a graphene-based nano-lanthanum oxide composite. The composite is then added to anhydrous ethanol, ultrasonicated, and the supernatant suspension is added to a base oil for lubricating oil. The mixture is stirred at a certain temperature until the volume of the lubricating oil remains constant to obtain the graphene-based nano-lanthanum oxide lubricating oil anti-wear additive. This invention features a simple and environmentally friendly process. The prepared additive significantly improves the anti-wear performance of lubricating oil, provides good protection for friction pairs, and effectively extends the service life of mechanical components.

[0087] Comparative Example 2

[0088] A graphene compound for use as a lubricating oil additive, its preparation method, and its application are disclosed. This invention provides an oil-soluble graphene compound with the structural formula: Γ~N~R, where Γ is graphene oxide, N is an aliphatic or aromatic bridging compound with all terminal groups being -NH2 or -OH, or an aliphatic or aromatic bridging compound with one end being -NH2 and the other end being -OH, and R is a compound containing a polyisobutylene succinic anhydride structure. This graphene compound exhibits excellent oil solubility, can be well dispersed in lubricating oil, and possesses excellent anti-wear and extreme pressure properties; it also does not contain environmentally harmful elements such as sulfur, phosphorus, and chlorine, making it green and environmentally friendly; moreover, the preparation process is simple, the reaction conditions are mild, and there are no special requirements for chemical equipment; it can be applied in the fields of lubricating oils and greases.

[0089] In summary, the embodiments, by introducing material preparation technology, optimized process flow, and environmentally friendly additives, not only improved the performance and applicability of lubricating oil, but also enhanced the environmental attributes of the product, demonstrating the comprehensive advantages brought about by technological progress.

[0090] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0091] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A preparation process for a graphene-based high-performance environmentally friendly lubricating oil, characterized in that, The high-performance environmentally friendly lubricant contains: Multilayer graphene nanosheets with a weight ratio of 0.5-2% are coated with a metal oxide film of controllable thickness using atomic layer deposition (ALD) technology. High-purity PAO synthetic oil with a weight ratio of 97-99.4%; A multifunctional biodegradable additive at a weight ratio of 0.1-1%, containing antioxidants and anti-wear agents extracted from marine microorganisms, as well as biopolymer thickeners; Nanoscale molybdenum disulfide, 0.01-0.5% by weight; Nanodiamond powder at a weight ratio of 0.01-0.1%; Antibacterial agent at a weight ratio of 0.001-0.05%; The preparation process of the high-performance environmentally friendly lubricating oil includes the following steps: (a) Under the synergistic effect of ultrasound and microwave, the modified graphene nanosheets are dispersed in a green solvent system to form a highly stable suspension; (b) Preheat the high-purity PAO synthetic oil to 105-110°C and introduce inert gas while stirring magnetically; (c) With the assistance of ultrasonic cavitation effect, the suspension in step (a) is rapidly injected into the base oil in step (b), and pre-prepared multifunctional biodegradable additives, nano-sized molybdenum disulfide, nano diamond powder and antibacterial agent are added at the same time, and the overall temperature is controlled not to exceed 115°C. (d) Supercritical fluid extraction technology, combined with a nanofiltration system, is used to efficiently remove undispersed graphene particles and impurities, while concentrating the target components. (e) Under vacuum conditions, the solvent is evaporated using pulse evaporation technology and intermittent heating, with the temperature controlled at 55-75°C and the pressure at 0.01-0.1 mmHg. Then, the finished product is obtained by rapid freeze-drying under inert gas protection.

2. The preparation process of a graphene-based high-performance environmentally friendly lubricating oil according to claim 1, characterized in that: The graphene nanosheets have an average thickness of less than 3 nm and an average diameter between 1 and 3 μm, and are prepared by plasma-enhanced chemical vapor deposition combined with laser exfoliation technology.

3. The preparation process of a graphene-based high-performance environmentally friendly lubricating oil according to claim 1, characterized in that: The metal oxide film is titanium dioxide or zinc oxide, and its thickness is in the range of 1-5 nm.

4. The preparation process of a graphene-based high-performance environmentally friendly lubricating oil according to claim 1, characterized in that: The biopolymer thickener in the multifunctional biodegradable additive is derived from sodium alginate.

5. The preparation process of a graphene-based high-performance environmentally friendly lubricating oil according to claim 1, characterized in that: The ultrasonic waves are processed at a frequency of 40-60 kHz and a power density of 0.6-1.0 W / cm². 2 The microwave power is 500-800W, and the time is controlled at 20-30 minutes.

6. The preparation process of a graphene-based high-performance environmentally friendly lubricating oil according to claim 1, characterized in that: In the supercritical fluid extraction technology, carbon dioxide is used as the fluid medium, the pressure is controlled at 70-100 bar, the temperature is 35-45℃, and the duration is not less than 40 minutes.

7. The preparation process of a graphene-based high-performance environmentally friendly lubricating oil according to claim 1, characterized in that: The rapid freeze-drying technology is carried out under an absolute pressure of ≤0.01 mmHg, with the temperature dropping to below -40°C for a duration of not less than 2 hours.

8. The preparation process of a graphene-based high-performance environmentally friendly lubricating oil according to claim 1, characterized in that: The finished product is sealed in an inert gas environment and uses a multi-layer composite material that is moisture-proof, oxygen-proof, and UV-proof.

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