Multifunctional fluorosilicone biolipid nano oil displacement agent and preparation method thereof

Abstract

The invention discloses a multifunctional fluorosilicone biolipid nano oil-displacing agent, which comprises 20-40% of fluorosilicone surface active nano fluid, 10-20% of a surfactant, 10-20% of a surfactant, and the balance of water. 5%-10% of biolipid; and the balance of water. Wherein the fluorosilicone surface active nanofluid is prepared by grafting and modifying a modified fluorocarbon glycerophosphate intermediate and nanosilicon dioxide. The oil-displacing agent disclosed by the invention has a nano-scale'seepage-displacing-washing 'integrated multifunctional effect, is excellent in temperature resistance, salt tolerance, oil washing efficiency and imbibition oil-displacing capacity, is suitable for low-permeability oil reservoirs with the temperature of 140 DEG C and the degree of mineralization of 150000mg / L, has the comprehensive capacity improved by more than 30% compared with that of an imbibition oil-displacing agent used on site, and has a good application prospect. The multifunctional fluorosilicone biolipid nano oil displacement agent has wide application prospects in hydrofracture of low-permeability reservoirs and later yield increasing and stabilizing processes.

Description

Technical Field

[0001] This invention relates to an oil displacement agent, and more specifically, to a multifunctional fluorosilicone bio-lipid nano-oil displacement agent. Background Technology

[0002] As conventional oil and gas resource development approaches its limits, low-permeability reservoirs (permeability ≤ 50 mD) have become a key area for global oil and gas development. However, these reservoirs face core challenges such as complex pore structures, low displacement efficiency, and high injection pressure. Traditional chemical flooding agents (such as polymers and surfactants) are prone to blockage in low-permeability formations and cannot achieve effective wetting reversal due to their large molecular size and limited interfacial regulation capabilities.

[0003] Currently, traditional chemical flooding systems mainly include polymer flooding and surfactant flooding. The oil displacement mechanism of polymer flooding (such as polyacrylamide) is mainly to increase the sweep efficiency by increasing the viscosity of the displaced phase, but it is prone to failure due to shear degradation and pore blockage in low-permeability formations. The oil displacement mechanism of surfactant flooding is mainly to achieve oil washing by reducing the oil-water interfacial tension, but it has problems such as serious adsorption loss and poor temperature and salt resistance.

[0004] Single nanoparticle oil displacement agents (such as SiO2 and Al2O3 nanoparticles) mainly improve oil displacement efficiency by reducing interfacial tension and regulating wettability. However, their tendency to aggregate and simple mechanism of action lead to low oil displacement efficiency. Amphiphilic nanocomposite materials (such as Janus-type nanoparticles) mainly achieve dual affinity between oil and water through asymmetric structure, but their complex preparation process and high cost limit their large-scale application.

[0005] Currently, nano-displacement agents on the market have improved oil recovery by 8%–15% in laboratory core displacement experiments, but the improvement in field tests is insufficient and significantly different from that in laboratory experiments. The main problems include: traditional nanoparticles struggle to balance small size and strong interfacial activity, leading to a contradiction between size effects and reservoir compatibility; existing technologies focus on single mechanisms, lacking an integrated nanoscale "displacement-permeation-washing" system, and failing to achieve synergistic effects across multiple mechanisms; nanoparticles are easily deactivated during reservoir migration due to pH and ionic strength, resulting in insufficient long-term stability. Addressing the challenges of increasing and stabilizing production in low-permeability reservoirs and the reliance on single-technology approaches, conventional displacement agents exhibit poor temperature and salt resistance, necessitating the development of a targeted nano-composite permeation displacement agent. Summary of the Invention

[0006] Therefore, it is necessary to provide a multifunctional fluorosilicone bio-lipid nano-oil displacement agent to address the aforementioned technical problems.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] A multifunctional fluorosilicone bio-lipid nano-oil displacement agent, comprising, by weight parts:

[0009] Fluorosilicone surface-active nanofluids, 20%–40%;

[0010] Biological lipids, 5%–10%;

[0011] The remainder is water;

[0012] The fluorosilicone surface-active nanofluid is prepared by grafting a modified fluorocarbon glycerol phosphate intermediate with nano-silica.

[0013] In a preferred embodiment, the bio-lipid is at least one of rhamnolipid and sophorolipid.

[0014] A method for preparing a multifunctional fluorosilicone bio-lipid nano-oil displacement agent includes the following steps:

[0015] Step S1: Add 1 mol of hexafluoropropylene oxide and a certain amount of organic solvent dimethylformamide to a three-necked flask, purge with nitrogen three times to remove oxygen, stir magnetically to swell for 1 hour to form a homogeneous solution, slowly add potassium fluoride, stir at room temperature for 1 hour, add 2-3 mol of ammonia water to the three-necked flask, stir continuously, maintain a nitrogen atmosphere during the process, and adjust the pH value to 9-11 with sodium hydroxide solution.

[0016] Step S2: Slowly add a certain amount of dichlorodimethylsilane to step S1, stir for 0.5 hours, add triethylamine and tetrahydrofuran, continue stirring, maintain a nitrogen atmosphere, and adjust the pH value to 9-11 with sodium hydroxide solution.

[0017] Step S3: Add a certain amount of catalyst to step S2, stir continuously, gradually heat to 120°C, slowly add a certain amount of polyglycerol phosphate, react for 2-3 hours, and obtain the modified fluorocarbon glycerol phosphate intermediate.

[0018] Step S4: Add 10g of nano-silica particles to 100mL of ethanol, stir for 10 minutes, add 3g of 3-aminopropyltrimethoxysilane, react at 70-90℃ for 2-4 hours, wash with deionized water 2-3 times, and dry to obtain aminated nano-silica particles.

[0019] Step S5: Add 1 mol of the modified fluorocarbon glycerol phosphate intermediate obtained in step S3 to 100 mL of LDMF, stir and heat to 60-80 °C, then slowly add 1 mol of chloroacetic acid and stir to react for 1-2 hours.

[0020] Step S6: Add 5g of aminated nano-silica particles to step S5, maintain the temperature at 60-80℃, and react for 4-6 hours to obtain fluorosilicone surface-active nanofluid.

[0021] Step S7: Heat deionized water to 40-50℃, add the fluorosilicone surface-active nanofluid obtained in step S6, and stir with a homogenizer at 4000r / min for 0.5 hours.

[0022] Step S8: Add the bio-lipids in step S7, stir with a homogenizer at 4000 r / min for 0.5 hours, and then cool down.

[0023] In a preferred embodiment, the bio-lipid is at least one of rhamnolipid and sophorolipid.

[0024] In a preferred embodiment, the magnetic stirring speed in step S1 is 300 rpm.

[0025] In a preferred embodiment, in step S3, the degree of polymerization n of the polyglycerol phosphate is 1-5, and the degree of polymerization m of the modified fluorocarbon glycerol phosphate intermediate is 10-15.

[0026] In a preferred embodiment, the catalyst in step S3 is stannous octoate.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The oil displacement agent of this invention has a nanoscale integrated multi-functional "permeation-displacement-washing" function. It has excellent temperature and salt resistance, oil washing efficiency and permeation displacement ability. It is suitable for low-permeability reservoirs with a salinity of 150,000 mg / L and a salinity of 140℃. Its comprehensive ability is more than 30% higher than that of permeation displacement agents used in the field. This multi-functional fluorosilicone bio-lipid nano-displacement agent has broad application prospects in hydraulic fracturing and subsequent production enhancement and stabilization processes in low-permeability reservoirs. Attached Figure Description

[0029] To more clearly illustrate the solutions in this invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a process flow diagram for preparing the modified fluorocarbon glycerol phosphate intermediate of the present invention;

[0031] Figure 2 This is a flow chart of the preparation process of the fluorosilicone surface-active nanofluid of the present invention. Detailed Implementation

[0032] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0033] This multifunctional fluorosilicone bio-lipid nano-oil displacement agent, by weight, comprises:

[0034] Fluorosilicone surface-active nanofluids, 20%–40%;

[0035] Biological lipids, 5%–10%;

[0036] The remainder is water;

[0037] The fluorosilicone surface-active nanofluid is prepared by grafting a modified fluorocarbon glycerol phosphate intermediate with nano-silica.

[0038] It should be noted that the bio-lipid is at least one of rhamnolipid or sophorolipid.

[0039] The preparation method of this multifunctional fluorosilicone bio-lipid nano-oil displacement agent includes the following steps:

[0040] Step S1, as follows Figure 1 As shown, 1 mol of hexafluoropropylene oxide and a certain amount of organic solvent dimethylformamide (DMF) were added to a three-necked flask. The mixture was purged with nitrogen three times to remove oxygen. The mixture was then magnetically stirred and swollen for 1 hour to form a homogeneous solution. Potassium fluoride was slowly added and the mixture was stirred at room temperature for 1 hour. 2-3 mol of ammonia water was added to the three-necked flask and stirred continuously while maintaining a nitrogen atmosphere. The pH value was adjusted to 9-11 with sodium hydroxide solution.

[0041] Step S2: Slowly add a certain amount of dichlorodimethylsilane to step S1, stir for 0.5 hours, add triethylamine (TEA) and tetrahydrofuran (THF), continue stirring, maintain a nitrogen atmosphere during the process, and adjust the pH value to 9-11 with sodium hydroxide solution.

[0042] Step S3: Add a certain amount of catalyst to step S2, stir continuously, gradually heat to 120°C, slowly add a certain amount of polyglycerol phosphate, react for 2-3 hours, and obtain the modified fluorocarbon glycerol phosphate intermediate.

[0043] Step S4, as follows Figure 2 As shown, 10g of nano-silica particles were added to 100mL of ethanol and stirred for 10 minutes. Then, 3g of 3-aminopropyltrimethoxysilane was added and reacted at 70-90℃ for 2-4 hours. The mixture was washed 2-3 times with deionized water and dried to obtain aminated nano-silica particles.

[0044] Step S5: Add 1 mol of the modified fluorocarbon glycerol phosphate intermediate obtained in step S3 to 100 mL of LDMF, stir and heat to 60-80 °C, then slowly add 1 mol of chloroacetic acid and stir to react for 1-2 hours.

[0045] Step S6: Add 5g of aminated nano-silica particles to step S5, maintain the temperature at 60-80℃, and react for 4-6 hours to obtain fluorosilicone surface-active nanofluid.

[0046] Step S7: Heat deionized water to 40-50℃, add the fluorosilicone surface-active nanofluid obtained in step S6, and stir with a homogenizer at 4000r / min for 0.5 hours.

[0047] Step S8: Add the bio-lipids in step S7, stir with a homogenizer at 4000 r / min for 0.5 hours, and then cool down.

[0048] It should be noted that in step S1, the magnetic stirring speed is 300 rpm.

[0049] In step S3, the degree of polymerization n of the polyglycerol phosphate ester is 1-5, and the degree of polymerization m of the modified fluorocarbon glycerol phosphate ester intermediate is 10-15, which is achieved by controlling the molar ratio of each raw material. Additionally, the catalyst is stannous octoate Sn(Oct)2.

[0050] The preparation method of this multifunctional fluorosilicone bio-lipid nano-oil displacement agent will be further explained below.

[0051] Example 1: The multifunctional fluorosilicone bio-lipid nano-oil displacement agent of this example is physically compounded according to the above preparation steps by controlling variables. Its raw material composition and the mass percentage of each component are: 20% fluorosilicone surface-active nanofluid, 5% rhamnolipid, and the balance is deionized water.

[0052] Example 2:

[0053] The multifunctional fluorosilicone bio-lipid nano-oil displacement agent of this embodiment differs from that of Embodiment 1 in that it contains 30% fluorosilicone surface-active nanofluid, 5% rhamnolipid, and the remainder is deionized water.

[0054] Example 3:

[0055] The multifunctional fluorosilicone bio-lipid nano-oil displacement agent of this embodiment differs from that of Embodiment 1 in that it contains 40% fluorosilicone surface-active nanofluid, 5% rhamnolipid, and the remainder is deionized water.

[0056] Example 4:

[0057] The multifunctional fluorosilicone bio-lipid nano-oil displacement agent of this embodiment differs from that of Embodiment 1 in that it contains 30% fluorosilicone surface-active nanofluid, 10% rhamnolipid, and the remainder is deionized water.

[0058] Example 5:

[0059] The multifunctional fluorosilicone bio-lipid nano-oil displacement agent of this embodiment differs from that of Embodiment 1 in that it contains 30% fluorosilicone surface-active nanofluid, 5% sophorolipid, and the remainder is deionized water.

[0060] Example 6:

[0061] The multifunctional fluorosilicone bio-lipid nano-oil displacement agent of this embodiment differs from that of Embodiment 1 in that it contains 30% fluorosilicone surface-active nanofluid, 10% sophorolipid, and the remainder is deionized water.

[0062] The following tests were conducted on the oil-water interfacial tension, oil washing efficiency, and static permeation efficiency of the multifunctional fluorosilicone bio-lipid nano-oil displacement agent provided in the above embodiments under different temperature and salinity conditions. The performance of the agent was also compared with that of two permeation oil displacement agents used in the field under the same test conditions.

[0063] The instrument used in the test was a TX-500D full-range rotating drop interfacial tensiometer; the test water was prepared by: 1. NaCl, CaCl2, MgCl2, KCl, Na2SO4, and NaHCO3 after analysis of the water extracted from the Subei Basin, with a mineralization of 50,000–150,000 mg / L; 2. Calcium and magnesium ion mineralized water was prepared by mixing CaCl2 and MgCl2 in the proportions of the water extracted from the Subei Basin, with a concentration of 500–2000 mg / L.

[0064] The specific testing method is as follows:

[0065] 1. Oil-water interfacial tension test:

[0066] The six examples and two field-use percolation displacement agents were prepared into aqueous solutions at effective concentrations of 0.1% and 0.3%, respectively. The experiments were conducted according to the steps in section 6.6 of Q / SH CG0079—2021 "Technical Requirements for Surfactants for Oil Displacement" regarding interfacial tension. The experimental results are shown in Table 1.

[0067] Table 1 Comparison of oil-water interfacial tension among different permeation displacement agents

[0068]

[0069] As can be seen from the data in Table 1, the oil-water interfacial tension in all six embodiments is lower than that of the two oil displacement agents used in the field. In particular, in Cases 3 and 6, at a concentration of 0.3%, the interfacial tension is as low as 1.3 × 10⁻³ mN / m and 1.6 × 10⁻³ mN / m, respectively, significantly better than field oil displacement agent 1 (4.2 × 10⁻³ mN / m) and field oil displacement agent 2 (4.9 × 10⁻³ mN / m). This indicates that the multifunctional fluorosilicone bio-lipid nano-oil displacement agent of the present invention has a lower oil-water interfacial tension, which can more effectively reduce the oil-water interfacial tension, thereby improving oil fluidity and enhancing the oil displacement effect.

[0070] 2. Washing efficiency test:

[0071] The six examples and two field-use percolation displacement agents were prepared into aqueous solutions at an effective content concentration of 0.3%. The experiments were conducted according to the steps in step 6.9 of Q / SH CG0079—2021 "Technical Requirements for Surfactants for Oil Displacement". The quartz sand used for oil sand preparation was 250-300 mesh (simulating formation permeability ≤50mD). The experimental results are shown in Table 2.

[0072] Table 2: Comparison of washing efficiency of different permeation displacement agents

[0073] Oil displacement agent name Oil washing efficiency / % On-site oil displacement agent 1 47.87 On-site oil displacement agent 2 45.62 Case 1 52.76 Case 2 58.54 Case 3 65.23 Case 4 58.97 Case 5 55.77 Case Six 62.54

[0074] Table 2 shows that the oil washing efficiency of all six embodiments is higher than that of the two oil displacement agents used in the field. Among them, Case 3 has the highest oil washing efficiency, reaching 65.23%, while the oil washing efficiencies of field displacement agent 1 and field displacement agent 2 are 47.87% and 45.62%, respectively. This indicates that the oil displacement agent of the present invention has a significant advantage in oil washing efficiency, and can more effectively wash crude oil from oil sands, thereby improving the oil recovery rate of the reservoir.

[0075] 3. Static absorption capacity test:

[0076] Six examples and two field-use percolation displacement agents were prepared into aqueous solutions at an effective concentration of 0.3%. Quartz sand (250-300 mesh) was filled into glass test tubes with a length of 150 mm and an inner diameter of 20 mm, to a filling height of 4 / 5-5 / 6 of the test tube length. The percolation displacement agent aqueous solution was slowly added dropwise until the quartz sand was submerged. Oil sand was prepared according to the steps in 6.9.1 of Q / SH CG0079—2021 "Technical Requirements for Surfactants for Oil Displacement," where the quartz sand used for oil sand preparation had a mesh size of 250-300 (simulating formation permeability ≤50 mD). Oil sand was again layered into the glass test tube until the mouth of the test tube was reached, compacted, and then the displacement agent aqueous solution was slowly added dropwise until the liquid overflowed. The test tube was then sealed to obtain a simulated core. The simulated core was inverted and placed in the target reservoir for temperature enhancement. The final height h of crude oil intrusion into the quartz sand was recorded. The experimental results are shown in Table 3.

[0077] Table 3: Comparison of Static Penetration Height of Different Penetration Displacement Agents

[0078] Oil displacement agent name Immersion height / mm On-site oil displacement agent 1 32 On-site oil displacement agent 2 27 Case 1 39 Case 2 53 Case 3 68 Case 4 57 Case 5 47 Case Six 62

[0079] As can be seen from the data in Table 3, the percolation heights of all six embodiments are higher than those of the two oil displacement agents used in the field. Among them, Case 3 has the highest percolation height, reaching 68 mm, while the percolation heights of field oil displacement agent 1 and field oil displacement agent 2 are 32 mm and 27 mm, respectively. This indicates that the oil displacement agent of the present invention has a stronger percolation capacity, which can more effectively extract crude oil from the formation and improve the recovery efficiency of the reservoir.

[0080] 4. Temperature and salt resistance tests:

[0081] Temperature resistance test: The six examples and two field-use permeation displacement agents were prepared into aqueous solutions at an effective content of 0.3%. After aging at different temperatures for 24 hours, the oil washing efficiency test was conducted. The experimental results are shown in Table 4-1.

[0082] Salt resistance test: The six examples and two field-use percolation displacement agents were prepared into aqueous solutions with an effective content of 0.3% using simulated mineralized water with different mineralization or different calcium and magnesium ion concentrations. The experiment was conducted according to the oil washing efficiency test method. The experimental results are shown in Tables 4-2 and 4-3.

[0083] Table 4-1 Comparison of oil washing efficiency of permeation displacement agents after aging at different temperatures

[0084]

[0085]

[0086] As can be seen from the data in Table 4-1, the oil washing efficiency of the two field-used oil displacement agents decreases significantly with increasing temperature. However, the six embodiments of this invention maintain relatively high oil washing efficiency at different temperatures. At 140℃, the oil washing efficiencies of field-used oil displacement agent 1 and field-used oil displacement agent 2 decrease to 29.32% and 24.27%, respectively, while the oil washing efficiency of Case 3 still reaches 58.13%. This indicates that the oil displacement agent of this invention has good temperature resistance and can maintain high oil washing efficiency under high-temperature conditions, making it suitable for the exploitation of high-temperature oil reservoirs.

[0087] Table 4-2: Comparison of oil washing efficiency of permeation displacement agents under different salinities

[0088]

[0089] As can be seen from the data in Table 4-2, the oil washing efficiency of the two field-used oil displacement agents decreased significantly with increasing salinity, while the six embodiments of the present invention maintained high oil washing efficiency under different salinity conditions. For example, at a salinity of 150,000 mg / L, the oil washing efficiency of field-used oil displacement agent 1 and field-used oil displacement agent 2 decreased to 37.24% and 34.88%, respectively, while the oil washing efficiency of Case 3 still reached 59.66%. This indicates that the oil displacement agent of the present invention has good salt resistance and can maintain high oil washing efficiency under high salinity conditions, making it suitable for the exploitation of high-salinity oil reservoirs.

[0090] Table 4-3: Comparison of oil washing efficiency of water-permeable oil displacement agents with different calcium and magnesium ion concentrations

[0091]

[0092] As can be seen from the data in Table 4-3, the two field-used oil displacement agents exhibited a significant decrease in oil washing efficiency and even precipitation at high calcium and magnesium ion concentrations. In contrast, the six embodiments of this invention maintained high oil washing efficiency under different calcium and magnesium ion concentrations. For example, at a calcium and magnesium ion concentration of 2000 mg / L, field-used oil displacement agents 1 and 2 showed significant precipitation, while the oil washing efficiency of Case 3 still reached 54.84%. This indicates that the oil displacement agent of this invention has excellent resistance to calcium and magnesium ions, maintaining high oil washing efficiency under high calcium and magnesium ion concentrations, and is suitable for oil reservoir development under complex water quality conditions.

[0093] In summary, the multifunctional fluorosilicone bio-lipid nano-displacement agent of the present invention is superior to the oil displacement agents used in the field in terms of oil-water interfacial tension, oil washing efficiency, static permeation capacity, temperature resistance, salt resistance and calcium and magnesium ion resistance. It has significant performance advantages, can effectively improve the recovery rate of low-permeability reservoirs, and has broad application prospects.

[0094] This invention first uses raw materials such as hexafluoropropylene oxide, dichlorodimethylsilane, polyglycerol phosphate and nano silica particles to prepare fluorosilicone surface-active nanofluids through a chemical synthesis process, and then combines them with bio-lipids and water in a certain proportion to prepare a multifunctional fluorosilicone bio-lipid nano-oil displacement agent.

[0095] Because the polyglycerol phosphate moiety can significantly reduce the oil-water interfacial tension, thereby improving oil fluidity; the perfluoropolyether chain can increase the solubility of molecules in the oil phase, which helps to improve the oil phase penetration ability of the displacement agent; the aminosilane moiety can enhance the adsorption of molecules to the rock surface, which helps to increase the residence time of the displacement agent in the reservoir; nanoparticles can penetrate into the tiny pores that traditional displacement agents cannot reach, forming stable migration channels and effectively reducing the oil-water interfacial tension; and bio-lipids have good emulsifying and biodegradable capabilities. Through the synergistic effect of strong penetration, low interfacial tension, and strong emulsifying ability, the efficiency of percolation displacement is significantly improved.

[0096] This oil displacement system achieves synergistic effects through strong permeability, low interfacial tension, and strong emulsification, exhibiting a nanoscale integrated multifunctional "permeation-displacement-washing" function. It boasts excellent temperature and salt resistance, oil washing efficiency, and permeation displacement capacity, making it suitable for low-permeability reservoirs with a salinity of 150,000 mg / L and a comprehensive performance that is more than 30% higher than that of permeation displacement agents used in the field. This multifunctional fluorosilicone bio-lipid nano-displacement agent has broad application prospects in hydraulic fracturing and subsequent production enhancement and stabilization processes in low-permeability reservoirs.

[0097] Obviously, the embodiments described above are only some embodiments of this application, and not all embodiments. The accompanying drawings show preferred embodiments of this application, but do not limit the patent scope of this application.

Claims

1. A multifunctional fluorosilicone bio-lipid nano-oil displacement agent, comprising, by weight parts: Fluorosilicone surface-active nanofluids, 20%–40%; Biological lipids, 5%–10%; The remainder is water; in, The fluorosilicone surface-active nanofluid is prepared by grafting a modified fluorocarbon glycerol phosphate intermediate with nano-silica.

2. The multifunctional fluorosilicone bio-lipid nano-oil displacement agent according to claim 1, characterized in that, The bio-lipid is at least one of rhamnolipid and sophorolipid.

3. A method for preparing the multifunctional fluorosilicone bio-lipid nano-oil displacement agent as described in claim 1, comprising the steps of: Step S1: Add 1 mol of hexafluoropropylene oxide and a certain amount of organic solvent dimethylformamide to a three-necked flask, purge with nitrogen three times to remove oxygen, stir magnetically to swell for 1 hour to form a homogeneous solution, slowly add potassium fluoride, stir at room temperature for 1 hour, add 2-3 mol of ammonia water to the three-necked flask, stir continuously, maintain a nitrogen atmosphere during the process, and adjust the pH value to 9-11 with sodium hydroxide solution. Step S2: Slowly add a certain amount of dichlorodimethylsilane to step S1, stir for 0.5 hours, add triethylamine and tetrahydrofuran, continue stirring, maintain a nitrogen atmosphere, and adjust the pH value to 9-11 with sodium hydroxide solution. Step S3: Add a certain amount of catalyst to step S2, stir continuously, gradually heat to 120°C, slowly add a certain amount of polyglycerol phosphate, react for 2-3 hours, and obtain the modified fluorocarbon glycerol phosphate intermediate. Step S4: Add 10g of nano-silica particles to 100mL of ethanol, stir for 10 minutes, add 3g of 3-aminopropyltrimethoxysilane, react at 70-90℃ for 2-4 hours, wash with deionized water 2-3 times, and dry to obtain aminated nano-silica particles. Step S5: Add 1 mol of the modified fluorocarbon glycerol phosphate intermediate obtained in step S3 to 100 mL of LDMF, stir and heat to 60-80 °C, then slowly add 1 mol of chloroacetic acid and stir to react for 1-2 hours. Step S6: Add 5g of aminated nano-silica particles to step S5, maintain the temperature at 60-80℃, and react for 4-6 hours to obtain fluorosilicone surface-active nanofluid. Step S7: Heat deionized water to 40-50℃, add the fluorosilicone surface-active nanofluid obtained in step S6, and stir with a homogenizer at 4000r / min for 0.5 hours. Step S8: Add the bio-lipids in step S7, stir with a homogenizer at 4000 r / min for 0.5 hours, and then cool down.

4. The preparation method of the multifunctional fluorosilicone bio-lipid nano-oil displacement agent according to claim 3, characterized in that, The bio-lipid is at least one of rhamnolipid and sophorolipid.

5. The preparation method of the multifunctional fluorosilicone bio-lipid nano-oil displacement agent according to claim 3, characterized in that, In step S1, the magnetic stirring speed is 300 rpm.

6. The multifunctional fluorosilicone bio-lipid nano-oil displacement agent according to claim 3, characterized in that, In step S3, the degree of polymerization n of the polyglycerol phosphate is 1-5, and the degree of polymerization m of the modified fluorocarbon glycerol phosphate intermediate is 10-15.

7. The multifunctional fluorosilicone bio-lipid nano-oil displacement agent according to claim 3, characterized in that, In step S3, the catalyst is stannous octoate.

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