A biomimetic micro-nano rough surface porous material for deep removal of low-concentration emulsified oil and a preparation method thereof

Abstract

The application discloses a kind of biomimetic micro-nano rough surface porous material for low concentration emulsified oil deep removal and preparation method.The porous material is formed by eutectic solvent and high-pressure nitrogen gas, and the rough interface is constructed by uniformly embedding organic modified zirconium hydrogen phosphate dihydrate nanoparticles in the skeleton, with specific surface area >900m 2 / g, average pore size <8nm three-dimensional network structure and super oil-wetting hydrophobic performance, the material uses eutectic solvent and nitrogen gas green pore-forming, no organic solvent residue;After in-situ uniform embedding of nano zirconium hydrogen phosphate dihydrate in resin skeleton by organic modification, rough interface, electrostatic adsorption synergistic mechanism is constructed, which gives the porous material rich surface charge and in-situ electrostatic demulsification and separation effect, with separation efficiency of oil-water emulsion higher than 94% after regeneration and repeated use for more than 5 times.The material has strong hydrophobicity and high adsorption capacity, realizing continuous and efficient purification of oily wastewater, with oil content in effluent ≤10ppm.

Description

Technical Field

[0001] This invention relates to the field of oil-water separation materials, and in particular to a biomimetic micro-nano rough surface porous adsorption resin based on a dynamic pressure-controlled pore-forming mechanism and its preparation method, which is particularly suitable for the deep purification treatment of wastewater containing low concentrations of emulsified oil (≤200 ppm). Background Technology

[0002] Oil in oily wastewater generally exists in five forms: suspended oil, dispersed oil, emulsified oil, dissolved oil, and oil solids. Treatment technologies for oily wastewater include biological methods, chemical methods, membrane filtration, coalescence, and adsorption. These methods can effectively separate most of the suspended, dispersed, and oil solids from the water, but a significant amount of emulsified and dissolved oil remains. The difficulty in treating emulsified oil lies primarily in its stable emulsified film, which hinders oil droplet coalescence. Dissolved oil droplets are much smaller than emulsified oil droplets, making them even more difficult to remove once they enter the environment. While membrane separation offers high retention efficiency for oily wastewater, it is prone to fouling, suffers from high pressure loss, and incurs high maintenance costs. Adsorption methods offer the advantage of oil resource recovery compared to other methods for the deep treatment of low-concentration oily wastewater. Polymer-based adsorption resins have attracted widespread attention due to their high mechanical strength, large specific surface area, and ease of functional modification. The typical preparation method is suspension polymerization, which uses divinylbenzene as a crosslinking monomer and carries out free radical polymerization under the protection of a dispersant, and introduces a porogen to construct a porous structure. However, the existing technology still has the following key problems: (1) serious porogen residue: In the conventional macroporous resin preparation process, organic solvents such as toluene, cyclohexanol, and n-heptane are commonly used as porogens. For example, Chinese invention patent with publication number CN116333203A discloses a method for preparing macroporous adsorption resin using toluene, xylene, and liquid paraffin as porogens. Although a certain porosity can be obtained, these solvents have problems such as high volatility, high toxicity, and poor biodegradability. Moreover, they are difficult to completely remove after polymerization, which can easily cause secondary pollution and seriously affect the safety of effluent water quality. In recent years, low eutectic solvents (DES) have attracted attention due to their green and low-cost characteristics, but in practical applications, they still face problems such as wide pore size distribution and high closed-pore rate. (2) The adsorption mechanism is simple and lacks selective response to complex emulsion systems: At present, most oil-water separation resins rely solely on hydrophobic interactions to enrich oil molecules, which is a passive adsorption mechanism. They lack the ability to selectively recognize different types of emulsions (such as anionic, cationic, and nonionic emulsions). In particular, when treating emulsified oily wastewater containing quaternary ammonium salt cationic surfactants, traditional resins often have low adsorption efficiency. For example, Zhou Yanbo, Ye Junmiao, Wang Zhanxin, et al. Study on the treatment of emulsified oil wastewater with quaternary ammonium salt modified resin [J]. China Water & Wastewater, 2008, 24(3):60-63. A novel quaternary ammonium salt modified resin capable of demulsifying emulsified oil wastewater was prepared by grafting long-branched alkyl quaternary ammonium salts onto polystyrene cation exchange resin via ion exchange. The modified resin can separate emulsified oil by demulsifying the emulsified oil itself without the need to add additional surfactants to the wastewater. However, the removal effect is better only under alkaline conditions of influent, with a removal rate of 82.1% for emulsified oil.Chinese invention patent CN101967212A discloses an acrylate polymer high oil-absorbing resin and its preparation method and uses. It uses acrylate and styrene as the main monomers and prepares a high oil-absorbing gel resin through free radical polymerization. However, it still fails to break through the limitation of single hydrophobic adsorption and fails to construct a dual-mode synergistic adsorption mechanism of "hydrophobic enrichment + electrostatic attraction". (3) Poor regeneration performance, which makes it difficult to meet the requirements of continuous operation: Most commercial adsorption resins have problems such as structural collapse, cross-linking network breakage and particle pulverization after repeated solvent elution, resulting in continuous decay of adsorption capacity. This is mainly due to the lack of rigid support in the resin matrix during repeated swelling-shrinkage. Introducing an appropriate amount of rigid inorganic filler is expected to enhance the stability of the skeleton, inhibit deformation and extend service life. However, the existing technology does not organically combine the structural enhancement effect of functional filler with green process and high-performance adsorption, and lacks systematic design.

[0003] Although various adsorption resins have been used for oil-water separation, there are still significant shortcomings in the preparation of separation resins for the deep treatment of low-concentration emulsified oils, particularly in terms of dynamic pressure-controlled green pore-forming processes, improved emulsified oil treatment efficiency, multi-mechanism synergistic adsorption, and long-term cycling stability. Specifically, existing technologies have not yet proposed a method for preparing a novel composite microsphere adsorption resin that integrates green pore formation with a eutectic solvent, in-situ embedding of intercalated zirconium hydrogen phosphate dihydrate, and a dual "hydrophobic + electrostatic" adsorption mechanism. Therefore, there is an urgent need to develop a novel oil-water separation resin with excellent hydrophobic properties, stable regeneration, and selective recognition capabilities for different types of emulsions, specifically for the deep purification of low-concentration emulsified oils. Summary of the Invention

[0004] To address the problems of low adsorption capacity, poor adsorption selectivity, and weak regeneration stability of existing adsorption resins in treating low-concentration emulsified oily wastewater, this invention proposes a suspension polymerization process based on periodic pressure fluctuation-induced ordered pore formation, combined with in-situ embedding of organically modified zirconium hydrogen phosphate dihydrate, to construct a high-performance porous adsorption material with a biomimetic micro / nano rough interface. The oil-water separation material prepared by this method utilizes a low-eutectic solvent and high-pressure nitrogen microbubbles for synergistic pore formation, replacing traditional toxic organic pore-forming agents. Simultaneously, quaternary ammonium salt intercalation modification of zirconium hydrogen phosphate dihydrate is used to achieve its uniform dispersion in the resin matrix. Furthermore, a one-step suspension polymerization process is employed to construct a material with a high specific surface area >900 m². 2This invention utilizes a multifunctional composite resin with a micropore size of <8 nm and a dual-mode adsorption capacity of "hydrophobicity + electrostatic separation," achieving micropore size matching the emulsified oil droplet size, which facilitates the rapid diffusion and absorption of emulsified oil molecules. This invention solves key technical problems in existing technologies, such as poor environmental friendliness, insufficient adsorption depth of emulsified oil, a single adsorption mechanism, and weak regeneration stability. When the porous material of this invention is applied to the deep adsorption treatment of produced water containing emulsified and dissolved oil in oilfields with an oil content ≤200ppm, the effluent concentration is ≤10ppm. After 5 cycles, the adsorption retention rate is higher than 94%, demonstrating high stability and repeatability.

[0005] In a first aspect, the present invention provides a method for preparing a biomimetic micro / nano rough surface porous material for deep removal of low-concentration emulsified oil, which is achieved by the following technical solution.

[0006] A method for preparing a biomimetic micro / nano rough surface porous material for deep removal of low-concentration emulsified oil includes the following steps: S1. Modification treatment of zirconium hydrogen phosphate dihydrate: Organic modification was achieved by inserting hexadecyltrimethylammonium bromide into the interlayer of zirconium hydrogen phosphate dihydrate; S2. Suspension polymerization a. Mix deionized water with the dispersant and stir until completely dissolved to obtain the aqueous phase; b. Sonicate the oil phase mixture containing divinylbenzene, polyhydroxy acrylate, azobisisobutyronitrile, the organic modified zirconium hydrogen phosphate dihydrate obtained in step S1, and the eutectic solvent for 30-60 minutes to form a stable suspension. c. Add the oil phase obtained in step S2b dropwise to the aqueous phase obtained in step S2a. Stir until stable emulsion droplets are formed, then introduce nitrogen gas and gradually increase the pressure to 0.2-1.5 MPa while simultaneously raising the temperature to 60-80℃ to initiate polymerization. When the temperature reaches 60℃, perform periodic pressure fluctuations of depressurization and repressurization every 20-40 minutes (pressure fluctuations promote the diffusion of the pore-forming agent and the adjustment of the pore wall structure). After depressurizing to 0.2 MPa, slowly increase the pressure back to 1.0-1.5 MPa, with each cycle lasting 2-5 minutes. Perform 5-15 pressure cycles in total, maintaining a uniform temperature increase to 60-80℃ during this period. After completing the pressure cycles, maintain a constant pressure of 1.5 MPa and continue the reaction for a total time of 6-10 hours. After the reaction is complete, release the pressure to atmospheric pressure at a uniform rate of 0.1 MPa / min, remove the product, filter it, and wash it sequentially with ethanol and deionized water at 50-60℃ until the conductivity is < 10. μS / cm, vacuum drying yields white to light gray spherical porous materials.

[0007] Further, in step S1, the modification treatment method of the zirconium hydrogen phosphate dihydrate is as follows: zirconium hydrogen phosphate dihydrate powder is added to a hexadecyltrimethylammonium bromide ethanol solution, ultrasonically dispersed, stirred and refluxed at 70℃-80℃ for 6-10h, and after the reaction is completed, filtered, washed, and vacuum dried to obtain organically modified zirconium hydrogen phosphate dihydrate.

[0008] Furthermore, the concentration of hexadecyltrimethylammonium bromide in the ethanol solution is 0.03-0.2 mol / L, and the concentration of zirconium hydrogen phosphate dihydrate is 0.03-0.12 mol / L. Preferably, the concentration of hexadecyltrimethylammonium bromide in the ethanol solution is 0.05-0.15 mol / L, and the concentration of zirconium hydrogen phosphate dihydrate is 0.05-0.1 mol / L.

[0009] Furthermore, zirconium hydrogen phosphate dihydrate powder was added to a hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30-60 minutes.

[0010] Preferably, zirconium hydrogen phosphate dihydrate is dispersed in a hexadecyltrimethylammonium bromide ethanol solution and then stirred and refluxed at 70-78°C for 8-10 hours.

[0011] Furthermore, in step S2a, the concentration of the dispersant in the aqueous phase is 0.5-1 wt%; the dispersant is a mixture of hydroxypropyl cellulose and sodium chloride, and the mass ratio of sodium chloride to hydroxypropyl cellulose is 6:(1-3).

[0012] Furthermore, in step S2b, the polyhydroxy acrylate is selected from one or more of the following substances in any proportion: trimethylolpropane triacrylate, pentaerythritol tetraacrylate, and dimethicone glycerol, used to enhance the hydrophobicity and affinity for oil molecules of the material. Preferably, the polyhydroxy acrylate is selected from one or two of the following substances: trimethylolpropane triacrylate or pentaerythritol tetraacrylate.

[0013] Furthermore, in step S2b, the eutectic solvent is a system composed of choline chloride and urea in a molar ratio of 1:1.5-2, without the addition of any other organic porogens. The porous structure of this invention is formed by the combined regulation of the eutectic solvent and periodic nitrogen pressure fluctuations.

[0014] Further, in step S2b, the amount of organically modified zirconium hydrogen phosphate dihydrate is 5-15 wt% of the total monomer mass, the amount of divinylbenzene is 50-80 wt% of the total monomer mass, and the amount of azobisisobutyronitrile is 1.6-3.5 wt% of the total monomer mass; the amount of eutectic solvent is 40-100% of the total monomer mass. Preferably, the amount of organically modified zirconium hydrogen phosphate dihydrate is 6-12 wt% of the total monomer mass; the amount of divinylbenzene is preferably 64-77 wt% of the total monomer mass; and the amount of eutectic solvent is preferably 40-60% of the total monomer mass.

[0015] Furthermore, in step S2c, the volume ratio of the water and oil phases is (5-7):1.

[0016] Preferably, in step S2c, a pressure cycle from 0.2 MPa to 1.0-1.5 MPa is performed every 30-40 minutes during the polymerization process, with each cycle lasting 2-4 minutes, for a total of 6-10 pressure cycles. The reaction temperature is 70-80°C, and the total time is 6-8 hours.

[0017] Secondly, the present invention provides a biomimetic micro / nano rough surface porous material for deep removal of low-concentration emulsified oil, which is achieved by the following technical solution.

[0018] A biomimetic micro / nano rough surface porous material prepared by the above preparation method for deep removal of low-concentration emulsified oil.

[0019] By employing the above technical solutions, the biomimetic micro / nano rough surface porous material of this invention achieves zero-organic pore formation and a low-VOC process through the synergistic pore formation of a eutectic solvent and high-pressure nitrogen microbubbles. Simultaneously, it utilizes quaternary ammonium salt intercalation to modify zirconium hydrogen phosphate dihydrate, achieving its uniform dispersion in a resin matrix. Furthermore, it is constructed through one-step suspension polymerization, resulting in a material with a high specific surface area >900 m². 2 This multifunctional composite resin, characterized by its low viscosity ( / g), narrow pore size (<8 nm), and dual-mode adsorption capacity (hydrophobic + electrostatic), achieves micropore size matching with emulsified oil droplet size. It can be used for deep purification of emulsified wastewater with influent oil concentration ≤200 ppm, reducing the effluent oil concentration to ≤10 ppm. After the resin becomes saturated, it is regenerated by low-pressure steam backwashing. The regenerated resin can be used continuously for at least 5 times, maintaining an adsorption efficiency of over 94%.

[0020] This application has the following beneficial effects: This invention employs a two-step synthesis method to provide a biomimetic micro / nano rough surface porous adsorption resin based on a dynamically pressure-controlled pore-forming mechanism. It integrates a dynamic pressure-controlled green pore-forming process with in-situ embedding of intercalated modified zirconium hydrogen phosphate dihydrate to form a novel composite adsorption resin with a dual adsorption mechanism. The resin exhibits superior pore structure and a BET specific surface area >900 m².2 / g, with an average pore size <8 nm, and BJH desorption curves indicating the presence of numerous slit-type mesopores and good connectivity; biomimetic rough interface formation creates a charged rough surface micro-nano composite structure. When emulsified oil comes into contact with the porous material, demulsification is achieved under the electrostatic effect of surface charge, rapidly capturing the oil phase. The oil phase then autonomously permeates through the porous material via the rough surface and capillary action, while water in the emulsified oil is retained by the hydrophobicity of the porous material, thus achieving directional demulsification and adsorption of emulsified oil droplets. This invention can be applied to the deep adsorption treatment of produced water from oilfields containing emulsified and dissolved oil with an oil content <200 ppm. Even after five steam regeneration cycles, the separation efficiency of the oil-water emulsion remains >94%, demonstrating high stability and repeatability. Attached Figure Description

[0021] Figure 1 This is the N2 adsorption-desorption isotherm of the product prepared in Example 1 of this invention; Figure 2 This is a scanning electron microscope image of the rough surface of the product prepared in Embodiment 1 of the present invention. Detailed Implementation

[0022] This invention uses divinylbenzene and polyhydroxy acrylate monomers as the matrix, and is prepared by eutectic solvent and high-pressure nitrogen gas. The pores are induced by periodic pressure fluctuations to form a highly interconnected open network. Organically modified zirconium hydrogen phosphate dihydrate nanoparticles are embedded in situ inside the resin material skeleton, forming an oleophilic and hydrophobic porous structure with a biomimetic nanocomposite rough interface and surface charge within the resin skeleton, thereby achieving in-situ electrostatic demulsification and separation.

[0023] The present patent application will be further described below with reference to the accompanying drawings and embodiments.

[0024] The following embodiments of this application use zirconium hydrogen phosphate dihydrate (99% purity), pentaerythritol tetraacrylate (97% purity), trimethylolpropane triacrylate (95% purity), hydroxypropyl cellulose (2% viscosity: 100000 mPa.s), divinylbenzene (80% Mixture of Isomers, containing 0.1% TBC stabilizer), choline chloride (99% purity), and urea (99% purity) purchased from Shanghai Maclean Biochemical Technology Co., Ltd. Example 1

[0025] 7.2 g of zirconium hydrogen phosphate dihydrate powder was added to 300 ml of 0.1 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 70 °C for 8 hours to allow hexadecyltrimethylammonium bromide to intercalate between the zirconium hydrogen phosphate dihydrate layers. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0026] In a 1L reactor, 2.77g sodium chloride, 0.93g hydroxypropyl cellulose and 5.7g organically modified zirconium hydrogen phosphate dihydrate were dissolved in 740g water and stirred until completely dissolved. A mixture of 66.0 g divinylbenzene, 28.3 g pentaerythritol tetraacrylate, 52.0 g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:2), and 1.9 g azobisisobutyronitrile (AIBN) was sonicated at room temperature for 30 minutes to form a stable suspension. This suspension was then slowly added dropwise to the aqueous phase and placed in a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.5 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.5 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. A total of 6 pressure cycles were performed, during which the temperature was kept at a constant rate and increased to 80 °C. After the pressure cycle was completed, the temperature was maintained at 1.5 MPa. The reaction was continued at a constant pressure of MPa for a total time of 6 hours. After the reaction was completed, the pressure was uniformly reduced to atmospheric pressure at a rate of 0.1 MPa / min to avoid abrupt structural changes. The product was removed, filtered, and washed successively with ethanol and 60°C hot water until the conductivity of the effluent was < 10 μS / cm to ensure complete removal of the eutectic solvent. Vacuum drying yielded white to light gray spherical particles with a surface area of ​​903 m². 2 / g, pore size 6.83nm, see Table 1.

[0027] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the chromatography column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After continuous operation for 20 hours, samples were taken for testing. The oil concentration in the effluent was 7.6 ppm, with a removal rate >96%. After adsorption saturation, the surface free water phase was removed by pre-rinsing with 80℃ hot water for 30 minutes. Regeneration was then performed with 0.1 MPa saturated steam before reuse. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was 9.2 ppm, with a removal rate >95.2%. Example 2

[0028] 4.5 g of zirconium hydrogen phosphate dihydrate powder was added to 300 ml of 0.05 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 77 °C for 8 hours to allow hexadecyltrimethylammonium bromide to intercalate between the zirconium hydrogen phosphate dihydrate layers. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0029] In a 1L reactor, 2.63g of sodium chloride, 0.87g of hydroxypropyl cellulose and 3.8g of organically modified zirconium hydrogen phosphate dihydrate were dissolved in 700g of water and stirred until completely dissolved. A mixture of 41.3 g divinylbenzene, 22.5 g pentaerythritol tetraacrylate, 35.2 g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:2), and 1.05 g azobisisobutyronitrile (AIBN) was sonicated at room temperature for 30 minutes to form a stable suspension. This suspension was then slowly added dropwise to the aqueous phase and placed in a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.5 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.5 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. A total of 6 pressure cycles were performed, during which the temperature was kept at a constant rate and increased to 80 °C. After the pressure cycle was completed, the temperature was maintained at 1.5 MPa. The reaction was continued at a constant pressure of MPa for a total time of 6 hours. After the reaction was completed, the pressure was uniformly reduced to atmospheric pressure at a rate of 0.1 MPa / min to avoid abrupt structural changes. The product was removed, filtered, and washed successively with ethanol and 60°C hot water until the conductivity was < 10 μS / cm to ensure complete removal of the eutectic solvent. Vacuum drying yielded white to light gray spherical particles with a surface area of ​​977 m². 2 / g, pore size 6.35nm, see Table 1.

[0030] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After 20 hours of continuous operation, samples were taken for testing. The oil concentration in the effluent was 5.5 ppm, with a removal rate >97.1%. After adsorption saturation, the surface free water phase was removed by pre-rinsing with 80℃ hot water for 30 minutes. The water was then regenerated with 0.1 MPa saturated steam and put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was still 9.4 ppm, with a removal rate >95.1%. Example 3

[0031] 9.0 g of zirconium hydrogen phosphate dihydrate powder was added to 300 ml of 0.15 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 75 °C for 10 hours to allow hexadecyltrimethylammonium bromide to intercalate between the zirconium hydrogen phosphate dihydrate layers. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0032] In a 1L reactor, 2.32g of sodium chloride, 1.16g of hydroxypropyl cellulose and 6.8g of organically modified zirconium hydrogen phosphate dihydrate were dissolved in 696g of water and stirred until completely dissolved. A mixture of 65.0 g divinylbenzene, 20.2 g pentaerythritol tetraacrylate, 51.0 g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:2), and 3.0 g azobisisobutyronitrile (AIBN) was sonicated at room temperature for 30 minutes to form a stable suspension. This suspension was then slowly added dropwise to the aqueous phase and placed in a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.0 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.0 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. A total of 10 pressure cycles were performed, during which the temperature was kept at a constant rate and increased to 80 °C. After the pressure cycle was completed, the temperature was maintained at 1.5 °C. The reaction was continued at a constant pressure of MPa for a total time of 8 hours. After the reaction was completed, the pressure was uniformly reduced to atmospheric pressure at a rate of 0.1 MPa / min. The product was removed, filtered, and washed successively with ethanol and 50°C hot water until the conductivity of the effluent was < 10 μS / cm, ensuring complete removal of the eutectic solvent. The product was then vacuum dried to obtain white to light gray spherical particles with a surface area of ​​1147 m². 2 / g, pore size 5.82nm, see Table 1.

[0033] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After 20 hours of continuous operation, samples were taken for testing. The oil concentration in the effluent was 3.7 ppm, with a removal rate >98.1%. After adsorption saturation, the water was pre-washed with 80℃ hot water for 30 minutes to remove the surface free water phase. After regeneration with 0.1 MPa saturated steam, the water was put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was still 5.3 ppm, with a removal rate >97.2%. Example 4

[0034] 9.0 g of zirconium hydrogen phosphate dihydrate powder was added to 300 ml of 0.1 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 70 °C for 8 hours to allow hexadecyltrimethylammonium bromide to insert into the interlayer of zirconium hydrogen phosphate dihydrate. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0035] In a 1L reactor, 2.91g of sodium chloride, 0.45g of hydroxypropyl cellulose and 9.4g of organically modified zirconium hydrogen phosphate dihydrate were dissolved in 671g of water and stirred until completely dissolved. A mixture of 66.0 g divinylbenzene, 28.3 g trimethylolpropane triacrylate, 38.0 g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:2), and 1.9 g azobisisobutyronitrile (AIBN) was sonicated at room temperature for 30 minutes to form a stable suspension. This suspension was then slowly added dropwise to the aqueous phase and placed in a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.3 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.3 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. A total of 8 pressure cycles were performed, during which the temperature was kept at a constant rate of increase to 80 °C. After the pressure cycle was completed, the temperature was maintained at 1.5 °C. The reaction was continued at a constant pressure of MPa for a total time of 6 hours. After the reaction was completed, the pressure was uniformly reduced to atmospheric pressure at a rate of 0.1 MPa / min. The product was removed, filtered, and washed successively with ethanol and 60°C hot water until the conductivity of the effluent was < 10 μS / cm, ensuring complete removal of the eutectic solvent. The product was then vacuum dried to obtain white to light gray spherical particles with a surface area of ​​1098 m². 2 / g, pore size 5.97nm, see Table 1.

[0036] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After 20 hours of continuous operation, samples were taken for testing. The oil concentration in the effluent was 3.9 ppm, with a removal rate >97.9%. After adsorption saturation, the surface free water phase was removed by pre-rinsing with 80℃ hot water for 30 minutes. The water was then regenerated with 0.1 MPa saturated steam and put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was 7.1 ppm, with a removal rate >96.3%. Example 5

[0037] 10.5 g of zirconium hydrogen phosphate dihydrate powder was added to 350 ml of 0.1 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 70 °C for 8 hours to allow hexadecyltrimethylammonium bromide to intercalate between the zirconium hydrogen phosphate dihydrate layers. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0038] In a 1L reactor, 5.67g of sodium chloride, 1.73g of hydroxypropyl cellulose and 11.3g of organically modified zirconium hydrogen phosphate dihydrate were dissolved in 740g of water and stirred until completely dissolved. A mixture of 66.0 g divinylbenzene, 28.3 g pentaerythritol tetraacrylate, 52.0 g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:2), and 1.9 g azobisisobutyronitrile (AIBN) was sonicated at room temperature for 30 minutes to form a stable suspension. This suspension was then slowly added dropwise to the aqueous phase and placed in a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.5 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.5 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. A total of 6 pressure cycles were performed, during which the temperature was kept at a constant rate and increased to 80 °C. After the pressure cycle was completed, the temperature was maintained at 1.5 MPa. The reaction was continued at a constant pressure of MPa for a total time of 6 hours. After the reaction was completed, the pressure was uniformly reduced to atmospheric pressure at a rate of 0.1 MPa / min. The product was removed, filtered, and washed successively with ethanol and 60°C hot water until the conductivity of the effluent was < 10 μS / cm, ensuring complete removal of the eutectic solvent. The product was then vacuum dried to obtain white to light gray spherical particles with a surface area of ​​926 m². 2 / g, pore size 2.3nm, see Table 1.

[0039] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After 20 hours of continuous operation, samples were taken for testing. The oil concentration in the effluent was 8.8 ppm, with a removal rate >95.4%. After adsorption saturation, the surface free water phase was removed by pre-rinsing with 80℃ hot water for 30 minutes. The water was then regenerated with 0.1 MPa saturated steam and put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was 10.3 ppm, with a removal rate >94.6%. Example 6

[0040] 7.2 g of zirconium hydrogen phosphate dihydrate powder was added to 300 ml of 0.1 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 70 °C for 8 hours to allow hexadecyltrimethylammonium bromide to intercalate between the zirconium hydrogen phosphate dihydrate layers. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0041] In a 1L reactor, 6.35g of sodium chloride, 1.05g of hydroxypropyl cellulose and 5.7g of organically modified zirconium hydrogen phosphate dihydrate were dissolved in 740g of water and stirred until completely dissolved. A mixture of 66.0 g divinylbenzene, 28.3 g pentaerythritol tetraacrylate, 52.0 g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:2), and 1.9 g azobisisobutyronitrile (AIBN) was sonicated at room temperature for 30 minutes to form a stable suspension. This suspension was then slowly added dropwise to the aqueous phase and placed in a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.0 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.0 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. A total of 6 pressure cycles were performed, during which the temperature was kept at a constant rate and increased to 80 °C. After the pressure cycle was completed, the temperature was maintained at 1.5 °C. The reaction was continued at a constant pressure of MPa for a total time of 6 hours. After the reaction was completed, the pressure was uniformly reduced to atmospheric pressure at a rate of 0.1 MPa / min to avoid abrupt structural changes. The product was removed, filtered, and washed successively with ethanol and 60°C hot water until the conductivity of the effluent was < 10 μS / cm to ensure complete removal of the eutectic solvent. Vacuum drying yielded white to light gray spherical particles with a surface area of ​​972 m². 2 / g, pore size 6.16nm, see Table 1.

[0042] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After 20 hours of continuous operation, samples were taken for testing. The oil concentration in the effluent was 4.8 ppm, with a removal rate >97.5%. After adsorption saturation, the water was pre-washed with 80℃ hot water for 30 minutes to remove the surface free water phase. After regeneration with 0.1 MPa saturated steam, the water was put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was 8.7 ppm, with a removal rate >95.5%. Example 7

[0043] 7.2 g of zirconium hydrogen phosphate dihydrate powder was added to 300 ml of 0.1 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 70 °C for 8 hours to allow hexadecyltrimethylammonium bromide to intercalate between the zirconium hydrogen phosphate dihydrate layers. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0044] In a 1L reactor, 6.35g of sodium chloride, 1.05g of hydroxypropyl cellulose and 5.7g of organically modified zirconium hydrogen phosphate dihydrate were dissolved in 740g of water and stirred until completely dissolved. A mixture of 66.0 g divinylbenzene, 28.3 g pentaerythritol tetraacrylate, 52.0 g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:1.5), and 1.9 g azobisisobutyronitrile (AIBN) was sonicated at room temperature for 30 minutes to form a stable suspension. This suspension was then slowly added dropwise to the aqueous phase and placed into a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.5 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.5 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. A total of 6 pressure cycles were performed, during which the temperature was kept at a constant rate and increased to 80 °C. After the pressure cycle was completed, the temperature was maintained at 1.5 MPa. The reaction was continued at a constant pressure of MPa for a total time of 6 hours. After the reaction was completed, the pressure was uniformly reduced to atmospheric pressure at a rate of 0.1 MPa / min to avoid abrupt structural changes. The product was removed, filtered, and washed successively with ethanol and 60°C hot water until the conductivity of the effluent was < 10 μS / cm to ensure complete removal of the eutectic solvent. Vacuum drying yielded white to light gray spherical particles with a surface area of ​​946 m². 2 / g, pore size 4.8nm, see Table 1.

[0045] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After 20 hours of continuous operation, samples were taken for testing. The oil concentration in the effluent was 2.5 ppm, with a removal rate >98.6%. After adsorption saturation, the water was pre-washed with 80℃ hot water for 30 minutes to remove the surface free water phase. After regeneration with 0.1 MPa saturated steam, the water was put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was 9.3 ppm, with a removal rate >95.1%.

[0046] Comparative Example 1 7.2 g of zirconium hydrogen phosphate dihydrate powder was added to 300 ml of 0.1 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 70 °C for 8 hours to allow hexadecyltrimethylammonium bromide to intercalate between the zirconium hydrogen phosphate dihydrate layers. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0047] In a 1L reactor, 2.77g sodium chloride, 0.93g hydroxypropyl cellulose, and 5.7g organically modified zirconium hydrogen phosphate dihydrate were dissolved in 740g water and stirred until completely dissolved. An oil-phase mixture containing 66.0g divinylbenzene, 28.3g pentaerythritol tetraacrylate, 52.0g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:2), and 1.9g azobisisobutyronitrile was sonicated at room temperature for 30 minutes to form a stable suspension, which was then slowly added dropwise to the aqueous phase and added to the reactor. After forming stable emulsion droplets under mechanical stirring, the temperature was raised to 80℃ for polymerization for 6 hours. After the reaction, the product was removed, filtered, and washed successively with ethanol and 60℃ hot water until the conductivity of the effluent was < 10 μS / cm, ensuring complete removal of the eutectic solvent. Vacuum drying yielded white to light yellow spherical particles with a surface area of ​​601 m². 2 / g, pore size 3.79nm, see Table 1.

[0048] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the chromatography column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After continuous operation for 20 hours, samples were taken for testing. The oil concentration in the effluent was 26 ppm, with a removal rate >86.5%. After adsorption saturation, the surface free water phase was removed by pre-rinsing with 80℃ hot water for 30 minutes. After regeneration with 0.1 MPa saturated steam, the system was put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was 34.2 ppm, with a removal rate >82.2%.

[0049] Comparative Example 2 In a 1L reactor, dissolve 2.77g sodium chloride and 0.93g hydroxypropyl cellulose in 740g water and stir until completely dissolved. A mixture of oil phase solutions containing 66.0 g divinylbenzene, 28.3 g pentaerythritol tetraacrylate, 1.9 g azobisisobutyronitrile, and 52.0 g eutectic solvent (composed of choline chloride and urea in a molar ratio of 1:2) was sonicated at room temperature for 30 minutes to form a stable suspension. This suspension was then slowly added dropwise to the aqueous phase and placed in a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.5 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.5 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. A total of 6 pressure cycles were performed, during which the temperature was kept at a constant rate and increased to 80 °C. After the pressure cycle was completed, the temperature was maintained at 1.5 MPa. The reaction was continued at a constant pressure of MPa for a total time of 6 hours. After the reaction was completed, the pressure was uniformly reduced to atmospheric pressure at a rate of 0.1 MPa / min to avoid abrupt structural changes. The product was removed, filtered, and washed successively with ethanol and 60°C hot water until the conductivity of the effluent was < 10 μS / cm to ensure complete removal of the eutectic solvent. Vacuum drying yielded white to light gray spherical particles with a surface area of ​​691 m². 2 / g, pore size 7.40nm, see Table 1.

[0050] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the chromatography column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After continuous operation for 20 hours, samples were taken for testing. The oil concentration in the effluent was 19 ppm, with a removal rate >90%. After adsorption saturation, the surface free water phase was removed by pre-rinsing with 80℃ hot water for 30 minutes. After regeneration with 0.1 MPa saturated steam, the system was put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was 22.6 ppm, with a removal rate >88.2%.

[0051] Comparative Example 3 7.2 g of zirconium hydrogen phosphate dihydrate powder was added to 300 ml of 0.1 mol / L hexadecyltrimethylammonium bromide ethanol solution and ultrasonically dispersed for 30 minutes. The solution was then transferred to a round-bottom flask and stirred under reflux at 70 °C for 8 hours to allow hexadecyltrimethylammonium bromide to intercalate between the zirconium hydrogen phosphate dihydrate layers. After the reaction was complete, the mixture was filtered, washed with ethanol to remove free surface modifiers, and vacuum dried at 60 °C for 14 hours to achieve interlayer organic intercalation modification, resulting in organically modified zirconium hydrogen phosphate dihydrate. This provides an organophilic functional filler that improves dispersion stability.

[0052] In a 1L reactor, 2.77g sodium chloride, 0.93g hydroxypropyl cellulose and 5.7g organically modified zirconium hydrogen phosphate dihydrate were dissolved in 740g water and stirred until completely dissolved. A stable suspension was formed by sonicating an oil-phase mixture containing 66.0 g divinylbenzene, 28.3 g pentaerythritol tetraacrylate, 52.0 g toluene, and 1.9 g azobisisobutyronitrile (AIBN) for 30 minutes at room temperature. This suspension was then slowly added dropwise to the aqueous phase and placed into a sealed reactor. After forming stable emulsion droplets under mechanical stirring, nitrogen gas was introduced and the pressure was gradually increased to 1.5 MPa while the temperature was raised to 60 °C to initiate polymerization. At 60 °C, a periodic pressure fluctuation of "depressurization-repressurization" was performed every 30 minutes. The pressure was depressurized to 0.2 MPa within 2 minutes and then repressurized back to 1.5 MPa within 2 minutes. This pressure fluctuation promoted the diffusion of the pore-forming agent and the adjustment of the pore wall structure, achieving a "self-organized" ordered porous network. Six pressure cycles were performed, during which the temperature was kept at a constant rate and increased to 80 °C. After the pressure cycle was completed, a constant pressure of 1.5 MPa was maintained, and the reaction continued for a total time of 6 hours. After the reaction was completed, the solution was discharged at 0.1... The pressure was uniformly reduced to atmospheric pressure at a rate of MPa / min to avoid abrupt structural changes. The product was then removed, filtered, and washed successively with ethanol and 60°C hot water until the conductivity of the effluent was < 10 μS / cm, ensuring complete removal of the eutectic solvent. Vacuum drying yielded white to light gray spherical particles with a surface area of ​​857 m². 2 / g, pore size 5.66nm, see Table 1.

[0053] Using a chromatography column with a diameter of 1.5 cm and a length of 30 cm as the adsorption filtration device, 30 g of spherical oil-water separation material was packed into the chromatography column. Produced water from an oilfield containing emulsified oil with an oil content of 192 ppm was subjected to adsorption filtration treatment. The water flow rate was controlled at 5 BV / h. After continuous operation for 20 hours, samples were taken for testing. The oil concentration in the effluent was 8.9 ppm, with a removal rate >95.3%. After adsorption saturation, the surface free water phase was removed by pre-rinsing with 80℃ hot water for 30 minutes. After regeneration with 0.1 MPa saturated steam, the system was put back into use. After 5 cycles, the oil concentration in the effluent at the end of the 5th cycle was 14.8 ppm, with a removal rate >92.3%.

[0054] Table 1. Pore structure of oil-water separation materials The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a biomimetic micro / nano rough surface porous material for deep removal of low-concentration emulsified oil, characterized in that: Includes the following steps: S1. Modification treatment of zirconium hydrogen phosphate dihydrate: Organic modification was achieved by inserting hexadecyltrimethylammonium bromide into the interlayer of zirconium hydrogen phosphate dihydrate; S2. Suspension polymerization a. Mix deionized water with the dispersant and stir until completely dissolved to obtain the aqueous phase; b. Sonicate the oil phase mixture containing divinylbenzene, polyhydroxy acrylate, azobisisobutyronitrile, the organic modified zirconium hydrogen phosphate dihydrate obtained in step S1, and the eutectic solvent for 30-60 minutes to form a stable suspension. c. Add the oil phase obtained in step S2b dropwise to the aqueous phase obtained in step S2a. Stir until a stable emulsion droplet is formed, then introduce nitrogen gas and gradually increase the pressure to 0.2-1.5 MPa. Simultaneously, raise the temperature to 60-80℃ to initiate polymerization. When the temperature reaches 60℃, perform periodic pressure fluctuations of depressurization and repressurization every 20-40 minutes. After depressurization to 0.2 MPa, slowly increase the pressure back to 1.0-1.5 MPa. Each cycle lasts 2-5 minutes, and a total of 5-15 pressure cycles are performed. During this period, maintain a uniform temperature increase to 60-80℃. After the pressure cycle is completed, maintain a constant pressure of 1.5 MPa and continue the reaction for a total time of 6-10 hours. After the reaction is completed, release the pressure to atmospheric pressure at a uniform rate of 0.1 MPa / min, remove the product, filter it, and wash it successively with ethanol and water until the conductivity is < 10 μS / cm. Vacuum dry to obtain a porous material.

2. The preparation method according to claim 1, characterized in that: In step S1, the modification treatment method of zirconium hydrogen phosphate dihydrate is as follows: zirconium hydrogen phosphate dihydrate powder is added to a hexadecyltrimethylammonium bromide ethanol solution, ultrasonically dispersed, stirred and refluxed at 70℃-80℃ for 6-10h, and after the reaction is completed, filtered, washed, and vacuum dried to obtain organic modified zirconium hydrogen phosphate dihydrate.

3. The preparation method according to claim 2, characterized in that: The concentration of hexadecyltrimethylammonium bromide in the ethanol solution is 0.03-0.2 mol / L, and the concentration of zirconium hydrogen phosphate dihydrate is 0.03-0.12 mol / L.

4. The preparation method according to claim 1, characterized in that: In step S2a, the concentration of the dispersant in the aqueous phase is 0.5-1 wt%; the dispersant is a mixture of hydroxypropyl cellulose and sodium chloride, and the mass ratio of sodium chloride to hydroxypropyl cellulose is 6:(1-3).

5. The preparation method according to claim 1, characterized in that: In step S2b, the polyhydroxy acrylate is selected from one or more of the following substances in any proportion: trimethylolpropane triacrylate, pentaerythritol tetraacrylate, and dimethacrylate.

6. The preparation method according to claim 1, characterized in that: In step S2b, the eutectic solvent is a system composed of choline chloride and urea in a molar ratio of 1:1.5-2.

7. The preparation method according to claim 1, characterized in that: In step S2b, the amount of organic modified zirconium hydrogen phosphate dihydrate is 5-15 wt% of the total monomer mass; the amount of divinylbenzene is 50-80 wt% of the total monomer mass; the amount of azobisisobutyronitrile is 1.6-3.5 wt% of the total monomer mass; and the amount of eutectic solvent is 40-100% of the total monomer mass.

8. The preparation method according to claim 1, characterized in that: In step S2c, the volume ratio of the water and oil phases is (5-7):

1.

9. A biomimetic micro / nano rough surface porous material for deep removal of low-concentration emulsified oil, prepared by any of the preparation methods described in claims 1-8.

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