Hydrophobic and oleophobic silver-loaded cupric oxide sba-15 mercury removal agent imitating the cuticle structure of isopods, preparation method and application

Abstract

This invention discloses a hydrophobic and oleophobic silver-copper oxide SBA-15 mercury removal agent with a shell-like structure inspired by the skin of a snapdragon, its preparation method, and its applications, belonging to the field of mercury removal agent preparation technology. The method includes: using SBA-15 mesoporous molecular sieve as a carrier, employing a preparation strategy of first constructing a biomimetic superhydrophobic and oleophobic surface, and then confining and loading Ag-CuO; the outer surface of the mesoporous molecular sieve has a snapdragon-like micro / nano composite structure constructed through chemical etching and modified with a fluoroalkylsilane hydrophobic and oleophobic layer; Ag and CuO are confined and loaded within the mesoporous channels, where Ag provides amalgamation mercury removal activity, and CuO preferentially reacts with H2S to protect Ag from sulfur poisoning and provides additional mercury-loving sites for synergistic mercury removal. The mercury removal agent of this invention exhibits high mercury removal capacity, high wet gas efficiency, and excellent regenerability under sulfur-containing wet gas conditions. It demonstrates high capacity, high selectivity, and good regeneration stability in natural gas wet mercury removal, showing broad industrial application prospects.

Description

Technical Field

[0001] This invention relates to the field of mercury removal agent preparation technology, specifically to a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a structure similar to that of a snapdragon's skin, its preparation method, and its application. Background Technology

[0002] Mercury in natural gas not only causes liquid metal embrittlement and corrosion in pipelines and liquefaction equipment, but also poisons and deactivates catalysts, and is released into the atmosphere during combustion, causing environmental pollution. Therefore, natural gas must undergo deep mercury removal treatment before entering long-distance pipelines or liquefaction plants.

[0003] Currently, mercury removal technologies used in industry mainly fall into two categories: non-renewable chemisorption and renewable adsorption. Relevant reports on existing technologies include: Application No. 202011081533.9 discloses a mercury removal agent for natural gas and its preparation method, which is composed of a copper-based compound, carrier particles, and auxiliary components. The carrier particles are composed of a carrier skeleton and a binder. The carrier skeleton is composed of hydrated alumina, titanium dioxide, zirconium oxide, guar gum powder, urea, and carbon nanotubes. The binder is composed of guar gum powder, clay, sepiolite, and silica sol. The auxiliary component is silver sulfide. The agent is prepared by carrier particles, impregnated with copper-based compound, calcined, and then sulfided. Finally, it is reduced by reducing gas to obtain the mercury removal agent for natural gas. Application No. 202010184956.7 discloses a method for preparing a mercury removal agent for renewable natural gas. The method includes the following steps: (1) dissolving a soluble metal salt in water to form a metal salt solution; (2) impregnating alumina balls in the metal salt solution; (3) drying and heating the alumina balls after impregnation in the salt solution to decompose the metal salt impregnated on the alumina balls and generate elemental metal.

[0004] Silver-loaded molecular sieves have attracted widespread attention due to their excellent regeneration performance. However, existing technologies still have the following technical problems: First, the presence of liquid in the feed gas will significantly reduce the mercury removal capacity of silver-loaded molecular sieves, with the mercury removal capacity under humid conditions being only 63% of that under dry conditions. Second, the trace amounts of hydrogen sulfide often contained in natural gas will react with silver to form silver sulfide, leading to irreversible deactivation of silver active sites.

[0005] This shows that the existing technology needs further improvement. Summary of the Invention

[0006] One of the objectives of this invention is to provide a method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a structure inspired by the skin of a snapdragon. This method achieves functional partitioning of the surface hydrophobicity and oleophobicity with the active components within the pores by first constructing a biomimetic superhydrophobic surface and then confining and loading Ag-CuO. The method also achieves sulfur-resistant mercury removal through the synergistic effect of Ag-CuO bimetallic components, thereby improving the mercury removal capacity and regenerability.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury-removing agent with a structure similar to the skin of a snapdragon, comprising the following steps: a. Temporary pore-filling protection: Disperse SBA-15 mesoporous molecular sieve in an organic solvent, add a polymeric pore-filling agent, stir thoroughly, and then evaporate the organic solvent to allow the polymeric pore-filling agent to fill the mesoporous channels of SBA-15. b. Biomimetic superhydrophobic modification of the outer surface: The SBA-15 obtained after temporary pore filling protection in step a is placed in an alkaline reaction solution containing silicon precursor, and SiO2 nanoneedle arrays are grown on its outer surface by sol-gel method to construct a micro-nano composite structure inspired by the snaptail worm; then the obtained product is placed in a chemical vapor deposition reactor, and fluorination modification is performed by chemical vapor deposition using fluoroalkylsilane as a precursor to obtain SBA-15 with a superhydrophobic surface; c. Removal of polymeric pore filler: The SBA-15 with superhydrophobic surface obtained in step b is heat-treated to remove the polymeric pore filler, thereby opening the mesoporous channels; the heat treatment also causes some of the fluorinated layer to decompose. d. Ag-CuO confined loading and fluoride remediation: The product obtained in step c was impregnated in a mixed solution containing copper salt and silver precursor, and Cu² was added using an equal-volume impregnation method. + and Ag + The Ag-CuO@SBA-15 composite was obtained by introducing the material into the mesoporous channels of SBA-15, followed by drying and calcination. Subsequently, the obtained material was placed in a vapor deposition reactor for secondary vapor-phase fluorination deposition to repair the fluorinated layer decomposed in step c and restore the superhydrophobic properties of the outer surface.

[0008] The beneficial technical effects directly brought about by the above technical solution are as follows: (1) The mesopore retention effect directly resulting from the temporary pore-filling protection strategy. The polymeric pore-filling agent pre-fills the SBA-15 mesopore channels, effectively protecting the SBA-15 mesopores from blockage during subsequent SiO2 nanoneedle growth and fluorination modification. After removing the polymeric pore-filling agent, the mesopore volume retention rate is >90%, ensuring Hg... 0 It can smoothly enter the pores and contact the active sites. Comparative data show that without pore-filling protection, the mesopore volume loss rate exceeds 70%, and the mercury removal capacity decreases by more than 60%.

[0009] (2) Biomimetic micro / nano rough structure directly resulting from SiO2 nanoneedle array. SiO2 nanoneedle arrays with needle lengths of 50-200 nm, diameters of 10-30 nm, and spacing of 30-80 nm were grown on the outer surface of SBA-15 using the sol-gel method, mimicking the micro / nano structure of springtail epidermis. This structure traps an air layer, directly reducing the contact area between the aqueous and oil phases and the material surface, placing the droplets in a Cassie-Baxter state. The enhanced surface roughness provides a larger specific surface area and more bonding sites for subsequent fluorination modification, increasing the grafting density of the hydrophobic and oleophobic layers by 30-50%.

[0010] (3) The anti-fouling ability directly brought about by the hydrophobic and oleophobic layer of fluoroalkylsilane. By chemical vapor deposition, fluoroalkylsilane is covalently bonded to the surface of SiO2 nanoneedles, which reduces the surface free energy of the material from 40-50 mN / m to 10-15 mN / m, directly resulting in an increase in the water contact angle from 32° to more than 150° and an increase in the oil contact angle from <10° to more than 110°; the low surface energy layer directly blocks the adsorption of polar and non-polar molecules, while maintaining a high affinity for mercury.

[0011] (4) The synergistic effect of biomimetic micro / nano structures and fluorination directly results in superhydrophobic properties. The physical hydrophobicity of the SiO2 nanoneedle array and the chemical hydrophobicity of the fluoroalkylsilane directly combine to achieve a water contact angle exceeding 150°, reaching superhydrophobicity; and an oil contact angle exceeding 110°, reaching oleophobicity. Comparative data show that the water contact angle without nanoneedle structure and only fluorination modification is 115.3° and the oil contact angle is 68.4°, while the water contact angle is increased by 37° and the oil contact angle is increased by 50.1° after the dual treatment of nanoneedles and fluorination, confirming that there is a significant synergistic effect between the two.

[0012] (5) Synergistic process of removing pore filler and restoring fluoride. The technical problem of fluoride layer decomposition during the heat treatment of removing pore filler was identified and solved. Through a secondary fluoride replenishment step after metal loading, the superhydrophobic properties of the material's outer surface were restored. After fluoride replenishment, the water contact angle was restored to over 150°, ensuring the long-term stability of the mercury removal agent.

[0013] (6) Improved mercury removal efficiency directly resulting from Ag-CuO confined loading. Silver nanoparticles directly form silver amalgam (Ag-Hg) with mercury, achieving chemical adsorption and fixation of mercury; CuO preferentially reacts with H2S to form CuS, directly protecting Ag from sulfide poisoning, reducing the sulfide deactivation rate of Ag in H2S atmosphere from over 60% to below 5%; the generated CuS has a positive effect on Hg removal efficiency. 0 It has good affinity, provides additional adsorption sites, and works synergistically with Ag to increase the mercury removal capacity by more than 100% compared with the single silver-loaded sample.

[0014] In the preparation method of the above-mentioned hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a mimicking the skin structure of a snapdragon, in step a, the polymeric pore-filling agent is one or more of polyethylene glycol, polyvinyl alcohol, or paraffin with a molecular weight of 2000-20000, and the mass ratio of the polymeric pore-filling agent to the SBA-15 mesoporous molecular sieve is 0.5-2:1; the organic solvent is ethanol or acetone.

[0015] In the preparation method of the above-mentioned hydrophobic and oleophobic silver-copper oxide SBA-15 mercury removal agent with a mimicking the skin structure of a snapdragon, in step a, the mixture is stirred at a temperature of 45-55°C and the organic solvent is evaporated by rotary evaporation at a temperature of 55-65°C.

[0016] The preparation method of the above-mentioned hydrophobic and oleophobic silver-copper oxide SBA-15 mercury removal agent with a shell-like structure, wherein in step b, the silicon-containing precursor is tetraethoxysilane or tetramethoxysilane; the specific steps of growing SiO2 nanoneedle arrays on its outer surface by sol-gel method are as follows: the SBA-15 obtained after temporary pore filling protection in step a is placed in an ammonia reaction solution of silicon-containing precursor, the concentration of silicon-containing precursor is 0.01-0.05 M, the pH of the reaction solution is adjusted to 8-10 with ammonia, the temperature is 40-60℃, and the reaction is carried out for 6-24 hours; after filtration, washing and drying, SiO2 nanoneedle arrays are obtained.

[0017] The preparation method of the above-mentioned hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure, wherein the reaction conditions of the vapor deposition reactor are: temperature 80-120℃, vacuum degree <10 Pa, and deposition time 2-6 hours; wherein the fluoroalkylsilane is perfluorodecyltrichlorosilane, perfluorodecyltriethoxysilane or tridecafluorooctyltriethoxysilane.

[0018] In the preparation method of the above-mentioned hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a mimicking the skin structure of a snapdragon, the conditions for heat treatment to remove the polymer pore-filling agent in step c are: heat treatment at 300-400℃ for 2-4 hours in an air atmosphere.

[0019] The preparation method of the above-mentioned hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure, wherein in step d, the copper salt is copper nitrate, the silver precursor is silver ammonia solution or silver nitrate; the calcination temperature is 300-500℃, the calcination time is 2-4 hours; the secondary vapor phase fluorination deposition conditions are: temperature 80-120℃, vacuum degree <10 Pa, time 1-3 hours, and the amount of fluoroalkyl silane is 3-8% of the mass of Ag-CuO@SBA-15 composite.

[0020] Another objective of this invention is to provide a hydrophobic and oleophobic silver-copper oxide SBA-15 mercury removal agent with a resemblance to the skin structure of a snapdragon. This agent is prepared using the method described above and comprises an SBA-15 mesoporous molecular sieve and a snapdragon-like micro / nanostructure located on the outer surface of the SBA-15 mesoporous molecular sieve. The snapdragon-like micro / nanostructure is constructed using an array of SiO2 nanoneedles. The length of the SiO2 nanoneedles is 50–200 nm, the diameter is 10–30 nm, and the spacing between adjacent nanoneedles is 30–80 nm. The surface of the snapdragon-like micro / nanostructure is chemically bonded with a fluoroalkylsilane hydrophobic and oleophobic layer. Silver nanoparticles and copper oxide are confined and loaded within the mesoporous channels of the SBA-15 mesoporous molecular sieve.

[0021] Another object of the present invention is to provide the application of the above-mentioned hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure in natural gas wet mercury removal.

[0022] The above applications include: filling the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent into a fixed-bed adsorption tower to treat mercury-containing natural gas moisture. After adsorption saturation, it is oxidized and regenerated in an oxygen-containing atmosphere at 300-400℃, while gasified fluoroalkylsilane is introduced for in-situ fluorine replenishment and remediation.

[0023] Compared with the prior art, the present invention brings the following beneficial technical effects: (1) Breakthrough improvement in moisture adaptability. Existing silver-loaded molecular sieve technology suffers a significant decrease in mercury removal capacity under humid conditions, with a moisture / dry gas efficiency of only 63-64%. This invention maintains open mesopores through a temporary pore-filling protection strategy, and combines SiO2 nanoneedle arrays with fluorination modification to achieve an ultra-amphihydrophobic outer surface (water contact angle >150°, oil contact angle >110°), thereby increasing the moisture / dry gas efficiency to over 93%, a 30 percentage point improvement over existing technologies. This breakthrough allows for direct mercury removal from natural gas moisture without the need for pre-dehydration, significantly simplifying the process and reducing equipment investment and operating costs.

[0024] (2) Effective protection of mesoporous channel integrity. This invention employs a temporary pore-filling protection strategy to effectively protect the SBA-15 mesoporous channels from blockage by SiO2 nanoneedles or fluoride layers during the biomimetic coating construction process. The adsorption / diffusion channels of the mesopores can be restored after removing the pore-filling agent. Comparative examples show that without pore-filling protection, the mesoporous pore volume loss rate is >70%, and the mercury removal capacity decreases by more than 60%.

[0025] (3) Significantly improved sulfur resistance. Existing silver-loaded molecular sieves are easily poisoned by sulfidation at their silver active sites in an H2S atmosphere (sulfidation deactivation degree >60%), resulting in a significant decrease in mercury removal capacity. This invention utilizes CuO to preferentially react with H2S to generate CuS, protecting Ag from sulfidation poisoning. In an atmosphere containing 80ppm H2S, the Ag sulfidation deactivation degree is <5%, and the sulfur resistance is improved by more than 10 times compared to existing technologies.

[0026] (4) A significant improvement in mercury removal capacity. The mercury removal capacity of existing silver-loaded molecular sieves is only 0.36–0.40 mg / g. This invention improves the mercury removal capacity to 0.92 mg / g through an Ag-CuO bimetallic synergistic mechanism, in which Ag provides amalgamation and CuS provides additional mercury-loving sites, which is more than 130% higher than the existing technology.

[0027] (5) Simplification of preparation process and potential for large-scale production. This invention uses the sol-gel method to grow SiO2 nanoneedles, which only requires conventional wet reaction equipment. The process is simple and low-cost, and has clear prospects for large-scale production and industrial application.

[0028] (6) The present invention adopts a preparation strategy of first constructing a biomimetic superhydrophobic surface and then confining and loading Ag-CuO, which ensures the hydrophobic and oleophobic properties of the surface while achieving uniform loading and protection of active components in the mesoporous channels. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings: Figure 1 SEM image of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent prepared in Example 1 of the present invention.

[0030] Figure 2-4 Low-magnification and high-magnification TEM images and EDS elemental distribution maps of SBA-15 prepared in Example 1 of this invention under Ag-CuO bimetallic confinement loading.

[0031] Figure 5 A bar chart comparing the mercury removal capacity of each embodiment and the comparative example of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent prepared according to the present invention. Detailed Implementation

[0032] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0033] All the raw materials required for this invention can be purchased through commercial channels.

[0034] The "superhydrophobic surface" mentioned in this invention is a hydrophobic and oleophobic surface.

[0035] The evaluation method for the removal of mercury from natural gas by the mercury removal agent of this invention is as follows: Detection method: The concentration of trace mercury in natural gas was determined using a fixed-bed dynamic adsorption method and a cold atom fluorescence mercury analyzer.

[0036] The experimental conditions used a fixed-bed adsorption device with an inner diameter of 10 mm and a mercury removal agent loading of 5 g. The feed gas composition was CH4 95%, C2H6 3%, and C3H8 2%; the mercury concentration was 50 μg / m³; the operating pressure was 10 MPa; the operating temperature was 30 °C; the empty column gas velocity was 2.0 m / min; and the space velocity was 4000-6000 h⁻¹. - ¹. Humidity conditions: the feed gas was bubbled through a bubbler to achieve a relative humidity of 100%, and 0.5 wt% condensate oil (n-dodecane:toluene = 4:1) was added. Regeneration temperature was 300-350℃; regeneration atmosphere was air; gas flow rate was 100 mL / min; regeneration time was 4 hours; and regeneration cycles were 10 times. Water contact angle was measured using deionized water with a droplet volume of 5 μL at room temperature; oil contact angle was measured using n-hexadecane with a droplet volume of 5 μL at room temperature; mesoporous structure was characterized using N₂ adsorption-desorption.

[0037] The main technical concept of this invention is as follows: a step-by-step strategy of "temporary pore filling protection - biomimetic construction of the outer surface - pore filling agent removal - metal loading and fluorine replenishment" is adopted. The mesoporous channels are temporarily protected by the pore filling agent. SiO2 nanoneedle arrays are grown on the outer surface of SBA-15 and combined with fluorination modification to construct a super-bihydrophobic structure similar to that of a snapdragon. After removing the pore filling agent, Ag-CuO is loaded in a confined space. Finally, the fluorinated layer is repaired by replenishing fluorine, thereby realizing the functional partitioning of super-bihydrophobic surface and high activity in the pores.

[0038] Specifically, this invention employs a temporary pore-filling protection strategy to address the mesopore blockage problem during the construction of the biomimetic coating. A SiO2 nanoneedle array is grown on the outer surface of SBA-15 using a sol-gel method to simulate the micro-nano rough structure of springtail epidermis. This is combined with fluorination modification via vapor-phase FAS deposition to achieve a superhydrophobic surface, blocking water and condensate oil contamination at the source. After removing the pore-filling agent, Ag and CuO are confined and loaded within the hydrophilic mesoporous channels, forming a functional partition between a hydrophobic surface and a hydrophilic interior: Ag forms an amalgam with mercury to achieve chemisorption and mercury removal; CuO preferentially reacts with H2S to generate CuS, protecting Ag from sulfide poisoning. Simultaneously, CuS provides additional mercury-affinity sites, synergistically enhancing the mercury removal capacity with Ag. To address the thermal decomposition of the fluorinated layer during the heat treatment of the pore-filling agent removal process, secondary fluorination is performed after metal loading to achieve complete repair of the hydrophobic layer. As a whole, the technical solution of this invention achieves a breakthrough technical effect with a mercury removal capacity of 0.92 mg / g, a moisture efficiency of >94%, and a retention rate of >95% after 10 cycles under sulfur-containing humid conditions.

[0039] The present invention will be further described below with reference to specific embodiments.

[0040] Example 1: A method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury-removing agent with a structure similar to the skin of a snapdragon, specifically including the following steps: Step 1: Weigh 2.0g of commercial SBA-15 mesoporous molecular sieve (pore size 7-8 nm, specific surface area 750 m² / g), disperse it in 50 mL of ethanol, add 2.0g of PEG 4000, stir and dissolve at 50℃, then evaporate the ethanol at 60℃ to obtain SBA-15 with pore-filled protection.

[0041] Step 2, SiO2 nanoneedle growth: The SBA-15 obtained in Step 1, after pore filling and protection, was dispersed in 200 mL of a mixed solution (pH≈10) containing 0.025 M TEOS and 0.5 M ammonia. The mixture was stirred at 50 °C for 12 hours. After filtration, washing with ethanol, and drying at 80 °C, an array of SiO2 nanoneedles was formed on the outer surface of the material. The needles were 100-150 nm long, 15-20 nm in diameter, and spaced 30-50 nm apart.

[0042] Step 3: Place the product obtained in Step 2 into a CVD reactor, add 10% (by product mass) of perfluorodecyltrichlorosilane (FDTS), evacuate to 5 Pa, heat to 100°C, and maintain the reaction temperature for 4 hours. After removal, vacuum dry at 120°C for 2 hours to obtain SBA-15 with a superhydrophobic surface.

[0043] Step 4: Place the material obtained in Step 3 in a muffle furnace and heat-treat it at 350°C for 3 hours in an air atmosphere with a heating rate of 2°C / min to remove the PEG filling agent that fills the mesoporous channels and open the mesoporous channels.

[0044] Step 5, Ag-CuO confined loading: Prepare an equal volume mixed solution of 0.5 M AgNO3 and 0.75 M Cu(NO3)2 (Ag:Cu = 1:1.5). Add 1.0 mL of the mixed solution dropwise to 1.0 g of the material obtained in Step 4, ultrasonically disperse for 15 minutes, allow to stand for 12 hours, dry at 100℃, and calcine at 400℃ in air atmosphere for 3 hours (heating rate 2℃ / min) to obtain the Ag-CuO@SBA-15 composite. The CuO loading is 5 wt%, and the Ag loading is 5 wt%. Figure 2-4 As shown, TEM and EDS characterization confirmed that Ag and CuO nanoparticles were successfully confined and loaded inside the mesoporous channels of SBA-15. The particle diameter was about 5-10 nm, and they were uniformly distributed in the channels without obvious aggregation on the outer surface.

[0045] Step 6, Fluorine Replenishment and Repair: Place the material obtained in Step 5 back into the CVD reactor, add 5% FDTS by mass of the material, evacuate to 5 Pa, heat to 100℃, and maintain the temperature for 2 hours to repair the fluorinated layer decomposed in Step 4, and obtain the final mercury removal agent, denoted as Ag-CuO@SBA-15-SP.

[0046] The hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent prepared in this embodiment was tested using simulated natural gas as the feed gas. The results showed that the water contact angle was 156.2° and the oil contact angle was 147.5°, achieving excellent superhydrophobic and oleophobic properties. Regarding mercury removal performance, the removal capacity was 0.92 mg / g under dry gas conditions and 0.87 mg / g under wet gas conditions, with a wet / dry gas efficiency as high as 94.6%. In terms of sulfur resistance, after continuous operation for 50 hours in wet gas containing 80 ppm H2S, the mercury removal capacity retention rate was 91%, and XPS analysis showed that the Ag sulfurization deactivation degree was less than 5%. Regarding regeneration performance, after 10 adsorption-regeneration cycles, the mercury removal capacity retention rate was 96.8%, the water contact angle retention rate was 97.5%, and the regeneration temperature could be controlled within 330-350℃. These results indicate that this mercury removal agent possesses excellent superhydrophobic and oleophobic properties, high mercury removal capacity, good resistance to sulfur poisoning, and excellent regenerable stability.

[0047] Figure 1 SEM image of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent prepared in Example 1 of the present invention. Figures 2-4 Low-magnification and high-magnification TEM images and EDS elemental distribution maps of SBA-15 prepared in Example 1 of this invention under Ag-CuO bimetallic confinement loading.

[0048] Example 2: A method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury-removing agent with a structure similar to the skin of a snapdragon, specifically including the following steps: Step 1: Weigh 2.0g of commercial SBA-15 mesoporous molecular sieve (pore size 7-8 nm, specific surface area 750 m² / g), disperse it in 50 mL of ethanol, add 1.0g of PEG 4000 (pore-filling agent to carrier mass ratio 0.5:1), stir to dissolve at 50℃, and then evaporate the ethanol at 60℃ to obtain pore-filled and protected SBA-15.

[0049] Step 2, SiO2 nanoneedle growth: The SBA-15 obtained in Step 1, after pore filling and protection, was dispersed in 200 mL of a mixed solution (pH≈10) containing 0.025 M TEOS and 0.5 M ammonia. The mixture was stirred at 50 °C for 6 hours. After filtration, washing with ethanol, and drying at 80 °C, an array of SiO2 nanoneedles was formed on the outer surface of the material. The needles were 50-80 nm long, 15-20 nm in diameter, and spaced 30-50 nm apart.

[0050] Step 3: Place the product obtained in Step 2 into a CVD reactor, add 10% (by mass) of perfluorodecyltrichlorosilane (FDTS), evacuate to 5 Pa, heat to 100°C, and maintain the reaction temperature for 4 hours. After removal, vacuum dry at 120°C for 2 hours to obtain SBA-15 with a superhydrophobic surface.

[0051] Step 4: Place the material obtained in Step 3 in a muffle furnace and heat-treat it at 350°C for 3 hours in an air atmosphere with a heating rate of 2°C / min to remove the PEG filling agent that fills the mesoporous channels and open the mesoporous channels.

[0052] Step 5, Ag-CuO confined loading: Prepare a mixed solution of equal volumes of 0.3 M AgNO3 and 0.3 M Cu(NO3)2 (Ag:Cu=1:1, the total metal salt concentration is reduced to about 50% of that in Example 1), and obtain a mercury removal agent after calcination, wherein the CuO loading is about 2.5 wt%, the Ag loading is about 2.5 wt%, and the total compound loading is about 5 wt%.

[0053] Step 5: Ag-CuO confined loading: Prepare an equal volume mixed solution of 0.3 M AgNO3 and 0.45 M Cu(NO3)2 (Ag:Cu = 1:1.5). Add 1.0 mL of the mixed solution dropwise to 1.0 g of the material obtained in Step 4, sonicate for 15 minutes, allow to stand for 12 hours, dry at 100℃, and calcine at 400℃ in air for 3 hours (heating rate 2℃ / min) to obtain the Ag-CuO@SBA-15 composite. The CuO loading is approximately 2.5 wt%, the Ag loading is approximately 2.5 wt%, and the total compound loading is approximately 5 wt%.

[0054] Step 6, Fluorine Replenishment and Repair: Place the material obtained in Step 5 back into the CVD reactor, add 5% FDTS by mass of the material, evacuate to 5 Pa, heat to 100℃, and maintain the temperature for 2 hours to repair the fluorinated layer decomposed in Step 4, and obtain the final mercury removal agent, denoted as Ag-CuO@SBA-15-SP.

[0055] The mercury removal material prepared in this embodiment was tested using the same methods as in Example 1. The results showed: a water contact angle of 152.8° and an oil contact angle of 141.5°; a mesoporous pore volume retention rate of 94%; a mercury removal capacity of 0.85 mg / g under dry gas conditions and 0.79 mg / g under humid conditions, with a humid / dry gas efficiency of 93.5%; regarding sulfur resistance, after 50 hours of continuous operation in humid gas containing 80 ppm H2S, the mercury removal capacity retention rate was 86%, and XPS analysis showed an Ag sulfidation deactivation rate of approximately 7.5%; after 10 adsorption-regeneration cycles, the mercury removal capacity retention rate was 96.2%, and the water contact angle retention rate was 95.8%.

[0056] Example 3: A method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury-removing agent with a structure similar to the skin of a snapdragon, specifically including the following steps: Step 1: Weigh 2.0g of commercial SBA-15 mesoporous molecular sieve (pore size 7-8 nm, specific surface area 750 m² / g), disperse it in 50 mL of ethanol, add 3.0g of PEG 4000 (pore-filling agent to carrier mass ratio 1.5:1), stir to dissolve at 50℃, and then evaporate the ethanol at 60℃ to obtain pore-filled and protected SBA-15.

[0057] Step 2, SiO2 nanoneedle growth: The SBA-15 obtained in Step 1, after pore filling and protection, was dispersed in 200 mL of a mixed solution (pH≈10) containing 0.025 M TEOS and 0.5 M ammonia. The mixture was stirred at 50 °C for 12 hours. After filtration, washing with ethanol, and drying at 80 °C, an array of SiO2 nanoneedles was formed on the outer surface of the material. The needles were 100-150 nm long, 15-20 nm in diameter, and spaced 30-50 nm apart.

[0058] Step 3: Place the product obtained in Step 2 into a CVD reactor, add 10% (by mass) of perfluorodecyltrichlorosilane (FDTS), evacuate to 5 Pa, heat to 100°C, and maintain the reaction temperature for 4 hours. After removal, vacuum dry at 120°C for 2 hours to obtain SBA-15 with a superhydrophobic surface.

[0059] Step 4: Place the material obtained in Step 3 in a muffle furnace and heat-treat it at 350°C for 3 hours in an air atmosphere with a heating rate of 2°C / min to remove the PEG filling agent that fills the mesoporous channels and open the mesoporous channels.

[0060] Step 5: Ag-CuO confined loading: Prepare an equal volume mixed solution of 0.8 M AgNO3 and 1.2 M Cu(NO3)2 (Ag:Cu = 1:1.5). Add 1.0 mL of the mixed solution dropwise to 1.0 g of the material obtained in Step 4, ultrasonically disperse for 15 minutes, allow to stand for 12 hours, dry at 100℃, and calcine in air at 400℃ for 3 hours to obtain the Ag-CuO@SBA-15 composite. ICP-OES analysis showed that the Ag loading was 8.5 wt%, the CuO loading was 9.5 wt%, and the total metal loading (Ag+Cu) was approximately 16 wt%.

[0061] Step 6, Fluorine Replenishment and Repair: Place the material obtained in Step 5 back into the CVD reactor, add 5% FDTS by mass of the material, evacuate to 5 Pa, heat to 100℃, and maintain the temperature for 2 hours to repair the fluorinated layer decomposed in Step 4, and obtain the final mercury removal agent, denoted as Ag-CuO@SBA-15-SP.

[0062] The mercury removal material prepared in this embodiment was tested using the same methods as in Example 1. The results showed: a water contact angle of 158.3° and an oil contact angle of 149.2°; a mesoporous pore volume retention rate of 89%; a mercury removal capacity of 0.94 mg / g under dry gas conditions and 0.88 mg / g under humid conditions, with a humid / dry gas efficiency of 93.8%; regarding sulfur resistance, after continuous operation for 50 hours in humid gas containing 80 ppm H2S, the mercury removal capacity retention rate was 93%, and XPS analysis showed that the Ag sulfurization deactivation degree was less than 4%; after 10 adsorption-regeneration cycles, the mercury removal capacity retention rate was 96.5%, and the water contact angle retention rate was 96.1%.

[0063] Example 4: A method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury-removing agent with a structure similar to the skin of a snapdragon, specifically including the following steps: Step 1: Weigh 2.0g of commercial SBA-15 mesoporous molecular sieve (pore size 7-8 nm, specific surface area 750 m² / g), disperse it in 50 mL of ethanol, add 2.0g of paraffin (melting point 50-60℃), stir to dissolve at 50℃, and then evaporate the ethanol at 60℃ to obtain SBA-15 with pore-filled protection.

[0064] Step 2, SiO2 nanoneedle growth: The SBA-15 obtained in Step 1, after pore filling and protection, was dispersed in 200 mL of a mixed solution (pH≈10) containing 0.025 M TEOS and 0.5 M ammonia. The mixture was stirred at 50 °C for 12 hours. After filtration, washing with ethanol, and drying at 80 °C, an array of SiO2 nanoneedles was formed on the outer surface of the material. The needles were 100-150 nm long, 15-20 nm in diameter, and spaced 30-50 nm apart.

[0065] Step 3: Place the product obtained in Step 2 into a CVD reactor, add 10% (by weight) of tridecafluorooctyltriethoxysilane, evacuate to 5 Pa, heat to 100°C, and maintain the reaction temperature for 4 hours. After removal, vacuum dry at 120°C for 2 hours to obtain SBA-15 with a superhydrophobic surface.

[0066] Step 4: Place the material obtained in Step 3 in a muffle furnace and heat-treat it at 380°C for 2 hours in an air atmosphere at a heating rate of 2°C / min to remove the paraffin filling agent that fills the mesoporous channels and open the mesoporous channels.

[0067] Step 5: Ag-CuO confined loading: Prepare a mixed solution of equal volumes of 0.5 M AgNO3 and 0.75 M Cu(NO3)2 (Ag:Cu = 1:1.5). Add 5 mL of this mixed solution dropwise to 1.0 g of the material obtained in Step 4, ultrasonically disperse for 15 minutes, allow to stand for 12 hours, dry at 100℃, and calcine in air at 400℃ for 3 hours (heating rate 2℃ / min) to obtain the Ag-CuO@SBA-15 composite. The CuO loading is 5 wt%, and the Ag loading is 5 wt%.

[0068] Step 6, Fluorine Replenishment and Repair: Place the material obtained in Step 5 back into the CVD reactor, add 5% of the material mass of tridecafluorooctyltriethoxysilane, evacuate to 5 Pa, heat to 100℃, and maintain the temperature for 2 hours to repair the fluorinated layer decomposed in Step 4, thus obtaining the final mercury removal agent.

[0069] The mercury removal material prepared in this embodiment was tested using the same methods as in Example 1. The results showed: a water contact angle of 154.8° and an oil contact angle of 144.3°; mesoporous pore volume retention of 91%. Regarding mercury removal performance, the removal capacity was 0.90 mg / g under dry gas conditions and 0.85 mg / g under wet gas conditions, with a wet / dry gas efficiency of 94.0%. In terms of sulfur resistance, after 50 hours of continuous operation in wet gas containing 80 ppm H2S, the mercury removal capacity retention rate was 90%, and XPS analysis showed an Ag sulfurization deactivation degree of approximately 5.5%. Regarding regeneration performance, after 10 adsorption-regeneration cycles, the mercury removal capacity retention rate was 96.0%, and the water contact angle retention rate was 95.5%.

[0070] Comparative Example 1: The difference from Example 1 is that: no temporary hole-filling protection is performed, and the original SBA-15 is processed directly.

[0071] A method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury-removing agent with a structure similar to the skin of a snapdragon includes the following steps: Step 1: SiO2 Nanoneedle Growth: 2.0 g of commercial SBA-15 mesoporous molecular sieve was dispersed in 200 mL of a mixed solution (pH≈10) containing 0.025 MTEOS and 0.5 M ammonia water, and the mixture was stirred at 50 °C for 12 hours. After filtration, washing with ethanol, and drying at 80 °C, an array of SiO2 nanoneedles was formed on the outer surface of the material. The needles were 100-150 nm long, 15-20 nm in diameter, and spaced 30-50 nm apart.

[0072] Step 2: Place the product obtained in Step 1 into a CVD reactor, add 10% (by product mass) of perfluorodecyltrichlorosilane (FDTS), evacuate to 5 Pa, heat to 100°C, and maintain the reaction temperature for 4 hours. After removal, vacuum dry at 120°C for 2 hours to obtain SBA-15 with a superhydrophobic surface.

[0073] Step 3: Ag-CuO confined loading: Prepare a mixed solution of equal volumes of 0.5 M AgNO3 and 0.75 M Cu(NO3)2 (Ag:Cu = 1:1.5). Add 1.0 mL of the mixed solution dropwise to 1.0 g of the material obtained in Step 2, ultrasonically disperse for 15 minutes, allow to stand for 12 hours, dry at 100℃, and calcine in air at 400℃ for 3 hours (heating rate 2℃ / min) to obtain the Ag-CuO@SBA-15 composite. The CuO loading is 5 wt%, and the Ag loading is 5 wt%.

[0074] Step 4, Fluorine Replenishment and Repair: Place the material obtained in Step 3 back into the CVD reactor, add 5% FDTS by mass of the material, evacuate to 5 Pa, heat to 100℃, and maintain the temperature for 2 hours to repair the fluorinated layer that may have decomposed during the metal-supported calcination process after fluorination in Step 2, and obtain the final mercury removal agent.

[0075] The results showed a water contact angle of 148.5° and an oil contact angle of 138.2°. N2 adsorption-desorption characterization revealed a mesopore volume retention rate of only 28%, and the BET specific surface area decreased from the original 750 m² / g to 210 m² / g, indicating severe blockage caused by the SiO2 nanoneedle growth solution entering the pores. Regarding mercury removal performance, the removal capacity was 0.58 mg / g under dry gas conditions and 0.47 mg / g under humid gas conditions, with a humid / dry gas efficiency of 81.2%. In terms of sulfur resistance, after 50 hours of continuous operation in humid gas containing 80 ppm H2S, the mercury removal capacity retention rate was 72%, and XPS analysis showed an Ag sulfurization deactivation degree of approximately 18%. Regarding regeneration performance, after 10 adsorption-regeneration cycles, the mercury removal capacity retention rate was 85.2%, and the water contact angle retention rate was 86.5%. This indicates that without pore-filling protection, SiO2 nanoneedles block the mesopore channels, leading to Hg... 0 It cannot effectively enter the pores and contact the active sites.

[0076] Comparative Example 2: The difference from Example 1 is that the metal is loaded first, and then the biomimetic structure is constructed.

[0077] Step 1: Ag-CuO confined loading: Prepare an equal-volume mixed solution of 0.5 M AgNO3 and 0.75 M Cu(NO3)2 (Ag:Cu = 1:1.5). Add 1.0 mL of this mixed solution dropwise to 1.0 g of commercial SBA-15 mesoporous molecular sieve, sonicate for 15 minutes, allow to stand for 12 hours, dry at 100℃, and calcine at 400℃ in air for 3 hours (heating rate 2℃ / min) to obtain the Ag-CuO@SBA-15 composite. The CuO loading is 5 wt%, and the Ag loading is 5 wt%.

[0078] Step 2: Weigh the product from Step 1, disperse it in 50 mL of ethanol, add 2.0 g of PEG 4000, stir and dissolve at 50 °C, then evaporate the ethanol at 60 °C to obtain SBA-15 after pore filling and protection.

[0079] Step 3: SiO2 nanoneedle growth: The SBA-15 obtained in Step 2, after pore filling and protection, was dispersed in 200 mL of a mixed solution (pH≈10) containing 0.025 M TEOS and 0.5 M ammonia. The mixture was stirred at 50 °C for 12 hours. After filtration, washing with ethanol, and drying at 80 °C, an array of SiO2 nanoneedles was formed on the outer surface of the material. The needles were 100-150 nm long, 15-20 nm in diameter, and spaced 30-50 nm apart.

[0080] Step 4: Place the product obtained in Step 3 into a CVD reactor, add 10% (by mass) of perfluorodecyltrichlorosilane (FDTS), evacuate to 5 Pa, heat to 100°C, and maintain the reaction temperature for 4 hours. After removal, vacuum dry at 120°C for 2 hours to obtain SBA-15 with a superhydrophobic surface.

[0081] Step 5: Place the material obtained in Step 4 in a muffle furnace and heat-treat it at 350°C for 3 hours in an air atmosphere with a heating rate of 2°C / min to remove the PEG pore filler filling the mesoporous channels and open the mesoporous channels.

[0082] Step 6, Fluorine Replenishment and Repair: Place the material obtained in Step 5 back into the CVD reactor, add 5% FDTS by mass of the material, evacuate to 5 Pa, heat to 100℃, and maintain the temperature for 2 hours to repair the fluorinated layer decomposed in Step 4, thus obtaining the final mercury removal agent.

[0083] The results showed a water contact angle of 138.5° and an oil contact angle of 108.6°. N2 adsorption-desorption characterization indicated a mesoporous pore volume retention of 88% (acceptable, as pore-filling protection remains). XPS surface analysis showed significant enrichment of Ag and CuO signals on the outer surface, indicating that the active metal components migrated to the outer surface during subsequent biomimetic construction. Regarding mercury removal performance, the removal capacity was 0.71 mg / g under dry gas conditions and 0.61 mg / g under humid gas conditions, with a humid / dry gas efficiency of 85.6%. In terms of sulfur resistance, after 50 hours of continuous operation in humid gas containing 80 ppm H2S, the mercury removal capacity retention rate was 78%, and XPS analysis showed approximately 12% Ag deactivation due to sulfurization. Regarding regeneration performance, after 10 adsorption-regeneration cycles, the mercury removal capacity retention rate was 82.5%, and the water contact angle retention rate was 84.2%. These results indicate that subsequent biomimetic construction disrupts the distribution of the loaded active components and reduces hydrophobic and oleophobic properties.

[0084] Comparative Example 3: The difference from Example 1 is that no SiO2 nanoneedles were grown.

[0085] Step 1: Weigh 2.0g of commercial SBA-15 mesoporous molecular sieve (pore size 7-8 nm, specific surface area 750 m² / g), disperse it in 50 mL of ethanol, add 2.0g of PEG 4000, stir and dissolve at 50℃, then evaporate the ethanol at 60℃ to obtain SBA-15 with pore-filled protection.

[0086] Step 2: Place the product obtained in Step 1 into a CVD reactor, add 10% (by mass) of perfluorodecyltrichlorosilane (FDTS), evacuate to 5 Pa, heat to 100°C, and maintain the temperature for 4 hours. After removal, vacuum dry at 120°C for 2 hours to obtain SBA-15 with a superhydrophobic surface.

[0087] Step 3: Place the material obtained in Step 2 in a muffle furnace and heat-treat it at 350°C for 3 hours in an air atmosphere with a heating rate of 2°C / min to remove the PEG filling agent that fills the mesoporous channels and open the mesoporous channels.

[0088] Step 4: Ag-CuO confined loading: Prepare an equal volume mixed solution of 0.5 M AgNO3 and 0.75 M Cu(NO3)2 (Ag:Cu = 1:1.5). Add 1.0 mL of the mixed solution dropwise to 1.0 g of the material obtained in Step 3, ultrasonically disperse for 15 minutes, allow to stand for 12 hours, dry at 100℃, and calcine at 400℃ in air for 3 hours (heating rate 2℃ / min) to obtain the Ag-CuO@SBA-15 composite. The CuO loading is 5 wt%, and the Ag loading is 5 wt%.

[0089] Step 5, Fluorine Replenishment and Repair: Place the material obtained in Step 4 back into the CVD reactor, add 5% FDTS by mass of the material, evacuate to 5 Pa, heat to 100℃, and maintain the temperature for 2 hours to repair the fluorinated layer decomposed in Step 3, thus obtaining the final mercury removal agent.

[0090] The results showed a water contact angle of 118.6° and an oil contact angle of 71.3°. N2 adsorption-desorption characterization indicated a mesoporous pore volume retention rate of 93% (effective pore-filling protection and good pore opening). Regarding mercury removal performance, the removal capacity was 0.65 mg / g under dry gas conditions and 0.51 mg / g under wet gas conditions, with a wet / dry gas efficiency of 78.5%. In terms of sulfur resistance, after 50 hours of continuous operation in wet gas containing 80 ppm H2S, the mercury removal capacity retention rate was 83%, and XPS analysis showed an Ag sulfurization deactivation degree of approximately 9%. Regarding regeneration performance, after 10 adsorption-regeneration cycles, the mercury removal capacity retention rate was 88.6%, and the water contact angle retention rate was 82.3%. These results indicate that without the nanoneedle structure, the superhydrophobic properties significantly decreased with only fluorination modification, failing to effectively repel water and oil.

[0091] Comparative Example 4: The difference from Example 1 is that no fluoride supplementation was used for the repair.

[0092] Step 1: Weigh 2.0g of commercial SBA-15 mesoporous molecular sieve (pore size 7-8 nm, specific surface area 750 m² / g), disperse it in 50 mL of ethanol, add 2.0g of PEG 4000, stir and dissolve at 50℃, then evaporate the ethanol at 60℃ to obtain SBA-15 with pore-filled protection.

[0093] Step 2, SiO2 nanoneedle growth: The SBA-15 obtained in Step 1, after pore filling and protection, was dispersed in 200 mL of a mixed solution (pH≈10) containing 0.025 M TEOS and 0.5 M ammonia. The mixture was stirred at 50 °C for 12 hours. After filtration, washing with ethanol, and drying at 80 °C, an array of SiO2 nanoneedles was formed on the outer surface of the material. The needles were 100-150 nm long, 15-20 nm in diameter, and spaced 30-50 nm apart.

[0094] Step 3: Place the product obtained in Step 2 into a CVD reactor, add 10% (by mass) of perfluorodecyltrichlorosilane (FDTS), evacuate to 5 Pa, heat to 100°C, and maintain the reaction temperature for 4 hours. After removal, vacuum dry at 120°C for 2 hours to obtain SBA-15 with a superhydrophobic surface.

[0095] Step 4: Place the material obtained in Step 3 in a muffle furnace and heat-treat it at 350°C for 3 hours in an air atmosphere with a heating rate of 2°C / min to remove the PEG filling agent that fills the mesoporous channels and open the mesoporous channels.

[0096] Step 5: Ag-CuO confined loading: Prepare an equal volume mixed solution of 0.5 M AgNO3 and 0.75 M Cu(NO3)2 (Ag:Cu = 1:1.5). Add 1.0 mL of the mixed solution dropwise to 1.0 g of the material obtained in Step 4, ultrasonically disperse for 15 minutes, allow to stand for 12 hours, dry at 100℃, and calcine at 400℃ in air for 3 hours (heating rate 2℃ / min) to obtain the Ag-CuO@SBA-15 composite. The CuO loading is 5 wt%, and the Ag loading is 5 wt%.

[0097] The results showed a water contact angle of 128.3° and an oil contact angle of 95.6°. N2 adsorption-desorption characterization indicated a mesoporous pore volume retention rate of 91% (good pore opening). Regarding mercury removal performance, the mercury removal capacity was 0.72 mg / g under dry gas conditions and 0.61 mg / g under wet gas conditions, with a wet / dry gas efficiency of 84.2%. In terms of sulfur resistance, after 50 hours of continuous operation in wet gas containing 80 ppm H2S, the mercury removal capacity retention rate was 85%, and XPS analysis showed an Ag sulfurization deactivation degree of approximately 8%. Regarding regeneration performance, after 10 adsorption-regeneration cycles, the mercury removal capacity retention rate decreased to 78.5%, and the water contact angle retention rate decreased to 75.6%. This indicates that the heat treatment during the removal of the pore filler led to the decomposition of the fluorinated layer, and without fluorine replenishment for repair, the superhydrophobic and dihydrophobic properties decreased, resulting in insufficient long-term stability.

[0098] The mercury removal capacity comparison bar chart of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent prepared in Examples 1-4 of this invention and the mercury removal agent prepared in Comparative Examples 1-4 is shown below. Figure 5 As shown.

[0099] Any parts not mentioned in this invention can be achieved by referring to existing technologies.

[0100] Those skilled in the art should recognize that the above embodiments are merely illustrative of this application and are not intended to limit this application. Any appropriate changes and variations made to the above embodiments within the essential spirit and scope of this application fall within the scope of protection of the claims of this application.

Claims

1. A method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury-removing agent with a shell-like structure, characterized in that, The steps are as follows: a. Temporary pore-filling protection: Disperse SBA-15 mesoporous molecular sieve in an organic solvent, add a polymeric pore-filling agent, stir thoroughly, and then evaporate the organic solvent to allow the polymeric pore-filling agent to fill the mesoporous channels of SBA-15. b. Biomimetic superhydrophobic modification of the outer surface: The SBA-15 obtained after temporary pore filling protection in step a is placed in an alkaline reaction solution containing silicon precursor, and SiO2 nanoneedle arrays are grown on its outer surface by sol-gel method to construct a micro-nano composite structure inspired by the snaptail worm; then the obtained product is placed in a chemical vapor deposition reactor, and fluorination modification is performed by chemical vapor deposition using fluoroalkylsilane as a precursor to obtain SBA-15 with a superhydrophobic surface; c. Removal of polymeric pore filler: The SBA-15 with superhydrophobic surface obtained in step b is heat-treated to remove the polymeric pore filler, thereby opening the mesoporous channels; the heat treatment also causes some of the fluorinated layer to decompose. d. Ag-CuO confined loading and fluoride remediation: The product obtained in step c was impregnated in a mixed solution containing copper salt and silver precursor, and Cu² was added using an equal-volume impregnation method. + and Ag + The Ag-CuO@SBA-15 composite was introduced into the mesoporous channels of SBA-15, dried, and calcined to obtain the composite. The obtained material was then placed in a vapor deposition reactor for secondary vapor-phase fluorination deposition to repair the fluorinated layer decomposed in step c and restore the superhydrophobic properties of the material's outer surface.

2. The preparation method of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure resembling that of a snapdragon, as described in claim 1, is characterized in that: In step a, the polymeric pore-filling agent is one or more of polyethylene glycol, polyvinyl alcohol, or paraffin with a molecular weight of 2000 to 20000, and the mass ratio of the polymeric pore-filling agent to the SBA-15 mesoporous molecular sieve is 0.5 to 2:1; the organic solvent is ethanol or acetone.

3. The preparation method of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure resembling that of a snapdragon, as described in claim 2, is characterized in that: In step a, the mixture is stirred at a temperature of 45–55°C and the organic solvent is evaporated by rotary evaporation at a temperature of 55–65°C.

4. The preparation method of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure resembling that of a snapdragon, as described in claim 1, is characterized in that: In step b, the silicon-containing precursor is tetraethoxysilane or tetramethoxysilane; the specific steps for growing the SiO2 nanoneedle array on its outer surface by the sol-gel method are as follows: the SBA-15 obtained after temporary pore filling protection in step a is placed in an ammonia reaction solution of the silicon-containing precursor, the concentration of the silicon-containing precursor is 0.01-0.05 M, the pH of the reaction solution is adjusted to 8-10 with ammonia, the temperature is 40-60℃, and the reaction is carried out for 6-24 hours; after filtration, washing and drying, the SiO2 nanoneedle array is obtained.

5. The preparation method of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure resembling that of a snapdragon, as described in claim 4, is characterized in that: The reaction conditions of the vapor deposition reactor are: temperature 80-120℃, vacuum degree <10 Pa, and deposition time 2-6 hours; the fluoroalkylsilane is perfluorodecyltrichlorosilane, perfluorodecyltriethoxysilane or tridecafluorooctyltriethoxysilane.

6. The method for preparing a hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury-removing agent with a shell-like structure resembling a snapdragon's skin, as described in claim 1, is characterized in that: In step c, the conditions for heat treatment to remove the polymer pore filler are: heat treatment at 300-400℃ for 2-4 hours in air atmosphere.

7. The preparation method of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure resembling that of a snapdragon, as described in claim 1, is characterized in that: In step d, the copper salt is copper nitrate, and the silver precursor is silver ammonia solution or silver nitrate; the calcination temperature is 300-500℃, and the calcination time is 2-4 hours; the secondary vapor phase fluorination deposition conditions are: temperature 80-120℃, vacuum degree <10 Pa, time 1-3 hours, and the amount of fluoroalkylsilane used is 3-8% of the mass of Ag-CuO@SBA-15 composite.

8. A hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent mimicking the skin structure of a springtail beetle, characterized in that... It is prepared by the preparation method according to any one of claims 1 to 7, comprising an SBA-15 mesoporous molecular sieve and a slug-like micro / nanostructure located on the outer surface of the SBA-15 mesoporous molecular sieve. The slug-like micro / nanostructure is constructed by an array of SiO2 nanoneedles, the length of which is 50–200 nm, the diameter of which is 10–30 nm, and the spacing between adjacent nanoneedles is 30–80 nm. The surface of the slug-like micro / nanostructure is chemically bonded and modified with a fluoroalkylsilane hydrophobic and oleophobic layer. Silver nanoparticles and copper oxide are confined and loaded inside the mesoporous channels of the SBA-15 mesoporous molecular sieve. The loading amount of copper oxide is 1–10 wt% of the total mass of the mercury removal agent. The loading amount of silver nanoparticles is 1–10 wt% of the total mass of the mercury removal agent.

9. The application of the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent with a shell-like structure as described in claim 8 in the wet mercury removal of natural gas.

10. The application according to claim 9, characterized in that: The application includes: filling the hydrophobic and oleophobic silver-loaded copper oxide SBA-15 mercury removal agent into a fixed-bed adsorption tower to treat mercury-containing natural gas moisture. After adsorption saturation, it is oxidized and regenerated in an oxygen-containing atmosphere at 300-400℃, while gasified fluoroalkylsilane is introduced for in-situ fluorine replenishment and remediation.

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