A method for preparing a hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent by a microdroplet template method and application thereof

Abstract

The application discloses a method for preparing a hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent by using a microdroplet template method and application thereof. Thiophene is dissolved in a n-heptane solution to form a non-polar mixed solution as a template agent. Then, aluminum isopropoxide, lanthanum nitrate hexahydrate is dissolved in deionized water and acetone, and methyl triethoxysilane is added to form a polar mixed solution. Finally, the non-polar template agent solution is added, and the mixture is fully stirred under acidic conditions to obtain a hydrophobic La-Al / SiO2 sol containing a microdroplet template. The hydrophobic La-Al / SiO2 composite aerogel adsorbent is obtained by aging, washing replacement and drying. The hydrophobic La-Al / SiO2 composite aerogel adsorbent has good pore regularity, surface hydrophobicity and multiple adsorption active centers, and has high adsorption selectivity and desulfurization performance for thiophene compounds in simulated aromatic hydrocarbons containing water and polar compounds.

Description

Technical Field

[0001] This invention belongs to the field of materials preparation and processing technology, specifically relating to a method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent using a microdroplet template method and its application. Background Technology

[0002] Aromatics, as one of the basic raw materials in the petrochemical industry, are widely used in synthetic fibers, rubber, pesticides, and pharmaceuticals. Industrially, catalytic reforming and thermal cracking of petroleum hydrocarbons are the main methods for producing aromatics. However, in these processes, the presence of sulfides in crude oil (such as thiophene, benzothiophene, and dibenzothiophene) can be transferred to the aromatic products during subsequent processing. This generates harmful substances during the use of aromatics, causing damage to the environment and human health. It can also poison catalysts in subsequent aromatic processing steps, leading to catalyst deactivation and decreased selectivity. Therefore, aromatic desulfurization has become a research focus in petroleum processing.

[0003] Currently, hydrodesulfurization technology is the most widely used technology in the petrochemical industry. It primarily removes chain sulfides such as sulfides, thiols, and disulfides. However, it is less effective at removing aromatic heterocyclic sulfides such as thiophene and its derivatives, requiring more stringent conditions. Due to the stability of the conjugated system of thiophene cyclic sulfides, high temperature, high pressure, and hydrogen saturation are needed to disrupt their stable structure and remove sulfur atoms. This process consumes significant energy and operating costs. Therefore, alternative deep desulfurization technologies need to be developed. Adsorption desulfurization technology, with its advantages of mild operating conditions, low cost, and good selectivity, has become one of the most widely used desulfurization technologies.

[0004] The core of adsorption desulfurization technology is selecting a suitable adsorbent as a carrier. A good adsorbent carrier can selectively remove sulfides from fuels. Currently reported adsorbents include metal-organic frameworks (MOFs), activated carbon, zeolite molecular sieves, aerogels, and metal oxides. Among them, aerogels are nanoscale mesoporous materials formed by the aggregation of colloidal particles. They possess physical properties such as high porosity, high specific surface area, and three-dimensional network structure, and are widely used in the field of adsorption desulfurization.

[0005] In previous studies, Zhejiang University of Technology (Publication No. CN 106590728 A), (Publication No. CN105709685 A), and (Publication No. CN 108893138 A) have successfully used Zr doping... 4+ Ag + Co + Cu + Al 3+SiO2 composite aerogels prepared with metal ions exhibit good adsorption and desulfurization performance for thiophene sulfides in simulated fuel oil. However, due to their hydrophilic nature, they have poor resistance to polar impurities, which reduces their adsorption and desulfurization performance for thiophene compounds in simulated aromatic hydrocarbons containing water and polar compounds. Meanwhile, Zhejiang University of Technology (Publication Nos. CN 117619354A, CN 119236882A, and CN119236883A) has improved this performance by doping with Pd... 2+ APTES, La 3+ DA, Ti 4+ Hydrophobic SiO2 composite aerogels prepared with various materials exhibit good anti-polarity effects and show good desulfurization performance for thiophene compounds in simulated aromatic hydrocarbons containing water and polar compounds. However, the hydrophobic Pd(II) / SiO2@APTES composite aerogels and hydrophobic La / SiO2@DA composite aerogels prepared by patents CN 117619354A and CN 119236882A have complex preparation processes, and the incorporation of organic amines leads to a mismatch in hydrolysis-condensation rates, making agglomeration easy and destroying the aerogel's texture structure, resulting in a decrease in specific surface area, a wide pore size distribution, and an irregular pore structure, which is not conducive to the diffusion of sulfides. Patent CN 119236883A improves the desulfurization performance of aerogels by incorporating single metals, and the preparation process is simple, but the single metal provides few adsorption active centers and has a low adsorption capacity.

[0006] Therefore, the invention improves the texture and enhances the pore regularity of the hydrophobic hybrid aerogel prepared by the microdroplet template method; the incorporation of Al and La bimetals provides two adsorption active centers and reduces the preparation complexity, thereby enhancing both desulfurization performance and adsorption capacity. Summary of the Invention

[0007] In view of the problems existing in the prior art, the purpose of this invention is to provide a method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent using a microdroplet template method and its application. In this method, a certain amount of thiophene is dissolved in n-heptane to form a nonpolar template agent solution, which is then added to a polar mixed solution of an aluminum source (aluminum isopropoxide), a lanthanum source (lanthanum nitrate hexahydrate), and a silicon source (methyltriethoxysilane) using water and acetone as solvents. The two sources are immiscible. The nonpolar template agent solution is stirred at high speed in the polar solution to form uniformly distributed microdroplets. During the sol-gel process, the -CH3 group in methyltriethoxysilane, due to its hydrophobicity, can interact with the hydrophobic template microdroplets, causing these precursors to hydrolyze and condense tightly around the template microdroplets, thereby forming a SiO2 gel framework, while Al... 3+ The incorporation of [a substance] can form a Si-O-Al framework structure with silicon species, thereby improving framework stability. 3+The template agent is enriched on the surface of the SiO2 gel framework by forming direct S-La bonds with the thiophene S atoms in the template microdroplets. The template microdroplets are then removed during a subsequent solvent displacement process. After drying, channels similar in shape to the template microdroplets are left in the prepared hydrophobic La-Al / SiO2 alcohol gel framework network, improving the regularity of the aerogel channels. Furthermore, this preparation method is simple to operate and has low template preparation cost.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows: A method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent using a microdroplet template method, wherein the composite aerogel is prepared by a sol-gel combined atmospheric pressure drying method using the microdroplet template method; specifically including the following steps: 1) Preparation of microdroplet template solution: Thiophene compounds are dissolved in n-heptane to form a template solution; 2) Preparation of hydrophobic alcohol gel containing microdroplet templates: Aluminum isopropoxide is dissolved in acetone; lanthanum nitrate hexahydrate is dissolved in deionized water; the two solutions are then mixed, and after thorough mixing, methyltriethoxysilane is added to form a polar solution, followed by the addition of a non-polar template solution. The mixture is stirred at a pH of 2-3 to allow methyltriethoxysilane and aluminum isopropoxide to fully hydrolyze. The pH of the mixture is then adjusted to 6-7 with ammonia. After adjustment, the mixture is allowed to stand, and the hydrophobic La-Al / SiO2 alcohol gel containing microdroplet templates is obtained. 3) Aging: Add aging solution to the alcohol gel obtained in step 2) and age it in a water bath; 4) Hexane replacement: After the gel obtained in step 3) aging is completed, crush it and add hexane and stir. Replace the hexane every once in a while, and replace it 2-4 times to remove the microdroplet template. 5) Drying: The composite alcohol gel obtained in step 4) is dried to obtain a hydrophobic La-Al / SiO2 composite aerogel.

[0009] Furthermore, in step 1), the thiophene concentration is 2 mg-S / g.

[0010] Further, in step 2), the molar ratio of aluminum isopropoxide to methyltriethoxysilane is 1:133~233, preferably 1:155; the molar ratio of lanthanum nitrate hexahydrate to methyltriethoxysilane is 1:332~996, preferably 1:498; the ratio of the total volume of acetone and water to the volume of the template agent solution (V... 丙酮+水 :V 模板剂 The ratio is 16:1.3~2.1, preferably 16:1.7.

[0011] Furthermore, the stirring time in step 2) is 3~6 hours, preferably 5 hours.

[0012] Furthermore, in step 3), the aging temperature is 40~60℃, preferably 50℃.

[0013] Furthermore, in step 3), the aging solution is composed of acetone and methyltriethoxysilane; wherein the volume ratio of acetone to methyltriethoxysilane is (V / V). 丙酮 :V MTES The ratio is 25:10~25, with 25:15 being preferred.

[0014] Furthermore, in step 4), the mass ratio of gel to n-hexane is 1:4; in step 4), n-hexane is replaced every 5 hours, for a total of 3 replacements.

[0015] Further, in step 5), the composite alcohol gel obtained in step 4) is dried at normal pressure at 100~140℃, preferably 120℃.

[0016] This invention also proposes an application of the hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent prepared by the method using the microdroplet template method, comprising the following steps: The obtained adsorbent was packed into an adsorption bed device and incubated for 2 hours. -1 The air velocity is used to introduce simulated aromatic hydrocarbons containing thiophene compounds and their derivatives into the adsorber device for adsorption, as well as to adsorb simulated aromatic hydrocarbons containing water or pyridine.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) The hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent of the present invention has strong hydrophobicity due to the presence of methyl groups on the aerogel surface, so polar substances such as water and pyridine cannot contact the active center; after eliminating the interference of polar molecules such as water or pyridine, the hydrophobic La-Al / SiO2 composite aerogel has high adsorption selectivity for thiophene compounds and their derivatives. 2) The hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent of this invention incorporates Al metal to provide Lewis acid active centers, enabling acid-base adsorption with thiophene compounds; incorporating La metal allows it to form SM bonds (S-La bonds) with sulfides in simulated aromatic hydrocarbons, achieving selective capture of sulfides. The synergistic effect of these two types of adsorption active centers further enhances the adsorption and desulfurization performance of the adsorbent. 3) Compared with hydrophobic composite aerogels prepared by doping with organic amines, the hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent prepared by the present invention has a simpler preparation process, the sol-gel process is easier to form, and the pores are more regular. 4) The hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent of the present invention is prepared by microdroplet template method. It is not only low in cost, but also easy to remove microdroplet template during washing and replacement process, and is harmless to the environment. Detailed Implementation

[0018] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the scope described.

[0019] Examples 1-5: Effect of microdroplet template dosage on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels prepared by microdroplet templates on thiophene sulfides in simulated aromatic hydrocarbons.

[0020] Example 1: A hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent was prepared by the microdroplet template method with a fixed silicon / aluminum molar ratio of 155:1. The preparation steps are as follows: 1) Thiophene was dissolved in n-heptane to prepare a mixed solution with a concentration of 2 mg-S / g, which was then used as a template solution for microdroplets; 2) Dissolve 0.03g aluminum isopropoxide in 10mL acetone; dissolve 0.02g lanthanum nitrate hexahydrate in 6mL deionized water; then mix the two solutions thoroughly, add 4.6mL methyltriethoxysilane to form a polar solution, followed by 1.7mL nonpolar template agent solution (V 丙酮+水 V 模板剂 =16:1.7), the mixed solution was stirred for 5 hours at a pH of 2-3 to allow methyltriethoxysilane and aluminum isopropoxide to be fully hydrolyzed, and then the pH was adjusted to 6-7 with ammonia water and allowed to stand for 2 hours to obtain a hydrophobic La-Al / SiO2 alcohol gel containing microdroplet template (n-heptane solution of thiophene sulfides). 3) Aging: Add 25 ml of acetone and 15 ml of n-methyltriethoxysilane to the composite alcohol gel obtained in step 2) and age it in a 50°C water bath for 14 h to enhance the skeletal structure of the gel. 4) Hexane replacement: Crush the gel obtained in step 3) and add 100 mL of hexane and stir for 2 h; replace the hexane every 5 h, and repeat 3 times to remove the microdroplet template; 5) Drying: The composite alcohol gel obtained in step 4) is dried at 120°C under normal pressure to finally obtain a hydrophobic La-Al / SiO2 composite aerogel.

[0021] Examples 2-5: The preparation method of hydrophobic La-Al / SiO2 composite aerogels is the same as in Example 1, except that the volumes of the template agent solution used in step 2) are 1.3 mL, 1.5 mL, 1.9 mL, and 2.1 mL, respectively. Wherein V丙酮+水 / V 模板剂 They are 16 / 1.3, 16 / 1.5, 16 / 1.9, and 16 / 2.1 respectively.

[0022] Comparative Example 1: The preparation method is the same as in Example 1, except that the prepared microdroplet template solution does not need to be added in step 2).

[0023] In Examples 1-5 and Comparative Example 1, the performance evaluation of adsorbing thiophene sulfides in simulated aromatics was carried out using a breakthrough adsorption experiment. The specific breakthrough adsorption experiment steps are as follows: A glass tube of a certain length was filled with degreased cotton at the bottom, followed by 1g of freshly prepared hydrophobic La-Al / SiO2 composite aerogel. Then, an appropriate amount of quartz sand was added on top of the adsorbent. The adsorbent was thoroughly wetted with n-heptane, and then incubated for 2 hours. -1 Simulated aromatic hydrocarbon SL-1 (SL-1: thiophene with a sulfur concentration of 2 mg-S / g dissolved in p-xylene, yielded as simulated aromatic hydrocarbon SL-1) was introduced at a space velocity of 100 h⁻¹. The adsorbed simulated aromatic hydrocarbon was collected at the lower end of the adsorber and subjected to chromatographic analysis. The breakthrough point was defined as a sulfur concentration of 0.005 mg-S / g in the effluent. The adsorption results are shown in Table 1.

[0024] Table 1. Dosage of microdroplet template agent (V) 丙酮+水 V 模板剂 The effect of hydrophobic La-Al / SiO2 composite aerogel on the adsorption performance of thiophene sulfides in simulated aromatic hydrocarbons.

[0025]

[0026] As shown in Table 1, with the increase of template agent dosage, the adsorption capacity of the hydrophobic La-Al / SiO2 composite aerogel for adsorbing thiophene sulfides in simulated aromatic hydrocarbons first increased and then decreased, with the best adsorption performance at 1.7 ml. Compared with the adsorbent with added template agent, the adsorbent of Comparative Example 1 (without template agent) had poorer adsorption performance, indicating that the addition of microdroplet templates can form microdroplets in the system, making the pores inside the aerogel more regular and improving the diffusion rate of the adsorbate. In addition, due to the guiding and enrichment effect of S atoms in thiophene compounds in the template agent, Al 3+ La 3+ Active sites can be enriched on the inner surface of the polymer backbone of the aerogel and fully exposed, thus improving the adsorption performance of the adsorbent.

[0027] Examples 6-9: Effect of silicon / aluminum molar ratio on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0028] The preparation method was the same as in Example 1, except that the amount of aluminum isopropoxide added in step 2) was 0.02 g, 0.025 g, 0.03 g, and 0.035 g, respectively, so that the Si / Al molar ratios in Examples 6-9 were 233:1, 187:1, 155:1, and 133:1, respectively. Specific results are shown in Table 2.

[0029] Table 2. Effect of different silicon / aluminum molar ratios on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0030]

[0031] As shown in Table 2, as the silicon / aluminum molar ratio decreases, the adsorption capacity of the hydrophobic La-Al / SiO2 composite aerogel for adsorbing thiophene sulfides in simulated aromatic hydrocarbons first increases and then decreases. When the added aluminum isopropoxide is 0.03 g, that is, the silicon / aluminum molar ratio is 155:1, the adsorption performance is optimal.

[0032] Examples 10-14: Effect of silicon / lanthanum molar ratio on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0033] The preparation method was the same as in Example 8, except that 0.01 g, 0.015 g, 0.02 g, 0.025 g, and 0.03 g of lanthanum nitrate hexahydrate were added in step 2), resulting in Si / La molar ratios of 996:1, 664:1, 498:1, 398:1, and 332:1 in Examples 10-14, respectively. Specific results are shown in Table 3.

[0034] Table 3. Effect of different silicon / lanthanum molar ratios on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0035]

[0036] As shown in Table 3, as the silicon / lanthanum molar ratio decreases, the adsorption capacity of the hydrophobic La-Al / SiO2 composite aerogel for adsorbing thiophene sulfides in simulated aromatic hydrocarbons first increases and then decreases. When the added lanthanum nitrate hexahydrate is 0.02 g, that is, the silicon / lanthanum molar ratio is 498:1, the adsorption performance is optimal.

[0037] Examples 15-18: Effect of stirring time of mixed solution on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogel on thiophene sulfides in simulated aromatic hydrocarbons.

[0038] The preparation method is the same as in Example 12, except that the stirring time in step 2) is 3h, 4h, 5h and 6h respectively.

[0039] The adsorbents prepared in Examples 15-18 were evaluated using the same methods as in Example 12. Specific results are shown in Table 4.

[0040] Table 4 shows the effect of different stirring times on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0041]

[0042] As shown in Table 4, with the increase of stirring time, the penetration adsorption capacity of hydrophobic La-Al / SiO2 composite aerogel for thiophene first increases and then decreases, reaching the optimal value when the stirring time is 5h.

[0043] Examples 19-21: Effect of aerogel aging temperature on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0044] The preparation method is the same as in Example 17, except that the aging temperatures in step 3) are 40°C, 50°C, and 60°C, respectively.

[0045] The adsorbents prepared in Examples 19-21 were evaluated using the same methods as in Example 17. Specific results are shown in Table 5.

[0046] Table 5. Effect of different aging temperatures on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0047]

[0048] As shown in Table 5, with the increase of aging temperature, the penetration adsorption capacity of hydrophobic La-Al / SiO2 composite aerogel for thiophene first increases and then decreases, reaching the optimal value when the aging temperature is 50℃.

[0049] Examples 22-25: Different aging liquid volume ratios (V) 丙酮 :V MTES The effect of hydrophobic La-Al / SiO2 composite aerogel on the adsorption performance of thiophene sulfides in simulated aromatic hydrocarbons.

[0050] The preparation method is the same as in Example 20, except that the amount of methyltriethoxysilane added in step 3) is 10 mL, 15 mL, 20 mL, and 25 mL, respectively, to obtain the volume ratio (V) of acetone to methyltriethoxysilane in the aging solution. 丙酮 :V MTES The hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbents have ratios of 25:10, 25:15, 25:20, and 25:25, respectively.

[0051] The adsorbents prepared in Examples 22-25 were evaluated using the same methods as in Example 20. Specific results are shown in Table 6.

[0052] Table 6 Aging liquid volume ratio (V) 丙酮 :V MTES The effect of hydrophobic La-Al / SiO2 composite aerogel on the adsorption performance of thiophene sulfides in simulated aromatic hydrocarbons.

[0053]

[0054] As shown in Table 6, with the increase of methyltriethoxysilane solution in the aging solution, the penetration adsorption capacity of hydrophobic La-Al / SiO2 composite aerogel for thiophene first increases and then decreases, reaching the optimal value when the methyltriethoxysilane solution is 15 mL.

[0055] Examples 26-28: Effect of different drying temperatures on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0056] The preparation method is the same as in Example 23, except that the drying temperatures in step 5) are 100℃, 120℃, and 140℃, respectively.

[0057] The adsorbents prepared in Examples 26-28 were evaluated using the same methods as in Example 23. Specific results are shown in Table 7.

[0058] Table 7. Effect of different drying temperatures on the adsorption performance of hydrophobic La-Al / SiO2 composite aerogels on thiophene sulfides in simulated aromatic hydrocarbons.

[0059]

[0060] As shown in Table 7, with the increase of drying temperature, the penetration adsorption capacity of hydrophobic La-Al / SiO2 composite aerogel for thiophene first increases and then decreases, reaching the optimal value when the drying temperature is 120℃.

[0061] Examples 29-30: Effects of hydrophobic La-Al / SiO2 composite aerogel adsorbent prepared by microdroplet template method on the adsorption performance of thiophene compounds in the presence of water and pyridine in simulated aromatic hydrocarbons.

[0062] The adsorbent used was the same as in Example 27, and its breakthrough adsorption experiment was the same as in Example 27. The difference was that the simulated aromatic hydrocarbons used were SL-2 and SL-3 respectively (SL-2: p-xylene + 0.525wt% thiophene + 1.0wt% water; SL-3: p-xylene + 0.525wt% thiophene + 1.0wt% pyridine).

[0063] Comparative Example 2: The preparation method is the same as in Example 27, except that in Comparative Example 1, methyltriethoxysilane in steps 2) and 3) is replaced with tetraethyl orthosilicate, acetone is replaced with anhydrous ethanol, and the amount of tetraethyl orthosilicate, deionized water, lanthanum nitrate hexahydrate, and aluminum isopropoxide added in step 2) is 8 mL, 2 mL, 0.031 g, and 0.047 g, to prepare a hydrophilic La-Al / SiO2 composite aerogel adsorbent with a silicon / lanthanum molar ratio of 498:1 and a silicon / aluminum molar ratio of 155:1. The simulated aromatic hydrocarbon used is SL-1, and the breakthrough adsorption results are shown in Table 8.

[0064] Comparative Examples 3-4: The preparation method is the same as that of Comparative Example 2, and the breakthrough adsorption experiment is the same as that of Example 27. The difference is that the simulated aromatic hydrocarbons used are SL-2 and SL-3 respectively. The breakthrough adsorption results are shown in Table 8.

[0065] The breakthrough adsorption results of Examples 27, 29 and 30 and Comparative Examples 2 to 4 are shown in Table 8.

[0066] Table 8. Effects of the presence of water and pyridine in simulated aromatic hydrocarbons on the desulfurization and adsorption performance of hydrophilic / hydrophobic La-Al / SiO2 composite aerogels prepared by the microdroplet template method.

[0067]

[0068] As shown in Table 8, when water and pyridine are present in the simulated aromatic hydrocarbons, the adsorption capacity of both types of composite aerogel adsorbents for thiophene sulfides is reduced. However, compared with the hydrophilic La-Al / SiO2 composite aerogel, the hydrophobic La-Al / SiO2 composite aerogel prepared by the microdroplet template method shows superior adsorption selectivity for thiophene in the simulated aromatic hydrocarbons.

Claims

1. A method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent using a microdroplet template method, characterized in that... This composite aerogel was prepared using a microdroplet template method based on a sol-gel combined atmospheric pressure drying method; the specific steps include the following: 1) Preparation of microdroplet template solution: Thiophene compounds are dissolved in n-heptane to form a template solution; 2) Preparation of hydrophobic alcohol gel containing microdroplet templates: Aluminum isopropoxide is dissolved in acetone; lanthanum nitrate hexahydrate is dissolved in deionized water; the two solutions are then mixed, and after thorough mixing, methyltriethoxysilane is added to form a polar solution, followed by the addition of a non-polar template solution. The mixture is stirred at a pH of 2-3 to allow methyltriethoxysilane and aluminum isopropoxide to fully hydrolyze. The pH of the mixture is then adjusted to 6-7 with ammonia. After adjustment, the mixture is allowed to stand, and the hydrophobic La-Al / SiO2 alcohol gel containing microdroplet templates is obtained. 3) Aging: Add aging solution to the alcohol gel obtained in step 2) and age it in a water bath; 4) Hexane replacement: After the gel obtained in step 3) aging is completed, crush it and add hexane and stir. Replace the hexane every once in a while, and replace it 2-4 times to remove the microdroplet template. 5) Drying: The composite alcohol gel obtained in step 4) is dried to obtain a hydrophobic La-Al / SiO2 composite aerogel.

2. The method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent using a microdroplet template method according to claim 1, characterized in that... In step 1), the thiophene concentration is 2 mg-S / g.

3. The method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent using a microdroplet template method according to claim 1, characterized in that... In step 2), the molar ratio of aluminum isopropoxide to methyltriethoxysilane is 1:133~233, preferably 1:155; the molar ratio of lanthanum nitrate hexahydrate to methyltriethoxysilane is 1:332~996, preferably 1:498; and the ratio of the total volume of acetone and water to the volume of the template agent solution is 16:1.3~2.1, preferably 16:1.

7.

4. The method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent using a microdroplet template method according to claim 1, characterized in that... The stirring time in step 2) is 3 to 6 hours, preferably 5 hours.

5. The method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent using a microdroplet template method according to claim 1, characterized in that... In step 3), the aging temperature is 40~60℃, preferably 50℃.

6. The method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent by microdroplet template method according to claim 1, characterized in that... In step 3), the aging solution is composed of acetone and methyltriethoxysilane; wherein the volume ratio of acetone to methyltriethoxysilane is 25:10~25, preferably 25:

15.

7. The method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent by microdroplet template method according to claim 1, characterized in that... In step 4), the mass ratio of gel to hexane is 1:4; in step 4), the hexane is replaced every 5 hours, for a total of 3 replacements.

8. The method for preparing hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent by microdroplet template method according to claim 1, characterized in that... In step 5), the composite alcohol gel obtained in step 4) is dried at 100~140℃ under normal pressure, preferably 120℃.

9. An application of a hydrophobic La-Al / SiO2 composite aerogel desulfurization adsorbent prepared by the method according to any one of claims 1-8 using the microdroplet template method, characterized in that... Includes the following steps: The obtained adsorbent was packed into an adsorption bed device and incubated for 2 hours. -1 The air velocity is used to introduce simulated aromatic hydrocarbons containing thiophene compounds and their derivatives into the adsorber device for adsorption, as well as to adsorb simulated aromatic hydrocarbons containing water or pyridine.

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