A method for preparing a core-shell structured organic oxide adsorbent

Abstract

This invention discloses a method for preparing a core-shell structured organic oxide adsorbent, particularly for applications in efficient deoxygenation processes. The method involves reacting a coupling agent with a 13X molecular sieve in an alcohol solvent, followed by high-temperature calcination and immersion in a copper salt solution. The resulting precursor sol is then reacted with a titanium source to form an organic oxide adsorbent with excellent adsorption properties. Furthermore, a method for preparing the 13X molecular sieve is proposed. Through precise control of pH, crystallization temperature, and raw material ratios, along with a two-stage crystallization process, a molecular sieve with a high silica-to-alumina ratio, excellent specific surface area, and pore capacity is obtained. The adsorbent prepared by this invention exhibits excellent chemical and thermal stability, as well as high adsorption efficiency for oxides. It not only demonstrates superior performance in the removal of oxides from high-carbon alkanes and alkenes produced by Fischer-Tropsch synthesis but is also suitable for the efficient removal of oxides from a wide range of hydrocarbon fuels and chemical products.

Description

Technical Field

[0001] This invention belongs to the field of chemical synthesis, specifically relating to a method for preparing an organic oxide adsorbent based on a core-shell structure. Background Technology

[0002] Molecular sieves are aluminosilicates with uniform pore size, regular crystal structure, abundant pore system, large specific surface area, and good thermal stability, making them a preferred adsorbent material for removing oxygen-containing compounds from olefins. FAU-type (X and Y-type) molecular sieves have a pore size of approximately 0.74 nm. X-type molecular sieves, in particular, are well-researched for removing oxygen-containing compound impurities from olefins and have been applied in industrial practice. However, their adsorption heat is high when used for olefin purification, often requiring pre-loading, and some olefins are adsorbed during the purification process. Therefore, research and development of X-type molecular sieve adsorbents focuses on three aspects: selective adsorption of oxygen-containing compounds while minimizing olefin adsorption; effective reduction of adsorption heat; and effective increase of adsorbent adsorption capacity and purification depth. Adsorption methods for separating substances have been widely used in petroleum cracking and refinery catalytic cracking. Current research on adsorption separation technology mainly focuses on the adsorption method for removing oxides from C4 and above hydrocarbons. However, the hydrocarbon products generated by the indirect liquefaction of coal through Fischer-Tropsch synthesis exhibit different carbon number distributions, and the oxygen-containing compounds within these products are diverse, with significant differences in molecular weight and structure. Furthermore, the pore size and composition of commonly used molecular sieves also vary. Therefore, there is no single adsorbent suitable for separating oxides from Fischer-Tropsch products with all carbon number distributions. Consequently, adsorbents with uniform and ordered micropores, large specific surface area, high adsorption capacity, and low heat of adsorption have broad application prospects in adsorption separation and other fields. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a method for preparing an organic oxide adsorbent based on a core-shell structure, the details of which are as follows:

[0004] A method for preparing an organic oxide adsorbent based on a core-shell structure, characterized in that: 13X molecular sieve and a coupling agent (isopropyltrimethoxysilane, vinyltrimethoxysilane, ethyl orthosilicate, ethoxysilane, ethyl orthosilicate) are added to an alcohol solvent (ethanol, propanol, butanol); the resulting reactants are subjected to solid-liquid separation, followed by calcination at high temperature; the calcined molecular sieve is immersed in a copper salt (copper nitrate, copper chloride, copper acetate) solution; a titanium source (tetrabutyl titanate, titanium orthosilicate, diisopropoxydiacetylacetonate titanium), ethanol, and water are thoroughly mixed to form a precursor sol; the molecular sieve and the precursor sol are mixed and stirred to form a mixture; the mixture is dried, followed by high-temperature calcination in a kiln; the calcined product is dried using a vacuum drying device to obtain the organic oxide adsorbent.

[0005] A method for preparing a 13X molecular sieve with a core-shell structure, characterized by the following steps: (1) mixing a silicon source and water evenly to obtain a silicon-containing material, and mixing an aluminum source and water evenly to obtain an aluminum-containing material; (2) slowly adding the aluminum-containing material dropwise to the silicon-containing material, stirring for a period of time to obtain a mixture gel, adjusting the pH of the mixture gel to 8.5-12.5, and then performing a two-stage hydrothermal crystallization treatment to obtain a crystallized product; (3) performing aluminum-dissolving and silicon-dissolving treatments on the molecular sieve-containing material to obtain a silicon-rich liquid and an aluminum-rich liquid, and mixing the two to obtain a gel-like mother liquor; (4) adding the crystallized product from step (2) to the gel-like mother liquor from step (3), aging the product, and then performing a hydrothermal crystallization treatment, filtering and washing the reaction product, and then drying it to obtain a 13X molecular sieve. (5) The 13X molecular sieve powder was soaked in a solution containing 3-aminopropyltriethoxysilane (APTES) for 8 hours; the treated 13X molecular sieve powder was then soaked in a 0.1M nickel nitrate solution for 24 hours; calcined at 500°C for 2 hours in a hydrogen atmosphere to form a nickel nanoparticle deposition layer on the outside of the 13X molecular sieve; the raw materials were mixed in a molar ratio of SiO2:TiO2:template agent:fluorine complex:water = 1:(0.04-0.1):(0.1-0.3):(0.03-0.06):(20-50) to prepare a precursor solution; the 13X molecular sieve with nickel nanoparticle deposition was added to the titanium-silicon molecular sieve precursor solution, and after thorough mixing, it was transferred to a reaction vessel and subjected to a hydrothermal reaction at 150°C for 12 hours; after the reaction was completed, the solid was removed and washed with water, then dried at 110°C for 12 hours and calcined at 450°C for 4 hours to form a core-shell molecular sieve. The template agent is an organic amine or a quaternary ammonium salt.

[0006] In the method of this invention, the silicon source in step (1) is selected from one or more of silica sol, tetraethyl orthosilicate, coarse-porous silica gel, silica powder, fly ash, and silica. The mixing process of the silicon source and water is generally carried out at 20-60°C for 0.1-12 hours, with the stirring speed maintained at 200-800 rpm, to obtain a silicon-containing material, the concentration of which is generally 28%-99 wt%.

[0007] In the method of this invention, the aluminum source in step (1) is selected from one or more of sodium aluminate, boehmite, aluminum sulfate, and aluminum nitrate. The mixing process of the aluminum source and water is generally carried out at 20-60°C for 0.1-12 hours, and the stirring speed is preferably 200-800 rpm, to obtain an aluminum-containing material with a concentration of 15%-99% wt%.

[0008] In the method of the present invention, the stirring conditions described in step (2) are generally stirred at 20 to 100°C for 0.1 to 24 hours to obtain a mixture gel.

[0009] In the method of the present invention, the pH adjustment method described in step (2) can be achieved by slowly adding a solid alkali or an aqueous solution of alkali to the gel solution A.

[0010] In the method of this invention, the two-stage crystallization conditions in step (2) are as follows: the first-stage crystallization temperature is 20–60°C, and the crystallization time is 4–24 h; the second-stage crystallization temperature is 80–120°C, and the crystallization time is 6–48 h; crystallization is generally carried out in a hydrothermal reactor; the second stage is 20°C higher than the first stage.

[0011] In the method of the present invention, the molar ratios of the components in the crystallized product obtained in step (2) are SiO2 / Al2O3 = (0.1~2.5):1, Na2O / SiO2 = (0.1~4.0):1, and H2O / SiO2 = (1.0~40.0):1.

[0012] In the method of the present invention, the molecular sieve-containing material in step (3) is selected from one or more of the following: waste Z-5 molecular sieve catalyst, waste MTO catalyst, waste molecular sieve adsorbent, fly ash, waste FCC catalyst, and waste VOC adsorbent.

[0013] In the method of the present invention, the aluminum dissolution and silicon dissolution processes in step (3) are as follows: the molecular sieve material is ground to a sample of less than 200 mesh, mixed with NaCO3 at a mass ratio of 1:0.5 to 1:5, and calcined at 550-800℃ for 60-120 min. Then, the calcined product is dissolved and filtered with a monobasic acid of 10%-35% by mass to obtain an aluminum-rich liquid. The residue obtained is mixed with NaOH:H2O at a mass ratio of 1.5-100:40-60:50-400, stirred and mixed evenly, and filtered to obtain a silicon-rich liquid. Finally, the silicon-rich liquid and the aluminum-rich liquid are mixed to obtain a gel-like mother liquor. The molar ratio of each component in the gel-like mother liquor is: SiO2 / Al2O3 = 0.5-6.0:1, Na2O / SiO2 = 0.5-6.0:1, H2O / SiO2 = 10-100:1.

[0014] In the method of the present invention, the amount of crystallized product added in step (4) accounts for 5wt%-20wt% of the gel mother liquor.

[0015] In the method of the present invention, the aging conditions in step (4) are: aging temperature of 20 to 100°C, aging time of 0.1 to 24 hours, and the aging process is generally carried out under stirring conditions.

[0016] In the method of the present invention, the hydrothermal crystallization conditions in step (4) are: crystallization temperature of 60-105℃ and crystallization time of 0.1-36h.

[0017] In the method of the present invention, step (4) involves filtering and washing the reaction product until it is neutral, and then drying it at 80-120°C until there is no significant weight loss to obtain 13X molecular sieve.

[0018] By precisely controlling the pH, the temperature and time of the two-stage crystallization, and the raw material ratio, the synergistic effect can be used to regulate the pore volume and specific surface area, and molecular sieves with suitable pore volume and specific surface area can be prepared as needed.

[0019] The 13X molecular sieve prepared by the method of this invention has the following properties: a silica-to-alumina ratio of 2.2–2.9 and a pore volume of 0.3 cm³. 3 / g~0.5cm 3 / g, specific surface area 700m² 2 / g~950m 2 / g. The 13X molecular sieve prepared in this invention has a high silicon-to-aluminum ratio, high silicon source utilization, and good selectivity. It can be regulated according to different adsorbed molecules, providing more adsorption sites, introducing mesoporous channels, and increasing the pore volume inside the molecular sieve crystal, thereby significantly reducing the carbon deposition rate of the molecular sieve and improving the diffusion performance of the adsorbent. Based on this molecular sieve, the surface and structure of the molecular sieve are modified by introducing a coupling agent and impregnating with metal ions, thereby obtaining an improved adsorbent. This adsorbent has excellent high adsorption efficiency, not only performing well in the removal of oxides from high-carbon alkanes and alkenes produced by Fischer-Tropsch synthesis, but also suitable for the efficient removal of oxides from a wide range of hydrocarbon fuels or chemical products. Detailed Implementation

[0020] The present invention will be described in detail below through embodiments. Each embodiment only lists key technical indicators, but the present invention is not limited to these embodiments.

[0021] Example 1:

[0022] (1) Seed preparation: 21.0g of silica sol (silica mass fraction of 30%) was dissolved in 36.0g of deionized water and pretreated in a closed reactor at 25℃ and 500rpm for 1 hour to obtain a dispersed aqueous solution of silicon source; 24g of aluminum sulfate was dissolved in 18.0g of deionized water and stirred at 25℃ and 500rpm for 1 hour to obtain a dispersed aqueous solution of aluminum source; the aqueous solution of aluminum source was slowly added dropwise to the aqueous solution of silicon source and stirred at 60℃ for 8 hours to obtain a gel solution; 6.74g of sodium hydroxide was dissolved in 36g of deionized water dispersion and added to the gel solution, and the pH value was maintained at 12.2. The gel solution was placed in a hydrothermal reactor for two-stage temperature-controlled crystallization. The first stage crystallization temperature was 40℃ and the time was 12 hours, and the second stage crystallization temperature was 95℃ and the time was 24 hours. Deionized water was added as needed during the crystallization process to obtain a seed solution.

[0023] (2) Grind the fly ash to below 200 mesh, mix the ground fly ash with NaCO3 at a mass ratio of 1:2.5, calcine at 700℃ for 90 min, dissolve the calcined product with 25% hydrochloric acid, filter to obtain aluminum-rich liquid and residue; mix the residue with NaOH and H2O at a mass ratio of 50:50:200, filter to obtain silicon-rich liquid; weigh the silicon-rich liquid and aluminum-rich liquid according to the molar ratio of SiO2 / Al2O3 = 3.5:1, Na2O / SiO2 = 2.8:1, H2O / SiO2 = 80:1 to obtain gel-like mother liquor;

[0024] (3) Taking the mass of the gel mother liquor as 100%, add 15% of a solution containing 13X molecular sieve seed crystals to the gel mother liquor prepared in step (2), age it at 60°C for 12 hours, and then perform hydrothermal crystallization treatment at 80°C for 12 hours. Filter the hydrothermal crystallization product, wash it until neutral, and dry it at 100°C to constant weight to obtain 13X molecular sieve.

[0025] (4) Preparation of core-shell structured 13X molecular sieve: 100g of the above-mentioned 13X molecular sieve powder was placed in 200mL of 0.1mol / L 3-aminopropyltriethoxysilane solution for a first impregnation treatment for 8 hours; then, the treated 13X molecular sieve was placed in 0.1mol / L nickel nitrate solution for a second impregnation treatment for 24 hours; the 13X molecular sieve after the second impregnation treatment was calcined in a hydrogen atmosphere at 500℃ for 2 hours to obtain nickel-modified 13X molecular sieve containing a nickel nanoparticle deposition layer. SiO2, TiO2, template agent, fluorine complex and water were mixed to prepare... A titanium-silicon molecular sieve precursor solution was prepared, wherein the molar ratio of SiO2, TiO2, template agent, fluorine complex, and water was 1:0.06:0.2:0.04:30. 50 g of 13X molecular sieve containing a nickel nanoparticle deposition layer was added to 150 mL of the titanium-silicon molecular sieve precursor solution. After thorough mixing, the mixture was transferred to a reactor for a first hydrothermal reaction at 150 °C for 12 h. After the reaction was completed, the solid was removed and washed with water, then dried at 110 °C for 12 h. The dried solid was then calcined at 450 °C for 4 h to obtain a core-shell structured 13X molecular sieve.

[0026] (5) 50g of coated 13X molecular sieve and 0.5g of methyltriethoxysilane were added to 49.5g of anhydrous ethanol and stirred at room temperature for 4 hours. The mixture was then filtered and calcined at 450℃ for 2 hours. The calcined 13X molecular sieve was then immersed in a 1mol / L copper nitrate aqueous solution at room temperature for 24 hours. 10g of tetrabutyl titanate was slowly added dropwise to a mixed solvent of 50g ethanol and 10g distilled water and stirred at 60℃ for 3 hours to obtain a titanium precursor sol. The 13X molecular sieve soaked in the copper salt solution was added to the titanium precursor sol and stirred evenly. The mixture was dried at 100℃ for 12 hours and then heated to 500℃ at a heating rate of 5℃ / min in a kiln for 2 hours. The calcined product was dried in a vacuum drying device for 12 hours to finally obtain an organic oxide adsorbent.

[0027] Example 2:

[0028] (1) Dissolve 1g of silicon powder in 18g of deionized water and pretreat it in a sealed reactor at 25°C and 500rpm for 1 hour to obtain a silicon source dispersed phase aqueous solution; dissolve 12g of aluminum nitrate in 18.0g of deionized water and stir at 35°C and 500rpm for 1 hour to prepare an aluminum source dispersed phase aqueous solution. Slowly add the prepared aluminum source aqueous solution to the silicon source aqueous solution and continue stirring at 50°C for 6 hours to obtain a gel solution; dissolve 2g of sodium hydroxide in 36g of deionized water to obtain a dispersion, and slowly add it to the gel solution, controlling the pH value at 11.8. Then, transfer the mixed gel solution to a hydrothermal reactor and perform a two-stage temperature-controlled crystallization process: the first stage crystallization temperature is set at 50°C for 14 hours; the second stage crystallization temperature is controlled at 100°C for 18 hours. During the crystallization process, deionized water is added as needed to obtain a seed crystal solution.

[0029] (2) Grind the Z-5 molecular sieve catalyst to below 200 mesh, mix the ground Z-5 molecular sieve catalyst with NaCO3 at a mass ratio of 1:0.5, calcine at 550℃ for 60 min, dissolve the calcined product with acetic acid of 35% mass fraction, filter to obtain aluminum-rich liquid and residue; mix the residue with NaOH and H2O at a mass ratio of 5:40:50, filter to obtain silicon-rich liquid; weigh the silicon-rich liquid and aluminum-rich liquid according to the molar ratio of SiO2 / Al2O3 = 6:1, Na2O / SiO2 = 0.5:1, H2O / SiO2 = 100:1 to obtain gel-like mother liquor.

[0030] (3) Taking the mass of the gel mother liquor as 100%, add 5% of the mass of the solution containing 13X molecular sieve seed crystals to the gel mother liquor prepared in step (2), age it at 20°C for 0.1h, and then perform hydrothermal crystallization treatment at 60°C for 0.1h. Filter and wash the hydrothermal crystallization product until it is neutral, and dry it at 80°C to constant weight to obtain 13X molecular sieve.

[0031] (4) Preparation of core-shell structured 13X molecular sieve: 100g of the above-mentioned 13X molecular sieve powder was placed in 200mL of 0.1mol / L 3-aminopropyltriethoxysilane solution for a first impregnation treatment for 12 hours; then, the treated 13X molecular sieve was placed in 0.1mol / L nickel nitrate solution for a second impregnation treatment for 30 hours; the 13X molecular sieve after the second impregnation treatment was calcined in a hydrogen atmosphere at 600℃ for 3 hours to obtain a nickel-modified 13X molecular sieve containing a nickel nanoparticle deposition layer. SiO2, TiO2, template agent, fluorine complex and water were mixed to prepare... A titanium-silicon molecular sieve precursor solution was prepared, wherein the molar ratio of SiO2, TiO2, template agent, fluorine complex, and water was 1:0.1:0.3:0.06:50. 50g of 13X molecular sieve containing a nickel nanoparticle deposition layer was added to 150mL of the titanium-silicon molecular sieve precursor solution. After thorough mixing, the mixture was transferred to a reactor for a first hydrothermal reaction at 200℃ for 16h. After the reaction was completed, the solid was removed and washed with water, then dried at 150℃ for 24h. The dried solid was then calcined at 500℃ for 6h to obtain a core-shell structured 13X molecular sieve.

[0032] (5) 50g of coated 13X molecular sieve and 0.1g of isopropyltrimethoxysilane were added to 40g of anhydrous ethanol and stirred at 15°C for 1 hour. The mixture was then filtered, and the filtered molecular sieve was calcined at 400°C for 0.5 hours. The calcined 13X molecular sieve was then immersed in a 0.1mol / L copper chloride aqueous solution at room temperature for 24 hours. 10g of titanium orthosilicate was slowly added dropwise to a mixed solvent of 30g ethanol and 5g distilled water and stirred at 50°C for 1 hour to obtain a titanium precursor sol. The 13X molecular sieve immersed in the copper salt solution was added to the titanium precursor sol and stirred until homogeneous. The mixture was then dried at 90°C for 6 hours and then heated to 450°C in a kiln at a heating rate of 5°C / min for 0.5 hours. The calcined product was dried in a vacuum drying device for 12 hours to obtain the organic oxide adsorbent.

[0033] Example 3:

[0034] (1) Seed crystal preparation: 0.17g of silicon powder was dissolved in 6g of deionized water and pretreated in a sealed reactor at 25℃ and 200rpm for 1 hour to obtain a silicon source dispersed phase aqueous solution; 12g of aluminum nitrate was dissolved in 18.0g of deionized water and stirred at 35℃ and 200rpm for 1 hour to prepare an aluminum source dispersed phase aqueous solution. The aluminum source solution was slowly added to the silicon source solution and stirred at 100℃ for 24 hours to obtain a gel solution; 0.9g of sodium hydroxide was dissolved in 6g of deionized water to prepare a dispersion, which was then slowly added to gel solution E, and the pH value was adjusted to 12.5. The prepared gel was then poured into a hydrothermal reactor for two-stage crystallization. First, crystallization was carried out at 60℃ for 24 hours, and then the temperature was increased to 120℃ for 48 hours. Deionized water was added as needed during the crystallization process to obtain a seed crystal solution.

[0035] (2) Grind the waste MTO catalyst to below 200 mesh, mix the ground waste MTO catalyst with NaCO3 at a mass ratio of 1:5, calcine at 800℃ for 120 min, dissolve the calcined product with 10% nitric acid, filter to obtain aluminum-rich liquid and residue; mix the residue with NaOH and H2O at a mass ratio of 100:60:400, filter to obtain silicon-rich liquid; weigh the silicon-rich liquid and aluminum-rich liquid according to the molar ratio of SiO2 / Al2O3 = 0.5:1, Na2O / SiO2 = 6.0:1, H2O / SiO2 = 10:1 to obtain gel-like mother liquor.

[0036] (3) Taking the mass of the gel mother liquor as 100%, add 20% of the mass of the solution containing 13X molecular sieve seed crystals to the gel mother liquor prepared in step (2), age it at 100°C for 24 hours, and then perform hydrothermal crystallization treatment at 105°C for 36 hours. Filter the hydrothermal crystallization product, wash it until neutral, and dry it at 120°C to constant weight to obtain 13X molecular sieve.

[0037] (4) Preparation of core-shell structured 13X molecular sieve: 100g of the above-mentioned 13X molecular sieve powder was placed in 200mL of 0.1mol / L 3-aminopropyltriethoxysilane solution for a first impregnation treatment for 6 hours; then the treated 13X molecular sieve was placed in 0.1mol / L nickel nitrate solution for a second impregnation treatment for 16 hours; the 13X molecular sieve after the second impregnation treatment was calcined in a hydrogen atmosphere at 400℃ for 1 hour to obtain nickel-modified 13X molecular sieve containing a nickel nanoparticle deposition layer. SiO2, TiO2, template agent, fluorine complex and water were mixed. A titanium-silicon molecular sieve precursor solution was prepared, wherein the molar ratio of SiO2, TiO2, template agent, fluorine complex, and water was 1:0.04:0.1:0.03:20. 50 g of 13X molecular sieve containing a nickel nanoparticle deposition layer was added to 150 mL of the titanium-silicon molecular sieve precursor solution. After thorough mixing, the mixture was transferred to a reactor for a first hydrothermal reaction at 100 °C for 8 h. After the reaction was completed, the solid was removed and washed with water, then dried at 80 °C for 8 h. The dried solid was then calcined at 300 °C for 3 h to obtain a core-shell structured 13X molecular sieve.

[0038] (5) 50g of coated 13X molecular sieve and 2.5g of tetraethyl orthosilicate were added to 100g of anhydrous ethanol and stirred at 40°C for 10 hours. The mixture was then filtered, and the filtered molecular sieve was calcined at 500°C for 4 hours. The calcined 13X molecular sieve was then immersed in 2L of copper acetate aqueous solution at room temperature for 24 hours. 10g of titanium diisopropoxydiacetylacetone was slowly added dropwise to a mixed solvent of 70g ethanol and 15g distilled water and stirred at 70°C for 6 hours to obtain a titanium precursor sol. The 13X molecular sieve soaked in the copper salt solution was added to the titanium precursor sol and stirred evenly. The mixture was dried at 110°C for 18 hours, and then heated to 550°C in a kiln at a heating rate of 5°C / min for 4 hours. The calcined product was dried in a vacuum drying device for 12 hours to finally obtain the organic oxide adsorbent.

[0039] Example 4:

[0040] The only difference between it and Example 1 is that step (1) is different, as follows:

[0041] (1) Seed preparation: 14.65g of tetraethyl orthosilicate and 36g of deionized water were mixed and pretreated in a sealed reactor at 25°C and 800rpm for 1 hour to obtain a silicon source dispersed phase aqueous solution; 12g of aluminum nitrate was dissolved in 18.0g of deionized water and stirred at 35°C and 800rpm for 1 hour to obtain an aluminum source dispersed phase aqueous solution. The aluminum source solution was gradually added dropwise to the silicon source solution and mixed and stirred at 20°C for 0.1 hours to prepare a gel solution; 0.56g of sodium hydroxide was dissolved in 6g of deionized water as a dispersion liquid and slowly poured into the gel solution, maintaining the pH value at 8.5. The prepared gel was introduced into a hydrothermal reactor to perform a segmented crystallization reaction: first, the crystallization temperature was set at 20°C and maintained for 4 hours; then, it was increased to 80°C and maintained for 6 hours. Deionized water was added as needed during the crystallization process to obtain a seed solution.

[0042] Table 1

[0043]

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0045] Matters not covered in this invention are common knowledge.

Claims

1. A method for preparing an organic oxide adsorbent based on a core-shell structure, characterized in that, The method includes the following steps: (1) Mix silicon source and water evenly to obtain silicon-containing material, and mix aluminum source and water evenly to obtain aluminum-containing material; (2) Slowly add aluminum-containing material to silicon-containing material, continue stirring for a period of time to obtain mixture gel, adjust the pH value of mixture gel to 8.5-12.5, and then perform two-stage hydrothermal crystallization treatment to obtain crystallization product; (3) Perform aluminum dissolution and silicon dissolution treatment on molecular sieve material to obtain aluminum-rich liquid and silicon-rich liquid, and mix the two to obtain gel-like mother liquor; (4) Add the crystallization product of step (2) to the gel-like mother liquor of step (3), perform aging treatment, and then perform hydrothermal crystallization treatment. The reaction product is filtered, washed, and then dried to obtain 13X molecular sieve; (5) Soak the 13X molecular sieve powder in a solution containing 3-aminopropyltriethoxysilane for 6-12 hours; then soak the treated 13X molecular sieve powder in 0.1M nickel nitrate solution for 16-30 hours; (5) Calcine at 400-600℃ for 1-3 hours in a hydrogen atmosphere to form a nickel nanoparticle deposition layer on the outside of the 13X molecular sieve; (6) Prepare a titanium-silicon molecular sieve precursor solution by mixing raw materials in a molar ratio of SiO2:TiO2:template agent:fluorine complex:water = 1:(0.04-0.1):(0.1-0.3):(0.03-0.06):(20-50); Add the 13X molecular sieve with nickel nanoparticle deposition to the titanium-silicon molecular sieve precursor solution, mix thoroughly, transfer to a reaction vessel, and carry out a hydrothermal reaction at 100-200℃ for 8-16 hours; After the reaction is completed, take out the solid and wash it with water, then dry it at 80-150℃ for 8-24 hours, and calcine it at 300-500℃ for 3-6 hours to form a core-shell structure 13X molecular sieve; wherein, the template agent is an organic amine or a quaternary ammonium salt; (7) The core-shell structured 13X molecular sieve and the coupling agent are added to an alcohol solvent; the resulting reactants are subjected to solid-liquid separation and then calcined at high temperature; the calcined core-shell structured 13X molecular sieve is immersed in a copper salt solution; a precursor sol is formed by thoroughly mixing a titanium source, ethanol and water; the core-shell structured 13X molecular sieve immersed in the copper salt solution is mixed and stirred with the precursor sol to form a mixture; the mixture is dried and then calcined at high temperature in a kiln; the calcined product is dried using a vacuum drying device to obtain an organic oxide adsorbent; The coupling agent is one of isopropyltrimethoxysilane, vinyltrimethoxysilane, ethyl orthosilicate, ethoxysilane, or tetraethyl orthosilicate; The alcohol solvent is one of ethanol, propanol, or butanol; The copper salt is one of copper nitrate, copper chloride, or copper acetate; The titanium source mentioned in step (7) is one of tetrabutyl titanate, titanium orthosilicate, or titanium diisopropoxydiacetylacetonate.

2. The method according to claim 1, characterized in that, The silicon source mentioned in step (1) is selected from one or more of silica sol, tetraethyl orthosilicate, coarse-porous silica gel, silica powder, fly ash, and silica. The aluminum source mentioned in step (1) is selected from one or more of sodium aluminate, boehmite, aluminum sulfate, and aluminum nitrate.

3. The method according to claim 1, characterized in that, The molecular sieve-containing material mentioned in step (3) is one or more of the following: waste MTO catalyst, waste molecular sieve adsorbent, waste FCC catalyst, and waste VOC adsorbent.

4. The method according to claim 1, characterized in that, The aluminum and silicon dissolution processes described in step (3) are as follows: The molecular sieve material is ground to a sample below 200 mesh, mixed with NaCO3 at a mass ratio of 1:0.5~1:5, and calcined at 550-800℃ for 60-120 min. Then, the calcined product is dissolved and filtered with a monobasic acid with a mass fraction of 10%-35% to obtain an aluminum-rich liquid. The residue is mixed with NaOH:H2O at a mass ratio of 2-100:40-60:50-400, stirred and mixed evenly, and filtered to obtain a silicon-rich liquid. Finally, the silicon-rich liquid and the aluminum-rich liquid are mixed to obtain a gel-like mother liquor. The molar ratio of each component in the gel-like mother liquor is: SiO2 / Al2O3=0.5~6.0:1, Na2O / SiO2=0.5~6.0:1, H2O / SiO2=10~100:

1.

5. The method according to claim 1, characterized in that, The amount of crystallized product added in step (4) is 5wt%-20wt% of the gel mother liquor.

6. The method according to claim 1, characterized in that, The aging conditions described in step (4) are: aging temperature of 20~100℃, aging time of 0.1~24h, and the aging process is carried out under stirring conditions.

7. The method according to claim 1, characterized in that, The hydrothermal crystallization conditions described in step (4) are: crystallization temperature of 60-105℃ and crystallization time of 0.1-36h.

8. An organic oxide adsorbent prepared by the method according to any one of claims 1 to 7, characterized in that, The core-shell structured 13X molecular sieve has the following properties: a silica-to-alumina ratio of 2.2–2.9 and a pore volume of 0.3 cm³. 3 / g~0.5 cm 3 / g, specific surface area 700m² 2 / g~950 m 2 / g.

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