Porous Cudelta+ / ZnO / Al2O3 catalyst based on sol template confinement anchoring as well as preparation method and application of porous Cudelta+ / ZnO / Al2O3 catalyst

Abstract

The invention relates to the technical field of environmental catalytic materials and advanced oxidation water treatment, in particular to a porous Cu < delta + > / ZnO / Al2O3 catalyst for efficiently activating persulfate to degrade organic pollutants as well as a preparation method and application of the porous Cu < delta + > / ZnO / Al2O3 catalyst. The preparation method comprises the following steps: dissolving a copper salt and a zinc salt in a solvent to obtain a mixed solution; adding the mixed solution into boehmite sol for aging to obtain composite sol; the composite sol is subjected to standing and drying, and xerogel is obtained; and roasting the dry gel to obtain the porous Cu < delta + > / ZnO / Al2O3 catalyst. The catalyst disclosed by the invention shows excellent catalytic activity when peroxymonosulfate is activated to degrade various organic pollutants.

Description

Technical Field

[0001] This invention relates to the field of environmental catalytic materials and advanced oxidation water treatment technology, and in particular to a porous Cu for efficiently activating persulfate to degrade organic pollutants. δ+ / ZnO / Al2O3 catalyst, its preparation method and application. Background Technology

[0002] Persulfate advanced oxidation technology is an effective means of treating recalcitrant organic wastewater, and its core lies in the development of efficient and stable heterogeneous catalysts. δ+ / ZnO / Al2O3 (CZA) catalysts are widely used in the chemical industry due to their excellent hydrogenation catalytic performance, but their application in PMS activation is still in the exploratory stage.

[0003] Currently, the preparation of this catalyst mainly employs a co-precipitation method. This method results in a pore structure primarily composed of disordered mesopores formed by particle stacking, lacking interconnectivity. This hinders the diffusion of persulfate molecules and organic contaminants within the catalyst, limiting mass transfer and preventing the full utilization of some internal active sites, thus restricting the overall reaction rate. Furthermore, the co-precipitation process is dynamically influenced by multiple factors such as ion concentration, pH, and temperature, making it difficult to precisely control the nanoscale spatial distribution of active sites and the fine structure of the support pores. Therefore, developing a novel preparation method capable of constructing robust interfaces and efficient mass transfer channels from the source is crucial for improving the Cu... δ+ The key to the persulfate activation performance of / ZnO / Al2O3 catalysts. Summary of the Invention

[0004] This invention aims to overcome the limitations of existing co-precipitation methods for preparing Cu δ+ To address the shortcomings of ZnO / Al2O3 catalysts, such as unstable active sites, low mass transfer efficiency, and difficulty in structural control, a novel synthetic method is proposed. This method employs a unique strategy of "first constructing a structural template, then assembling it in situ within a confined space" to prepare a novel catalyst with porous structure and strongly anchored active sites, significantly improving its catalytic efficiency, stability, and mass transfer capacity in the degradation of organic pollutants using activated PMS.

[0005] To achieve the above objectives, the present invention provides the following solution: One of the technical solutions of this invention is a porous Cu δ+ The preparation method of / ZnO / Al2O3 catalyst includes the following steps: Copper and zinc salts are dissolved in a solvent to obtain a mixed solution; The mixed solution was added to boehmite sol and aged to obtain a composite sol; The composite sol was allowed to stand and then dried to obtain a dry gel; The dry gel was calcined to obtain the porous Cu. δ+ / ZnO / Al2O3 catalyst.

[0006] The second technical solution of the present invention is a porous Cu obtained by the above-described preparation method. δ+ / ZnO / Al2O3 catalyst.

[0007] The third technical solution of the present invention is the aforementioned porous Cu. δ+ Application of / ZnO / Al2O3 catalyst in activating persulfate to degrade organic pollutants.

[0008] Compared with the prior art, the present invention has the following beneficial effects: (1) Fundamental innovation in methodology: A novel synthetic route of "sol template confinement and anchoring" was proposed, which is different from the traditional coprecipitation method in principle and realizes the active design and precise control of the catalyst nanostructure.

[0009] (2) Uniqueness of product structure: This method successfully constructs a unique structure integrating "strong interface coupling" and "multi-level channels". The strong anchoring effect of active sites fundamentally improves stability; the interconnected multi-level channels greatly optimize mass transfer efficiency.

[0010] (3) Excellent catalytic performance: Thanks to the above-mentioned unique structure, the catalyst of the present invention exhibits excellent catalytic activity when activating persulfate to degrade various organic pollutants.

[0011] (4) Universality and scalability of the process: The synthesis strategy has moderate equipment requirements and strong process controllability, providing a new general idea for the design and development of other high-performance multi-component metal oxide catalysts. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a process flow diagram of the preparation method of the present invention.

[0014] Figure 2 The images show the XRD patterns of the catalysts obtained in Examples 1-4.

[0015] Figure 3 Comparison of nitrogen adsorption-desorption curves and pore size distributions of the catalysts prepared in Examples 1-9 and Comparative Example 1.

[0016] Figure 4 Scanning electron microscope (SEM) images, elemental distribution images, and atomic percentage images of the catalyst prepared in Example 1.

[0017] Figure 5 Comparison of the kinetic performance of the catalysts prepared in Examples 1-10 for activating PMS to degrade Rh B under the same conditions. Detailed Implementation

[0018] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0019] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0020] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0021] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0022] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0023] This invention utilizes alumina sol templates to confine and anchor Cu and Zn species, constructing porous Cu... δ+ / ZnO / Al2O3 catalyst. Existing methods for preparing alumina sols (including methods similar to CN116102040A) primarily aim to obtain the sol itself, focusing on optimizing its stability, rheological properties, or its use in preparing pure alumina materials. These technologies concentrate on the properties of the sol as a "final product" or "intermediate chemical." However, this invention does not aim to obtain a sol, but rather creatively utilizes a uniform and stable boehmite sol as a precisely tunable three-dimensional nanostructure template and reactor. The application endpoint of this invention is to solve the structural construction challenges of high-performance catalysts. Specifically, it leverages the network confinement effect of the sol to guide the in-situ anchoring and assembly of active precursors at the molecular scale, thereby directionally constructing structures with strong metal-support interactions and porous composite catalytic materials. Therefore, existing sol technologies provide a method for preparing chemical raw materials, while this invention provides a novel strategy for designing and synthesizing specific functional materials. The two differ fundamentally in their application objectives, technological starting points, and final products.

[0024] This invention creatively proposes the "sol-template confined anchoring method," the core of which is to abandon the traditional random ion coprecipitation path and adopt a precisely controllable "template-guided-molecular anchoring" reverse synthesis strategy.

[0025] The first aspect of the present invention provides a porous Cu δ+ The preparation method of / ZnO / Al2O3 catalyst includes the following steps: Copper and zinc salts are dissolved in a solvent to obtain a mixed solution; The mixed solution was added to boehmite sol and aged to obtain a composite sol; The composite sol was allowed to stand and then dried to obtain a dry gel; The dry gel was calcined to obtain the porous Cu. δ+ / ZnO / Al2O3 catalyst.

[0026] In a preferred embodiment of the present invention, the copper salt is Cu(NO3)2·3H2O; the zinc salt is Zn(NO3)2·6H2O; the solvent is a mixture of an organic ligand and water in a volume ratio of 2~6:1, more preferably (3~5):1; the organic ligand is at least one of ethylene glycol, glycerol or polyethylene glycol.

[0027] In this invention, the volume ratio of organic ligand to water is limited to 2-6:1. Too much organic phase leads to excessively high system viscosity, which is not conducive to subsequent dropwise addition and uniform mixing, and is also uneconomical. If there is too little water, nitrates cannot be completely dissolved; if there is too much water, the concentration of organic ligand is insufficient, causing premature hydrolysis and precipitation of metal ions, thus failing to achieve "confined anchoring".

[0028] In this invention, the role of the organic ligand is to form soluble complexes with copper and zinc ions, inhibit their rapid hydrolysis, and promote their uniform dispersion and anchoring in the boehmite sol network.

[0029] In a preferred embodiment of the present invention, the boehmite sol is prepared by depolymerizing an aluminum source under acid catalysis. Depolymerizing the aluminum source under acid catalysis forms a uniform, stable, and positively charged boehmite sol, which serves as a rigid template with a three-dimensional nanonetwork structure.

[0030] The acid is nitric acid; the amount of acid added is expressed as H+. + The molar ratio of aluminum in the aluminum source to aluminum is calculated to be 0.06~0.12.

[0031] In a preferred embodiment of the present invention, the aluminum source is boehmite; the molar ratio of the aluminum source to the copper salt and zinc salt is (1~8):(1~6):1~3.

[0032] In a preferred embodiment of the present invention, the mixed solution is added to the boehmite sol by adding the mixed solution dropwise to the boehmite sol at a rate of 0.5 to 5 mL / min under continuous stirring and at a temperature of 50 to 70°C; optionally, the temperature is 50°C, 60°C, 70°C or any value between the two aforementioned values.

[0033] In a preferred embodiment of the present invention, the aging temperature is 50~70℃ and the aging time is 2~6 hours; optionally, the aging temperature is 50℃, 60℃, 70℃ or any value between the two aforementioned values; the aging time is 2 hours, 3 hours, 4 hours, 5 hours, 6 hours or any value between the two aforementioned values.

[0034] In a preferred embodiment of the present invention, the settling temperature is room temperature and the settling time is 72 hours; In a preferred embodiment of the present invention, the drying process specifically involves: first drying at 30-50°C for 12-28 hours, and then drying at 70-90°C for 24-50 hours; the drying method is slow evaporation drying or supercritical drying. In a preferred embodiment of the present invention, the roasting is a programmed roasting, specifically: first, the temperature is raised to 250-350°C at a rate of 0.5-5°C / min and held for 2-4 hours, then the temperature is raised to 350-450°C and held for 3-5 hours.

[0035] In a preferred embodiment of the present invention, after the calcination is completed, a reduction treatment step is further included in a reducing atmosphere; the reducing atmosphere is 5% H2 / Ar; the temperature of the reduction treatment is 200~350℃, and the time of the reduction treatment is 0.1~3 hours; optionally, the temperature of the reduction treatment is 200℃, 250℃, 300℃, 350℃ or any value between the two aforementioned values; the time of the reduction treatment is 0.1 hours, 0.5 hours, 1 hour, 2 hours, 3 hours or any value between the two aforementioned values.

[0036] In a preferred embodiment of the present invention, the boehmite sol further includes a pore structure guiding agent; the pore structure guiding agent is preferably at least one of polyethylene glycol (molecular weight 400~2000), polyvinylpyrrolidone, or polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer (P123 or F127).

[0037] A second aspect of the present invention provides a porous Cu obtained by the preparation method described above. δ+ / ZnO / Al2O3 catalyst.

[0038] The catalyst has a hierarchical pore structure including micropores and mesopores, with a specific surface area of ​​150 m². 2 / g or more, pore volume greater than 0.3cm 3 / g.

[0039] The third aspect of the present invention provides the above-described porous Cu δ+ Application of / ZnO / Al2O3 catalyst in activating persulfate to degrade organic pollutants. The persulfate includes potassium persulfate, sodium persulfate, etc.

[0040] Unless otherwise specified, the technical solutions described in this invention are all conventional solutions in the field, and the reagents or raw materials used are all purchased from commercial channels or are publicly available unless otherwise specified.

[0041] The pseudoboehmite used in the embodiments of this invention was purchased from Shanghai Maclean Biochemical Technology Co., Ltd., with the chemical formula AlOOH·nH2O (n = 0.08~0.62), superior grade reagent, 1 kg.

[0042] The performance testing methods involved in this embodiment of the invention are as follows: A 20 mg / L Rhodamine B (Rh B) solution (using ultrapure water as the solvent), 0.5 g / L catalyst, and 2 mM PMS were mixed and reacted at 35 °C and pH 6. The Rh B concentration was monitored by high-performance liquid chromatography (HPLC) under the following conditions: mobile phase: methanol and water at a volume ratio of 75:25; detection wavelength: λ = 554 nm.

[0043] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0044] Comparative Example 1: Synthesis of typical industrial catalyst CZA-400 by coprecipitation method Step 1, Solution preparation: Weigh 0.453g Cu(NO3)2·3H2O, 0.558g Zn(NO3)2·6H2O, and 5.63g Al(NO3)2·9H2O and dissolve them in 20 mL of deionized water. Stir magnetically until completely clear. Weigh 3.3g Na2CO3 and dissolve it in 30 mL of deionized water.

[0045] Step 2, Co-precipitation: Add 10 mL of deionized water as the base solution to a 100 mL PTFE container, preheat to 70°C, and start stirring (300 rpm). Transfer the metal salt solution and Na₂CO₃ solution into the syringes of two separate constant flow pumps. Control the dropping rate of both solutions to 2.0 mL / min to allow for slow precipitate formation. Maintain the pH at 7.0 by finely adjusting the dropping rate ratio. After the addition is complete (approximately 100 min), continue aging at 70°C and 300 rpm for 2 hours.

[0046] Step 3, Washing and Filtration: Cool the precipitated slurry to room temperature and transfer it to a vacuum filtration device. Wash the precipitate with plenty of deionized water and dry it to obtain a filter cake.

[0047] Step 4, Drying and Calcination: Place the filter cake in a petri dish and dry it in a 110°C forced-air drying oven for 12 hours.

[0048] The dried block was gently ground into powder (avoiding over-grinding). The powder was spread evenly in a porcelain boat and placed in a muffle furnace. The temperature was increased to 400°C at 2°C / min and maintained for 4 hours (at air). After natural cooling to room temperature, CZA-400 catalyst was obtained, which was a black powder (mainly containing CuO, ZnO, and Al2O3).

[0049] Example 1 Step 1, Preparation of alumina sol: Disperse 5.0g in 70mL of deionized water, slowly add 4.0mL of concentrated nitric acid while stirring, and stir vigorously in a 60℃ water bath for 2 hours to obtain a transparent boehmite sol.

[0050] Step 2: Preparation and introduction of the active precursor: Dissolve 2.41 g Cu(NO3)2·3H2O and 2.97 g Zn(NO3)2·6H2O in a mixed solution of 40 mL ethylene glycol and 10 mL water. While stirring at 60 °C and 400 rpm, slowly add the above solution dropwise to the sol from Step 1 at a rate of 1.5 mL / min. After the addition is complete, age at 60 °C for 4 hours to obtain a homogeneous composite sol.

[0051] Step 3, gelation and drying: The composite sol was allowed to stand at room temperature for 72 hours to form a gel, then dried at 40°C for 24 hours, and then dried at 80°C for 48 hours to obtain a dry gel (gel precursor).

[0052] Step 4, programmed calcination: The dry gel was ground and placed in a muffle furnace, heated to 300℃ at 1℃ / min and held for 3 hours, then heated to 400℃ at 2℃ / min and held for 4 hours. After natural cooling, the final catalyst was obtained, denoted as CZA-SG-400.

[0053] The calcination temperature in step 4 of Example 1 was adjusted from 400℃ to 500℃ and 600℃ respectively. The remaining steps and parameters were the same as in Example 1. The catalysts obtained were labeled as CZA-SG-500 and CZA-SG-600 respectively.

[0054] Example 2 The only difference from Example 1 is that the addition of 2.97g Zn(NO3)2·6H2O in step 2 is omitted; the other steps and parameters are the same as in Example 1; the catalyst obtained is denoted as CA-SG-400.

[0055] Example 3 The only difference from Example 1 is that the addition of 2.41g Cu(NO3)2·3H2O in step 2 is omitted; the remaining steps and parameters are the same as in Example 1; the catalyst obtained is denoted as ZA-SG-400.

[0056] Example 4 Step 1, Preparation of alumina sol: Disperse 5.0g of boehmite in 70mL of deionized water, slowly add 4.0mL of concentrated nitric acid while stirring, and stir vigorously in a 60℃ water bath for 2 hours to obtain a transparent boehmite sol.

[0057] Step 2, gelation and drying: The sol was allowed to stand at room temperature for 72 hours to form a gel, then dried at 40°C for 24 hours, and then dried at 80°C for 48 hours to obtain a dry gel.

[0058] Step 3, programmed calcination: The dry gel was ground and placed in a muffle furnace, heated to 300°C at 1°C / min and held for 3 hours, then heated to 400°C at 2°C / min and held for 4 hours. After natural cooling, the final catalyst was obtained, denoted as A-SG-400 (i.e., the only difference from Example 1 is that step 2 is omitted).

[0059] Example 5 Step 1, Preparation of alumina sol: Disperse 5.0g of boehmite in 70mL of deionized water, slowly add 4.0mL of concentrated nitric acid while stirring, and stir vigorously in a 60℃ water bath for 2 hours to obtain a transparent boehmite sol. Then add 0.54g of polyethylene glycol 400 (PEG400) and continue stirring until completely dissolved.

[0060] Step 2: Preparation and introduction of the active precursor: Dissolve 2.41 g Cu(NO3)2·3H2O and 2.97 g Zn(NO3)2·6H2O in a mixed solution of 40 mL ethylene glycol and 10 mL water. While stirring at 60 °C and 400 rpm, slowly add the above solution dropwise to the sol from Step 1 at a rate of 1.5 mL / min. After the addition is complete, age at 60 °C for 4 hours to obtain a homogeneous composite sol.

[0061] Step 3, gelation and drying: The composite sol was allowed to stand at room temperature for 72 hours to form a gel, then dried at 40°C for 24 hours, and then dried at 80°C for 48 hours to obtain a dry gel.

[0062] Step 4, programmed calcination and reduction: The dry gel was ground and placed in a muffle furnace, heated to 300°C at 1°C / min and held for 3 hours, then heated to 400°C at 2°C / min and held for 4 hours. After natural cooling, the final catalyst was obtained, denoted as CZA-SG-PEG400-400 (i.e., the only difference from Example 1 is that 0.54g of PEG400 was added in Step 1).

[0063] Example 6 Step 1, Preparation of alumina sol: Disperse 5.0g of boehmite in 70mL of deionized water, slowly add 4.0mL of concentrated nitric acid while stirring, and stir vigorously in a 60℃ water bath for 2 hours to obtain a transparent boehmite sol. Then add 0.54g of polyethylene glycol 1000 (PEG1000) and continue stirring until completely dissolved.

[0064] Step 2: Preparation and introduction of the active precursor: Dissolve 2.41 g Cu(NO3)2·3H2O and 2.97 g Zn(NO3)2·6H2O in a mixed solution of 40 mL ethylene glycol and 10 mL water. While stirring at 60 °C and 400 rpm, slowly add the above solution dropwise to the sol from Step 1 at a rate of 1.5 mL / min. After the addition is complete, age at 60 °C for 4 hours to obtain a homogeneous composite sol.

[0065] Step 3, gelation and drying: The composite sol was allowed to stand at room temperature for 72 hours to form a gel, then dried at 40°C for 24 hours, and then dried at 80°C for 48 hours to obtain a dry gel.

[0066] Step 4, programmed calcination and reduction: The dry gel was ground and placed in a muffle furnace, heated to 300°C at 1°C / min and held for 3 hours, then heated to 400°C at 2°C / min and held for 4 hours. After natural cooling, the final catalyst was obtained, denoted as CZA-SG-PEG1000-400 (i.e., the only difference from Example 1 is that 0.54g of PEG1000 was added in Step 1).

[0067] Example 7 Step 1, Preparation of alumina sol: Disperse 5.0g of boehmite in 70mL of deionized water, slowly add 4.0mL of concentrated nitric acid while stirring, and stir vigorously in a 60℃ water bath for 2 hours to obtain a transparent boehmite sol. Then add 0.54g of polyethylene glycol 2000 (PEG2000) and continue stirring until completely dissolved.

[0068] Step 2: Preparation and introduction of the active precursor: Dissolve 2.41 g Cu(NO3)2·3H2O and 2.97 g Zn(NO3)2·6H2O in a mixed solution of 40 mL ethylene glycol and 10 mL water. While stirring at 60 °C and 400 rpm, slowly add the above solution dropwise to the sol from Step 1 at a rate of 1.5 mL / min. After the addition is complete, age at 60 °C for 4 hours to obtain a homogeneous composite sol.

[0069] Step 3, gelation and drying: The composite sol was allowed to stand at room temperature for 72 hours to form a gel, then dried at 40°C for 24 hours, and then dried at 80°C for 48 hours to obtain a dry gel.

[0070] Step 4, programmed calcination and reduction: The dry gel was ground and placed in a muffle furnace, heated to 300°C at 1°C / min and held for 3 hours, then heated to 400°C at 2°C / min and held for 4 hours. After natural cooling, the final catalyst was obtained, denoted as CZA-SG-PEG2000-400 (i.e., the only difference from Example 1 is that 0.54g of PEG2000 was added in Step 1).

[0071] Example 8 Step 1, Preparation of alumina sol: Disperse 5.0g of boehmite in 70mL of deionized water, slowly add 4.0mL of concentrated nitric acid while stirring, and stir vigorously in a 60℃ water bath for 2 hours to obtain a transparent boehmite sol. Then add 1.0g of P123 and continue stirring until completely dissolved.

[0072] Step 2: Preparation and introduction of the active precursor: Dissolve 2.41 g Cu(NO3)2·3H2O and 2.97 g Zn(NO3)2·6H2O in a mixed solution of 40 mL ethylene glycol and 10 mL water. While stirring at 60 °C and 400 rpm, slowly add the above solution dropwise to the sol from Step 1 at a rate of 1.5 mL / min. After the addition is complete, age at 60 °C for 4 hours to obtain a homogeneous composite sol.

[0073] Step 3, gelation and drying: The composite sol was allowed to stand at room temperature for 72 hours to form a gel, then dried at 40°C for 24 hours, and then dried at 80°C for 48 hours to obtain a dry gel.

[0074] Step 4, programmed calcination and reduction: The dry gel was ground and placed in a muffle furnace, heated to 300°C at 1°C / min and held for 3 hours, then heated to 400°C at 2°C / min and held for 4 hours. After natural cooling, the final catalyst was obtained, denoted as CZA-SG-P123-400 (i.e., the only difference from Example 1 is that 1.0 g of P123 was added in step 1).

[0075] Example 9 Step 1, Preparation of alumina sol: Disperse 5.0g of boehmite in 70mL of deionized water, slowly add 4.0mL of concentrated nitric acid while stirring, and stir vigorously in a 60℃ water bath for 2 hours to obtain a transparent boehmite sol. Then add 1.2g of F127 and continue stirring until completely dissolved.

[0076] Step 2: Preparation and introduction of the active precursor: Dissolve 2.41 g Cu(NO3)2·3H2O and 2.97 g Zn(NO3)2·6H2O in a mixed solution of 40 mL ethylene glycol and 10 mL water. While stirring at 60 °C and 400 rpm, slowly add the above solution dropwise to the sol from Step 1 at a rate of 1.5 mL / min. After the addition is complete, age at 60 °C for 4 hours to obtain a homogeneous composite sol.

[0077] Step 3, gelation and drying: The composite sol was allowed to stand at room temperature for 72 hours to form a gel, then dried at 40°C for 24 hours, and then dried at 80°C for 48 hours to obtain a dry gel.

[0078] Step 4, programmed calcination and reduction: The dry gel was ground and placed in a muffle furnace, heated to 300°C at 1°C / min and held for 3 hours, then heated to 400°C at 2°C / min and held for 4 hours. After natural cooling, the final catalyst was obtained, denoted as CZA-SG-F127-400 (i.e., the only difference from Example 1 is that 1.2g of F127 was added in step 1).

[0079] Example 10 Step 1, Preparation of alumina sol: Disperse 5.0g of boehmite in 70mL of deionized water, slowly add 4.0mL of concentrated nitric acid while stirring, and stir vigorously in a 60℃ water bath for 2 hours to obtain a transparent boehmite sol.

[0080] Step 2: Preparation and introduction of the active precursor: Dissolve 2.41 g Cu(NO3)2·3H2O and 2.97 g Zn(NO3)2·6H2O in a mixed solution of 40 mL ethylene glycol and 10 mL water. While stirring at 60 °C and 400 rpm, slowly add the above solution dropwise to the sol from Step 1 at a rate of 1.5 mL / min. After the addition is complete, age at 60 °C for 4 hours to obtain a homogeneous composite sol.

[0081] Step 3, gelation and drying: The composite sol was allowed to stand at room temperature for 72 hours to form a gel, then dried at 40°C for 24 hours, and then dried at 80°C for 48 hours to obtain a dry gel.

[0082] Step 4, programmed calcination and reduction: The dry gel was ground and placed in a muffle furnace, heated to 300°C at 1°C / min and held for 3 hours, then heated to 400°C at 2°C / min and held for 4 hours. After natural cooling, it was reduced in a tube furnace with 5% H2 / Ar at 300°C for 0.5 hours to obtain the final catalyst, denoted as CZA-SG-H2-300 (i.e., the only difference from Example 1 is that the step of "reduction in a tube furnace with 5% H2 / Ar at 300°C for 0.5 hours" was added after calcination in Step 4).

[0083] Table 1. Structural comparison of the catalysts synthesized in Examples 1-9 of this invention with the typical catalyst CZA synthesized by co-precipitation method in Comparative Example 1.

[0084] Table 1. Data Comparison: Cu synthesized based on the method of this invention. δ+ The / ZnO / Al2O3 catalyst has a higher specific surface area, and the pore size can be controlled by introducing a template agent as needed, which is something that cannot be achieved by the traditional coprecipitation method.

[0085] Figure 2 These are XRD patterns of the catalysts obtained in Examples 1-4. Figure 2 It can be seen that the prepared aluminum sol is transformed into a γ-Al2O3 support after programmed calcination, and the loaded Cu and Zn components are transformed into their corresponding oxides (CuO and ZnO), respectively, with no other characteristic peaks of impurities.

[0086] Figure 3 Comparison of nitrogen adsorption-desorption curves and pore size distributions of the catalysts prepared in Examples 1-9 and Comparative Example 1. Figure 4It can be seen that the catalyst prepared in Comparative Example 1 is a stacked disordered mesopore with a significantly smaller specific surface area (see Table 1), while the catalysts prepared in Examples 1-9 form an ordered pore structure with a high specific surface area and adjustable pore size.

[0087] Figure 4 Scanning electron microscope (SEM) images, elemental distribution images, and atomic percentage images of the catalyst prepared in Example 1. Figure 4 This demonstrates that the active components are uniformly dispersed on the carrier according to the dosage ratio.

[0088] Performance testing 1. Add 50 ml of a 20 mg / L Rhodamine B (Rh B) solution (water) to a 50 ml Erlenmeyer flask, followed by 1 ml of a 100 mM PMS solution (water). Under stirring, at certain time intervals, take 1.5 ml of the solution and filter it through a filter for liquid chromatography analysis. The results show that for the PMS-only system, the removal rate of Rh B within 30 minutes is less than 10%, indicating that the kinetics of PMS's own decomposition and degradation of pollutants are very slow (e.g., Figure 5 (As shown).

[0089] 2. Add 50 ml of 20 mg / L Rh B solution to a 50 ml Erlenmeyer flask, followed by 25 mg of powdered catalyst CZA-SG-400. After stirring and adsorption for 30 minutes, add 1 ml of 100 mM PMS solution (water as solvent). At regular intervals, take 1.5 ml samples, filter through a filter, and use for liquid chromatography analysis. The results show that the CZA-SG-400 synthesized in Example 1 can completely remove Rh B within 8 minutes (e.g., ...). Figure 5 (As shown).

[0090] Under the above reaction conditions, when the catalyst was replaced with the catalysts prepared in Examples 2-10, the time required for complete removal of RhB was 10, 27, 30, 7, 8, 5, 2, 10, and 8 min, respectively. This indicates that Examples 2-10 can efficiently activate PMS to degrade pollutants (such as...). Figure 5 (As shown).

[0091] Under the above reaction conditions, when the catalyst was replaced with CZA-SG-500 and CZA-SG-600 catalysts, respectively, the time for complete removal of RhB was 13 and 14 min, respectively. This indicates that both CZA-SG-500 and CZA-SG-600 catalysts can efficiently activate PMS to degrade pollutants (such as...). Figure 5 (As shown).

[0092] Under the above reaction conditions, the catalyst was replaced with the catalyst prepared in Comparative Example 1, and the results showed that the time for complete removal of Rh B was 65 min.

[0093] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A porous Cu δ+ The method for preparing the / ZnO / Al2O3 catalyst is characterized by, Includes the following steps: Copper and zinc salts are dissolved in a solvent to obtain a mixed solution; The mixed solution was added to boehmite sol and aged to obtain a composite sol; The composite sol was allowed to stand and then dried to obtain a dry gel; The dry gel was calcined to obtain the porous Cu. δ+ / ZnO / Al2O3 catalyst.

2. The preparation method according to claim 1, characterized in that, The copper salt is Cu(NO3)2·3H2O; the zinc salt is Zn(NO3)2·6H2O; the solvent is a mixture of an organic ligand and water in a volume ratio of 2 to 6:1; the organic ligand is at least one of ethylene glycol, glycerol, or polyethylene glycol.

3. The preparation method according to claim 1, characterized in that, The boehmite sol was prepared by depolymerizing an aluminum source under acid catalysis.

4. The preparation method according to claim 3, characterized in that, The aluminum source is boehmite; the molar ratio of the aluminum source to the copper salt and zinc salt is (1~8):(1~6):1~3.

5. The preparation method according to claim 1, characterized in that, The mixed solution is added to the boehmite sol by adding the mixed solution dropwise to the boehmite sol at a rate of 0.5-5 mL / min under continuous stirring and at a temperature of 50-70°C.

6. The preparation method according to claim 1, characterized in that, The aging temperature is 50~70℃, and the aging time is 2~6 hours; the settling temperature is room temperature, and the settling time is 72 hours; the drying process specifically involves drying at 30~50℃ for 12~28 hours, and then drying at 70~90℃ for 24~50 hours; the roasting process specifically involves heating to 250~350℃ at a rate of 0.5~5℃ / min and holding for 2~4 hours, followed by heating to 350~450℃ and holding for 3~5 hours.

7. The preparation method according to claim 1, characterized in that, After the roasting is completed, a reduction treatment step is also included, which is carried out in a reducing atmosphere of 5% H2 / Ar; the temperature of the reduction treatment is 200~350℃ and the time of the reduction treatment is 0.1~3 hours.

8. The preparation method according to claim 1, characterized in that, The boehmite sol also includes a pore structure guiding agent; the pore structure guiding agent is preferably at least one of polyethylene glycol, polyvinylpyrrolidone, or polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer.

9. A porous Cu obtained by the preparation method according to any one of claims 1 to 8 δ+ / ZnO / Al2O3 catalyst.

10. The porous Cu as described in claim 9 δ+ Application of / ZnO / Al2O3 catalyst in activating persulfate to degrade organic pollutants.

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