Preparation method and application of copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst

Abstract

The application belongs to the technical field of water treatment and environmental catalytic materials, and particularly relates to a preparation method and application of a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst. Through a time sequence control organic-inorganic synergistic self-assembly-selective template removal method, the condensation rate of resorcinol and formaldehyde and the SiO2 generation rate are simultaneously controlled in an alkaline environment, the resin is carbonized into a carbon skeleton, the hollow shell and peripheral channel structure are constructed by etching SiO2, copper is complexed by 1,10-phenanthroline and limited in the carbon skeleton by high-temperature calcination, which not only exposes the copper active site, but also limits the loss of copper species. In the same particle, efficient mass transfer, limited reaction, site stabilization and reaction path control are simultaneously achieved, which can quickly activate hydrogen peroxide into hydroxyl radicals, and quickly remove various pollutants in 1 minute. The application provides a solution to the contradiction between activity and stability faced by heterogeneous water treatment advanced oxidation technology, and has a good application prospect.

Description

Technical Field

[0001] This invention belongs to the field of water treatment and environmental catalytic materials technology, specifically relating to the preparation method and application of a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst. Background Technology

[0002] Advanced oxidation processes (AOPs) are considered an important direction for the development of advanced water treatment because they can generate highly oxidizing active species such as hydroxyl radicals (•OH) in situ.

[0003] Among numerous AOPs systems, the Fenton-like reaction system based on hydrogen peroxide (H2O2) activation has advantages such as mild reaction conditions, strong oxidation capacity, and wide applicability to a wide range of water qualities. However, traditional homogeneous Fenton systems suffer from problems such as large amounts of iron sludge formation, narrow pH applicability, and secondary pollution from metal ions, which limit their engineering applications.

[0004] Heterogeneous copper-based catalysts have attracted attention due to their efficient activation of H₂O₂ over a wide pH range. However, existing copper-based catalytic materials generally suffer from the following problems:

[0005] (1) Copper species are prone to leaching during the reaction, which leads to a decrease in catalyst stability and the risk of secondary pollution;

[0006] (2) Solid or ordinary mesoporous structures cannot simultaneously achieve both active site exposure and mass transfer efficiency;

[0007] (3) The active site lacks effective confinement, the reaction pathway is uncontrollable, and it is difficult to balance activity and stability.

[0008] Therefore, there is an urgent need to develop a novel heterogeneous copper-based water treatment catalyst with controllable structure, stable copper species, and high mass transfer efficiency to achieve efficient activation of H2O2 and rapid removal of emerging pollutants in water. Summary of the Invention

[0009] To address the contradiction between high activity and stability of catalysts in the treatment of new water pollution in existing technologies, this invention provides a method for preparing and applying a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] The first aspect of this invention provides a method for preparing a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst, the preparation method comprising the following steps:

[0012] (1) Add ammonia water to a mixed solution of ethanol and deionized water, stir in a water bath, add formaldehyde solution, and stir to obtain solution A;

[0013] (2) Add resorcinol to solution A, stir for a certain time, then add tetrapropoxysilane to obtain solution B;

[0014] (3) Stir in water bath, centrifuge, wash, and dry to obtain a yellowish-brown solid 1;

[0015] (4) After grinding solid 1, it is calcined in an inert gas to obtain black solid 2;

[0016] (5) Add solid 2 to sodium hydroxide solution, heat and stir, centrifuge, wash with water and dry to obtain black hollow porous nanospheres (HPCS).

[0017] (6) HPCS, copper chloride monohydrate and 1,10-o-phenanthroline were dispersed in a mixed solution of deionized water and ethanol, heated and stirred, filtered, washed and dried to obtain solid 3;

[0018] (7) Solid 3 was calcined in an inert gas to obtain copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst (Cu-HPCS).

[0019] Further, in step (1), the volume ratio of ammonia, formaldehyde solution, ethanol and deionized water is 1~10:0.5~5:65:15.

[0020] Further, in step (2), the ratio of resorcinol to solution A is 0.1~2g:81.5~95mL, and the volume ratio of tetrapropoxysilane to solution A is 1~10:81.5~95.

[0021] Furthermore, the stirring time in step (2) is 0~90 min, and the water bath stirring time in step (3) is 12~48 h.

[0022] Furthermore, in steps (4) and (7), the calcination temperature is 500~1000 ℃.

[0023] Furthermore, in step (5), the concentration of the sodium hydroxide solution is 1~5 mol / L.

[0024] Further, in step (6), the mass ratio of HPCS, copper chloride monohydrate and 1,10-o-phenanthroline is 10~200:1~20:5~20.

[0025] The second aspect of this invention provides a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst prepared by the above-described preparation method. The catalyst is a black solid powder with extremely low density and a microstructure consisting of copper-doped hollow nanospheres with a shell rich in nanopores. The internal hollow ratio can be controlled by adjusting the interval between the addition of resorcinol and tetrapropoxysilane. The shell has abundant nanopores and an extremely high specific surface area. Furthermore, metallic copper is stably anchored within the nanopore structure through the combined effects of 1,10-o-phenanthroline complexation, high-temperature calcination, and nano-confinement, providing an ideal environment for efficient mass transfer and rapid confined reactions. This avoids the activity reduction and secondary pollution problems caused by the dissolution of metallic copper during the catalytic reaction. Ultimately, Cu-HPCS achieves rapid activation of H2O2, and a large amount of •OH in the confined space rapidly removes various pollutants. It exhibits excellent stability during two weeks of continuous flow operation, demonstrating promising application prospects.

[0026] A third aspect of the present invention provides an application of the above-mentioned copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst in the degradation of pollutants in water, wherein the pollutants are at least one of bisphenol A, tetracycline, ciprofloxacin, sulfamethoxazole, and 2,4-dichlorophenol.

[0027] Furthermore, the method of application is as follows: copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst is dispersed in a solution containing the pollutants, and then 20 mol / L hydrogen peroxide is added.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] This invention provides a method for preparing and applying a copper-doped hollow-shell porous nanosphere advanced oxidation water treatment catalyst. The hollow-shell structure and the outer shell rich in nanopores endow the catalyst with a large specific surface area, facilitating the full exposure of active sites. The hollow-shell structure and nanopores enable high mass transfer properties of reactant molecules in water. Furthermore, the abundant nanopore structure provides an ideal site for efficient confined reactions, resulting in extremely high reactivity and exhibiting extremely high degradation efficiency for various novel pollutants. The abundant nanopore structure and Cu-N coordination firmly anchor metallic copper. High mass transfer and confined reactions combine to achieve both high activity and stability. After 14 days of continuous operation in a constructed membrane continuous flow reactor, it still maintained near-complete removal of pollutants, and no leaching of metallic copper was detected. The hollow-shell structure and nanopore structure, combined with highly active copper sites, successfully overcome the activity-stability contradiction in the application of heterogeneous advanced oxidation water treatment catalysts, showing promising engineering application prospects. Specifically, this invention has the following advantages:

[0030] (1) The catalyst of the present invention has the feature of hollow structure, and the proportion of hollow structure can be controlled by controlling the time interval between the addition of catechol and tetrapropoxysilane.

[0031] (2) The abundant nanopore structure of the catalyst shell of the present invention provides an ideal site for the reaction molecules to undergo efficient confined reactions.

[0032] (3) The empty shell structure and abundant nanopores of the catalyst of the present invention bring about a huge specific surface area, which fully exposes the active site copper and promotes the efficient mass transfer of reactant molecules in water.

[0033] (4) The catalyst shell of the present invention has a rich nanoporous structure. Combined with 1,10-o-phenanthroline complexation and high-temperature calcination, it firmly anchors the metallic copper, avoiding the loss of copper and secondary pollution during the catalytic reaction, and demonstrating the stability, safety and economy of long-term operation. Attached Figure Description

[0034] Figure 1 The images shown are scanning electron microscope (SEM), transmission electron microscope (TEM), and energy dispersive X-ray spectroscopy (EDS mapping) images of Cu-HPCS prepared in Example 1 of this invention. In the images, a is the SEM image, b is the TEM image, and c is the EDS mapping image. Blue represents C, green represents N, and yellow represents Cu.

[0035] Figure 2 The X-ray diffraction (XRD) pattern of Cu-HPCS prepared in Example 1 of this invention.

[0036] Figure 3 The image shows the nitrogen adsorption-desorption isotherm of Cu-HPCS prepared in Example 1 of this invention.

[0037] Figure 4 This is a pore size distribution diagram of Cu-HPCS prepared in Example 1 of the present invention.

[0038] Figure 5 The images shown are SEM and TEM images of Cu-HPCS-20 and Cu-HPCS-80 prepared in Examples 2 and 3 of this invention, where a is the SEM image of Cu-HPCS-20, b is the TEM image of Cu-HPCS-20, c is the SEM image of Cu-HPCS-80, and d is the TEM image of Cu-HPCS-80.

[0039] Figure 6 SEM image of Cu-HPCS-O prepared in Comparative Example 1 of this invention.

[0040] Figure 7The diagram shows the activity evaluation of HPCS, Cu-HPCS prepared in Example 1, Cu-HPCS-P prepared in Comparative Example 2, and Cu-HPCS-T prepared in Comparative Example 3 in activating H2O2 to degrade BPA.

[0041] Figure 8 The electron paramagnetic resonance (EPR) spectra of HPCS and Cu-HPCS activated by H2O2 to generate •OH prepared in Example 1 of this invention are shown.

[0042] Figure 9 This is an activity evaluation diagram of Cu-HPCS activated H2O2 prepared in Example 1 of the present invention for degrading various pollutants.

[0043] Figure 10 The figures show the membrane continuous flow reaction results of the Cu-HPCS-P prepared in Comparative Example 2, the Cu-HPCS-T prepared in Comparative Example 3, and the Cu-HPCS prepared in Example 1 for removing pollutants. Detailed Implementation

[0044] The specific embodiments of the present invention will be further described below. It should be noted that these descriptions are for the purpose of aiding understanding the present invention, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0045] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods, and the experimental materials used in the following embodiments are all available through conventional commercial channels.

[0046] Example 1: Preparation and characterization of the catalyst Cu-HPCS

[0047] (1) Add 2.5 mL of ammonia (26.0%) to a mixed solution of 65 mL of ethanol and 15 mL of deionized water, stir in a 30°C water bath to mix thoroughly, then add 0.8 mL of formaldehyde solution (38.0%) and stir for 5 minutes to obtain solution A;

[0048] (2) Add 0.6 g of resorcinol quickly to solution A, and immediately add 6.0 mL of tetrapropoxysilane to obtain solution B;

[0049] (3) Solution B was stirred thoroughly in a water bath at 30 °C for 24 hours, centrifuged, washed three times with ethanol and water, and then dried in a vacuum drying oven at 60 °C for 12 hours to obtain a yellowish-brown solid 1;

[0050] (4) After grinding 1.5 g of solid 1 thoroughly, place it in a tube furnace and calcine it at 900 °C for 2 hours in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain black solid 2.

[0051] (5) 1.0 g of solid 2 was added to 100 mL of 2.0 mol / L NaOH solution and stirred continuously for 24 hours at 50 °C. After centrifugation, washing with water and drying, black HPCS was obtained.

[0052] (6) Disperse 0.5 g HPCS, 64.0 mg CuCl2•H2O and 139.0 mg 1,10-o-phenanthroline in a mixed solution of 100 mL deionized water and 700 mL ethanol, stir at 60 °C for 3 hours, filter, wash with ethanol 3 times, and dry to obtain solid 3.

[0053] (7) Place 0.2 g of solid 3 in a tube furnace and calcine it at 900 °C for 1 hour in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain Cu-HPCS.

[0054] Figure 1 Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS mapping) images of the Cu-HPCS prepared in this embodiment. The SEM image shows that Cu-HPCS are uniform nanospheres (e.g., Figure 1 As shown in (a), the TEM image shows that Cu-HPCS is hollow, with a hollow content of 0.5%, and the outer shell is filled with nanopores extending from the outside to the inside (e.g., Figure 1 As shown in b), the EDS mapping diagram shows that Cu-HPCS is mainly composed of C, with N and Cu elements evenly distributed (e.g., ...). Figure 1 As shown in cf), this indicates that the metal Cu was effectively anchored in the pore structure and may have been effectively coordinated with N, and that copper did not form obvious metal particles.

[0055] Figure 2 The X-ray diffraction (XRD) pattern of Cu-HPCS prepared in this embodiment shows that, apart from the basic carbon structure peaks, no obvious diffraction peaks of copper species were found, indicating that copper did not form obvious metal particles, which is consistent with the TEM analysis results.

[0056] Figure 3 The image shows the nitrogen adsorption-desorption isotherm of the Cu-HPCS prepared in this embodiment. The obvious hysteresis loop indicates the presence of a distinct mesoporous structure, providing an ideal space for the confined reaction, with an overall specific surface area reaching 1276 m². 2 / g allows the active sites to be fully exposed, and the confined space and high density of active sites are conducive to the efficient catalytic reaction.

[0057] Figure 4 This is a pore size distribution diagram of the Cu-HPCS catalyst prepared in this embodiment. It shows that the nanopore size of the catalyst is concentrated around 9 nm, further confirming the abundant nanopore structure of the empty shell of the Cu-HPCS catalyst.

[0058] Example 2: Preparation of Cu-HPCS-20

[0059] (1) Add 2.5 mL of ammonia (26.0%) to a mixed solution of 65 mL of ethanol and 15 mL of deionized water, stir in a 30°C water bath to mix thoroughly, then add 0.8 mL of formaldehyde solution (38.0%) and stir for 5 minutes to obtain solution A;

[0060] (2) Add 0.6 g of resorcinol to solution A quickly, stir for 20 minutes, and then add 6.0 mL of tetrapropoxysilane to obtain solution B;

[0061] (3) Solution B was stirred thoroughly in a water bath at 30 °C for 24 hours, centrifuged, washed three times with ethanol and water, and then dried in a vacuum drying oven at 60 °C for 12 hours to obtain a yellowish-brown solid 1;

[0062] (4) After grinding 1.5 g of solid 1 thoroughly, place it in a tube furnace and calcine it at 900 °C for 2 hours in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain black solid 2.

[0063] (5) Add 1.0 g of solid 2 to 100 mL of 2.0 mol / L NaOH solution, stir continuously for 24 hours at 50 °C, and obtain black HPCS-20 after centrifugation, washing with water and drying;

[0064] (6) Disperse 0.5 g HPCS-20, 64.0 mg CuCl2•H2O and 139.0 mg 1,10-o-phenanthroline in a mixed solution of 100 mL deionized water and 700 mL ethanol, stir at 60 °C for 3 hours, filter, wash with ethanol 3 times, and dry to obtain solid 3.

[0065] (7) Place 0.2 g of solid 3 in a tube furnace and calcine it at 900 °C for 1 hour in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain Cu-HPCS-20.

[0066] Example 3: Preparation of Cu-HPCS-80

[0067] (1) Add 2.5 mL of ammonia (26.0%) to a mixed solution of 65 mL of ethanol and 15 mL of deionized water, stir in a 30°C water bath to mix thoroughly, then add 0.8 mL of formaldehyde solution (38.0%) and stir for 5 minutes to obtain solution A;

[0068] (2) Add 0.6 g of resorcinol to solution A quickly, stir for 80 minutes, and then add 6.0 mL of tetrapropoxysilane to obtain solution B;

[0069] (3) Solution B was stirred thoroughly in a water bath at 30 °C for 24 hours, centrifuged, washed three times with ethanol and water, and then dried in a vacuum drying oven at 60 °C for 12 hours to obtain a yellowish-brown solid 1;

[0070] (4) After grinding 1.5 g of solid 1 thoroughly, place it in a tube furnace and calcine it at 900 °C for 2 hours in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain black solid 2.

[0071] (5) Add 1.0 g of solid 2 to 100 mL of 2.0 mol / L NaOH solution, stir continuously for 24 hours at 50 °C, and obtain black HPCS-80 after centrifugation, washing with water and drying;

[0072] (6) Disperse 0.5 g HPCS-80, 64.0 mg CuCl2•H2O and 139.0 mg 1,10-o-phenanthroline in a mixed solution of 100 mL deionized water and 700 mL ethanol, stir at 60 °C for 3 hours, filter, wash with ethanol 3 times, and dry to obtain solid 3.

[0073] (7) Place 0.2 g of solid 3 in a tube furnace and calcine it at 900 °C for 1 hour in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain Cu-HPCS-80.

[0074] Figure 5 The images show SEM and TEM images of Cu-HPCS-20 and Cu-HPCS-80, where a is the SEM image of Cu-HPCS-20, b is the TEM image of Cu-HPCS-20, c is the SEM image of Cu-HPCS-80, and d is the TEM image of Cu-HPCS-80. If tetrapropoxysilane is added 20 minutes after the addition of catechol, hollow nanospheres with a hollow diameter equal to 0.2 times the particle diameter can be obtained (e.g., ...). Figure 5 As shown in a and b); if tetrapropoxysilane is added 80 minutes after the addition of catechol, solid nanospheres with a solid content of 0.4% can be obtained (e.g., Figure 5(As shown in c and d). It can be seen that by controlling the time interval between the addition of catechol and tetrapropoxysilane, the hollow ratio can be effectively regulated, and the size of the external nanopores can also be regulated.

[0075] Comparative Example 1: Preparation of Cu-HPCS-O

[0076] (1) Add 2.5 mL of ammonia (26.0%) to a mixed solution of 65 mL of ethanol and 15 mL of deionized water, and stir in a water bath at 30°C to mix thoroughly. Then, add 0.8 mL of formaldehyde solution (38.0%) and 0.6 g of resorcinol, and stir for 5 minutes to obtain solution A.

[0077] (2) Add 6.0 mL of tetrapropoxysilane to solution A and stir thoroughly in a water bath at 30 °C for 24 hours to obtain solution B;

[0078] (3) After centrifugation and washing with ethanol and water three times, solution B was dried in a vacuum drying oven at 60 °C for 12 hours to obtain a yellowish-brown solid 1;

[0079] (4) After grinding 1.5 g of solid 1 thoroughly, place it in a tube furnace and calcine it at 900 °C for 2 hours in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain black solid 2.

[0080] (5) Add 1.0 g of solid 2 to 100 mL of 2.0 mol / L NaOH solution, stir continuously for 24 hours at 50 °C, and obtain black HPCS-O after centrifugation, washing with water and drying;

[0081] (6) Disperse 0.5 g HPCS-O, 64.0 mg CuCl2•H2O and 139.0 mg 1,10-o-phenanthroline in a mixed solution of 100 mL deionized water and 700 mL ethanol, stir at 60 °C for 3 hours, filter, wash with ethanol 3 times, and dry to obtain solid 3.

[0082] (7) Place 0.2 g of solid 3 in a tube furnace and calcine it at 900 °C for 1 hour in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain Cu-HPCS-O.

[0083] Figure 6The SEM image of Cu-HPCS-O prepared in this comparative example shows that if the order of reagent addition is changed, and formaldehyde and resorcinol are added simultaneously, the resulting spherical structure will be broken and incomplete due to solvent diffusion and reaction inhomogeneity, failing to maintain the ideal hollow porous structure. In Example 1, formaldehyde was added first, stirred for 5 minutes to allow it to disperse fully, and then resorcinol was added. This actual order of addition better maintains the integrity of the structure.

[0084] Comparative Example 2: Preparation of Cu-HPCS-P

[0085] (1) Add 2.5 mL of ammonia (26.0%) to a mixed solution of 65 mL of ethanol and 15 mL of deionized water, stir in a 30°C water bath to mix thoroughly, then add 0.8 mL of formaldehyde solution (38.0%) and stir for 5 minutes to obtain solution A;

[0086] (2) Add 0.6 g of resorcinol quickly to solution A, and immediately add 6.0 mL of tetrapropoxysilane to obtain solution B;

[0087] (3) Solution B was stirred thoroughly in a water bath at 30 °C for 24 hours, centrifuged, washed three times with ethanol and water, and then dried in a vacuum drying oven at 60 °C for 12 hours to obtain a yellowish-brown solid 1;

[0088] (4) After grinding 1.5 g of solid 1 thoroughly, place it in a tube furnace and calcine it at 900 °C for 2 hours in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain black solid 2.

[0089] (5) 1.0 g of solid 2 was added to 100 mL of 2.0 mol / L NaOH solution and stirred continuously for 24 hours at 50 °C. After centrifugation, washing with water and drying, black HPCS was obtained.

[0090] (6) Disperse 0.5 g HPCS and 64.0 mg CuCl2•H2O in a mixed solution of 100 mL deionized water and 700 mL ethanol, stir at 60 °C for 3 hours, filter, wash with ethanol 3 times, and dry to obtain solid 3;

[0091] (7) Place 0.2 g of solid 3 in a tube furnace and calcine it at 900 °C for 1 hour in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain Cu-HPCS-P without the addition of 1,10-phenanthroline.

[0092] Comparative Example 3: Preparation of Cu-HPCS-T

[0093] (1) Add 2.5 mL of ammonia (26.0%) to a mixed solution of 65 mL of ethanol and 15 mL of deionized water, stir in a 30°C water bath to mix thoroughly, then add 0.8 mL of formaldehyde solution (38.0%) and stir for 5 minutes to obtain solution A;

[0094] (2) Add 0.6 g of resorcinol quickly to solution A, and immediately add 6.0 mL of tetrapropoxysilane to obtain solution B;

[0095] (3) Solution B was stirred thoroughly in a water bath at 30 °C for 24 hours, centrifuged, washed three times with ethanol and water, and then dried in a vacuum drying oven at 60 °C for 12 hours to obtain a yellowish-brown solid 1;

[0096] (4) After grinding 1.5 g of solid 1 thoroughly, place it in a tube furnace and calcine it at 900 °C for 2 hours in a nitrogen atmosphere with a heating rate of 2 °C / min to obtain black solid 2.

[0097] (5) 1.0 g of solid 2 was added to 100 mL of 2.0 mol / L NaOH solution and stirred continuously for 24 hours at 50 °C. After centrifugation, washing with water and drying, black HPCS was obtained.

[0098] (6) Disperse 0.5 g HPCS, 64.0 mg CuCl2•H2O and 139.0 mg 1,10-o-phenanthroline in a mixed solution of 100 mL deionized water and 700 mL ethanol, stir at 60 °C for 3 hours, filter, wash with ethanol 3 times, and dry to obtain Cu-HPCS-T without high temperature calcination.

[0099] Test Example 1

[0100] 2.0 mg of HPCS, Cu-HPCS prepared in Example 1, Cu-HPCS-P prepared in Comparative Example 2, and Cu-HPCS-T prepared in Comparative Example 3 were added to 50 mL of 50 μM new pollutant solution, respectively. The solution was kept at natural pH, heated in a water bath at 30 °C, and magnetically stirred. H2O2 (20 mol / L) was added to trigger the reaction, and a new pollutant degradation experiment was conducted in the water. Samples were taken at fixed time points to detect the pollutant concentration. The new pollutants included bisphenol A (BPA), tetracycline (TC), ciprofloxacin (CIP), sulfamethoxazole (SMZ), and 2,4-dichlorophenol (2,4-DCP).

[0101] Figure 7The charts show the activity evaluation of HPCS prepared in Example 1, Cu-HPCS prepared in Comparative Example 2, and Cu-HPCS-T prepared in Comparative Example 3 in degrading BPA using H2O2. It can be seen that HPCS without Cu doping can only adsorb about 30% of BPA, and the addition of H2O2 did not induce further degradation of BPA. Both Cu-HPCS-P (without 1,10-phenanthroline) and Cu-HPCS-T (without high-temperature calcination) were able to continuously degrade BPA after the addition of H2O2, but only 60% was removed within 3 minutes. However, Cu-HPCS, by adding 1,10-phenanthroline and undergoing high-temperature treatment, firmly anchored Cu to the nanopores of HPCS, and after the addition of H2O2, could remove more than 95% of BPA within 1 minute. This indicates that Cu is the true active site for activating H2O2 and has extremely high catalytic activity. Furthermore, the addition of 1,10-phenanthroline, high-temperature treatment, and nanopores together effectively immobilized Cu, resulting in a higher catalytic water purification effect.

[0102] Figure 8 The images show the electron paramagnetic resonance (EPR) spectra of HPCS and Cu-HPCS prepared in Example 1, respectively, for the activation of H2O2 to produce •OH. To investigate the catalytic mechanism of Cu-HPCS activation of H2O2, EPR technology was used to explore the active species involved. Figure 8 The results showed that no obvious signal was detected in the HPCS+H2O2 system, while the Cu-HPCS+H2O2 system produced a significant DMPO-•OH adduct signal, indicating that Cu-HPCS effectively activated H2O2 into •OH, which is a key active species for the rapid removal of BPA. The hollow shell structure, abundant nanopores, and the introduction of Cu sites jointly contributed to the highly efficient purification of new pollutants in water.

[0103] Figure 9 The graph shows the activity evaluation of Cu-HPCS activated H2O2 prepared in Example 1 for degrading various novel pollutants. It can be seen that, except for BPA, the Cu-HPCS+H2O2 system can remove approximately 90% of TC, CIP, SMZ, and 2,4-DCP within 1 minute, indicating that the system has good applicability to different types of novel pollutants.

[0104] Figure 10The figures show the membrane continuous flow reaction results for pollutant removal by Cu-HPCS-P prepared in Comparative Example 2, Cu-HPCS-T prepared in Comparative Example 3, and Cu-HPCS prepared in Example 1. The catalyst was loaded onto the surface of a PVDF membrane to construct the membrane continuous flow reaction system shown in the figure. The results showed that during 14 days of continuous operation, the removal efficiency of Cu-HPCS for BPA remained close to 100%. Simultaneously, no release of Cu ions was detected in the effluent, indicating that the catalyst has good structural stability and metal immobilization ability. However, Cu-HPCS-P without the addition of 1,10-phenanthroline and Cu-HPCS-T without high-temperature calcination maintained approximately 80% BPA removal rate initially before gradually losing activity, indicating that the active Cu sites gradually disappeared. This further demonstrates that the addition of 1,10-phenanthroline, high-temperature treatment, and nanopores can fully immobilize the active Cu sites, thereby enabling them to exert highly efficient H2O2 activation activity within the confined space. The above results fully demonstrate the high purification performance of Cu-HPCS in advanced oxidation water treatment and its engineering feasibility for long-term continuous operation, laying the foundation for its practical application and promotion.

[0105] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and these variations still fall within the protection scope of the present invention.

Claims

1. A method for preparing a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst, characterized in that, The preparation method includes the following steps: (1) Add ammonia water to a mixed solution of ethanol and deionized water, stir in a water bath, add formaldehyde solution, and stir for 5 minutes to obtain solution A; (2) Add resorcinol to solution A, stir for 0-20 min, add tetrapropoxysilane to obtain solution B; (3) Stir in water bath, centrifuge, wash, and dry to obtain a yellowish-brown solid 1; (4) After grinding solid 1, it is calcined in an inert gas to obtain black solid 2; (5) Add solid 2 to sodium hydroxide solution, heat and stir, centrifuge, wash with water and dry to obtain black hollow porous nanospheres; (6) Empty porous nanospheres, copper chloride monohydrate and 1,10-o-phenanthroline were dispersed in a mixed solution of deionized water and ethanol, stirred at 30 °C, filtered, washed and dried to obtain solid 3; (7) Solid 3 was calcined in an inert gas to obtain a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst.

2. The method for preparing a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst according to claim 1, characterized in that, In step (1), the volume ratio of ammonia, formaldehyde solution, ethanol and deionized water is 1~10:0.5~5:65:

15.

3. The method for preparing a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst according to claim 1, characterized in that, In step (2), the ratio of resorcinol to solution A is 0.1~2g:81.5~95mL, and the volume ratio of tetrapropoxysilane to solution A is 1~10:81.5~95.

4. The method for preparing a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst according to claim 1, characterized in that, The water bath stirring time in step (3) is 12~48 h.

5. The method for preparing a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst according to claim 1, characterized in that, In steps (4) and (7), the calcination temperature is 500~1000 ℃.

6. The method for preparing a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst according to claim 1, characterized in that, In step (5), the concentration of the sodium hydroxide solution is 1~5 mol / L.

7. The method for preparing a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst according to claim 1, characterized in that, In step (6), the mass ratio of the hollow porous nanospheres, copper chloride monohydrate and 1,10-phenanthroline is 10~200:1~20:5~20.

8. The application of a copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst prepared by the preparation method according to any one of claims 1-7 in the degradation of pollutants in water, characterized in that, The contaminant is at least one of bisphenol A, tetracycline, ciprofloxacin, sulfamethoxazole, and 2,4-dichlorophenol.

9. The application of the copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst according to claim 8 in the degradation of pollutants in water, characterized in that, The method of application is as follows: copper-doped hollow porous nanosphere advanced oxidation water treatment catalyst is dispersed in a solution containing the pollutants, and then 20 mol / L hydrogen peroxide is added.

Images