A method for preparing an amorphous material for water pollution treatment and application

Abstract

The present application relates to a kind of preparation method and application of amorphous material for water pollution treatment.The method includes that copper salt and nitrogen / sulfur-containing organic ligand are dissolved in organic solvent respectively, after mixing, solvent thermal reaction is carried out, and the amorphous material is obtained after treatment.The material prepared by the present application is amorphous Cu (I)-S coordination polymer, the surface is rich in N / S functional site, and it has the multi-level pore structure of microporous-mesoporous cooperation.The material of the present application can quickly adsorb and enrich dye molecules when used for organic dye wastewater treatment, and simultaneously, through the high-efficiency activation of Cu (I)-S active site, active oxygen species mainly with singlet oxygen is generated to realize in-situ catalytic oxidation degradation of dye.The material of the present application is simple in preparation, low in cost, has very high removal efficiency for a variety of single and mixed dyes in wide pH range, and has stable performance in real water body, good recycling property, and has wide application prospect in wastewater treatment and other fields.

Description

Technical Field

[0001] This invention belongs to the field of water pollution treatment materials technology, and particularly relates to a method for preparing an amorphous material for water pollution treatment and its application. Background Technology

[0002] Organic dyes are widely used in industries such as printing and dyeing, textiles, papermaking, leather, plastics, inks, chemicals, and pharmaceuticals, generating large amounts of dye-containing wastewater during production. This wastewater typically exhibits high color intensity, complex composition, strong chemical stability, high biotoxicity, and difficulty in natural degradation. It not only severely impacts water transparency and ecosystem stability, but some dyes and their intermediates also pose mutagenic, carcinogenic, and bioaccumulative risks, posing a serious threat to both the ecological environment and human health. Therefore, developing novel functional materials capable of rapidly and efficiently removing organic dye pollutants under complex aquatic conditions has become an important research direction in the field of water pollution control.

[0003] Currently, the main methods for treating organic dye wastewater include physical adsorption, chemical oxidation, biodegradation, membrane separation, and advanced oxidation methods. Each method has its own advantages and disadvantages, but in practical applications, they still have shortcomings in terms of removal efficiency, applicability, treatment cost, and stability.

[0004] Adsorption is widely used in dye wastewater treatment due to its simplicity, low cost, and minimal equipment requirements. While adsorption can reduce color and dye concentration in wastewater quickly, it essentially only transfers pollutants from the liquid phase to the solid phase, without truly achieving complete degradation or mineralization. This leads to problems such as difficulty in adsorbent regeneration, a high risk of secondary pollution, and increased post-saturation treatment costs. Furthermore, many adsorbent materials exhibit a significantly reduced ability to capture certain dye molecules under neutral or alkaline conditions, limiting their application in practical wastewater treatment across a wide pH range.

[0005] Advanced oxidation technologies, particularly Fenton reactions and Fenton-like reactions, have garnered significant attention in organic wastewater treatment due to their ability to generate highly reactive oxygen species in situ, thereby efficiently destroying the conjugated structures and chromophores of organic pollutant molecules. Traditional Fenton reactions typically require strongly acidic conditions, have a narrow applicable pH range, and exhibit significantly reduced efficiency in neutral or even weakly alkaline environments. Furthermore, homogeneous Fenton systems suffer from drawbacks such as metal ion loss, high sludge production, and difficulty in catalyst recovery. To overcome these issues, researchers have developed various heterogeneous Fenton-like catalytic materials, including iron-based, copper-based, cobalt-based, and composite oxide materials. However, existing catalytic materials still generally suffer from the following shortcomings: First, some materials have insufficient exposure of active sites, making it difficult for pollutants to rapidly accumulate at the catalytic interface, resulting in slow reaction kinetics; second, the preparation processes for some crystalline materials are complex, requiring high control over morphology and crystal phase, which is unfavorable for large-scale preparation; third, many catalytic systems are susceptible to interference from coexisting ions, natural organic matter, and pH fluctuations under real wastewater conditions, leading to a decline in catalytic performance.

[0006] To improve the removal efficiency of organic dyes, some studies have attempted to combine adsorption materials with catalytic oxidation materials, concentrating pollutants through adsorption while simultaneously degrading them through oxidation. However, in existing systems, adsorption and catalysis often originate from different components, resulting in insufficient interfacial coupling and limited efficiency in pollutant migration from adsorption sites to catalytic sites, hindering rapid synergistic removal. Furthermore, multi-component composite materials often suffer from cumbersome preparation steps, uneven component dispersion, and insufficient structural stability, thus affecting their continued application in complex wastewater. Therefore, how to construct a single-material system that simultaneously possesses highly efficient adsorption and enrichment capabilities and strong catalytic oxidation activity to achieve synergistic enhancement of pollutant capture and in-situ degradation is a key problem urgently needing to be solved in this field.

[0007] Compared to traditional crystalline materials, amorphous materials possess structural characteristics of long-range disorder and short-range order. They typically exhibit richer unsaturated coordination sites, higher surface defect density, and more flexible local electronic structures, thus offering unique advantages in adsorption, catalysis, and interfacial reactions. Furthermore, amorphous materials are often prepared in milder processes with greater morphological tunability, making them more suitable for constructing hierarchical porous structures and heteroatom-rich active surfaces. Patent document CN103551172B, "An Amorphous Copper Catalyst and Its Application," primarily emphasizes the preparation of the amorphous copper catalyst itself and its catalytic degradation performance. It does not highlight the abundance of functional sites on the material surface, leaning more towards a single catalytic degradation function, and lacks sufficient coverage of the rapid pre-concentration mechanism of pollutants at the catalytic interface.

[0008] However, current research on amorphous materials in the treatment of organic dye wastewater remains relatively limited, especially regarding amorphous catalytic materials that can simultaneously achieve rapid adsorption, in-situ activation of oxidants, and efficient degradation of various dye molecules across a wide pH range. Existing materials also suffer from limitations such as simple pore structures, low utilization of active sites, and insufficient adaptability to complex real-world water bodies, making it difficult to meet the application requirements for rapid treatment of high-concentration, multi-type dye pollution. Summary of the Invention

[0009] The technical problems solved by this invention are: 1. Limited functionality and insufficient synergy: In existing technologies, materials for treating organic dyes typically have limited functionality. Simple adsorption methods cannot completely degrade pollutants, while simple catalytic oxidation methods suffer from slow surface enrichment and low mass transfer efficiency. Adsorption and catalytic functions fail to synergize effectively. 2. Limited applicability: The applicable pH range is narrow, and efficiency drops sharply under neutral or alkaline conditions, limiting their application in complex water bodies. 3. Inadequate material structure design: Some existing catalysts suffer from insufficient exposure of active sites, simple pore structures, and complex preparation processes, making it difficult to balance rapid mass transfer, efficient catalysis, and structural stability. 4. Poor universality in practical applications: Some materials are selective for dye types or exhibit significant performance degradation in real water bodies, making it difficult to meet the treatment needs of complex, high-concentration dye wastewater.

[0010] In view of the technical problems existing in the prior art, the present invention designs an adaptive amorphous material for water pollution treatment and its preparation method. It forms an amorphous Cu(I)-S nanostructure through the self-assembly of metal ions and nitrogen-sulfur ligands. The surface is rich in N / S functional sites and has a hierarchical porous structure with micropore-mesopore synergy. It can rapidly enrich organic dye molecules in wastewater. On this basis, the Cu(I)-S active sites are used to efficiently activate oxidants to generate active oxygen species mainly composed of hydroxyl radicals and singlet oxygen, thereby achieving rapid catalytic degradation of dye pollutants.

[0011] It should be noted that, in this invention, unless otherwise specified, the specific meaning of "comprising" in relation to composition definition and description includes both open-ended meanings such as "comprising," "including," etc., and closed-ended meanings such as "composed of," etc., and similar meanings.

[0012] To solve the aforementioned technical problems, the present invention adopts the following solution:

[0013] A method for preparing an amorphous material for water pollution treatment includes the following steps:

[0014] S1: Preparation of ligand precursor solution and copper salt precursor solution:

[0015] Nitrogen / sulfur-containing organic ligands are dissolved in an organic solvent to form a ligand precursor solution;

[0016] Copper salts are dissolved in organic solvents to form copper salt precursor solutions;

[0017] S2: Solvothermal self-assembly reaction:

[0018] The copper salt precursor solution and the ligand precursor solution are mixed and subjected to a solvothermal reaction, so that copper ions and the organic ligand self-assemble to form an amorphous Cu(I)-S coordination structure product.

[0019] S3: Separate, wash and dry the product after the reaction in step S2 to obtain the amorphous material for water pollution treatment.

[0020] Further, in step S1, the copper salt is at least one of copper chloride, copper nitrate, copper sulfate, or copper acetate;

[0021] The nitrogen / sulfur-containing organic ligand is 2,5-dimercapto-1,3,4-thiadiazole;

[0022] The organic solvent is at least one of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, or N-methylpyrrolidone.

[0023] Furthermore, in step S1, an acidic promoter is added to the ligand precursor solution;

[0024] The acid accelerator is at least one of trifluoroacetic acid, hydrochloric acid, sulfuric acid, nitric acid, acetic acid, and phosphoric acid.

[0025] The volume ratio of the acidic accelerator added to the total volume of the solution is 0.25%.

[0026] Furthermore, the mass ratio of the copper salt to the organic ligand is (1-10):1.

[0027] Furthermore, in step S2, the temperature of the solvothermal reaction is 100℃-160℃, and the reaction time is 6-24 hours.

[0028] Furthermore, in step S3, the washing is performed by washing the product after the reaction in step S2 with anhydrous ethanol to remove unreacted raw materials and residual solvent.

[0029] Furthermore, in step S3, the drying is vacuum drying, and the drying temperature is 40℃-80℃.

[0030] In this invention, there are no special restrictions on the centrifugation process in step S3, as long as solid-liquid separation can be achieved.

[0031] The present invention also discloses an amorphous material for water pollution treatment, which is prepared according to the above-described preparation method.

[0032] Furthermore, the material has an amorphous structure, its surface is rich in nitrogen and sulfur functional groups, it has a multi-level pore structure with micropores and mesopores working together, and its active center is a Cu(I)-S coordination structure.

[0033] The present invention also discloses the use of the above-mentioned amorphous material for water pollution treatment in the treatment of organic dye wastewater.

[0034] Regarding the amorphous material preparation and structure formation mechanism in this invention:

[0035] The successful preparation mechanism of this invention lies in the coordination self-assembly between metal ions and organic ligands. Under solvothermal conditions, Cu... 2+ It undergoes a coordination reaction with the thiol group (-SH) in the DMTD molecule.

[0036] It is worth noting that during the reaction process, Cu may have been involved. 2+ To Cu + The in-situ reduction ultimately formed a coordination polymer with Cu(I)-S as the main coordination mode. Due to the rapid progress of the coordination reaction and the self-assembly characteristics of metal ions and organic ligands, the molecules are restricted to long-range ordered arrangement, thus forming an amorphous structure with long-range disorder and short-range order.

[0037] Meanwhile, these primary nano-coordination polymer units tend to stack and aggregate, thus spontaneously constructing a multi-level pore structure with micropores and mesopores working together, and exposing a large number of uncoordinated N and S atoms on the material surface, which become functional sites.

[0038] The mechanism of the unique and superior effects of amorphous materials in this invention:

[0039] First, the "adsorption-catalysis" synergistic mechanism: the material's superior performance stems from its unique structural design. The abundant N / S functional groups and hierarchical pore structure on the surface, with micropores providing high specific surface area and strong adsorption sites, and mesopores promoting mass transfer, enable the rapid adsorption and enrichment of dye molecules to the material interface and within the pores. Subsequently, the highly exposed amorphous Cu(I)-S active centers efficiently activate H2O2, primarily generating hydroxyl radicals (·OH) and singlet oxygen (·OH). 1 Highly reactive oxygen species such as O2 are utilized. Because pollutants can be enriched near the active sites, "interfacial confined catalysis" is achieved, which greatly improves mass transfer efficiency and oxidant utilization, thereby enabling rapid and deep degradation.

[0040] Second, wide pH adaptability mechanism: traditional Fe 2+The / H2O2 Fenton system heavily relies on acidic conditions to maintain iron solubility and ·OH generation. The core of this invention is the Cu(I) / Cu(II) redox cycle. The Cu(I)-S structure can stably activate H2O2 over a wide pH range. The underlying mechanism is that under low pH conditions, the material catalyzes the generation of hydroxyl radicals from H2O2 to degrade dyes; as the pH increases, the main active species gradually transforms into singlet oxygen. This pH-dependent catalytic pathway conversion ensures that the material can still efficiently degrade organic dyes under complex acidic and alkaline environments. Simultaneously, the abundant S-defect sites and flexible local electronic structure of the amorphous structure help maintain the valence state cycle of the copper active center, thus ensuring efficient generation of active oxygen species even under neutral or weakly alkaline environments, achieving excellent performance over a wide pH range.

[0041] This invention provides a method for preparing an amorphous material for water pollution treatment and its application, which has the following beneficial effects:

[0042] This invention not only combines the dual advantages of enrichment and advanced oxidation synergistic removal, but also maintains excellent treatment performance over a wide pH range and has good applicability to various organic dyes and real water systems, thus providing a new technical solution for the efficient, low-cost and scalable treatment of organic dye wastewater.

[0043] 1. This invention achieves highly efficient synergy between adsorption and catalytic oxidation: The Cu-DMTD amorphous material prepared by this invention has a surface rich in N / S functional sites and a multi-level pore structure with micropore-mesopore synergy, which can rapidly adsorb and enrich dye molecules. Subsequently, the Cu(I)-S active centers in the material can efficiently activate H2O2, generating highly reactive oxygen species (such as hydroxyl radicals and singlet oxygen) in situ, which rapidly oxidize and degrade the enriched pollutants, significantly improving removal efficiency and oxidant utilization.

[0044] 2. This invention exhibits excellent wide pH adaptability and stability: The material of this invention maintains excellent dye removal performance across a wide pH range of 3-9 (e.g., the removal rate of Rhodamine B is >95% at both pH=3 and pH=7), overcoming the strong dependence of the traditional Fenton system on acidic conditions. Simultaneously, the material has a stable structure, strong Cu(I)-S coordination bonds, low metal leaching, and retains over 80% of its performance after 5 cycles of use.

[0045] 3. The material structure of this invention has significant advantages and fast reaction kinetics: the amorphous structure is rich in defects and unsaturated sites, combined with hierarchical channels, which increases the specific surface area and the exposure of active sites, accelerating the mass transfer and diffusion of dye molecules, thereby improving reaction kinetics. The material can achieve a high removal rate of over 91% for various dyes within 5 minutes.

[0046] 4. The preparation method of this invention is simple, widely applicable, and has practical application potential: it adopts a one-pot solvothermal method, using inexpensive and readily available raw materials, with a mild and simple process that is easy to scale up. The material of this invention exhibits highly efficient removal capabilities for dyes of various structural types, including Rhodamine B, Congo Red, Malachite Green, Methyl Violet, Chrome Black T, and Methylene Blue, and maintains a high removal rate of over 90% in real water bodies such as tap water and lake water, demonstrating strong anti-interference ability. Attached Figure Description

[0047] Figure 1 : This is a schematic diagram of the process for preparing Cu-DMTD amorphous material in an embodiment of the present invention;

[0048] Figure 2 The morphology, crystal structure and surface chemical state characterization of the Cu-DMTD amorphous material prepared in Example 1 of this invention are as follows: (a) Transmission electron microscopy image of the morphology; (b) XRD diffraction peak test pattern; (c) Cu LM2 photoelectron spectrum; (d) Cu 2pXPS photoelectron spectrum.

[0049] Figure 3 The following are test diagrams of the micropore-mesopore structure of the Cu-DMTD material prepared in Example 1 of this invention: (a) nitrogen adsorption-desorption isotherm of the sample; (b) mesopore size distribution calculated based on the BJH model; (c) micropore size distribution. Detailed Implementation

[0050] The present invention will be further described below with reference to specific embodiments and accompanying drawings:

[0051] All raw materials and reagents used in the examples are commercially available products, which can be purchased through commercial channels and used directly according to the product instructions. For conventional reagents whose suppliers are not specified in the examples, those skilled in the art can obtain and use them based on common knowledge in the field or conventional experimental methods.

[0052] Copper chloride (CuCl2) was used as the copper source, 2,5-dimercapto-1,3,4-thiadiazole (DMTD) as the organic ligand, and N,N-dimethylformamide (DMF) as the reaction solvent and auxiliary reagent. Hydrogen peroxide was used in a 30 wt% aqueous solution. Acetic acid (HAc) and sodium acetate (NaAc) were used to prepare the buffer solution. All solutions and buffer solutions were prepared with deionized water.

[0053] Example 1

[0054] S1: Preparation of organic ligand solution and copper salt precursor solution.

[0055] Weigh 0.02 g (0.13 mmol) of DMTD, add it to 2 mL of DMF to dissolve it, and then add 10 μL of trifluoroacetic acid to obtain the ligand precursor solution.

[0056] Another 0.06 g (0.45 mmol) of CuCl2 was added to 2 mL of DMF and dissolved thoroughly to obtain a copper salt precursor solution.

[0057] S2: Solvothermal self-assembly reaction

[0058] The DMTD precursor solution and CuCl2 precursor solution were mixed and transferred together to a 20 mL polytetrafluoroethylene-lined reactor. The reactor was sealed and placed in an oven at 130°C for 12 h. During this process, Cu... 2+ It undergoes self-assembly and coordination reactions with DMTD to form a Cu(I)-S coordination structure, which is further constructed into an amorphous porous material. After the reaction is complete, it is naturally cooled to room temperature.

[0059] S3: Product Separation and Purification

[0060] The mixture after the S2 reaction was removed and centrifuged at 10,000 rpm for 5 min to collect the precipitate. The precipitate was washed with anhydrous ethanol to remove unreacted raw materials and residual solvent, followed by another centrifugation. Finally, the washed product was dried under vacuum at 50°C to obtain Cu-DMTD amorphous material. The preparation process is as follows: Figure 1 As shown.

[0061] The materials used in Embodiment 1 of the present invention underwent corresponding tests and characterization:

[0062] Figure 2 The morphology and surface properties of the Cu-DMTD amorphous material prepared in Example 1 of this invention are tested as follows: (a) Transmission electron microscope image of the morphology; (b) XRD diffraction peak test pattern; (c) Cu LM2 photoelectron spectrum; (d) Cu 2p XPS photoelectron spectrum.

[0063] pass Figure 2 As can be seen from this, the Cu-DMTD prepared in Example 1 of the present invention is in an amorphous state;

[0064] pass Figure 2 b. As can be seen, no sharp crystal diffraction peaks appeared in the XRD pattern, but only a broad diffraction pattern was observed, which further confirms that the prepared Cu-DMTD material belongs to a typical amorphous structure.

[0065] pass Figure 2As can be seen from c, a distinct characteristic peak appears at 916.9 eV in the Cu LMM Auger spectrum, which is typical of monovalent copper (Cu). + The characteristic signal indicates the presence of copper in a low valence state in the material; through Figure 2 As can be seen from d, in the high-resolution Cu 2p XPS spectrum, the obvious double peaks belong to the Cu 2p3 / 2 and Cu 2p1 / 2 orbitals, respectively, and almost no obvious divalent copper (Cu) is observed in the 940-945 eV range. 2+ Characteristic satellite peaks. Combined with the Cu-S bond signal fitted in the figure, this fully demonstrates that copper in this material is mainly monovalent (Cu). + It exists in the form of ) and successfully coordinates with the sulfur atom in the ligand to form a Cu-S bond.

[0066] Figure 3 The image shows the microporous-mesoporous structure test diagram of the Cu-DMTD material prepared in Example 1 of this invention, where (a) is the nitrogen adsorption-desorption isotherm; (b) is the mesoporous pore size distribution curve; and (c) is the microporous pore size distribution curve.

[0067] pass Figure 3 As can be seen, the nitrogen adsorption-desorption isotherm of this material exhibits typical type IV isotherm characteristics. In the region with relatively high relative pressures (P / P0) (approximately 0.4-1.0), the adsorption and desorption branches do not coincide, forming a distinct H3-type hysteresis loop, indicating the presence of abundant mesoporous structures within the Cu-DMTD material. Simultaneously, at extremely low relative pressures, the curve shows a significant increase in adsorption capacity, suggesting the existence of microporous structures within the material.

[0068] pass Figure 3 As can be seen from b, the mesopore size of this material is mainly distributed between 3-10 nm, and gradually decreases in a wider region (up to 21 nm). This further confirms that the material has well-developed mesopore channels, and this relatively open mesopore structure is conducive to promoting the rapid mass transfer and diffusion of pollutant molecules and reactive substances during catalytic degradation.

[0069] pass Figure 3 As can be seen from c, the material exhibits an extremely sharp and narrow characteristic peak at approximately 1.5 nm, which fully demonstrates that the Cu-DMTD material contains a large number of microporous structures with highly uniform pore size distribution. Based on the above analysis, the Cu-DMTD prepared in Example 1 of this invention is a hierarchical porous material possessing both microporous and mesoporous characteristics. This structure can provide a large specific surface area and abundant surface active sites.

[0070] Example 2

[0071] Weigh 0.02 g (0.13 mmol) of DMTD, add it to 2 mL of DMF to dissolve it, and then add 10 μL of trifluoroacetic acid to obtain the ligand precursor solution.

[0072] Another 0.02 g (0.149 mmol) of CuCl2 was added to 2 mL of DMF and dissolved thoroughly to obtain a copper salt precursor solution.

[0073] S2: Solvothermal self-assembly reaction

[0074] The DMTD precursor solution and CuCl2 precursor solution were mixed and transferred together to a 20 mL polytetrafluoroethylene-lined reactor. The reactor was sealed and placed in an oven at 100°C for 24 h. During this process, Cu... 2+ It undergoes self-assembly and coordination reactions with DMTD to form a Cu(I)-S coordination structure, which is further constructed into an amorphous porous material. After the reaction is complete, it is naturally cooled to room temperature.

[0075] S3: Product Separation and Purification

[0076] The mixture after the S2 reaction was removed and centrifuged at 10,000 rpm for 5 min to collect the precipitate. The precipitate was washed with anhydrous ethanol to remove unreacted raw materials and residual solvent, followed by centrifugation again. Finally, the washed product was dried under vacuum at 80 °C to obtain Cu-DMTD amorphous material.

[0077] Example 3

[0078] Weigh 0.02 g (0.13 mmol) of DMTD, add it to 2 mL of DMF to dissolve it, and then add 10 μL of trifluoroacetic acid to obtain the ligand precursor solution.

[0079] Another 0.2 g (1.49 mmol) of CuCl2 was added to 2 mL of DMF and dissolved thoroughly to obtain a copper salt precursor solution.

[0080] S2: Solvothermal self-assembly reaction

[0081] The DMTD precursor solution and CuCl2 precursor solution were mixed and transferred together to a 20 mL polytetrafluoroethylene-lined reactor. The reactor was sealed and placed in an oven at 160°C for 6 h. During this process, Cu... 2+ It undergoes self-assembly and coordination reactions with DMTD to form a Cu(I)-S coordination structure, which is further constructed into an amorphous porous material. After the reaction is complete, it is naturally cooled to room temperature.

[0082] S3: Product Separation and Purification

[0083] The mixture after the S2 reaction was removed and centrifuged at 10,000 rpm for 5 min to collect the precipitate. The precipitate was washed with anhydrous ethanol to remove unreacted raw materials and residual solvent, followed by centrifugation again. Finally, the washed product was dried under vacuum at 40 °C to obtain Cu-DMTD amorphous material.

[0084] Example 4

[0085] In Example 4 of the present invention, the basic operation and conditions are the same as in Example 1, except that the copper salt is copper nitrate, the solvent is N,N-dimethylacetamide, and the acidic promoter is nitric acid, so as to prepare the Cu-DMTD amorphous material.

[0086] Example 5

[0087] In Example 5 of the present invention, the basic operation and conditions are the same as in Example 1, except that copper salt is selected as copper sulfate, solvent is selected as dimethyl sulfoxide, and acid promoter is selected as phosphoric acid, so as to prepare the Cu-DMTD amorphous material.

[0088] Example 6

[0089] In Example 6 of the present invention, the basic operation and conditions are the same as in Example 1, except that the copper salt is copper acetate, the solvent is N-methylpyrrolidone, and the acid accelerator is sulfuric acid, so as to prepare the Cu-DMTD amorphous material.

[0090] The Cu-DMTD amorphous materials prepared in Examples 2-6 of this invention are all rich in nitrogen and sulfur functional groups on their surface, have a multi-level pore structure with micropores and mesopores working together, and their active center is a Cu(I)-S coordination structure.

[0091] Performance testing of the Cu-DMTD amorphous material prepared in this invention

[0092] First, the performance of the Cu-DMTD amorphous material prepared in Example 1 in removing Rhodamine B (RhB) was tested. The specific test steps are as follows:

[0093] Step 1: Preparation of RhB reaction solution

[0094] RhB solutions were prepared using HAc-NaAc buffer at a concentration of 50 mg / L, and the pH of the system was adjusted to 3-9. 9.5 mL of this RhB buffer was used as the reaction substrate for each experiment.

[0095] Step 2: Oxidation reaction

[0096] Add 0.5 mL of 30 wt% H2O2 aqueous solution to the system and stir continuously for 3 min at room temperature. At this time, the Cu(I)-S active sites in the Cu-DMTD material can activate H2O2, generating reactive oxygen species mainly composed of singlet oxygen and hydroxyl radicals, which rapidly oxidize and degrade RhB.

[0097] Immediately after the reaction was complete, 2 mL of the reaction solution was taken, filtered through a 0.22 μm Millipore filter membrane, and the residual RhB concentration in the solution was measured at 554 nm using a UV-Vis spectrophotometer. The initial concentration C0 and the concentration C at a certain time were used as the reference values. t Calculate the degradation rate R.

[0098] R = (1-C t / C o ) × 100%

[0099] The results showed that under the above conditions, the total removal rates of RhB were 99.28%, 98.79%, 95.57%, 95.29%, and 94.55% at pH values ​​of 3, 4, 5, 7, and 9, respectively.

[0100] Secondly, regarding the universality experiment of Cu-DMTD material in removing various dyes.

[0101] To investigate the applicability of Cu-DMTD materials to different organic dyes, Congo Red (CR), Malachite Green (MG), Methyl Violet 10B (MV 10B), Eriochrome Black T (EBT), and Methylene Blue (MB) were selected as model pollutants.

[0102] The experimental conditions were as follows: the initial concentration of dye was 100 mg / L, the pH of the system was 7, and the catalyst dosage was 0.6 g / L.

[0103] The results showed that the total removal rates of the five dyes within 5 minutes were 99.64%, 99.94%, 99.08%, 99.23%, and 91.23%, respectively. This indicates that the material has excellent catalytic degradation ability for organic dyes with different structural types.

[0104] Thirdly, the Cu-DMTD material in Example 1 of this invention was used in a mixed dye removal experiment in real water.

[0105] First, the experiment with mixed dyes in deionized water.

[0106] A mixed dye solution containing 10 mg / L RhB, 60 mg / L MV 10B, 100 mg / L CR, 20 mg / L MB, and 100 mg / L MG was prepared in a 15 mL reaction vessel, along with 3 wt% H2O2 and 0.6 g / L Cu-DMTD catalyst. The mixture was then magnetically stirred for 10 min at room temperature.

[0107] Take 3 mL samples at 1 min, 3 min and 5 min respectively, and measure the absorbance of each dye at the corresponding maximum absorption wavelength: RhB is 554 nm, MV 10B is 583 nm, CR is 497 nm, MB is 664 nm and MG is 617 nm.

[0108] The removal rate R of each dye is calculated based on the change in absorbance.

[0109] R = (1-C t / C o ) × 100%

[0110] The results showed that the removal rates of each dye reached 97.8%, 95.3%, 92.7%, 94.6% and 96.1% within 10 minutes, respectively.

[0111] Second, experiments with mixed dyes in tap water and lake water.

[0112] In a 15 mL reaction vessel, a mixed dye solution was prepared with tap water, consisting of RhB 10 mg / L, MV10B 40 mg / L, CR 100 mg / L, MB 10 mg / L, and MG 30 mg / L. 6 wt% H2O2 and 0.6 g / L Cu-DMTD catalyst were added, and the mixture was magnetically stirred at room temperature for 45 min. 5 mL samples were taken every 15 min, and the absorbance at the corresponding absorption wavelength was measured to calculate the removal rate.

[0113] The lake water experiment was the same, except that tap water was replaced with collected lake water.

[0114] The results showed that the removal rates of MG, MV 10B, RhB, MB and CR in tap water within 45 min were 98.52%, 98.51%, 98.42%, 97.53% and 95.94%, respectively.

[0115] The removal rates of RhB, MB, MG, MV 10B, and CR in the lake water were 98.22%, 97.82%, 97.80%, 97.44%, and 95.21%, respectively. These experiments demonstrate that the material maintains good treatment performance in complex real-world water bodies.

[0116] When used in the treatment of organic dye wastewater, the material of this invention can rapidly adsorb and enrich dye molecules. Simultaneously, it efficiently activates H₂O₂ through Cu(I)-S active sites to generate reactive oxygen species, primarily singlet oxygen, achieving in-situ catalytic oxidative degradation of the dyes. This material is simple to prepare, low in cost, and exhibits extremely high removal efficiency for various single and mixed dyes over a wide pH range. Furthermore, it demonstrates stable performance in real water bodies, good recyclability, and broad application prospects in wastewater treatment and other fields.

[0117] The present invention has been described above by way of example with reference to the embodiments and accompanying drawings. Obviously, the implementation of the present invention is not limited to the above-described manner. Any improvements made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A method for the preparation of an amorphous material for water pollution treatment, characterized by, Includes the following steps: S1: Preparation of ligand precursor solution and copper salt precursor solution: Nitrogen / sulfur-containing organic ligands are dissolved in an organic solvent to form a ligand precursor solution; Copper salts are dissolved in organic solvents to form copper salt precursor solutions; S2: Solvothermal self-assembly reaction: The copper salt precursor solution and the ligand precursor solution are mixed and subjected to a solvothermal reaction, so that copper ions and the organic ligand self-assemble to form an amorphous Cu(I)-S coordination structure product. S3: Separate, wash and dry the product after the reaction in step S2 to obtain the amorphous material for water pollution treatment.

2. The method for preparing amorphous materials for water pollution treatment according to claim 1, characterized in that: In step S1, the copper salt is at least one of copper chloride, copper nitrate, copper sulfate, or copper acetate. The nitrogen / sulfur-containing organic ligand is 2,5-dimercapto-1,3,4-thiadiazole; The organic solvent is at least one of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, or N-methylpyrrolidone.

3. The method for preparing amorphous materials for water pollution treatment according to claim 1, characterized in that: In step S1, an acidic promoter is also added to the ligand precursor solution; The acid accelerator is at least one of trifluoroacetic acid, hydrochloric acid, sulfuric acid, nitric acid, acetic acid, and phosphoric acid. The volume ratio of the acidic accelerator added to the total volume of the solution is 0.25%.

4. The method for preparing amorphous materials for water pollution treatment according to claim 1, characterized in that: The mass ratio of the copper salt to the organic ligand is (1-10):

1.

5. The method for preparing amorphous materials for water pollution treatment according to claim 1, characterized in that: In step S2, the temperature of the solvothermal reaction is 100℃-160℃, and the reaction time is 6-24 hours.

6. The method for preparing amorphous materials for water pollution treatment according to claim 1, characterized in that: In step S3, the washing is performed by washing the product after the reaction in step S2 with anhydrous ethanol to remove unreacted raw materials and residual solvent.

7. The method for preparing amorphous materials for water pollution treatment according to claim 1, characterized in that: In step S3, the drying is vacuum drying, and the drying temperature is 40℃-80℃.

8. An amorphous material for water pollution treatment, characterized by: It is prepared according to the preparation method described in any one of claims 1-7.

9. The amorphous material for water pollution treatment according to claim 8, characterized in that: The material has an amorphous structure, its surface is rich in nitrogen and sulfur functional groups, it has a multi-level pore structure with micropores and mesopores working together, and its active center is a Cu(I)-S coordination structure.

10. The use of the amorphous material for water pollution treatment as described in claim 8 in the treatment of organic dye wastewater.

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