Prussian blue analogue catalytic material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of water repair catalytic materials, in particular to a Prussian blue analogue catalytic material as well as a preparation method and application thereof. The Cu-Co double-site Prussian blue analogue catalytic material rich in oxygen vacancy is successfully synthesized through a simple thermal polymerization process, the catalytic material has high reaction activity and high electron mobility, and the preparation process is simple and convenient. And carrying out heat treatment on the precursor in a protective atmosphere to form a three-dimensional crystal network which has oxygen defects and uses cyanide ions as a bridge to connect transition metal ions and copper ions. In the efficient activation process of the PMS, the oxygen vacancy defect can capture oxygen atoms from the PMS in a high-selectivity mode, the internal conductivity and the electron transfer rate are remarkably improved, oriented electron transfer is achieved, and therefore further conversion of the high-salt organic wastewater is promoted.

Description

Technical Field

[0001] The invention relates to the technical field of water remediation catalytic materials, and in particular to a Prussian blue analogue catalytic material and a preparation method and application thereof. Background Art

[0002] In order to meet the continuous increase in material demand of the growing population, various industries around the world, such as manufacturing, agriculture and pharmaceutical industries, have over-expanded to increase production capacity. However, with the acceleration of industrialization, a large amount of high-salinity organic wastewater is produced in different water matrices. This wastewater contains high concentrations of organic pollutants that are difficult to decompose, including phenols, antibiotics, endocrine disruptors and synthetic pigments. The guarantee of clean water resources is the key to promoting the survival and development of human society, while the discharge of wastewater that has not been properly treated poses a major threat to the ecosystem and human health, affecting the process of sustainable development. Therefore, how to develop a technology that is both efficient, economical and environmentally friendly to treat high-salinity organic wastewater in water matrices has become a key issue that needs to be solved urgently.

[0003] Among many emerging water remediation technologies, the removal of residual organic pollutants in high-salinity wastewater mainly relies on membrane treatment, adsorption and advanced oxidation processes. Although membrane treatment and adsorption methods show high efficiency in removing organic pollutants, they have the disadvantages of high cost, complex process and inability to completely degrade pollutants. In contrast, the rational use of advanced oxidation processes is expected to solve this problem. However, research on efficient activation of PMS to quickly remove high-salinity organic wastewater is relatively limited, and it still faces difficulties such as improving catalyst activity, optimizing reaction conditions and regulating reaction mechanisms. Among them, transition metal catalysts can be efficiently activated without external energy input compared with other activation methods, such as heat treatment, photoelectric effect, microwave, etc., and have greater environmental and economic benefits. Therefore, the development of heterogeneous transition metal catalysts with simple preparation process, high reaction activity and reusability has become an urgent problem to be solved in the current research field.

[0004] Prussian blue analogs (PBAs), as a special type of metal-organic framework (MOFs) materials, have a variety of superior properties that make them ideal candidates for activating PMS in advanced oxidation processes. These properties include: (1) an open three-dimensional porous framework structure that can promote the diffusion and transport of pollutants and ensure the uniform dispersion of active sites. (2) dual transition metal sites can interact to trigger synergistic effects. (3) PBAs can exhibit excellent stability over a wide pH range. Previous studies have shown that PBA-based materials generally have problems such as unstable crystal structure and easy decomposition during the recycling process, which greatly limits their effectiveness in practical applications. Therefore, in order to achieve both high reactivity and excellent recyclability, it is necessary to combine multiple synthetic strategies for optimization design. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art, provide a Prussian blue analogue catalytic material and a preparation method and application thereof, and solve the technical problems of low activity, poor stability and complex synthesis process of existing transition metal catalysts.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a method for preparing a Prussian blue analogue catalytic material, comprising the following steps: Soluble copper salt, transition metal potassium cyanide and polyvinyl pyrrolidone are placed in a solvent system, and copper ions, transition metal ions and cyanide ions undergo coordination reaction to form a complex, which is then subjected to coprecipitation treatment to obtain a precursor; the precursor is heat-treated under a protective atmosphere to form a three-dimensional crystal network with oxygen defects that uses cyanide ions as bridges to connect transition metal ions and copper ions, thereby obtaining a Prussian blue analogue catalytic material; wherein the transition metal is cobalt or iron.

[0007] Optionally, the molar ratio of the soluble copper salt to the transition metal potassium cyanide is 2-8:3-12.

[0008] Optionally, the mass ratio of the soluble copper salt to the polyvinyl pyrrolidone is 5 to 11:8.

[0009] Optionally, the heat treatment temperature is 300°C to 900°C.

[0010] Optionally, the coprecipitation treatment is carried out at a temperature of 20°C to 30°C.

[0011] Optionally, the solvent of the solvent system is water.

[0012] Optionally, the soluble copper salt includes any one of copper nitrate, copper sulfate and copper chloride.

[0013] Optionally, the potassium cobalt cyanide is C6CoK3N6, the copper nitrate is Cu(NO3)2·3H2O, the copper sulfate is CuSO4·5H2O, and the copper chloride is CuCl2·2H2O.

[0014] The present invention provides a Prussian blue analogue catalytic material prepared by the preparation method of the Prussian blue analogue catalytic material.

[0015] The present invention provides an application of the above-mentioned Prussian blue analogue catalytic material in degrading high-salinity organic wastewater.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention successfully synthesizes a Cu-Co dual-site Prussian blue analog catalytic material rich in oxygen defects through a simple thermal polymerization process. The catalyst has high reactivity, high electron mobility, and a simple preparation process. The Prussian blue analog catalytic material / PMS synergistic catalytic process can rapidly produce a variety of highly active species, thereby effectively repairing and purifying pollutants in high-salt organic wastewater. By heat treating the precursor under a protective atmosphere, a three-dimensional crystal network with oxygen defects is formed, which uses cyanide ions as a bridge to connect transition metal ions and copper ions. In the efficient activation process of PMS, oxygen vacancy defects can highly selectively capture oxygen atoms from PMS, significantly improve the internal conductivity and electron transfer rate, and realize directional electron transfer, thereby promoting the further conversion of high-salt organic wastewater, thereby solving the technical problems of low activity, poor stability and complex synthesis process of existing transition metal catalysts. In addition, the three-dimensional crystal network with cyanide ions as bridges connecting transition metal ions and copper ions effectively regulates the diffusion and transport of pollutants, ensuring the uniform distribution of active sites, thereby accelerating the efficient decomposition of PMS and achieving the degradation and removal of pollutants in high-salt organic wastewater.

[0017] 2. The catalytic material prepared by the present invention not only exhibits excellent catalytic activity, but also has excellent recyclability and structural stability. The material can still maintain efficient catalytic performance after multiple consecutive tests, ensuring its economy and reliability in long-term applications. In addition, the Prussian blue analog catalytic material / PMS synergistic catalytic process can not only maintain high efficiency in a wide pH range, but also ensure effective treatment and purification of wastewater in harsh water quality environments such as high concentrations of inorganic anions and actual water bodies. Prussian blue analog catalytic materials are expected to be used for wastewater purification in industrial production, pharmaceutical factories, hospitals and other fields, as well as for the rapid removal of antibiotic residues in animal husbandry and aquaculture.

[0018] 3. The method for preparing the catalytic material of the present invention is innovative, simple to operate, uses cheap and readily available raw materials, and has low cost. The prepared Prussian blue analog catalytic material effectively adjusts the surface electronic state of the catalyst and enhances the exposure of active sites by introducing a large number of oxygen vacancies, and catalytically degrades pollutants in high-salt organic wastewater by efficiently activating PMS. In addition, the Prussian blue analog catalytic material / PMS synergistic catalytic process has removal rates of 100%, 100%, 100%, 100%, 100%, 96%, 92%, 93% and 86% for rhodamine B, methyl blue, methyl orange, tetracycline, chloroquine phosphate, norfloxacin, phenol, sulfamethoxazole and sulfamethoxazole in the solution, respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1The scanning electron microscope images of the Prussian blue analogue catalytic material prepared by the present invention are shown in Figure 1. (a) is a scanning electron microscope image at a scale of 5 micrometers, (b) is a scanning electron microscope image at a scale of 1 micrometer, and (c) is a scanning electron microscope image at a scale of 200 nm.

[0020] Figure 2 The test graphs of the degradation of chloroquine phosphate by the Prussian blue analogue catalytic material alone, the degradation of chloroquine phosphate by PMS alone, the degradation of chloroquine phosphate by peroxydisulfate alone and hydrogen peroxide alone, the degradation of chloroquine phosphate by the Prussian blue analogue catalytic material / PDS process, and the degradation of chloroquine phosphate by the Prussian blue analogue catalytic material / PMS process prepared in Comparative Example 1 of the present invention. (a) is a statistical graph of the test results, and (b) is a statistical graph of the data fitting results in (a).

[0021] Figure 3 The degradation test diagram of high-salt organic wastewater and different pollutants within 25 minutes after the Prussian blue analogue catalytic material prepared by the present invention activates PMS. (a) is a statistical diagram of the test results, and (b) is a statistical diagram of the data fitting results in (a).

[0022] Figure 4 This is a test chart of the degradation of high-salt organic wastewater and different pollutants within 80 minutes after the Prussian blue analogue catalytic material prepared by the present invention activates PMS.

[0023] Figure 5 This is a test diagram of the degradation of chloroquine phosphate at different pH values ​​after the Prussian blue analogue catalytic material prepared by the present invention activates PMS.

[0024] Figure 6 This is a test diagram of the degradation of chloroquine phosphate in the coexisting anion after the Prussian blue analog catalytic material prepared by the present invention activates PMS.

[0025] Figure 7 This is a test diagram of the degradation of chloroquine phosphate in different water qualities after the Prussian blue analog catalytic material prepared by the present invention activates PMS. DETAILED DESCRIPTION

[0026] In order to solve the above technical problems, the present invention provides a Prussian blue analogue catalytic material and a preparation method and application thereof. The technical scheme and embodiments of the present invention are now described in detail in conjunction with the accompanying drawings.

[0027] Chloroquine phosphate, the full English name is Chloroquine diphosphate, referred to as CQP.

[0028] Persulfate, the full English name is peroxymonosulfate, abbreviated as PMS.

[0029] Polyvinylpyrrolidone, the full English name is Polyvinylpyrrolidone, abbreviated as PVP.

[0030] Peroxydisulfate, the full English name is Peroxydisulfate, abbreviated as PDS.

[0031] In order to effectively deal with the low degradation efficiency of existing catalysts in the process of persulfate activation and the unsatisfactory performance in the treatment of high-salt organic wastewater, it is urgent to start from the design of catalysts and reaction mechanisms to break through the bottleneck of activity attenuation of traditional catalysts in high-salt environments. By developing materials with higher catalytic activity and excellent stability, and optimizing the dual-site synergistic effect of the catalytic system, the activation efficiency of persulfate and its degradation ability in complex wastewater systems can be significantly improved, thereby providing a more feasible technical path for the efficient treatment of high-salt organic wastewater.

[0032] The use of Prussian blue analogue catalytic materials in the process of activating persulfate to degrade pollutants differs significantly from that of conventional catalysts on multiple levels, especially in the setting of catalytic reaction conditions and reaction mechanism.

[0033] First, due to its unique crystal structure and electronic properties, the Prussian blue analogue catalytic material can maintain high catalytic activity in a high-salinity environment, avoiding the activity attenuation or failure of conventional catalysts due to the interference of salt ions under high salt concentrations. Therefore, when using Prussian blue analogue catalytic materials, PMS can still be efficiently activated in wastewater with higher salinity, while conventional catalysts often require special adjustments or advance treatment in such environments to adapt to high-salinity conditions.

[0034] Secondly, the method of using Prussian blue analogue catalytic materials is also different in the choice of reaction conditions. Traditional catalysts usually require higher temperatures or specific pH conditions to effectively activate PMS, while Prussian blue analogue catalytic materials can achieve efficient activation of PMS and effectively generate strong oxidative free radicals and non-free radicals in a relatively mild reaction environment, such as neutral or weakly acidic pH, normal temperature and pressure. This makes it more flexible and adaptable when treating complex wastewater.

[0035] The present invention is described in detail below through specific examples. The examples are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0036] Example 1 A method for preparing a Prussian blue analogue catalytic material comprises the following steps: (1) Dissolve 0.003 mol potassium cobalt cyanide in 30 mL deionized water and stir at a stirring speed of 500 r / min to form solution A. Then, dissolve 0.002 mol copper nitrate and 0.6 g PVP in 30 mL deionized water and stir at a stirring speed of 500 r / min to form a mixed solution B.

[0037] PVP (polyvinyl pyrrolidone) acts as a stabilizer and protective agent, which can prevent metal ion aggregation, inhibit side reactions, promote uniform dispersion, and improve the uniformity and controllability of the product by regulating crystal growth. In addition, PVP also improves the solubility of metal salts, helps maintain the stability of the reaction system, and thus optimizes the synthesis process and quality of the material.

[0038] (2) The mixed solution B obtained in step (1) was added dropwise to the solution A at a stirring speed of 500 r / min at a dropping speed of 1 mL / min, followed by co-precipitation treatment at 25°C, and then dried in a constant temperature forced air drying oven at 60°C for 12 h to obtain a Prussian blue analog precursor catalytic material.

[0039] Through the co-precipitation process, copper ions and transition metal ions can be evenly mixed on a microscopic scale, providing a uniformly distributed metal ion source for the subsequent formation of a metal-organic framework, which is conducive to the formation of a metal-organic framework material with a regular structure.

[0040] (3) The catalytic material obtained in step (2) is placed in a tubular furnace and subjected to heat treatment at 800° C. in three different atmospheres of nitrogen, hydrogen and argon using a thermal polymerization process. After heat treatment for 2 h, a Prussian blue analogue catalytic material is obtained.

[0041] The method for activating PMS by using Prussian blue analogue catalytic materials to degrade and remove pollutants from high-salinity organic wastewater is as follows: Ultrapure water was used to prepare 9 pollutant solutions, namely rhodamine B (RhB), methyl blue (MB), methyl orange (MO), tetracycline (TC), chloroquine phosphate (CQP), norfloxacin (NOR), phenol, sulfamethoxazole and sulfamethoxazole. Without changing the initial concentration, 30 mL of the above pollutant solutions were added with 20 mg of Prussian blue analogue catalytic material and 10 mg of PMS. The reaction was stirred for 1200 s at a stirring speed of 500 r / min. The degradation effect was shown in Figure 2. Figure 3 and Figure 4 .

[0042] Example 2 A method for preparing a Prussian blue analogue catalytic material comprises the following steps: (1) Dissolve 0.006 mol potassium cobalt cyanide in 30 mL deionized water and stir at a stirring speed of 500 r / min to form solution A. Then, dissolve 0.004 mol copper nitrate and 0.6 g PVP in 30 mL deionized water and stir at a stirring speed of 500 r / min to form a mixed solution B.

[0043] (2) The mixed solution B obtained in step (1) was added dropwise to the solution A at a stirring speed of 500 r / min at a dropping speed of 1 mL / min, followed by co-precipitation treatment at 25°C, and then dried in a constant temperature forced air drying oven at 60°C for 12 h to obtain a Prussian blue analog precursor catalytic material.

[0044] (3) The catalytic material obtained in step (2) is placed in a tubular furnace and subjected to heat treatment at 800° C. in three different atmospheres of nitrogen, hydrogen and argon using a thermal polymerization process. After heat treatment for 3 h, a Prussian blue analogue catalytic material is obtained.

[0045] The specific steps of the method for removing high-salt organic wastewater pollutants by activating PMS with Prussian blue analogue catalytic materials are as follows: Ultrapure water was taken as the background water sample, and the chloroquine phosphate pollutant solution was prepared with the water sample and mixed evenly, and its pH was changed to 2-11 to simulate the reality of removing pollutants from water bodies in complex water samples. 30 mL of the above pollutant solution was taken, and the Prussian blue analogue catalytic material was added to the water sample at a dosage of 20 mg, and then 10 mg of PMS was added. The reaction was stirred for 1200 s at a stirring speed of 300 r / min, so that the organic pollutants in the water were effectively degraded. The degradation situation is shown in FIG. Figure 5 shown.

[0046] Example 3 A method for preparing a Prussian blue analogue catalytic material comprises the following steps: (1) Dissolve 0.009 mol potassium cobalt cyanide in 30 mL deionized water and stir at a stirring speed of 500 r / min to form solution A. Then, dissolve 0.006 mol copper nitrate and 0.6 g PVP in 30 mL deionized water and stir at a stirring speed of 500 r / min to form a mixed solution B.

[0047] (2) The mixed solution B obtained in step (1) was added dropwise to the solution A at a stirring speed of 500 r / min at a dropping speed of 1 mL / min, followed by co-precipitation treatment at 25°C, and then dried in a constant temperature forced air drying oven at 60°C for 12 h to obtain a Prussian blue analog precursor catalytic material.

[0048] (3) The catalytic material obtained in step (2) is placed in a tubular furnace and subjected to heat treatment at 800° C. in three different atmospheres of nitrogen, hydrogen and argon using a thermal polymerization process. After heat treatment for 4 h, a Prussian blue analogue catalytic material is obtained.

[0049] The specific steps of the method for removing high-salt organic wastewater pollutants by activating PMS with Prussian blue analogue catalytic materials are as follows: Ultrapure water was taken as the background water sample, and the CQP pollutant solution was prepared with the water sample and mixed evenly, so that the initial concentration of the above pollutants was 30 mg / L. Different anions were added to simulate the reality of removing pollutants from water bodies in complex water samples. 30 mL of the above pollutant solution was taken, and Prussian blue analogue catalytic material was added to the water sample at a dosage of 20 mg, and then PMS 10 mg was added. The reaction was stirred for 1200 s at a stirring speed of 500 r / min, so that the CQP organic pollutants in the water were effectively degraded. The degradation situation is shown in the following figure. Figure 6 shown.

[0050] Example 4 A method for preparing a Prussian blue analogue catalytic material comprises the following steps: (1) Dissolve 0.012 mol potassium cobalt cyanide in 30 mL deionized water and stir at a stirring speed of 500 r / min to form solution A. Then, dissolve 0.008 mol copper nitrate and 0.6 g PVP in 30 mL deionized water and stir at a stirring speed of 500 r / min to form a mixed solution B.

[0051] (2) The mixed solution B obtained in step (1) is added dropwise to the solution A at a stirring speed of 500 r / min and a dropping speed of 1 mL / min, followed by co-precipitation treatment at 20-30°C, and then dried in a constant temperature forced air drying oven at 60°C for 12 h to obtain a Prussian blue analog precursor catalytic material.

[0052] (3) The catalytic material obtained in step (2) is placed in a tubular furnace and subjected to heat treatment at 800° C. in three different atmospheres of nitrogen, hydrogen and argon using a thermal polymerization process. After heat treatment for 5 h, a Prussian blue analogue catalytic material is obtained.

[0053] The specific steps of the method for removing high-salt organic wastewater pollutants by activating PMS with Prussian blue analogue catalytic materials are as follows: Take different water quality: tap water, Ningdong groundwater, Shahu surface water, Zhongwei Yellow River water, as background water samples, use different water samples to prepare CQP pollutant solution and mix evenly, so that the initial concentration of pollutants of different water quality is 30 mg / L, and the initial pH is not changed to simulate the reality of removing pollutants from water bodies in complex water samples. Take 30 mL of the above pollutant solution, add 20 mg of Lushi blue analog catalytic material to the water sample, and then add 10 mg of PMS, stir the reaction for 1200 s, and the stirring speed is 300 r / min, so that the organic pollutants in the water are effectively degraded. The degradation situation is as follows: Figure 7 shown.

[0054] The catalytic materials prepared in Examples 2 to 4 of the present invention have substantially the same morphology as the Prussian blue analogue catalytic material prepared in Example 1. Therefore, only the catalytic material prepared in Example 1 was subjected to electron microscope scanning. Figure 1 .

[0055] Comparative Example 1 A method for preparing a Prussian blue analogue catalytic material comprises the following steps: (1) Dissolve 0.003 mol potassium cobalt cyanide in 30 mL deionized water and stir at a stirring speed of 500 r / min to form solution A. Then, dissolve 0.002 mol copper nitrate and 0.6 g PVP in 30 mL deionized water and stir at a stirring speed of 500 r / min to form a mixed solution B.

[0056] (2) The mixed solution B obtained in step (1) is added dropwise to the solution A at a stirring speed of 300-500 r / min at a dropping speed of 1 mL / min, followed by co-precipitation treatment at 25°C, and then dried in a constant temperature forced air drying oven at 60°C for 12 h to obtain a Prussian blue analog precursor catalytic material.

[0057] (3) The catalytic material obtained in step (2) is placed in a tubular furnace and subjected to heat treatment at 800° C. in three different atmospheres of nitrogen, hydrogen and argon using a thermal polymerization process. After heat treatment for 3 h, a Prussian blue analogue catalytic material is obtained.

[0058] The method for activating PMS by using Prussian blue analogue catalytic materials to degrade and remove pollutants from high-salinity organic wastewater is as follows: The initial concentration of the prepared CQP pollutant solution was 30 mg / L. Without changing its initial pH, 20 mg of Prussian blue analogue catalytic material was added to 30 mL of the above pollutant solution. The mixture was stirred at a speed of 500 r / min and fully reacted for 1200 s. The degradation effect is shown in Figure 2 .

[0059] Comparative Example 2 The method of adding PMS alone to catalyze degradation and remove organic pollutants in water has the following specific steps: The initial concentration of the CQP pollutant solution was 30 mg / L, and the initial pH was not changed. 10 mg of PMS was added and stirred at a speed of 500 r / min for 1200 s. Figure 2 .

[0060] Comparative Example 3 The method of adding H2O2 alone to catalyze degradation and remove organic pollutants in water has the following specific steps: The initial concentration of the CQP pollutant solution was 30 mg / L, and the initial pH was not changed. 10 mL of H2O2 was added and stirred at a stirring speed of 500 r / min for 1200 s. Figure 2 .

[0061] Comparative Example 4 The method of adding PDS alone to catalyze degradation and remove organic pollutants in water has the following specific steps: The initial concentration of the CQP pollutant solution was 30 mg / L, and the initial pH was not changed. 10 mg of PDS was added and stirred at a stirring speed of 500 r / min for 1200 s. Figure 2 .

[0062] Performance Test: The degradation performance of the Prussian blue analogue catalytic materials prepared in Examples 2 to 4 of the present invention is basically the same as that of the catalytic material prepared in Example 1. The following test only takes the catalytic material prepared in Example 1 as an example.

[0063] The degradation curve of the organic pollutant chloroquine phosphate (CQP) over time in Example 1 is shown in Figure 2. The Prussian blue analogue catalytic material alone, that is, Comparative Example 1; PMS alone, that is, Comparative Example 2; H2O2 alone, that is, Comparative Example 3; PDS alone, that is, Comparative Example 4 and the combined process of Prussian blue analogue catalytic material / PMS catalytic material and Prussian blue analogue catalytic material / H2O2 catalytic material and Prussian blue analogue catalytic material / PDS catalytic material, that is, the degradation curve of the organic pollutant chloroquine phosphate (CQP) over time in Example 1 is shown in Figure 2. Figure 2 As shown in the figure, in the systems containing only Prussian blue analogue catalytic materials or different peroxides (PDS, PMS, H2O2), the removal efficiency of CQP was low and did not reach the expected goal of complete removal, indicating that the individual contributions of catalyst adsorption and oxidation of different peroxides were negligible. In general, peroxides have weak oxidation ability without external energy activation. Therefore, using high-performance Prussian blue analogues to activate peroxides seems to be an effective way to successfully degrade CQPs.

[0064] like Figure 2 As shown in the figure, the removal rate of CQP by the Prussian blue analogue catalytic material / PMS process is close to 100%, and the removal rate of CQP by the Prussian blue analogue catalytic material / H2O2 process is close to 95%, which proves that the Prussian blue analogue catalytic material can effectively activate PMS and H2O2 at the same time. In contrast, it is difficult for the Prussian blue analogue catalytic material to effectively activate PDS.

[0065] By comparing different processes, it can be concluded that the removal effect of Prussian blue analogue catalytic material / PMS catalytic material is greater than that of using Prussian blue analogue catalytic material process alone and PMS alone. After the Prussian blue analogue catalytic material activates PMS, it will produce a variety of highly active species, which increase the concentration of free radicals and non-free radicals in the solution, act together on CQP, promote its removal, and accelerate the reaction. Therefore, the Prussian blue analogue catalytic material / PMS catalytic material process has a synergistic strengthening effect, which can better remove a variety of organic pollutants. The removal rates of 30 mg / L rhodamine B, 30 mg / L methyl blue, 30 mg / L methyl orange, 30 mg / L tetracycline, 30 mg / L chloroquine phosphate, 20 mg / L norfloxacin, 20 mg / L phenol, 10 mg / L sulfamethoxazole and 10 mg / L sulfamethoxazole in the solution are as high as 100%, 100%, 100%, 100%, 100%, 96%, 92%, 93% and 86%.

[0066] from Figure 5 It can be seen that different initial solution pH values ​​have little effect on the degradation of CQP in the Prussian blue analogue catalytic material / PMS system. When the pH value is in the range of 3.0 to 11.0, the removal rate of CQP can be stabilized at about 95%. As the initial solution pH value drops to 2, the removal rate of CQP decreases significantly. This may be due to the fact that under strong acidic conditions, the abundant H + It is easy to react with the -OO- bond in PMS to form hydrogen bonds, thus affecting the •OH and SO4 in the system •- The above results show that the Prussian blue analogue catalytic material exhibits excellent adaptability in a wide pH range and can effectively activate PMS to achieve efficient degradation of CQP.

[0067] Figure 6 Common anions evaluated: HCO3 - 、CO3 2- , Cl - 、SO4 2- and H2PO4 - , on the Prussian blue analogue catalytic material / PMS system. When the addition amount was 5 mM, HCO3 -and CO3 2- The effect on CQP degradation was minimal, only decreasing from 100% to 95%, indicating that the Prussian blue analogue catalytic material / PMS process had little effect on HCO3 - and CO3 2- Has good applicability.

[0068] With SO4 2- and H2PO4 - The introduction of CQPs reduced the removal efficiency from 100% to 87%, which may be due to their inhibition of ROS generation. 2- It will increase the conductivity of the solution and affect the mass transfer process of the reaction and H2PO4 - Some carboxyl groups in the ions may have triggered complexation reactions, thereby reducing the diffusion and transport of pollutants and inhibiting PMS activation.

[0069] When adding Cl - The inhibitory effect on CQP was more obvious, decreasing from 100% to 15%. This is because Cl - The introduction of quenched SO4 •- free radicals and •OH free radicals, which promote the generation of Cl • , ClOH •- and Cl2 •- This affects the efficient degradation of CQP by highly active species in the system.

[0070] Figure 7 The effect of local actual water quality on the Prussian blue analogue catalytic material / PMS system was also evaluated, and it can be observed that the removal rate of the Prussian blue analogue catalytic material / PMS system for four different water bodies can be maintained at about 99%. In summary, the Prussian blue analogue catalytic material / PMS system exhibits ideal anti-interference ability and wide applicability for a variety of different coexisting substances contained in practical applications.

[0071] The Prussian blue analogue catalytic material prepared by the present invention not only exhibits excellent catalytic activity, but also has excellent recyclability and structural stability. In addition, the Prussian blue analogue catalytic material / PMS synergistic catalytic process can not only maintain high efficiency in a wide pH range, but also ensure effective treatment and purification of wastewater in harsh water quality environments such as high-concentration inorganic anions and actual water bodies. This shows that the Prussian blue analogue catalytic material has high potential value and applicability in wastewater remediation.

[0072] The above description is only a preferred embodiment of the present invention, and the above specific embodiment is not intended to limit the present invention. Various deformations and modifications may occur within the scope of the technical concept of the present invention, and any modification, modification or equivalent replacement made by a person of ordinary skill in the art based on the above description shall fall within the scope of protection of the present invention.

Claims

1. A method for preparing a Prussian blue analogue catalytic material, characterized in that: The following steps are involved: Soluble copper salt, transition metal potassium cyanide and polyvinyl pyrrolidone are placed in a solvent system, copper ions, transition metal ions and cyanide ions are subjected to coordination reaction to form a complex, and then the precursor is prepared by coprecipitation treatment; Under a protective atmosphere, the precursor is heat-treated to form a three-dimensional crystal network with oxygen defects and cyanide ions as bridges to connect transition metal ions and copper ions, thereby obtaining a Prussian blue analogue catalytic material; Wherein, the transition metal is cobalt or iron.

2. The method for preparing a Prussian blue analogue catalytic material according to claim 1, characterized in that: The molar ratio of the soluble copper salt to the transition metal potassium cyanide is 2-8:3-12.

3. The method for preparing a Prussian blue analogue catalytic material according to claim 1, characterized in that: The mass ratio of the soluble copper salt to the polyvinyl pyrrolidone is 5 to 11:

8.

4. The method for preparing a Prussian blue analogue catalytic material according to claim 1, characterized in that: The temperature of the heat treatment is 300°C to 900°C.

5. The method for preparing a Prussian blue analogue catalytic material according to claim 1, characterized in that: The temperature of the coprecipitation treatment is 20°C to 30°C.

6. The method for preparing a Prussian blue analogue catalytic material according to claim 1, characterized in that: The solvent of the solvent system is water.

7. The method for preparing a Prussian blue analogue catalytic material according to claim 1, characterized in that: The soluble copper salt includes any one of copper nitrate, copper sulfate and copper chloride.

8. A Prussian blue analogue catalytic material obtained by the preparation method of a Prussian blue analogue catalytic material according to any one of claims 1 to 7.

9. Use of the Prussian blue analogue catalytic material according to claim 8 in degrading high-salinity organic wastewater.

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