Polyphthalocyanine cobalt with defect structure and preparation method and application thereof

Abstract

The present invention discloses a polyphthalocyanine cobalt with a defective structure, a preparation method thereof, and an application thereof. The preparation method comprises the following steps: mixing the polyphthalocyanine cobalt with water and performing a hydrothermal reaction at 140°C to 185°C to obtain the polyphthalocyanine cobalt with a defective structure. The preparation method of the present invention does not introduce other chemical reagents and has the advantages of simple process, convenient operation, low cost, and environmental protection. The polyphthalocyanine cobalt with a defective structure obtained by the method has the advantages of rich pore structure, large specific surface area, more exposed active sites, fast electron transfer efficiency, and good recyclability. By combining a pathway with double non-free radicals (singlet oxygen and high-valent metal oxygen) as the leading factor and free radicals (sulfate radicals) as the auxiliary factor, it can effectively activate persulfate and achieve efficient degradation of organic pollutants.

Description

Technical Field

[0001] The invention belongs to the field of advanced oxidation water treatment, and particularly relates to a poly(cobalt phthalocyanine) with a defective structure, a preparation method thereof and an application thereof. Background Art

[0002] As an advanced oxidation process, persulfate oxidation not only offers advantages such as high efficiency, easy storage and transportation, low cost, and excellent stability, but also effectively overcomes the limitations of the traditional Fenton method, which reacts within a narrow pH range. That is, the Fenton method requires acidic conditions to achieve optimal results, while persulfate oxidation can react efficiently within a wider pH range, is more adaptable, and can be applied to different environmental conditions. These characteristics make persulfate an excellent choice for treating various organic pollutants, especially in wastewater treatment, soil remediation, and groundwater purification. In recent years, persulfate oxidation has received increasing attention and has become a research hotspot in the field of environmental catalysis.

[0003] Poly(cobalt phthalocyanine) is a polymerized cobalt phthalocyanine (CPPC) monomer. Composed of a cobalt metal center and four isoindole subunits, the CPPC monomer possesses 18 π electrons and is widely used in various catalytic processes. Theoretical studies have shown that the strong electronegativity of the nitrogen atom in the phthalocyanine ring can modulate the electron cloud density of adjacent atoms, forming metal-nitrogen active sites and promoting the adsorption of reactants. Furthermore, the unsaturated, low-coordination environment between the central cobalt metal ion and the four isoindole subunits imparts high catalytic activity to the metal center. However, the π-π stacking structure between CPPC molecules shields the active sites, limiting axial electron transfer and thus inhibiting the catalytic reaction. Therefore, further modification of CPPC is needed to enhance its catalytic performance. Currently, methods to improve the catalytic performance of CPPC typically involve the introduction of new functional groups or the loading of the CPPC onto other supports, which increases preparation costs and poses potential environmental risks. Therefore, finding a simple and green method to obtain CPPC with defective structures is of broad practical significance for the effective activation of persulfate and the efficient degradation of organic pollutants. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology and provide a polyphthalocyanine cobalt with a defective structure having rich pore structure, large specific surface area, more exposed active sites, fast electron transfer efficiency, and good recyclability, as well as a preparation method and application thereof.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions.

[0006] A method for preparing polycobalt phthalocyanine with a defective structure comprises the following steps: mixing polycobalt phthalocyanine with water, and performing a hydrothermal reaction at 140° C. to 185° C. to obtain polycobalt phthalocyanine with a defective structure.

[0007] The above preparation method is further improved in that the temperature of the hydrothermal reaction is 175°C to 185°C.

[0008] The above preparation method is further improved in that the time of the hydrothermal reaction is 4 hours to 8 hours, and the heating rate during the hydrothermal reaction is 2°C / min to 8°C / min.

[0009] The above preparation method is further improved, and the preparation method of polyphthalocyanine cobalt comprises the following steps: mixing pyromellitic dianhydride, urea, ammonium chloride, ammonium molybdate and cobalt chloride, and performing a polymerization reaction at 210° C. to 230° C. to obtain polyphthalocyanine cobalt.

[0010] The above preparation method is further improved, wherein the mass ratio of the pyromellitic dianhydride, urea, ammonium chloride, ammonium molybdate and cobalt chloride is 1-1.1:2-2.1:0.4-0.6:0.002-0.003:0.5-0.55, the heating rate during the polymerization reaction is 3°C / min-10°C / min, the polymerization reaction time is 2.5h-3.5h, and the polymerization reaction further includes the following treatments after the polymerization reaction: grinding, washing and drying the reaction product; the washing is carried out by washing with water and anhydrous ethanol in sequence, and the drying is vacuum drying at 60°C for 12h.

[0011] The above preparation method is further improved, wherein the ratio of the polyphthalocyanine cobalt to water is 200 mg to 300 mg: 30 mL to 50 mL, the mixing time is 15 min to 25 min, and the mixing is carried out under stirring conditions; after the hydrothermal reaction, the following treatment is also included: washing and drying the reaction product; the washing is carried out using water or anhydrous ethanol, and the drying is carried out in a vacuum at 60°C for 12 hours.

[0012] As a general technical concept, the present invention also provides a poly(cobalt phthalocyanine) with a defective structure obtained by the above-mentioned preparation method.

[0013] As a general technical concept, the present invention also provides a use of the above-mentioned poly(cobalt phthalocyanine) with defective structure in treating wastewater containing organic pollutants.

[0014] The above application is further improved, comprising the following steps: mixing polyphthalocyanine cobalt with a defective structure and organic pollutant wastewater, adding persulfate to carry out a degradation reaction to achieve degradation of organic pollutants in the water body; the ratio of the polyphthalocyanine cobalt with a defective structure to the organic pollutant wastewater is 0.03g to 0.2g:1L.

[0015] The above application is further improved, wherein the amount of persulfate added is 0.75 mmol to 1.25 mmol per liter of organic pollutant wastewater, the persulfate is potassium persulfate, the concentration of organic pollutants in the organic pollutant wastewater is ≤20 mg / L, the pH value of the organic pollutant wastewater is 3 to 11, the organic pollutants in the organic pollutant wastewater include at least one of antibiotics and dyes, the antibiotic is at least one of tetracycline hydrochloride, levofloxacin hydrochloride, ciprofloxacin and phenol, the dye is at least one of rose bengal B and methylene blue, the degradation reaction time is ≥5 min, the degradation reaction is carried out under stirring conditions, and the stirring speed is 300 rpm to 500 rpm.

[0016] Compared with the prior art, the advantages of the present invention are:

[0017] (1) In view of the defects of the current polyphthalocyanine cobalt modification process, such as the complex process, the easy introduction of other chemical substances and carriers leading to increased costs and environmental pollution, the present invention provides a preparation method of polyphthalocyanine cobalt with a defective structure constructed by a simple hydrothermal reaction, that is, mixing polyphthalocyanine cobalt with water, and conducting a hydrothermal reaction at 140°C to 185°C to obtain polyphthalocyanine cobalt with a defective structure. The polyphthalocyanine cobalt with a defective structure of the present invention forms defects on the polyphthalocyanine cobalt molecular plane at high temperature through a hydrothermal reaction. On the one hand, the defective structure can increase the porosity and specific surface area of ​​the catalyst material, thereby increasing the exposed active sites; on the other hand, the defective position can serve as a channel for electron transfer, promoting electron transfer; at the same time, graphite carbon, graphite nitrogen, carbonyl and other structures are formed in the hydrothermal modification process, which can serve as active sites for persulfate adsorption and activation, thereby enhancing the removal effect of pollutants. The defective polyphthalocyanine cobalt of the present invention has advantages such as a rich pore structure, a large specific surface area, more exposed active sites, high electron transfer efficiency, and good recyclability. It can effectively activate percarbonate and achieve efficient degradation of organic pollutants through a pathway that combines a dual non-free radical (singlet oxygen and high-valent metal oxygen) as the main agent and a free radical (sulfate radical) as the auxiliary agent. The preparation method of the present invention has the advantages of simple process, convenient operation, low cost, and environmental protection. It provides new ideas for the modification and design of organic polymers and has certain practical application significance for the remediation and treatment of difficult-to-degrade organic pollutants in wastewater.

[0018] (2) The preparation method of the present invention can obtain polyphthalocyanine cobalt with a defective structure having higher catalytic activity by optimizing the temperature of the hydrothermal reaction to 175°C to 185°C. When the hydrothermal reaction temperature is too low, the defective structure and graphitic nitrogen cannot be formed or the amount is small; when the hydrothermal reaction temperature is too high, the hydrothermal reaction will be unstable and there is a risk of explosion.

[0019] (3) The present invention also provides an application of polyphthalocyanine cobalt with a defective structure in treating organic pollutant wastewater. The polyphthalocyanine cobalt with a defective structure is mixed with organic pollutant wastewater, and persulfate is added for catalytic reaction, thereby effectively degrading organic pollutants in the water body. There are multiple degradation mechanisms in the degradation system of polyphthalocyanine cobalt with a defective structure / persulfate of the present invention, namely, the double non-radical pathway of singlet oxygen and high-valent metal oxygen is the main one, supplemented by sulfate radical, thereby showing a high organic pollutant removal rate. Specifically, the life span of non-radicals is longer than that of free radicals, which improves the efficiency of active oxygen, and they have strong anti-interference ability to the environment, can maintain high efficiency in degrading organic pollutants in a wide pH range, and have strong resistance to the adverse effects of various ions in the water body. It has the advantages of simple operation, good degradation effect, low cost, etc., and is suitable for practical application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 These are SEM images of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with a defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2.

[0021] Figure 2 XRD patterns of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2.

[0022] Figure 3 Isothermal adsorption-desorption curves of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2.

[0023] Figure 4 The pore size distribution diagrams are of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2.

[0024] Figure 5These are Raman spectra of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with a defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2.

[0025] Figure 6 The Raman spectra of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2 are in the range of 1200-1700 cm -1 Peak separation diagram at wavelength.

[0026] Figure 7 These are the full XPS spectra of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2.

[0027] Figure 8 These are the N1s peak diagrams of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2.

[0028] Figure 9 These are infrared spectra of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with a defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2.

[0029] Figure 10 This is a diagram showing the effects of poly(cobalt phthalocyanine) (CoPPc), poly(cobalt phthalocyanine) with defective structure (D-CoPPc-180), modified poly(cobalt phthalocyanine) (D-CoPPc-100), and modified poly(cobalt phthalocyanine) (D-CoPPc-140) in Example 2 of the present invention on the degradation of tetracycline hydrochloride.

[0030] Figure 11 This is a graph showing the degradation of tetracycline hydrochloride by cobalt polyphthalocyanine (D-CoPPc-180) with a defective structure under different pH conditions in Example 3 of the present invention.

[0031] Figure 12This is a diagram showing the degradation effect of cobalt polyphthalocyanine (D-CoPPc-180) with a defective structure on different pollutants in Example 4 of the present invention. DETAILED DESCRIPTION

[0032] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but the scope of protection of the present invention is not limited thereby. The materials and instruments used in the following examples are all commercially available.

[0033] Example 1:

[0034] A method for preparing poly(cobalt phthalocyanine) having a defective structure of the present invention comprises the following steps:

[0035] (1) Weigh 1.05 g of pyromellitic dianhydride, 2.05 g of urea, 0.5 g of ammonium chloride, 0.00225 g of ammonium molybdate, and 0.528 g of cobalt chloride in a mortar, grind and mix them evenly by hand, transfer them to a crucible after grinding, and wrap them with tin foil; transfer the crucible to a muffle furnace, heat it to 220 °C at a heating rate of 3 °C / min, hold for 3 h, and take it out after the muffle furnace cools to room temperature; grind the reaction product into powder in a mortar, and filter and wash it three times with ultrapure water and anhydrous ethanol respectively, and dry it in a vacuum at 60 °C for 12 h to obtain cobalt polyphthalocyanine, denoted as CoPPc.

[0036] (2) Weigh 200 mg of the cobalt polyphthalocyanine powder obtained in step (1) using an analytical balance and place it in a Teflon liner. Add 30 mL of deionized water and stir vigorously for 20 min. Seal the liner in a hydrothermal reactor and perform a hydrothermal reaction at 180° C. for 6 hours. After the reactor is cooled to room temperature, take out the product, wash it three times with deionized water, and then dry it in a vacuum drying oven at 60° C. for 12 hours to obtain a cobalt polyphthalocyanine with a defective structure, which is recorded as D-CoPPc-180.

[0037] Comparative Example 1:

[0038] A modified cobalt polyphthalocyanine (CPPC) is prepared by a method substantially identical to the method for preparing the cobalt polyphthalocyanine (D-CoPPc-180) having a defective structure in Example 1, with the only difference being that in step (2), the hydrothermal reaction temperature is 100° C. The obtained modified cobalt polyphthalocyanine is designated as D-CoPPc-100.

[0039] Comparative Example 2:

[0040] A modified cobalt polyphthalocyanine (CPPC), the preparation method of which is substantially the same as the preparation method of the cobalt polyphthalocyanine (D-CoPPc-180) with a defective structure in Example 1, except that in step (2), the temperature of the hydrothermal reaction is 140° C.; the modified cobalt polyphthalocyanine obtained is designated as D-CoPPc-140.

[0041] Figure 1 These are SEM images of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with a defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2. Figure 1 In the figure, (a), (c), (e), and (g) are SEM images of CoPPc, D-CoPPc-100, D-CoPPc-140, and D-CoPPc-180 at 50,000 times magnification, and (b), (d), (f), and (h) are SEM images of CoPPc, D-CoPPc-100, D-CoPPc-140, and D-CoPPc-180 at 5,000 times magnification. Figure 1 It can be seen that CoPPc, D-CoPPc-100, D-CoPPc-140, and D-CoPPc-180 all exhibit irregular block structures, while the original CoPPc has a smooth surface. However, as the hydrothermal reaction temperature increases, the surface of the cobalt polyphthalocyanine catalyst becomes increasingly wrinkled and roughened, increasing the specific surface area of ​​the catalyst, exposing more active sites and facilitating the adsorption and activation of pollutants and persulfate.

[0042] Figure 2 The XRD patterns of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2 are shown. Figure 2It can be seen that due to the different interlayer arrangements, the crystal domains inside CoPPc can be deconvoluted into two π-π stacking crystal forms, namely the uniformly arranged α type and the staggered β type. The characteristic diffraction peaks of the CoPPc sample at 2θ = 17.3°, 18.4°, 18.8°, 27.1°, 29.4° and 30.4° are attributed to the (200), (001), and (101) planes of β-CoPPc, the interlayer stacking of the aromatic system, and the (001) and (101) planes of α-CoPPc, respectively. The XRD spectra of the modified samples are very different from those of the original samples. D-CoPPc-X (X = 100, 140, 180) does not inherit the sharp and narrow characteristic diffraction peak of CoPPc, and only retains the diffraction peak of about 27.14°, which indicates that the hydrothermal reaction at high temperature can destroy the crystal structure of CoPPc and transform it into an amorphous property; at the same time, with the increase of the hydrothermal reaction temperature, a new characteristic diffraction peak appears at around 22°, which may be related to the (002) plane reflection of the graphite structure of the carbon material. This shows that a higher hydrothermal reaction temperature can form a graphite phase in the sample, and the graphite phase can serve as a medium for electron transfer, thereby increasing the rate of electron transfer.

[0043] Figure 3 Isothermal adsorption-desorption curves of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2. Figure 4 The pore size distribution diagrams are shown for the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2. Figure 3 It can be seen that the surface areas of the catalysts are 3.8253m 2 g -1 (CoPPc), 5.0163m 2 g -1 (D-CoPPc-100), 5.1843m 2 g -1 (D-CoPPc-140), 5.3441m 2 g -1 (D-CoPPc-180), which proves that the surface area of ​​cobalt polyphthalocyanine with defective structure increases with the increase of hydrothermal reaction temperature, which is consistent with the results of SEM images. Figure 4As can be seen, the pore size of each catalyst is distributed around 20 nm, which is mesoporous. This shows that the defective polyphthalocyanine cobalt of the present invention has the advantages of large specific surface area and rich pore structure, which is conducive to the exposure of active sites, thereby promoting the adsorption of organic pollutants and improving mass transfer efficiency, ultimately effectively promoting the degradation of organic pollutants.

[0044] Figure 5 These are Raman spectra of cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, cobalt polyphthalocyanine with a defect structure (D-CoPPc-180), modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2. Figure 6 The Raman spectra of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2 are in the range of 1200-1700 cm -1 The peak diagram at different wavelengths. Figure 5 and Figure 6 It can be seen that the Raman spectra of different samples are highly similar, with the peaks at 684, 1454, and 1540 cm -1 A 1g 、B 2g and B 1g The bands represent the C–N–C stretching of isoindole, while the bands at 748, 1125, and 1331 cm -1 B1g and two A 1g The bands represent the N–M stretching of isoindole. In addition, at 1350 cm -1 and 1590cm -1 Two distinguishable peaks, D and G, appeared at 1200–1700 cm -1 The peaks of the bands were analyzed and the D and G bands were separated. The ratio of the D peak to the G peak intensity can reflect the degree of catalyst defects. The larger the ratio, the higher the degree of defects. D / I G The ratios are 0.280, 0.275, 0.449, and 0.651, respectively, which indicates that the hydrothermal reaction at 100 °C cannot effectively create defects on the polyphthalocyanine cobalt plane, and defects can only be formed under high-temperature hydrothermal conditions.

[0045] Figure 7These are the full XPS spectra of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2. Figure 8 The N1s peak diagrams of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2 are shown. Figure 7 and Figure 8 The full-spectrum scan spectra of each catalyst show distinct signals for C, N, O, and Co, the primary elements that make up cobalt polyphthalocyanine (CPC). Notably, the high-resolution XPS N 1s spectra of each sample exhibit peaks at 399.03 eV, 400.10 eV, and 404.58 eV, respectively, attributable to pyridinic N, Co-N bonds, and oxidized N species. Compared to CoPPc and D-CoPPc-100, the N 1s spectra of D-CoPPc-140 and D-CoPPc-180 exhibit a new peak at approximately 402.00 eV, attributable to graphitic nitrogen. This indicates that graphitic nitrogen forms within the structure of cobalt polyphthalocyanine (CPC) under high-temperature hydrothermal conditions, and that the hydrothermal temperature is proportional to the graphitic nitrogen content. The defective polyphthalocyanine cobalt (D-CoPPc-180) of the present invention can effectively activate persulfate. This is because: on the one hand, graphitic nitrogen can serve as the main active site for PMS activation. Due to the high electronegativity of graphitic nitrogen, it can destroy the balance of the nearby sp2 hybridized carbon (graphitic carbon) network and promote the transfer of electrons from nearby carbon atoms to nitrogen atoms; on the other hand, PMS molecules have a strong affinity with graphitic nitrogen with high electron density and are easily enriched near graphitic nitrogen. Then, PMS can quickly self-decompose into singlet oxygen.

[0046] Figure 9 The infrared spectra of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with defect structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2 are shown. Figure 9 It can be seen that the FT-IR spectra of different materials are roughly the same, with the C–H groups at 642–744 cm -1 There are oscillation and torsional vibrations at 1521 and 1612 cm -1 There are CC absorption peaks at 1317 and 1138 cm -1 Stretching vibration occurs at 1571 cm -1Stretching vibration occurs at 1060-1421 cm -1 The difference is that after hydrothermal modification, the O–H and N–H stretching vibrations of the hydroxyl and amino groups appear at 3120 cm -1 This indicates that the hydrothermal reaction has a positive effect on the formation of new functional groups on the surface of polyphthalocyanine cobalt. In addition, the characteristic peaks corresponding to the carboxylic acid bond and the amide bond appear at 1697 cm -1 and 1680cm -1 These characteristic peaks only appear in the FT-IR spectra of D-CoPPc-140 and D-CoPPc-180. Amide bonds are formed by the dehydration condensation of amino and carboxyl groups. When the amino and carboxyl groups originate from different polyphthalocyanine molecular planes, the formation of an amide bond can reduce the interlayer spacing between the two planes and enhance intermolecular interactions. Furthermore, amide bonds can form hydrogen bonds within and between molecules, which may also actively contribute to intermolecular interactions and electron transfer.

[0047] Example 2:

[0048] An application of the present invention of polyphthalocyanine cobalt with a defective structure in treating organic pollutant wastewater, specifically using the polyphthalocyanine cobalt with a defective structure to degrade tetracycline hydrochloride (TC) in water, comprises the following steps:

[0049] 5 mg of each of the cobalt polyphthalocyanine (CoPPc) prepared in Example 1 of the present invention, the cobalt polyphthalocyanine with a defective structure (D-CoPPc-180), the modified cobalt polyphthalocyanine (D-CoPPc-100) prepared in Comparative Example 1, and the modified cobalt polyphthalocyanine (D-CoPPc-140) prepared in Comparative Example 2 were added to 100 mL of a tetracycline hydrochloride (TC) solution having a concentration of 10 mg / L and a pH of 4.86; then, 1 mL of a potassium persulfate solution (the concentration of the solution was 100 mM) was added to bring the concentration of potassium persulfate (PMS) in the reaction system to 1 mM. The catalytic reaction was carried out at room temperature and 450 rpm for 60 min to complete the degradation of tetracycline hydrochloride.

[0050] Figure 10 The figure shows the effect of polyphthalocyanine cobalt (CoPPc), polyphthalocyanine cobalt with defect structure (D-CoPPc-180), modified polyphthalocyanine cobalt (D-CoPPc-100), and modified polyphthalocyanine cobalt (D-CoPPc-140) in Example 2 of the present invention on the degradation of tetracycline hydrochloride. Figure 10It can be seen that as the hydrothermal reaction temperature increases, the catalyst's activation performance for PMS gradually improves, and the TC removal rate increases from 68% to 95.9%. Even at a lower hydrothermal reaction temperature (100°C), the catalyst's activation effect on PMS and TC removal rate can be improved. The defective cobalt phthalocyanine (D-CoPPc-180) of the present invention removed 95.9% of TC within 60 minutes. This is because: 1) the surface area of ​​the modified catalyst increases, exposing more active sites; 2) the formation of the defective structure provides a channel for axial electron transfer, promoting electron transfer to PMS and facilitating PMS activation; 3) the graphitic nitrogen, graphitic carbon, and a large number of carbonyl groups formed during the modification process can serve as new active sites, enhancing the adsorption of pollutants on the catalyst surface and activating PMS to form singlet oxygen and sulfate radicals, thereby exhibiting the highest tetracycline hydrochloride (TC) removal rate.

[0051] Example 3:

[0052] An application of the present invention of polyphthalocyanine cobalt with a defective structure in treating organic pollutant wastewater, specifically using the polyphthalocyanine cobalt with a defective structure to degrade tetracycline hydrochloride (TC) in water environments with different pH values, comprises the following steps:

[0053] Take 5 cups of 100 mL of tetracycline hydrochloride (TC) solution with a concentration of 10 mg / L and a pH of 4.86, and use 0.1 M sulfuric acid and 0.1 M sodium hydroxide solution to adjust the pH of the tetracycline solution to 3, 5, 7, 9, and 11, respectively; then, add 5 mg of the defective polyphthalocyanine cobalt (D-CoPPc-180) prepared in Example 1; then, add 1 mL of potassium persulfate solution (the concentration of the solution is 100 mM) to make the concentration of potassium persulfate (PMS) in the reaction system 1 mM, and carry out the catalytic reaction at room temperature and 450 rpm for 60 min to complete the degradation of tetracycline hydrochloride.

[0054] Figure 11 This is a graph showing the degradation of tetracycline hydrochloride by cobalt phthalocyanine (D-CoPPc-180) with defective structure in Example 3 of the present invention under different pH conditions. Figure 11 As shown in the figure, the degradation of TC is significantly inhibited only when the initial pH value is 3, and the degradation of TC is almost unaffected under other pH conditions. In a strong acid environment, the degradation of TC by D-CoPPc-180 is inhibited. The main reasons are: 1) H + and (Introduced when adjusting pH) can react with OH and Reaction; 2) H + Can stabilize PMS and hinder its activation; 3)H +This can destroy the active sites and surface functional groups of the catalyst, inhibit the formation of CoOH+ complexes, and make it difficult for PMS to activate. Overall, the D-CoPPc-180 / PMS system has good adaptability over a wide pH range.

[0055] Example 4:

[0056] The invention discloses an application of a polyphthalocyanine cobalt with a defective structure in treating organic pollutant wastewater, specifically utilizing the polyphthalocyanine cobalt with a defective structure to degrade Rose Bengal B (RhB), methylene blue (MB), levofloxacin hydrochloride (LFX), ciprofloxacin (CIP), and phenol (Phenol) in water, comprising the following steps:

[0057] Five portions of cobalt polyphthalocyanine (D-CoPPc-180) with defective structures prepared in Example 1 of the present invention, 5 mg each, were added to beakers containing 100 mL of each pollutant-containing solution at a concentration of 10 mg / L, respectively. Then, 1 mL of potassium persulfate solution (100 mM concentration) was added to bring the potassium persulfate (PMS) concentration in the reaction system to 1 mM. The catalytic reaction was carried out at room temperature and 450 rpm for 60 min to complete the degradation of different pollutants.

[0058] Figure 12 The figure shows the degradation effect of cobalt polyphthalocyanine (D-CoPPc-180) with defective structure on different pollutants in Example 4 of the present invention. Figure 12 It can be seen that the D-CoPPc-180 / PMS system has a high removal efficiency for organic dyes (RhB and MB) and phenols (Phenol), especially RhB and MB, which are completely removed within 5 minutes and 40 minutes respectively. The degradation efficiency of fluoroquinolones (LXF and CIP) is moderate, and the removal rate remains above 80% within 60 minutes. The difference in degradation efficiency of different pollutants shows that 1 O2 and Co(IV)=O have selective catalytic properties.

[0059] The above description is only a preferred embodiment of the present invention and does not constitute any formal limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the spirit and technical solution of the present invention, use the methods and technical contents disclosed above to make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention, still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for preparing poly(cobalt phthalocyanine) having a defective structure, characterized in that: The following steps are involved: Mixing polyphthalocyanine cobalt and water, and performing a hydrothermal reaction at 140° C. to 185° C. to obtain polyphthalocyanine cobalt with a defect structure; the hydrothermal reaction time is 4 hours to 8 hours; the ratio of the polyphthalocyanine cobalt to water is 200 mg to 300 mg: 30 mL to 50 mL, the mixing time is 15 minutes to 25 minutes, and the mixing is performed under stirring; after the hydrothermal reaction, the following treatments are also included: washing and drying the reaction product; The cleaning is performed by using water or anhydrous ethanol, and the drying is performed by vacuum drying at 60° C. for 12 hours; The preparation method of the polyphthalocyanine cobalt comprises the following steps: mixing pyromellitic dianhydride, urea, ammonium chloride, ammonium molybdate and cobalt chloride, and performing a polymerization reaction at 210°C to 230°C to obtain the polyphthalocyanine cobalt; the mass ratio of the pyromellitic dianhydride, urea, ammonium chloride, ammonium molybdate and cobalt chloride is 1-1.1:2-2.1:0.4-0.6:0.002-0.003:0.5-0.55; the heating rate during the polymerization reaction is 3°C / min to 10°C / min; the polymerization reaction time is 2.5h to 3.5h; and after the polymerization reaction, the following treatments are further included: grinding, washing and drying the reaction product; the washing is performed by sequentially washing with water and anhydrous ethanol, and the drying is performed by vacuum drying at 60°C for 12h.

2. The method for preparing polyphthalocyanine cobalt with defect structure according to claim 1, characterized in that: The temperature of the hydrothermal reaction is 175°C to 185°C.

3. A poly(cobalt phthalocyanine) with a defective structure obtained by the preparation method according to claim 1 or 2.

4. Use of the poly(cobalt phthalocyanine) with defective structure as claimed in claim 3 in treating wastewater containing organic pollutants.

5. The use according to claim 4, characterized in that The method comprises the following steps: mixing polyphthalocyanine cobalt with a defective structure and organic pollutant wastewater, adding persulfate to carry out degradation reaction, and realizing degradation of organic pollutants in water; the ratio of the polyphthalocyanine cobalt with a defective structure to the organic pollutant wastewater is 0.03g-0.2g:1L.

6. The use according to claim 5, characterized in that The amount of persulfate added is 0.75 mmol to 1.25 mmol per liter of organic pollutant wastewater, the persulfate is potassium persulfate, the concentration of organic pollutants in the organic pollutant wastewater is ≤20 mg / L, the pH value of the organic pollutant wastewater is 3 to 11, the organic pollutants in the organic pollutant wastewater include at least one of antibiotics and dyes, the antibiotic is at least one of tetracycline hydrochloride, levofloxacin hydrochloride, ciprofloxacin and phenol, the dye is at least one of rose bengal B and methylene blue, the degradation reaction time is ≥5 min, the degradation reaction is carried out under stirring conditions, and the stirring speed is 300 rpm to 500 rpm.

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